JP4677706B2 - Secondary battery - Google Patents

Description

【００３６】
で示される部分構造を分子内に有するＮ−オキサイド化合物を含有し、
前記負極は、炭素を主成分とする第一の層と、第一の層と異なる材料であってリチウム成分を吸蔵および放出することのできるリチウムイオン導電性材料からなる第二の層と、金属リチウム、リチウム合金、窒化リチウム、Ｌｉ _3-x Ｍ _x Ｎ（Ｍ＝Ｃｏ、Ｎｉ、Ｃｕ）から選ばれる一種または二種以上からなる第三の層とを含み、第一の層と第三の層との間に第二の層が配置された多層構造を有することを特徴とする二次電池が提供される。
【００３７】
【発明の実施の形態】
本発明に係る二次電池においては、以下の構成を採用することができる。
【００３８】
〔正極の構成〕
本発明の二次電池の正極は、必須の正極活物質として、下記一般式（１）で示される部分構造を分子内に有するＮ−オキサイド化合物を含有する。
【００３９】
【化７】

【００４０】
一般式（１）で示される部分構造を分子内に有するＮ−オキサイド化合物の好適な例として、下記一般式（２）で示される部分構造を分子内に有するＮ−オキサイド化合物（以後「キノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物」と呼ぶ）が挙げられる。
【００４１】
【化８】

【００４２】
一般式（２）において、Ｒ₁〜Ｒ₄はそれぞれ独立に、水素原子、ハロゲン原子、ヒドロキシル基、ニトロ基、ニトロソ基、シアノ基、カルボキシル基、置換もしくは非置換のアルキル基、置換もしくは非置換のアルケニル基、置換もしくは非置換のシクロアルキル基、置換もしくは非置換の芳香族炭化水素基、置換もしくは非置換の芳香族複素環基、置換もしくは非置換のアラルキル基、置換もしくは非置換のアミノ基、置換もしくは非置換のアルコキシ基、置換もしくは非置換のアリールオキシ基、置換もしくは非置換のアルコキシカルボニル基、置換もしくは非置換のアリールオキシカルボニル基、置換もしくは非置換のアシル基、又は置換もしくは非置換のアシルオキシ基を示す。また、これらの置換基は、その一個以上の原子が硫黄原子、ケイ素原子、リン原子、又はホウ素原子で置換されていてもよく、また置換基同士で環構造を形成していてもよい。
【００４３】
また一般式（１）で示される部分構造を分子内に有するＮ−オキサイド化合物の好適な例として、下記一般式（３）又は（４）で示される部分構造を分子内に有するＮ−オキサイド化合物が挙げられる。
【００４４】
【化９】

【００４５】
一般式（３）において、Ｒ₁〜Ｒ₈はそれぞれ独立に、水素原子、ハロゲン原子、ヒドロキシル基、ニトロ基、ニトロソ基、シアノ基、カルボキシル基、置換もしくは非置換のアルキル基、置換もしくは非置換のアルケニル基、置換もしくは非置換のシクロアルキル基、置換もしくは非置換の芳香族炭化水素基、置換もしくは非置換の芳香族複素環基、置換もしくは非置換のアラルキル基、置換もしくは非置換のアミノ基、置換もしくは非置換のアルコキシ基、置換もしくは非置換のアリールオキシ基、置換もしくは非置換のアルコキシカルボニル基、置換もしくは非置換のアリールオキシカルボニル基、置換もしくは非置換のアシル基、又は置換もしくは非置換のアシルオキシ基を示す。また、これらの置換基は、その一個以上の原子が硫黄原子、ケイ素原子、リン原子、又はホウ素原子で置換されていてもよく、また置換基同士で環構造を形成していてもよい。
【００４６】
【化１０】

【００４７】
一般式（４）において、Ｒ₁〜Ｒ₈はそれぞれ独立に、水素原子、ハロゲン原子、ヒドロキシル基、ニトロ基、ニトロソ基、シアノ基、カルボキシル基、置換もしくは非置換のアルキル基、置換もしくは非置換のアルケニル基、置換もしくは非置換のシクロアルキル基、置換もしくは非置換の芳香族炭化水素基、置換もしくは非置換の芳香族複素環基、置換もしくは非置換のアラルキル基、置換もしくは非置換のアミノ基、置換もしくは非置換のアルコキシ基、置換もしくは非置換のアリールオキシ基、置換もしくは非置換のアルコキシカルボニル基、置換もしくは非置換のアリールオキシカルボニル基、置換もしくは非置換のアシル基、又は置換もしくは非置換のアシルオキシ基を示す。また、これらの置換基は、その一個以上の原子が硫黄原子、ケイ素原子、リン原子、又はホウ素原子で置換されていてもよく、また置換基同士で環構造を形成していてもよい。
【００４８】
上記一般式（１）〜（４）で示される部分構造を分子内に有するＮ−オキサイド化合物は低分子化合物でもオリゴマー又はポリマー化合物でもよい。高分子化合物の場合、その形状は鎖状、分岐状、網目状であってもよい。
【００４９】
また、前記一般式（１）で示される部分構造を分子内に有するその他のＮ−オキサイド化合物として、下記一般式（５）で示される構造を有する化合物が挙げられ、例えばピラジン化合物（ｎ＋ｍ＋ｎ’＋ｍ’＝０を満たすもの）やポリアセン型ジアジン−Ｎ，Ｎ’−ジオキサイド化合物（ｎ＋ｍ＋ｎ’＋ｍ’≧１を満たすもの）、これらのピラジン化合物またはポリアセン型ジアジン−Ｎ，Ｎ’−ジオキサイド化合物の縮合環に２つの結合手をもつ二価基を構造単位として有するオリゴマー又はポリマー化合物（以後これらの化合物を「直鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドオリゴマー又はポリマー化合物」と呼ぶ）、または上記ピラジン化合物またはポリアセン型ジアジン−Ｎ，Ｎ’−ジオキサイド化合物の縮合環に一つの結合手を持つ一価基を有する構造単位を有するオリゴマー又はポリマー化合物（以後これらの化合物を「側鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドオリゴマー又はポリマー化合物」と呼ぶ）も挙げられる。
【００５０】
【化１１】

【００５１】
一般式（５）において、ｎ、ｍ、ｎ’及びｍ’はそれぞれ独立に０以上の整数を示す。また、ジアジン環とベンゼン環との縮合の順序は交互であってもランダムであってもよい。また、Ｒ₁、Ｒ₂、Ｒ₃、Ｒ₄、Ｒ^a、Ｒ^b、Ｒ^c、及びＲ^dのうち、一つ又は二つは前記結合手であってもよく、その場合の残りの置換基、及び結合手を持たない場合は全ての置換基は、それぞれ独立に、水素原子、ハロゲン原子、ヒドロキシル基、ニトロ基、ニトロソ基、シアノ基、カルボキシル基、置換もしくは非置換のアルキル基、置換もしくは非置換のアルケニル基、置換もしくは非置換のシクロアルキル基、置換もしくは非置換の芳香族炭化水素基、置換もしくは非置換の芳香族複素環基、置換もしくは非置換のアラルキル基、置換もしくは非置換のアミノ基、置換もしくは非置換のアルコキシ基、置換もしくは非置換のアリールオキシ基、置換もしくは非置換のアルコキシカルボニル基、置換もしくは非置換のアリールオキシカルボニル基、置換もしくは非置換のアシル基、又は置換もしくは非置換のアシルオキシ基を示す。ただし、ｎが２以上の場合、Ｒ^a及びＲ^bはそれぞれ同一であっても異なっていてもよく、ｎ’が２以上の場合、Ｒ^c及びＲ^dはそれぞれ同一であっても異なっていてもよい。また、これらの置換基は、その一個以上の原子が硫黄原子、ケイ素原子、リン原子、又はホウ素原子で置換されていてもよく、また置換基同士で環構造を形成していてもよい。
【００５２】
上記一般式（２）〜（５）において、置換基Ｒ₁、Ｒ₂、Ｒ₃、Ｒ₄、Ｒ₅、Ｒ₆、Ｒ₇、Ｒ₈、Ｒ^a、Ｒ^b、Ｒ^c及びＲ^dのハロゲン原子としては、例えば、フッ素、塩素、臭素、ヨウ素等が挙げられ、一種単独または二種以上を組み合わせて有することができる。
【００５３】
また置換または非置換のアルキル基としては、例えば、メチル基、エチル基、プロピル基、イソプロピル基、ｎ−ブチル基、ｓ−ブチル基、イソブチル基、ｔ−ブチル基、ｎ−ペンチル基、ｎ−ヘキシル基、ｎ−ヘプチル基、ｎ−オクチル基、ヒドロキシメチル基、１−ヒドロキシエチル基、２−ヒドロキシエチル基、２−ヒドロキシイソブチル基、１，２−ジヒドロキシエチル基、１，３−ジヒドロキシイソプロピル基、２，３−ジヒドロキシ−ｔ−ブチル基、１，２，３−トリヒドロキシプロピル基、クロロメチル基、１−クロロエチル基、２−クロロエチル基、２−クロロイソブチル基、１，２−ジクロロエチル基、１，３−ジクロロイソプロピル基、２，３−ジクロロ−ｔ−ブチル基、１，２，３−トリクロロプロピル基、ブロモメチル基、１−ブロモエチル基、２−ブロモエチル基、２−ブロモイソブチル基、１，２−ジブロモエチル基、１，３−ジブロモイソプロピル基、２，３−ジブロモ−ｔ−ブチル基、１，２，３−トリブロモプロピル基、ヨードメチル基、１−ヨードエチル基、２−ヨードエチル基、２−ヨードイソブチル基、１，２−ジヨードエチル基、１，３−ジヨードイソプロピル基、２，３−ジヨード−ｔ−ブチル基、１，２，３−トリヨードプロピル基、アミノメチル基、１−アミノエチル基、２−アミノエチル基、２−アミノイソブチル基、１，２−ジアミノエチル基、１，３−ジアミノイソプロピル基、２，３−ジアミノ−ｔ−ブチル基、１，２，３−トリアミノプロピル基、シアノメチル基、１−シアノエチル基、２−シアノエチル基、２−シアノイソブチル基、１，２−ジシアノエチル基、１，３−ジシアノイソプロピル基、２，３−ジシアノ−ｔ−ブチル基、１，２，３−トリシアノプロピル基、ニトロメチル基、１−ニトロエチル基、２−ニトロエチル基、２−ニトロイソブチル基、１，２−ジニトロエチル基、１，３−ジニトロイソプロピル基、２，３−ジニトロ−ｔ−ブチル基、１，２，３−トリニトロプロピル基等が挙げられ、一種単独または二種以上を組み合わせて有することができる。
【００５４】
また置換または非置換のアルケニル基としては、例えば、ビニル基、アリル基、１−ブテニル基、２−ブテニル基、３−ブテニル基、１，３−ブタンジエニル基、１−メチルビニル基、スチリル基、２，２−ジフェニルビニル基、１，２−ジフェニルビニル基、１−メチルアリル基、１，１−ジメチルアリル基、２−メチルアリル基、１−フェニルアリル基、２−フェニルアリル基、３−フェニルアリル基、３，３−ジフェニルアリル基、１，２−ジメチルアリル基、１−フェニル−１−ブテニル基、３−フェニル−１−ブテニル基等が挙げられ、一種単独または二種以上を組み合わせて有することができる。
【００５５】
また置換または非置換のシクロアルキル基としては、例えば、シクロプロピル基、シクロブチル基、シクロペンチル基、シクロヘキシル基、４−メチルシクロヘキシル基等が挙げられ、一種単独または二種以上を組み合わせて有することができる。
【００５６】
また置換または非置換の芳香族炭化水素基としては、例えば、フェニル基、１−ナフチル基、２−ナフチル基、９−フルオレニル基、１−アントリル基、２−アントリル基、９−アントリル基、１−フェナントリル基、２−フェナントリル基、３−フェナントリル基、４−フェナントリル基、９−フェナントリル基、１−ナフタセニル基、２−ナフタセニル基、９−ナフタセニル基、１−ピレニル基、２−ピレニル基、４−ピレニル基、２−ビフェニルイル基、３−ビフェニルイル基、４−ビフェニルイル基、ｐ−ターフェニル−４−イル基、ｐ−ターフェニル−３−イル基、ｐ−ターフェニル−２−イル基、ｍ−ターフェニル−４−イル基、ｍ−ターフェニル−３−イル基、ｍ−ターフェニル−２−イル基、ｏ−トリル基、ｍ−トリル基、ｐ−トリル基、ｐ−ｔ−ブチルフェニル基、ｐ−（２−フェニルプロピル）フェニル基、３−メチル−２−ナフチル基、４−メチル−１−ナフチル基、４−メチル−１−アントリル基、４’−メチルビフェニルイル基、４”−ｔ−ブチル−ｐ−ターフェニル−４−イル基、及びこれらの誘導体等が挙げられ、これらの一種単独または二種以上を組み合わせて有することができる。
【００５７】
また置換または非置換の芳香族複素環基としては、１−ピロリル基、２−ピロリル基、３−ピロリル基、ピラジニル基、２−ピリジニル基、３−ピリジニル基、４−ピリジニル基、１−インドリル基、２−インドリル基、３−インドリル基、４−インドリル基、５−インドリル基、６−インドリル基、７−インドリル基、１−イソインドリル基、２−イソインドリル基、３−イソインドリル基、４−イソインドリル基、５−イソインドリル基、６−イソインドリル基、７−イソインドリル基、２−フリル基、３−フリル基、２−ベンゾフラニル基、３−ベンゾフラニル基、４−ベンゾフラニル基、５−ベンゾフラニル基、６−ベンゾフラニル基、７−ベンゾフラニル基、１−イソベンゾフラニル基、３−イソベンゾフラニル基、４−イソベンゾフラニル基、５−イソベンゾフラニル基、６−イソベンゾフラニル基、７−イソベンゾフラニル基、２−キノリル基、３−キノリル基、４−キノリル基、５−キノリル基、６−キノリル基、７−キノリル基、８−キノリル基、１−イソキノリル基、３−イソキノリル基、４−イソキノリル基、５−イソキノリル基、６−イソキノリル基、７−イソキノリル基、８−イソキノリル基、２−キノキサリニル基、５−キノキサリニル基、６−キノキサリニル基、１−カルバゾリル基、２−カルバゾリル基、３−カルバゾリル基、４−カルバゾリル基、９−カルバゾリル基、１−フェナンスリジニル基、２−フェナンスリジニル基、３−フェナンスリジニル基、４−フェナンスリジニル基、６−フェナンスリジニル基、７−フェナンスリジニル基、８−フェナンスリジニル基、９−フェナンスリジニル基、１０−フェナンスリジニル基、１−アクリジニル基、２−アクリジニル基、３−アクリジニル基、４−アクリジニル基、９−アクリジニル基、１，７−フェナンスロリン−２−イル基、１，７−フェナンスロリン−３−イル基、１，７−フェナンスロリン−４−イル基、１，７−フェナンスロリン−５−イル基、１，７−フェナンスロリン−６−イル基、１，７−フェナンスロリン−８−イル基、１，７−フェナンスロリン−９−イル基、１，７−フェナンスロリン−１０−イル基、１，８−フェナンスロリン−２−イル基、１，８−フェナンスロリン−３−イル基、１，８−フェナンスロリン−４−イル基、１，８−フェナンスロリン−５−イル基、１，８−フェナンスロリン−６−イル基、１，８−フェナンスロリン−７−イル基、１，８−フェナンスロリン−９−イル基、１，８−フェナンスロリン−１０−イル基、１，９−フェナンスロリン−２−イル基、１，９−フェナンスロリン−３−イル基、１，９−フェナンスロリン−４−イル基、１，９−フェナンスロリン−５−イル基、１，９−フェナンスロリン−６−イル基、１，９−フェナンスロリン−７−イル基、１，９−フェナンスロリン−８−イル基、１，９−フェナンスロリン−１０−イル基、１，１０−フェナンスロリン−２−イル基、１，１０−フェナンスロリン−３−イル基、１，１０−フェナンスロリン−４−イル基、１，１０−フェナンスロリン−５−イル基、２，９−フェナンスロリン−１−イル基、２，９−フェナンスロリン−３−イル基、２，９−フェナンスロリン−４−イル基、２，９−フェナンスロリン−５−イル基、２，９−フェナンスロリン−６−イル基、２，９−フェナンスロリン−７−イル基、２，９−フェナンスロリン−８−イル基、２，９−フェナンスロリン−１０−イル基、２，８−フェナンスロリン−１−イル基、２，８−フェナンスロリン−３−イル基、２，８−フェナンスロリン−４−イル基、２，８−フェナンスロリン−５−イル基、２，８−フェナンスロリン−６−イル基、２，８−フェナンスロリン−７−イル基、２，８−フェナンスロリン−９−イル基、２，８−フェナンスロリン−１０−イル基、２，７−フェナンスロリン−１−イル基、２，７−フェナンスロリン−３−イル基、２，７−フェナンスロリン−４−イル基、２，７−フェナンスロリン−５−イル基、２，７−フェナンスロリン−６−イル基、２，７−フェナンスロリン−８−イル基、２，７−フェナンスロリン−９−イル基、２，７−フェナンスロリン−１０−イル基、１−フェナジニル基、２−フェナジニル基、１−フェノチアジニル基、２−フェノチアジニル基、３−フェノチアジニル基、４−フェノチアジニル基、１０−フェノチアジニル基、１−フェノキサジニル基、２−フェノキサジニル基、３−フェノキサジニル基、４−フェノキサジニル基、１０−フェノキサジニル基、２−オキサゾリル基、４−オキサゾリル基、５−オキサゾリル基、２−オキサジアゾリル基、５−オキサジアゾリル基、３−フラザニル基、２−チエニル基、３−チエニル基、２−メチルピロール−１−イル基、２−メチルピロール−３−イル基、２−メチルピロール−４−イル基、２−メチルピロール−５−イル基、３−メチルピロール−１−イル基、３−メチルピロール−２−イル基、３−メチルピロール−４−イル基、３−メチルピロール−５−イル基、２−ｔ−ブチルピロール−４−イル基、３−（２−フェニルプロピル）ピロール−１−イル基、２−メチル−１−インドリル基、４−メチル−１−インドリル基、２−メチル−３−インドリル基、４−メチル−３−インドリル基、２−ｔ−ブチル−１−インドリル基、４−ｔ−ブチル−１−インドリル基、２−ｔ−ブチル−３−インドリル基、４−ｔ−ブチル−３−インドリル基、及びこれらの誘導体等が挙げられ、これらの一種単独または二種以上を組み合わせて有することができる。
【００５８】
また置換または非置換のアラルキル基としては、例えば、ベンジル基、１−フェニルエチル基、２−フェニルエチル基、１−フェニルイソプロピル基、２−フェニルイソプロピル基、フェニル−ｔ−ブチル基、α−ナフチルメチル基、１−α−ナフチルエチル基、２−α−ナフチルエチル基、１−α−ナフチルイソプロピル基、２−α−ナフチルイソプロピル基、β−ナフチルメチル基、１−β−ナフチルエチル基、２−β−ナフチルエチル基、１−β−ナフチルイソプロピル基、２−β−ナフチルイソプロピル基、１−ピロリルメチル基、２−（１−ピロリル）エチル基、ｐ−メチルベンジル基、ｍ−メチルベンジル基、ｏ−メチルベンジル基、ｐ−クロロベンジル基、ｍ−クロロベンジル基、ｏ−クロロベンジル基、ｐ−ブロモベンジル基、ｍ−ブロモベンジル基、ｏ−ブロモベンジル基、ｐ−ヨードベンジル基、ｍ−ヨードベンジル基、ｏ−ヨードベンジル基、ｐ−ヒドロキシベンジル基、ｍ−ヒドロキシベンジル基、ｏ−ヒドロキシベンジル基、ｐ−アミノベンジル基、ｍ−アミノベンジル基、ｏ−アミノベンジル基、ｐ−ニトロベンジル基、ｍ−ニトロベンジル基、ｏ−ニトロベンジル基、ｐ−シアノベンジル基、ｍ−シアノベンジル基、ｏ−シアノベンジル基、１−ヒドロキシ−２−フェニルイソプロピル基、１−クロロ−２−フェニルイソプロピル基等が挙げられ、これらの一種単独または二種以上を組み合わせて有することができる。
【００５９】
また置換または非置換のアミノ基は、−ＮＸ¹Ｘ²で表される基であり、置換基Ｘ¹およびＸ²は、それぞれ独立に、例えば、水素原子、上述の置換または非置換のアルキル基、置換または非置換のアルケニル基、置換または非置換のシクロアルキル基、置換または非置換の芳香族炭化水素基、置換または非置換の芳香族複素環基、置換または非置換のアラルキル基等が挙げられ、これらの一種単独または二種以上を組み合わせて有することができる。
【００６０】
また置換または非置換のアルコキシ基および置換または非置換のアルコキシカルボニル基は、それぞれ−ＯＸ³および−ＣＯＯＸ⁴で表される基であり、置換基Ｘ³およびＸ⁴としてはそれぞれ、例えば、上述の置換または非置換のアルキル基、置換または非置換のシクロアルキル基、置換または非置換のアラルキル基等が挙げられ、これらの一種単独または二種以上を組み合わせて有することができる。
【００６１】
また置換または非置換のアリールオキシ基および置換または非置換のアリールオキシカルボニル基は、それぞれ−ＯＸ⁵および−ＣＯＯＸ⁶で表される基であり、置換基Ｘ⁵およびＸ⁶としてはそれぞれ、例えば、上述の置換または非置換の芳香族炭化水素基、置換または非置換の芳香族複素環基等が挙げられ、これらの一種単独または二種以上を組み合わせて有することができる。
【００６２】
また置換または非置換のアシル基および置換または非置換のアシルオキシ基は、それぞれ−Ｃ(＝Ｏ)Ｘ⁷および−ＯＣ(＝Ｏ)Ｘ⁸で表される基であり、置換基Ｘ⁷およびＸ⁸としてはそれぞれ、例えば、水素原子、上述の置換または非置換のアルキル基、置換または非置換アルケニル基、置換または非置換シクロアルキル基、置換または非置換の芳香族炭化水素基、置換または非置換の芳香族複素環基、置換または非置換アラルキル基等が挙げられ、これらの一種単独または二種以上を組み合わせて有することができる。
【００６３】
また環を形成する２価基の例としては、テトラメチレン基、ペンタメチレン基、ヘキサメチレン基、ジフェニルメタン−２，２'−ジイル基、ジフェニルエタン−３，３'−ジイル基、ジフェニルプロパン−４，４'−ジイル基、１，３−ブタジエン−１，４−ジイル基、及びこれらの誘導体等が挙げられる。
【００６４】
また上述の置換基は、その一個以上の原子が硫黄原子、ケイ素原子、リン原子、またはホウ素原子で置換されていてもよい。硫黄原子で置換された基としては、例えば、上述のヒドロキシル基、カルボキシル基、アルコキシ基、アルコキシカルボニル基、アリールオキシ基、アリールオキシカルボニル基、アシル基、アシルオキシ基等の酸素含有基の酸素原子が硫黄原子で置き換えられた置換基を挙げることができる。その置換基の例としては、メルカプト基、ジチオカルボキシル基、ヒドロキシ（チオカルボニル）基、メルカプトカルボニル基、メチルチオ基、メトキシチオカルボニル基、メチルチオカルボニル基、メチルジチオカルボキシル基、フェニルチオ基、フェノキシチオカルボニル基、フェニルチオカルボニル基、フェニルジチオカルボニル基、メチルチオカルボニル基、フェニルチオカルボニル基、等が挙げられる。ケイ素原子で置換された基としては、例えば、上述のアルキル基、アルケニル基、シクロアルキル基、アラルキル基の炭素原子がケイ素原子で置き換えられた置換基を挙げることができる。その置換基の例としては、シリル基、メチルシリル基、シリルメチル基、エチルシリル基、（メチルシリル）メチル基、ジメチルシリル基、トリメチルシリル基、ｔ−ブチルジメチルシリル基、トリイソプロピルシリル基、等が挙げられる。リン原子で置換された基としては、例えば、上述のアミノ基の窒素原子がリン原子で置き換えられた置換基が挙げられる。その置換基の例としては、ホスフィノ基、トリメチルホスフィノ基、トリフェニルホスフィノ基、等が挙げられる。ホウ素原子で置換された基としては、例えば、上述のアミノ基の窒素原子がリン原子で置き換えられた置換基が挙げられる。その置換基の例としては、ジメチルボリル基、ジフェニルボリル基、等が挙げられる。
【００６５】
以下にＮ−オキサイド化合物の具体例を示すが、これらに限定されるものではない。
【００６６】
キノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物の具体例としては、以下の化学式（６）〜（１８）に示す化合物が挙げられる。これらの式においてｎ、ｍ、ｏがある場合、それぞれ２以上の整数を表す。
【００６７】
【化１２】

【００６８】
【化１３】

【００６９】
【化１４】

【００７０】
【化１５】

【００７１】
【化１６】

【００７２】
【化１７】

【００７３】
【化１８】

【００７４】
【化１９】

【００７５】
【化２０】

【００７６】
【化２１】

【００７７】
【化２２】

【００７８】
【化２３】

【００７９】
【化２４】

【００８０】
本発明におけるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物は、一般式（１９）で表されるｐ−フェニレンジアミン構造を部分構造として有する化合物を過酸化水素、ｔ−ブチルヒドロペルオキシド、過酸化ベンゾイル等の有機過酸化物、過酢酸、過安息香酸、ｍ−クロロ過安息香酸等の有機過酸、ペルオキソ硫酸などの酸化剤で酸化することにより得ることができる。また、一般式（１９）で表されるｐ−フェニレンジアミン構造を部分構造として有する化合物を酸化銀、酸化鉛、酢酸鉛、塩化鉄（III）、ヘキサシアノ鉄（III）酸カリウム等の酸化剤により酸化し、一般式（２０）で表されるｐ−キノンジイミン構造を部分構造として有する化合物とし、さらにこれを過酸化水素、ｔ−ブチルヒドロペルオキシド、過酸化ベンゾイル等の有機過酸化物、過酢酸、過安息香酸、ｍ−クロロ過安息香酸等の有機過酸、ペルオキソ硫酸などの酸化剤で酸化することにより得ることができる。また、一般式（２０）で表されるｐ−キノンジイミン構造を部分構造として有する化合物を過酸化水素、ｔ−ブチルヒドロペルオキシド、過酸化ベンゾイル等の有機過酸化物、過酢酸、過安息香酸、ｍ−クロロ過安息香酸等の有機過酸、ペルオキソ硫酸などの酸化剤で酸化することにより得ることができる。
【００８１】
【化２５】

【００８２】
（一般式（１９）においてＲ¹〜Ｒ⁴はそれぞれ独立に、水素原子、置換もしくは非置換のアルキル基、置換もしくは非置換のアルケニル基、置換もしくは非置換の芳香族炭化水素基、置換もしくは非置換の芳香族複素環基、置換もしくは非置換のアラルキル基、ハロゲン原子、ヒドロキシル基、ニトロ基、ニトロソ基、シアノ基、カルボキシル基、置換もしくは非置換のアミノ基、置換もしくは非置換のアルコキシ基、置換もしくは非置換のアリールオキシ基、置換もしくは非置換のアルコキシカルボニル基、置換もしくは非置換のアリールオキシカルボニル基、置換もしくは非置換のアシル基、置換もしくは非置換のアシルオキシ基を表す）
【００８３】
【化２６】

【００８４】
（一般式（２０）においてＲ¹〜Ｒ⁴はそれぞれ独立に、水素原子、置換もしくは非置換のアルキル基、置換もしくは非置換のアルケニル基、置換もしくは非置換の芳香族炭化水素基、置換もしくは非置換の芳香族複素環基、置換もしくは非置換のアラルキル基、ハロゲン原子、ヒドロキシル基、ニトロ基、ニトロソ基、シアノ基、カルボキシル基、置換もしくは非置換のアミノ基、置換もしくは非置換のアルコキシ基、置換もしくは非置換のアリールオキシ基、置換もしくは非置換のアルコキシカルボニル基、置換もしくは非置換のアリールオキシカルボニル基、置換もしくは非置換のアシル基、置換もしくは非置換のアシルオキシ基を表す）
一般式（１９）及び（２０）のＲ¹〜Ｒ⁴としてはそれぞれ、一般式（２）〜（５）の置換基として例示したものを挙げることができる。
【００８５】
Ｃ．Ｊ．ペーダーセン(C.J.Pedersen)、ジャーナル・オブ・ザ・アメリカン・ケミカル・ソサエティー（Jornal of the American Chemical Society）、２２９５頁〜２２９９頁（１９５７年）には、Ｎ，Ｎ’−ジフェニル−ｐ−キノンジイミン−Ｎ，Ｎ’−ジオキサイド（化学式（６））、Ｎ，Ｎ’−ジシクロヘキシル−ｐ−キノンジイミン−Ｎ，Ｎ’−ジオキサイド（化学式（８））などの合成法が記載されている。これによれば、Ｎ，Ｎ’−ジフェニル−ｐ−キノンジイミン−Ｎ，Ｎ’−ジオキサイドは、Ｎ，Ｎ’−ジフェニル−ｐ−フェニレンジアミンを原料とし、これを過酸化ベンゾイルで酸化し、Ｎ，Ｎ’−ジフェニル−ｐ−キノンジイミンとし、さらに、これを過安息香酸により酸化することにより得ることができる。また、Ｎ，Ｎ’−ジシクロヘキシル−ｐ−キノンジイミン−Ｎ，Ｎ’−ジオキサイドは、Ｎ，Ｎ’−ジシクロヘキシル−ｐ−フェニレンジアミンを原料とし、これを過安息香酸により酸化することにより得ることができる。
【００８６】
ピラジン化合物、及びポリアセン型ジアジン−Ｎ，Ｎ’−ジオキサイド化合物の具体例としては、以下の化学式（２１）〜（２９）に示す化合物が挙げられる。
【００８７】
【化２７】

【００８８】
【化２８】

【００８９】
【化２９】

【００９０】
【化３０】

【００９１】
【化３１】

【００９２】
【化３２】

【００９３】
【化３３】

【００９４】
【化３４】

【００９５】
【化３５】

【００９６】
直鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドオリゴマー又はポリマー化合物の具体例としては、以下の化学式（３０）〜（３７）に示す化合物が挙げられる。これらの式においてｎは２以上の整数を表す。
【００９７】
【化３６】

【００９８】
【化３７】

【００９９】
【化３８】

【０１００】
【化３９】

【０１０１】
【化４０】

【０１０２】
【化４１】

【０１０３】
【化４２】

【０１０４】
【化４３】

【０１０５】
側鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドオリゴマー又はポリマー化合物の具体例としては、以下の化学式（３８）〜（４４）に示す化合物が挙げられる。これらの式においてｎ、ｍはそれぞれ２以上の整数を表す。
【０１０６】
【化４４】

【０１０７】
【化４５】

【０１０８】
【化４６】

【０１０９】
【化４７】

【０１１０】
【化４８】

【０１１１】
【化４９】

【０１１２】
【化５０】

【０１１３】
本発明におけるジアジンＮ，Ｎ’−ジオキサイド化合物は、対応するジアジン化合物を過酸化物あるいは過酸を用いて酸化するなどの既知の合成法により製造することができる。
【０１１４】
ピラジン化合物及びポリアセン型ジアジン−Ｎ，Ｎ’−ジオキサイド化合物の合成法としては、例えば過酸化尿素を用いる方法が、シンレット、１９９０年９月、５３３〜５３５頁（Synlett, P533-535, September 1990）に記載されている。また、化学式（２３）で表される化合物ならば、フェナジンのジクロロメタン溶液に、メタクロロ過安息香酸のジクロロメタン溶液を添加し室温で攪拌し、その後、炭酸ナトリウムの飽和水溶液を加えて中和し、常法に従って精製することによって得ることができる。
【０１１５】
直鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドオリゴマー又はポリマー化合物は、例えば次のようにして製造することができる。直鎖型ジアジンオリゴマー又はポリマー化合物を過酸化物と反応させ、縮合環内の窒素原子をＮ−オキシド化することによって得ることができる。他の方法として、ポリアセン型ジアジンＮ，Ｎ’−ジオキサイド化合物の縮合環が有する置換基のうちの二つがハロゲンであるジハライド化合物を、有機溶媒中において、ゼロ価ニッケル化合物を加えて脱ハロゲン化して得ることができる。
【０１１６】
側鎖型ジアジンＮ，Ｎ'−ジオキサイド構造を側鎖に有するオリゴマー又はポリマー化合物は、対応するジアジン誘導体により置換されたオレフィンを例えばラジカル重合させることによりオリゴマー化又はポリマー化し、これを過酸化物あるいは過酸を用いて酸化するなどの既知の合成法により製造することができる。例えば、ポリ（２−ビニルピラジン−Ｎ，Ｎ’−ジオキサイド）の合成法については、イラニアン・ジャーナル・オブ・サイエンス・アンド・テクノロジ、１９８７年、第１１巻、第１号、第２７〜３４頁（Iranian Journal of Science ＆ Technology, P.27-34, Vol.11, No.1, 1987）に記載されている。
【０１１７】
本発明の二次電池において、正極活物質は固体状態であっても、また、電解質へ溶解または分散した状態であってもよい。ただし固体状態で用いる場合は、電解液への溶解による容量低下を防ぐため、電解液に対して不溶性または低溶解性のものが好ましい。
【０１１８】
本発明におけるＮ−オキサイド化合物のオリゴマー又はポリマーは、Ｎ−オキサイド構造を有するモノマーだけから重合したホモポリマーであっても、また他のモノマーとの共重合体であってもよい。
【０１１９】
本発明の二次電池の正極において、活物質であるＮ−オキサイド化合物は、単独で用いることもできるが、二種類以上を組み合わせて用いてもよい。また、金属酸化物粒子、ジスルフィド化合物、及び導電性高分子等の他の正極活物質と組み合わせて用いてもよい。金属酸化物としては、ＬｉＭｎＯ₂、Ｌｉ_xＭｎ₂Ｏ₄(０＜ｘ＜２)等のマンガン酸リチウムもしくはスピネル構造を有するマンガン酸リチウム、ＭｎＯ₂、ＬｉＣｏＯ₂、ＬｉＮｉＯ₂、Ｌｉ_xＶ₂Ｏ₅(０＜ｘ＜２)等が挙げられ、ジスルフィド化合物としては、ジチオグリコール、２，５−ジメルカプト−１，３，４−チアジアゾール、Ｓ−トリアジン−２，４，６−トリチオール等が挙げられ、導電性高分子としては、ポリアセチレン、ポリフェニレン、ポリアニリン、ポリピロール等が挙げられる。
【０１２０】
本発明におけるＮ−オキサイド化合物は、正極内で正極活物質として機能し、電極反応の放電反応および充電反応において、反応出発物、生成物または中間生成物として電極中に含有される。
【０１２１】
また、本発明の二次電池の製造時において、Ｎ−オキサイド化合物をそのまま用いてもよいし、電極反応によってＮ−オキサイド構造に変換され得る化合物を用いて製造してもよい。このような電極反応によって前記Ｎ−オキサイド化合物に変化する化合物の例としては、前記Ｎ−オキサイド化合物を還元したアニオン体のリチウム塩、あるいは、前記Ｎ−オキサイド化合物を酸化したカチオン体と電解質アニオンとからなる塩などが挙げられる。
【０１２２】
また本発明では、電極反応をより円滑に行うために酸化還元反応を促進させる触媒を電極材料に混合してもよい。このような触媒としては、ポリアニリン、ポリピロール、ポリチオフェン、ポリアセチレン、ポリアセン等の導電性高分子、ピリジン誘導体、ピロリドン誘導体、ベンズイミダゾール誘導体、ベンゾチアゾール誘導体、アクリジン誘導体等の塩基性化合物、ならびに金属イオン錯体等が挙げられる。
【０１２３】
〔負極の構成〕
本発明における負極は、炭素を主成分とする第一の層と、リチウム成分を吸蔵および放出することのできる材料からなる第二の層と、リチウム及びリチウム含有化合物の少なくとも一方を含む第三の層とを含み、第一の層と第三の層との間に第二の層が配置された多層構造を有する。第一、第二、第三の層はそれぞれ単層でも複数層でもよい。第一、第二、第三の層の位置関係については、第一の層と第三の層とが直に接してはならず、これらの間に第二の層が介在する。第一、第二、第三の層が複数存在する場合は第一の層と第三の層とが直に接しなければいかなる積層構造もとることができる。すなわち、以下に示すいずれの形態であってもよい。
（ａ）第一の層が電極最表面に配置された構成。
（ｂ）第二の層が電極最表面に配置された構成。
（ｃ）第三の層が電極最表面に配置された構成。
【０１２４】
また、第二の層と第三の層からなる多層膜を第一の層の上部および下部に第一の層を第二の層で挟むように配置した構成や、第一の層と第二の層からなる多層膜を第三の層の上部および下部に第三の層を第二の層で挟むように配置した構成を採用することもできる。このように、第一の層が第二の層に挟まれた配置、あるいは第三の層が第二の層に挟まれた配置とすることにより、高い充放電効率および良好なサイクル特性を維持しつつ、電池容量を一層向上させることができる。
【０１２５】
本発明において、第二の層はリチウム成分を吸蔵および放出することのできる材料からなるものとすることが望ましい。リチウム成分を吸蔵する形態としては、合金等を形成する形態のほか、当該材料と合金を形成することなく構造体中にリチウムを取り込む形態も含む。
【０１２６】
本発明の負極において、第二の層はアモルファス構造とすることが好ましい。アモルファス構造への電気化学的なＬｉのドープ・脱ドープは、結晶構造よりも卑な電位で起こるため、高い動作電圧および高い充放電効率を維持しつつ電池容量を増加させることができる。ここで、本発明におけるアモルファスとは、ＣｕＫα線を用いたＸ線回折法の２θ値で１５〜４０度に頂点を有するブロードな散乱帯を有するものをいう。
【０１２７】
アモルファス構造は、結晶体と比較して、構造的に等方であるため外部からの応力に対する強度に優れる上、化学的に安定である。このため電解液と反応を起こしにくく、充放電のサイクルを繰り返した際の安定性に優れ、容量劣化が発生しにくい。
【０１２８】
また第二の層は、蒸着法、ＣＶＤ法またはスパッタリング法により形成した層とすることが好ましい。これらの成膜法を用いた場合、アモルファス状のリチウムイオン導電性膜が負極上に均一に得られる。この膜により正極と負極間の電解分布を均一にすることができる。このため電界の局所的集中が起こらず、サイクルを経ても集電体から活物質が剥離する等の破損が発生せず安定した電池特性が得られる。
【０１２９】
本発明における第二の層を構成するリチウムイオン導電性材料は、リチウム成分を透過できる材料であれば特に制限はないが、Ｓｉ、Ｇｅ、Ａｇ、Ｓｎ、Ｉｎ及びＰｂからなる群から選択される一または二以上の元素を含むものが挙げられ、Ｓｉ、Ｇｅ、Ａｇ、Ｓｎ、Ｉｎ、Ｐｂ、これらの酸化物あるいは複合酸化物、及びこれらの硫化物あるいは複合硫化物からなる群から選択される一または二以上の材料が好ましい。また、Ｂ₂Ｏ₃、Ｐ₂Ｏ₅、Ａｌ₂Ｏ₃、Ｗ_hＯ_3h-1（ｈ＝１、２、３、４）、Ｍｏ_iＯ_3i-1（ｉ＝１、２、３、４）、ＴｉＯ、ＴｉＯ₂からなる群から選択される一または二以上の材料も用いることができる。これらはリチウムもしくはリチウムイオンを吸蔵及び放出することのできる材料である。このような材料を選択し、かつアモルファス構造を具備することにより、高い動作電圧および高い充放電効率を維持しつつ電池容量を増加させることができる。特に、第二の層を、Ｓｉ、Ｇｅ、Ｓｎ、Ｐｂ及びこれらの酸化物からなる群から選択される一または二以上の材料からなるものとすれば、動作電圧、充放電効率および電池容量をより顕著に改善できる上、製造も容易となる点から、これらの材料が好ましい。このうち、特にＳｉ、Ｓｎ及びこれらの酸化物は、リチウムを吸蔵した際の構造変化が小さく、充放電を繰り返しても劣化しにくく、良好なサイクル特性が得られる点で好ましい。
【０１３０】
本発明において、第三の層を構成する物質はＬｉ又はＬｉ含有化合物であれば特に制限はないが、好ましくは金属リチウム、リチウム合金、窒化リチウムやＬｉ_3-xＭ_xＮ（Ｍ＝Ｃｏ、Ｎｉ、Ｃｕ）等のリチウム窒化物、これらの一または二以上を含む混合物である。このような材料は電気化学的に多くのリチウムを放出することができるため、電池のエネルギー密度を向上させることができる。
【０１３１】
また本発明において、第三の層を構成する物質はアモルファス構造とすることが好ましい。アモルファス構造は、結晶と比較して、構造的に等方であるため化学的に安定で電解液と副反応を起こしにくい。このため、第三の層に含まれるＬｉが電池エネルギー密度の向上に効果的に利用される。
【０１３２】
また本発明において、第三の層を構成する物質は、蒸着法、ＣＶＤ法またはスパッタリング法により形成した層とすることが好ましい。これらの成膜法を用いた場合、負極全体に均一なアモルファス状の層を作製することができる。また溶媒を用いる必要がないため、副反応が起こりにくくより純度の高い層を作製することができ、第三の層に含まれるＬｉが電池エネルギー密度の向上に効果的に利用される。
【０１３３】
図１、図２、図４、図５に、本発明の二次電池における負極の構造例（断面構造）を示す。
【０１３４】
集電体１は、充放電の際、電流を電池の外部に取り出したり外部から電池内に電流を取り込んだりするための電極部材である。この集電体１は導電性の金属箔であればよく、たとえば、Ａｌ、Ｃｕ、ステンレス、Ａｕ、Ｗ、Ｍｏ等を用いることができる。
【０１３５】
炭素負極２は、前記の第一の層に相当し、充放電の際、Ｌｉを吸蔵あるいは放出する負極部材である。この炭素負極２はＬｉを吸蔵可能な炭素であり、例えば、天然黒鉛、石油コークス、石炭コークス、ピッチコークス、カーボンブラック、樹脂焼成炭素、有機高分子焼成体、熱分解気相成長炭素繊維、メソカーボンマイクロビーズ、メソフェーズピッチ系炭素繊維、ポリアクリロニトリル系炭素繊維、低温焼成炭素、フラーレン、カーボンナノチューブ等の炭素材料、及びこれらの混合物を例示できる。
【０１３６】
第２負極層３は、前記の第二の層に相当し、リチウムイオン導電性を持つ負極部材である。このような材料としてＢ₂Ｏ₃、Ｐ₂Ｏ₅、Ａｌ₂Ｏ₃、Ｗ_hＯ_3h-1（ｈ＝１、２、３、４）、Ｍｏ_iＯ_3i-1（ｉ＝１、２、３、４）、ＴｉＯ、ＴｉＯ₂、並びにＳｉ、Ｇｅ、Ａｇ、Ｓｎ、Ｉｎ、Ｐｂ、これらの酸化物あるいは複合酸化物および硫化物あるいは複合硫化物が挙げられ、これらを単独または一種以上を組み合わせて用いることができる。また、リチウムイオン導電性を高めるために、この材料にハロゲン化リチウム、リチウムカルコゲナイド等を添加してもよい。またこの材料はアモルファスであることが好ましい。アモルファス材料を用いることにより、リチウムのドープ・脱ドープが起こる電位を結晶に比べて卑にすることができ、この結果、電池の動作電圧を高くすることができる。また第２負極層３は、ＣＶＤ法、蒸着法、またはスパッタ法により形成することが好ましい。これらの方法で作製すれば、アモルファス層を均一な膜質および膜厚で形成することができる。
【０１３７】
第３負極層４は、前記の第三の層に相当し、リチウム又はリチウム含有化合物からなる負極部材である。このような材料として、金属リチウム、リチウム合金、リチウム窒化物（窒化リチウム（Ｌｉ₃Ｎ）やＬｉ_3-xＭ_xＮ（Ｍ＝Ｃｏ、Ｎｉ、Ｃｕ）等）及びこれらの混合物が挙げられ、これらを単独または一種以上を組み合わせて用いることができる。またこの材料はアモルファスであることが好ましい。アモルファス材料を用いることにより、電解液との副反応を抑制し、材料中に含まれるリチウムを効率よく不可逆容量の補填に利用することができる。この結果、電池の初回充放電効率が向上し、エネルギー密度を高くすることができる。第３負極層４は、ＣＶＤ法、蒸着法、またはスパッタ法により形成することが好ましい。これらの方法で作製すれば、アモルファス層を均一な膜質および膜厚で形成することができる。
【０１３８】
負極の積層構造は、図１に示すように集電体１上に、炭素負極層２（第１負極層）、第２負極層３、及び第３負極層４の順で積層された構造、図２に示すように集電体１の両面にそれぞれ炭素負極層２、第２負極層３、及び第３負極層４の順で積層された構造、図４に示すように図１に示す積層構造の第３負極層４上にさらに第２負極層３及び炭素負極層２が積層された構造、図５に示すように集電体１上に、第３負極層４、第２負極層３、炭素負極層２、第２負極層３、及び第３負極層４の順で積層された構造を採用することもできる。
【０１３９】
〔導電補助材およびイオン伝導補助材〕
本発明では、電極を形成する際に、インピーダンスを低下させる目的で、導電補助材やイオン伝導補助材を混合させてもよい。導電補助材としては、グラファイト、カーボンブラック、アセチレンブラック、気相成長炭素繊維等の炭素質微粒子、銅、銀、金、白金等の金属微粒子、ポリアニリン、ポリピロール、ポリチオフェン、ポリアセチレン、ポリアセン等の導電性高分子が挙げられる。また、イオン伝導補助材としては、ゲル電解質、固体電解質が挙げられる。
【０１４０】
〔結着剤〕
本発明では、電極の各構成材料間の結びつきを強めるために、電極材料に結着剤を混合してもよい。このような結着剤としては、ポリフッ化ビニリデン、ビニリデンフルオライド−ヘキサフルオロプロピレン共重合体、ビニリデンフルオライド−テトラフルオロエチレン共重合体、スチレン−ブタジエン共重合ゴム、ポリテトラフルオロエチレン、ポリプロピレン、ポリエチレン、ポリイミド等の樹脂バインダーが挙げられる。
【０１４１】
〔集電体およびセパレータ〕
本発明おける集電体としては、ニッケル、アルミニウム、銅、金、銀、アルミニウム合金、ステンレス等の金属箔や金属平板、メッシュ状電極、炭素電極等を用いることができる。また、このような集電体に触媒効果を持たせたり、活物質と集電体とを化学結合させたりしてもよい。
【０１４２】
また、負極集電体と正極集電体との電気的接触を防ぐ目的で、両者の間にプラスティック樹脂等からなる絶縁パッキンを配置した構成としてもよい。
【０１４３】
また、本発明のリチウム二次電池において用いることのできるセパレータとしては、ポリプロピレン、ポリエチレン等のポリオレフィン、フッ素樹脂等の多孔性フィルムを用いることができる。
【０１４４】
〔電解液及び電解質〕
本発明における電解液としては、プロピレンカーボネート（ＰＣ）、エチレンカーボネート（ＥＣ）、ブチレンカーボネート（ＢＣ）、ビニレンカーボネート（ＶＣ）等の環状カーボネート類、ジメチルカーボネート（ＤＭＣ）、ジエチルカーボネート（ＤＥＣ）、エチルメチルカーボネート（ＥＭＣ）、ジプロピルカーボネート（ＤＰＣ）等の鎖状カーボネート類、ギ酸メチル、酢酸メチル、プロピオン酸エチル等の脂肪族カルボン酸エステル類、γ-ブチロラクトン等のγ-ラクトン類、1,2-ジエトキシエタン、1-エトキシ-1-メトキシエタン等の鎖状エーテル類、テトラヒドロフラン、2-メチルテトラヒドロフラン等の環状エーテル類、ジメチルスルホキシド、1,3-ジオキソラン、ホルムアミド、アセトアミド、ジメチルホルムアミド、ジオキソラン、アセトニトリル、プロピルニトリル、ニトロメタン、エチルモノグライム、リン酸トリエステル、トリメトキシメタン、ジオキソラン誘導体、スルホラン、メチルスルホラン、1,3-ジメチル-2-イミダゾリジノン、3-メチル-2-オキサゾリジノン、プロピレンカーボネート誘導体、テトラヒドロフラン誘導体、エチルエーテル、1,3-プロパンサルトン、アニソール、Ｎ−メチルピロリドン、などの非プロトン性有機溶媒の一種又は二種以上を混合して使用し、これらの有機溶媒にリチウム塩を溶解させたものを用いることができる。
【０１４５】
リチウム塩としては、例えばＬｉＰＦ₆、ＬｉＡｓＦ₆、ＬｉＡｌＣｌ₄、ＬｉＣｌＯ₄、ＬｉＢＦ₄、ＬｉＳｂＦ₆、ＬｉＣＦ₃ＳＯ₃、ＬｉＣＦ₃ＣＯ₂、Ｌｉ（ＣＦ₃ＳＯ₂）₂、ＬｉＮ（ＣＦ₃ＳＯ₂）₂、ＬｉＢ₁₀Ｃｌ₁₀、低級脂肪族カルボン酸カルボン酸リチウム、クロロボランリチウム、四フェニルホウ酸リチウム、ＬｉＢｒ、ＬｉＩ、ＬｉＳＣＮ、ＬｉＣｌ、イミド類などがあげられる。
【０１４６】
また、電解液に代えてポリマー電解質を用いてもよい。これら固体電解質に用いられる高分子物質としては、ポリフッ化ビニリデン、フッ化ビニリデン−ヘキサフルオロプロピレン共重合体、フッ化ビニリデン−エチレン共重合体、フッ化ビニリデン−モノフルオロエチレン共重合体、フッ化ビニリデン−トリフルオロエチレン共重合体、フッ化ビニリデン−テトラフルオロエチレン共重合体、フッ化ビニリデン−ヘキサフルオロプロピレン−テトラフルオロエチレン三元共重合体等のフッ化ビニリデン系重合体や、アクリロニトリル−メチルメタクリレート共重合体、アクリロニトリル−メチルアクリレート共重合体、アクリロニトリル−エチルメタクリレート共重合体、アクリロニトリル−エチルアクリレート共重合体、アクリロニトリル−メタクリル酸共重合体、アクリロニトリル−アクリル酸共重合体、アクリロニトリル−ビニルアセテート共重合体等のアクリロニトリル系重合体、さらにポリエチレンオキサイド、エチレンオキサイド−プロピレンオキサイド共重合体、これらのアクリレート体やメタクリレート体の重合体などが挙げられる。これらの高分子物質に電解液を含ませてゲル状にしたものを用いることができ、また高分子物質のみをそのまま用いても良い。
【０１４７】
〔正極の製造方法〕
本発明では、正極の製造方法については特に限定されず、従来公知の方法を採用することができる。例えば、正極の構成材料に溶剤を加えスラリー状にして電極集電体に塗布する方法、正極の構成材料にバインダー樹脂を加えて圧力をかけて固める方法、正極の構成材料に熱をかけて焼き固める方法などが挙げられる。
【０１４８】
〔電極の積層形態〕
本発明では、正極および負極の積層形態についても特に限定されるものではなく、任意の積層形態を採用することができ、多層積層体、集電体の両面に積層したものを組み合わせた形態、さらにこれらを巻回した形態とすることができる。
【０１４９】
〔電池の形状〕
本発明の電池の形状および外観については特に限定されるものではなく、従来公知のものを採用することができる。すなわち、このような電池形状としては、例えば、電極積層体または巻回体を、金属ケース、樹脂ケース、もしくはアルミニウム箔などの金属箔と合成樹脂フィルムとからなるラミネートフィルム等によって封止したものが挙げられる。また、電池の外観としては、円筒型、角型、コイン型、シート型等が挙げられる。
【０１５０】
【実施例】
以下、本発明を実施例により具体的に説明するが、本発明は、これらの実施例により制限されるものではない。
【０１５１】
（実施例１、比較例１及び２）
非水電解液二次電池の正極は次の手順で作製した。化学式（７）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物２５ｍｇと、グラファイト粉末２００ｍｇ、ポリテトラフルオロエチレン樹脂バインダー２５ｍｇを測り採り、メノウ乳鉢で混合した。１０分ほど乾式混合して得られた混合体を、圧力を掛けてローラー延伸して、厚さ２１５μｍの薄型電極板を得た。この薄型電極板を、真空中８０℃で一晩乾燥した後、直径１２ｍｍの円形に打ち抜いて正極成形体を得た。
【０１５２】
図１に示す非水電解液二次電池の負極を次の手順で作製した。まず、集電体１として厚み１０μｍの銅箔を用い、この銅箔上に炭素負極層（第１負極層）２を堆積させた。この炭素負極層２は、結着材としてＮ−メチル−２−ピロリドンに溶解したポリフッ化ビニリデンと導電付与材とを黒鉛粉末に混合してペースト状にし、このペースト状物を集電体１上に塗布し、乾燥させて形成した。乾燥後、炭素負極層２を、プレス機を使い圧縮した。
【０１５３】
この炭素負極層２の上に酸化ホウ素からなる第２負極層３を真空蒸着法を用いて堆積させ、さらに真空蒸着法を用いてリチウムからなる第３負極層４を堆積させて負極を得た。
【０１５４】
次に、得られた正極成形体を電解液に浸して、電極成形体中の空隙に電解液を染み込ませた。
【０１５５】
この電解液としては、１ｍｏｌ／ｌのＬｉＰＦ₆電解質塩を含むエチレンカーボネート／ジエチルカーボネート混合溶液（混合比３：７（体積比））を用いた。
【０１５６】
図６に示すように、正極１５として電解液を含浸させた正極成形体を、正極集電体を兼ねた正極側コイン型電池ケース１６上に配置し、その上に同じく電解液を含浸させた多孔質フィルムセパレータ１４を積層した。さらにその上に負極１３を積層し、枠状の絶縁パッキン１２を設置した。その後に、負極側コイン型電池ケース１１（負極集電体も兼ねる）を重ね合わせた。得られた積層体に、かしめ機により圧力を加え、密閉型のコイン型電池を得た。
【０１５７】
比較例１として、図３に示す厚み１０μｍの銅箔からなる集電体１と黒鉛を主成分とする炭素負極層２とで構成した負極を用いた以外は、実施例１と同様にしてコイン型電池を作製した。この電池に含まれる炭素負極層２の構成材料の全質量は実施例１の電池に含まれる第１負極層２の構成材料の全質量と同じにした。
【０１５８】
比較例２として、リチウム箔からなる負極を用いた以外は（その際負極側コイン型電池ケースが負極集電体を兼ねる）、実施例１と同様にしてコイン型電池を作製した。
【０１５９】
上記実施例１の負極（図１の構造）を用いた電池と、比較例１及び２の電池について、充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。実施例１並びに比較例１及び２の初回充放電の結果を表１に示す。比較例１及び２の充放電効率がそれぞれ８５．７％、８１．８％であるのに対して、実施例１の充放電効率は９６．０％であり、この結果から実施例１の初回充放電効率が高いことがわかる。なお、実施例１、比較例１、２の平均放電電圧はそれぞれ３．３Ｖ、３．２Ｖ、３．４Ｖであった。
【０１６０】
また、充放電サイクル特性の評価結果を表１に示す。表１中の放電容量比は、１サイクルの放電容量（Ｃ１）を１００％としたとき、それに対する３００サイクルの放電容量（Ｃ３００）の比率を表す。実施例１では３００サイクル後も初回の容量の９０％以上を保持しており、比較例１と同等のサイクル特性を持つことが分かる。比較例２の３００サイクル後の放電容量は初回放電容量の２２．７％であった。
【０１６１】
本実施例および比較例の評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０１６２】
【表１】

【０１６３】
（実施例２、３）
本実施例では、厚み１０μｍの銅箔からなる集電体１と、ハードカーボンを主成分とする炭素負極層（第１負極層）２と、シリコンからなる第２負極層３と、金属リチウムからなる第３負極層４をこの順で積層して図１に示す負極を作製した。第２負極層３の形成は、実施例２ではＣＶＤ法で行い、実施例３ではスパッタリング法で行った。第３負極層４の形成はいずれの実施例においても真空蒸着法を用いた。
【０１６４】
これらの負極を用いた以外は、実施例１と同様にしてコイン型電池を作製した。
【０１６５】
本実施例２及び３の負極（図１の構造）をそれぞれ用いた電池について、充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。実施例２及び３の初回充放電の結果を表２に示す。実施例２及び３の充放電効率は９０％以上であり、この結果から実施例２及び３の初回充放電効率が十分高いことがわかる。なお、実施例２及び３の平均放電電圧はともに３．３Ｖであった。
【０１６６】
この結果から、第１負極層２にハードカーボンを主成分とする材料を用いても第２負極層３及び第３負極層４を形成した本発明の構成にすることにより充放電効率を改善できることが明らかとなった。
【０１６７】
また、充放電サイクル特性の結果を表２に示す。実施例２及び３では３００サイクル後も初回の容量の９０％以上を保持していることが分かる。
【０１６８】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０１６９】
【表２】

【０１７０】
（実施例４〜６）
本実施例では、厚み１０μｍの銅箔からなる集電体１と、ハードカーボンを主成分とする炭素負極層（第１負極層）２と、ＳｉＯ_x（0＜x≦2）（実施例４）あるいはＳｎＯ_x（0＜x≦2）（実施例５）あるいはＳｉとＳｎの混合物（実施例６）からなる第２負極層３と、リチウムアルミニウム合金からなる第３負極層４をこの順で積層して図１に示す負極を作製した。
【０１７１】
実施例４〜６の電池のそれぞれに含まれるハードカーボンを主成分に用いた炭素負極層２の構成材料の全質量は、実施例２、３の電池のそれぞれに含まれるハードカーボンを主成分に用いた負極層２の構成材料の全質量と同じにした。
【０１７２】
第２負極層３の形成は、実施例４のＳｉＯ_x膜、実施例５のＳｎＯ_x膜については蒸着法により形成した。実施例６のＳｉとＳｎの混合物からなる膜（ＳｉＳｎ膜）の形成は、ＳｉとＳｎをそれぞれ別のるつぼに入れ、レーザーを用いて蒸着する方法を用いた。その際、それぞれの蒸着量を、水晶振動子を用いて測定することにより、ＳｉとＳｎの比率を制御した。
【０１７３】
第３負極層４のリチウムアルミニウム合金中のリチウムとアルミニウムの比率はそれぞれ９８％、２％とした。このリチウムアルミニウム合金膜の形成は、リチウムとアルミニウムをそれぞれ別のるつぼに入れ、レーザーを用いて蒸着する方法を用いた。その際、それぞれの蒸着量を、水晶振動子を用いて測定することにより、リチウムとアルミニウムの比率を制御した。
【０１７４】
これらの負極を用いた以外は、実施例１と同様にしてそれぞれコイン型電池を作製した。
【０１７５】
本実施例４〜６の負極（図１の構造）をそれぞれ用いた電池について、充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。実施例４〜６の初回充放電の結果を表３に示す。実施例４〜６の充放電効率はいずれも９０％以上と高くなっており、第３負極層４としてリチウムアルミニウム合金を用いても充放電効率が改善されることが分かる。なお、実施例４、５及び６の平均放電電圧はそれぞれ３．２Ｖ、３．２Ｖ、３．３Ｖであった。
【０１７６】
また、充放電サイクル特性の結果を表３に示す。実施例４〜６では３００サイクル後も初回の容量の９０％以上を保持することが分かる。
【０１７７】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０１７８】
【表３】

【０１７９】
（実施例７）
本実施例では、厚み１０μｍの銅箔からなる集電体１と、黒鉛を主成分とする炭素負極層（第１負極層）２と、ＳｉＯ_x（0＜x≦2）からなる第２負極層３と、金属リチウムと窒化リチウムとの混合物膜からなる第３負極層４をこの順で積層して図１に示す負極を作製した。第２負極層３のＳｉＯ_x膜の形成は真空蒸着法を用いて行った。第３負極層４の混合物中の金属リチウムと窒化リチウムの比率はそれぞれ９０％、１０％とした。この混合物膜の形成は、金属リチウムと窒化リチウムをそれぞれ別のハーネスに入れ、レーザーを用いて蒸着する方法を用いた。
【０１８０】
この負極を用いた以外は、実施例１と同様にしてコイン型電池を作製した。
【０１８１】
本実施例の負極（図１の構造）を用いた電池について、充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。本実施例の初回充放電の結果を表４に示す。本実施例の充放電効率は９４％以上と十分高くなっており、第３負極層４として金属リチウムと窒化リチウムの混合物を用いても充放電効率が改善されることが明らかとなった。なお、本実施例の平均放電電圧は３．３Ｖであった。
【０１８２】
また、充放電サイクル特性の結果を表４に示す。本実施例では３００サイクル後も初回の容量の９０％以上を保持していることが分かる。
【０１８３】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０１８４】
【表４】

【０１８５】
（実施例８、９）
実施例８及び９の負極の構造をそれぞれ図４及び図５に示す。実施例８では、第３負極層４が上下から第２負極層３に挟まれた構造をとっている。実施例９では、第１負極層２が上下から第２負極層３に挟まれた構造をとっている。
【０１８６】
本実施例では、集電体１として厚み１０μｍの銅箔を用い、第１負極層２として黒鉛を主成分とする材料を用い、第２負極層３にはシリコンを用い、第３負極層４には金属リチウムを用いた。第２負極層３及び第３負極層４の形成には真空蒸着法を用いた。実施例８、９の電池にそれぞれ含まれる第１負極層２の構成材料の全質量は、実施例１の電池に含まれる炭素負極層２の構成材料の全質量と同じにした。
【０１８７】
これらの負極を用いた以外は、実施例１と同様にしてそれぞれコイン型電池を作製した。
【０１８８】
本実施例８及び９の負極をそれぞれ用いた電池について、充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。実施例８及び９の初回充放電の結果を比較例１及び２の結果とともに表５に示す。実施例８及び９の充放電効率はどちらも９０％以上と、比較例１及び２の充放電効率より高くなっており、充放電効率が改善されることが分かる。なお、実施例８及び９の平均放電電圧はいずれも３．３Ｖであった。
【０１８９】
また、充放電サイクル特性の結果を表５に示す。実施例８及び９では３００サイクル後も初回の容量の９０％以上を保持しており、比較例２より優れ、比較例１と同等以上のサイクル特性を持つことが分かる。
【０１９０】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０１９１】
【表５】

【０１９２】
（比較例３）
本比較例では、実施例１で用いた化学式（７）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物の代わりにＬｉＣｏＯ₂２５ｍｇを用いた以外は実施例１と同様にして正極を作製し、この正極を用いた以外は実施例１と同様にしてコイン型電池を作製した。
【０１９３】
この電池について充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。本比較例の初回充放電の結果を実施例１の結果とともに表６に示す。実施例１の充放電効率が９６．０％であるのに対して、本比較例の充放電効率は６４．６％と低く、この結果から、正極材料として化学式（７）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物を用いることにより、初回充放電効率が向上することがわかる。なお、比較例３の平均放電電圧は３．７Ｖであった。
【０１９４】
また、充放電サイクル特性の評価結果を表６に示す。本比較例の３００サイクル後の放電容量は初回放電容量の８７．９％であった。
【０１９５】
【表６】

【０１９６】
(実施例１０、１１)
本実施例では、実施例１で用いた化学式（７）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物の代わりに、実施例１０では化学式（８）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物２５ｍｇ、実施例１１では化学式（１０）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物２５ｍｇを用いた以外は実施例１と同様にして正極を作製し、この正極を用いた以外は実施例１と同様にしてそれぞれコイン型電池を作製した。
【０１９７】
これらの電池について充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。本実施例の初回充放電の結果及び充放電サイクル特性の評価結果を表７に示す。これらの実施例の充放電効率は９０％以上であり、この結果から、正極材料としてキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物を用いた正極と、炭素を主成分とする第一の層と、リチウムイオン導電性を持つ膜状材料を主成分とする第二の層と、Ｌｉからなる第三の層とを含む多層構造の負極を用いた電池は、初回充放電効率が高いことがわかる。なお、これらの実施例の平均放電電圧はそれぞれ３．１Ｖ、３．０Ｖであった。
【０１９８】
また、実施例１０、１１の３００サイクル後の放電容量はそれぞれ初回放電容量の９１．４％、９０．３％であった。
【０１９９】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０２００】
【表７】

【０２０１】
（実施例１２〜１６）
実施例１２の非水電解液二次電池の正極は次の手順で作製した。化学式（１２）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイドポリマー化合物４０ｍｇと、アセチレンブラック粉末１５ｍｇ、人造黒鉛粉末３６ｍｇ、スチレン−ブタジエンラテックスの４０質量％溶液１０ｍｇ、メチルセルロースの２質量％溶液２１２ｍｇ、水１ｍｌを混ぜ合わせ、この混合物をホモジナイザーを用いて均一化してスラリーを得た。このスラリー１５ｍｇをドクターブレード法によりアルミニウム箔表面に付与して薄膜とした。これを直径１２ｍｍの円形に打ち抜いて正極成形体を得た。
【０２０２】
実施例１２は、この正極成形体を正極として用いた以外は、実施例１と同様にしてコイン型電池を作製した。
【０２０３】
実施例１３〜１６は、実施例１２で用いた化学式（１２）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物の代わりに下記のキノンジイミン−Ｎ，Ｎ’−ジオキサイドポリマー化合物４０ｍｇを用いた以外は、実施例１２と同様にして正極を作製し、この正極を用いた以外は実施例１２と同様にしてそれぞれコイン型電池を作製した。
【０２０４】
実施例１３：化学式（１１）で示される化合物、
実施例１４：化学式（１５）で示される化合物、
実施例１５：化学式（１７）で示される化合物、
実施例１６：化学式（１８）で示される化合物。
【０２０５】
実施例１２〜１６の電池について充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．０Ｖとした。実施例１２〜１６の初回充放電の結果及び充放電サイクル特性の評価結果を表８に示す。実施例１２〜１６の充放電効率は９０％以上あるいは９０％に近い値であり、この結果から、正極材料としてキノンジイミン−Ｎ，Ｎ’−ジオキサイドポリマー化合物を用いた正極と、炭素を主成分とする第一の層と、リチウムイオン導電性を持つ膜状材料を主成分とする第二の層と、Ｌｉからなる第三の層とを含む多層構造の負極を用いた電池は、初回充放電効率が高いことがわかる。なお、実施例１２〜１６の平均放電電圧は、実施例１３では緩やかに電圧が下降したが、それ以外の実施例ではそれぞれ３．１Ｖ、３．１Ｖ、３．１Ｖ、３．２Ｖであった。
【０２０６】
また、実施例１２〜１６の３００サイクル後の放電容量はそれぞれ初回放電容量の９０．４％、８９．７％、９２．８％、９４．８％、９３．４％であった。
【０２０７】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０２０８】
【表８】

【０２０９】
(実施例１７〜１９)
本実施例では、実施例１で用いた化学式（７）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物の代わりに下記のポリアセン型ジアジン−Ｎ，Ｎ’−ジオキサイド化合物２５ｍｇを用いた以外は、実施例１と同様にして正極を作製し、この正極を用いた以外は実施例１と同様にしてそれぞれコイン型電池を作製した。
【０２１０】
実施例１７：化学式（２４）で示される化合物、
実施例１８：化学式（２３）で示される化合物、
実施例１９：化学式（２７）で示される化合物。
【０２１１】
実施例１７〜１９の電池について充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．５Ｖとした。実施例１７〜１９の初回充放電の結果及び充放電サイクル特性の評価結果を表９に示す。実施例１７〜１９の充放電効率はいずれも９０％以上であり、この結果から、正極材料としてポリアセン型ジアジン−Ｎ，Ｎ’−ジオキサイド化合物を用いた正極と、炭素を主成分とする第一の層と、リチウムイオン導電性を持つ膜状材料を主成分とする第二の層と、Ｌｉからなる第三の層とを含む多層構造の負極を用いた電池は、初回充放電効率が高いことがわかる。なお、実施例１７〜１９の平均放電電圧はそれぞれ３．９Ｖ、３．８Ｖ、３．７Ｖであった。
【０２１２】
また、実施例１７〜１９の３００サイクル後の放電容量はそれぞれ初回放電容量の９２．５％、９０．６％、９１．４％であった。
【０２１３】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０２１４】
【表９】

【０２１５】
(実施例２０〜２４)
本実施例では、実施例１で用いた化学式（７）で示されるキノンジイミン−Ｎ，Ｎ’−ジオキサイド化合物の代わりに下記の化合物２５ｍｇを用いた以外は、実施例１と同様にして正極を作製し、この正極を用いた以外は実施例１と同様にしてそれぞれコイン型電池を作製した。
【０２１６】
実施例２０：化学式（３１）で示される直鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドポリマー化合物、
実施例２１：化学式（３８）で示される側鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドポリマー化合物、
実施例２２：化学式（３９）で示される側鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドポリマー化合物、
実施例２３：化学式（４１）で示される側鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドポリマー化合物、
実施例２４：化学式（４３）で示される側鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドポリマー化合物。
【０２１７】
実施例２０〜２４の電池について充放電サイクル試験を行った。充放電試験の電圧範囲は２．５〜４．５Ｖとした。実施例２０〜２４の初回充放電の結果及び充放電サイクル特性の評価結果を表１０に示す。実施例２０〜２４の充放電効率はいずれも９０％以上であり、この結果から、正極材料として直鎖型および側鎖型ジアジン−Ｎ，Ｎ’−ジオキサイドポリマー化合物を用いた正極と、炭素を主成分とする第一の層と、リチウムイオン導電性を持つ膜状材料を主成分とする第二の層と、Ｌｉからなる第三の層とを含む多層構造のものを用いた電池の初回充放電効率が高いことがわかる。なお、実施例２０〜２４の平均放電電圧は３．９Ｖ、３．８Ｖ、３．９Ｖ、３．８Ｖ、３．７Ｖであった。
【０２１８】
また、実施例２０〜２４の３００サイクル後の放電容量はそれぞれ初回放電容量の９４．１％、９５．３％、９３．５％、９１．１％、９５．２％であった。
【０２１９】
本実施例における評価結果から、本発明に係る正極及び負極を備える二次電池は、容量および充放電効率が高く、かつサイクル特性も安定していることが証明された。
【０２２０】
【表１０】

【０２２１】
【発明の効果】
以上説明したように本発明によれば、正極活物質にＮ−オキシド化合物を含有し、負極の構造として、炭素を主成分とする第一の層と、リチウムイオン導電性を持つ膜状材料を主成分とする第二の層と、Ｌｉ又はＬｉ含有化合物を主成分とする第三の層とを含む多層構造を採用することによって、容量密度が高く（すなわちエネルギー密度が高く）、充放電効率が高く、サイクル特性に優れた二次電池が得られる。
【０２２２】
本発明において正極活物質に用いたＮ−オキシド化合物は、酸化還元の反応部位が局在しているため、高い容量密度を実現することができる。
【０２２３】
また本発明の構成によれば、負極の第三の層に含まれるＬｉが負極の不可逆容量を効率良く補填することができ、高い充放電効率と放電容量を両立させることができる。また第三の層に含まれるＬｉの一部は第二の層へドープされ、第二の層のリチウムイオン導電性を高くする。このような高いリチウムイオン導電性を持つ膜状材料が負極中に均一に存在することとなるため、正極と負極間の電界分布が均一になる。この結果、電界の局所的集中を防止し、良好なサイクル特性を実現できる。
【図面の簡単な説明】
【図１】本発明の二次電池における負極の断面構造の一例である。
【図２】本発明の二次電池における負極の断面構造の一例である。
【図３】比較例の二次電池における負極の断面構造の一例である。
【図４】本発明の二次電池における負極の断面構造の一例である。
【図５】本発明の二次電池における負極の断面構造の一例である。
【図６】本発明の二次電池の構成の一例である。
【符号の説明】
１ 集電体
２ 炭素負極層（第１負極層）
３ 第２負極層
４ 第３負極層
１１ 負極集電体
１２ 絶縁パッキン
１３ 負極
１４ セパレータ
１５ 正極
１６ 正極集電体[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a secondary battery using lithium.
[0002]
[Prior art]
With the widespread use of mobile terminals such as mobile phones and laptop computers, the role of secondary batteries that serve as the power source has become important. These secondary batteries are required to have a small size, a light weight, and a high capacity, which are resistant to deterioration even after repeated charging and discharging. In order to meet this demand, a secondary battery using an alkali metal ion such as lithium ion as a charge carrier and utilizing an electrochemical reaction accompanying charge transfer has been developed. Among these, lithium ion secondary batteries are used in various electronic devices as high-capacity secondary batteries having excellent stability and large energy density.
[0003]
Conventional lithium ion secondary batteries use lithium-containing transition metal oxides as the positive electrode active material and carbon as the negative electrode active material, and utilize the insertion and desorption reactions of lithium ions into these active materials. Charging and discharging.
[0004]
However, since this lithium ion secondary battery uses a metal oxide having a large molecular weight especially for the positive electrode, the secondary battery capacity per unit mass cannot be said to be sufficient, and an electrode material having a smaller molecular weight is used to achieve a high capacity. Attempts to develop secondary batteries have been considered.
[0005]
For example, Patent Document 1 (US Pat. No. 4,833,048) and Patent Document 2 (Japanese Patent No. 2715778) disclose secondary batteries using an organic compound having a disulfide bond as a positive electrode. . This utilizes the electrochemical redox reaction accompanied by the formation and dissociation of disulfide bonds as the principle of the secondary battery.
[0006]
However, since this secondary battery is composed of electrode materials mainly composed of elements with small atomic weight such as sulfur and carbon, it can show a certain effect in terms of a secondary battery with high energy density, but it is dissociated. The efficiency of recombination of the bonded bonds is small, and the stability in the charged or discharged state is insufficient.
[0007]
On the other hand, as a secondary battery using an organic compound, a secondary battery using a conductive polymer as an electrode material has been proposed. This is a secondary battery based on the principle of doping and dedoping of electrolyte ions with respect to a conductive polymer. The dope reaction described here is a reaction that stabilizes excitons such as charged solitons and polarons generated by oxidation or reduction of a conductive polymer with a counter ion. On the other hand, the de-doping reaction corresponds to the reverse reaction and indicates a reaction in which exciton stabilized by a counter ion is electrochemically oxidized or reduced. Patent Document 3 (US Pat. No. 4,442,187) discloses a secondary battery using such a conductive polymer as a positive electrode or negative electrode material. This secondary battery is composed only of elements having a small atomic weight such as carbon and nitrogen, and is expected to be developed as a high energy density secondary battery.
[0008]
However, the conductive polymer has a property that excitons generated by redox are delocalized over a wide range of the π-electron conjugated system and interact with each other. This places a limit on the concentration of excitons generated, and limits the energy density of the secondary battery. For this reason, the energy density is insufficient in a secondary battery using a conductive polymer as an electrode material.
[0009]
Moreover, a secondary battery using an N-oxide compound as an active material has been proposed as a secondary battery using an organic compound. Unlike conductive polymers, N-oxide compounds have a high capacity density and are expected as secondary battery materials because the oxidation-reduction reaction sites are localized. However, unlike lithium-containing transition metal oxides, N-oxide compounds do not contain electrolyte ions in the material. Therefore, a secondary battery using an N-oxide compound for the positive electrode and a conventional carbon material for the negative electrode has a problem that the battery capacity is dependent on the amount of mobile ions in the electrolyte and the battery energy density is reduced. In order to solve this problem, Japanese Patent Application No. 2001-307457 proposes a secondary battery using an N-oxide compound for the positive electrode and metallic lithium for the negative electrode, but using metallic lithium for the negative electrode. The secondary battery has insufficient cycle characteristics as described below.
[0010]
For the negative electrode of the secondary battery, metallic lithium is sometimes used from the viewpoint of high energy density and light weight. In this case, acicular crystals (dendrites) are formed on the lithium surface during charging as the charging / discharging cycle proceeds. There is a problem that the crystals are deposited, the crystal penetrates the separator, causes an internal short circuit, and the life of the battery is shortened.
[0011]
Further, as a negative electrode of a secondary battery, the composition formula is Li_X The use of a lithium alloy represented by A (A represents a metal such as Al) has been studied. Although this negative electrode has a large volume of lithium ion storage / release per unit volume, it expands and contracts when lithium ions are stored / released, so fine powdering progresses as the charge / discharge cycle progresses. To do. For this reason, there was a problem that the charge / discharge cycle life was short.
[0012]
On the other hand, when a carbon material such as graphite or hard carbon capable of occluding and releasing lithium ions is used as the negative electrode of the secondary battery, the charge / discharge cycle can be favorably repeated. Compared to the above, the capacity is small, and hard carbon has a large irreversible capacity in the first charge / discharge and low charge / discharge efficiency.
[0013]
Therefore, many studies have been made so far to improve the capacity and charge / discharge efficiency of the carbon negative electrode in the secondary battery.
[0014]
As a method for improving the capacity, for example, in Patent Document 4 (Japanese Patent Laid-Open No. 9-259868), aluminum, lead, and silver having a small particle size are supported on a carbon material as a Li ion occlusion / release aid in the negative electrode. Thus, a technology for increasing the capacity is disclosed.
[0015]
Patent Document 5 (Japanese Patent Application Laid-Open No. 7-326342) discloses a lithium secondary battery having, as an active material, a laminate in which a porous layer made of a Li alloy is formed on the surface of a carbon layer. A negative electrode is disclosed. It is described that this negative electrode can provide a lithium secondary battery having an excellent charge / discharge cycle life while having a large discharge capacity and a high electromotive force.
[0016]
For the purpose of preventing the deterioration of the negative electrode, Patent Document 6 (Japanese Patent Laid-Open No. 5-234583) proposes using a carbon material coated with aluminum as the negative electrode material. This prevents lithium ions from intercalating in a solvated state between carbon layers, and as a result, damage to the carbon layer can be prevented and rapid deterioration of cycle characteristics can be suppressed.
[0017]
On the other hand, as a method for improving the charge / discharge efficiency, for example, in Patent Document 7 (Japanese Patent Laid-Open No. 5-144473), a lithium-containing composite oxide is used for the positive electrode, and a carbon material is used for the negative electrode. In a non-aqueous electrolyte secondary battery wound in a spiral with a separator, it is disclosed that metal Li foil is attached to the outermost periphery of a negative electrode plate, and lithium is diffused into a carbon material by a potential difference or a concentration difference. . By this method, it is said that a non-aqueous electrolyte secondary battery having high energy density and excellent overdischarge characteristics can be obtained.
[0018]
Patent Document 8 (Japanese Patent Application Laid-Open No. 5-242911) discloses a component that is electrically connected to a negative electrode in a lithium ion secondary battery that includes a lithium-containing compound in the positive electrode and a carbon material in the negative electrode. Thus, it is disclosed that metal lithium is electrically connected in advance to a component other than the negative electrode active material when the battery is assembled. This is said to increase the energy density and improve the overdischarge characteristics.
[0019]
In Patent Document 9 (Japanese Patent Laid-Open No. 10-144295), a conductive metal (copper) that does not form an alloy with lithium is deposited on the surface of a carbon material that is a negative electrode active material. A secondary battery characterized by depositing metallic lithium is disclosed. As a result, lithium ions can be efficiently occluded in the negative electrode active material, the loss capacity in the negative electrode can be reliably compensated, the initial charge / discharge efficiency can be increased, the battery capacity can be increased, and the charge / discharge cycle can be further increased. It is said that the characteristics can be improved.
[0020]
Patent Document 10 (Japanese Patent Laid-Open No. 5-275077) discloses a negative electrode for a lithium secondary battery in which the surface of a carbon material used as a constituent element of the negative electrode is coated with a thin film of lithium ion conductive solid electrolyte. Yes. Thereby, it is said that a lithium secondary battery with improved discharge characteristics and cycle characteristics using a carbon material as a negative electrode and using propylene carbonate as at least a part of an organic solvent of an electrolytic solution can be provided.
[0021]
Patent Document 11 (Japanese Patent Application Laid-Open No. 2000-182602) aims to provide a safe non-aqueous secondary battery having excellent overcharge safety, high capacity, low cost and low liquid leakage. A negative electrode sheet comprising a positive electrode sheet containing a positive electrode active material containing manganese, a layer mainly composed of a negative electrode material containing an amorphous oxide or a carbon material, and an auxiliary layer containing water-insoluble particles. Discloses a non-aqueous secondary battery in which a metal foil mainly composed of lithium is attached.
[0022]
In Patent Document 12 (Republished Patent WO96 / 33519), it is an object to provide a non-aqueous secondary battery having a high discharge potential, a high capacity, good cycleability and storage stability and excellent safety. A non-aqueous secondary battery using an amorphous oxide containing at least one element selected from Sn, Mn, Fe, Pb, and Ge as a negative electrode material is disclosed.
[0023]
However, the technique for supporting aluminum having a small particle diameter on a carbon material disclosed in Patent Document 4 (Japanese Patent Laid-Open No. 9-259868) is difficult to uniformly disperse metal particles in the carbon material. The metal tends to localize in the negative electrode. As a result, when the charge / discharge cycle is repeated, the charge / discharge state of the electrode becomes non-uniform due to local concentration of the electric field, and the deformation of the electrode, the current from the current collector There was a problem that peeling occurred. For this reason, it has been difficult to maintain a high level of cycle characteristics.
[0024]
SnB disclosed in Patent Document 12 (Republished Patent WO96 / 33519)_xP_yO_z(X is 0.4 to 0.6, y is 0.6 to 0.4) The metal oxide amorphous material has a large irreversible capacity in the first charge and discharge, and it is difficult to sufficiently increase the energy density of the battery. Had problems.
[0025]
Furthermore, the above conventional technique has a common problem that a high operating voltage cannot be obtained. The reason is that, when a metal and a carbon-based material are mixed, a plateau peculiar to the metal is formed at a voltage higher than carbon in the discharge curve, so that the operating voltage is lower than when only carbon is used as the negative electrode. . Lithium secondary batteries have a lower limit voltage depending on their use. Therefore, when the operating voltage is lowered, the usable area is narrowed. As a result, it is difficult to increase the capacity in the area where the battery is actually used.
[0026]
On the other hand, the negative electrode material using aluminum disclosed in Patent Document 6 (Japanese Patent Laid-Open No. 5-234583) has a problem that the capacity rapidly decreases when the cycle is repeated. This is presumably because impurities such as water present in the electrolyte react with aluminum to form a thin insulating film on the aluminum surface.
[0027]
Further, a metal Li electrode is used for the carbon negative electrode disclosed in Patent Document 7 (Japanese Patent Laid-Open No. 5-144473), Patent Document 8 (Japanese Patent Laid-Open No. 5-242911), Patent Document 5 (Japanese Patent Laid-Open No. 7-326342), and the like. The charge / discharge efficiency is not improved sufficiently by mixing, adding, or sticking lithium or a lithium alloy. The reason is that when carbon and metal Li or lithium alloy are in direct contact, metal Li or lithium alloy reacts with active functional groups on the carbon surface or impurities such as adsorbed water to form a film on the carbon surface. . Lithium contained in such a film is electrochemically inactive and cannot contribute to the charge / discharge capacity of the battery. Therefore, in the above method, the improvement of the charge / discharge efficiency is insufficient. Furthermore, since these films have a large electric resistance, the resistance of the battery is increased, and the effective capacity of the battery is rather decreased.
[0028]
Patent Document 10 (Japanese Patent Laid-Open No. 5-275077) discloses a negative electrode for a lithium secondary battery in which the surface of a carbon material used as a constituent element of the negative electrode is coated with a thin film of lithium ion conductive solid electrolyte. However, since the negative electrode does not contain a lithium component in advance, the irreversible capacity during the first charge / discharge is large, and the charge / discharge efficiency is low.
[0029]
Patent Document 11 (Japanese Patent Laid-Open No. 2000-182602) discloses a negative electrode for a secondary battery in which a metal foil mainly composed of lithium is attached to a negative electrode sheet made of an amorphous oxide capable of inserting and extracting lithium. Although it is disclosed, what is specifically disclosed as an amorphous oxide negative electrode sheet is a structure in which an active material such as SnAlBPSiO is solidified with a binder. Such a sheet inevitably causes uneven metal distribution on a microscopic scale, resulting in local concentration of the electric field. Further, when the binder comes into direct contact with the lithium metal foil, a part of the binder and the lithium metal foil reacts to form a highly resistant film. For these reasons, it has been difficult to maintain a high level of cycle characteristics.
[0030]
As described above, various secondary batteries have been proposed, but a secondary battery with high energy density and excellent cycle characteristics has not been obtained yet.
[0031]
[Patent Document 1]
US Pat. No. 4,833,048
[Patent Document 2]
Japanese Patent No. 2715778
[Patent Document 3]
U.S. Pat. No. 4,442,187
[Patent Document 4]
JP-A-9-259868
[Patent Document 5]
JP 7-326342 A
[Patent Document 6]
Japanese Patent Laid-Open No. 5-234583
[Patent Document 7]
JP-A-5-144473
[Patent Document 8]
JP-A-5-242911
[Patent Document 9]
Japanese Patent Laid-Open No. 10-144295
[Patent Document 10]
JP-A-5-275077
[Patent Document 11]
JP 2000-182602 A
[Patent Document 12]
Republished Patent WO96 / 33519
[0032]
[Problems to be solved by the invention]
An object of the present invention is to provide a secondary battery having a high energy density and good cycle characteristics in view of the above-described problems of the prior art.
[0033]
[Means for Solving the Problems]
According to the present invention for solving the above problems, the following secondary battery is provided.
[0034]
According to the present invention, in a secondary battery including at least a positive electrode, a negative electrode, and an electrolyte, the positive electrode is represented by the following general formula (1) as a positive electrode active material.
[0035]
[Chemical 6]

[0036]
Containing an N-oxide compound having a partial structure represented by
  The negative electrode includes a first layer mainly composed of carbon,Different material than the first layer,Capable of occluding and releasing lithium componentsLithium ion conductivityA second layer of material,Metallic lithium, lithium alloy, lithium nitride, Li _3-x M _x It consists of one or more selected from N (M = Co, Ni, Cu)A secondary battery comprising a third layer and having a multilayer structure in which a second layer is disposed between the first layer and the third layer is provided.
[0037]
DETAILED DESCRIPTION OF THE INVENTION
In the secondary battery according to the present invention, the following configuration can be adopted.
[0038]
[Configuration of positive electrode]
The positive electrode of the secondary battery of the present invention contains an N-oxide compound having a partial structure represented by the following general formula (1) in the molecule as an essential positive electrode active material.
[0039]
[Chemical 7]

[0040]
As a suitable example of the N-oxide compound having a partial structure represented by the general formula (1) in the molecule, an N-oxide compound having a partial structure represented by the following general formula (2) in the molecule (hereinafter referred to as “quinonediimine— N, N'-dioxide compound ").
[0041]
[Chemical 8]

[0042]
In the general formula (2), R₁~ R_FourEach independently represents a hydrogen atom, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted cycloalkyl group Substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or unsubstituted alkoxy group, substituted or unsubstituted A substituted aryloxy group, a substituted or unsubstituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted acyl group, or a substituted or unsubstituted acyloxy group is shown. In addition, one or more atoms of these substituents may be substituted with a sulfur atom, a silicon atom, a phosphorus atom, or a boron atom, and the substituents may form a ring structure.
[0043]
Moreover, as a suitable example of the N-oxide compound having a partial structure represented by the general formula (1) in the molecule, an N-oxide compound having a partial structure represented by the following general formula (3) or (4) in the molecule Is mentioned.
[0044]
[Chemical 9]

[0045]
In the general formula (3), R₁~ R₈Each independently represents a hydrogen atom, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted cycloalkyl group Substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or unsubstituted alkoxy group, substituted or unsubstituted A substituted aryloxy group, a substituted or unsubstituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted acyl group, or a substituted or unsubstituted acyloxy group is shown. In addition, one or more atoms of these substituents may be substituted with a sulfur atom, a silicon atom, a phosphorus atom, or a boron atom, and the substituents may form a ring structure.
[0046]
Embedded image

[0047]
In the general formula (4), R₁~ R₈Each independently represents a hydrogen atom, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted cycloalkyl group Substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or unsubstituted alkoxy group, substituted or unsubstituted A substituted aryloxy group, a substituted or unsubstituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted acyl group, or a substituted or unsubstituted acyloxy group is shown. In addition, one or more atoms of these substituents may be substituted with a sulfur atom, a silicon atom, a phosphorus atom, or a boron atom, and the substituents may form a ring structure.
[0048]
The N-oxide compound having a partial structure represented by the general formulas (1) to (4) in the molecule may be a low molecular compound, an oligomer, or a polymer compound. In the case of a polymer compound, the shape may be a chain, a branch, or a network.
[0049]
Examples of other N-oxide compounds having a partial structure represented by the general formula (1) in the molecule include compounds having a structure represented by the following general formula (5). For example, pyrazine compounds (n + m + n ′ + m Which satisfy '= 0), polyacene-type diazine-N, N′-dioxide compounds (which satisfy n + m + n ′ + m ′ ≧ 1), these pyrazine compounds or polyacene-type diazine-N, N′-dioxide compounds An oligomer or polymer compound having a divalent group having two bonds in the condensed ring as a structural unit (hereinafter, these compounds are referred to as “linear diazine-N, N′-dioxide oligomer or polymer compound”), or One bond is attached to the condensed ring of the pyrazine compound or the polyacene type diazine-N, N′-dioxide compound. One oligomeric or polymeric compounds having a structural unit having a monovalent group (hereinafter these compounds "side chain type diazine -N, N'-dioxide oligomeric or polymeric compound" hereinafter) may also be mentioned.
[0050]
Embedded image

[0051]
In the general formula (5), n, m, n ′ and m ′ each independently represent an integer of 0 or more. Further, the order of condensation of the diazine ring and the benzene ring may be alternate or random. R₁, R₂, R_Three, R_Four, R^a, R^b, R^cAnd R^dOne or two of them may be the above bond, and the remaining substituent in that case, and in the case of not having a bond, all the substituents are independently a hydrogen atom, a halogen atom, Hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted cycloalkyl group, substituted or unsubstituted aromatic hydrocarbon group Substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted Alkoxycarbonyl group, substituted or unsubstituted aryloxycarbonyl group, substituted or unsubstituted acyl group, or substituted Represents an unsubstituted acyloxy group. However, when n is 2 or more, R^aAnd R^bMay be the same or different, and when n 'is 2 or more, R'^cAnd R^dMay be the same or different. In addition, one or more atoms of these substituents may be substituted with a sulfur atom, a silicon atom, a phosphorus atom, or a boron atom, and the substituents may form a ring structure.
[0052]
In the general formulas (2) to (5), the substituent R₁, R₂, R_Three, R_Four, R_Five, R₆, R₇, R₈, R^a, R^b, R^cAnd R^dExamples of the halogen atom include fluorine, chlorine, bromine, iodine and the like, and they can be used singly or in combination of two or more.
[0053]
Examples of the substituted or unsubstituted alkyl group include a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, t-butyl group, n-pentyl group, n- Hexyl group, n-heptyl group, n-octyl group, hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group, 2-hydroxyisobutyl group, 1,2-dihydroxyethyl group, 1,3-dihydroxyisopropyl group 2,3-dihydroxy-t-butyl group, 1,2,3-trihydroxypropyl group, chloromethyl group, 1-chloroethyl group, 2-chloroethyl group, 2-chloroisobutyl group, 1,2-dichloroethyl group 1,3-dichloroisopropyl group, 2,3-dichloro-t-butyl group, 1,2,3-trichloropropyl group, bromomethyl Group, 1-bromoethyl group, 2-bromoethyl group, 2-bromoisobutyl group, 1,2-dibromoethyl group, 1,3-dibromoisopropyl group, 2,3-dibromo-t-butyl group, 1,2, 3-tribromopropyl group, iodomethyl group, 1-iodoethyl group, 2-iodoethyl group, 2-iodoisobutyl group, 1,2-diiodoethyl group, 1,3-diiodoisopropyl group, 2,3-diiodo-t- Butyl group, 1,2,3-triiodopropyl group, aminomethyl group, 1-aminoethyl group, 2-aminoethyl group, 2-aminoisobutyl group, 1,2-diaminoethyl group, 1,3-diaminoisopropyl Group, 2,3-diamino-t-butyl group, 1,2,3-triaminopropyl group, cyanomethyl group, 1-cyanoethyl group, 2-cyanoethyl group, 2-silane Noisobutyl group, 1,2-dicyanoethyl group, 1,3-dicyanoisopropyl group, 2,3-dicyano-t-butyl group, 1,2,3-tricyanopropyl group, nitromethyl group, 1-nitroethyl group, 2-nitroethyl group, 2-nitroisobutyl group, 1,2-dinitroethyl group, 1,3-dinitroisopropyl group, 2,3-dinitro-t-butyl group, 1,2,3-trinitropropyl group, etc. It can be mentioned, and it can have 1 type individually or in combination of 2 or more types.
[0054]
Examples of the substituted or unsubstituted alkenyl group include a vinyl group, allyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1,3-butanedienyl group, 1-methylvinyl group, styryl group, 2,2-diphenylvinyl group, 1,2-diphenylvinyl group, 1-methylallyl group, 1,1-dimethylallyl group, 2-methylallyl group, 1-phenylallyl group, 2-phenylallyl group, 3-phenylallyl Group, 3,3-diphenylallyl group, 1,2-dimethylallyl group, 1-phenyl-1-butenyl group, 3-phenyl-1-butenyl group and the like, and have one kind alone or in combination of two or more kinds. be able to.
[0055]
Examples of the substituted or unsubstituted cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 4-methylcyclohexyl group, and the like, which can be used singly or in combination of two or more. .
[0056]
Examples of the substituted or unsubstituted aromatic hydrocarbon group include a phenyl group, 1-naphthyl group, 2-naphthyl group, 9-fluorenyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1 -Phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 1-pyrenyl group, 2-pyrenyl group, 4 -Pyrenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl Group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-tolyl group, m-tolyl group, -Tolyl group, pt-butylphenyl group, p- (2-phenylpropyl) phenyl group, 3-methyl-2-naphthyl group, 4-methyl-1-naphthyl group, 4-methyl-1-anthryl group, Examples thereof include a 4′-methylbiphenylyl group, a 4 ″ -t-butyl-p-terphenyl-4-yl group, and derivatives thereof, and these can be used singly or in combination of two or more.
[0057]
Examples of the substituted or unsubstituted aromatic heterocyclic group include 1-pyrrolyl group, 2-pyrrolyl group, 3-pyrrolyl group, pyrazinyl group, 2-pyridinyl group, 3-pyridinyl group, 4-pyridinyl group, and 1-indolyl group. Group, 2-indolyl group, 3-indolyl group, 4-indolyl group, 5-indolyl group, 6-indolyl group, 7-indolyl group, 1-isoindolyl group, 2-isoindolyl group, 3-isoindolyl group, 4-isoindolyl group Group, 5-isoindolyl group, 6-isoindolyl group, 7-isoindolyl group, 2-furyl group, 3-furyl group, 2-benzofuranyl group, 3-benzofuranyl group, 4-benzofuranyl group, 5-benzofuranyl group, 6-benzofuranyl group Group, 7-benzofuranyl group, 1-isobenzofuranyl group, 3-isobenzofuranyl group, 4-isoben Furanyl group, 5-isobenzofuranyl group, 6-isobenzofuranyl group, 7-isobenzofuranyl group, 2-quinolyl group, 3-quinolyl group, 4-quinolyl group, 5-quinolyl group, 6-quinolyl Group, 7-quinolyl group, 8-quinolyl group, 1-isoquinolyl group, 3-isoquinolyl group, 4-isoquinolyl group, 5-isoquinolyl group, 6-isoquinolyl group, 7-isoquinolyl group, 8-isoquinolyl group, 2-quinoxalinyl Group, 5-quinoxalinyl group, 6-quinoxalinyl group, 1-carbazolyl group, 2-carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, 9-carbazolyl group, 1-phenanthridinyl group, 2-phenanthridinyl group Group, 3-phenanthridinyl group, 4-phenanthridinyl group, 6-phenanthridinyl group, 7-phenanthridinyl group, -Phenanthridinyl group, 9-phenanthridinyl group, 10-phenanthridinyl group, 1-acridinyl group, 2-acridinyl group, 3-acridinyl group, 4-acridinyl group, 9-acridinyl group, 1, 7-phenanthrolin-2-yl group, 1,7-phenanthrolin-3-yl group, 1,7-phenanthrolin-4-yl group, 1,7-phenanthrolin-5-yl group, 1,7-phenanthrolin-6-yl group, 1,7-phenanthrolin-8-yl group, 1,7-phenanthrolin-9-yl group, 1,7-phenanthrolin-10-yl group Group, 1,8-phenanthroline-2-yl group, 1,8-phenanthrolin-3-yl group, 1,8-phenanthrolin-4-yl group, 1,8-phenanthrolin-5 -Yl group, 1,8-phenanthroline-6- Yl group, 1,8-phenanthroline-7-yl group, 1,8-phenanthrolin-9-yl group, 1,8-phenanthrolin-10-yl group, 1,9-phenanthroline- 2-yl group, 1,9-phenanthrolin-3-yl group, 1,9-phenanthrolin-4-yl group, 1,9-phenanthrolin-5-yl group, 1,9-phenance Lorin-6-yl group, 1,9-phenanthrolin-7-yl group, 1,9-phenanthrolin-8-yl group, 1,9-phenanthrolin-10-yl group, 1,10- Phenanthrolin-2-yl group, 1,10-phenanthrolin-3-yl group, 1,10-phenanthrolin-4-yl group, 1,10-phenanthrolin-5-yl group, 2, 9-phenanthrolin-1-yl group, 2,9-phenanthrolin-3-yl group, , 9-phenanthrolin-4-yl group, 2,9-phenanthrolin-5-yl group, 2,9-phenanthrolin-6-yl group, 2,9-phenanthrolin-7-yl group 2,9-phenanthrolin-8-yl group, 2,9-phenanthrolin-10-yl group, 2,8-phenanthrolin-1-yl group, 2,8-phenanthrolin-3- Yl group, 2,8-phenanthroline-4-yl group, 2,8-phenanthrolin-5-yl group, 2,8-phenanthrolin-6-yl group, 2,8-phenanthrolin- 7-yl group, 2,8-phenanthrolin-9-yl group, 2,8-phenanthrolin-10-yl group, 2,7-phenanthrolin-1-yl group, 2,7-phenance Lorin-3-yl group, 2,7-phenanthrolin-4-yl group, 2,7-phenane Lorin-5-yl group, 2,7-phenanthrolin-6-yl group, 2,7-phenanthrolin-8-yl group, 2,7-phenanthrolin-9-yl group, 2,7- Phenanthrolin-10-yl group, 1-phenazinyl group, 2-phenazinyl group, 1-phenothiazinyl group, 2-phenothiazinyl group, 3-phenothiazinyl group, 4-phenothiazinyl group, 10-phenothiazinyl group, 1 -Phenoxazinyl group, 2-phenoxazinyl group, 3-phenoxazinyl group, 4-phenoxazinyl group, 10-phenoxazinyl group, 2-oxazolyl group, 4-oxazolyl group, 5-oxazolyl group, 2-oxadiazolyl group, 5-oxadiazolyl group, 3 -Flazanyl group, 2-thienyl group, 3-thienyl group, 2-methylpyrrol-1-yl group, 2-methylpyrrole -3-yl group, 2-methylpyrrol-4-yl group, 2-methylpyrrol-5-yl group, 3-methylpyrrol-1-yl group, 3-methylpyrrol-2-yl group, 3-methylpyrrole -4-yl group, 3-methylpyrrol-5-yl group, 2-t-butylpyrrol-4-yl group, 3- (2-phenylpropyl) pyrrol-1-yl group, 2-methyl-1-indolyl Group, 4-methyl-1-indolyl group, 2-methyl-3-indolyl group, 4-methyl-3-indolyl group, 2-t-butyl-1-indolyl group, 4-t-butyl-1-indolyl group , 2-t-butyl-3-indolyl group, 4-t-butyl-3-indolyl group, and derivatives thereof, and the like can be used alone or in combination of two or more.
[0058]
Examples of the substituted or unsubstituted aralkyl group include benzyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenylisopropyl group, 2-phenylisopropyl group, phenyl-t-butyl group, α-naphthyl. Methyl group, 1-α-naphthylethyl group, 2-α-naphthylethyl group, 1-α-naphthylisopropyl group, 2-α-naphthylisopropyl group, β-naphthylmethyl group, 1-β-naphthylethyl group, 2 -Β-naphthylethyl group, 1-β-naphthylisopropyl group, 2-β-naphthylisopropyl group, 1-pyrrolylmethyl group, 2- (1-pyrrolyl) ethyl group, p-methylbenzyl group, m-methylbenzyl group, o-methylbenzyl group, p-chlorobenzyl group, m-chlorobenzyl group, o-chlorobenzyl group, p-bromobenzyl group, m Bromobenzyl group, o-bromobenzyl group, p-iodobenzyl group, m-iodobenzyl group, o-iodobenzyl group, p-hydroxybenzyl group, m-hydroxybenzyl group, o-hydroxybenzyl group, p-aminobenzyl Group, m-aminobenzyl group, o-aminobenzyl group, p-nitrobenzyl group, m-nitrobenzyl group, o-nitrobenzyl group, p-cyanobenzyl group, m-cyanobenzyl group, o-cyanobenzyl group, A 1-hydroxy-2-phenylisopropyl group, a 1-chloro-2-phenylisopropyl group and the like can be mentioned, and these can be used alone or in combination of two or more.
[0059]
The substituted or unsubstituted amino group is -NX¹X²A substituent represented by X¹And X²Each independently represents, for example, a hydrogen atom, the above substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted Or an unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aralkyl group, etc. are mentioned, It can have these single 1 type or in combination of 2 or more types.
[0060]
In addition, a substituted or unsubstituted alkoxy group and a substituted or unsubstituted alkoxycarbonyl group are each -OX^ThreeAnd -COOX^FourA substituent represented by X^ThreeAnd X^FourEach includes, for example, the above-mentioned substituted or unsubstituted alkyl group, substituted or unsubstituted cycloalkyl group, substituted or unsubstituted aralkyl group, and the like, having one kind alone or a combination of two or more kinds. Can do.
[0061]
In addition, a substituted or unsubstituted aryloxy group and a substituted or unsubstituted aryloxycarbonyl group are each -OX^FiveAnd -COOX⁶A substituent represented by X^FiveAnd X⁶Examples of these include, for example, the above-mentioned substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups, and the like, and these can be used singly or in combination of two or more.
[0062]
In addition, a substituted or unsubstituted acyl group and a substituted or unsubstituted acyloxy group are each represented by —C (═O) X⁷And -OC (= O) X⁸A substituent represented by X⁷And X⁸As, for example, a hydrogen atom, the above-mentioned substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted An aromatic heterocyclic group, a substituted or unsubstituted aralkyl group and the like can be mentioned, and these can be used alone or in combination of two or more.
[0063]
Examples of the divalent group that forms a ring include a tetramethylene group, a pentamethylene group, a hexamethylene group, a diphenylmethane-2,2′-diyl group, a diphenylethane-3,3′-diyl group, and a diphenylpropane-4. , 4′-diyl group, 1,3-butadiene-1,4-diyl group, and derivatives thereof.
[0064]
In the above-described substituent, one or more atoms thereof may be substituted with a sulfur atom, a silicon atom, a phosphorus atom, or a boron atom. Examples of the group substituted with a sulfur atom include the oxygen atom of an oxygen-containing group such as the hydroxyl group, carboxyl group, alkoxy group, alkoxycarbonyl group, aryloxy group, aryloxycarbonyl group, acyl group, and acyloxy group described above. Mention may be made of substituents substituted by sulfur atoms. Examples of the substituent include mercapto group, dithiocarboxyl group, hydroxy (thiocarbonyl) group, mercaptocarbonyl group, methylthio group, methoxythiocarbonyl group, methylthiocarbonyl group, methyldithiocarboxyl group, phenylthio group, phenoxythiocarbonyl group , Phenylthiocarbonyl group, phenyldithiocarbonyl group, methylthiocarbonyl group, phenylthiocarbonyl group, and the like. Examples of the group substituted with a silicon atom include a substituent in which a carbon atom of the aforementioned alkyl group, alkenyl group, cycloalkyl group, or aralkyl group is replaced with a silicon atom. Examples of the substituent include silyl group, methylsilyl group, silylmethyl group, ethylsilyl group, (methylsilyl) methyl group, dimethylsilyl group, trimethylsilyl group, t-butyldimethylsilyl group, triisopropylsilyl group, and the like. Examples of the group substituted with a phosphorus atom include a substituent in which the nitrogen atom of the amino group is replaced with a phosphorus atom. Examples of the substituent include a phosphino group, a trimethylphosphino group, a triphenylphosphino group, and the like. Examples of the group substituted with a boron atom include a substituent in which the nitrogen atom of the amino group is replaced with a phosphorus atom. Examples of the substituent include a dimethylboryl group and a diphenylboryl group.
[0065]
Specific examples of the N-oxide compound are shown below, but are not limited thereto.
[0066]
Specific examples of the quinonediimine-N, N′-dioxide compound include compounds represented by the following chemical formulas (6) to (18). In these formulas, when there are n, m, and o, each represents an integer of 2 or more.
[0067]
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[0068]
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[0069]
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[0070]
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[0071]
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[0072]
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[0073]
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[0074]
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[0075]
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[0076]
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[0077]
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[0078]
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[0079]
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[0080]
The quinonediimine-N, N′-dioxide compound in the present invention includes a compound having a p-phenylenediamine structure represented by the general formula (19) as a partial structure, such as hydrogen peroxide, t-butyl hydroperoxide, benzoyl peroxide, etc. It can be obtained by oxidation with an organic peracid such as peroxyacetic acid, peracetic acid, perbenzoic acid, m-chloroperbenzoic acid, or an oxidizing agent such as peroxosulfuric acid. In addition, a compound having a p-phenylenediamine structure represented by the general formula (19) as a partial structure is oxidized with an oxidizing agent such as silver oxide, lead oxide, lead acetate, iron (III) chloride, potassium hexacyanoferrate (III). Oxidized into a compound having a p-quinonediimine structure represented by the general formula (20) as a partial structure, and this is further converted into an organic peroxide such as hydrogen peroxide, t-butyl hydroperoxide, benzoyl peroxide, peracetic acid, It can be obtained by oxidizing with an organic peracid such as perbenzoic acid or m-chloroperbenzoic acid, or an oxidizing agent such as peroxosulfuric acid. Further, a compound having a p-quinonediimine structure represented by the general formula (20) as a partial structure is converted to an organic peroxide such as hydrogen peroxide, t-butyl hydroperoxide, benzoyl peroxide, peracetic acid, perbenzoic acid, m It can be obtained by oxidizing with an organic peracid such as chloroperbenzoic acid or an oxidizing agent such as peroxosulfuric acid.
[0081]
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[0082]
(In the general formula (19), R¹~ R^FourEach independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted Aralkyl group, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted amino group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or non-substituted A substituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted acyloxy group)
[0083]
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[0084]
(In the general formula (20), R¹~ R^FourEach independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted Aralkyl group, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted amino group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or non-substituted A substituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted acyloxy group)
R in general formulas (19) and (20)¹~ R^FourExamples thereof include those exemplified as the substituents of the general formulas (2) to (5).
[0085]
C. J. et al. In CJPedersen, Journal of the American Chemical Society, pages 2295-2299 (1957), N, N′-diphenyl-p-quinonediimine-N , N′-dioxide (chemical formula (6)), N, N′-dicyclohexyl-p-quinonediimine-N, N′-dioxide (chemical formula (8)) and the like are described. According to this, N, N′-diphenyl-p-quinonediimine-N, N′-dioxide is made from N, N′-diphenyl-p-phenylenediamine as a raw material, oxidized with benzoyl peroxide, , N′-diphenyl-p-quinonediimine, which can be obtained by further oxidation with perbenzoic acid. N, N′-dicyclohexyl-p-quinonediimine-N, N′-dioxide can be obtained by using N, N′-dicyclohexyl-p-phenylenediamine as a raw material and oxidizing it with perbenzoic acid. it can.
[0086]
Specific examples of the pyrazine compound and the polyacene type diazine-N, N′-dioxide compound include compounds represented by the following chemical formulas (21) to (29).
[0087]
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[0088]
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[0089]
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[0090]
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[0091]
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[0092]
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[0093]
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[0094]
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[0095]
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[0096]
Specific examples of the linear diazine-N, N′-dioxide oligomer or polymer compound include compounds represented by the following chemical formulas (30) to (37). In these formulas, n represents an integer of 2 or more.
[0097]
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[0098]
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[0099]
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[0100]
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[0101]
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[0102]
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[0103]
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[0104]
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[0105]
Specific examples of the side chain type diazine-N, N′-dioxide oligomer or polymer compound include compounds represented by the following chemical formulas (38) to (44). In these formulas, n and m each represent an integer of 2 or more.
[0106]
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[0107]
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[0108]
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[0109]
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[0110]
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[0111]
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[0112]
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[0113]
The diazine N, N′-dioxide compound in the present invention can be produced by a known synthesis method such as oxidation of the corresponding diazine compound with a peroxide or a peracid.
[0114]
As a method for synthesizing a pyrazine compound and a polyacene-type diazine-N, N′-dioxide compound, for example, a method using urea peroxide is Sinlet, September 1990, pages 533 to 535 (Synlett, P533-535, September 1990). )It is described in. In the case of the compound represented by the chemical formula (23), a dichloromethane solution of metachloroperbenzoic acid is added to a dichloromethane solution of phenazine and stirred at room temperature, and then neutralized by adding a saturated aqueous solution of sodium carbonate. It can be obtained by purification according to the method.
[0115]
The linear diazine-N, N′-dioxide oligomer or polymer compound can be produced, for example, as follows. It can be obtained by reacting a linear diazine oligomer or polymer compound with a peroxide and N-oxidizing a nitrogen atom in the condensed ring. As another method, a dihalide compound in which two of the substituents of the condensed ring of the polyacene type diazine N, N′-dioxide compound are halogen is dehalogenated by adding a zero-valent nickel compound in an organic solvent. Can be obtained.
[0116]
The oligomer or polymer compound having a side chain type diazine N, N′-dioxide structure in the side chain is oligomerized or polymerized by, for example, radical polymerization of an olefin substituted with the corresponding diazine derivative, and this is converted into a peroxide. Alternatively, it can be produced by a known synthesis method such as oxidation using peracid. For example, for the synthesis method of poly (2-vinylpyrazine-N, N′-dioxide), Iranian Journal of Science and Technology, 1987, Vol. 11, No. 1, 27-34. (Iranian Journal of Science & Technology, P.27-34, Vol.11, No.1, 1987).
[0117]
In the secondary battery of the present invention, the positive electrode active material may be in a solid state or may be dissolved or dispersed in an electrolyte. However, when used in a solid state, in order to prevent a decrease in capacity due to dissolution in the electrolytic solution, those that are insoluble or have low solubility in the electrolytic solution are preferable.
[0118]
The oligomer or polymer of the N-oxide compound in the present invention may be a homopolymer polymerized only from a monomer having an N-oxide structure, or may be a copolymer with another monomer.
[0119]
In the positive electrode of the secondary battery of the present invention, the N-oxide compound which is an active material can be used alone, or two or more kinds may be used in combination. Moreover, you may use in combination with other positive electrode active materials, such as a metal oxide particle, a disulfide compound, and a conductive polymer. As a metal oxide, LiMnO₂, Li_xMn₂O_FourLithium manganate such as (0 <x <2) or lithium manganate having a spinel structure, MnO₂LiCoO₂LiNiO₂, Li_xV₂O_Five(0 <x <2) and the like, and examples of the disulfide compound include dithioglycol, 2,5-dimercapto-1,3,4-thiadiazole, S-triazine-2,4,6-trithiol, and the like. Examples of the conductive polymer include polyacetylene, polyphenylene, polyaniline, and polypyrrole.
[0120]
The N-oxide compound in the present invention functions as a positive electrode active material in the positive electrode, and is contained in the electrode as a reaction starting material, product, or intermediate product in the discharge reaction and charging reaction of the electrode reaction.
[0121]
Moreover, at the time of manufacturing the secondary battery of the present invention, the N-oxide compound may be used as it is, or may be manufactured using a compound that can be converted into an N-oxide structure by an electrode reaction. Examples of the compound that changes to the N-oxide compound by such an electrode reaction include a lithium salt of an anion body obtained by reducing the N-oxide compound, or a cation body and an electrolyte anion obtained by oxidizing the N-oxide compound. The salt which consists of, etc. are mentioned.
[0122]
Moreover, in this invention, in order to perform an electrode reaction more smoothly, you may mix the catalyst which accelerates | stimulates a redox reaction with an electrode material. Examples of such catalysts include conductive polymers such as polyaniline, polypyrrole, polythiophene, polyacetylene, and polyacene, basic compounds such as pyridine derivatives, pyrrolidone derivatives, benzimidazole derivatives, benzothiazole derivatives, and acridine derivatives, and metal ion complexes. Is mentioned.
[0123]
[Configuration of negative electrode]
The negative electrode in the present invention includes a first layer containing carbon as a main component, a second layer made of a material capable of inserting and extracting a lithium component, and a third layer containing at least one of lithium and a lithium-containing compound. And a multilayer structure in which a second layer is disposed between the first layer and the third layer. Each of the first, second and third layers may be a single layer or a plurality of layers. Regarding the positional relationship between the first, second, and third layers, the first layer and the third layer should not be in direct contact with each other, and the second layer is interposed therebetween. When there are a plurality of first, second, and third layers, any laminated structure can be used as long as the first layer and the third layer are not in direct contact. That is, any form shown below may be sufficient.
(A) A configuration in which the first layer is disposed on the outermost surface of the electrode.
(B) A configuration in which the second layer is disposed on the outermost surface of the electrode.
(C) A configuration in which the third layer is disposed on the outermost surface of the electrode.
[0124]
In addition, a multilayer film composed of the second layer and the third layer is arranged so that the first layer is sandwiched between the first layer and the lower part of the first layer, or the first layer and the second layer. It is also possible to adopt a configuration in which a multilayer film composed of these layers is arranged so that the third layer is sandwiched between the second layer above and below the third layer. In this way, high charge / discharge efficiency and good cycle characteristics are maintained by placing the first layer between the second layers or placing the third layer between the second layers. However, the battery capacity can be further improved.
[0125]
In the present invention, the second layer is preferably made of a material capable of inserting and extracting a lithium component. The form for occluding the lithium component includes not only the form for forming an alloy or the like, but also the form for incorporating lithium into the structure without forming an alloy with the material.
[0126]
In the negative electrode of the present invention, the second layer preferably has an amorphous structure. Electrochemical Li doping / undoping into the amorphous structure occurs at a lower potential than the crystal structure, so that the battery capacity can be increased while maintaining a high operating voltage and high charge / discharge efficiency. Here, the term “amorphous” in the present invention means a material having a broad scattering band having a vertex at 15 to 40 degrees in the 2θ value of the X-ray diffraction method using CuKα rays.
[0127]
The amorphous structure is structurally isotropic compared to the crystalline body, so that it has excellent strength against external stress and is chemically stable. For this reason, it is hard to react with electrolyte solution, it is excellent in the stability at the time of repeating the cycle of charging / discharging, and capacity | capacitance deterioration does not generate | occur | produce easily.
[0128]
The second layer is preferably a layer formed by vapor deposition, CVD, or sputtering. When these film forming methods are used, an amorphous lithium ion conductive film can be obtained uniformly on the negative electrode. With this film, the electrolytic distribution between the positive electrode and the negative electrode can be made uniform. For this reason, local concentration of the electric field does not occur, and even if a cycle passes, damage such as separation of the active material from the current collector does not occur, and stable battery characteristics can be obtained.
[0129]
  The lithium ion conductive material constituting the second layer in the present invention is not particularly limited as long as it is a material capable of transmitting a lithium component, but is selected from the group consisting of Si, Ge, Ag, Sn, In, and Pb. And those containing one or more elements, such as Si, Ge, Ag, Sn, In, Pb, oxides or composite oxides thereof, and sulfides thereof orcompositeOne or more materials selected from the group consisting of sulfides are preferred. B₂O_Three, P₂O_Five, Al₂O_Three, W_hO_3h-1(H = 1, 2, 3, 4), Mo_iO_3i-1(I = 1, 2, 3, 4), TiO, TiO₂One or more materials selected from the group consisting of can also be used. These are materials capable of inserting and extracting lithium or lithium ions. By selecting such a material and having an amorphous structure, the battery capacity can be increased while maintaining a high operating voltage and high charge / discharge efficiency. In particular, if the second layer is made of one or more materials selected from the group consisting of Si, Ge, Sn, Pb and their oxides, the operating voltage, charge / discharge efficiency and battery capacity are reduced. These materials are preferable because they can be remarkably improved and can be easily manufactured. Of these, Si, Sn, and oxides thereof are particularly preferable in that they have a small structural change when occluded lithium, are not easily deteriorated even after repeated charge and discharge, and provide good cycle characteristics.
[0130]
In the present invention, the substance constituting the third layer is not particularly limited as long as it is Li or a Li-containing compound, but preferably metal lithium, lithium alloy, lithium nitride or Li_3-xM_xA lithium nitride such as N (M = Co, Ni, Cu), or a mixture containing one or more of these. Since such a material can release a large amount of lithium electrochemically, the energy density of the battery can be improved.
[0131]
In the present invention, the substance constituting the third layer preferably has an amorphous structure. Since the amorphous structure is structurally isotropic compared to the crystal, it is chemically stable and hardly causes a side reaction with the electrolytic solution. For this reason, Li contained in the third layer is effectively used for improving the battery energy density.
[0132]
In the present invention, the substance constituting the third layer is preferably a layer formed by a vapor deposition method, a CVD method or a sputtering method. When these film forming methods are used, a uniform amorphous layer can be formed on the entire negative electrode. Further, since it is not necessary to use a solvent, a side reaction is unlikely to occur and a layer with higher purity can be produced, and Li contained in the third layer is effectively used to improve battery energy density.
[0133]
1, FIG. 2, FIG. 4, and FIG. 5 show structural examples (cross-sectional structures) of the negative electrode in the secondary battery of the present invention.
[0134]
The current collector 1 is an electrode member for taking out a current to the outside of the battery or taking in a current from the outside into the battery during charging and discharging. The current collector 1 may be a conductive metal foil. For example, Al, Cu, stainless steel, Au, W, Mo, or the like can be used.
[0135]
The carbon negative electrode 2 corresponds to the first layer, and is a negative electrode member that occludes or releases Li during charging and discharging. The carbon negative electrode 2 is a carbon capable of occluding Li, for example, natural graphite, petroleum coke, coal coke, pitch coke, carbon black, resin-fired carbon, organic polymer fired body, pyrolytic vapor-grown carbon fiber, meso Examples thereof include carbon materials such as carbon microbeads, mesophase pitch-based carbon fibers, polyacrylonitrile-based carbon fibers, low-temperature calcined carbon, fullerene, carbon nanotubes, and mixtures thereof.
[0136]
The second negative electrode layer 3 corresponds to the second layer and is a negative electrode member having lithium ion conductivity. B as such a material₂O_Three, P₂O_Five, Al₂O_Three, W_hO_3h-1(H = 1, 2, 3, 4), Mo_iO_3i-1(I = 1, 2, 3, 4), TiO, TiO₂And Si, Ge, Ag, Sn, In, Pb, oxides or composite oxides thereof, and sulfides or composite sulfides thereof, and these can be used alone or in combination of one or more. In order to improve lithium ion conductivity, lithium halide, lithium chalcogenide, or the like may be added to this material. This material is preferably amorphous. By using an amorphous material, the potential at which lithium is doped / undoped can be made lower than that of the crystal, and as a result, the operating voltage of the battery can be increased. The second negative electrode layer 3 is preferably formed by a CVD method, a vapor deposition method, or a sputtering method. If produced by these methods, the amorphous layer can be formed with uniform film quality and film thickness.
[0137]
The third negative electrode layer 4 corresponds to the third layer and is a negative electrode member made of lithium or a lithium-containing compound. Such materials include metallic lithium, lithium alloys, lithium nitride (lithium nitride (Li_ThreeN) or Li_3-xM_xN (M = Co, Ni, Cu) and the like) and mixtures thereof. These may be used alone or in combination of one or more. This material is preferably amorphous. By using an amorphous material, side reactions with the electrolytic solution can be suppressed, and lithium contained in the material can be efficiently used to compensate for the irreversible capacity. As a result, the initial charge / discharge efficiency of the battery can be improved and the energy density can be increased. The third negative electrode layer 4 is preferably formed by a CVD method, a vapor deposition method, or a sputtering method. If produced by these methods, the amorphous layer can be formed with uniform film quality and film thickness.
[0138]
The laminated structure of the negative electrode is a structure in which a carbon negative electrode layer 2 (first negative electrode layer), a second negative electrode layer 3, and a third negative electrode layer 4 are laminated in this order on the current collector 1, as shown in FIG. As shown in FIG. 2, a structure in which a carbon negative electrode layer 2, a second negative electrode layer 3, and a third negative electrode layer 4 are laminated in this order on both surfaces of the current collector 1, and the lamination shown in FIG. 1 as shown in FIG. A structure in which a second negative electrode layer 3 and a carbon negative electrode layer 2 are further laminated on a third negative electrode layer 4 having a structure, and a third negative electrode layer 4 and a second negative electrode layer 3 are formed on a current collector 1 as shown in FIG. Alternatively, a structure in which the carbon negative electrode layer 2, the second negative electrode layer 3, and the third negative electrode layer 4 are stacked in this order can be employed.
[0139]
[Conductive auxiliary material and ion conductive auxiliary material]
In this invention, when forming an electrode, you may mix a conductive support material and an ion conductive support material in order to reduce an impedance. Conductive auxiliary materials include graphite, carbon black, acetylene black, carbonaceous fine particles such as vapor-grown carbon fibers, metal fine particles such as copper, silver, gold, and platinum, and conductive properties such as polyaniline, polypyrrole, polythiophene, polyacetylene, and polyacene. Examples include polymers. Examples of the ion conduction auxiliary material include gel electrolytes and solid electrolytes.
[0140]
[Binder]
In the present invention, a binder may be mixed with the electrode material in order to strengthen the connection between the constituent materials of the electrode. Examples of such a binder include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, styrene-butadiene copolymer rubber, polytetrafluoroethylene, polypropylene, polyethylene. And resin binders such as polyimide.
[0141]
[Current collector and separator]
As the current collector in the present invention, a metal foil such as nickel, aluminum, copper, gold, silver, aluminum alloy, stainless steel, a metal flat plate, a mesh electrode, a carbon electrode, or the like can be used. Further, such a current collector may have a catalytic effect, or the active material and the current collector may be chemically bonded.
[0142]
In addition, for the purpose of preventing electrical contact between the negative electrode current collector and the positive electrode current collector, an insulating packing made of a plastic resin or the like may be disposed between them.
[0143]
Moreover, as a separator which can be used in the lithium secondary battery of the present invention, a polyolefin film such as polypropylene or polyethylene, or a porous film such as a fluororesin can be used.
[0144]
[Electrolyte and electrolyte]
Examples of the electrolytic solution in the present invention include propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), cyclic carbonates such as vinylene carbonate (VC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl Chain carbonates such as methyl carbonate (EMC) and dipropyl carbonate (DPC), aliphatic carboxylic acid esters such as methyl formate, methyl acetate and ethyl propionate, γ-lactones such as γ-butyrolactone, 1,2 -Cyclic ethers such as diethoxyethane and 1-ethoxy-1-methoxyethane, cyclic ethers such as tetrahydrofuran and 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolane, formamide, acetamide, dimethylformamide, dioxo , Acetonitrile, propylnitrile, nitromethane, ethyl monoglyme, phosphoric acid triester, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, 3-methyl-2-oxazolidinone, One or more aprotic organic solvents such as propylene carbonate derivative, tetrahydrofuran derivative, ethyl ether, 1,3-propane sultone, anisole, N-methylpyrrolidone, etc. are mixed and used. What melt | dissolved lithium salt can be used.
[0145]
As a lithium salt, for example, LiPF₆, LiAsF₆LiAlCl_FourLiClO_Four, LiBF_Four, LiSbF₆, LiCF_ThreeSO_Three, LiCF_ThreeCO₂, Li (CF_ThreeSO₂)₂, LiN (CF_ThreeSO₂)₂, LiB_TenCl_Ten, Lower aliphatic lithium carboxylates, lithium chloroborane, lithium tetraphenylborate, LiBr, LiI, LiSCN, LiCl, imides, and the like.
[0146]
Further, a polymer electrolyte may be used instead of the electrolytic solution. Polymeric substances used in these solid electrolytes include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-ethylene copolymer, vinylidene fluoride-monofluoroethylene copolymer, and vinylidene fluoride. -Vinylidene fluoride polymers such as trifluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, and acrylonitrile-methyl methacrylate copolymer Polymer, acrylonitrile-methyl acrylate copolymer, acrylonitrile-ethyl methacrylate copolymer, acrylonitrile-ethyl acrylate copolymer, acrylonitrile-methacrylic acid copolymer, acrylonitrile-acrylic Acid copolymer, an acrylonitrile - acrylonitrile polymers such as vinyl acetate copolymer, further polyethylene oxide, ethylene oxide - propylene oxide copolymers, and polymers of these acrylates body or methacrylate body thereof. These polymer substances can be used in the form of a gel containing an electrolytic solution, or only the polymer substance may be used as it is.
[0147]
[Method for producing positive electrode]
In this invention, it does not specifically limit about the manufacturing method of a positive electrode, A conventionally well-known method is employable. For example, a method of applying a solvent to the constituent material of the positive electrode to form a slurry and applying it to the electrode current collector, a method of adding a binder resin to the constituent material of the positive electrode and solidifying it by applying pressure, and baking the constituent material of the positive electrode with heat The method of hardening is mentioned.
[0148]
[Lamination of electrodes]
In the present invention, the laminated form of the positive electrode and the negative electrode is not particularly limited, and any laminated form can be adopted, and a multilayer laminated body, a form obtained by combining those laminated on both sides of the current collector, It can be set as the form which wound these.
[0149]
[Battery shape]
The shape and appearance of the battery of the present invention are not particularly limited, and conventionally known ones can be employed. That is, as such a battery shape, for example, an electrode laminate or a wound body is sealed with a metal case, a resin case, or a laminate film composed of a metal foil such as an aluminum foil and a synthetic resin film, or the like. Can be mentioned. Examples of the external appearance of the battery include a cylindrical shape, a square shape, a coin shape, and a sheet shape.
[0150]
【Example】
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
[0151]
(Example 1, Comparative Examples 1 and 2)
The positive electrode of the nonaqueous electrolyte secondary battery was produced by the following procedure. 25 mg of a quinonediimine-N, N′-dioxide compound represented by the chemical formula (7), 200 mg of graphite powder and 25 mg of a polytetrafluoroethylene resin binder were measured and mixed in an agate mortar. The mixture obtained by dry-mixing for about 10 minutes was roller-stretched under pressure to obtain a thin electrode plate having a thickness of 215 μm. The thin electrode plate was dried overnight at 80 ° C. in a vacuum, and then punched into a circle having a diameter of 12 mm to obtain a positive electrode molded body.
[0152]
The negative electrode of the non-aqueous electrolyte secondary battery shown in FIG. 1 was produced by the following procedure. First, a copper foil having a thickness of 10 μm was used as the current collector 1, and a carbon negative electrode layer (first negative electrode layer) 2 was deposited on the copper foil. This carbon negative electrode layer 2 is prepared by mixing polyvinylidene fluoride dissolved in N-methyl-2-pyrrolidone as a binder and a conductivity-imparting material into a graphite powder to form a paste. And dried to form. After drying, the carbon negative electrode layer 2 was compressed using a press.
[0153]
A second negative electrode layer 3 made of boron oxide was deposited on the carbon negative electrode layer 2 using a vacuum vapor deposition method, and a third negative electrode layer 4 made of lithium was further deposited using a vacuum vapor deposition method to obtain a negative electrode. .
[0154]
Next, the obtained positive electrode molded body was immersed in an electrolytic solution, and the electrolytic solution was infiltrated into the voids in the electrode molded body.
[0155]
As this electrolytic solution, 1 mol / l LiPF₆An ethylene carbonate / diethyl carbonate mixed solution (mixing ratio 3: 7 (volume ratio)) containing an electrolyte salt was used.
[0156]
As shown in FIG. 6, a positive electrode molded body impregnated with an electrolyte as a positive electrode 15 was placed on a positive-side coin-type battery case 16 that also served as a positive electrode current collector, and the electrolyte was similarly impregnated thereon. A porous film separator 14 was laminated. Furthermore, the negative electrode 13 was laminated | stacked on it and the frame-shaped insulating packing 12 was installed. Thereafter, a negative-side coin-type battery case 11 (also serving as a negative electrode current collector) was superposed. Pressure was applied to the obtained laminate by a caulking machine to obtain a sealed coin-type battery.
[0157]
As Comparative Example 1, a coin was formed in the same manner as in Example 1 except that a negative electrode composed of a current collector 1 made of a copper foil having a thickness of 10 μm shown in FIG. 3 and a carbon negative electrode layer 2 mainly composed of graphite was used. A type battery was produced. The total mass of the constituent material of the carbon negative electrode layer 2 included in this battery was the same as the total mass of the constituent material of the first negative electrode layer 2 included in the battery of Example 1.
[0158]
As Comparative Example 2, a coin-type battery was produced in the same manner as in Example 1 except that a negative electrode made of lithium foil was used (in that case, the negative-side coin-type battery case also serves as the negative electrode current collector).
[0159]
A charge / discharge cycle test was conducted on the battery using the negative electrode of Example 1 (the structure shown in FIG. 1) and the batteries of Comparative Examples 1 and 2. The voltage range of the charge / discharge test was 2.5 to 4.0V. Table 1 shows the results of the initial charge / discharge of Example 1 and Comparative Examples 1 and 2. The charge / discharge efficiencies of Comparative Examples 1 and 2 are 85.7% and 81.8%, respectively, whereas the charge / discharge efficiencies of Example 1 are 96.0%. It can be seen that the charge / discharge efficiency is high. In addition, the average discharge voltage of Example 1 and Comparative Examples 1 and 2 was 3.3V, 3.2V, and 3.4V, respectively.
[0160]
Table 1 shows the evaluation results of the charge / discharge cycle characteristics. The discharge capacity ratio in Table 1 represents the ratio of the discharge capacity (C300) of 300 cycles with respect to the discharge capacity (C1) of 1 cycle as 100%. In Example 1, 90% or more of the initial capacity is maintained even after 300 cycles, and it can be seen that it has cycle characteristics equivalent to those of Comparative Example 1. The discharge capacity after 300 cycles of Comparative Example 2 was 22.7% of the initial discharge capacity.
[0161]
From the evaluation results of this example and the comparative example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention has high capacity and charge / discharge efficiency and stable cycle characteristics.
[0162]
[Table 1]

[0163]
(Examples 2 and 3)
In the present embodiment, a current collector 1 made of a copper foil having a thickness of 10 μm, a carbon negative electrode layer (first negative electrode layer) 2 containing hard carbon as a main component, a second negative electrode layer 3 made of silicon, and metallic lithium The third negative electrode layer 4 was laminated in this order to produce the negative electrode shown in FIG. The second negative electrode layer 3 was formed by the CVD method in Example 2 and by the sputtering method in Example 3. Formation of the 3rd negative electrode layer 4 used the vacuum evaporation method in any Example.
[0164]
A coin-type battery was produced in the same manner as in Example 1 except that these negative electrodes were used.
[0165]
A charge / discharge cycle test was performed on the batteries using the negative electrodes (structures in FIG. 1) of Examples 2 and 3 respectively. The voltage range of the charge / discharge test was 2.5 to 4.0V. Table 2 shows the results of the first charge and discharge in Examples 2 and 3. The charge / discharge efficiencies of Examples 2 and 3 are 90% or more, and it can be seen from these results that the initial charge / discharge efficiencies of Examples 2 and 3 are sufficiently high. The average discharge voltage in Examples 2 and 3 was 3.3V.
[0166]
From this result, even if it uses the material which has a hard carbon as a main component for the 1st negative electrode layer 2, it can improve charging / discharging efficiency by setting it as the structure of this invention which formed the 2nd negative electrode layer 3 and the 3rd negative electrode layer 4. Became clear.
[0167]
Table 2 shows the results of the charge / discharge cycle characteristics. It can be seen that Examples 2 and 3 retain 90% or more of the initial capacity even after 300 cycles.
[0168]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0169]
[Table 2]

[0170]
(Examples 4 to 6)
In this example, a current collector 1 made of a copper foil having a thickness of 10 μm, a carbon negative electrode layer (first negative electrode layer) 2 containing hard carbon as a main component, SiO 2_x(0 <x ≦ 2) (Example 4) or SnO_x(0 <x ≦ 2) (Example 5) or a second negative electrode layer 3 made of a mixture of Si and Sn (Example 6) and a third negative electrode layer 4 made of a lithium aluminum alloy are laminated in this order. The negative electrode shown in 1 was produced.
[0171]
The total mass of the constituent material of the carbon negative electrode layer 2 using as a main component the hard carbon contained in each of the batteries of Examples 4 to 6 is based on the hard carbon contained in each of the batteries of Examples 2 and 3. The total mass of the constituent materials of the negative electrode layer 2 used was the same.
[0172]
The formation of the second negative electrode layer 3 is the same as that in Example 4._xFilm, SnO of Example 5_xThe film was formed by vapor deposition. Formation of a film (SiSn film) made of a mixture of Si and Sn in Example 6 was performed by depositing Si and Sn in separate crucibles and depositing them using a laser. In that case, the ratio of Si and Sn was controlled by measuring each vapor deposition amount using a quartz oscillator.
[0173]
The ratio of lithium and aluminum in the lithium aluminum alloy of the third negative electrode layer 4 was 98% and 2%, respectively. The lithium aluminum alloy film was formed by using a method in which lithium and aluminum were put in separate crucibles and deposited using a laser. At that time, the ratio of lithium to aluminum was controlled by measuring the amount of each vapor deposition using a crystal resonator.
[0174]
Coin batteries were produced in the same manner as in Example 1 except that these negative electrodes were used.
[0175]
A charge / discharge cycle test was performed on the batteries using the negative electrodes (structures in FIG. 1) of Examples 4 to 6 respectively. The voltage range of the charge / discharge test was 2.5 to 4.0V. Table 3 shows the results of the first charge and discharge of Examples 4 to 6. The charge / discharge efficiencies of Examples 4 to 6 are all as high as 90% or more, and it can be seen that even when a lithium aluminum alloy is used as the third negative electrode layer 4, the charge / discharge efficiencies are improved. In addition, the average discharge voltage of Example 4, 5 and 6 was 3.2V, 3.2V, and 3.3V, respectively.
[0176]
Table 3 shows the results of the charge / discharge cycle characteristics. It can be seen that Examples 4 to 6 retain 90% or more of the initial capacity even after 300 cycles.
[0177]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0178]
[Table 3]

[0179]
(Example 7)
In this example, a current collector 1 made of a copper foil having a thickness of 10 μm, a carbon negative electrode layer (first negative electrode layer) 2 containing graphite as a main component, SiO 2_xA second negative electrode layer 3 made of (0 <x ≦ 2) and a third negative electrode layer 4 made of a mixture film of metallic lithium and lithium nitride were laminated in this order to produce the negative electrode shown in FIG. SiO of second negative electrode layer 3_xThe film was formed using a vacuum deposition method. The ratio of metallic lithium and lithium nitride in the mixture of the third negative electrode layer 4 was 90% and 10%, respectively. The mixture film was formed using a method in which metallic lithium and lithium nitride were put in separate harnesses and vapor-deposited using a laser.
[0180]
A coin-type battery was produced in the same manner as in Example 1 except that this negative electrode was used.
[0181]
A charge / discharge cycle test was conducted on the battery using the negative electrode of the present example (structure shown in FIG. 1). The voltage range of the charge / discharge test was 2.5 to 4.0V. Table 4 shows the results of the initial charge / discharge of this example. The charge / discharge efficiency of this example was sufficiently high at 94% or more, and it was revealed that the charge / discharge efficiency was improved even when a mixture of metallic lithium and lithium nitride was used as the third negative electrode layer 4. In addition, the average discharge voltage of this example was 3.3V.
[0182]
Table 4 shows the results of the charge / discharge cycle characteristics. In the present embodiment, it can be seen that 90% or more of the initial capacity is maintained even after 300 cycles.
[0183]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0184]
[Table 4]

[0185]
(Examples 8 and 9)
The structures of the negative electrodes of Examples 8 and 9 are shown in FIGS. 4 and 5, respectively. In Example 8, the third negative electrode layer 4 is sandwiched between the second negative electrode layers 3 from above and below. In Example 9, the first negative electrode layer 2 is sandwiched between the second negative electrode layers 3 from above and below.
[0186]
In this embodiment, a copper foil having a thickness of 10 μm is used as the current collector 1, a material mainly composed of graphite is used as the first negative electrode layer 2, silicon is used for the second negative electrode layer 3, and the third negative electrode layer 4 is used. Metal lithium was used for. A vacuum deposition method was used to form the second negative electrode layer 3 and the third negative electrode layer 4. The total mass of the constituent material of the first negative electrode layer 2 included in each of the batteries of Examples 8 and 9 was the same as the total mass of the constituent material of the carbon negative electrode layer 2 included in the battery of Example 1.
[0187]
Coin batteries were produced in the same manner as in Example 1 except that these negative electrodes were used.
[0188]
The batteries using the negative electrodes of Examples 8 and 9 were each subjected to a charge / discharge cycle test. The voltage range of the charge / discharge test was 2.5 to 4.0V. The results of the first charge / discharge of Examples 8 and 9 are shown in Table 5 together with the results of Comparative Examples 1 and 2. The charge / discharge efficiencies of Examples 8 and 9 are both 90% or higher, which is higher than the charge / discharge efficiencies of Comparative Examples 1 and 2, indicating that the charge / discharge efficiencies are improved. The average discharge voltage in Examples 8 and 9 was 3.3V.
[0189]
Table 5 shows the results of the charge / discharge cycle characteristics. In Examples 8 and 9, 90% or more of the initial capacity is maintained after 300 cycles, which is superior to Comparative Example 2 and has a cycle characteristic equivalent to or higher than that of Comparative Example 1.
[0190]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0191]
[Table 5]

[0192]
(Comparative Example 3)
In this comparative example, LiCoO was used in place of the quinonediimine-N, N′-dioxide compound represented by the chemical formula (7) used in Example 1.₂A positive electrode was produced in the same manner as in Example 1 except that 25 mg was used, and a coin-type battery was produced in the same manner as in Example 1 except that this positive electrode was used.
[0193]
This battery was subjected to a charge / discharge cycle test. The voltage range of the charge / discharge test was 2.5 to 4.0V. The results of the initial charge / discharge of this comparative example are shown in Table 6 together with the results of Example 1. The charge / discharge efficiency of Example 1 is 96.0%, whereas the charge / discharge efficiency of this comparative example is as low as 64.6%. From this result, quinonediimine represented by the chemical formula (7) as a positive electrode material It can be seen that the initial charge and discharge efficiency is improved by using the N, N′-dioxide compound. In addition, the average discharge voltage of Comparative Example 3 was 3.7V.
[0194]
Table 6 shows the evaluation results of the charge / discharge cycle characteristics. The discharge capacity after 300 cycles of this comparative example was 87.9% of the initial discharge capacity.
[0195]
[Table 6]

[0196]
(Examples 10 and 11)
In this example, instead of the quinonediimine-N, N′-dioxide compound represented by the chemical formula (7) used in Example 1, the quinonediimine-N, N′— represented by the chemical formula (8) in Example 10 was used. A positive electrode was prepared in the same manner as in Example 1 except that 25 mg of the dioxide compound and 25 mg of the quinonediimine-N, N′-dioxide compound represented by the chemical formula (10) in Example 11 were used. Respectively produced coin-type batteries in the same manner as in Example 1.
[0197]
A charge / discharge cycle test was conducted on these batteries. The voltage range of the charge / discharge test was 2.5 to 4.0V. Table 7 shows the results of the initial charge / discharge and the evaluation results of the charge / discharge cycle characteristics of this example. The charge / discharge efficiency of these examples is 90% or more. From this result, a positive electrode using a quinonediimine-N, N′-dioxide compound as a positive electrode material, a first layer mainly composed of carbon, It can be seen that a battery using a multilayered negative electrode including a second layer mainly composed of a film material having lithium ion conductivity and a third layer made of Li has high initial charge / discharge efficiency. In addition, the average discharge voltages of these examples were 3.1V and 3.0V, respectively.
[0198]
Moreover, the discharge capacity after 300 cycles of Examples 10 and 11 was 91.4% and 90.3% of the initial discharge capacity, respectively.
[0199]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0200]
[Table 7]

[0201]
(Examples 12 to 16)
The positive electrode of the nonaqueous electrolyte secondary battery of Example 12 was produced by the following procedure. 40 mg of quinonediimine-N, N′-dioxide polymer compound represented by the chemical formula (12), 15 mg of acetylene black powder, 36 mg of artificial graphite powder, 10 mg of 40% by mass solution of styrene-butadiene latex, 212 mg of 2% by mass solution of methylcellulose, 1 ml of water was mixed and the mixture was homogenized using a homogenizer to obtain a slurry. 15 mg of this slurry was applied to the surface of the aluminum foil by a doctor blade method to form a thin film. This was punched into a circle having a diameter of 12 mm to obtain a positive electrode molded body.
[0202]
In Example 12, a coin-type battery was produced in the same manner as in Example 1 except that this positive electrode molded body was used as a positive electrode.
[0203]
In Examples 13 to 16, 40 mg of the following quinonediimine-N, N′-dioxide polymer compound was used instead of the quinonediimine-N, N′-dioxide compound represented by the chemical formula (12) used in Example 12. Otherwise, a positive electrode was produced in the same manner as in Example 12, and a coin-type battery was produced in the same manner as in Example 12 except that this positive electrode was used.
[0204]
Example 13: Compound represented by chemical formula (11),
Example 14: Compound represented by chemical formula (15),
Example 15: Compound represented by chemical formula (17),
Example 16: Compound represented by the chemical formula (18)
[0205]
The batteries of Examples 12 to 16 were subjected to charge / discharge cycle tests. The voltage range of the charge / discharge test was 2.5 to 4.0V. Table 8 shows the results of the initial charge / discharge and the evaluation results of the charge / discharge cycle characteristics of Examples 12 to 16. The charge / discharge efficiencies of Examples 12 to 16 are 90% or more or a value close to 90%. From these results, the positive electrode using quinonediimine-N, N′-dioxide polymer compound as the positive electrode material and carbon as the main component A battery using a negative electrode having a multilayer structure including a first layer, a second layer mainly composed of a film-like material having lithium ion conductivity, and a third layer made of Li is first charged. It can be seen that the discharge efficiency is high. In addition, although the average discharge voltage of Examples 12-16 fell gradually in Example 13, it was 3.1V, 3.1V, 3.1V, and 3.2V in the other Examples, respectively. .
[0206]
The discharge capacities after 300 cycles of Examples 12 to 16 were 90.4%, 89.7%, 92.8%, 94.8%, and 93.4% of the initial discharge capacity, respectively.
[0207]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0208]
[Table 8]

[0209]
(Examples 17 to 19)
In this example, 25 mg of the following polyacene-type diazine-N, N′-dioxide compound was used in place of the quinonediimine-N, N′-dioxide compound represented by the chemical formula (7) used in Example 1. Produced a positive electrode in the same manner as in Example 1, and produced coin-type batteries in the same manner as in Example 1 except that this positive electrode was used.
[0210]
Example 17: Compound represented by chemical formula (24),
Example 18: Compound represented by chemical formula (23),
Example 19: Compound represented by the chemical formula (27)
[0211]
The batteries of Examples 17 to 19 were subjected to charge / discharge cycle tests. The voltage range of the charge / discharge test was 2.5 to 4.5V. Table 9 shows the results of the initial charge / discharge and the evaluation results of the charge / discharge cycle characteristics of Examples 17 to 19. The charge / discharge efficiencies of Examples 17 to 19 are all 90% or higher. From this result, the positive electrode using a polyacene type diazine-N, N′-dioxide compound as the positive electrode material, and carbon A battery using a negative electrode having a multilayer structure including one layer, a second layer mainly composed of a film-like material having lithium ion conductivity, and a third layer made of Li has an initial charge / discharge efficiency. I understand that it is expensive. In addition, the average discharge voltage of Examples 17-19 was 3.9V, 3.8V, 3.7V, respectively.
[0212]
Moreover, the discharge capacity after 300 cycles of Examples 17 to 19 was 92.5%, 90.6%, and 91.4% of the initial discharge capacity, respectively.
[0213]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0214]
[Table 9]

[0215]
(Examples 20 to 24)
In this example, a positive electrode was prepared in the same manner as in Example 1 except that 25 mg of the following compound was used instead of the quinonediimine-N, N′-dioxide compound represented by the chemical formula (7) used in Example 1. A coin type battery was prepared in the same manner as in Example 1 except that this positive electrode was used.
[0216]
Example 20: Linear diazine-N, N′-dioxide polymer compound represented by chemical formula (31),
Example 21: Side-chain diazine-N, N′-dioxide polymer compound represented by chemical formula (38),
Example 22: Side chain diazine-N, N′-dioxide polymer compound represented by the chemical formula (39),
Example 23: Side chain diazine-N, N′-dioxide polymer compound represented by the chemical formula (41),
Example 24: Side chain type diazine-N, N′-dioxide polymer compound represented by the chemical formula (43)
[0217]
The batteries of Examples 20 to 24 were subjected to a charge / discharge cycle test. The voltage range of the charge / discharge test was 2.5 to 4.5V. Table 10 shows the results of the initial charge / discharge and the evaluation results of the charge / discharge cycle characteristics of Examples 20 to 24. The charge / discharge efficiencies of Examples 20 to 24 are all 90% or more, and from this result, the positive electrode using the linear and side chain diazine-N, N′-dioxide polymer compounds as the positive electrode material, carbon A battery using a multilayer structure including a first layer mainly composed of lithium, a second layer mainly composed of a film-like material having lithium ion conductivity, and a third layer composed of Li It can be seen that the initial charge / discharge efficiency is high. In addition, the average discharge voltage of Examples 20-24 was 3.9V, 3.8V, 3.9V, 3.8V, 3.7V.
[0218]
Moreover, the discharge capacity after 300 cycles of Examples 20 to 24 was 94.1%, 95.3%, 93.5%, 91.1%, and 95.2% of the initial discharge capacity, respectively.
[0219]
From the evaluation results in this example, it was proved that the secondary battery including the positive electrode and the negative electrode according to the present invention had high capacity and charge / discharge efficiency and stable cycle characteristics.
[0220]
[Table 10]

[0221]
【The invention's effect】
As described above, according to the present invention, the positive electrode active material contains an N-oxide compound, and the negative electrode structure includes a first layer mainly composed of carbon and a film-like material having lithium ion conductivity. By adopting a multilayer structure including the second layer containing the main component and the third layer containing the Li or Li-containing compound as the main component, the capacity density is high (that is, the energy density is high), and the charge / discharge efficiency is high. And a secondary battery excellent in cycle characteristics can be obtained.
[0222]
In the present invention, the N-oxide compound used for the positive electrode active material can realize a high capacity density because the oxidation-reduction reaction sites are localized.
[0223]
Further, according to the configuration of the present invention, Li contained in the third layer of the negative electrode can efficiently compensate for the irreversible capacity of the negative electrode, and both high charge / discharge efficiency and discharge capacity can be achieved. Moreover, a part of Li contained in the third layer is doped into the second layer, and the lithium ion conductivity of the second layer is increased. Since such a film-like material having high lithium ion conductivity exists uniformly in the negative electrode, the electric field distribution between the positive electrode and the negative electrode becomes uniform. As a result, local concentration of the electric field can be prevented and good cycle characteristics can be realized.
[Brief description of the drawings]
FIG. 1 is an example of a cross-sectional structure of a negative electrode in a secondary battery of the present invention.
FIG. 2 is an example of a cross-sectional structure of a negative electrode in the secondary battery of the present invention.
FIG. 3 is an example of a cross-sectional structure of a negative electrode in a secondary battery of a comparative example.
FIG. 4 is an example of a cross-sectional structure of a negative electrode in the secondary battery of the present invention.
FIG. 5 is an example of a cross-sectional structure of a negative electrode in the secondary battery of the present invention.
FIG. 6 is an example of a structure of a secondary battery of the present invention.
[Explanation of symbols]
1 Current collector
2 Carbon negative electrode layer (first negative electrode layer)
3 Second negative electrode layer
4 Third negative electrode layer
11 Negative electrode current collector
12 Insulation packing
13 Negative electrode
14 Separator
15 Positive electrode
16 Positive current collector

Claims (15)

In a secondary battery including at least a positive electrode, a negative electrode, and an electrolyte,
The positive electrode is represented by the following general formula (1) as a positive electrode active material.

Containing an N-oxide compound having a partial structure represented by
The negative electrode includes a first layer containing carbon as a main component, a second layer made of a lithium ion conductive material that is different from the first layer and capable of inserting and extracting a lithium component, and a metal lithium, lithium alloy, lithium nitride, and a third layer consisting of _{Li 3-x M x N (} M = Co, Ni, Cu) one or more selected from, the first layer and the third Having a multilayer structure in which a second layer is arranged between the layers,
Secondary battery in which the N- oxide compound, characterized in that it has a partial structure represented by the following general formula (2) in the molecule.

Wherein R _{1 to} R ₄ are each independently a hydrogen atom, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group. Substituted or unsubstituted cycloalkyl group, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or Unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted aryloxycarbonyl group, substituted or unsubstituted acyl group, or substituted or unsubstituted acyloxy group In addition, in these substituents, one or more atoms are sulfur atoms, silicon Child, phosphorus atom, or a boron atom may be substituted with, or may form a ring structure with substituents other.) In a secondary battery including at least a positive electrode, a negative electrode, and an electrolyte,
The positive electrode is represented by the following general formula (1) as a positive electrode active material.

Containing an N-oxide compound having a partial structure represented by
The negative electrode includes a first layer containing carbon as a main component, a second layer made of a lithium ion conductive material that is different from the first layer and capable of inserting and extracting a lithium component, and a metal lithium, lithium alloy, lithium nitride, and a third layer consisting of _{Li 3-x M x N (} M = Co, Ni, Cu) one or more selected from, the first layer and the third Having a multilayer structure in which a second layer is arranged between the layers,
Secondary battery in which the N- oxide compound, characterized in that it has a partial structure represented by the following general formula (3) in the molecule.

Wherein R _{1 to} R ₈ are each independently a hydrogen atom, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group. Substituted or unsubstituted cycloalkyl group, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or Unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted aryloxycarbonyl group, substituted or unsubstituted acyl group, or substituted or unsubstituted acyloxy group In addition, in these substituents, one or more atoms are sulfur atoms, silicon Child, phosphorus atom, or a boron atom may be substituted with, or may form a ring structure with substituents other.) In a secondary battery including at least a positive electrode, a negative electrode, and an electrolyte,
The positive electrode is represented by the following general formula (1) as a positive electrode active material.

Containing an N-oxide compound having a partial structure represented by
The negative electrode includes a first layer containing carbon as a main component, a second layer made of a lithium ion conductive material that is different from the first layer and capable of inserting and extracting a lithium component, and a metal lithium, lithium alloy, lithium nitride, and a third layer consisting of _{Li 3-x M x N (} M = Co, Ni, Cu) one or more selected from, the first layer and the third Having a multilayer structure in which a second layer is arranged between the layers,
Secondary battery in which the N- oxide compound, characterized in that it has a partial structure represented by the following general formula (4) in the molecule.

Wherein R _{1 to} R ₈ are each independently a hydrogen atom, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group. Substituted or unsubstituted cycloalkyl group, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or Unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted aryloxycarbonyl group, substituted or unsubstituted acyl group, or substituted or unsubstituted acyloxy group In addition, in these substituents, one or more atoms are sulfur atoms, silicon Child, phosphorus atom, or a boron atom may be substituted with, or may form a ring structure with substituents other.) The secondary battery according to any one of claims 1 to 3 wherein the N- oxide compound is an oligomer or a polymer compound. In a secondary battery including at least a positive electrode, a negative electrode, and an electrolyte,
The positive electrode is represented by the following general formula (1) as a positive electrode active material.

Containing an N-oxide compound having a partial structure represented by
The negative electrode includes a first layer containing carbon as a main component, a second layer made of a lithium ion conductive material that is different from the first layer and capable of inserting and extracting a lithium component, and a metal lithium, lithium alloy, lithium nitride, and a third layer consisting of _{Li 3-x M x N (} M = Co, Ni, Cu) one or more selected from, the first layer and the third Having a multilayer structure in which a second layer is arranged between the layers,
Rechargeable battery the N- oxide compound is characterized by having a structure represented by the following general formula (5).

(In the formula, n, m, n ′ and m ′ each independently represent an integer of 0 or more. The order of condensation of the diazine ring and the benzene ring may be alternating or random. , R ₁ , R ₂ , R ₃ , R ₄ , R ^a , R ^b , R ^c , and R ^d are each independently a hydrogen atom, halogen atom, hydroxyl group, nitro group, nitroso group, cyano group, carboxyl group Substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted cycloalkyl group, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group, substituted or Unsubstituted aralkyl group, substituted or unsubstituted amino group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkoxycarbonyl group, substituted Or an unsubstituted aryloxycarbonyl group, a substituted or unsubstituted acyl group, or a substituted or unsubstituted acyloxy group, provided that when n is 2 or more, R ^a and R ^b are the same or different. In the case where n ′ is 2 or more, R ^c and R ^d may be the same or different from each other, and one or more atoms of these substituents are sulfur atoms, silicon atoms And may be substituted with a phosphorus atom or a boron atom, and a substituent may form a ring structure.) The N-oxide compound has two substituents among the substituents R ₁ , R ₂ , R ₃ , R ₄ , R ^a , R ^b , R ^c , and R ^{d having} the structure represented by the general formula (5). 6. The secondary battery according to claim 5 , wherein the secondary battery is an oligomer or polymer compound having a divalent group having two bonds as a structural unit. The N-oxide compound is substituted with _one of the substituents R ₁ , R ₂ , R ₃ , R ₄ , R ^a , R ^b , R ^c , and R ^{d having} the structure represented by the general formula (5). 6. The secondary battery according to claim 5 , which is an oligomer or polymer compound having a structural unit having a monovalent group having one bond instead. The N- oxide compound, reaction starting materials in the electrode reaction, product, or secondary battery according to any one of claims 1 to 7 containing as an intermediate product. The secondary battery according to any one of claims 1 to 8 the second layer of the negative electrode has an amorphous structure. The second layer of the negative electrode, deposition, secondary battery according to any one of claims 1 to 9 which is a layer formed by a CVD method or a sputtering method. The second layer of the negative electrode comprises B ₂ O ₃ , P ₂ O ₅ , Al ₂ O ₃ , W _h O _3h-1 (h = 1, 2, 3, 4), Mo _i O _3i-1 (i = 1,2,3,4), TiO, rechargeable battery according to any one of claims 1 to 10 is intended to include one or more materials selected from the group consisting of TiO _2. The secondary battery according to any one of claims 1 to 11 , wherein the second layer of the negative electrode contains one or more elements selected from the group consisting of Si, Ge, Ag, Sn, In, and Pb. . One or more selected from the group consisting of the second layer of the negative electrode is Si, Ge, Ag, Sn, In, Pb, oxides or composite oxides thereof, and sulfides or composite sulfides thereof. the secondary battery according to any one of claims 1 to 12 is intended to include materials. The third layer of the negative electrode, a secondary battery according to any one of the vapor deposition method, according to claim 1 to 13 is a layer formed by a CVD method or a sputtering method. The secondary battery according to any one of claims 1 to 14 , wherein the third layer of the negative electrode includes one or more materials selected from the group consisting of metallic lithium, a lithium alloy, and lithium nitride.

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