JP4680338B2 - POLYMER ELECTROLYTE FUEL CELL AND METHOD OF CONNECTING THE SAME - Google Patents

Description

（式中、５≦ｘ≦１３．５、ｙ≒１０００、ｍ＝１、ｎ＝２である。）
【００１５】
で示されるパーフルオロカーボンスルホン酸の粉末をエチルアルコールに分散させた分散液を混合し、触媒ペーストを得た。
一方、電極の多孔性基材、すなわちガス拡散層を構成するカーボンペーパーを撥水処理した。厚み３６０μｍのカーボン不織布（東レ（株）製のＴＧＰ−Ｈ−１２０）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に含浸した後、これを乾燥し、４００℃で３０分間加熱することで、撥水性を与えた。
つぎに、炭素微粉末（電気化学工業（株）製のアセチレンブラックＨＳ−１００、一次粒子経：５３ｎｍ、比表面積：３７ｍ²／ｇ、ＤＢＰ吸油量：２００ｃｃ／１００ｇ）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に分散させ、炭素微粉末とポリテトラフルロエチレンの混合比（重量）を８７：１３としたペーストを得た。このペーストを上述のように撥水処理をしたカーボン不織布の両面に塗布し、乾燥した後、４００℃で３０分間加熱することで、炭素微粉末層を形成した。このとき、炭素微粉末層の一部は、カーボン不織布の中に埋まり込んでいた。このようにして作製したカーボン不織布と炭素微粉末層を合わせてガス拡散層１とした。
【００１６】
スクリーン印刷法を用いて、前記炭素微粉末層の上に前述の触媒ペーストを塗布して触媒層２を形成した。このようにして作製した触媒層２、炭素微粉末層およびカーボン不織布を合わせて電極とした。電極中に含まれる白金量は０．５ｍｇ／ｃｍ²、パーフルオロカーボンスルホン酸の量は１．２ｍｇ／ｃｍ²となるように調整した。この電極をアノード電極およびカソード電極の両方に使用した。
つぎに、外寸の大きさを前述の電極より５ｍｍ大きくした水素イオン伝導性高分子電解質膜（米国デュポン社製のナフィオン１１２）３の両面に、１対の電極を、触媒層２が電解質膜３に接するようにホットプレスで接合し、ＭＥＡを得た。このＭＥＡ２２を、その両面から気密性を有するカーボン製のセパレータ４で挟み込んで単電池の構成とした。セパレータ４の厚さは４ｍｍであった。
【００１７】
以上の単電池を２セル積層して、電池構成単位を得た。冷却部のシール用Ｏリングは用いなかった。
電池構成単位のセパレータとしては、図２に示すように、一方の面に冷却水流路２４を配置し、他方の面にはガス流路６を配置したセパレータ４ａ、一方の面にガス流路５を配置し他方の面にガス流路６を配置したセパレータ４ｂ、および一方の面にガス流路５を配置し他方の面に冷却水流路２４を配置したセパレータ４ｃから構成されるものを用いた。また、図３に示すように、ガスの供給口１１および１３と排気口１１’および１３’ならびに冷却水の供給口１２と排出口１２’は、互いに対向する辺に設けられている。なお、図３において線状部材などの詳細は省略した。
ガス流路５および６、ならびに冷却水流路２４は、切削加工によって、セパレータの表面に形成することができる。本実施例においては、図２に示すような形状で、幅２ｍｍ、深さ１ｍｍの溝をガス流路５としてセパレータの面に刻んで形成した。
【００１８】
このようにして電池構成単位を５０個積層した積層体の両端部に、金属製の集電板５２と電気絶縁材料からなる絶縁板５１、エンドプレート３１および３２を順に配した。さらに、この積層体の上下にエンドプレートを配し、図１〜３で説明した実施の形態の締結構造を設けた。すなわち、線径１ｍｍの金属線を線状部材３９として用い、エンドプレート３１および３２とを介して締結力を与える構造とした。線状部材３９には２３００ｋｇｆの張力を与え、組立時の締結圧力を１３ｋｇｆ／ｃｍ²とした。感圧紙によりセパレータ板の圧力分布を調べたところ、全面にわたって均一な圧力分布となっていることが確認された。
本実施の形態によると、従来のセパレータ外側にロッドを配置して締結力を与える方法に比べ、セパレータの内側から締結力を印加することができるため、エンドプレートの変形が激減する。そのためエンドプレートの厚みを５ｍｍ以下にすることも可能である。
【００１９】
《実施の形態２》
本実施の形態おける燃料電池を図８、２および３に示す。特に、採用した締め付け構造は図８に示す。
単電池の積層体３０の上下にはエンドプレート３１および３２が配されている。出力端子（図示せず。）を有する単電池の積層体３０とエンドプレート３１および３２とは、特に図示していないが、絶縁手段によって電気的に絶縁されているものとした。エンドプレート３１、電池積層体３０およびエンドプレート３２は、線状部材３９により締め付けられている。すなわち、積層体３０を囲繞する形に巻回した線状部材３９、前記線状部材３９の端部を固定した固定部材３３、エンドプレート３２の底面に設けた凹部３６と対応させて設けた凸部３７にバネ３８を装着した補助プレート３４、固定部材３３に設けたネジ穴に螺合させたネジ３５からなる締付け部材３５’により、積層体３０ならびにエンドプレート３１および３２が締め付けられている。なお、バネ３８は皿バネであってもよい。
線状部材３９を積層体３０およびエンドプレート３１および３２ならびに補助プレート３４を囲繞する形に巻回し、線状部材３９にしかるべき張力を与えた後、固定部材３３およびネジ３５により線状部材３９を固定する。線状部材３９にしかるべき張力を与えた後締結することで、エンドプレートを介して積層体３０が締め付けられ、シール部や電極に必要な面圧がかけられる。
なお、電極にガスを供給するためのガス供給口ならびに冷却水供給口に対応する排出口は供給口を有する側とは反対側の下面に設けられている。
【００２０】
つぎに、この実施の形態を具体化した例を以下に説明する。
まず、ＭＥＡの作製方法について説明する。炭素微粉末（米国キャボット社製のＶＸＣ７２、一次粒子経：３０ｎｍ、比表面積：２５４ｍ²／ｇ）に、平均粒径約３０Åの白金粒子を２５重量％担持したものを電極の触媒とした。この触媒粉末をイソプロパノールに分散させた分散液に、式（１）：

（式中、５≦ｘ≦１３．５、ｙ≒１０００、ｍ＝１、ｎ＝２である。）
【００２１】
で示されるパーフルオロカーボンスルホン酸の粉末をエチルアルコールに分散させた分散液を混合し、触媒ペーストを得た。
一方、電極の多孔性基材、すなわちガス拡散層を構成するカーボンペーパーを撥水処理した。厚み３６０μｍのカーボン不織布（東レ（株）製のＴＧＰ−Ｈ−１２０）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に含浸した後、これを乾燥し、４００℃で３０分間加熱することで、撥水性を与えた。
つぎに、炭素微粉末（電気化学工業（株）製のアセチレンブラックＨＳ−１００、一次粒子経：５３ｎｍ、比表面積：３７ｍ²／ｇ、ＤＢＰ吸油量：２００ｃｃ／１００ｇ）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に分散させ、炭素微粉末とポリテトラフルロエチレンの混合比（重量）を８７：１３としたペーストを得た。このペーストを上述のように撥水処理をしたカーボン不織布の両面に塗布し、乾燥した後、４００℃で３０分間加熱することで、炭素微粉末層を形成した。このとき、炭素微粉末層の一部は、カーボン不織布の中に埋まり込んでいた。このようにして作製したカーボン不織布と炭素微粉末層を合わせてガス拡散層１とした。
【００２２】
スクリーン印刷法を用いて、前記炭素微粉末層の上に前述の触媒ペーストを塗布して触媒層２を形成した。このようにして作製した触媒層２、炭素微粉末層およびカーボン不織布を合わせて電極とした。電極中に含まれる白金量は０．５ｍｇ／ｃｍ²、パーフルオロカーボンスルホン酸の量は１．２ｍｇ／ｃｍ²となるように調整した。この電極をアノード電極およびカソード電極の両方に使用した。
つぎに、外寸の大きさを前述の電極より５ｍｍ大きくした水素イオン伝導性高分子電解質膜（米国デュポン社製のナフィオン１１２）３の両面に、１対の電極を、触媒層２が電解質膜３に接するようにホットプレスで接合し、ＭＥＡを得た。
このＭＥＡ２２を、その両面から気密性を有するカーボン製のセパレータ４で挟み込んで単電池の構成とした。セパレータ４の厚さは、４ｍｍであった。
【００２３】
以上の単電池を２セル積層して、電池構成単位を得た。冷却部のシール用Ｏリングは用いなかった。
電池構成単位のセパレータは、図２に示すように、一方の面に冷却水流路２４を配置し、他方の面にはガス流路６を配置したセパレータ４ａ、一方の面にガス流路５を配置し、他方の面にガス流路６を配置したセパレータ４ｂ、および一方の面にガス流路５を配置し、他方の面に冷却水流路２４を配置したセパレータ４ｃから構成されるものを用いた。また、図３に示すように、ガス路の供給口１１および１３と排気口１１’および１３’ならびに冷却水の供給口１２と排出口１２’は、互いに対向する辺に構成している。
ガス流路５、６および冷却水流路２４は、切削加工によって、セパレータ板の表面に形成する。例えば、本実施例のガス流路５は、幅２ｍｍ、深さ１ｍｍの溝を図２に示すような形状で、セパレータの面に刻んで形成した。
このようにして電池構成単位を５０個積層し、両端部に金属製の集電板と電気絶縁材料でできた絶縁板、さらにエンドプレートを順に配して積層電池を作製した。この積層体の上下にエンドプレートを配し、図８、２および３で説明した実施の形態の締結構造とした。すなわち、線径１ｍｍの金属線(線状部材)３９、エンドプレート３１および３２、補助プレート３４ならびにバネ３８で締結力を与える構造とした。バネ３８のバネ常数は５００ｋｇｆ／ｍｍであり、０．８ｍｍ圧縮して１カ所あたり４００ｋｇｆの締結圧力を加え、組立時の締結圧力を１３ｋｇｆ／ｃｍ²とした。感圧紙によりセパレータの圧力分布を調べたところ、全面にわたって均一な圧力分布となっていることが確認された。
本実施の形態によると、従来のセパレータ外側にロッドを配置して締結力を与える方法に比べ、セパレータの内側から締結力を印加することができるため、エンドプレートの変形が激減する。そのためエンドプレートの厚みを５ｍｍ以下にすることも可能である。
【００２４】
《実施の形態３》
本実施の形態おける燃料電池の締め付け構造を図９、２および３に示す。
単電池の積層体３０の上下にはエンドプレート３１および３２が配されている。出力端子（図示せず。）を有する積層体３０とエンドプレート３１および３２とは、特に図示していないが、絶縁手段によって電気的に絶縁されているものとする。エンドプレート３１、積層体３０およびエンドプレート３２は、弾性部材３９’を介して直列に接続された線状部材３９により締め付けられている。すなわち、これらを囲繞する形にかけられた線状部材３９、前記線状部材３９の端部を固定した固定部材３３、固定部材３３に設けたネジ穴に螺合させたネジ３５からなる締付け部材３５’により、積層体３０、エンドプレート３１および３２が締め付けられている。
線状部材３９を、積層体３０、エンドプレート３１および３２を囲繞する形に巻回し、線状部材３９にしかるべき張力を与えた後、固定部材３３およびネジ３５により線状部材３９を固定する。線状部材３９にしかるべき張力を与えた後締結することで、エンドプレートを介して積層体３０が締め付けられ、シール部や電極に必要な面圧がかけられる。なお、電極にガスを供給するためのガス供給口および冷却水供給口に対応する排出口は、供給口を有する側とは反対側の下面に設けられている。
【００２５】
つぎに、この実施の形態を具体化した例を以下に説明する。
まず、ＭＥＡの作製方法について説明する。炭素微粉末（米国キャボット社製のＶＸＣ７２、一次粒子経：３０ｎｍ、比表面積：２５４ｍ²／ｇ）に、平均粒径約３０Åの白金粒子を２５重量％担持したものを電極の触媒とした。この触媒粉末をイソプロパノールに分散させた分散液に、式（１）：

（式中、５≦ｘ≦１３．５、ｙ≒１０００、ｍ＝１、ｎ＝２である。）
【００２６】
で示されるパーフルオロカーボンスルホン酸の粉末をエチルアルコールに分散させた分散液を混合し、触媒ペーストを得た。
一方、電極の多孔性基材、すなわちガス拡散層を構成するカーボンペーパーを撥水処理した。厚み３６０μｍのカーボン不織布（東レ（株）製のＴＧＰ−Ｈ−１２０）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に含浸した後、これを乾燥し、４００℃で３０分間加熱することで、撥水性を与えた。
つぎに、炭素微粉末（電気化学工業（株）製のアセチレンブラックＨＳ−１００、一次粒子経：５３ｎｍ、比表面積：３７ｍ²／ｇ、ＤＢＰ吸油量：２００ｃｃ／１００ｇ）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に分散させ、炭素微粉末とポリテトラフルロエチレンの混合比（重量）を８７：１３としたペーストを得た。このペーストを上述のように撥水処理をしたカーボン不織布の両面に塗布し、乾燥した後、４００℃で３０分間加熱することで、炭素微粉末層を形成した。このとき、炭素微粉末層の一部は、カーボン不織布の中に埋まり込んでいた。このようにして作製したカーボン不織布と炭素微粉末層を合わせてガス拡散層１とした。
【００２７】
スクリーン印刷法を用いて、前記炭素微粉末層の上に前述の触媒ペーストを塗布して触媒層２を形成した。このようにして作製した触媒層２、炭素微粉末層およびカーボン不織布を合わせて電極とした。電極中に含まれる白金量は０．５ｍｇ／ｃｍ²、パーフルオロカーボンスルホン酸の量は１．２ｍｇ／ｃｍ²となるように調整した。この電極をアノード電極およびカソード電極の両方に使用した。
つぎに、外寸の大きさを前述の電極より５ｍｍ大きくした水素イオン伝導性高分子電解質膜（米国デュポン社製のナフィオン１１２）３の両面に、１対の電極を、触媒層２が電解質膜３に接するようにホットプレスで接合し、ＭＥＡを得た。このＭＥＡ２２を、その両面から気密性を有するカーボン製のセパレータ４で挟み込んで単電池の構成とした。セパレータ４の厚さは、４ｍｍであった。
【００２８】
以上の単電池を２セル積層して、電池構成単位を得た。冷却部のシール用Ｏリングは用いなかった。
電池構成単位のセパレータは、図２に示すように、一方の面に冷却水流路２４を配置し、他方の面にはガス流路６を配置したセパレータ４ａ、一方の面にガス流路５を配置し、他方の面にガス流路６を配置したセパレータ４ｂ、および一方の面にガス流路５を配置し、他方の面に冷却水流路２４を配置したセパレータ４ｃから構成されるものを用いた。また、図３に示すように、ガス流路の供給口１１および１３と排気口１１’および１３’ならびに冷却水流路の供給口１２と排出口１２’は、互いに対向する辺に構成している。
ガス流路５および６ならびに冷却水流路２４は、切削加工によって、セパレータ板の表面に形成する。例えば、本実施の形態のガス流路５は、幅２ｍｍ、深さ１ｍｍの溝を図２に示すような形状で、セパレータの面に刻んで形成した。
このようにして電池構成単位を５０個積層し、両端部に金属製の集電板と電気絶縁材料でできた絶縁板、さらにエンドプレートを順に配して積層電池を作製した。
この積層体の上下にエンドプレートを配し、図９、２および３で説明した実施の形態の締結構造とした。すなわち、弾性部材３９’を介して直列に接続された線径１ｍｍの金属線（線状部材）３９とエンドプレート３１および３２で締結力を与える構造とした。線状部材３９には２３００ｋｇｆの張力を与え、組立時の締結圧力を１３ｋｇｆ／ｃｍ²とした。感圧紙によりセパレータ板の圧力分布を調べたところ、全面にわたって均一な圧力分布となっていることが確認された。本実施の形態によると、従来のセパレータ板外側にロッドを配置して締結力を与える方法に比べ、セパレータ板の内側から締結力を印加することができるため、エンドプレートの変形が激減する。そのためエンドプレートの厚みを５ｍｍ以下にすることも可能である。
【００２９】
《実施の形態４》
本実施の形態おける燃料電池の締め付け構造を図１０、２および３に示す。
単電池の積層体３０の上下にはエンドプレート３１および３２が配されている。出力端子（図示せず。）を有する単電池の積層体３０とエンドプレート３１および３２とは、特に図示していないが、絶縁手段によって電気的に絶縁されているものとする。エンドプレート３１、積層体３０およびエンドプレート３２は、線状部材３９により締め付けられている。すなわち、これらを囲繞する形に巻回した線状部材３９、前記線状部材３９の端部を固定した固定部材３３、補助プレート３４、固定部材３３に設けたネジ穴に螺合させたネジ３５からなる締付け部材３５’により、積層体３０ならびにエンドプレート３１および３２が締め付けられている。ここで、補助プレート３４には、エンドプレート３２の底面に設けた凹部と対応させて凸部が設けられており（図示せず。）、凸部が凹部と嵌合する。また、補助プレート３４自体が板バネの機能を有する。
線状部材３９を電池積層体３０およびエンドプレート３１および３２ならびに補助プレート３４を囲繞する形に巻回し、線状部材３９にしかるべき張力を与えた後、固定部材３３およびネジ３５により線状部材３９を固定する。線状部材３９にしかるべき張力を与えた後締結することで、線状部材３９を支持している補助プレート３４が板バネとして機能し、歪み量に応じて締結力をエンドプレートを介して積層体３０に伝達する。その結果、エンドプレートが締め付けられ、シール部や電極に必要な面圧がかけられる。なお、電極にガスを供給するためのガス供給口ならびに冷却水供給口に対応する排出口は、供給口を有する側とは反対側の下面に設けられている。
【００３０】
つぎに、この実施の形態を具体化した例を以下に説明する。
まず、ＭＥＡの作製方法について説明する。炭素微粉末（米国キャボット社製のＶＸＣ７２、一次粒子経：３０ｎｍ、比表面積：２５４ｍ²／ｇ）に、平均粒径約３０Åの白金粒子を２５重量％担持したものを電極の触媒とした。この触媒粉末をイソプロパノールに分散させた分散液に、式（１）：

（式中、５≦ｘ≦１３．５、ｙ≒１０００、ｍ＝１、ｎ＝２である。）
【００３１】
で示されるパーフルオロカーボンスルホン酸の粉末をエチルアルコールに分散させた分散液を混合し、触媒ペーストを得た。
一方、電極の多孔性基材、すなわちガス拡散層を構成するカーボンペーパーを撥水処理した。厚み３６０μｍのカーボン不織布（東レ（株）製のＴＧＰ−Ｈ−１２０）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に含浸した後、これを乾燥し、４００℃で３０分間加熱することで、撥水性を与えた。
つぎに、炭素微粉末（電気化学工業（株）製のアセチレンブラックＨＳ−１００、一次粒子経：５３ｎｍ、比表面積：３７ｍ²／ｇ、ＤＢＰ吸油量：２００ｃｃ／１００ｇ）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に分散させ、炭素微粉末とポリテトラフルロエチレンの混合比（重量）を８７：１３としたペーストを得た。このペーストを上述のように撥水処理をしたカーボン不織布の両面に塗布し、乾燥した後、４００℃で３０分間加熱することで、炭素微粉末層を形成した。このとき、炭素微粉末層の一部は、カーボン不織布の中に埋まり込んでいた。このようにして作製したカーボン不織布と炭素微粉末層を合わせてガス拡散層１とした。
【００３２】
スクリーン印刷法を用いて、前記炭素微粉末層の上に前述の触媒ペーストを塗布して触媒層２を形成した。このようにして作製した触媒層２、炭素微粉末層およびカーボン不織布を合わせて電極とした。電極中に含まれる白金量は０．５ｍｇ／ｃｍ²、パーフルオロカーボンスルホン酸の量は１．２ｍｇ／ｃｍ²となるように調整した。この電極をアノード電極およびカソード電極の両方に使用した。
つぎに、外寸の大きさを前述の電極より５ｍｍ大きくした水素イオン伝導性高分子電解質膜（米国デュポン社製のナフィオン１１２）３の両面に、１対の電極を、触媒層２が電解質膜３に接するようにホットプレスで接合し、ＭＥＡを得た。このＭＥＡ２２を、その両面から気密性を有するカーボン製のセパレータ４で挟み込んで単電池の構成とした。セパレータ４の厚さは、４ｍｍであった。
【００３３】
以上の単電池を２セル積層して、電池構成単位を得た。冷却部のシール用Ｏリングは用いなかった。
電池構成単位のセパレータは、図２に示すように、一方の面に冷却水流路２４を配置し、他方の面にはガス流路６を配置したセパレータ４ａ、一方の面にガス流路５を配置し、他方の面にガス流路６を配置したセパレータ４ｂ、および一方の面にガス流路５を配置し、他方の面に冷却水流路２４を配置したセパレータ４ｃから構成されるものを用いた。また、図３に示すように、ガスの供給口１１および１３と排気口１１’および１３’ならびに冷却水の供給口１２と排出口１２’は、互いに対向する辺に構成している。
ガス流路５および６ならびに冷却水流路２４は、切削加工によって、セパレータ板の表面に形成する。例えば、本実施例のガス流路５は、幅２ｍｍ、深さ１ｍｍの溝を図２に示すような形状で、セパレータの面に刻んで形成した。
このようにして単電池を５０セル積層し、両端部に金属製の集電板と電気絶縁材料でできた絶縁板、さらにエンドプレートを順に配して積層電池を作製した。この積層体の上下にエンドプレートを配し、図１０、２および３で説明した実施の形態の締結構造とした。すなわち、線径１ｍｍの金属線（線状部材）３９とエンドプレート３１、３２、補助プレート３４で締結力を与える構造とした。補助プレート３４が有する板バネ機能のバネ常数は５００ｋｇｆ／ｍｍであり、０．８ｍｍ圧縮して線状部材１本あたり４００ｋｇｆの締結圧力を加え、組立時の締結圧力を１３ｋｇｆ／ｃｍ²とした。感圧紙によりセパレータ板の圧力分布を調べたところ、全面にわたって均一な圧力分布となっていることが確認された。本実施の形態によると、従来のセパレータ板外側にロッドを配置して締結力を与える方法に比べ、セパレータ板の内側から締結力を印加する事ができるため、エンドプレートの変形が激減する。そのためエンドプレートの厚みを５ｍｍ以下にすることも可能である。
【００３４】
《実施の形態５》
本実施の形態おける燃料電池の締め付け構造を図１１、２および３に示す。
単電池の積層体３０の上下にはエンドプレート３１および３２が配されている。出力端子（図示せず。）を有する単電池の積層体３０とエンドプレート３１および３２とは、特に図示していないが、絶縁手段によって電気的に絶縁されているものとする。エンドプレート３１、電池積層体３０およびエンドプレート３２は、複数の線状部材３９により締め付けられている。複数の線状部材を用いた他は、上記の実施の形態と同様である。
線状部材３９を電池積層体３０ならびにエンドプレート３１および３２を囲繞する形にかけ、線状部材３９にしかるべき張力を与えた後、固定部材３３およびネジ３５により線状部材３９を固定する。線状部材３９にしかるべき張力を与えた後締結することで、エンドプレートを介して積層体３０が締め付けられ、シール部や電極に必要な面圧がかけられる。電極にガスを供給するためのガス供給口ならびに冷却水供給口に対応する排出口は、供給口を有する側とは反対側の下面に設けられている。
【００３５】
つぎに、この実施の形態を具体化した例を以下に説明する。
まず、ＭＥＡの作製方法について説明する。炭素微粉末（米国キャボット社製のＶＸＣ７２、一次粒子経：３０ｎｍ、比表面積：２５４ｍ²／ｇ）に、平均粒径約３０Åの白金粒子を２５重量％担持したものを電極の触媒とした。この触媒粉末をイソプロパノールに分散させた分散液に、式（１）：

（式中、５≦ｘ≦１３．５、ｙ≒１０００、ｍ＝１、ｎ＝２である。）
【００３６】
で示されるパーフルオロカーボンスルホン酸の粉末をエチルアルコールに分散させた分散液を混合し、触媒ペーストを得た。
一方、電極の多孔性基材、すなわちガス拡散層を構成するカーボンペーパーを撥水処理した。厚み３６０μｍのカーボン不織布（東レ（株）製のＴＧＰ−Ｈ−１２０）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に含浸した後、これを乾燥し、４００℃で３０分間加熱することで、撥水性を与えた。
つぎに、炭素微粉末（電気化学工業（株）製のアセチレンブラックＨＳ−１００、一次粒子経：５３ｎｍ、比表面積：３７ｍ²／ｇ、ＤＢＰ吸油量：２００ｃｃ／１００ｇ）を、ポリテトラフルオロエチレン含有の水性ディスパージョン（ダイキン工業（株）製のネオフロンＮＤ１）に分散させ、炭素微粉末とポリテトラフルロエチレンの混合比（重量）を８７：１３としたペーストを得た。このペーストを上述のように撥水処理をしたカーボン不織布の両面に塗布し、乾燥した後、４００℃で３０分間加熱することで、炭素微粉末層を形成した。このとき、炭素微粉末層の一部は、カーボン不織布の中に埋まり込んでいた。このようにして作製したカーボン不織布と炭素微粉末層を合わせてガス拡散層１とした。
【００３７】
スクリーン印刷法を用いて、前記炭素微粉末層の上に前述の触媒ペーストを塗布して触媒層２を形成した。このようにして作製した触媒層２、炭素微粉末層およびカーボン不織布を合わせて電極とした。電極中に含まれる白金量は０．５ｍｇ／ｃｍ²、パーフルオロカーボンスルホン酸の量は１．２ｍｇ／ｃｍ²となるように調整した。この電極をアノード電極およびカソード電極の両方に使用した。
つぎに、外寸の大きさを前述の電極より５ｍｍ大きくした水素イオン伝導性高分子電解質膜（米国デュポン社製のナフィオン１１２）３の両面に、１対の電極を、触媒層２が電解質膜３に接するようにホットプレスで接合し、ＭＥＡを得た。このＭＥＡ２２を、その両面から気密性を有するカーボン製のセパレータ板４で挟み込んで単電池の構成とした。セパレータ板４の厚さは、４ｍｍであった。
【００３８】
以上の単電池を２セル積層して、電池構成単位を得た。冷却部のシール用Ｏリングは用いなかった。
電池構成単位のセパレータは、図２に示すように、一方の面に冷却水流路２４を配置し、他方の面にはガス流路６を配置したセパレータ４ａ、一方の面にガス流路５を配置し、他方の面にガス流路６を配置したセパレータ４ｂ、および一方の面にガス流路５を配置し、他方の面に冷却水流路２４を配置したセパレータ４ｃから構成されるものを用いた。また、図３に示すように、ガスの供給口１１および１３と排気口１１’および１３’ならびに冷却水の供給口１２と排出口１２’は、互いに対向する辺に構成している。
ガス流路５および６ならびに冷却水流路２４は、切削加工によって、セパレータの表面に形成する。例えば、本実施の形態のガス流路５は、幅２ｍｍ、深さ１ｍｍの溝を図２に示すような形状で、セパレータの面に刻んで形成した。
このようにして電池構成単位を５０個積層し、両端部に金属製の集電板と電気絶縁材料からなる絶縁板、さらにエンドプレートを順に配して積層電池を作製した。
この積層体の上下にエンドプレートを配し、図１１、２および３で説明した実施の形態の締結構造とした。すなわち、３本の線径１ｍｍの金属線（線状部材）３９とエンドプレート３１および３２で締結力を与える構造とした。３本の線状部材３９にはそれぞれ５７５ｋｇｆの張力を与え、組立時の締結圧力を１３ｋｇｆ／ｃｍ²とした。感圧紙によりセパレータ板の圧力分布を調べたところ、全面にわたって均一な圧力分布となっていることが確認された。本実施の形態によると、従来のセパレータ板外側にロッドを配置して締結力を与える方法に比べ、セパレータ板の内側から締結力を印加する事ができるため、エンドプレートの変形が激減する。そのためエンドプレートの厚みを５ｍｍ以下にすることも可能である。なお、ここでは３本の線状部材を用いたが、特にこれに限定されるものではない。
【００３９】
【発明の効果】
本発明によると、小型で簡易な構成の締結機構を実現し、かつ線状部材による締め付けによって組み付け工程の簡略化と積層された電池面内の面圧ばらつきを低減させることが可能になる。
【図面の簡単な説明】
【図１】本発明の一実施の形態に係る高分子電解質型燃料電池の概略斜視図である。
【図２】図１に示す燃料電池の要部を示す概略縦断面図である。
【図３】図１に示す燃料電池においてガスおよび冷却水の供給排出口の位置を示す図である。
【図４】従来の高分子電解質型燃料電池におけるシール方法を示す概略部分断面図である。
【図５】従来の高分子電解質型燃料電池における他のシール方法を示す概略部分断面図である。
【図６】従来の高分子電解質型燃料電池におけるさらに他のシール方法を示す概略部分断面図である。
【図７】内部マニホルド型の高分子電解質型燃料電池における電池構成単位の概略斜視図である。
【図８】本発明の別の実施の形態に係る高分子電解質型燃料電池の概略斜視図である。
【図９】本発明のさらに別の実施の形態に係る高分子電解質型燃料電池の概略斜視図である。
【図１０】本発明のさらに別の実施の形態に係る高分子電解質型燃料電池の概略斜視図である。
【図１１】本発明のさらに別の実施の形態に係る高分子電解質型燃料電池の概略斜視図である。
【符号の説明】
１ 拡散層
２ 触媒反応層
３ 高分子電解質膜
４ セパレータ
５、６ ガス流路
１１、１３ ガス供給口
１１’、１３’ガス排出口
１２ 冷却水供給口
１２’ 冷却水排出口
１６ ガスケット
１７ シール材
１８ Ｏリング
１９ ガスケット
２１ 樹脂
２２ ＭＥＡ
２３ 電極
２４ 冷却水流路
２５ シール部
３０ 積層体
３１、３２ エンドプレート
３３ 固定部材
３４ 補助プレート
３５ ネジ
３５’ 締付け部材
３８ バネ
３９ 線状部材
３９’ 弾性部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel cell used for a portable power source, a power source for an electric vehicle, a domestic cogeneration system, and the like, particularly a polymer electrolyte fuel cell, and a method for manufacturing the same.
[0002]
[Prior art]
A polymer electrolyte fuel cell is one in which a fuel gas such as hydrogen and an oxidant gas such as air are electrochemically reacted by a gas diffusion electrode, and generates electricity and heat simultaneously.
A schematic partial cross-sectional view of this type of polymer electrolyte fuel cell is shown in FIG.
On both surfaces of the polymer electrolyte membrane 3 that selectively transports hydrogen ions, a catalytic reaction layer (hereinafter, also simply referred to as “catalyst layer”) 2 composed mainly of carbon powder carrying a platinum-based metal catalyst is provided. Closely arranged. Further, a pair of gas diffusion layers 1 having both gas permeability and conductivity are disposed in close contact with the outer surface of the catalyst reaction layer 2. The diffusion layer 1 and the catalytic reaction layer 2 constitute an electrode 23.
[0003]
An electrode electrolyte membrane assembly (hereinafter referred to as “MEA”) 22 composed of the electrode 23 and the electrolyte membrane 3 is mechanically fixed outside the electrode 23, and adjacent MEAs 22 are electrically connected in series with each other. A plate-like conductive separator 4 for connection is provided. A gas flow path 5 for supplying a reaction gas to the electrode and carrying away a gas generated by the reaction or surplus gas is formed in a portion of the separator 4 that contacts the electrode 23. The gas flow path 5 can be provided separately from the separator, but a system in which a groove is provided on the surface of the separator to form a gas flow path is common.
On the other surface of the separator 4 disposed every two cells, a cooling water passage 24 for circulating cooling water for keeping the battery temperature constant is provided. By circulating the cooling water in this way, the heat energy generated by the reaction is used in the form of hot water or the like.
In order to prevent hydrogen and air from leaking out of the battery and mixing with each other, and further to prevent cooling water from leaking out of the battery, the polymer electrolyte membrane 3 is sandwiched between the electrode 23 and the sealing material 17 or O. A ring 18 is arranged.
[0004]
Another sealing method is shown in FIG. FIG. 5 is a schematic partial cross-sectional view of another conventional polymer electrolyte fuel cell. As shown in FIG. 5, a gasket 19 made of resin or a metal plate having the same thickness as the electrode is arranged around the electrode, and the gap between the gasket 19 and the separator 4 is sealed with grease or an adhesive. There is also a structure (not shown).
Further, in recent years, an MEA 22 using an electrode 23 having the same size as that of the polymer electrolyte membrane 3 is used, and a resin 21 having a sealing effect is previously impregnated into a portion where a gas seal is required as shown in FIG. A method has been devised in which a gas sealing property between the separator 4 and the separator 4 is ensured by using a solidified material. FIG. 6 is a schematic partial cross-sectional view of another conventional polymer electrolyte fuel cell.
[0005]
Many fuel cells have a laminated structure in which a large number of single cells are stacked. In order to discharge heat generated along with electric power outside the battery during operation of the fuel cell, in the stacked battery, a cooling plate is arranged for each unit cell or cell. The cooling plate generally has a structure in which a heat medium such as cooling water flows through a thin metal plate. Moreover, as shown in FIGS. 4-6, there also exists a method of forming a flow path in the back surface of the separator 4 which comprises a single cell, ie, the surface which wants to flow a cooling water, and making separator 4 itself function as a cooling plate. At that time, an O-ring and a gasket are also required to seal a heat medium such as cooling water. With this sealing method, sufficient conductivity is ensured between the upper and lower sides of the cooling plate by completely crushing the O-ring. There is a need.
[0006]
In such a laminated battery, a so-called internal manifold type in which a gas supply hole and a gas discharge hole to each unit cell, called a manifold, and a cooling water supply / discharge hole are secured inside the laminated battery is generally used.
FIG. 7 shows a schematic perspective view of a unit cell stack of a polymer electrolyte fuel cell employing an internal manifold.
Similar to the fuel cell shown in FIG. 4, the diffusion layer 1, the catalytic reaction layer 2, the polymer electrolyte membrane 3, and the separator 4 are laminated to form a gas flow path 5. A manifold 8 for supplying or exhausting gas to the battery and a manifold 8 ′ for supplying or discharging water for cooling the battery to the battery are formed.
However, in the internal manifold type, when the battery is operated using the reformed gas, the CO concentration increases in the downstream area of the fuel gas flow path of each battery. As a result, the temperature decreases due to electrode poisoning, and the temperature decreases. This further promotes electrode poisoning.
In order to alleviate such a phenomenon of battery performance degradation, the external manifold type has been reconsidered as a structure in which the opening for supplying and discharging gas from the manifold to each unit cell can be taken as wide as possible.
[0007]
In the case of an internal manifold type fuel cell, since a constant clamping pressure is applied to the entire cell, the reliability of the gas seal is generally high. On the other hand, in the case of an external manifold type fuel cell, since the side surface of the laminated battery in contact with the flange surface of the manifold is a laminated body of thin plates such as MEAs and separators, it is difficult to obtain a smooth sealing surface. The reliability of the gas seal is low compared to the system.
However, in the case of the internal manifold system, when the number of stacked batteries and the power output increase, a large amount of fluid must be supplied and discharged through the internal manifold holes, and the pressure loss at the manifold portion increases. Therefore, for fuel cells with a small number of stacks, considering the compactness of the entire cell, it is necessary to use manifold holes with a small hole diameter. Conversely, for fuel cells with a large number of stacks, it is necessary to use manifold holes with a large hole diameter to suppress pressure loss. is there. Therefore, the internal manifold system has a problem that the number of stacks must always be considered in the design of separators and MEAs.
[0008]
In any case, it is necessary to stack a large number of single cells including a cooling unit in one direction, arrange two end plates at both ends thereof, and fix the two end plates with a fastening rod. As a tightening method, it is desirable to tighten the cells as uniformly as possible in the plane. From the viewpoint of mechanical strength, a metal material such as stainless steel is usually used for the end plate and the fastening rod. These end plates and fastening rods and the laminated battery are electrically insulated by an insulating plate or the like, and have a structure in which current does not leak outside through the end plates. As for the fastening rod, an improved system has also been proposed in which it passes through a through hole formed in the separator plate or the whole laminated battery is fastened with a metal belt over the end plate.
Further, in any of the sealing methods shown in FIGS. 4 to 6, a constant clamping pressure is required to maintain the sealing performance and to keep the contact resistance between the electrode and the separator small. A configuration such as inserting a screw spring or a disc spring between them is adopted. In addition, this tightening pressure ensures electrical contact between members constituting the battery, such as a separator, an electrode, and an electrolyte membrane.
[0009]
[Problems to be solved by the invention]
As described above, in the conventional fuel cell, in order to seal a gas such as hydrogen gas or air, it is necessary to arrange a sealing material or an O-ring around the electrode. Therefore, a structure is adopted in which the sealing effect is maintained by sandwiching the sealing material or the sealing portion between the upper and lower separator plates, and it is necessary to constantly apply a relatively large tightening force. However, a tightening mechanism such as an end plate or a tightening rod tends to be long, and there is a problem that the weight is increased and the weight reduction of the entire fuel cell is hindered.
Furthermore, the tightening force must be managed when a plurality of tightening rods are fastened, the cost increases due to an increase in the assembly process, and the battery performance varies due to variations in surface pressure with respect to the stacked batteries.
In addition, since pressure is applied to the seal part and the electrode part for a long period of time, the constituent members are distorted, and as a result, the surface pressure required for the seal part and the electrode is reduced. Thus, a configuration is adopted in which a spring is installed at the end of the tightening rod and fastened. For this reason, it was an obstacle to miniaturization.
In view of the above problems, an object of the present invention is to provide a polymer electrolyte fuel cell provided with a tightening mechanism for a laminated battery having a small and simple configuration.
[0010]
[Means for Solving the Problems]
According to the present invention, a unit cell comprising a polymer electrolyte membrane and a pair of electrodes having a catalytic reaction layer sandwiching the polymer electrolyte membrane is oxidized to a means for supplying and distributing fuel gas to one of the electrodes and to the other of the electrodes. A polymer electrolyte fuel cell comprising a laminate in which a plurality of conductive separators are stacked via a conductive separator having a means for supplying and distributing the agent gas, the first end plate at one end of the laminate, An assembly comprising a second end plate disposed at the other end and comprising the laminate, the first end plate, and the second end plate Spiral on the outer surface of the The present invention relates to a polymer electrolyte fuel cell characterized in that the laminate is fastened by a wound linear member.
Furthermore, the present invention provides a unit cell comprising a polymer electrolyte membrane and a pair of electrodes having a catalytic reaction layer sandwiching the polymer electrolyte membrane, a means for supplying and distributing fuel gas to one of the electrodes, and the other of the electrodes And a means for supplying and distributing an oxidant gas to a polymer electrolyte fuel cell comprising a plurality of laminated bodies via a conductive separator, wherein a first end is provided at one end of the laminated body. A plate, a second end plate disposed at the other end, and an elastic member for compressing the laminate in the laminating direction and at least one of the first end plate and the second end plate in the laminating direction An auxiliary plate that is pressed against the laminated body, and an assembly comprising the laminate, the first end plate, the second end plate, the elastic member, and the auxiliary plate Spiral on the outer surface of the The present invention also relates to a polymer electrolyte fuel cell characterized in that the laminated body is fastened by a wound linear member.
In the fuel cell, it is effective to fix the end of the linear member through an elastic member.
Further, it is effective that the auxiliary plate is made of an elastic metal plate and also serves as the elastic member.
Furthermore, it is also effective to fasten the laminated body with a plurality of linear members.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The greatest feature of the present invention is that a linear member is used for the fastening mechanism of the laminate, thereby realizing a fastening mechanism with a small and simple configuration, and simplifying the assembly process by fastening with the linear member. It was made possible to reduce variations in surface pressure in the stacked battery surface.
In other words, the polymer electrolyte fuel cell of the present invention is characterized in that a laminated body in which a plurality of unit cells are stacked via a conductive separator is fastened by winding it with a linear member. . Thereby, in the laminated body which comprises a fuel cell, members located in edge parts, such as an end plate, can be restrained and it can restrict | limit that both separate.
Therefore, for example, when the first end plate is arranged at one end of the laminate and the second end plate is arranged at the other end, the laminate, the first end plate, and the second end plate are separated from each other. The linear member may be wound around the assembly, and the end of the linear member may be fixed to one of the end plates.
Examples of the material constituting the linear member include metal wires such as piano wires, hard steel wires, PC wires, and PC hard steel wires. Among these, the tensile strength is 1000 N / mm ² The above is preferable.
Moreover, it is preferable to fix one end part of a linear member with the fixing member which has a function which can adjust the tension | tensile_strength of the wound linear member. For example, the end of the linear member may be connected in series with an elastic member such as a coil spring or a belt-like rubber, and the elastic member may be fixed to the fixing member. As the fixing member, for example, on a substrate made of a metal plate, a linear member or an elastic member may be sandwiched by a metal plate serving as a tightening member and fixed with a screw.
[0012]
In the fuel cell according to the present invention, an elastic member that compresses the laminated body in the laminating direction and an auxiliary plate that presses the elastic member in the laminating direction are provided on at least one of the first end plate and the second end plate. It is effective to distribute.
When such a structure is employed, the stone laminate can be fastened while uniformly applying pressure to the surface of the laminate. Further, since the linear member is wound around the laminate, a fastening force can be applied from the inside of the separator in the laminate. Therefore, deformation of the end plate can be suppressed as compared with a method in which a rod is provided outside the separator and fastened.
In particular, it is effective to use an elastic metal plate such as a leaf spring as the auxiliary plate.
Furthermore, in the present invention, a plurality of linear members may be wound around the laminate. In this case, curing is achieved that the fastening force to the laminate is more uniformly applied to the surface.
Hereinafter, the present invention will be described more specifically with reference to the drawings.
[0013]
Embodiment 1
The fuel cell according to the present embodiment will be described with reference to FIGS. In particular, the clamping mechanism is shown in FIG.
In FIG. 1, end plates 31 and 32 are arranged above and below a cell stack 30. Although not shown in particular, the unit cell stack 30 having output terminals (not shown) and the end plates 31 and 32 are electrically insulated by an insulating means. The end plate 31, the laminated body 30 and the end plate 32 are fastened by a linear member 39. That is, it comprises a linear member 39 wound so as to surround the laminate 30, a fixing member 33 that fixes the end of the linear member 39, and a screw 35 that is screwed into a screw hole provided in the fixing member 33. The battery stack 30 and the end plates 31 and 32 are fastened by the fastening member 35 ′.
The linear member 39 is wound so as to surround the laminated body 30 and the end plates 31 and 32, and after applying appropriate tension to the linear member 39, the linear member 39 is fixed by the fixing member 33 and the screw 35. By applying an appropriate tension to the linear member 39 and then fastening it, the laminate 30 is fastened via the end plate, and a necessary surface pressure is applied to the seal portion and the electrode.
The fuel cell of the present invention has a gas supply port for supplying gas to the electrode and a cooling water supply port. The gas and cooling water discharge port is provided on the lower surface opposite to the side having the supply port.
[0014]
Next, an example in which this embodiment is embodied will be described below.
First, a method for manufacturing the MEA will be described (see FIG. 2). Carbon fine powder (VXC72 manufactured by Cabot, USA, primary particle size: 30 nm, specific surface area: 254 m ² / G) was loaded with 25% by weight of platinum particles having an average particle size of about 30 mm as an electrode catalyst. In a dispersion obtained by dispersing this catalyst powder in isopropanol, the formula (1):

(Wherein 5 ≦ x ≦ 13.5, y≈1000, m = 1, n = 2)
[0015]
A dispersion obtained by dispersing the perfluorocarbonsulfonic acid powder represented by the formula (2) in ethyl alcohol was mixed to obtain a catalyst paste.
On the other hand, the porous substrate of the electrode, that is, the carbon paper constituting the gas diffusion layer was subjected to water repellent treatment. A carbon non-woven fabric having a thickness of 360 μm (TGP-H-120 manufactured by Toray Industries, Inc.) was impregnated with an aqueous dispersion containing polytetrafluoroethylene (Neolon ND1 manufactured by Daikin Industries, Ltd.), and then dried. Water repellency was imparted by heating at 400 ° C. for 30 minutes.
Next, fine carbon powder (acetylene black HS-100 manufactured by Denki Kagaku Kogyo Co., Ltd., primary particle diameter: 53 nm, specific surface area: 37 m ² / G, DBP oil absorption: 200 cc / 100 g) is dispersed in a polytetrafluoroethylene-containing aqueous dispersion (Nephron ND1 manufactured by Daikin Industries, Ltd.), and the mixing ratio of carbon fine powder and polytetrafluoroethylene ( A paste with a weight) of 87:13 was obtained. The paste was applied to both sides of the carbon non-woven fabric subjected to water repellent treatment as described above, dried, and then heated at 400 ° C. for 30 minutes to form a carbon fine powder layer. At this time, a part of the carbon fine powder layer was embedded in the carbon nonwoven fabric. Thus, the produced carbon nonwoven fabric and the carbon fine powder layer were combined to make a gas diffusion layer 1.
[0016]
Using the screen printing method, the catalyst paste 2 was applied on the carbon fine powder layer to form the catalyst layer 2. The catalyst layer 2, the carbon fine powder layer, and the carbon non-woven fabric thus produced were combined to form an electrode. The amount of platinum contained in the electrode is 0.5 mg / cm ² The amount of perfluorocarbon sulfonic acid is 1.2 mg / cm ² It adjusted so that it might become. This electrode was used for both the anode and cathode electrodes.
Next, a pair of electrodes are provided on both sides of a hydrogen ion conductive polymer electrolyte membrane (Nafion 112 manufactured by DuPont, USA) 3 whose outer size is 5 mm larger than that of the aforementioned electrode, and the catalyst layer 2 is an electrolyte membrane. 3 was joined by hot press so as to be in contact with 3 to obtain MEA. The MEA 22 was sandwiched between carbon separators 4 having airtightness from both sides to form a unit cell. The thickness of the separator 4 was 4 mm.
[0017]
Two cells of the above unit cells were stacked to obtain a battery constituent unit. The O-ring for sealing the cooling part was not used.
As shown in FIG. 2, the separator of the battery constituent unit is a separator 4a in which a cooling water channel 24 is arranged on one surface and a gas channel 6 is arranged on the other surface, and a gas channel 5 on one surface. And the separator 4b in which the gas channel 6 is arranged on the other surface, and the separator 4c in which the gas channel 5 is arranged on one surface and the cooling water channel 24 is arranged on the other surface are used. . Further, as shown in FIG. 3, the gas supply ports 11 and 13 and the exhaust ports 11 ′ and 13 ′, and the cooling water supply port 12 and the discharge port 12 ′ are provided on opposite sides. In FIG. 3, details of the linear members and the like are omitted.
The gas flow paths 5 and 6 and the cooling water flow path 24 can be formed on the surface of the separator by cutting. In this example, a groove having a shape as shown in FIG. 2 and a width of 2 mm and a depth of 1 mm was formed as a gas flow path 5 on the surface of the separator.
[0018]
Thus, the metal current collecting plate 52, the insulating plate 51 made of an electric insulating material, and the end plates 31 and 32 were arranged in this order on both ends of the laminated body in which 50 battery constituent units were laminated. Furthermore, end plates were arranged above and below the laminate, and the fastening structure of the embodiment described with reference to FIGS. That is, a metal wire having a wire diameter of 1 mm was used as the linear member 39, and a fastening force was applied via the end plates 31 and 32. The linear member 39 is given a tension of 2300 kgf, and the fastening pressure during assembly is 13 kgf / cm. ² It was. When the pressure distribution of the separator plate was examined using pressure sensitive paper, it was confirmed that the pressure distribution was uniform over the entire surface.
According to the present embodiment, compared to a conventional method in which a rod is disposed outside the separator to provide a fastening force, the fastening force can be applied from the inside of the separator, so that the deformation of the end plate is drastically reduced. Therefore, the thickness of the end plate can be 5 mm or less.
[0019]
<< Embodiment 2 >>
A fuel cell according to the present embodiment is shown in FIGS. In particular, the tightening structure employed is shown in FIG.
End plates 31 and 32 are arranged above and below the cell stack 30. Although not shown in particular, the unit cell stack 30 having output terminals (not shown) and the end plates 31 and 32 are electrically insulated by an insulating means. The end plate 31, the battery stack 30 and the end plate 32 are fastened by a linear member 39. That is, the linear member 39 wound so as to surround the laminated body 30, the fixing member 33 fixing the end of the linear member 39, and the convex provided corresponding to the concave portion 36 provided on the bottom surface of the end plate 32. The laminated body 30 and the end plates 31 and 32 are fastened by a fastening member 35 ′ comprising an auxiliary plate 34 with a spring 38 attached to the portion 37 and a screw 35 screwed into a screw hole provided in the fixing member 33. The spring 38 may be a disc spring.
The linear member 39 is wound around the laminate 30, the end plates 31 and 32 and the auxiliary plate 34, and after applying appropriate tension to the linear member 39, the linear member 39 is fixed by the fixing member 33 and the screw 35. To fix. By applying an appropriate tension to the linear member 39 and then fastening it, the laminate 30 is fastened via the end plate, and a necessary surface pressure is applied to the seal portion and the electrode.
A gas supply port for supplying gas to the electrode and a discharge port corresponding to the cooling water supply port are provided on the lower surface opposite to the side having the supply port.
[0020]
Next, an example in which this embodiment is embodied will be described below.
First, a method for manufacturing the MEA will be described. Carbon fine powder (VXC72 manufactured by Cabot, USA, primary particle size: 30 nm, specific surface area: 254 m ² / G) was loaded with 25% by weight of platinum particles having an average particle size of about 30 mm as an electrode catalyst. In a dispersion obtained by dispersing this catalyst powder in isopropanol, the formula (1):

(Wherein 5 ≦ x ≦ 13.5, y≈1000, m = 1, n = 2)
[0021]
A dispersion obtained by dispersing the perfluorocarbonsulfonic acid powder represented by the formula (2) in ethyl alcohol was mixed to obtain a catalyst paste.
On the other hand, the porous substrate of the electrode, that is, the carbon paper constituting the gas diffusion layer was subjected to water repellent treatment. A carbon non-woven fabric having a thickness of 360 μm (TGP-H-120 manufactured by Toray Industries, Inc.) was impregnated with an aqueous dispersion containing polytetrafluoroethylene (Neolon ND1 manufactured by Daikin Industries, Ltd.), and then dried. Water repellency was imparted by heating at 400 ° C. for 30 minutes.
Next, fine carbon powder (acetylene black HS-100 manufactured by Denki Kagaku Kogyo Co., Ltd., primary particle diameter: 53 nm, specific surface area: 37 m ² / G, DBP oil absorption: 200 cc / 100 g) is dispersed in a polytetrafluoroethylene-containing aqueous dispersion (Nephron ND1 manufactured by Daikin Industries, Ltd.), and the mixing ratio of carbon fine powder and polytetrafluoroethylene ( A paste with a weight) of 87:13 was obtained. The paste was applied to both sides of the carbon non-woven fabric subjected to water repellent treatment as described above, dried, and then heated at 400 ° C. for 30 minutes to form a carbon fine powder layer. At this time, a part of the carbon fine powder layer was embedded in the carbon nonwoven fabric. Thus, the produced carbon nonwoven fabric and the carbon fine powder layer were combined to make a gas diffusion layer 1.
[0022]
Using the screen printing method, the catalyst paste 2 was applied on the carbon fine powder layer to form the catalyst layer 2. The catalyst layer 2, the carbon fine powder layer, and the carbon non-woven fabric thus produced were combined to form an electrode. The amount of platinum contained in the electrode is 0.5 mg / cm ² The amount of perfluorocarbon sulfonic acid is 1.2 mg / cm ² It adjusted so that it might become. This electrode was used for both the anode and cathode electrodes.
Next, a pair of electrodes are provided on both sides of a hydrogen ion conductive polymer electrolyte membrane (Nafion 112 manufactured by DuPont, USA) 3 whose outer size is 5 mm larger than that of the aforementioned electrode, and the catalyst layer 2 is an electrolyte membrane. 3 was joined by hot press so as to be in contact with 3 to obtain MEA.
The MEA 22 was sandwiched between carbon separators 4 having airtightness from both sides to form a unit cell. The thickness of the separator 4 was 4 mm.
[0023]
Two cells of the above unit cells were stacked to obtain a battery constituent unit. The O-ring for sealing the cooling part was not used.
As shown in FIG. 2, the separator of the battery unit has a separator 4a in which a cooling water channel 24 is arranged on one surface, a gas channel 6 is arranged on the other surface, and a gas channel 5 is arranged on one surface. A separator 4b having a gas flow path 6 disposed on the other surface and a separator 4c having the gas flow path 5 disposed on one surface and the cooling water flow path 24 disposed on the other surface. It was. Moreover, as shown in FIG. 3, the supply ports 11 and 13 and the exhaust ports 11 ′ and 13 ′ of the gas path and the supply port 12 and the discharge port 12 ′ of the cooling water are configured on opposite sides.
The gas flow paths 5 and 6 and the cooling water flow path 24 are formed on the surface of the separator plate by cutting. For example, the gas flow path 5 of the present example was formed by cutting a groove having a width of 2 mm and a depth of 1 mm into the shape of the separator as shown in FIG.
In this way, 50 battery constituent units were stacked, and a laminated battery was manufactured by sequentially arranging a metal current collector plate, an insulating plate made of an electrically insulating material, and an end plate at both ends. End plates are arranged on the top and bottom of the laminate, and the fastening structure of the embodiment described with reference to FIGS. In other words, the metal wire (linear member) 39 having a wire diameter of 1 mm, the end plates 31 and 32, the auxiliary plate 34, and the spring 38 give a fastening force. The spring constant of the spring 38 is 500 kgf / mm, compressed by 0.8 mm, and a fastening pressure of 400 kgf per place is applied, and the fastening pressure during assembly is 13 kgf / cm. ² It was. When the pressure distribution of the separator was examined using pressure sensitive paper, it was confirmed that the pressure distribution was uniform over the entire surface.
According to the present embodiment, compared to a conventional method in which a rod is disposed outside the separator to provide a fastening force, the fastening force can be applied from the inside of the separator, so that the deformation of the end plate is drastically reduced. Therefore, the thickness of the end plate can be 5 mm or less.
[0024]
<< Embodiment 3 >>
FIGS. 9, 2 and 3 show the fastening structure of the fuel cell in the present embodiment.
End plates 31 and 32 are arranged above and below the cell stack 30. Although not shown in particular, the laminated body 30 having an output terminal (not shown) and the end plates 31 and 32 are electrically insulated by an insulating means. The end plate 31, the laminate 30 and the end plate 32 are fastened by a linear member 39 connected in series via an elastic member 39 ′. That is, a tightening member 35 including a linear member 39 that surrounds them, a fixing member 33 that fixes the end of the linear member 39, and a screw 35 that is screwed into a screw hole provided in the fixing member 33. The laminate 30 and the end plates 31 and 32 are tightened by '.
The linear member 39 is wound around the laminated body 30 and the end plates 31 and 32, and after applying appropriate tension to the linear member 39, the linear member 39 is fixed by the fixing member 33 and the screw 35. . By applying an appropriate tension to the linear member 39 and then fastening it, the laminate 30 is fastened via the end plate, and a necessary surface pressure is applied to the seal portion and the electrode. The gas supply port for supplying gas to the electrode and the discharge port corresponding to the cooling water supply port are provided on the lower surface opposite to the side having the supply port.
[0025]
Next, an example in which this embodiment is embodied will be described below.
First, a method for manufacturing the MEA will be described. Carbon fine powder (VXC72 manufactured by Cabot, USA, primary particle size: 30 nm, specific surface area: 254 m ² / G) was loaded with 25% by weight of platinum particles having an average particle size of about 30 mm as an electrode catalyst. In a dispersion obtained by dispersing this catalyst powder in isopropanol, the formula (1):

(Wherein 5 ≦ x ≦ 13.5, y≈1000, m = 1, n = 2)
[0026]
A dispersion obtained by dispersing the perfluorocarbonsulfonic acid powder represented by the formula (2) in ethyl alcohol was mixed to obtain a catalyst paste.
On the other hand, the porous substrate of the electrode, that is, the carbon paper constituting the gas diffusion layer was subjected to water repellent treatment. A carbon non-woven fabric having a thickness of 360 μm (TGP-H-120 manufactured by Toray Industries, Inc.) was impregnated with an aqueous dispersion containing polytetrafluoroethylene (Neolon ND1 manufactured by Daikin Industries, Ltd.), and then dried. Water repellency was imparted by heating at 400 ° C. for 30 minutes.
Next, fine carbon powder (acetylene black HS-100 manufactured by Denki Kagaku Kogyo Co., Ltd., primary particle diameter: 53 nm, specific surface area: 37 m ² / G, DBP oil absorption: 200 cc / 100 g) is dispersed in a polytetrafluoroethylene-containing aqueous dispersion (Nephron ND1 manufactured by Daikin Industries, Ltd.), and the mixing ratio of carbon fine powder and polytetrafluoroethylene ( A paste with a weight) of 87:13 was obtained. The paste was applied to both sides of the carbon non-woven fabric subjected to water repellent treatment as described above, dried, and then heated at 400 ° C. for 30 minutes to form a carbon fine powder layer. At this time, a part of the carbon fine powder layer was embedded in the carbon nonwoven fabric. Thus, the produced carbon nonwoven fabric and the carbon fine powder layer were combined to make a gas diffusion layer 1.
[0027]
Using the screen printing method, the catalyst paste 2 was applied on the carbon fine powder layer to form the catalyst layer 2. The catalyst layer 2, the carbon fine powder layer, and the carbon non-woven fabric thus produced were combined to form an electrode. The amount of platinum contained in the electrode is 0.5 mg / cm ² The amount of perfluorocarbon sulfonic acid is 1.2 mg / cm ² It adjusted so that it might become. This electrode was used for both the anode and cathode electrodes.
Next, a pair of electrodes are provided on both sides of a hydrogen ion conductive polymer electrolyte membrane (Nafion 112 manufactured by DuPont, USA) 3 whose outer size is 5 mm larger than that of the aforementioned electrode, and the catalyst layer 2 is an electrolyte membrane. 3 was joined by hot press so as to be in contact with 3 to obtain MEA. The MEA 22 was sandwiched between carbon separators 4 having airtightness from both sides to form a unit cell. The thickness of the separator 4 was 4 mm.
[0028]
Two cells of the above unit cells were stacked to obtain a battery constituent unit. The O-ring for sealing the cooling part was not used.
As shown in FIG. 2, the separator of the battery unit has a separator 4a in which a cooling water channel 24 is arranged on one surface, a gas channel 6 is arranged on the other surface, and a gas channel 5 is arranged on one surface. A separator 4b having a gas flow path 6 disposed on the other surface and a separator 4c having the gas flow path 5 disposed on one surface and the cooling water flow path 24 disposed on the other surface. It was. Further, as shown in FIG. 3, the supply ports 11 and 13 and the exhaust ports 11 ′ and 13 ′ of the gas flow channel and the supply port 12 and the discharge port 12 ′ of the cooling water flow channel are configured on opposite sides. .
The gas flow paths 5 and 6 and the cooling water flow path 24 are formed on the surface of the separator plate by cutting. For example, the gas flow path 5 of the present embodiment is formed by cutting a groove having a width of 2 mm and a depth of 1 mm into the shape of the separator as shown in FIG.
In this way, 50 battery constituent units were stacked, and a laminated battery was manufactured by sequentially arranging a metal current collector plate, an insulating plate made of an electrically insulating material, and an end plate at both ends.
End plates are arranged on the top and bottom of the laminate, and the fastening structure of the embodiment described with reference to FIGS. That is, the structure is such that a fastening force is applied by the metal wire (linear member) 39 having a wire diameter of 1 mm and the end plates 31 and 32 connected in series via the elastic member 39 ′. The linear member 39 is given a tension of 2300 kgf, and the fastening pressure during assembly is 13 kgf / cm. ² It was. When the pressure distribution of the separator plate was examined using pressure sensitive paper, it was confirmed that the pressure distribution was uniform over the entire surface. According to the present embodiment, compared to a conventional method in which a rod is arranged outside the separator plate to give a fastening force, the fastening force can be applied from the inside of the separator plate, so that the deformation of the end plate is drastically reduced. Therefore, the thickness of the end plate can be 5 mm or less.
[0029]
<< Embodiment 4 >>
FIGS. 10, 2 and 3 show the fastening structure of the fuel cell in the present embodiment.
End plates 31 and 32 are arranged above and below the cell stack 30. Although not shown in particular, the cell stack 30 and the end plates 31 and 32 having output terminals (not shown) are electrically insulated by an insulating means. The end plate 31, the laminated body 30 and the end plate 32 are fastened by a linear member 39. That is, the linear member 39 wound so as to surround them, the fixing member 33 fixing the end of the linear member 39, the auxiliary plate 34, and the screw 35 screwed into the screw hole provided in the fixing member 33. The laminated body 30 and the end plates 31 and 32 are fastened by a fastening member 35 ′ composed of Here, the auxiliary plate 34 is provided with a convex portion (not shown) corresponding to the concave portion provided on the bottom surface of the end plate 32, and the convex portion is fitted with the concave portion. Further, the auxiliary plate 34 itself has a function of a leaf spring.
The linear member 39 is wound around the battery stack 30, the end plates 31 and 32, and the auxiliary plate 34, and after applying appropriate tension to the linear member 39, the linear member 39 is fixed by the fixing member 33 and the screw 35. 39 is fixed. By fastening after applying appropriate tension to the linear member 39, the auxiliary plate 34 supporting the linear member 39 functions as a leaf spring, and the fastening force is stacked via the end plate according to the amount of strain. Transmitted to the body 30. As a result, the end plate is tightened, and a necessary surface pressure is applied to the seal portion and the electrode. A gas supply port for supplying gas to the electrode and a discharge port corresponding to the cooling water supply port are provided on the lower surface opposite to the side having the supply port.
[0030]
Next, an example in which this embodiment is embodied will be described below.
First, a method for manufacturing the MEA will be described. Carbon fine powder (VXC72 manufactured by Cabot, USA, primary particle size: 30 nm, specific surface area: 254 m ² / G) was loaded with 25% by weight of platinum particles having an average particle size of about 30 mm as an electrode catalyst. In a dispersion obtained by dispersing this catalyst powder in isopropanol, the formula (1):

(Wherein 5 ≦ x ≦ 13.5, y≈1000, m = 1, n = 2)
[0031]
A dispersion obtained by dispersing the perfluorocarbonsulfonic acid powder represented by the formula (2) in ethyl alcohol was mixed to obtain a catalyst paste.
On the other hand, the porous substrate of the electrode, that is, the carbon paper constituting the gas diffusion layer was subjected to water repellent treatment. A carbon non-woven fabric having a thickness of 360 μm (TGP-H-120 manufactured by Toray Industries, Inc.) was impregnated with an aqueous dispersion containing polytetrafluoroethylene (Neolon ND1 manufactured by Daikin Industries, Ltd.), and then dried. Water repellency was imparted by heating at 400 ° C. for 30 minutes.
Next, fine carbon powder (acetylene black HS-100 manufactured by Denki Kagaku Kogyo Co., Ltd., primary particle diameter: 53 nm, specific surface area: 37 m ² / G, DBP oil absorption: 200 cc / 100 g) is dispersed in a polytetrafluoroethylene-containing aqueous dispersion (Nephron ND1 manufactured by Daikin Industries, Ltd.), and the mixing ratio of carbon fine powder and polytetrafluoroethylene ( A paste with a weight) of 87:13 was obtained. The paste was applied to both sides of the carbon non-woven fabric subjected to water repellent treatment as described above, dried, and then heated at 400 ° C. for 30 minutes to form a carbon fine powder layer. At this time, a part of the carbon fine powder layer was embedded in the carbon nonwoven fabric. Thus, the produced carbon nonwoven fabric and the carbon fine powder layer were combined to make a gas diffusion layer 1.
[0032]
Using the screen printing method, the catalyst paste 2 was applied on the carbon fine powder layer to form the catalyst layer 2. The catalyst layer 2, the carbon fine powder layer, and the carbon non-woven fabric thus produced were combined to form an electrode. The amount of platinum contained in the electrode is 0.5 mg / cm ² The amount of perfluorocarbon sulfonic acid is 1.2 mg / cm ² It adjusted so that it might become. This electrode was used for both the anode and cathode electrodes.
Next, a pair of electrodes are provided on both sides of a hydrogen ion conductive polymer electrolyte membrane (Nafion 112 manufactured by DuPont, USA) 3 whose outer size is 5 mm larger than that of the aforementioned electrode, and the catalyst layer 2 is an electrolyte membrane. 3 was joined by hot press so as to be in contact with 3 to obtain MEA. The MEA 22 was sandwiched between carbon separators 4 having airtightness from both sides to form a unit cell. The thickness of the separator 4 was 4 mm.
[0033]
Two cells of the above unit cells were stacked to obtain a battery constituent unit. The O-ring for sealing the cooling part was not used.
As shown in FIG. 2, the separator of the battery unit has a separator 4a in which a cooling water channel 24 is arranged on one surface, a gas channel 6 is arranged on the other surface, and a gas channel 5 is arranged on one surface. A separator 4b having a gas flow path 6 disposed on the other surface and a separator 4c having the gas flow path 5 disposed on one surface and the cooling water flow path 24 disposed on the other surface. It was. Further, as shown in FIG. 3, the gas supply ports 11 and 13 and the exhaust ports 11 ′ and 13 ′ and the cooling water supply port 12 and the discharge port 12 ′ are formed on opposite sides.
The gas flow paths 5 and 6 and the cooling water flow path 24 are formed on the surface of the separator plate by cutting. For example, the gas flow path 5 of the present example was formed by cutting a groove having a width of 2 mm and a depth of 1 mm into the shape of the separator as shown in FIG.
In this way, 50 cells were stacked, and a laminated battery was prepared by sequentially arranging a metal current collector plate, an insulating plate made of an electrically insulating material, and an end plate at both ends. End plates are arranged on the top and bottom of the laminate, and the fastening structure of the embodiment described with reference to FIGS. In other words, the metal wire (linear member) 39 having a wire diameter of 1 mm, the end plates 31 and 32, and the auxiliary plate 34 give a fastening force. The spring constant of the leaf spring function of the auxiliary plate 34 is 500 kgf / mm, compressed by 0.8 mm and applied with a fastening pressure of 400 kgf per linear member, and the fastening pressure during assembly is 13 kgf / cm. ² It was. When the pressure distribution of the separator plate was examined using pressure sensitive paper, it was confirmed that the pressure distribution was uniform over the entire surface. According to the present embodiment, compared to a conventional method in which a rod is disposed outside the separator plate to apply a fastening force, the fastening force can be applied from the inside of the separator plate, so that the deformation of the end plate is drastically reduced. Therefore, the thickness of the end plate can be 5 mm or less.
[0034]
<< Embodiment 5 >>
FIGS. 11, 2 and 3 show the fastening structure of the fuel cell in the present embodiment.
End plates 31 and 32 are arranged above and below the cell stack 30. Although not shown in particular, the cell stack 30 and the end plates 31 and 32 having output terminals (not shown) are electrically insulated by an insulating means. The end plate 31, the battery stack 30 and the end plate 32 are fastened by a plurality of linear members 39. Other than using a plurality of linear members, it is the same as the above embodiment.
The linear member 39 is put in a shape surrounding the battery laminate 30 and the end plates 31 and 32, and after applying an appropriate tension to the linear member 39, the linear member 39 is fixed by the fixing member 33 and the screw 35. By applying an appropriate tension to the linear member 39 and then fastening it, the laminate 30 is fastened via the end plate, and a necessary surface pressure is applied to the seal portion and the electrode. A gas supply port for supplying gas to the electrode and a discharge port corresponding to the cooling water supply port are provided on the lower surface opposite to the side having the supply port.
[0035]
Next, an example in which this embodiment is embodied will be described below.
First, a method for manufacturing the MEA will be described. Carbon fine powder (VXC72 manufactured by Cabot, USA, primary particle size: 30 nm, specific surface area: 254 m ² / G) was loaded with 25% by weight of platinum particles having an average particle size of about 30 mm as an electrode catalyst. In a dispersion obtained by dispersing this catalyst powder in isopropanol, the formula (1):

(Wherein 5 ≦ x ≦ 13.5, y≈1000, m = 1, n = 2)
[0036]
A dispersion obtained by dispersing the perfluorocarbonsulfonic acid powder represented by the formula (2) in ethyl alcohol was mixed to obtain a catalyst paste.
On the other hand, the porous substrate of the electrode, that is, the carbon paper constituting the gas diffusion layer was subjected to water repellent treatment. A carbon non-woven fabric having a thickness of 360 μm (TGP-H-120 manufactured by Toray Industries, Inc.) was impregnated with an aqueous dispersion containing polytetrafluoroethylene (Neolon ND1 manufactured by Daikin Industries, Ltd.), and then dried. Water repellency was imparted by heating at 400 ° C. for 30 minutes.
Next, fine carbon powder (acetylene black HS-100 manufactured by Denki Kagaku Kogyo Co., Ltd., primary particle diameter: 53 nm, specific surface area: 37 m ² / G, DBP oil absorption: 200 cc / 100 g) is dispersed in a polytetrafluoroethylene-containing aqueous dispersion (Nephron ND1 manufactured by Daikin Industries, Ltd.), and the mixing ratio of carbon fine powder and polytetrafluoroethylene ( A paste with a weight) of 87:13 was obtained. The paste was applied to both sides of the carbon non-woven fabric subjected to water repellent treatment as described above, dried, and then heated at 400 ° C. for 30 minutes to form a carbon fine powder layer. At this time, a part of the carbon fine powder layer was embedded in the carbon nonwoven fabric. Thus, the produced carbon nonwoven fabric and the carbon fine powder layer were combined to make a gas diffusion layer 1.
[0037]
Using the screen printing method, the catalyst paste 2 was applied on the carbon fine powder layer to form the catalyst layer 2. The catalyst layer 2, the carbon fine powder layer, and the carbon non-woven fabric thus produced were combined to form an electrode. The amount of platinum contained in the electrode is 0.5 mg / cm ² The amount of perfluorocarbon sulfonic acid is 1.2 mg / cm ² It adjusted so that it might become. This electrode was used for both the anode and cathode electrodes.
Next, a pair of electrodes are provided on both sides of a hydrogen ion conductive polymer electrolyte membrane (Nafion 112 manufactured by DuPont, USA) 3 whose outer size is 5 mm larger than that of the aforementioned electrode, and the catalyst layer 2 is an electrolyte membrane. 3 was joined by hot press so as to be in contact with 3 to obtain MEA. The MEA 22 was sandwiched between carbon separator plates 4 having airtightness from both sides to form a unit cell. The thickness of the separator plate 4 was 4 mm.
[0038]
Two cells of the above unit cells were stacked to obtain a battery constituent unit. The O-ring for sealing the cooling part was not used.
As shown in FIG. 2, the separator of the battery unit has a separator 4a in which a cooling water channel 24 is arranged on one surface, a gas channel 6 is arranged on the other surface, and a gas channel 5 is arranged on one surface. A separator 4b having a gas flow path 6 disposed on the other surface and a separator 4c having the gas flow path 5 disposed on one surface and the cooling water flow path 24 disposed on the other surface. It was. Further, as shown in FIG. 3, the gas supply ports 11 and 13 and the exhaust ports 11 ′ and 13 ′ and the cooling water supply port 12 and the discharge port 12 ′ are formed on opposite sides.
The gas flow paths 5 and 6 and the cooling water flow path 24 are formed on the surface of the separator by cutting. For example, the gas flow path 5 of the present embodiment is formed by cutting a groove having a width of 2 mm and a depth of 1 mm into the shape of the separator as shown in FIG.
Thus, 50 battery structural units were laminated, and a laminated battery was produced by sequentially arranging a metal current collector plate, an insulating plate made of an electrically insulating material, and an end plate at both ends.
End plates are arranged on the top and bottom of the laminated body to form the fastening structure of the embodiment described with reference to FIGS. In other words, the structure is such that three metal wires (linear members) 39 having a wire diameter of 1 mm and end plates 31 and 32 give a fastening force. Each of the three linear members 39 is given a tension of 575 kgf, and the fastening pressure during assembly is 13 kgf / cm. ² It was. When the pressure distribution of the separator plate was examined using pressure sensitive paper, it was confirmed that the pressure distribution was uniform over the entire surface. According to the present embodiment, compared to a conventional method in which a rod is disposed outside the separator plate to apply a fastening force, the fastening force can be applied from the inside of the separator plate, so that the deformation of the end plate is drastically reduced. Therefore, the thickness of the end plate can be 5 mm or less. Although three linear members are used here, the present invention is not particularly limited to this.
[0039]
【The invention's effect】
According to the present invention, it is possible to realize a fastening mechanism with a small and simple configuration, and to simplify the assembly process and reduce variations in surface pressure in the stacked battery surface by fastening with a linear member.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of a polymer electrolyte fuel cell according to an embodiment of the present invention.
FIG. 2 is a schematic longitudinal sectional view showing a main part of the fuel cell shown in FIG.
FIG. 3 is a diagram showing the positions of gas and cooling water supply / discharge ports in the fuel cell shown in FIG. 1;
FIG. 4 is a schematic partial sectional view showing a sealing method in a conventional polymer electrolyte fuel cell.
FIG. 5 is a schematic partial sectional view showing another sealing method in a conventional polymer electrolyte fuel cell.
FIG. 6 is a schematic partial sectional view showing still another sealing method in a conventional polymer electrolyte fuel cell.
FIG. 7 is a schematic perspective view of a battery unit in an internal manifold type polymer electrolyte fuel cell.
FIG. 8 is a schematic perspective view of a polymer electrolyte fuel cell according to another embodiment of the present invention.
FIG. 9 is a schematic perspective view of a polymer electrolyte fuel cell according to still another embodiment of the present invention.
FIG. 10 is a schematic perspective view of a polymer electrolyte fuel cell according to still another embodiment of the present invention.
FIG. 11 is a schematic perspective view of a polymer electrolyte fuel cell according to still another embodiment of the present invention.
[Explanation of symbols]
1 Diffusion layer
2 Catalytic reaction layer
3 Polymer electrolyte membrane
4 Separator
5, 6 Gas flow path
11, 13 Gas supply port
11 ', 13' gas outlet
12 Cooling water supply port
12 'Cooling water outlet
16 Gasket
17 Sealing material
18 O-ring
19 Gasket
21 resin
22 MEA
23 electrodes
24 Cooling water flow path
25 Seal part
30 Laminate
31, 32 End plate
33 Fixing member
34 Auxiliary plate
35 screws
35 'Tightening member
38 Spring
39 Linear members
39 'elastic member

Claims (5)

A unit cell comprising a polymer electrolyte membrane and a pair of electrodes having a catalytic reaction layer sandwiching the polymer electrolyte membrane, a means for supplying and distributing fuel gas to one of the electrodes, and an oxidant gas to the other of the electrodes A polymer electrolyte fuel cell comprising a laminate in which a plurality of layers are stacked via a conductive separator having a distribution means,
A first end plate at one end of the laminate and a second end plate at the other end;
A polymer characterized in that the laminate is fastened by a linear member spirally wound around an outer surface of an assembly including the laminate, the first end plate, and the second end plate. Electrolytic fuel cell. A unit cell comprising a polymer electrolyte membrane and a pair of electrodes having a catalytic reaction layer sandwiching the polymer electrolyte membrane, a means for supplying and distributing fuel gas to one of the electrodes, and an oxidant gas to the other of the electrodes A polymer electrolyte fuel cell comprising a laminate in which a plurality of layers are stacked via a conductive separator having a distribution means,
A first end plate at one end of the laminate and a second end plate at the other end;
An elastic member that compresses the laminated body in the laminating direction and an auxiliary plate that presses the elastic member in the laminating direction are disposed on at least one of the first end plate and the second end plate,
The laminated body is fastened by a linear member spirally wound around the outer surface of the assembly including the laminated body, the first end plate, the second end plate, the elastic member, and the auxiliary plate. A polymer electrolyte fuel cell characterized by comprising:   3. The polymer electrolyte fuel cell according to claim 1, wherein an end portion of the linear member is fixed via an elastic member.   3. The polymer electrolyte fuel cell according to claim 2, wherein the auxiliary plate is made of a metal plate having elasticity and also serves as the elastic member.   The polymer electrolyte fuel cell according to any one of claims 1 to 4, wherein the laminate is fastened by a plurality of linear members.

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