JP4061668B2 - Lithium ion non-aqueous electrolyte secondary battery - Google Patents

Description

【００４１】
表１の比較から、本発明に記載する保護層を担持した正極と負極の材料の構成に従った二次電池が、正極にコバルトニッケル酸化物系活物質用いた二次電池に比較して、電池性能の寿命と安全性能の点で優れていることがわかる。
【００４２】
【発明の効果】
本発明によれば、正極活物質の組成が他元素ドープ型リチウムニッケルコバルト複合酸化物、負極活物質が非晶質構造からなる錫酸化物を主体とする複合酸化物とすることにより、二次電池の放電容量を高め、コスト面でも優れたリチウムイオン非水電解質二次電池を提供することができ、さらに、活物質合剤層上に保護層が塗設された正極もしくは負極からなる非水電解質二次電池を用いることにより、正極に従来のリチウムニッケルコバルト酸化物系活物質を正極に用いた二次電池に比べてサイクル性能と安全性能に優れたリチウムイオン二次電池を提供することができる。
【図面の簡単な説明】
【図１】実施例に使用したシリンダー型電池の断面図を示す。
【符号の説明】
８ 正極シート
９ 負極シート
10 セパレーター
11 円筒型電池缶
12 正極端子を兼ねる電池蓋
13 ガスケット
14 安全弁[0001]
[Industrial application fields]
The present invention relates to a lithium ion non-aqueous electrolyte secondary battery having a high capacity.
[0002]
[Prior art]
Currently, general-purpose lithium-ion secondary batteries use various carbonaceous materials as materials for reversibly intercalating lithium in an ionic state for the negative electrode, and reversible insertion and release of lithium ions are also possible for the positive electrode. The lithium-containing metal composite oxide is used as a so-called rocking chair type lithium ion secondary battery in which these lithium storage / release materials are combined. As the positive electrode active material, LiCoO₂LiCo_1-xNi_xO₂LiNiO₂, LiMn₂O_FourAre widely used, and among these, LiCoO disclosed in JP-A-55-136131 is particularly preferred.₂Is 3.5 Vvs. This is advantageous in that it provides a charge / discharge potential higher than that of Li and has a high capacity. In addition, LiMn is advantageous because it has a large supply amount and low cost compared to the Co type.₂O_FourJapanese Patent Application Laid-Open Nos. 3-147276 and 4-123769 have proposed secondary batteries using as a positive electrode material.
Examples of the carbonaceous material used as the negative electrode active material include graphitic carbon material, pitch coke, fibrous carbon, and high-capacity soft carbon fired at a low temperature. The carbon material usually has a bulk density of 2.20. Since it is relatively small as described below, it is difficult to design a battery with a high effective capacity when used at a lithium insertion capacity (372 mAh / g) up to the stoichiometric limit. Therefore, as a negative electrode active material capable of inserting lithium having a high capacity density exceeding the carbonaceous material, JP-A-6-60867, 7-220721, 7-122274, 7-288123, and International Patent Publication (PCT) WO 96- 33519 discloses an amorphous active material mainly composed of a metal oxide.
These amorphous oxide negative electrodes can provide the battery with the highest energy density when combined with a cobalt oxide positive electrode having a high potential and capacity, while the manganese oxide positive electrode When combined, the energy density is reduced, but a battery with high cost efficiency can be provided. However, in order to provide a secondary battery that is superior in terms of synthetic raw material cost while maintaining the high capacity that is a feature of the amorphous oxide-based negative electrode material, it is advantageous in terms of both capacity and cost efficiency. It is important to use the positive electrode.
[0003]
[Problems to be solved by the invention]
However, LiNiO, which is the basic composition of nickel oxide positive electrode₂The discharge average voltage is LiCoO₂The cycle life of charge / discharge is generally poor. Since the average voltage is low, depending on the conditions of the operating voltage range of the secondary battery discharge and the discharge end voltage, LiNiO₂However, the capacity of the low voltage part cannot be effectively exhibited, which leads to an increase in battery capacity.
The object of the present invention is to solve the above-mentioned problems, and to increase the discharge capacity of a secondary battery using an oxide-amorphous negative electrode and a nickel oxide-based positive electrode. An electrolyte secondary battery is provided.
[0004]
[Means for Solving the Problems]
  The above-described problems of the present invention include a positive electrode using a lithium-containing metal composite oxide as an active material,Contains tin oxide as the main componentIn a secondary battery composed of a negative electrode using a metal composite oxide having an amorphous structure as an active material and a non-aqueous electrolyte, the positive electrode active material is Li_xNi_1-yCo_yzM_zO_2-aX_b(M is the periodTemperFrom Group 13 and Group 14 elements, Mn, Fe, Ti, Zr, Nd, La, Cu, V, Sm, W, Zn, Y, Mg, Sr, Ca, Ba, Cs, Na, P One or more selected elements, X is a halogen element, 0.2 <x ≦ 1.2, 0 <y ≦ 0.5, z <y, 0 <z <0.5, 0.01 ≦ a It has been solved by using a lithium ion non-aqueous electrolyte secondary battery characterized by being a nickel-containing lithium composite oxide having a composition of ≦ 0.5, 0.01 ≦ b ≦ 2a).
[0005]
The lithium ion non-aqueous electrolyte secondary battery of the present invention has a basic configuration consisting of a positive electrode active material, a negative electrode active material, and a non-aqueous electrolyte containing a lithium salt, and has a higher capacity than a conventional lithium battery using a carbon material negative electrode. It is characterized by being. The first element responsible for high capacity is a negative electrode active material, and the negative electrode active material of the present invention is preferably a metal complex oxide having an amorphous structure mainly containing tin oxide, and this negative electrode active material is a battery. Or lithium ions are electrochemically inserted (intercalated) into the metal composite oxide corresponding to the active material precursor in the battery. The second element responsible for high capacity is a lithium nickel composite oxide used as a positive electrode active material. The positive electrode active material of the present invention has a layered structure of LiNiO₂Is a structure in which other elements for improving performance are solid-solubilized, and the positive electrode active material is synthesized as a lithium compound outside the battery.
[0006]
  The positive electrode active material of the present invention is Li_xNi_1-yCo_yzM_zO_2-aX_bThe lithium composite oxide containing nickel and cobalt represented by the composition: Where M is LiNiO₂Is a metal or metalloid element that substitutes a part of Ni or Li in the skeleton structure of LiNiO.₂In the charge / discharge performance of the positive electrode, this is an element that contributes to the improvement of battery performance such as an increase in discharge average voltage and an improvement in cycle life. M is the periodTemperFrom Group 13 and Group 14 elements, Mn, Fe, Ti, Zr, Nd, La, Cu, V, Sm, W, Zn, Y, Mg, Sr, Ca, Ba, Cs, Na, P One or more selected elements, X is a halogen element, and the amount of these elements in the composition is 0.2 <x ≦ 1.2, 0 <y ≦ 0.5, z <y, 0 <z <. The ranges are 0.5, 0.01 ≦ a ≦ 0.5, 0.01 ≦ b ≦ 2a. Among these, one of the preferable compositions of the positive electrode active material is a composition in which fluorine is substituted as X, and Li_xNi_1-yCo_yzM_zO_2-aF_b(M is the periodTemperGroup 13 and Group 14 elements, one or more elements selected from transition metal elements other than Ni and Co, 0.2 <x ≦ 1.2, 0 <y ≦ 0.5, z <y , 0 <z <0.5, 0.01 ≦ a ≦ 0.5, 0.01 ≦ b ≦ 2a). As M in the composition of the positive electrode active material, one or more elements selected from Mn, Fe, Ti, B, Al, Sn, Si, Ga, and Mg are preferably used, and a preferable content of M is 0. .01 ≦ z ≦ 0.5. Particularly preferable as M is one or more elements selected from Mn, B, Al, and Si, and a preferable content at this time is in a range of 0.01 ≦ z ≦ 0.3.
[0007]
The synthesis of the lithium nickel composite oxide of the present invention is typified by a lithium compound that is a lithium material, a nickel compound that is a nickel material, and further a Co compound, and Mn, B, Al, Sn, Si, Mg, Fe, Ti, and the like. A compound containing other element M is mixed, and the raw material powder is baked in a high temperature dry state, or by a chemical reaction in a solution state typified by a solugel method.
Lithium raw materials include LiOH and Li₂CO_Three, Li₂O, LiNO_Three, Li₂SO_Four, LiHCO_Three, Li (CH_ThreeCOO), alkyl lithium and the like are used, and Ni raw materials include NiO and NiCO._Three, Ni (NO_Three)₂Ni powder, NiCl₂, NiSO_Four, Ni_Three(PO_Four)₂, Li (CH_ThreeCOO)₂, Ni (OH)₂NiOOH, Ni alkoxide, etc. are useful. Co as a cobalt raw material₂O_Three, Co_ThreeO_Four, CoCO_Three, Co (NO_Three)₂, CoCl₂As a raw material for other elements M, MnCO_Three, MnO₂, Mn (NO)_Three, B₂O_Three, B (OH)_Three, Al₂O_Three, Al (NO_Three)_Three, Al (OH)_Three, SnO₂, SnO, SnCl₂, Sn alkoxide, SiO₂, SiO, alkoxysilane, Mg (OH)₂, MgCO_Three, MgCl₂, Fe₂O_Three, FeCl_Three, FeOOH, Fe (NO_Three)_Three, TiO₂, GeO₂, ZrO₂, Nd₂O_Three, La₂O_Three, BaO, SrCO_Three, La₂O_Three, Zn (NO_Three)₂, WO_Three, Ga (NO_Three)₂, CuO, V₂O_Five, Sm₂O_Three, Y₂O_Three, AlF_Three, BaF₂, LiF, LaF_Three, SnF₂, Li_ThreePO_Four, AlPO_Four, Cs₂CO_Three, Ca (OH)₂, Na₂CO_ThreeEtc. can be used. These raw materials may be mixed in the form of a solid powder, or a plurality of raw materials may be dissolved in a solvent to form a mixed solution, which may be dried and solidified or in the form of a slurry.
[0008]
In the case of synthesizing by firing, the above raw material powder or slurry mixture is preferably used at a temperature of 400 ° C. to 1000 ° C., preferably 600 ° C. to 900 ° C. in the presence of oxygen or an oxygen partial pressure of 0.2 atm or higher. The synthesis is carried out by reacting for 4 to 48 hours in an atmosphere having an oxygen partial pressure of 0.5 or more. Firing may be performed a plurality of times under the same conditions or different conditions as necessary. The raw material mixture may be previously filled in a pellet and molded. The firing method is, for example, the powder mixing method described in JP-A-62-264560, JP-A-2-40861, JP-A-6-267538, and JP-A-6-231767, JP-A-4-237793, JP-A-5-325966, and JP-A-6-208334. The solution mixing method described in JP-A-62-211565, the synthesis method by coprecipitation described in JP-A-62-211565, the method of quenching the fired product described in JP-A-5-198301 and JP-A-5-205741, JP-A-5-283076, A method of firing by pellet molding described in JP-A-6-310145, a method of firing in a molten state using LiOH hydrate described in JP-A-5-325969, and synthesis under oxygen partial pressure control described in JP-A-6-60887 Method, a fluorine doping method described in JP-A-6-243871, and active materials having different internal and surface compositions of particles described in JP-A-8-138670. And a method in which it is effective.
[0009]
The content of elements other than elements (Li, Ni, Co and other elements M) in the composition formula that the positive electrode active material contains as impurities is, for example, 0.01% or less for Fe and 0.01% or less for Cu as weight concentrations, Ca, Mg, Na and sulfate radicals (SO_Four) Are preferably 0.05% or less. The water content in the active material is preferably 0.1% or less.
[0010]
The preferable particle diameter of the positive electrode active material is that the particle diameter of the secondary particles is 1 to 30 μm, the particle diameter of the primary particles is 0.1 to 1 μm, and more preferably the particle diameter of the secondary particles is 3 to 15 μm. Has a particle size of 0.1 to 0.5 μm. Here, the secondary particle means a particle formed by agglomeration of fine primary particles, and corresponds to a particle size usually measured by a laser scattering particle size distribution measurement or the like, and corresponds to a normally defined particle size.
As for the shape of the particles, the secondary particles are particularly preferably spherical. Moreover, it is preferable that the surface of the secondary particle is porous.
[0011]
The specific surface area of the positive electrode active material is 0.1 to 10 m as measured by the BET method.²/ G is preferred, 0.3-3 m²/ G is more preferable. Moreover, the tap density of the positive electrode active material is preferably in the range of 2.3 to 2.9, and more preferably in the range of 2.5 to 2.8.
[0012]
  The positive electrode active material particles used in the present invention may be crystalline or may contain an amorphous structure inside or on the surface, but are preferably crystalline. When crystalline positive electrode active material particles are used, the a-axis lattice constant measured by X-ray diffraction is 2.81 to 2.91.ÅIn the rangeThe c-axis lattice constant is13.7 to 14.4ÅIt is preferable that it is the range of these. Further, the ratio of the diffraction peak intensity on the (104) plane to the peak intensity on the (003) plane is in the range of 0.1 to 0.9, and preferably in the range of 0.3 to 0.8. In addition, it is preferable that no peak of impurities derived from firing raw materials or side reactions such as lithium carbonate and nickel oxide is observed in the crystal diffraction spectrum.
[0013]
  Although the example of the preferable composition of a positive electrode active material is shown below, the scope of the present invention is not limited to these.
  LiNi_0.7Co_0.26B_0.04O_1.9F_0.2
  LiNi_0.7Co_0.26Al_0.04O_1.9F_0.2
  Li_1.03Ni_0.67Co_0.26Al_0.04O_1.9F_0.2
  LiNi _0.8 Co_0.10Mn_0.07B_0.03O _{1 .95}F_0.05
  Li_1.03Ni_0.8Co_0.10Mn_0.07B_0.03O _{1 .95}F_0.05
  Li_1.03Ni_0.77Co_0.15B_0.03Al_0.02O _{1 .9}F_0.19
[0014]
  The secondary battery of the present invention is characterized by using a composite oxide containing an amorphous structure as a negative electrode material. Since the amorphous composite oxide negative electrode is characterized by high capacity lithium occlusion, the rocking chair type secondary object which is the object of the present invention can be obtained by combining with the above-mentioned nickel oxide positive electrode having a high capacity in balance. The capacity of the battery can be increased efficiently. The active material of the negative electrode is preferably composed mainly of tin oxide and periodicTemperIt is a material containing one or more selected from Table Group 1, Group 2, Group 13, Group 14, Group 15, Transition Metal, and Halogen Elements. More specifically, the negative electrode active material is an amorphous complex oxide containing tin as a main component, and lithium ions are electrochemically inserted into the precursor of the negative electrode active material represented by the following general formula. can get.
  Sn_xM¹ _1-xM² _yO_zWhere M¹Is one or more selected from Mn, Fe, Pb, Ge, M²Is Al, B, P, Si, periodTemper2 or more elements selected from Table Group 1, Group 2, Group 3, and halogen elements are shown, and 0 <x ≦ 1, 0.1 ≦ y ≦ 3, 1 ≦ z ≦ 8. A more preferred composition according to the above structural formula is described as M¹Is an element selected from Pb and Ge, and M²Is B, P, Si, periodTemperTwo or more elements selected from Table Group 1 and Group 2, M²Is particularly preferably an element other than Al.
[0015]
The insertion of lithium ions into the active material precursor is carried out by cathodic polarization of the negative electrode in the presence of lithium ions in the battery and electrochemical insertion of the lithium ions into the structure.
The composite oxide as the precursor of the present invention is characterized in that the structure contains an amorphous structure or is amorphous. The complex oxide of the present invention includes an amorphous structure, specifically, a diffraction scattering band having a broad apex with a weak intensity from 20 ° to 40 ° as a 2θ value by an X-ray diffraction method using CuKα rays. In this broad scattering band, a crystalline diffraction line may be included. This crystalline diffraction line is a reflection of a slightly ordered structure in the amorphous structure. More preferably, when a crystalline diffraction line is observed at a 2θ value of 40 ° or more and 70 ° or less, the strongest intensity of the crystalline diffraction lines is observed at a 2θ value of 20 ° or more and 40 ° or less. The intensity of the diffraction line at the apex of the broad scattering band is preferably 500 times or less, more preferably 100 times or less, particularly preferably 5 times or less, and most preferably no crystalline diffraction line. .
[0016]
The negative electrode active material precursor is prepared by mixing a tin compound, which is a tin raw material, and a powder of a compound containing an element other than tin, and melting the mixture at a high temperature of 800 ° C. to 1500 ° C., preferably 900 ° C. to 1200 ° C. for 4 hours to Synthesize by reacting for 48 hours. The synthesis atmosphere is preferably an inert gas atmosphere such as nitrogen or argon. Especially the oxygen partial pressure is 10^-1Or less, preferably 10^-2The reaction is preferably carried out under the following conditions.
The reaction may be quenched at a rate of 50 ° C. to 500 ° C./min to promote amorphization. Conversely, slow cooling can be performed for the purpose of increasing the density of the amorphous structure and increasing the strength.
The glassy negative electrode material obtained by these methods is pulverized to obtain a particle size distribution and used as negative electrode particles. A preferable range of the negative electrode particles is 0.5 to 20 μm as an average particle diameter, and more preferably 1 to 10 μm.
In addition to the melting method, a synthesis method using a solution reaction, for example, a synthesis by a sol-gel method can be used. The range of the preferable average particle diameter of the particle | grains synthesize | combined by a sol-gel method is 0.1-10 micrometers as a particle diameter of a secondary particle, More preferably, it is 0.2-5 micrometers.
[0017]
Below, the preferable example of the negative electrode active material precursor used by this invention is shown.
SnSi_0.8P_0.2O_3.1
SnSi_0.5B_0.2P_0.2O_1.85
SnSi_0.8B_0.2O_2.9
SnSi_0.8Al_0.2O_2.9
SnSi_0.6Al_0.1B_0.2O_1.65
SnSi_0.3Al_0.1P_0.6O_2.25
SnSi_0.4B_0.2P_0.4O_2.1
SnSi_0.6Al_0.1B_0.5O_2.1
SnB_0.5P_0.5O_Three
SnK_0.2PO_3.6
SnRb_0.2P_0.8O_3.2
SnBa_0.1P_1.45O_4.5
SnLa_0.1P_0.9O_3.4
SnNa_0.1B_0.45O_1.75
SnLi_0.2B_0.5P_0.5O_3.1
SnCs_0.1B_0.4P_0.4O_2.65
SnBa_0.1B_0.4P_0.4O_2.7
SnCa_0.1Al_0.15B_0.45P_0.55O_3.9
SnY_0.1B_0.6P_0.6O_3.55
SnRb_0.2B_0.3P_0.4O_2.55
SnCs_0.2B_0.3P_0.4O_2.55
SnCs_0.1B_0.4P_0.4O_2.65
SnK_0.1Cs_0.1B_0.4P_0.4O_2.7
SnBa_0.1Cs_0.1B_0.4P_0.4O_2.75
SnMg_0.1K_0.1B_0.4P_0.4O_2.75
SnCa_0.1K_0.1B_0.4P_0.5O_Three
SnBa_0.1K_0.1Al_0.1B_0.3P_0.4O_2.75
SnMg_0.1Cs_0.1Al_0.1B_0.3P_0.4O_2.75
SnCa_0.1K_0.1Al_0.1B_0.3P_0.4O_2.75
SnMg_0.1Rb_0.1Al_0.1B_0.3P_0.4O_2.75
SnCa_0.1B_0.2P_0.2F_0.2O_2.6
SnMg_0.1Cs_0.1B_0.4P_0.4F_0.2O_3.3
Sn_0.5Mn_0.5Mg_0.1B_0.9O_2.45
Sn_0.5Mn_0.5Ca_0.1P_0.9O_3.35
Sn_0.5Ge_0.5Mg_0.1P_0.9O_3.35
Sn_0.5Fe_0.5Ba_0.1P_0.9O_3.35
Sn_0.8Fe_0.2Ca_0.1P_0.9O_3.35
Sn_0.3Fe_0.7Ba_0.1P_0.9O_3.35
Sn_0.9Mn_0.1Mg_0.1P_0.9O_3.35
Sn_0.2Mn_0.8Mg_0.1P_0.9O_3.35
Sn_0.7Pb_0.3Ca_0.1P_0.9O_3.35
Sn_0.2Ge_0.8Ba_0.1P_0.9O_3.35
Sn_1.0Al_0.1B_0.5P_0.5O_3.15
Sn_1.0Cs_0.1Al_0.4B_0.5P_0.5O_3.65
Sn_1.0Cs_0.1B_0.5P_0.5O_3.05
Sn_1.0Cs_0.1Ge_0.05B_0.5P_0.5O_3.15
Sn_1.0Cs_0.1Ge_0.05Al_0.3B_0.5P_0.5O_3.60
[0018]
Examples of the negative electrode active material that can be used in the secondary battery of the present invention together with the negative electrode active material made from the above precursor include lithium metal, the above lithium alloy, and the like, and a carbonaceous compound that can occlude and release lithium ions or lithium metal. (For example, JP-A-58-209,864, 61-214,417, 62-88,269, 62-216,170, 63-13,282, 63-24,555, 63- 121,247, 63-121,257, 63-155,568, 63-276,873, 63-314,821, JP-A-1-204,361, 1-221,859, 1- 274, 360). The combined use of the lithium metal and lithium alloy is for inserting lithium ions in the battery, and does not utilize a dissolution and precipitation reaction such as lithium metal as the battery reaction.
[0019]
  In the secondary battery of the present invention, either one surface of the active material mixture layer of the positive electrode and the negative electrode is covered with a protective layer coated continuously with the mixture layerIs preferred.This protective layer is provided for the purpose of ensuring the safety of the secondary battery. Although the secondary battery of the present invention using a nickel-based active material has a high capacity, the property that nickel oxide is chemically unstable at high temperatures is the safety of high-capacity batteries, especially under overcharge. It is generally pointed out that it adversely affects sex. The protective layer used in the present invention is applied for the purpose of ensuring the safety of the high-capacity battery from such a viewpoint. The protective layer of the present invention is installed at the interface between the active material mixture layer containing an active material, a conductive material, a binder material, and the like and a non-aqueous electrolyte, and substantially includes an electrically insulating inorganic substance as a main component. It is characterized by being installed as a protective layer having no conductivity. The protective layer is continuously applied as a surface layer of the active material mixture layer with the mixture layer, and the mixture layer and the protective layer are continuous. Therefore, at least one of the positive electrode and the negative electrode is composed of at least two layers including the active material mixture layer and the surface protective layer. The protective layer is different from a separator (usually a film-like porous polymer resin) inserted between the positive electrode and the negative electrode, and is provided separately. The protective layer is preferably a coating mainly composed of electrically insulating inorganic compound or ceramic particles. Further, organic particles such as polymer latex may also be included. Preferable main components constituting the protective layer include inorganic oxides such as alumina, boron oxide, calcium oxide, titanium oxide, zirconium oxide, barium oxide, and silicon oxide. Of these, preferred main components in terms of electrochemical stability and coating suitability are alumina, silicon oxide, titanium oxide, and zirconium oxide. The preferable particle diameter of these oxide particles is in the range of 0.01 to 10 μm as the average particle diameter. Usually, a thickener such as CMC, a polymer binder typified by a Teflon resin, a binder described later, and the like are added to these main components as a coating aid. The thickness of the protective layer is in the range of 2 to 50 μm, preferably 20 μm or less, more preferably 10 μm or less.
[0020]
The protective layer may be coated on the positive electrode mixture layer or may be coated on the negative electrode mixture layer. Moreover, you may coat on both. The protective layer is applied to the current collector sheet after these mixtures are dried and then sequentially applied to the surface thereof, or is applied while taking a multilayer structure simultaneously with the mixture layer.
[0021]
A conductive agent, a binder, a filler, or the like can be added to the electrode mixture. The conductive agent may be anything as long as it is an electron conductive material that does not cause a chemical change in the constructed battery. Usually, natural graphite (scale-like graphite, scale-like graphite, earth-like graphite, etc.), artificial graphite, carbon black, acetylene black, ketjen black, carbon fiber and metal (copper, nickel, aluminum, silver (JP-A-63-148)) , 554) etc.) Conductive materials such as powder, metal fibers or polyphenylene derivatives (Japanese Patent Laid-Open No. 59-20,971) can be included as one kind or a mixture thereof. The combined use of graphite and acetylene black is particularly preferred. The addition amount is not particularly limited, but is preferably 1 to 50% by weight, particularly preferably 2 to 30% by weight. In the case of carbon or graphite, 2 to 15% by weight is particularly preferable.
[0022]
The binder is usually starch, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, regenerated cellulose, diacetyl cellulose, polyvinyl chloride, polyvinyl pyrrolidone, tetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, ethylene-propylene-di. Enter polymers (EPDM), sulfonated EPDM, styrene butadiene rubber, polybutadiene, fluororubber, polyethylene oxide and other polysaccharides, thermoplastic resins, rubber elastic polymers and the like are used as one kind or a mixture thereof. The addition amount of the binder is preferably 2 to 30% by weight. Any filler can be used as long as it is a fibrous material that does not cause a chemical change in the constructed battery. Usually, olefin polymers such as polypropylene and polyethylene, fibers such as glass and carbon are used. Although the addition amount of a filler is not specifically limited, 0 to 30 weight% is preferable.
[0023]
  Non-aqueous electrolytes used for the production of secondary batteries include propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, γ-butyrolactone, 1,2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, dimethylsulfate. Foxoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate, methyl acetate, phosphoric acid triester (JP 60-23973), trimethoxymethane (JP 61- 4,170), dioxolane derivatives (Japanese Patent Laid-Open Nos. 62-15771, 62-22,372, 62-108,474), sulfolane (Japanese Patent Laid-Open No. 62-31,959), 3-methyl-2- Oxazolidinone ( No. 62-44,961), propylene carbonate derivatives (JP-A 62-290,069, 62-290,071), tetrahydrofuran derivatives (JP-A 63-32,872), diethyl ether (JP-A 63) -62,166), 1,3-propane sultone (Japanese Patent Laid-Open No. Sho 63-102,173) and a mixture of at least one aprotic organic solvent and a lithium salt soluble in the solvent, such as LiClO_Four, LiBF₆, LiPF₆, LiCF_ThreeSO_Three, LiCF_ThreeCO₂, LiAsF₆, LiSbF₆, LiB_TenCl_Ten(JP-A 57-74,974), lower aliphatic lithium carboxylate (JP-A 60-41,773), LiAlCl_FourOne or more salts such as LiCl, LiBr, LiI (JP 60-247265), lithium chloroborane (JP 61-165,957), lithium tetraphenylborate (JP 61-214,376) It is composed of Among them, LiCF is added to a mixed solution of propylene carbonate or ethylene carbonate and 1,2-dimethoxyethane and / or diethyl carbonate._ThreeSO_Three, LiClO_Four, LiBF_FourAnd / or LiPF₆An electrolyte containing is preferred.The amount of these electrolytes added to the battery is not particularly limited, but a necessary amount can be used depending on the amount of the positive electrode active material and the negative electrode active material and the size of the battery. The volume ratio of the solvent is not particularly limited, but in the case of a mixed liquid of propylene carbonate or ethylene carbonate to 1,2-dimethoxyethane and / or diethyl carbonate, 0.4 / 0.6 to 0.6 / 0.4 ( The mixing ratio when both 1,2-dimethoxyethane and diethyl carbonate are used is preferably 0.4 / 0.6 to 0.6 / 04). The concentration of the supporting electrolyte is not particularly limited, but is preferably 0.2 to 3 mol per liter of the electrolytic solution. Among the above electrolyte solutions, the electrolyte solution composition of the present invention is particularly preferable in terms of the effect of improving the charge / discharge cycle life of the secondary battery, at least ethylene carbonate as a solvent, and at least LiPF.₆As a lithium salt, and another preferred composition is at least LiPF using at least ethylene carbonate and diethyl carbonate as a solvent.₆Is a composition containing lithium as a lithium salt, and another preferred composition is at least LiPF using both ethylene carbonate and dimethyl carbonate as a solvent.₆In the form of a lithium salt.
[0024]
In addition to the electrolytic solution, the following organic solid electrolyte can also be used. For example, a polyethylene oxide derivative or a polymer containing the derivative (Japanese Patent Laid-Open No. 63-135447), a polypropylene oxide derivative or a polymer containing the derivative, a polymer containing an ionic dissociation group (Japanese Patent Laid-Open Nos. 62-254,302 and 62-254, 303, 63-193, 954), a mixture of an ion-dissociable group-containing polymer and the above aprotic electrolyte (US Pat. Nos. 4,792,504, 4,830,939, JP-A-62-222,375, 62-22,376, 63-22,375, 63-22,776, JP-A-1-95,117), and phosphate polymer (JP-A-61-256,573) are effective. Furthermore, there is a method of adding polyacrylonitrile to the electrolytic solution (Japanese Patent Laid-Open No. 62-278,774). In addition, a method using an inorganic and organic solid electrolyte in combination (Japanese Patent Laid-Open No. 60-1,768) is also known.
[0025]
As a separator used for the secondary battery, an insulating thin film having a large ion permeability and a predetermined mechanical strength is used. Sheets and non-woven fabrics made from olefin polymers such as polypropylene, glass fibers or polyethylene are used because of their organic solvent resistance and hydrophobicity. A range useful for batteries is generally used as the pore diameter of the separator. For example, 0.01 to 10 μm is used. The thickness of the separator is generally used in the battery range. For example, 5 to 300 μm is used.
When a solid electrolyte such as a polymer is used as the electrolyte, the solid electrolyte may also serve as a separator.
[0026]
In order to improve discharge and charge / discharge characteristics, it is known to add the following compounds to the electrolyte. For example, pyridine (JP 49-108,525), triethyl phosphite (JP 47-4,376), triethanolamine (JP 52-72,425), cyclic ether (JP 57-57). 152, 684), ethylene diamine (JP 58-87,777), n-glyme (JP 58-87,778), hexaphosphoric triamide (JP 58-87,779), nitrobenzene derivatives (JP 58-214,281), sulfur (JP 59-8,280), quinoneimine dyes (JP 59-68,184), N-substituted oxazolidinones and N, N'-substituted imidazolidinones (JP No. 59-154,778), ethylene glycol dialkyl ether (JP 59-205,167), quaternary ammonium salt (JP 60-30,065) Polyethylene glycol (JP 60-41,773), pyrrole (JP 60-79,677), 2-methoxyethanol (JP 60-89,075), aluminum trichloride (JP 61-88) , 466), monomers of conductive polymer electrode active materials (JP 61-161,673), triethylenephosphonamide (JP 61-208,758), trialkylphosphine (JP 62-80,976). ), Morpholine (JP 62-80,977), aryl compounds having a carbonyl group (JP 62-86,673), hexamethylphosphoric triamide and 4-alkylmorpholine (JP 62-62). 217,575), bicyclic tertiary amines (JP 62-217,578), oils (JP 62-287,580), quaternary phosphoniu. Salt (JP-63-121,268), and a tertiary sulfonium salt (JP 63-121,269).
[0027]
In order to make the electrolyte nonflammable, a halogen-containing solvent such as carbon tetrachloride or ethylene trifluoride chloride can be contained in the electrolyte (Japanese Patent Laid-Open No. 48-36,632). In addition, carbon dioxide gas can be included in the electrolytic solution to make it suitable for high-temperature storage (Japanese Patent Laid-Open No. 59-134,567).
[0028]
The mixture of the positive electrode and the negative electrode may contain an electrolytic solution or a supporting salt. For example, a method is known in which the ion conductive polymer, nitromethane (Japanese Patent Laid-Open No. 48-36,633), and electrolytic solution (Japanese Patent Laid-Open No. 57-124,870) are included.
In addition, the surface of the positive electrode active material can be modified. For example, the surface of the metal oxide is treated with an esterifying agent (Japanese Patent Laid-Open No. 55-163,779) or a chelating agent (Japanese Patent Laid-Open No. 55-163,780), or a conductive polymer (Japanese Patent Laid-Open No. 58-163). 163, 188, 59-14, 274), and a method of modification by covering with a surface layer of polyethylene oxide or the like (JP-A-60-97,561). Similarly, the surface of the negative electrode active material can be modified. For example, an ion conductive polymer or a polyacetylene layer can be coated (Japanese Patent Laid-Open No. 58-111,276), or surface treatment can be performed with a Li salt (Japanese Patent Laid-Open No. 58-142,771).
[0029]
The current collector of the electrode active material may be anything as long as it is an electronic conductor that does not cause a chemical change in the constructed battery. For example, in addition to stainless steel, nickel, aluminum, titanium, calcined carbon, etc. as materials for the positive electrode, the surface of aluminum or stainless steel is treated with carbon, nickel, titanium, or silver. In addition to stainless steel, nickel, copper, titanium, aluminum, calcined carbon, etc., the surface of copper or stainless steel treated with carbon, nickel, titanium or silver), Al—Cd alloy, or the like is used. Oxidizing the surface of these materials is also used. As the shape, a film, a sheet, a net, a punched product, a lath body, a porous body, a foamed body, a molded body of a fiber group, and the like are used in addition to the foil. The thickness is not particularly limited, but a thickness of 5 to 100 μm is used.
[0030]
The battery shape can be applied to any of coins, buttons, sheets, cylinders, and corners. In coins and buttons, a mixture of a positive electrode active material and a negative electrode active material is used after being pressed into a pellet shape. In the sheet, cylinder, and corner, the positive electrode active material and the negative electrode active material mixture are applied onto a current collector, dried, dehydrated, and pressed. The coating thickness is determined by the size of the battery, and is preferably 10 to 500 μm in a compressed state after drying.
The use of the non-aqueous secondary battery of the present invention is not particularly limited. For example, when mounted on an electronic device, a color notebook computer, a monochrome notebook computer, a pen input personal computer pocket (palmtop) personal computer, a notebook word processor, a pocket word processor , Electronic book player, mobile phone, cordless phone, pager, handy terminal, mobile fax, mobile copy, mobile printer, headphones stereo video movie, LCD TV, handy cleaner, portable CD, mini desk, electric shaver, electronic translation Machine, car phone, transceiver, electric tool, electronic notebook, calculator, memory card, tape recorder, radio, backup power supply, memory card, etc. Others for consumer use include automobiles, electric vehicle motors, lighting equipment, toys, game equipment, road conditioners, irons, watches, strobes, cameras, medical equipment (pacemakers, hearing aids, shoulder grinders, etc.). Furthermore, it can be used for various military use and space use. It can also be combined with solar cells.
Hereinafter, the present invention will be described in more detail with reference to examples of battery production. However, the scope of the present invention is not limited to these examples as long as the gist of the invention is not exceeded.
[0031]
【Example】
[Synthesis example of negative electrode active material precursor, melting method]
SnO 67.4g, B₂O_Three  17.4g, Sn₂P₂O₇  102.8 g was mixed, sufficiently ground and mixed in an automatic mortar, then set in an alumina crucible and fired at 1000 ° C. for 10 hours in an argon gas atmosphere. After firing, it is rapidly cooled at a rate of 100 ° C./min, and a yellow transparent glassy negative electrode active material precursor SnB_0.5P_0.5O_Three(Compound A-1) was obtained. When X-ray diffraction of the active material was measured, it showed a broad diffraction band in the region of 2θ = 20-35 ° under the irradiation of Cu-α ray, but a sharp diffraction line attributed to the crystal structure was detected. Thus, the active material structure was found to be amorphous (amorphous).
In the same manner, the following negative electrode active material precursor was synthesized.
Sn_1.5K_0.2PO_3.5(Compound A-2)
Sn_1.0Cs_0.1Ge_0.05Al_0.1B_0.5P_0.5O_3.30(Compound A-3)
Both A-1 to A-3 were pulverized to an average particle size of 7 μm, and the specific surface area by the BET method was 0.7 to 1.2 m.²/ G.
[Synthesis example of negative electrode active material precursor, sol-gel method]
Sn_0.8Si_0.5B_0.3P_0.2Al_0.1O_3.70(Compound A-4) was synthesized by the following sol-gel method. 212 g of diethoxytin was dissolved in 100 g of DMF, and 34 g of phosphorous triethoxide, 51 g of triethoxyaluminum, 36 g of triethoxyboron, and 134 g of tetraethoxysilane were added thereto, and sulfuric acid was further added and mixed to obtain a first liquid. 4.25 g of sorbitan monooleate was dissolved in 1700 cc of toluene to make a second solution. While dripping the first liquid into the second liquid, the mixture was vigorously stirred at 10,000 rotations, and 45 g of triethylamine was added to the reaction liquid in 5 portions. Stirring was continued for 2 hours while maintaining the reaction solution at 40 ° C., and then maintained at 40 ° C. for 24 hours, after which the solvent toluene was removed under reduced pressure. The obtained solid was dried at 250 ° C. for 48 hours to obtain a white powder. Yield 95%.
The sol-gel particles are porous spherical particles having an average particle size of 0.1 μm and a BET specific surface area of 8 m.²/ G.
[0032]
[Example of preparation of positive electrode active material]
  LiNi₀. 8Co0.₁₆B0.₀₄O₂(Compound C-1) was synthesized by the following method. LiOH ・ H₂O, Ni (OH)₂, Co (OH)₂And B₂O_ThreeWere thoroughly mixed in a mortar under dry air at a stoichiometric ratio of 1: 0.8: 0.16: 0.02 and baked at 650 ° C. for 6 hours in an oxygen atmosphere. Firing was performed at 750 ° C. for 8 hours to synthesize Compound C-1 having the above composition. The obtained particles had a shape close to a sphere, and the average particle size of primary particles was 0.3 μm, and the average particle size of secondary particles was 7 μm. The specific surface area by BET method is 0.7m.²/ G. The peak ratio of (104) plane / (003) plane obtained by X-ray diffraction is 0.6, and the lattice constant of the a axis is 2.83.Å, C axisofThe lattice constant is 13.90.ÅMet. The active material gave a pH of 10.5 when 1 g was dispersed in 10 cc of pure water. In addition, the active material having the same composition is LiOH · H as a lithium raw material.₂LiNO instead of O_{twenty three}Or LiCO_ThreeNi (OH) as Ni raw material₂Instead of NiCO_ThreeCan also be synthesized. In addition, B₂O_ThreeInstead of Al (OH)_ThreeWas added at a stoichiometric ratio, followed by baking at 650 ° C. for 6 hours in an oxygen atmosphere, followed by baking at 800 ° C. for 12 hours to obtain LiNi0.₈Co0.₁₆Al0.₀₄O₂(Compound C-2) was synthesized. Moreover, according to the baking method of compound C-2, the raw material was suitably selected and the following positive electrode active material was synthesized. The composition of these active materials was tested by ICP.
LiNi_0.8Co_0.1Mn_0.1O₂(Compound C-3)
LiNi_0.8Co_0.1Mn_0.07B_0.03O₂(Compound C-4)
LiNi_0.8Co_0.15Sn_0.05O₂(Compound C-5)
LiNi_0.8Co_0.15Si_0.05O₂(Compound C-6)
LiNi_0.8Co_0.15Mg_0.05O₂(Compound C-7)
LiNi_0.8Co_0.15Fe_0.05O₂(Compound C-8)
LiNi_0.8Co_0.15Ti_0.05O₂(Compound C-9)
  Further, using the LiF as a fluorine raw material, firing was performed at 650 ° C. for 24 hours under an oxygen partial pressure of 0.5 atm to synthesize the following compounds.
LiNi_0.8Co_0.15B_0.05O_1.9F_0.1(Compound C-10)
LiNi_0.8Co_0.15Al_0.05O_1.9F_0.1(Compound C-11)
  The above (Compound C-1) to (Compound C-9) are reference examples.
[0033]
LiNi as a positive electrode active material for comparison_0.8Co_0.2O₂(Comparison 1) to Co_ThreeO_Four, Co₂O_ThreeAnd NiCO_ThreeAnd lithium carbonate were mixed at a stoichiometric ratio and synthesized by baking at 650 ° C. for 4 hours and further at 800 ° C. for 8 hours in an oxygen atmosphere.
[0034]
[Production example of electrode mixture sheet]
The positive electrode mixture is composed of 90% by weight of the positive electrode active material compound C-1, 6% by weight of acetylene black, and 3% by weight of an aqueous dispersion of polytetrafluoroethylene and 1% by weight of sodium polyacrylate as a binder. Water was added to the mixture and kneaded, and the resulting slurry was applied to both surfaces of an aluminum film having a thickness of 30 μm to produce a positive electrode sheet.
Next, a protective layer (average thickness 5 μm) made of a 1: 4 (weight ratio) mixture of scaly graphite and aluminum oxide (average particle size 2 μm) is applied to the surface of the active material mixture layer of the positive electrode sheet. Set up. As a result of drying and pressing the coated sheet, the coating amount of the dry film was 240 g / m.²The thickness of the coating film was approximately 95 μm.
For comparison, a positive electrode sheet without the protective layer was prepared.
[0035]
86% by weight of compound A-1 as a negative electrode active material precursor, 3% by weight of flake graphite, 6% by weight of acetylene black, 4% by weight of an aqueous dispersion of polytetrafluoroethylene and 1% by weight of carboxymethyl cellulose as a binder Water was added to the mixture and kneaded at 10,000 rpm for 10 minutes or more with a homogenizer to prepare a negative electrode mixture slurry. The obtained slurry was applied to both sides of a 18 μm thick copper film to prepare a negative electrode sheet. As a result of drying and pressing the coated sheet, the coating amount of the dry film was about 70 g / m.²The thickness of the coating film was about 30 μm.
Next, a protective layer (average thickness of 5 μm) made of a 1: 4 (weight ratio) mixture of scaly graphite and aluminum oxide (average particle size of 2 μm) was applied to the surface of the active material layer of the negative electrode sheet.
In the same manner, the protective layer is coated on the surface of the active material precursor layer prepared by applying A-2, A-3, and A-4 instead of compound A-1 as the negative electrode active material precursor. And the negative electrode sheet with the surface protective layer which coated various active material precursors was produced.
[0036]
[Production example of cylinder type battery]
The surfaces of both surfaces of the negative electrode sheet obtained by cutting a metal Li foil having a thickness of 35 μm into pieces having a width of 5 mm and a length of 37 mm and applying the negative electrode active material precursors A-1 to 4 in dry air having a dew point of −60 ° C. It was adhered on the protective layer using a pressure roller at regular intervals of 2 mm. The amount of Li attached to the negative electrode sheet was approximately 110 mg by weight. This lithium is used for electrolytically inserting lithium into the negative electrode active material precursor in the battery and converting the negative electrode active material precursor into an active material.
The positive electrode sheet was cut to a width of 35 mm, the negative electrode sheet was cut to a width of 37 mm, and aluminum and nickel lead plates were spot welded to the ends of the sheet, respectively, and then dried in dry air at a dew point of −40 ° C. Dehydrated and dried at 2 ° C. for 2 hours. As shown in the cross-sectional view of the battery in FIG. 1, a dehydrated and dried positive electrode sheet (8), a porous propylene film (Celgard 2400) (10) as a separator, a dehydrated and dried negative electrode sheet (9), and a separator ( These were laminated in the order of 10) and wound in a spiral shape with a winder. The wound body was stored in a nickel-plated iron-bottomed cylindrical battery can (11) (also serving as a negative electrode terminal). 1 mol / liter LiPF as electrolyte in this battery can₆(A 2: 2: 6 (volume ratio) mixture of ethylene carbonate, butylene carbonate, and dimethyl carbonate) was injected.
A battery lid (12) having a positive electrode terminal was caulked through a gasket (13) to produce a cylindrical battery having a diameter of 14 mm and a height of 50 mm. The positive electrode terminal (12) was connected to the positive electrode sheet (8) and the battery can (11) was previously connected to the negative electrode sheet (9) by a lead terminal. (14) is a safety valve.
[0037]
According to this method, C-1 to 11 as the positive electrode active material and A-1 to A-4 as the negative electrode active material were selected and combined to prepare various batteries.
[0038]
The battery produced as described above is a battery precursor in which the process of electrochemically inserting lithium on the coating sheet protective layer into the negative electrode active material precursor is not completed. Therefore, an operation for converting the battery precursor into a negative electrode active material by inserting lithium into the negative electrode active material precursor and making the battery precursor a chargeable / dischargeable secondary battery was performed as follows. The battery precursor was allowed to stand at room temperature for 12 hours, precharged for 1 hour under a constant current of 0.1 A, and then aged at 50 ° C. for 10 days. In this aging step, it was confirmed that Li supported on the negative electrode was dissolved and inserted into the negative electrode active material precursor.
2 mA / cm for activation of this battery²The battery was charged to 4.2 V at room temperature. Further, the battery was kept at 55 ° C. in a charged state, and aging was performed for 3 days. The above battery was charged with a charge end voltage of 4.2 V (open circuit voltage (OCV)), a discharge end voltage of 2.8 V (circuit voltage), 10 mA / cm.²Charge / discharge repeatedly under the condition of current density (equivalent to 1C), and after completion of 100 cycles, 2 mA / cm²(Equivalent to 0.2C) The discharge capacity of the discharge was measured, the maintenance ratio with respect to the initial discharge capacity was measured, and the cycle life of the battery was evaluated. In addition, as a test for evaluating the safety of the battery, the degree of heat generation was evaluated when a thermistor was fixed to the main body of the battery in a charged state, and a nail was pierced into the battery at room temperature to short-circuit the inside. This test was conducted five times for each battery.
[0039]
The results of evaluation of discharge capacity and safety evaluation for the above batteries are summarized in Table 1. Here, the safety evaluation results were classified as heat generation in which level A had a maximum exothermic temperature of 100 ° C. or less and level B exceeded 100 ° C.
[0040]

[0041]
From the comparison of Table 1, the secondary battery according to the constitution of the positive electrode and negative electrode materials carrying the protective layer described in the present invention is compared with the secondary battery using the cobalt nickel oxide based active material for the positive electrode, It can be seen that the battery performance is superior in terms of life and safety performance.
[0042]
【The invention's effect】
  According to the present invention,The composition of the positive electrode active material is another element-doped lithium nickel cobalt composite oxide, and the composite oxide is mainly composed of tin oxide having an amorphous structure as the negative electrode active material.By increasing the discharge capacity of the secondary battery, it is possible to provide a lithium ion non-aqueous electrolyte secondary battery excellent in cost,By using a non-aqueous electrolyte secondary battery comprising a positive electrode or a negative electrode with a protective layer coated on the active material mixture layer, a secondary using a conventional lithium nickel cobalt oxide based active material for the positive electrode Providing lithium-ion secondary batteries with superior cycle performance and safety performance compared to batteriesbe able to.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a cylinder type battery used in Examples.
[Explanation of symbols]
8 Positive electrode sheet
9 Negative electrode sheet
10 Separator
11 Cylindrical battery can
12 Battery cover that also serves as the positive terminal
13 Gasket
14 Safety valve

Claims (10)

In a secondary battery composed of a positive electrode using a lithium-containing metal composite oxide as an active material, a negative electrode using a metal composite oxide having an amorphous structure mainly containing tin oxide as an active material, and a non-aqueous electrolyte, cathode active material, Li _x Ni _1-y Co group 13 of the _{yz M z O 2-a X} b (M periodic table, elements of group 14, Mn, Fe, Ti, Zr , Nd, La , Cu, V, Sm, W, Zn, Y, Mg, Sr, Ca, Ba, Cs, Na, P, X is a halogen element, and 0.2 <x ≦ 1. 2,0 <y ≦ 0.5, z <y, 0 <z <0.5, 0.01 ≦ a ≦ 0.5, 0.01 ≦ b ≦ 2a) Lithium ion non-aqueous electrolyte secondary battery characterized by being a thing.   The lithium ion nonaqueous electrolyte secondary battery according to claim 1, wherein the X is F (fluorine).   3. The lithium ion nonaqueous electrolyte secondary battery according to claim 2, wherein M is one or more elements selected from Mn, Fe, Ti, B, Al, Sn, Si, Ga, and Mg. A positive electrode having a lithium-containing metal composite oxide as an active material, a negative electrode having a metal composite oxide having an amorphous structure mainly containing tin oxide as an active material, and a non-aqueous electrolyte. One of the Claims 1-3 characterized by being coated continuously with the active material mixture layer on one surface, and the protective layer containing the particle | grains of an electrically insulating inorganic substance being coat | covered. The lithium ion non-aqueous electrolyte secondary battery according to item.   5. The protective layer according to claim 4, wherein a protective layer mainly comprising one or more kinds of particles selected from aluminum oxide, titanium oxide, silicon oxide, and zirconium oxide is coated as an electrically insulating inorganic substance. Lithium ion non-aqueous electrolyte secondary battery. Active material of the negative electrode, further periodic table Group 1, Group 2, Group 13, Group 14, claim 1, Group 15 transition metal, characterized in that it comprises one or more selected from halogen The lithium ion non-aqueous electrolyte secondary battery according to -5. The negative electrode active material is an amorphous complex oxide mainly containing tin, and has a general formula Sn _x M ¹ _1-x M ² _y O _z (M ¹ is one or more selected from Mn, Fe, Pb, Ge) the, M ² represents Al, B, P, Si, group 1 of the periodic table, group 2, group 3, two or more elements selected from halogen element, 0 <x ≦ 1, 0.1 ≦ y ≦ 3, 1.65 ≦ z ≦ 4.5) Amorphous composite oxidation mainly comprising tin obtained by inserting lithium into a negative electrode active material precursor capable of occluding amorphous lithium The lithium ion nonaqueous electrolyte secondary battery according to claim 1, wherein the lithium ion nonaqueous electrolyte secondary battery is a product. The lithium ion nonaqueous electrolyte secondary battery according to claim 1, wherein the nonaqueous electrolyte contains ethylene carbonate and LiPF ₆ . The lithium ion nonaqueous electrolyte secondary battery according to claim 1, wherein the nonaqueous electrolyte contains ethylene carbonate, diethyl carbonate, and LiPF ₆ . The lithium ion nonaqueous electrolyte secondary battery according to claim 1, wherein the nonaqueous electrolytic solution contains ethylene carbonate, dimethyl carbonate, and LiPF ₆ .

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