JPH0864245A - Nonaqueous electrolyte battery - Google Patents

Abstract

PURPOSE: To improve a discharging characteristic, safety, and a cycle properly by comprising the battery of positive electrode active material, negative electrode active material, and nonaqueous electrolyte, and using a compound containing carbonic acid metallic salt for the negative electrode active material. CONSTITUTION: In a compound used for negative electrode active material, a crystalline structure is changed when charging is carried out (for example, when lithium is adsorbed), however, the changed structure (for example, amorphous) is not basically changed after/before the following charging/discharging. In other words, compounds containing carbonic acid metallic salt such as oxalic acid, tartaric acid, ethylene diamine tetraacetic acid, ethylene diamine triacetic acid, citric acid, and lactic acid are used for the negative electrode active material. Cation compound of carbonic acid metallic salt contains a single metal or plural combined metals selected from transition metals or semimetals. In this way, higher discharging voltage, higher discharging capacity, and improved cycle property can be obtained.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a non-aqueous secondary battery having improved discharge characteristics, cycle characteristics and safety.

[0002]

2. Description of the Related Art Positive transition metal oxides for non-aqueous secondary batteries
As a polar active material, LiMn₂O_Four, Li₂MnO₃, Γ-
βMnO₂And LiMn₂O_FourComposite oxide of γ-βMnO₂
And Li ₂MnO₃Composite oxide of LiCoO₂, LiCo
_0.5Ni_0.5O₂, LiNiO₂, V₂O_Five, Amorphous V₂O_Five,
V₆O₁₃, LiV₃O₈, VO₂(B), TiS₂, Mo
S₂, MoO₃, LiMo₂O_FourJP-A-58-220
No. 362 and No. 55-136131.
Have been. Similarly, as the negative electrode active material, lithium is used.
Metals and lithium alloys are typical, but they are used
Lithium metal grows in a dendritic manner during charging and discharging,
Or the dendritic metal itself is highly active and ignites.
There is a danger of In contrast, recently, lithium
Practical use of calcined carbonaceous material that can insert and release
Is starting to appear. The disadvantage of this carbonaceous material is that
Since it is electrically conductive, it can be carbonized during overcharging and rapid charging.
Lithium metal may deposit on the
In some cases, dendritic metal will be deposited. Avoid this
In order to reduce the amount of positive electrode active material,
And adopting a method to prevent overcharging.
However, the latter method limits the amount of active material.
Therefore, the discharge capacity is also limited. Also charcoal
Since the material has a relatively low density, it has a capacity per volume
The discharge capacity is limited by the double meaning of being low.
Becomes In contrast, lithium metal or lithium alloy
Alternatively, as a negative electrode active material other than carbonaceous material, lithium
TiS that can store and release um₂, LiTi
S₂, A transition metal oxide having a rutile structure, for example, WO₂, L
i_xFe (Fe₂) O_FourSpinel compounds such as electrochemistry
Synthetically synthesized Fe₂O₃Lithium compound, Nb₂O_Five,
Iron oxide, FeO, Fe₂O₃, Fe₃O_Four, Cobalt oxide,
CoO, Co₂O₃, Co₃O_FourIt has been known. these
All of the compounds have high redox potentials, so they are as high as 3V
High-capacity non-aqueous secondary battery with discharge potential has been realized.
Not not. The negative electrode active material has a crystalline structure before and after charge and discharge.
Basically has the same property that it does not change
It On the other hand, when they are charged (for example, lithium
(Absorption of) changes the crystal structure.
The structure (for example, amorphous) basically changes before and after subsequent charging and discharging.
A material of a type that does not become solid has been proposed. As an example
LiCoVO_FourIs proposed.

[0003]

An object of the present invention is to obtain a non-aqueous battery having improved discharge characteristics, enhanced safety, and high cycleability.

[0004]

The above-mentioned object is achieved by using a compound containing a carboxylic acid metal salt in a non-aqueous secondary battery comprising a positive electrode active material, a negative electrode active material and a non-aqueous electrolyte. We were able to.

The preferred negative electrode material used with the carboxylic acid metal salt of the present invention is selected from light metals, light metal alloys, carbonaceous compounds, inorganic oxides, inorganic chalcogenides, and organic polymer compounds. Particularly preferred is a material containing a carbonaceous compound, an inorganic oxide, and an organic polymer compound.
These may be used alone or in combination. For example, combinations of light metals and carbonaceous compounds, light metals and inorganic oxides, light metals, carbonaceous compounds and inorganic oxides are also preferable. The negative electrode active material used in the present invention is preferably charged,
The crystal structure changes (for example, when lithium is absorbed), but the changed structure (for example, amorphous) is a type of compound that basically does not change before and after the subsequent charge and discharge. The negative electrode active material of the present invention preferably contains a carboxylic acid metal salt. The carboxylic acid is preferably an acid selected from C2 to C6 saturated polycarboxylic acids or C6 to C17 saturated monocarboxylic acids. Among them, oxalic acid, tartaric acid, ethylenediaminetetraacetic acid, ethylenediaminetriacetic acid, citric acid, and lactic acid are preferable. The addition amount is 5 to 1 with respect to the negative electrode active material.
The amount is 00 mol%, preferably 10 to 100 mol%, more preferably 20 to 100 mol%. The cation compound is selected from transition metals and metalloids. These may be included alone or in combination. The transition metal is 3 from Sc of atomic number 21 to Zn of 30.
9 Y to 48 Cd, 57 La to 80 Hg
The term "semimetal" means IIIB to V group B in the periodic table.
(Al, Ga, In, Si, Ge, Sn, Pb, Sb,
Bi). Among them, V, Co, F
e, Mn, Zn, Ti, Nb, Mo, Ge, Sn, Pb
Is preferably included. In particular, Zn, Mn, Sn,
Ge is preferred. Examples of carboxylates include zinc oxalate, manganese oxalate (+2), tin oxalate (+2),
Particularly preferred are ethylenediamine tetratin acetate (+4), germanium oxalate (+2), and aluminum lactate. In addition to the transition metals and semimetals, P, B, L
You may include i, Na, K, Ca, and Mg. The amount included is preferably 0 to 20% by weight.

As a side effect of the present invention, when the battery is overcharged or exposed to high temperature, the carboxylate of the present invention decarboxylates carbon dioxide gas before it ignites or explodes. It can be released to increase the internal pressure, destroy the safety valve to reduce the internal pressure, and cut off the current to reduce the damage. In addition to the above positive electrode active material, a preferable positive electrode active material used in the present invention is a lithium-containing transition metal oxide. Particularly preferably, Li _x M _y O _z (here, at least one selected from M = V, Mn, Fe, Co, and Ni is the main component), x = 0.3 to 1.1, y = 1 or 2, z = 1.5 to 5). In addition to these, alkali metals other than lithium, alkaline earth metals,
Transition metals other than M above, or Periodic Table III B to V
Group B (Al, Ga, In, Si, Ge, Sn, Pb, S
b, Bi) and the like. Moreover, P, B, etc. may be included. The addition amount is preferably 0 to 15 mol%. More preferable lithium-containing metal oxide positive electrode active materials used in the present invention are Li _x CoO ₂ , Li _x NiO ₂ , and L.
i _x Co _a Ni _1-a O ₂ , Li _x Co _b V _1-b O _z , Li _x Co _b
Fe _1-b O _z , Li _x Mn ₂ O ₄ , Li _x MnO ₂ , Li _x M
n ₂ O ₃ , Li _x Mn _b Co _2-b O _z , Li _x Mn _b Ni
_{2-b O z, Li x} Mn b V 2-b O z, Li x Mn b Fe 1-b O
_z (where x = 0.3 to 1.1, a = 0.1 to 0.9,
b = 0.8 to 0.98 and z = 1.5 to 5). The most preferable lithium-containing transition metal oxide positive electrode active material used in the present invention is Li _x CoO ₂ , Li _x
NiO ₂ , Li _x Co _a Ni _1-a O ₂ , Li _x Mn ₂ O ₄ , Li
_x Co _b V _1-b O _z (where x = 0.3 to 1.1, a = 0.
1 to 0.9, b = 0.9 to 0.98, z = 2.02
2.3).

The light metal is lithium, and the light metal alloy is lithium alloy (Al, Al-Mn, Al-Mg, A
1-Sn, Al-In, Al-Cd) are preferable. The carbonaceous compound is preferably a carbonaceous compound capable of inserting and releasing lithium ions or lithium metal. The carbonaceous compound is selected from natural graphite, artificial graphite, vapor-grown carbon, calcined carbon of organic matter, and the like. The carbonaceous compound is
It is preferable that even a slight amount of graphite structure is included. For example, natural graphite, petroleum coke, pitch coke, coal,
Examples include cresol resin-fired carbon, furan resin-fired carbon, polyacrylonitrile fiber-fired carbon, vapor-grown graphite, vapor-grown carbon, and mesophase pitch-fired carbon.
In addition to carbon, the carbonaceous compound may contain a heterogeneous compound. For example, B, P, N, S, etc. are 0-10.
It may be included by weight%. Moreover, you may contain SiC and BC.

The inorganic oxide is selected from transition metal oxides and semi-gold group oxides. As transition metals, V, Ti, Fe,
It is selected from Mn, Co, Ni, and Zn alone or a combination thereof. For example, Fe ₂ O ₃ , Co ₂ O ₃ , WO
₂ , WO ₃ , MoO ₂ , MoO ₃ and lithium-containing transition metal oxides are preferred. Among them, Li _e M _f O _g (here, at least one selected from M = V, Ti, Mn, Fe, Co, Ni, and Zn), e = 0.1 to 3, f = 1 or 2, g = 1 to 5.5) is preferable.

Among them, Li _p Co _q V _1-q O _r (where p = 0.1 to 2.5, b = 0 to 1, z = 1.3 to
4.5) is particularly preferred.

Another oxide or chalcogenide that may be used with the carboxylates of the present invention is the Periodic Table IV.
It is selected from compounds including a compound containing a semi-metal oxide of group B to VB or chalcogenide. For example, A
A compound containing an oxide or a sulfide consisting of 1, 1, Si, Ge, Sn, Pb, Sb, Bi alone or in combination thereof is preferable. For example, Al ₂ O ₃ , Si
O ₂ , GeO, GeO ₂ , SnO, SnO ₂ , SnSi
O ₃ , PbO, PbO ₂ , Pb ₂ O ₃ , Pb ₂ O ₄ , Pb
₃ O ₄ , Sb ₂ O ₃ , Sb ₂ O ₄ , Sb ₂ O ₅ , Bi ₂ O ₃ , Bi
₂ O ₄ , Bi ₂ O ₅ , Li ₂ SiO ₃ , Li ₄ Si ₂ O ₇ , Li ₂
Si ₃ O ₇ , Li ₂ Si ₂ O ₅ , Li ₈ SiO ₆ , Li ₆ Si ₂
O ₇ , Li ₂ GeO ₃ , Li ₄ GeO ₄ , Li ₈ GeO ₆ , L
i ₂ SnO ₃ , Li ₈ SnO ₆ , Li ₂ PbO ₃ , Li ₄ Pb
O ₄ , LiBiO ₂ , Li ₃ BiO ₄ , Li ₅ BiO ₅ , Li
An oxide containing SbO ₄ , Li ₄ MgSn ₂ O ₇ , Li ₂ MgSn ₂ O ₅ or the like is preferable. The inorganic chalcogenide is selected from the above-mentioned metals represented by inorganic oxides and sulfides using semimetals. For example, TiS ₂ , Ge
S, GeS ₂ , SnS, SnS ₂ , PbS, PbS ₂ , S
Sulfides containing b ₂ S ₃ , Sb ₂ S ₅ , SnSiS _{3 and the} like are preferred. Among them, SnO, SnO ₂ , GeO,
A compound containing GeO ₂ , SnSiO ₃ , and Li ₂ SnO ₃ is preferable. The oxide negative electrode active material is preferable because it provides high capacity, high discharge potential, high safety, and high cycleability.

The average particle size of the positive electrode active material and the negative electrode active material used in the present invention is not particularly limited, but is 0.03 to
75 μm is preferable. A known crusher or classifier can be used to obtain a predetermined particle size. For example,
Mortar, ball mill, vibrating ball mill, satellite ball mill,
Examples thereof include a planetary ball mill, a swirling airflow type jet mill and a sieve. The chemical formula of the compound obtained by firing was calculated from the weight difference of the powder before and after firing, as a measuring method, and as a simple method. A conductive agent, a binder, a filler, or the like can be added to the electrode mixture. The conductive agent may be any electron-conductive material that does not cause a chemical change in the constructed battery. Usually, natural graphite (scaly graphite, flake graphite, earthy graphite, etc.), artificial graphite, carbon black,
A conductive material such as acetylene black, Ketjen black, carbon fiber, metal (copper, nickel, aluminum, silver, etc.) powder, metal fiber or conductive polymer can be contained as one kind or a mixture thereof. The combined use of graphite and acetylene black is particularly preferred. The amount added is not particularly limited, but is preferably 1 to 50% by weight, and particularly preferably 2 to 30% by weight. For carbon and graphite, 2 to 15% by weight is particularly preferable.

As the binder, one kind of polysaccharides, thermoplastic resins and polymers having rubber elasticity or a mixture thereof can be used. Preferred examples are starch, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, regenerated cellulose,
Diacetyl cellulose, polyvinyl chloride, polyvinylpyrrolidone, polytetrafluoroethylene, polyvinylidene fluoride, polyacrylic acid, polyacrylate, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM,
Mention may be made of styrene butadiene rubber, polybutadiene, fluororubber and polyethylene oxide. When a compound containing a functional group that reacts with lithium, such as a polysaccharide, is used, it is preferable to add a compound such as an isocyanate group to deactivate the functional group. The amount of the binder added is not particularly limited, but is preferably 1 to 50% by weight, and particularly preferably 2 to 30% by weight. Even if the binder is evenly distributed in the mixture,
It may be uneven. Further, the binder may be added by any method such as powder, granules, dispersion (water, non-aqueous solvent) or latex. As the filler, any fibrous material that does not cause a chemical change in the constructed battery can be used. Generally, olefin polymers such as polypropylene and polyethylene, fibers such as glass and carbon are used. The addition amount of the filler is not particularly limited, but is 0 to
30% by weight is preferred.

The electrolyte is generally composed of a solvent and a lithium salt (anion and lithium cation) which is soluble in the solvent. As the solvent, propylene carbonate, ethylene carbonate, butylene carbonate,
Dimethyl carbonate, diethyl carbonate, γ-butyrolactone, methyl formate, methyl acetate, 1,2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, Aprotic organic solvents such as ethyl monoglyme, phosphoric acid triester, trimethoxymethane, dioxolane derivative, sulfolane, 3-methyl-2-oxazolidinone, propylene carbonate derivative, tetrahydrofuran derivative, ethyl ether, 1,3-propane sultone. Examples thereof include one type or a mixture of two or more types. Examples of the anion of the lithium salt dissolved in these solvents include ClO ₄ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , CF ₃ SO _{3
^{-, CF 3 CO 2 -,}} AsF 6 -, SbF 6 -, (CF 3 SO 2)
^{_{2 N -, B 10 Cl 10}} 2-, (1,2- dimethoxyethane) ₂
ClO ₄ ^-, lower aliphatic carboxylate ions, AlCl ₄ ^-,
Cl ⁻ , Br ⁻ , I ⁻ , an anion of a chloroborane compound,
Tetraphenyl borate ion may be mentioned, and one or more of these may be used. Above all, a mixture of propylene carbonate or ethylene carbonate and 1,2-dimethoxyethane and / or diethyl carbonate is mixed with LiCF ₃ SO ₃ and LiCl.
Electrolytes containing O ₄ , LiBF ₄ and / or LiPF ₆ are preferred.

The amount of these electrolytes to be added into the battery is not particularly limited, but it can be used in the required amount depending on the amount of the positive electrode active material or 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 solution of propylene carbonate or ethylene capote and 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 0.4 / 0.6 to 0.6 / 0.4). The concentration of the supporting electrolyte is not particularly limited, but is preferably 0.2 to 3 mol per liter of the electrolytic solution.

In addition to the electrolytic solution, the following solid electrolytes can be used. Solid electrolytes are classified into inorganic solid electrolytes and organic solid electrolytes. Li-nitrides, halides, oxyacid salts, and the like are well known as inorganic solid electrolytes. Among them, Li ₃ N, LiI, Li ₅ NI
_{2, Li 3 N-LiI-} LiOH, LiSiO 4, LiS
iO ₄ -LiI-LiOH, xLi ₃ PO 4-(1-x)
Li ₄ SiO ₄ , Li ₂ SiS ₃ , phosphorus sulfide compounds and the like are effective.

In the organic solid electrolyte, a polyethylene oxide derivative or a polymer containing the derivative, a polypropylene oxide derivative or a polymer containing the derivative, a polymer containing an ionic dissociative group, a mixture of the polymer containing an ionic dissociative group and the above aprotic electrolyte solution. A polymer matrix material containing a phosphoric acid ester polymer and an aprotic polar solvent is effective. Furthermore, there is also a method of adding polyacrylonitrile to the electrolytic solution. Also known is a method of using an inorganic and organic solid electrolyte in combination. Separation
As the target, an insulating thin film having a large ion permeability and a predetermined mechanical strength is used. A sheet or a non-woven fabric made of an olefin polymer such as polypropylene, polyethylene, a mixture of the two, or a laminate of the two or glass fiber is used because of its resistance to organic solvent and hydrophobicity. The pore size of the separator is
The range generally used for batteries is used. For example, 0.01 to 10 μm is used. The thickness of the separator is generally within the range for batteries. For example, 5
300 μm is used.

Further, other compounds may be added to the electrolyte for the purpose of improving discharge and charge / discharge characteristics. For example, pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, n-glyme, hexaphosphoric acid triamide, nitrobenzene derivative,
Sulfur, quinone imine dye, N-substituted oxazolidinone and N, N'-substituted imidazolidinone, ethylene glycol dialkyl ether, quaternary ammonium salt, polyethylene glycol, pyrrole, 2-methoxyethanol, A
lCl ₃ , a conductive polymer electrode active material monomer, triethylenephosphoramide, trialkylphosphine, morpholine, an aryl compound having a carbonyl group, 12-
Crown ethers such as Crown-4, hexamethylphosphoric triamide and 4-alkylmorpholine,
Examples include bicyclic tertiary amines, oils, quaternary phosphonium salts, and tertiary sulfonium salts.

Further, in order to make the electrolytic solution nonflammable, a halogen-containing solvent such as carbon tetrachloride or ethylene trifluoride chloride can be contained in the electrolytic solution. Further, the electrolytic solution may contain carbon dioxide gas in order to have suitability for high temperature storage. Further, the mixture of the positive electrode and the negative electrode can contain an electrolytic solution or an electrolyte. For example, a method is known in which the ion conductive polymer, nitromethane, and an electrolytic solution are contained. Further, the surface of the positive electrode active material can be modified. For example, the surface of the metal oxide may be treated with an esterifying agent, a chelating agent, a conductive polymer or polyethylene oxide. Also, the surface of the negative electrode active material can be modified.
For example, the treatment may be performed by providing an ion conductive polymer or polyacetylene layer. The collector of the electrode active material may be any electron conductor that does not cause a chemical change in the constructed battery. For example, in addition to stainless steel, nickel, aluminum, titanium, carbon, etc. as the material for the positive electrode, aluminum, stainless steel surface treated with carbon, nickel, titanium or silver, and for the negative electrode, stainless steel as the material In addition to steel, nickel, copper, titanium, aluminum, calcined carbon, etc., the surface of copper or stainless steel is treated with carbon, nickel, titanium or silver), Al-
Cd alloy or the like is used. It is also used to oxidize the surface of these materials. As the shape, in addition to the foil, 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. The thickness is not particularly limited, but one having a thickness of 1 to 500 μm is used.

The shape of the battery can be any of coins, buttons, sheets, cylinders, corners, flats and the like. When the shape of the battery is a coin or a button, the mixture of the positive electrode active material and the negative electrode active material is used by being compressed into a pellet shape. The thickness and diameter of the pellet are determined by the size of the battery. Further, when the shape of the battery is a sheet, a cylinder, or a corner, the mixture of the positive electrode active material and the negative electrode active material is applied (coated) on the current collector, dried and compressed, and is mainly used. As a coating method, a general method can be used.
Examples thereof include a reverse roll method, a direct roll method, a blade method, a knife method, an extrusion method, a curtain method, a gravure method, a bar method, a dip method and a squeeze method. The blade method, knife method and extrusion method are preferred. Application is 0.1-100
It is preferably carried out at a speed of m / min. At this time, a good surface condition of the coating layer can be obtained by selecting the above-mentioned coating method according to the solution physical properties and drying properties of the mixture. The thickness, length and width of the coating layer are determined by the size of the battery, but the thickness of the coating layer is particularly preferably 1 to 2000 μm in a compressed state after drying.

As a method of drying or dehydrating the pellets or sheets, a generally adopted method can be used. In particular, it is preferable to use hot air, vacuum, infrared rays, far infrared rays, electron beams, and low humidity air alone or in combination. The temperature is preferably in the range of 80 to 350 ° C, particularly 10
The range of 0 to 250 ° C. is preferable. The water content of the whole battery is preferably 2000 ppm or less, and the content of each of the positive electrode mixture, the negative electrode mixture and the electrolyte is preferably 500 ppm or less from the viewpoint of cycleability. As a pellet or sheet pressing method, a generally adopted method can be used, but a die pressing method or a calendar pressing method is particularly preferable. The pressing pressure is not particularly limited, but is 0.2 to 3 t /
cm ² is preferred. The press speed of the calendar press method is preferably 0.1 to 50 m / min. The pressing temperature is preferably room temperature to 200 ° C.

The mixture sheet is rolled or folded and inserted into a can, the can and the sheet are electrically connected, an electrolytic solution is injected, and a sealing plate is used to form a battery can. At this time, the safety valve can be used as a sealing plate. Other than safety valve,
Various conventionally known safety elements may be provided. For example, a fuse, a bimetal, a PTC element or the like is used as the overcurrent prevention element. In addition to the safety valve, as a measure for increasing the internal pressure of the battery can, a method of making a cut in the battery can, a method of cracking a gasket, a method of cracking a sealing plate, or a method of cutting with a lead plate can be used. Further, the charger may be provided with a circuit incorporating measures against overcharge and overdischarge. For the can and the lead plate, a metal or alloy having electrical conductivity can be used. For example, metals such as iron, nickel, titanium, chromium, molybdenum, copper and aluminum or alloys thereof are used. As a method for welding the cap, the can, the sheet, and the lead plate, a known method (eg, DC or AC electric welding, laser welding, ultrasonic welding) can be used. As the sealing agent for sealing, a conventionally known compound or mixture such as asphalt can be used.

The application of the non-aqueous secondary battery of the present invention is not particularly limited. For example, when it is installed in an electronic device, a color notebook computer, a black and white notebook computer, a pen input computer, a pocket (palm top) computer, a notebook. Type word processor, pocket word processor, e-book player, mobile phone, cordless phone handset, pager, handy terminal, mobile fax, mobile copy, mobile printer, headphone stereo, video movie, LCD TV, handy cleaner, portable CD, mini disk, Electric shaver, electronic translator, car phone,
There are transceivers, power tools, electronic organizers, calculators, memory cards, tape recorders, radios, backup power supplies, memory cards, etc. Other consumer products such as automobiles, electric vehicles, motors, lighting equipment, toys,
Game equipment, road conditioners, irons, watches, strobes, cameras, medical equipment (pacemakers, hearing aids, shoulder massagers, etc.), etc. Furthermore, it can be used for various military purposes and for space. It can also be combined with a solar cell.

A preferred combination of the present invention is the above chemical material.
It is advisable to combine the preferred components and battery components.
However, especially as a positive electrode active material, Li_xCoO₂, Li
_xNiO₂, Li_xCo_aNi_1-aO₂, Li_xCo_bV
_1-bO_z, Li_xCo_bFe_1-bO_z, Li_xMn₂O_Four,, L
i_xMnO₂, Li_xMn₂O₃, Li_xMn_bCo_2-bO_z,
Li _xMn_bNi_2-bO_z, Li_xMn_bV_2-bO_z, Li_xM
n_bFe_1-bO_z(Here, x = 0.8 to 1.1, a = 0.
1 to 0.9, b = 0.8 to 0.98, z = 1.5 to 5)
At least one compound containing, etc. as a negative electrode active material
, Tin (II) oxalate, zinc oxalate, manganese oxalate
At least one compound selected from
As a compound used with the carboxylic acid salts of
Metal, lithium alloy (Li-Al), carbonaceous compound,
Oxide (LiCoVO_Four, SnO₂, SnO, GeO₂,
GeO, SnSiO₃, Li₂SnO₃), Sulfide (Ti
S₂, SnS₂, SnS, GeS₂, GeS) etc.
It is preferred to use at least one compound. electrode
The mixture used with the active material should contain aceton as an electron conductive agent.
Carbon materials such as ethylene black and graphite, or
You may mix and use metal powder, such as ice ax. Binder
Is polyvinylidene fluoride, polyfluoroethylene, etc.
Fluorine-containing thermoplastic compound, styrene-butadiene rubber,
Elastomers such as ethylene-propylene terpolymer, po
Use sodium lyacrylate alone or in combination
be able to. In addition, as the electrolyte, ethylene carbonate
Cyclic and non-cyclic carbo such as bisulfite and diethyl carbonate
Or a combination of ester compounds such as ethyl acetate
As a supporting electrolyte, LiPF₆, LIBF_Four, LiC
F₃SO₃Lithium salt alone or mixed them
It is preferable to use. Furthermore, as a separator
Polypropylene or polyethylene alone or
A combination thereof is preferred.

[0024]

EXAMPLES The present invention will be described in more detail with reference to specific examples below, but the present invention is not limited to the examples as long as the gist of the invention is not exceeded. Example 1 As a negative electrode material, regarding (1) tin oxalate, (2) germanium oxalate, (3) manganese oxalate, (4) zinc oxalate, (5) ethylenediamine tetraacetic acid tin salt, and (6) aluminum lactate, A mixture of 90% by weight, 1% by weight of artificial graphite as a conductive agent, 2% by weight of acetylene black, 6% by weight of polyvinylidene fluoride as a binder, and 1% by weight of carboxymethylcellulose as a dispersant was prepared and used. Then, a pellet of 13 mmΦ and 60 mg was sufficiently dehydrated with a far infrared heater in a dry box (dew point −40 to −70 ° C., dry air). LiCoO ₂ as a positive electrode active material, acetylene black as a conductive agent, sodium polyacrylate, and carboxymethylmethylcellulose as a dispersant were prepared in a mixture of 95, 3, 1, and 1% by weight, respectively, and 13 mmΦ, 0. 35 g of pellets were thoroughly dehydrated with a far infrared heater in a dry box (dew point -40 to -70 ° C, dry air).

The positive and negative electrode cans were used as the current collector by welding a SUS316 net having a thickness of 80 μm to the coin can. 1 mol / l LiPF ₆ (2: 8 molar mixture of ethylene carbonate and diethyl carbonate) as electrolyte
Was used, and a microporous polypropylene sheet and a polypropylene non-woven fabric were used as a separator, and the non-woven fabric was impregnated with the electrolytic solution. And
A coin type lithium battery as shown in FIG. 1 was produced in the same dry box as above. In FIG. 1, the negative electrode mixture pellet 2 is enclosed between the negative electrode sealing plate 1 and the separator 3, and the positive electrode mixture pellet 4 is enclosed between the positive electrode case 6 having the current collector 5 and the separator 3. A gasket 7 is provided between the outer edge of the negative electrode sealing plate 1 and the outer edge of the positive electrode case 6. This lithium battery is 0.7
A charge / discharge test was performed at 4.2 to 2.0 V at a constant current density of 5 mA / cm ² . All tests started with charging. At that time, discharge voltage, discharge capacity, cycleability (10
Table 1 shows the discharge capacity change rate for 100 cycles.

[0026]

[Table 1]

Comparative Example The same as Example 1 except that spinel type Fe ₃ O ₄ was used as the negative electrode active material.

[0028]

EFFECT OF THE INVENTION In a non-aqueous battery comprising a positive electrode active material, a negative electrode active material and a non-aqueous electrolyte, by using a carboxylic acid metal salt as a negative electrode material, a high discharge voltage, a high discharge capacity and a good cycleability can be obtained. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a coin battery used in an example.

[Explanation of symbols]

 1 Negative Electrode Sealing Plate 2 Negative Electrode Mixture Pellet 3 Separator 4 Positive Electrode Mixture Pellet 5 Current Collector 6 Positive Electrode Case 7 Gasket

Claims (4)

[Claims] 1. A non-aqueous secondary battery comprising a positive electrode active material, a negative electrode active material, and a non-aqueous electrolyte, wherein at least one of the negative electrode active materials contains a carboxylic acid metal salt. 2. The non-aqueous secondary battery according to claim 1, wherein the cation of the metal salt of a carboxylic acid contains a cation of a transition metal or a metalloid. 3. The non-aqueous secondary battery according to claim 1, wherein the carboxylic acid salt contains tin (II) oxalate. 4. The non-aqueous secondary battery according to claim 1, wherein the positive electrode active material is a compound containing lithium and capable of reversibly inserting and releasing lithium.