JPH08162158A - Nonaqueous secondary battery - Google Patents

Abstract

PURPOSE: To provide a nonaqueous secondary battery having high safety against overcharging and high voltage by adding a compound capable of inserting an anion at a specified voltage in a positive electrode mix containing a positive electrode active material. CONSTITUTION: A nonaqueous secondary battery is formed of a positive electrode active material containing Lix MO2 (0.05<=x<=1.2, M is Co, Ni, Mn, or Fe) or a compound of spinel structure, a negative electrode material, and a nonaqueous electrolyte. A compound for inserting an anion at 3.9V (to Li<+> /Li electrode) or more to enhance the internal resistance of the battery is contained in the positive electrode mix containing the above positive electrode active material. This compound is preferably an aromatic condensed polymer compound, for example, a carbonaceous compound obtained by baking a furan resin or cresol resin. This compound preferably has a 002 face spacing d002 of 3.5Å or more by X-ray diffraction, a crystallite size Lc less than 50, and a H/C ratio less than 0.04, and it is preferably contained in an amount of 0.1-10wt.% of the positive electrode mix in the combined use with acethylene black.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high voltage non-aqueous secondary battery which is safe against overcharge.

[0002]

2. Description of the Related Art In a high-voltage non-aqueous secondary battery, when it is overcharged, the temperature of the battery rises or a radical redox reaction occurs, which may cause the battery to ignite or burst. As measures against overcharging, voltage control of the charger, protection circuit outside the battery, battery internal pressure sensitive type current cutoff type safety valve inside the battery, internal pressure release valve installed in the safety valve, and also for the positive electrode mixture Has been practiced to include a pressure enhancer such as Li ₂ CO ₃ . However, the protection circuit may malfunction, and it is difficult for the current cutoff safety valve to maintain the contact for a long time,
Instability factors are included in the manufacturing process, such as the responsive pressure not being constant due to variations in manufacturing, and overcharging may occur in special cases. Japanese Patent Application Laid-Open No. 60-264052 describes a battery using a fired cresol resin as an electrode material.

[0003]

An object of the present invention is to obtain a high-voltage non-aqueous secondary battery with high safety against overcharge.

[0004]

Means for Solving the Problems The above-mentioned problems are addressed in a non-aqueous secondary battery composed of a positive electrode active material, a negative electrode material, and a non-aqueous electrolyte, with a positive electrode mixture containing the positive electrode active material containing 3.9 V (vs. Li ^+).
/ Li electrode) and a compound capable of inserting an anion above is included in the non-aqueous secondary battery. That is, when an overcharged state was introduced, the internal resistance of the battery increased due to the insertion of anions, so that the progress of overcharge was suppressed and the overcharge could be stopped.

The positive electrode or the negative electrode mixture contains a positive electrode, respectively.
In addition to the active material or negative electrode material, a conductive agent
Adhesives, dispersants, fillers, ion conductive agents, pressure enhancers, etc.
In addition to these, various additives can be included. Of the present invention
As the anion, an anion contained in the electrolytic solution is used.
Be done. For example, ClO_Four ^-, BF_Four ^-, PF₆ ^-, CF
₃SO₃ ^-, CF₃CO₂ ^-, AsF ₆ ^-, Sb
F₆ ^-, (CF₃SO₂)₂N^-, B_TenCl_Ten ^2-,
(1,2-dimethoxyethane)₂ClO_Four ^-, Lower fat
Group carboxylate ion, AlCl_Four ^-, Cl ^-, Br^-,
I^-Anions of chloroborane compounds, tetraphenylborane
Mention may be made of acid ions. In particular, at least Cl
O_Four ^-, BF_Four ^-, PF₆ ^-Or CF₃SO₃ ^-To
It is preferable to include.

As a compound capable of anion doping,
Examples thereof include a conductive polymer compound having a resonance structure or a carbonaceous compound. A polymer of an aromatic heterocyclic compound is preferable as the conductive polymer compound having a resonance structure.
For example, polyaniline, polyaniline derivative, polypyrrole, polypyrrole derivative, polythiophene, polythiophene derivative, polyphenylene, polyphenylene derivative, and polydisulfide compound are preferable. It is preferable that these compounds include compounds that are not partially anion-doped. Further, a carbonaceous compound is preferable as the compound capable of being anion-doped. For example, it is selected from natural graphite, artificial graphite, vapor grown carbon, calcined carbon of an organic substance, and the like. These also include compounds known as negative electrode materials. The carbonaceous compound may contain a slight amount or a graphite structure, but it is preferable that the carbonaceous compound has high amorphousness. Examples thereof include natural graphite, petroleum coke, pitch coke, coal, cresol resin-fired carbon, furan resin-fired carbon, polyacrylonitrile fiber-fired carbon, vapor-grown graphite, vapor-grown carbon, mesophase pitch-fired carbon, and polyacene. Among them, in particular, calcined carbon of an aromatic condensed polymer compound is preferable, and among them,
Furan resin fired carbon and cresol resin fired carbon are preferred. In addition to carbon, the carbonaceous compound may contain a heterogeneous compound. For example, B, P, N, S, etc. are 0
You may contain 10 weight%. It may also include SiC, the B ₃ C.

In order to operate the compound for anion doping safely, it is preferable to perform anion doping at 3.9 V (vs. Li + / Li electrode) or more.
3.9 to 10 V is preferable, 4.1 to 10 V is particularly preferable, and 4.3 to 6 V is particularly preferable. The anion doping also increases the resistance of the battery.
This can be shown from the fact that when the battery is overcharged, the battery voltage does not stagnate and the voltage continues to rise, and when charging is stopped at a high voltage, a large voltage drop occurs. 002 plane spacing (d ₀₀₂ ) in X-ray diffraction of anion-doping compound before anion doping according to the present invention
The value of is preferably 3.5 angstroms or more.
5 to 5 angstroms is preferred. Furthermore, 3.55
-5 Angstroms is preferred. Especially 3.55-
4.5 Angstroms is preferred. The crystallite size Lc in the X-ray diffraction of the anion-doping compound before anion doping of the present invention is preferably 50 or less. Especially, 40 to 1 is preferable. Further, the atomic ratio of hydrogen / carbon contained in the anion-doping compound before anion doping of the present invention is preferably 0.04 or less.
Further, it is preferably 0.03 or less, and particularly preferably 0.02 or less. As characteristic values of the above compound, it is desirable that the (d ₀₀₂ ) value is 3.5 to 5 Å, the Lc is 40 to 1, and the hydrogen / carbon atomic ratio is 0.001 or more and 0.04 or less. The presence or absence of anion doping is generally determined by whether or not d _{002 of} X-ray diffraction increases after the doping, but a compound having a relatively large d ₀₀₂ such as the compound of the present invention is difficult to evaluate by this method. As another method, the contained anion can be measured by an elemental analysis method, an atomic absorption method, an inductively coupled plasma emission spectroscopic analysis method, or the like.

As a method for synthesizing a calcined carbonaceous compound, a low molecular weight or high molecular weight organic compound as a raw material is pre-calcined in an oxidizing gas, or is calcinated in a vacuum or an inert gas without pre-calcination. It is preferable. The oxidizing gas is preferably oxygen, carbon dioxide gas, or steam. The content thereof is preferably 5 to 100%. The firing temperature is 200-4
000 ° C is preferred. Especially, 500-3500 degreeC is preferable and 700-2000 degreeC is especially preferable. The firing temperature is at least one stage, but multi-stage firing is also preferable.
Inert gas is nitrogen, argon, helium, xenon,
It is selected from krypton. The average particle size of the carbonaceous compound is preferably 0.1 to 100 μm, and particularly 0.1
-60 μm is preferable. In particular, it is preferable to have a particle size distribution of 90% or more in terms of volume in the range of 0.1 to 60 μm. The average surface area is preferably 1 to 200 m ² / g,
Particularly, ^{2 to} 50 m ² / g is preferable. True density is 1 to 3
Is preferred. Particularly, 1.5 to 2.6 is preferable. Crush,
A known crusher or classifier is used for the classification method. 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 pulverization and classification can be performed by a dry method or a wet method.

The conductive polymer having a resonance structure can be synthesized by chemical synthesis or electrolytic polymerization. The average size and average surface area are preferably at the same level as the carbonaceous compound. The conductive agent of the present invention can be used as a mixture with another conductive agent. As the other conductive agent, a carbonaceous compound or metal having low anion doping ability but high conductivity is used. For example, it preferably contains acetylene black, Ketjen black, graphite, aluminum, titanium and the like. The conductive agent of the present invention may be used in an amount of 0.1
It is preferable to include 15% by weight. Particularly, 1 to 7% by weight is preferable. The ratio of the low conductive agent to the high anion doping ability is preferably 0 to 20. Particularly, 0.1 to 10 is preferable. The compound of the present invention, in a normal charge / discharge state, is substantially used as a well-known conductive agent or current collector, and during abnormal charging,
Since it is the first compound to increase the battery resistance by anion doping, it must contain a positive electrode active material or a positive electrode material in addition to the compound of the present invention. Therefore, the compound of the present invention is disclosed in, for example, JP-A-60-2640.
It is different from the positive electrode active material or the positive electrode material carrying the active material as described in JP-A-52-52.

The positive electrode active material used in the present invention may be any compound capable of inserting and extracting light metal ions, and is particularly selected from transition metal oxides and transition metal chalcogenides. A transition metal oxide is particularly preferable, and a transition metal oxide containing lithium is particularly preferable. This oxide is preferably synthesized by firing a mixture of a lithium compound and a transition metal compound described below. Examples of the lithium compound include oxygen compounds, oxyacid salts and halides. As the transition metal compound,
A monovalent to hexavalent transition metal oxide, the same transition metal salt, or the same transition metal complex salt is used. Preferred lithium compounds used in the present invention include lithium hydroxide, lithium carbonate,
Lithium nitrate, lithium sulfate, lithium sulfite, lithium phosphate, lithium tetraborate, lithium chlorate, lithium perchlorate, lithium thiocyanate, lithium formate, lithium acetate, lithium oxalate, lithium citrate, lithium lactate, lithium tartrate, pyruvic acid Lithium, lithium trifluoromethanesulfonate, lithium tetraborate,
Examples thereof include lithium hexafluorophosphate, lithium fluoride, lithium chloride, lithium bromide and lithium iodide.

Preferred transition metal compounds used in the present invention include TiO ₂ , lithium titanate, acetylacetonato titanyl, titanium tetrachloride, titanium tetraiodide, titanyl ammonium oxalate and VO _d (d = 2 to 2.5). d =
Compounds of 2.5 are vanadium pentoxide), lithium compounds of VO _d , vanadium hydroxide, ammonium metavanadate, ammonium orthovanadate, ammonium pyrovanadate, vanadium oxosulfate, vanadium oxytrichloride, vanadium tetrachloride, lithium chromate. , Ammonium chromate, cobalt chromate, chromium acetylacetonate, MnO ₂ , Mn ₂ O ₃ , manganese hydroxide, manganese carbonate, manganese nitrate, manganese sulfate, ammonium manganese sulfate, manganese sulfite, manganese phosphate,
Manganese borate, manganese chlorate, manganese perchlorate,
Manganese thiocyanate, manganese formate, manganese acetate,
Manganese oxalate, manganese citrate, manganese lactate, manganese tartrate, manganese stearate, manganese fluoride, manganese chloride, manganese bromide, manganese iodide, manganese acetylacetonate, iron oxide (2,3 valent), ferric oxide , Iron hydroxide (2,3 valent), iron chloride (2,3 valent), iron bromide (2,3 valent), iron iodide (2,3 valent), iron sulfate (2,3 valent)
Valence), ammonium iron sulfate (2,3 valence), iron nitrate (2,
(Trivalent) iron phosphate (2,3 valent), iron perchlorate, iron chlorate, iron acetate (2,3 valent), iron citrate (2,3 valent), ammonium iron citrate (2,3 valent) , Iron oxalate (2, 3 valent), ammonium iron oxalate (2, 3 valent),

CoO, Co ₂ O ₃ , Co ₃ O ₄ , LiC
oO ₂ , cobalt carbonate, basic cobalt carbonate, cobalt hydroxide, cobalt sulfate, cobalt nitrate, cobalt sulfite, cobalt perchlorate, cobalt thiocyanate, cobalt oxalate, cobalt acetate, cobalt fluoride, cobalt chloride,
Cobalt bromide, cobalt iodide, hexaammine cobalt complex salt (as salts, sulfuric acid, nitric acid, perchloric acid, thiocyanic acid, oxalic acid, acetic acid, fluorine, chlorine, bromine, iodine), nickel oxide, nickel hydroxide, nickel carbonate, Basic nickel carbonate, nickel sulfate, nickel nitrate, nickel fluoride, nickel chloride, nickel bromide, nickel iodide, nickel formate, nickel acetate, nickel acetylacetonate, copper oxide (divalent), copper hydroxide, Copper sulfate, copper nitrate, copper phosphate, copper fluoride, copper chloride, ammonium chloride copper, copper bromide, copper iodide, copper formate, copper acetate, copper oxalate, copper citrate, niobium oxychloride, niobium pentachloride, penta Niobium iodide, niobium monoxide, niobium dioxide, niobium trioxide, niobium pentoxide, niobium oxalate, niobium methoxide, niobium ethoxide, niobium propoxide, niobium oxide Kishido, lithium niobate,
MoO ₃ , MoO ₂ , LiMo ₂ O ₄ , molybdenum pentachloride, ammonium molybdate, lithium molybdate, ammonium molybdophosphate, molybdenum acetylacetonate, WO ₂ , WO ₃ , tungstic acid, ammonium tungstate, and ammonium tungstophosphate are available. can give.

Particularly preferable transition metal compounds used in the present invention are TiO ₂ , titanyl ammonium oxalate, VO _d (d = 2 to 2.5), lithium compounds of VO _d , ammonium metavanadate, MnO ₂ and Mn _2. O
₃ , manganese hydroxide, manganese carbonate, manganese nitrate, manganese manganese sulfate, manganese acetate, manganese oxalate, manganese citrate, iron oxide (2 and 3 valent), ferric oxide, iron hydroxide (2 and 3 valent), Iron acetate (2,3 valent), iron citrate (2,3 valent), ammonium iron citrate (2,3 valent)
Valence), iron oxalate (2,3 valency), ammonium iron oxalate (2,
Trivalent), CoO, Co ₂ O ₃ , Co ₃ O ₄ , LiCoO
₂ , cobalt carbonate, basic cobalt carbonate, cobalt hydroxide, cobalt oxalate, cobalt acetate, nickel oxide, nickel hydroxide, nickel carbonate, basic nickel carbonate, nickel sulfate, nickel nitrate, nickel acetate, copper oxide (1,
Divalent), copper hydroxide, copper acetate, copper citrate, MoO ₃ , M
Examples include oO ₂ , LiMo ₂ O ₄ , WO ₂ and WO ₃ .

Particularly preferred combinations of lithium compounds and transition metal compounds used in the present invention are lithium hydroxide, lithium carbonate and / or lithium acetate and VO.
_d (d = 2 to 2.5), VO _d lithium compound, ammonium metavanadate, MnO ₂ , Mn ₂ O ₃ , manganese hydroxide, manganese carbonate, manganese nitrate, iron oxide (2,3 valent), 43 Iron oxide, iron hydroxide (2,3 valent), iron acetate (2,3 valent), iron citrate (2,3 valent), ammonium iron citrate (2,3 valent), iron oxalate (2,3 valent) , Ammonium iron oxalate (2,3 valent), CoO, Co ₂ O ₃ , C
o ₃ O ₄ , LiCoO ₂ , cobalt carbonate, basic cobalt carbonate, cobalt hydroxide, cobalt sulfate, cobalt nitrate, nickel oxide, nickel hydroxide, nickel carbonate, basic nickel carbonate, nickel sulfate, nickel nitrate, nickel acetate, Examples include MoO ₃ , MoO ₂ , LiMo ₂ O ₄ , and / or WO ₃ .

In addition to lithium compounds and transition metal compounds,
In general, compounds that enhance ionic conductivity, such as Ca ²⁺ ,
(For example, calcium carbonate, calcium chloride, calcium oxide, calcium hydroxide, calcium sulfate, calcium nitrate, calcium acetate, calcium oxalate, calcium citrate, calcium phosphate) or an amorphous network containing P, B, Si Forming agent (eg P ₂ O ₅ , Li
₃ PO ₄ , H ₃ BO ₃ , B ₂ O ₃ , SiO ₂ etc.) and the mixture may be fired. In addition, alkali metal ions such as Na, K and Mg and / or Si, Sn, Al and G
It may be mixed with a compound containing a, Ge, Ce, In, Bi or the like (for example, each oxide, hydroxide, carbonate, nitrate, etc.) and baked. Among them, it is preferably baked mixed with calcium carbonate or P ₂ O _5. The amount added is not particularly limited, but is preferably 0 to 20 mol%.

Examples of preferred positive electrode active materials that can be used in the present invention include transition metal oxides and transition metal sulfides. Among them, manganese dioxide, vanadium pentoxide, iron oxide, molybdenum oxide, molybdenum sulfide, cobalt oxide, iron sulfide, titanium sulfide and the like are preferable. In addition to the above-mentioned positive electrode active material, a lithium-containing transition metal oxide is mentioned as a preferable positive electrode active material that can be used together in the present invention. Particularly preferably, Li _x M _y O _z (where M = V,
Mainly at least one selected from Mn, Fe, Co and Ni), x = 0.05 to 1.2, y = 1 or 2, z
= 1.5 to 5). In addition to these, an alkali metal other than lithium, an alkaline earth metal, a transition metal other than M described above, or a group IIIB to V group B (Al,
Ga, In, Ge, Sn, Pb, Sb, Bi) and the like may be included. Moreover, P, B, etc. may be included.

Further preferred Lithium which can be used in combination with the present invention
The lithium-containing metal oxide positive electrode active material may be Li_xCo
O₂, Li_xNiO₂, Li_xCo_aNi_1-aO₂, L
i_xCo _bV_1-bO_z, Li_xCo_bFe_1-bO_z, L
i_xMn₂O_Four, Li_xMnO₂, Li_xMn₂O₃,
Li_xMn_bCo_2-bO_z, Li_xMn_bNi
_2-bO_z, Li_xMn_bV_2-bO_z, Li_xMn_bFe
_1-bO_z(Where x = 0.05 to 1.2, a = 0.1
0.9, b = 0.8 to 0.98, z = 1.5 to 5)
You can The most preferred lithium-containing compound that can be used in combination with the present invention
The transition metal oxide-containing positive electrode active material may be Li_xCo
O₂, Li_xNiO₂, Li_xCo_aNi_1-aO₂, L
i_xMn₂O_Four, Li_xCo_bV_1-bO_z(Where x =
0.05-1.2, a = 0.1-0.9, b = 0.9-
0.98, z = 2.02 to 2.3).

The preferred negative electrode material used in the present invention may be any compound capable of occluding and releasing light metal ions, and in particular, light metals, light metal alloys, carbonaceous compounds, inorganic oxides, inorganic chalcogenides, metal complexes, organic compounds. It is selected from molecular 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 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.

Inorganic oxides include transition metal oxides and semi-golden acids.
Selected from compounds. As transition metals, V, Ti, Fe,
Mn, Co, Ni, Zn alone or in combination
Selected from the combination. For example, Fe₂O₃, Co₂0₃,
VO₂(B), WO₂, WO ₃, MoO₂, MoO₃,
Lithium-containing transition metal oxides are preferred. Among them
Also Li_eM_fO_g(Where M = V, Ti, Mn, F
e, Co, Ni, at least one selected from Zn),
e = 0.1-3, f = 1 or 2, g = 1-5.5)
Is preferred. Among them, Li_pCo_qV_1-qO_r
(Where p = 0.1-2.5, b = 0-1, z = 1.3
To 4.5) are particularly preferable.

Further, as the half-gold group oxide, there is a periodic table II.
An oxide mainly composed of the elements of groups I to V is selected. example
For example, Al, Ga, Si, Sn, Ge, Pb, Sb, Bi
Or oxides consisting of a combination of these are selected.
Devour. For example, Al₂O₃, Ga₂O₃, SiO, S
iO₂, GeO, GeO₂, SnO, SnO₂, SnS
iO₃, PbO, PbO₂, Pb₂O₃, Pb₂O_Four,
Pb₃O_Four, Sb₂O₃, Sb₂O_Four, Sb₂O_Five, B
i₂O₃, Bi₂O_Four, Bi₂O_Five, Li₂SiO₃,
Li_FourSi₂O₇, Li₂Si₃O₇, Li₂Si₂O
_Five, Li₈SiO ₆, Li₆Si₂O₇, Li₂GeO
₃, Li_FourGeO_Four, Li₈GeO₆, Li₂Sn
O₃, Li₈SnO₆, Li₂PbO₃, Li_FourPbO
_Four, LiBiO ₂, Li₃BiO_Four, Li_FiveBiO_Five,
LiSbO_Four, Li_FourMgSn₂O₇, Li₂MgSn
₂O_Five, SnSi_0.01O_1.02, SnP_0.01O_1.03, Sn
B_0.3O _1.45, SnSi_0.7P_0.3O_2.75, SnSi
_0.7Ge_0.1P_0.2O_3.1, SnSi_0.3Al_0.1P
_0.3O_3.1, SnSi_0.3Al_0.1B_0.2P_0.3O_3.2
Oxides containing the above are preferred. Also inorganic chalcogena
As the id, the metal indicated by the above inorganic oxide, half-gold
It is selected from sulfides using genus. For example, TiS₂, G
eS, GeS₂, SnS, SnS₂, PbS, Pb
S₂, Sb₂S₃, Sb₂S _Five, SnSiS₃Including
The sulfide is preferred. Among them, SnO and SnO
₂, GeO, GeO₂, SnSiO₃, Li₂SnO₃
Compounds containing are preferred. Also, like these
Incorporating an amorphous network former into the Group III-V oxides.
Is preferred. For example, the oxides of B, P, Si, V
It is preferable to include it. For example, P₂O_Five, Li₃P
O_Four, H₃BO₃, B₂O₃, SiO₂, V₂O_FiveSuch
It is preferable to add and synthesize. For example, the above Sn
P_0.01O _1.03, SnB_0.3O_1.45, SnSi_0.7P_0.3
O_2.75, SnSi_0.7Ge_0.1P _0.2O_3.1, SnSi
_0.3Al_0.1P_0.3O_3.1, SnSi_0.3Al_0.1B
_0.2P_0.3O_3.2Are examples of such compounds. Above carbon
The negative electrode materials of organic compounds and oxides have high capacity, high discharge potential,
It is preferable because it provides high safety and high cycle performance.

The surface of the oxide positive electrode active material or negative electrode material used in the present invention can be coated with an oxide having a chemical formula different from those of the positive electrode active material or negative electrode material used. This surface oxide is preferably an oxide containing a compound that is soluble in both acidity and alkalinity. Further, a metal oxide having high electron conductivity is preferable. For example, PbO ₂ , Fe
₂ O ₃ , SnO ₂ , In ₂ O ₃ , ZnO and the like or oxides thereof preferably contain a dopant (for example, a metal having a different valence in the oxide, a halogen element, etc.). Particularly preferably, SiO ₂ , SnO ₂ , Fe ₂
O _3, ZnO, is a PbO _2. The amount of the surface-treated metal oxide is preferably 0.1 to 10% by weight based on the active material. Further, it is particularly preferably 0.2 to 5% by weight, and 0.1.
Most preferred is 3 to 3% by weight.

In addition to the above, the surface of the positive electrode active material or the negative electrode material can be modified. For example, the surface of the metal oxide is treated with an esterifying agent, a chelating agent,
Treatment with a conductive polymer, polyethylene oxide, etc. may be mentioned. Also, the surface of the negative electrode material can be modified. For example, the treatment may be performed by providing an ion conductive polymer or polyacetylene layer. Further, the positive electrode active material and the negative electrode material may be subjected to a purification step such as washing with water.

The average particle size of the positive electrode active material and the negative electrode material used in the present invention is not particularly limited, but is 0.1 to 50 μm.
Is preferred. Furthermore, 0.5-30 micrometers is preferable. A known crusher or classifier can be used to obtain a predetermined particle size. Examples thereof include a mortar, a ball mill, a vibrating ball mill, a satellite ball mill, a planetary ball mill, a swirling airflow type jet mill and a sieve. The crushing and classification operations may be wet or dry. 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 and the like can be added to the electrode mixture. The conductive agent for the negative electrode may be any electron-conductive material that does not undergo a chemical change in the constructed battery. Usually, natural graphite (scaly graphite, flake graphite, earthy graphite, etc.), artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber and metal (copper, nickel, aluminum, silver, etc.) powder,
Conductive materials such as metal fibers or polyphenylene derivatives can be included as one type or a mixture thereof. In particular, it is preferable to include graphite because the cycle property is improved. Further, it is particularly preferable to use graphite and acetylene black together. The amount added is not particularly limited, but is 1
-50% by weight is preferable, and 1-30% by weight is particularly preferable. For carbon and graphite, 1 to 15% by weight is particularly preferable. Furthermore, 1 to less than 5 wt% is preferable. The weight ratio of graphite to carbon black is graphite alone, 10/1 to 1 /
1 is preferred. Particularly, 5/1 to 2/1 is 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, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butadiene rubber, polybutadiene, fluororubber and polyethylene oxide. Can be mentioned. 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 2
-30% by weight is preferred. The distribution of the binder in the mixture may be uniform or non-uniform. 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 amount of the filler added is not particularly limited, but is preferably 0 to 30% by weight.

The electrolyte is generally dissolved in the solvent and the solvent.
Lithium salt (anion and lithium cation) to be solved
It is composed of As the solvent, propylene carbonate
-, Ethylene carbonate, butylene carbonate,
Dimethyl carbonate, diethyl carbonate, methyl
Ethyl carbonate, γ-butyrolactone, methyl formate
, Methyl acetate, 1,2-dimethoxyethane, tetrahi
Drofuran, 2-methyltetrahydrofuran, dimethyl
Sulfoxide, 1,3-dioxolane, formamide,
Dimethylformamide, dioxolane, acetonitril
, Nitromethane, ethyl monoglyme, triphosphate
Stell, trimethoxymethane, dioxolane derivative, suture
Luforane, 3-methyl-2-oxazolidinone, propyi
Len carbonate derivative, tetrahydrofuran derivative,
Non-preservatives such as ethyl ether and 1,3-propane sultone
Examples include rotonic organic solvents, one of these
Or, two or more kinds are mixed and used. Soluble in these solvents
As the cation of the lithium salt to be used, for example, ClO_Four
^-, BF_Four ^-, PF₆ ^-, CF₃SO₃ ^-, CF₃CO
₂ ^-, AsF₆ ^-, SbF₆ ^-, (CF₃SO₂)₂N
^-, B_TenCl_Ten ^2-, (1,2-dimethoxyethane)₂C
10_Four ^-, Lower aliphatic carboxylate ion, AlCl4
 ^-, Cl^-, Br^-, I^-, A chloroborane compound
Nion, tetraphenyl borate ion can be mentioned,
These 1 type (s) or 2 or more types can be used.
Above all, it is preferable to include an acyclic carbonate.
Yes. For example, diethyl carbonate, dimethyl carbonate
, Methyl ethyl carbonate ethylene carbonate
Is preferably included. Also, ethylene carbon
Is preferably included. Also ethylene carbon
In addition to propylene carbonate, 1,2-dimeth
Xyethane, dimethyl carbonate or diethyl carbonate
LiCF is added to the electrolytic solution in which carbonate is appropriately mixed.₃SO₃,
LiClO_Four, LiBF_FourAnd / or LiPF₆
An electrolyte containing is preferred. In those supporting salts, LiP
F₆It is particularly preferable to include

The amount of these electrolytes to be 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 or the negative electrode material and the size of the battery. The volume ratio of the solvent is not particularly limited, but ethylene cabot to 1:
In the case of a mixed solution of 2-dimethoxyethane and / or diethyl carbonate, 0.4 / 0.6 to 0.6 / 0.
4 (1,2-dimethoxyethane and diethyl carbonate are both used in a mixing ratio of 0.4 / 0.6 to 0.6 /
0.4) is preferred. When adding propylene carbonate, 1 to 20 volume% is preferable. When adding dimethyl carbonate, 1 to 20 volume% is preferable.
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 together. 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, Li 4 Si
O ₄ , Li ₄ SiO ₄ -LiI-LiOH, x Li ₃ P
_{O 4 - (1-x)} Li 4 SiO 4, Li 2 SiS 3, it is effective and phosphorus sulfide compounds.

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 ion dissociating group, a polymer containing the ion dissociating group, and a mixture of 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.

As the separator, an insulating microporous thin film having a large ion permeability and a predetermined mechanical strength is used. Further, it is preferable to have a function of closing the holes at 80 ° C. or higher to increase resistance. A sheet or non-woven fabric made of olefin polymer such as polypropylene and / or polyethylene or glass fiber is used because of its resistance to organic solvent and hydrophobicity. The pore size of the separator is within the range generally used as a battery separator. For example, 0.01 to 10 μm is used. The thickness of the separator is generally within the range of battery separators. For example, 5 to 300 μm is used. After the polymer is synthesized,
The method for forming the holes may be a dry method, a drawing method, a solution or solvent removing method, or a combination thereof.

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.

The collector of the electrode active material may be any electron conductor as long as it does not undergo a chemical change in the constructed battery. For example, for the positive electrode, in addition to stainless steel, nickel, aluminum, titanium, carbon, or the like, a material obtained by treating the surface of aluminum or stainless steel with carbon, nickel, titanium, or silver is used. Particularly, aluminum or aluminum alloy is preferable. For the negative electrode, in addition to stainless steel, nickel, copper, titanium, aluminum, carbon, etc., as the material, copper, stainless steel surface treated with carbon, nickel, titanium or silver), Al-Cd alloy, etc. Used. Particularly, copper or copper alloy is preferable. 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 1 to 500
The one with μm is used.

The shape of the battery can be any of coins, buttons, sheets, cylinders, flats, corners 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 material is mainly used after being compressed into a pellet shape.
The thickness and diameter of the pellet are determined by the size of the battery. 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 material is mainly used after being applied (coated), dried, and compressed on the current collector. As a coating method, a general method can be used. For example,
Reverse roll method, direct roll method, blade method,
Knife method, extrusion method, curtain method, gravure method, bar method, dip method and squeeze method can be mentioned. Among them, the blade method, the knife method and the extrusion method are preferable. Application is 0.1-10
It is preferably carried out at a speed of 0 m / min. On this occasion,
By selecting the above coating method according to the solution physical properties and drying properties of the mixture, a good surface state of the coating layer can be obtained. The coating may be performed one by one or simultaneously on both sides. The coating may be continuous, intermittent or striped. The thickness, length and width of the coating layer are determined by the size of the battery, but the thickness of the coating layer on one side is particularly preferably 1 to 2000 μm in the compressed state after drying.

As a method for 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 width ratio of the negative electrode sheet to the positive electrode sheet is preferably 0.9 to 1.1. In particular,
0.95-1.0 is preferable. Since the content ratio of the positive electrode active material and the negative electrode material differs depending on the compound type and mixture formulation,
Although not limited, it can be set to an optimum value in terms of capacity, cycleability, and safety.

Stacked with the mixture sheet via a separator
After being fitted, the sheets can be rolled or folded.
Insert it into the can, connect the can and the sheet electrically, and
Inject and use the sealing plate to form a battery can. At this time,
The safety valve can be used as a sealing plate. Safety valve
In addition, equipped with various conventionally known safety elements
Is also good. For example, fuses,
Immetal, PTC element, etc. are used. Also, the safety valve
In addition to the above, cut into the battery can as a measure to increase the internal pressure of the battery can
Inserting method, gasket cracking method or sealing plate cracking
Method or cutting method with lead plate can be used.
Wear. In addition, the charger has built-in measures against overcharge and overdischarge.
Either have a protection circuit or connect it independently
Good. Also, as a measure against overcharge, increase the internal pressure of the battery.
It is possible to provide a method of cutting off the electric current. This and
A compound that raises the internal pressure in the mixture or in the electrolyte.
Can be included in. As a compound that increases internal pressure
Is Li₂CO₃, LiHCO ₃, Na₂CO₃, Na
HCO₃, CaCO₃, MgCO₃Such as carbonate
can give. Cans and lead plates are made of metal or
Alloys can be used. For example, iron, nickel, chi
Gold such as tan, chrome, molybdenum, copper, aluminum
A genus or an alloy thereof is used. Caps, cans,
Welding methods for sheets and lead plates are known methods (eg, direct current or
Is AC electric welding, laser welding, ultrasonic welding)
Can be Sealing agents for sealing are asphalt, etc.
It is possible to use conventionally known compounds and mixtures of
it can.

The application of the non-aqueous secondary battery of the present invention is not particularly limited. For example, when it is mounted on an electronic device, a color notebook computer, a black and white notebook computer, a sub notebook computer, a pen input computer, a pocket (palmtop). PC, notebook 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 disks, electric shavers, electronic translators, car phones, transceivers, power tools, electronic organizers, calculators, memory cards, tape recorders, radios, backup power supplies, memory cards, etc. Other consumer products include automobiles, electric vehicles, motors, lighting equipment, toys, game machines, road conditioners, irons, watches, strobes, cameras, medical equipment (pacemakers, hearing aids, shoulder massagers, etc.) and the like. Furthermore, it can be used for various military purposes and for space. It can also be combined with other secondary batteries, solar cells, or primary batteries.

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, L
i_xNiO₂, Li_xMnO₂, Li_xMn₂O_Four(This
Here, at least 1 selected from x = 0.05 to 1.2)
The compound of the present invention, and the conductive agent includes furan resin and / or
Or a cresol resin calcined carbonaceous compound alone, or
Including acetylene black. The positive electrode current collector is stainless
Net, sea, made from stainless steel or aluminum
It has a shape such as a toe, a foil, and a lath. As the negative electrode material,
Lithium metal, lithium alloy (Li-Al), carbonization
Compound, oxide (LiCoVO_Four, SnO₂, SnO, S
iO, GeO₂, GeO, SnSiO₃, SnSi_0.3
Al_0.1B _0.2P_0.3O_3.2), Sulfide (TiS₂, S
nS₂, SnS, GeS₂, GeS), etc.
It is preferable to use one kind of compound. Negative electrode current collector
Made of stainless steel or copper, net, sea
It has a shape such as a toe, a foil, and a lath. Negative positive electrode active material
The material used together with the negative electrode material is an electron conductive agent.
By mixing carbon materials such as acetylene black and graphite
Good. Binders are polyvinylidene fluoride, polyfluoro
Fluorine-containing thermoplastic compounds such as ethylene, acrylic acid
Polymer containing, styrene butadiene rubber, ethylene pro
Elastomer such as pyrene terpolymer alone or
It can be mixed and used. In addition, as an electrolyte,
Tylene carbonate, further diethyl carbonate,
Cyclic and acyclic carbonates such as dimethyl carbonate
Or a combination of ester compounds such as ethyl acetate
LiPF6 as the electrolyte₆And further includes LIBF
_Four, LiCF₃SO₃Used by mixing lithium salts such as
Preferably. Furthermore, as a separator, poly
Propylene or polyethylene alone or their
Combinations are preferred. The form of the battery is coin, button, or
It can be either linder, flat or square. The battery is wrong
Means to ensure safety in operation (eg, internal pressure release type safety
Valve, current cutoff safety valve, separator that increases resistance at high temperature
-) Is preferable.

[0040]

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 Synthesis Method of Furan Resin Calcined Carbonaceous Compound Commercially available furfuryl alcohol 50 g, commercially available phosphoric acid (8
5%) 0.25 g and distilled water 5 g are mixed, and 95-100
The mixture was kept at 0 ° C. and stirred and reacted for 10 hours. After the reaction, 1N-aqueous sodium hydroxide solution was added to adjust the pH to 4 to 5, and then water was removed from the system under reduced pressure. The obtained furan resin is further heated at 1100 at 500 ° C. for 2 hours under an argon atmosphere.
Firing at 3 ° C. for 3 hours gave a furan resin-fired carbonaceous compound. (Yield = 19 g) This carbonaceous compound was ground using a tungsten carbide vibrating mill to obtain an average particle size of 9.5.
A μm powder was obtained.

Example 2 Method for synthesizing cresol resin-calcined carbonaceous compound 50 g of a commercially available ortho-cresol novolac resin was calcined under an argon atmosphere at 500 ° C. for 2 hours and further at 1075 ° C. for 3 hours to obtain a cresol resin-calcined carbonaceous compound. .
(Yield = 20 g) This carbonaceous compound was pulverized using a tungsten carbide vibrating mill to obtain an average particle size of 8.5 μm.
Of powder was obtained.

Examples 3 to 4 The values of the d ₀₀₂ plane by the X-ray diffraction method, the crystallite length Lc of the compound of the present invention, the furan resin-calcined carbonaceous compound, and the cresol resin-calcined carbonaceous compound, and their hydrogen content. The atomic ratio of / carbon is shown in Table 1.

Examples 5-14 90% by weight of the positive electrode active material, 5% by weight of the furan resin-fired carbonaceous compound or cresol resin-fired carbonaceous compound synthesized in Example 1 or 2 as a conductive agent, and acetylene black. A positive electrode pellet (13 mmΦ, 0.35 g) obtained by compression-molding a mixture containing 1% by weight, an aqueous dispersion of polyvinylidene fluoride as a binder in a solid content of 3% by weight, and carboxymethylcellulose in a mixing ratio of 1% by weight. Was thoroughly dehydrated with a far infrared heater in a dry box (dew point −40 to −70 ° C., dry air) and used as a positive electrode pellet. Lithium-aluminum alloy (80:20 weight ratio, 15 mmΦ, 0.6 mm thickness) was used as the negative electrode material, artificial graphite was 94% by weight, conductive agent acetylene black was 3% by weight, and polyfluoride was used as the binder. A negative electrode pellet (13 mmΦ, 0.2 mm) obtained by compression-molding a mixture prepared by mixing an aqueous dispersion of vinylidene chloride at a solid content of 3% by weight.
0 g) was thoroughly dehydrated with a far infrared heater in the same dry box as above and used as a negative electrode material. Furthermore, L
iCoVO ₄ , SnO, or SnSiO ₃ is used,
88% by weight of these negative electrode materials, 6% by weight of scaly graphite as a conductive agent, 3% by weight of acetylene black, and an aqueous dispersion of polyvinylidene fluoride as a binder were mixed in a solid content of 3% by weight. Negative electrode pellets (13 mmΦ, 0.047, 0.058, 0.
056 g) was thoroughly dehydrated with a far infrared heater in the same dry box as above and used as a negative electrode material.

As the current collector, an 80 μm thick SUS316 net was welded to a coin can for both the positive and negative electrode cans. 250 μl of 1 mol / liter LiPF ₆ (2: 8 volume mixture of ethylene carbonate and diethyl carbonate) was used as the electrolyte, and a microporous polypropylene sheet and polypropylene non-woven fabric were used as the separator. It was impregnated and used. Then, 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 pellets 2 are enclosed between the negative electrode sealing plate 1 and the separator 3, and the positive and negative electrode mixture pellets 4 are 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 battery was operated at ₂ mA depending on the negative electrode material, such as Li-Al, graphite, LiCoVO ₄ , Sn.
In O and SnSiO ₃ , each is 4.4 to 3.5.
V, 4.1-3.0V, 4.2-2.0V, 4.2
After charging and discharging for 2 cycles to 2.8V and 4.2 to 2.8V, charging is further continued to 10V at a constant current of 12.5mA for 4 hours. Charge at a constant voltage at 10V. Then, each battery is heated and heated at 100 ° C./min. The average discharge voltage in the second cycle at that time, the reached voltage of overcharge, the temperature at which the extreme reaction occurs, the battery resistance after overcharge (1 kHz
z) is shown in Table 2. Battery resistance at standard charging (1kHz
All of z) were 10 to 13 Ω.

The abbreviations shown in Table 1 above are as follows. (A) Positive electrode active material, (b) Negative electrode material, (c) Conductive agent (d) Second cycle charge capacity, (e) Overcharge ultimate voltage, (f) Extreme reaction generation temperature, (g) Overcharge Battery resistance after (1kHz)

Comparative Examples 1 to 4 Compounds other than the present invention, acetylene black, artificial graphite,
Table 1 shows the values of the d ₀₀₂ plane and the crystallite length Lc of natural graphite and petroleum coke.

Comparative Examples 5 to 6 All of Examples 6 and 10 except that acetylene black or artificial graphite was used in place of the furan resin fired carbonaceous compound or the cresol resin fired carbonaceous compound of the above Examples 6 and 10. Batteries were made in the same manner, and the same tests as in Examples 6 and 10 were performed. The results are shown in Table 2.

Comparative Examples 7 to 11 The batteries using acetylene black instead of the furan resin of Comparative Examples 6 to 10 were not overcharged, that is, after repeating two cycles under standard charge and discharge conditions, 100 ° C./mi.
Heated at n. Table 3 shows the results.

[0049]

[Table 1]

[0050]

[Table 2]

[0051]

[Table 3]

In the batteries of Examples 6 to 15 using the compound of the present invention, the voltage continued to increase when continuously charged, reached to 10 V after about 2 hours, and then the constant voltage state was entered to decrease the current value. Come on. On the other hand, the batteries of Comparative Examples 5 to 6 which did not contain the compound of the present invention showed a stagnation of voltage at 4.8 to 4.9 V, indicating that overcharging further progressed.
Further, from the table, the temperature at which the radical reaction occurs is higher in the battery containing the compound of the present invention than in the battery not containing it. Moreover, since the value is almost the same as that of the battery which is not overcharged, it indicates that the battery is not overcharged. Further, in the batteries using the compound of the present invention, the batteries of Examples 5 to 14 were lightly burst by heating after overcharging, whereas the batteries of Comparative Examples 5 to 6 were violently burst. Further, in the battery containing the compound of the present invention, when the charging is stopped at 5.5 V, the voltage drop becomes large, so that it is shown that the resistance of the battery becomes large when it is overcharged. Also,
As for the level of anion doping after overcharging, all of the conductive agents of Examples 5 to 14 had d002 increased by about 0.7 angstroms, but the conductive agents of Comparative Examples 5 to 6 showed an increase in the range of measurement error. It was inside. The above results are
Similar results were obtained with a cylindrical battery. The same was true when the positive electrode active material was LiNiO ₂ .

[0053]

INDUSTRIAL APPLICABILITY In a non-aqueous secondary battery comprising a positive electrode active material, a negative electrode material and a non-aqueous electrolyte, the positive electrode mixture contains 3.9 V (such as a furan resin fired carbonaceous compound or a cresol resin fired carbonaceous compound). By including a compound capable of inserting an anion above the Li ⁺ / Li electrode), a non-aqueous secondary battery that is safe for overcharging could be obtained.

[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 (14)

[Claims] 1. In a non-aqueous secondary battery comprising a positive electrode active material, a negative electrode material, and a non-aqueous electrolyte, a positive electrode mixture containing the positive electrode active material contains an anion at 3.9 V (vs. Li ⁺ / Li electrode) or more. Non-aqueous secondary battery containing a compound that can be inserted 2. The non-aqueous secondary battery according to claim 1, wherein the internal resistance of the battery is increased by inserting the anion. 3. The non-aqueous secondary battery according to claim 1, wherein the compound capable of inserting the anion is a carbonaceous compound. 4. The non-aqueous secondary compound according to claim 1, wherein the compound capable of inserting the anion is a carbonaceous compound obtained by calcining an aromatic condensation polymer compound. battery 5. The non-aqueous secondary battery according to claim 1, wherein the compound capable of inserting the anion is a carbonaceous compound obtained by firing a furan resin and / or a cresol resin. 6. The non-aqueous secondary battery according to claim 1, wherein the compound capable of inserting the anion has a 002 plane interval (d ₀₀₂ ) of 3.5 angstroms or more in X-ray diffraction. 7. The non-aqueous secondary battery according to claim 1, wherein the compound capable of inserting the anion has a crystallite size Lc of 50 or less in X-ray diffraction. 8. The non-aqueous secondary battery according to claim 1, wherein an atomic ratio of hydrogen / carbon contained in the compound capable of inserting the anion is 0.04 or less. 9. A compound capable of inserting the anion and acetylene black are used in combination.
Non-aqueous secondary battery described in 10. The non-aqueous secondary battery according to claim 1, wherein the compound capable of inserting the anion is contained in an amount of 0.1 to 10% by weight of the positive electrode mixture. 11. The non-aqueous secondary battery according to claim 1, wherein the anion contains at least PF ₆ ^−. 12. The non-aqueous secondary battery according to claim 1, wherein the solvent of the electrolyte contains at least an acyclic carbonate. 13. The positive electrode active material is 3.9 V (vs. Li ⁺ /
The non-aqueous secondary battery according to any one of claims 1 to 12, wherein the non-aqueous secondary battery has a charging return voltage equal to or higher than a Li electrode). 14. The positive electrode active material is Li _x MO ₂ (0.0
5 ≦ x ≦ 1.2 M is at least one type of Co, Ni, M
a compound mainly containing n and Fe and / or a spinel structure (at least one of Co, Ni, Mn and F)
e, including V).
Non-aqueous secondary battery described in