JPH09161768A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve various characteristics of a battery by using a binder different from that of one face on the other face of at least one of two sheets in the battery spirally wound with a positive electrode sheet and a negative electrode sheet. SOLUTION: A battery has an electrode body spirally wound with a positive electrode sheet and a negative electrode sheet. A binder different from that of one face is used on the other face of at least one of two electrode sheets. The characteristics of the binders on the outer periphery and the inner periphery are changed, and the electric conductivities and ionic conductivities of the electrode materials on both faces are controlled to obtain the optimum battery. When the binder having the elastic modulus higher than that of the outer periphery is preferably used on the inner periphery, the bend on the inner periphery can be prevented. Thermoplastic resin or thermosetting resin may be used for the binder, and polyvinylidene fluoride is one of them, for example.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a battery using an electrode body in which a positive electrode, a negative electrode and a separator are spirally wound.

[0002]

2. Description of the Related Art In recent years, with the widespread use of portable devices such as video cameras, mobile phones, and notebook computers, there is an increasing demand for small, lightweight, high-capacity secondary batteries. Most of the secondary batteries currently used are nickel-cadmium batteries using an alkaline electrolyte, but it is difficult to increase the energy density because the average battery voltage is as low as 1.2V. Therefore, research on high energy secondary batteries using metallic lithium for the negative electrode has been conducted.

However, in a secondary battery using metallic lithium as a negative electrode, there is a risk that lithium will grow in a dendritic form due to repeated charging and discharging, causing a short circuit and ignition. In addition, since highly active metal lithium is used, the risk is inherently high, and there are many problems in using it for consumer use. In recent years, lithium ion secondary batteries using various carbonaceous materials have been devised as a device that solves such a safety problem and enables high energy peculiar to lithium electrodes. This method utilizes the fact that during charging, lithium ions are occluded (doping) in the carbonaceous material to have the same potential as that of metallic lithium, which can be used for the negative electrode instead of metallic lithium. In addition, doped lithium ions are released from the negative electrode during discharge.
(Dedoping) is performed to return to the original positive electrode material. When such a carbonaceous material that can be doped with lithium ions is used as the negative electrode, the problem of dendrite formation is small, and since there is no metallic lithium, it has excellent safety. Is being done.

As a secondary battery using an electrode using the above-mentioned carbonaceous material doped with lithium ions,
JP-A-57-208079, JP-A-58-93176, JP-A-58-192266,
JP-A-62-90863, JP-A-62-122066, JP-A-2-66856 and the like are known, and as the shape of the electrode body used in the lithium-ion secondary battery, a positive electrode, a negative electrode, and a separator are spirally wound. The shape is generally common.

However, when the spiral electrode body is used, the respective electrode sheets of the positive electrode and the negative electrode are deformed in a spiral shape, and a tensile force is applied to the electrode material on the outer peripheral surfaces of both the positive electrode sheet and the negative electrode sheet, and conversely The peripheral surface is compressed. Therefore, although the electrode material is applied in a flat plate state, the electrode material is stretched on the outer peripheral surface and the electrode material on the inner peripheral surface is contracted.

Further, in the spiral electrode body, when it is attempted to fill the constant volume with the electrode material as much as possible, it is necessary to increase the coating thickness of the electrode material, but as the thickness increases, the force applied to the outer peripheral surface and the inner peripheral surface is increased. Has a problem that the electrode material is cracked on the outer peripheral surface in the worst case.

Further, in the spiral electrode, the positive electrode in the spiral state,
Since it is necessary to optimize the charge / discharge characteristics of the negative electrode, especially the ion moving speed and the electric equivalence ratio (balance), a method is usually adopted in which the outer peripheral surface is coated more than the inner peripheral surface. However, in this method, after the electrode material is applied, the electrode sheet is liable to warp due to thermal expansion, thermal contraction, or pressure stretching in the steps of drying the electrode sheet at high temperature and pressing, etc., and then winding into a spiral shape. Occasionally, misalignment occurred, which eventually caused a short circuit due to the edge portions of the positive electrode sheet and the negative electrode sheet.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to obtain a battery having a high filling rate, a high capacity, good cycle characteristics, and high safety.

[0009]

The present inventors have achieved the present invention as a result of studying a battery having a high filling rate, a high capacity, good cycle characteristics, and high safety.

That is, according to the present invention, in a battery using an electrode body formed by spirally winding a positive electrode sheet and a negative electrode sheet, one surface of at least one of the positive electrode sheet and the negative electrode sheet is connected to the other surface. The present invention relates to a battery characterized in that different kinds of binders are used.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION As a result of intensive studies on high-performance batteries, the present inventors have found that a binder having different characteristics on the outer peripheral surface and the inner peripheral surface without causing a difference in thickness between the front and back during coating. It has been found that by using, it is possible to make the balance between the outer peripheral surface and the inner peripheral surface of the positive electrode and the negative electrode in the spiral shape proper.

That is, according to the present invention, in order to optimize the amount ratio (balance) of the active materials in the positive electrode and the negative electrode for electron transfer, the binder of the portion corresponding to the outer peripheral surface and the portion corresponding to the inner peripheral surface are formed. By changing the characteristics, the electric conductivity and ionic conductivity of the electrode material on the outer peripheral surface and the inner peripheral surface are controlled to obtain an optimum battery.

In the present invention, preferably, the elastic modulus of the binder is changed between the inner peripheral surface and the outer peripheral surface to optimize the balance. Furthermore, more preferably, by using a binder having a higher elastic modulus on the inner peripheral surface than the outer peripheral surface, it is possible to prevent bending that tends to occur on the inner peripheral surface and increase the thickness applied to the current collector. Becomes Further, the strength is increased without increasing the amount of the binder on the inner peripheral surface to prevent the electrode material from being deformed or damaged due to the bending applied to the inner peripheral surface when spirally revolving.
When the amount of the binder is increased to increase the strength of the inner peripheral surface, the moving speed of ions or electrons on the inner peripheral surface tends to decrease in some cases. It is desirable to increase the strength of the inner peripheral surface without increasing the migration resistance of ions or electrons, and for that purpose, it is preferable to use a binder having a high elastic modulus on the inner peripheral surface.

In the battery of the present invention, at least one surface of the electrode sheet has a binder different in type from the other surface.

A specific method for changing the charge / discharge characteristics of the outer peripheral surface and the inner peripheral surface is not particularly limited, but for example, the outer peripheral surface and the inner peripheral surface are made of different materials and / or different degrees of polymerization, molecular weights and the like. It is preferable to use a binder, and further, 2
Examples include a method of mixing more than one kind of binder, or a method of changing the compounding ratio. Further, even if the same kind of binder is used, it is effective to change the viscosity at the time of use or change the characteristics by applying heat treatment or the like.

The electrode sheet coated with the binder having different properties on the outer peripheral surface and the inner peripheral surface may be the positive electrode sheet only, the negative electrode sheet only, or both the positive electrode sheet and the negative electrode sheet, but at least the positive electrode sheet. Of the negative electrode sheets, it is more desirable to apply to an electrode sheet material having a thick coating thickness of the electrode material.

The binder used in the battery of the present invention may be either a thermoplastic resin or a thermosetting resin and is not particularly limited. It is also possible to use the binder in the form of a solution or emulsion. The amount of the binder added is usually 0.01 wt% to 40 wt% in the electrode material. Examples of the binder include various epoxy resins, cellulose resins, organic fluorine-based polymers, and copolymers, acrylic resins, organic chloro-based resins, polyimides,
Examples thereof include polyamide and polycarbonate. In particular, organic fluorine-based polymers and copolymers are preferable from the viewpoint of stability, and among them, polytetrafluoroethylene, polyvinylidene fluoride, propylene hexafluoride polymer and copolymers are preferable binders.

In the present invention, as the electrode material applied to the positive electrode, carbon fiber, carbonaceous material such as artificial or natural graphite powder, carbon fluoride, inorganic compound such as metal or metal oxide, organic polymer compound and the like are used. Can be used.

Further, in the present invention, as an electrode material applied to the positive electrode, a positive electrode active material used in a usual secondary battery can be mentioned. Examples of such a positive electrode active material include inorganic compounds such as transition metal oxides and transition metal chalcogens containing an alkali metal, polyacetylene, polyparaphenylene, polyphenylene vinylene, polyaniline,
Examples thereof include conjugated polymers such as polypyrrole and polythiophene, crosslinked polymers having a disulfide bond, and thionyl chloride. In the present invention, a lithium salt is preferably used as the electrolyte, but in this case, cobalt, nickel, manganese, molybdenum, vanadium, chromium, iron,
Transition metal oxides such as copper and titanium and transition metal compounds such as transition metal chalcogens are preferably used. In particular, L
iCoO ₂ , LiNiO ₂ , LiMn ₂ O ₄ , Li _y Ni
_1-x M _x O ₂ (M: Ti, V, Mn, or Fe),
_{Li 1-xa A x Ni 1} -yb B y O 2 ( however, A is at least one alkali or alkaline earth metal element,
Particularly preferred are Mg and Sr, B is at least one transition metal element, and preferably Co and F.
e) is most preferably used because of its large energy density. Among them, especially Li _1-xa A _x Ni
_1-yb B _y O ₂ is, 0 <x ≦ 0.1,0 ≦ y ≦ 0.3, -0.1 ≦ a ≦ 0.
1, -0.15 ≤ b ≤ 0.15 (However, when A and B are composed of two or more elements, x is the total number of moles of alkali or alkaline earth metal excluding Li, and y is total transition metal excluding Ni. It is the total number of moles of the element, and when y = 0, A contains at least one kind of alkaline earth metal). Further, in this case, it is possible to obtain active materials having different characteristics by changing the types, numbers, and compositions of A and B, or by using positive electrode materials with different x, y, a, and b. It is suitable.

When the positive electrode active material is an inorganic compound such as a metal or a metal oxide, a charge / discharge reaction occurs due to cation doping and dedoping, and when it is an organic polymer compound,
A charge / discharge reaction occurs due to anion doping and dedoping, but these are appropriately selected according to the required positive electrode characteristics of the battery and are not particularly limited.

The method for producing the electrode sheet by applying the positive electrode material and the negative electrode material to the current collector is not particularly limited, but due to the nature of the present invention, a solution dispersed in a solvent is applied together with a binder, a conductive material and the like. After that, a general method is to dry or attach the active material to the current collector using a conductive binder or a mixture of a conductive material and a binder.

The current collector of the present invention may be made of metal in the form of foil, mesh, lath or the like, but these are not particularly limited.

The positive electrode sheet and the negative electrode sheet can be obtained by applying an electrode material on one side or both sides of a current collector. If the electrode material is applied to one side of the current collector,
It is preferable to take the same form as in the case where two current collectors are overlapped with each other to coat both surfaces. However, in the case of single-side application, it is desirable to apply the electrode material to both surfaces of the current collector because it is difficult to heat or press the electrode sheet, and winding deviation easily occurs when the electrode sheet is spirally wound.

In the present invention, as the electrode material applied to the negative electrode, carbon fiber, artificial or natural graphite powder, carbonaceous material such as fluorocarbon, inorganic compound such as metal or metal oxide, organic polymer compound, etc. Can be used.

In the present invention, the electrode material applied to the negative electrode is preferably a carbonaceous material, more preferably carbon fiber. In this case, the carbon fiber is not particularly limited, but a carbon fiber obtained by firing an organic material into a fibrous state is generally used. Examples of the carbon fiber used in the present invention include P obtained from polyacrylonitrile (PAN).
AN-based carbon fiber, pitch-based carbon fiber obtained from pitch such as coal or petroleum, cellulose-based carbon fiber obtained from cellulose, vapor-grown carbon fiber obtained from gas of low molecular weight organic matter, livinyl alcohol, lignin, polychlorination Vinyl, polyamide, polyimide, phenolic resin, carbon fiber obtained by firing furfuryl alcohol and the like, depending on the characteristics of the electrode and the battery,
A carbon fiber that satisfies the characteristics is appropriately selected. further,
Among these carbon fibers, PAN-based carbon fibers and pitch-based carbon fibers are more preferably used. In particular, PAN-based carbon fiber is particularly preferable when it is used for a negative electrode of a secondary battery using a non-aqueous electrolyte containing an alkali metal salt such as lithium.

The diameter of the carbon fiber preferably used in the present invention is appropriately determined according to the form of each electrode or battery, but generally, carbon fiber having a diameter of 1 to 100 μm is preferably used, and a diameter of 3 to 3 is used. More preferred is 20 μm carbon fiber. It is also possible to use several kinds of carbon fibers having different diameters, if necessary.

Further, the length of the carbon fiber preferably used in the present invention is not particularly limited, but it is usually preferably 10
The thickness is 0 μm or less, more preferably 50 μm or less. If the length of the carbon fibers exceeds 100 μm, it tends to be difficult to apply the carbon fibers uniformly using a coater. Further, if the length of the carbon fiber is shorter than the diameter of the carbon fiber, the carbon fiber may be broken in the fiber direction. Therefore, the length of the carbon fiber is more preferably the carbon fiber diameter or more.

Examples of the conductive material that can be used in the battery of the present invention include carbon materials and metal powders, and particularly preferable conductive materials include various carbon blacks and artificial graphite. In the present invention, the amount of conductive material added and the particle size are
The optimum value varies depending on the material of the positive electrode and the negative electrode active material, the shape, the particle size, and the kind of the binder, the compounding amount, etc., so it should be determined experimentally, but preferably 0.5 to 0.5 of the entire electrode material. 30 wt%, more preferably 0.7 to 20 wt% is used. If the added amount is less than 0.5 wt%, the conductivity effect is poor, and if it exceeds 20 wt%, the capacity per unit weight of the electrode tends to decrease. In the present invention, the particle size of the conductive material is preferably such that the primary particle size is 1 nm to 100 μm, and more preferably
Fine particles of 5 nm to 20 μm are used. Those having a primary particle size of less than 1 nm are stable and difficult to produce, and those having a primary particle size of more than 100 μm tend to reduce the effect of addition.

Further, these electrode materials can be used as active electrodes for various batteries, such as primary batteries and secondary batteries.
What kind of battery is used is not particularly limited.

When used in a non-aqueous electrolyte secondary battery containing an alkali metal salt, a carbonaceous material doped with an alkali metal or a cation is used for the negative electrode and a material doped with an anion is used for the positive electrode.

When controlling the balance between the positive and negative electrodes by occluding lithium ions, firing the conductive material is a preferable method for controlling the characteristics of the conductive material. The firing temperature, time, atmosphere conditions, etc. This makes it possible to obtain a conductive material exhibiting optimum characteristics. Furthermore, it is more desirable to select a condition that does not impair the conductivity under these firing conditions.

The electrode material thus obtained can be used as an electrode for various batteries, and the type of battery is not particularly limited, but is preferably used as an electrode for a secondary battery. Particularly preferable secondary batteries include secondary batteries using a non-aqueous electrolyte solution containing an alkali metal salt such as lithium perchlorate, lithium borofluoride, and phosphorus hexafluoride / lithium.

The separator used in the present invention is not particularly limited as long as it prevents short circuit between the positive electrode and the negative electrode. It is desirable that the electrolyte has good permeability and does not become a resistance to transfer of electrons and ions. Typical materials include polyester, polyamide, polyolefin, polyacrylate, polymethacrylate, polysulfone, polycarbonate, and polytetrafluoroethylene. To be Among these, polypropylene, polyethylene, polysulfone and the like are particularly preferable because they are excellent in strength and safety. The shape of the separator is generally a porous film or a non-woven fabric, but a porous film is preferable because the filling rate in the battery can is easily increased. Further, the porous membrane is generally a symmetric membrane or an asymmetric membrane, but the strength,
In order to improve safety, it is also possible to use a composite membrane in which a plurality of types of membranes are laminated. The porosity of the porous film is preferably as high as possible in order to enhance the permeability of electrons and ions, but it may cause a decrease in the strength of the film and is therefore determined according to the material and the film thickness. Generally, the film thickness is 20-100 μm,
A porosity of 30-80% is desirable. Further, the diameter of the pores is preferably a range in which the active material detached from the electrode sheet, the binder, and the conductive material do not permeate, and specifically, the average pore diameter is 0.01
It is preferably about 1 μm.

As the electrolyte contained in the electrolytic solution used in the battery of the present invention, an alkali metal halide, perchlorate, thiocyanate, borofluoride, phosphorofluoride,
Arsenic fluoride, aluminum fluoride, trifluoromethyl sulfate, etc. are preferably used. Lithium salt, in particular, has the lowest standard electrode potential, and therefore a large potential difference can be obtained. Therefore, as the electrolyte contained in the electrolytic solution,
More preferably, a lithium salt is used.

The solvent used in the electrolytic solution used in the present invention is not particularly limited, and a conventional solvent can be used, and examples thereof include an acid or alkali aqueous solution or a non-aqueous solvent. Among these, as a solvent for the electrolyte of the secondary battery comprising a non-aqueous electrolyte containing an alkali metal salt, propylene carbonate, ethylene carbonate, dimethyl carbonate, γ- butyrolactone, N-methylpyrrolidone, acetonitrile, N, N- Dimethylformamide, dimethylsulfoxide, tetrahydrofuran, 1,3-dioxolane,
Methyl formate, sulfolane, oxazolidone, thionyl chloride, 1,2-dimethoxyethane, diethylene carbonate,
And derivatives and mixtures of these are preferably used.

The battery used in the present invention is not particularly limited as long as it is a battery using an electrode body wound in a spiral shape, but as a battery for mounting on portable equipment requiring high energy density, a negative electrode is used. A battery using an alkali metal as a material and a secondary battery using cation or anion doping to a carbonaceous material are effective.

The battery can loaded with the spiral electrode body is not particularly limited, but a battery can plated with iron for corrosion resistance, a battery can made of stainless steel, and the like have strength, corrosion resistance, It is preferable because it is excellent in workability. Further, it is possible to reduce the weight by using an aluminum alloy or various engineering plastics, and it is also possible to use various engineering plastics and a metal together.

Further, the shape of the spiral in the present invention does not necessarily have to be a true cylindrical shape, and may be an oblong cylindrical shape having an elliptical spiral cross section or a prismatic shape such as a rectangular spiral cross section. . In this case, the battery can can also take a shape corresponding to the shape of the electrode body. As a typical use form, a spirally-shaped electrode body and an electrolytic solution are loaded into a cylindrical battery can having a bottom, and leads taken out from the electrode sheet are sealed in a state of being welded to the cap and the battery can. The form is mentioned as the most common form, but is not limited to this form.

[0039]

The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited by this.

Example 1 The positive electrode material for the outer peripheral surface was LiCoO ₂ as the positive electrode active material.
80 wt%, 5 wt% polyvinylidene fluoride (KF2300 manufactured by Kureha Chemical Co., Ltd.) with a flexural modulus of 600 MPa as a binder,
Artificial graphite as conductive material (Nippon Graphite Industry Co., Ltd., SP-2
0) was prepared by mixing 15 wt%.

As the positive electrode material for the inner peripheral surface, 80% by weight of LiCoO ₂ was used as the positive electrode active material, and the bending elastic modulus was 1420 M as the binder.
Pa polyvinylidene fluoride (Kureha Chemical Co., Ltd., KF110
0) is 2.5 wt% and the flexural modulus is 600 MPa, polyvinylidene fluoride (Kureha Chemical Co., Ltd., KF2300) is 2.5 wt%, and artificial graphite (Nippon Graphite Industry Co., Ltd., SP-20) is 15 w as a conductive material.
It was prepared by mixing using t%.

Aluminum foil (thickness 20 μm) as a current collector
Using the above, the above positive electrode material is applied onto the current collector on both the outer peripheral surface and the inner peripheral surface at 300 g / m ² and subjected to heat treatment at 150 ° C., then 500 k
Pressing was performed under a pressure of gf / cm to obtain a positive electrode sheet.

The negative electrode material for the outer peripheral surface is used as a negative electrode active material.
PAN-based carbon fiber (Toray Industries, Inc., trading card T300) has an average length of 3
Using 80 wt% of 0 μm short fibers, 5 wt% of polyvinylidene fluoride (Kureha Chemical Co., Ltd., KF2300) with a flexural modulus of 600 MPa as a binder, artificial graphite (manufactured by Nippon Graphite Industry Co., Ltd.) , SP-20) was prepared by mixing 15 wt%.

The negative electrode material for the inner peripheral surface is used as a negative electrode active material.
PAN-based carbon fiber (Toray Industries, Inc., trading card T300) has an average length of 3
Polyvinylidene fluoride with a flexural modulus of 1420 MPa (Kureha Chemical Co., Ltd., KF1100) of 2.5 wt% and a flexural modulus of 600 MPa (Kureha) was used as a binder. KF2300 manufactured by Kagaku Co., Ltd. 2.
5 wt% and 15 wt% artificial graphite (SP-20, manufactured by Nippon Graphite Industry Co., Ltd.) as a conductive material were mixed and produced.

A copper foil (thickness: 10 μm) was used as a current collector, and the above-mentioned negative electrode material was applied on the current collector at 95 g /
After applying m ² and performing heat treatment at 150 ° C., pressing was performed at a pressure of 500 kgf / cm to obtain a negative electrode sheet.

A porous polypropylene film (manufactured by Daicel Chemical Industries, Ltd.,
A cylindrical electrode body was obtained by stacking as a separator of Celguard # 2500) and winding. No cracks occurred in these electrode bodies.

Further, this electrode body was loaded in a battery can having an internal volume of 5 cc, and a battery was prepared by using dimethyl carbonate containing 1M lithium borofluoride as an electrolytic solution. This battery is charged at a constant current and constant voltage with a charging current of 400 mA, a constant voltage value of 4.2 V and a charging time of 2 hours, and a discharge current of 200 mA and a discharge end voltage.
When the capacity test was performed at 2.5V, the initial discharge capacity was 382mAh,
The capacity retention rate was 85% after 100 times of charge and discharge.

Comparative Example 1 The same as Example 1 except that polyvinylidene fluoride (KF1100 manufactured by Kureha Chemical Co., Ltd.) having a bending elastic modulus of 1420 MPa was used as the binder for the outer peripheral surface and the inner peripheral surface of the positive electrode and the negative electrode. When an electrode body was manufactured in the same manner, the inner peripheral surface of the negative electrode was bent, and a cylindrical spiral electrode body could not be manufactured.

Comparative Example 2 The same as Example 1 except that polyvinylidene fluoride having a flexural modulus of 600 MPa (KF2300, manufactured by Kureha Chemical Co., Ltd.) was used for all the binders on the outer and inner surfaces of the positive and negative electrodes. When an electrode body was prepared in the same manner, an electrode body without cracks was obtained.

A battery was produced using this electrode body in the same manner as in Example 1, and a capacity test was conducted under the same conditions as in Example 1. The battery capacity was 365 mAh for the first time, and the capacity retention ratio after 100 cycles had elapsed. Was 82%.

[0051]

EFFECT OF THE INVENTION By using a binder of a kind different from the other surface on one surface of at least one electrode sheet of the positive electrode sheet and the negative electrode sheet, the filling rate is high, the capacity is high and the cycle characteristics are good. A highly safe battery can be obtained.

Further, by using binders having different elastic moduli on the outer peripheral surface and the inner peripheral surface of the electrode sheet, the charge and discharge characteristics of the positive electrode and the negative electrode in a spiral state, especially the ion moving speed and the electric equivalent ratio (balance). ) Can be optimized, and high-performance batteries can be manufactured.

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Claims (13)

[Claims] 1. In a battery using an electrode body formed by spirally winding a positive electrode sheet and a negative electrode sheet, at least one electrode sheet of the positive electrode sheet and the negative electrode sheet has one surface different from that of the other surface. A battery characterized by using a binder. 2. The binder used on at least one surface of at least one of the positive electrode sheet and the negative electrode sheet is a mixture of two or more binders. Batteries. 3. A positive electrode sheet and a negative electrode sheet, wherein at least one electrode sheet has a binder having a different elastic modulus from one surface of the other electrode surface.
The battery according to 1. 4. The battery according to claim 3, wherein a binder having a higher elastic modulus than the outer peripheral surface is used for the inner peripheral surface. 5. The battery according to claim 1, wherein a binder having an average molecular weight different from that of the other surface is used on one surface of at least one of the positive electrode sheet and the negative electrode sheet. . 6. The battery according to claim 1, wherein polyvinylidene fluoride is used as the binder. 7. The battery according to claim 1, wherein a lithium salt is used as an electrolyte. 8. The battery according to claim 1, wherein the electrode material applied to the positive electrode contains a transition metal compound. 9. The battery according to claim 1, wherein the electrode material applied to the negative electrode contains a carbonaceous material. 10. The battery according to claim 9, wherein the carbonaceous material is carbon fiber. 11. The battery according to claim 10, wherein the carbon fiber is a polyacrylonitrile-based carbon fiber. 12. The carbon fiber has a diameter of 1 μm to 100 μm,
A length of 100 μm or less, characterized in that
The battery according to 1. 13. The battery according to claim 12, wherein the length of the carbon fiber is not less than the diameter of the carbon fiber.