JPH01194266A - secondary battery - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a secondary battery, and specifically relates to a secondary battery using a conductive material made of an oxidized polymer of a specific aniline compound as an electrode material. .

<Prior Art> In recent years, secondary batteries using conductive polymers made of various organic materials as electrode materials have been proposed.

The conductive polymer that serves as the electrode material for this type of secondary battery is
Doping with various anions, cations, and other dopants dramatically increases conductivity.

Then, a conductive polymer doped with anions is used as a positive electrode material, a conductive polymer doped with cations is used as a negative electrode material, and a solution containing a dopant is used as an electrolyte, and doping and dedoping are performed electrically. A battery that can be charged and discharged is constructed by chemically reversibly performing the process.

Such conductive polymers include polyacetylene, polypyrrole, polythiophene, and polyaniline, among which research and development are particularly active on oxidized polymers of aniline compounds, represented by polyaniline. Various proposals have been made to improve the properties of oxidized polymers of aniline compounds.

<Problem to be solved by the invention> However, the conductivity of conventionally used oxidized polymers of aniline compounds is still low, and the electrolyte absorbability is insufficient. Secondary batteries using such oxidized polymers have the problem of not being able to obtain satisfactory battery capacity and charge/discharge capacity efficiency, and further improvement of these battery characteristics is desired.

The present invention has been made in view of the above circumstances, and by using an oxidized polymer of aniline compounds with improved characteristics as an electrode material, it is possible to prevent damage to the battery container and to maintain high charge/discharge capacity efficiency over long cycles. The purpose is to provide a secondary battery that can be maintained.

Means for Solving the Problems The present inventors have conducted extensive studies on oxidized polymers of such specific aniline compounds, and have found that the intended purpose can be achieved by using the following means. I learned this and completed this invention.

That is, the present invention resides in a secondary battery characterized in that a conductive material obtained by treating an oxidized polymer of an aniline compound with an organic aliphatic carboxylic acid and forming an IG is used as at least one of a positive electrode and a negative electrode.

As the aniline compound used in the present invention, (in the formula,
R1 and R2 represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an allyloxy group, an amino group, an alkylamino group, and an arylamino group, and R3 and R4 represent a hydrogen atom,
Represents an alkyl group or an aryl group. ) Examples include aniline compounds represented by:

In the aniline compound represented by the above general formula (1), R1 and R2 are specifically hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, 5ec -butyl group 1, tert-
Butyl group, methoxy group, ethoxy group, n-propoxy group, n-butoxy group, phenyl group, tolyl group, naphthyl group, phenoxy group, methylphenoxy group, naphthoxy group, amino group, dimethylamino group, diethylamino group,
Represents a phenylamino group, diphenylamino group, methylphenylamino group, phenylnaphthylamino group, and R3
,, R4 is a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a phenyl group,
Represents a tolyl group or a naphthyl group.

Specific examples of such aniline compounds include aniline, methylaniline, ethylaniline, n-propylaniline, isopropylaniline, n-butylaniline, methoxyaniline, ethoxyaniline, n-propoxyaniline, phenylaniline, and tolylaniline. , naphthylaniline, phenoxyaniline, methylphenoxyaniline, naphthoxyaniline, aminoaniline, dimethylaminoaniline, diethylaminoaniline, phenylaminoaniline.

Examples include diphenylaminoaniline, methylphenylaminoaniline, and phenylnaphthylamineaniline.

Next, the organic aliphatic carboxylic acids used in the present invention will be explained in detail. Examples of such organic aliphatic carboxylic acids include saturated aliphatic monocarboxylic acids, saturated aliphatic dicarboxylic acids, unsaturated aliphatic monocarboxylic acids, and unsaturated aliphatic dicarboxylic acids. Examples of the saturated aliphatic monocarboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, invaleric acid, pivalic acid, lauric acid, myristic acid, barditic acid, and stearic acid. In addition, saturated aliphatic dicarboxylic acids include oxalic acid, malonic acid, succinic acid,
Examples include glutaric acid, adipic acid, pimelic acid, superric acid, azelaic acid, and sebacic acid. On the other hand, examples of unsaturated aliphatic monocarboxylic acids include acrylic acid, propiolic acid, methacrylic acid, crotonic acid, isocrotonic acid, and oleic acid. Furthermore, examples of the unsaturated aliphatic dicarboxylic acids include maleic acid and fumaric acid.

Among these organic aliphatic carboxylic acids, preferred are formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, invaleric acid, and acrylic acid, which are liquid at room temperature.

These organic aliphatic carboxylic acids may be used alone or in combination of two or more. Furthermore, it is also possible to dissolve these in an organic solvent or the like that does not affect the processing and use them in a solution state.

Next, a method for producing an oxidized polymer of an aniline compound used in the present invention will be explained.

This oxidized polymer can be produced by either an electrochemical polymerization (electrolytic polymerization) method or a chemical polymerization method. In the case of electrochemical polymerization, oxidative polymerization of the aniline compound is carried out by anodic oxidation. The electrolytic current at that time is in the range of 0.001 to 100 mA/c12, and the electrolytic voltage is in the range of 0.1 to 100 V, and a constant current method, a constant voltage method, and any other method can be used. Furthermore, this oxidative polymerization is carried out in an aqueous solution, a non-aqueous solvent such as an alcohol, or a mixed solvent thereof. Further, this oxidative polymerization is carried out in the presence of an acid. Specific examples of acids used at this time include HC, H2SO
4, HBF4°CF3COOH, HC204, etc., but are not limited to these.

On the other hand, when producing an oxidized polymer of an aniline compound by a chemical polymerization method, the aniline compound or a salt that is a reaction product of these compounds and an acid is oxidatively polymerized. The acids used at this time include HO2, HSo, HBF4
These include, but are not limited to, CF3000H2HC04. Oxidizing agents used in this chemical polymerization include, for example, peroxides such as potassium persulfate and ammonium persulfate, potassium dichromate and potassium permanganate, ferric chloride and ferric perchlorate, and peroxides such as potassium persulfate and ammonium persulfate. Examples include a combination of a dicopper compound and a nitrile compound. This oxidative polymerization is also carried out in an aqueous solution.

It is carried out in a non-aqueous solution such as an alcohol, a nitrile, or a mixed solvent thereof.

Further, in both of these electrochemical polymerization methods and chemical polymerization methods, other additives such as conductive materials can be added to the polymerization system and the polymerization can be carried out in the presence of these additives. Examples of such conductive materials include carbon black such as acetylene black, activated carbon, metal powder, and inorganic oxides. In addition, other additives are necessary, such as Teflon powder and polyethylene oxide.

Among the production methods described above, particularly preferred is a chemical polymerization method using an oxidizing agent containing a combination of a cupric compound and a nitrile compound.

Hereinafter, a method for producing an oxidized polymer of an aniline compound using an oxidizing agent consisting of a cupric compound and a nitrile compound will be described in detail.

First, when reacting an aniline compound with an acid, the acid i used is 0.01 to 1 mole of the aniline compound.
It is 10 times the mole, preferably 0.05 to 5 times the mole. The reaction temperature at this time is -50 to 150°C, preferably -20 to 100°C. The reaction time is related to the reaction temperature, but is usually 0.01 to 200 hours, preferably 0.5 to ioo hours.

Next, the aniline compound reacted with this acid is reacted with an oxidizing agent consisting of a cupric compound and a nitrile compound to form an oxidized polymer. As such a cupric compound,
Specifically, Cu(BF4)2, CuCbu2, cu(C,e04)2, Cu(PF6)2,
cu(ASF6)2,Cu(St)F6)2
, Cu (06H5SO3)2, Cu (CH306H4503)2, CuSO4, C
u (CF3803 > 2, CuZrF6, CuT
f F6 and Cu5f F6, which are usually used as compounds with water of crystallization or as aqueous solutions.

Specifically, the nitrile compound is acetonitrile, n
-propionitrile, isopropionitrile, n-butyronitrile, isobutyronitrile, acrylonitrile,
Examples include, but are not limited to, adiponitrile.

The amount of the cupric compound used is 0.1 to 100 times, preferably 0.2 to 50 times, per mole of the aniline compound or its salt.

The nitrile compound is used together with the cupric compound, and examples of how to use it include the following method.

1) After allowing a nitrile compound and a cupric compound to coexist in advance, an aniline compound or a salt thereof is allowed to act.

2) A cupric compound is allowed to act on a system in which an aniline compound or a salt thereof and a nitrile compound coexist.

3) A nitrile compound is allowed to act on a system in which an aniline compound or a salt thereof and a cupric compound coexist.

4) A system in which a cupric compound and a nitrile compound coexist is applied to a system in which an aniline compound or a salt thereof and a nitrile compound coexist.

5) A reaction product of a cupric compound and a nitrile compound is isolated in advance and allowed to react with an aniline compound or a salt thereof.

The amount of the nitrile compound used in these methods is 0.01 to io, ooo times, preferably 0.1 to 1,000 times, per mole of the cupric compound.

If the nitrile compound is a liquid substance, it can be used as a reaction solvent, or if it is a solid substance, any solvent such as water, alcoholic solvents such as methanol or ethanol, tetrahydrofuran, dioxane,
benzene.

Toluene, dichloromethane, dichloroethane.

Common organic solvents such as acetic acid can be used as reaction solvents.

The reaction temperature is -50 to 150°C, preferably -20°C.
~100°C. The reaction time is related to the reaction temperature, but is usually 0.5 to 200 hours, preferably 1.0 to 200 hours.
It is 100 hours.

The reaction product is a dark brown to black powdery substance. In the reaction in the presence of the above-mentioned solvent, after the reaction is completed and the solvent is removed by a conventional method, a liquid nitrile compound such as acetonitrile is used in the present invention. , react with a solvent such as propionitrile! - It is preferable to wash the product several times to dissolve and remove by-produced cuprous compounds, as it is possible to obtain a product with higher conductivity.

Next, in order to remove organic solvent-soluble components of the reaction product (oxidized polymer of aniline compound), this reaction product is washed several times with an organic amine compound. Specifically, organic amine compounds include pyridine, methylpyridine,
Examples include, but are not limited to, quinoline.

The amount of the organic amine compound to be used is 1 to ioooo times, preferably 2 times, the weight ratio of the aniline compound polymer.
~1ooo times. When the organic amine compound is a liquid substance, it is used as it is as a reaction solvent, and when it is a solid substance, it is used as an arbitrary solvent, such as alcohols such as methanol and ethanol, and tetrahydrofuran.

Common organic solvents such as ethers such as dioxane, aromatic hydrocarbons such as benzene and toluene, nitrites such as acetonitrile and propionitrile, and esters such as ethyl acetate and butyl acetate can be used. Note that an aqueous solution of an organic amine cannot be used because soluble components cannot be removed sufficiently.

The washing temperature is -20 to 150°C, preferably -100°C.
~100°C. The cleaning time is related to the cleaning temperature, but is usually 0.5 to 200. time, preferably 1.0
~100 hours.

Next, a method of treating the reaction product (oxidized polymer of aniline compound) with organic aliphatic carboxylic acids will be explained.

The amount of the organic aliphatic carboxylic acid used is 1° to 500 times, preferably 2 to 250 times, the weight of the oxidized polymer of the aniline compound.

If the organic aliphatic carboxylic acid is a liquid substance at room temperature, it may be used as it is as a solvent, or alcohol solvents such as methanol and ethanol, ether solvents such as diethyl ether, and even tetrahydrofuran, Common organic solvents such as dioxane, toluene, acetonitrile, etc. can be used.

In addition, when organic aliphatic carboxylic acids are solid substances at room temperature, they can be mixed with liquid organic aliphatic carboxylic acids and used in a dissolved state, or alcoholic solvents such as methanol and ethanol, diethyl Ether solvents such as ether, tetrahydrofuran, dioxane,
It may be used by dissolving it in a common organic solvent such as toluene or acetonitrile.

The treatment temperature is -10 to 150°C, preferably -15 to 150°C.
The temperature is 100°C. Processing time is related to processing temperature, but
Usually 0.5 to 100 hours, preferably 1.0 to 5 hours
It is 0 hours.

This reaction product has electrical conductivity as described in the Examples. In the present invention, the reaction product is molded into a desired shape by a known method such as pressure molding, and used as an electrode for a secondary battery. At this time, it is possible to use such a reaction product alone, but in order to increase the mechanical strength of the electrode and increase the conductivity to improve battery characteristics, thermoplastic resin or an appropriate conductive material may be used. It is preferable to add the like. As such a thermoplastic resin, any thermoplastic resin can be used without particular limitation as long as it is substantially insoluble in the electrolyte of the battery. Usually, molecules with a molecular ε of 10,000 or more are used, and specific examples include polyethylene, polypropylene,
Ethylene-propylene copolymer, ethylene-tetrafluoroethylene copolymer, polytetrafluoroethylene,
polytrifluoroethylene, polydifluoroethylene,
Tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polytrifluorochloroethylene, polyvinylidene fluoride, tetrafluoroethylene-ethylene copolymer, chlorotrifluoroethylene Ren-ethylene copolymer, polyamide,
Examples include polyester, polycarbonate, and modified polyolefin.

In addition, the conductive member may be made of a material that does not dissolve even after repeated charging and discharging, such as stainless steel, metals such as gold, platinum, nickel, copper, molybdenum, titanium, carbon, carbon fiber, etc. There are no particular restrictions, but
Particularly preferred are those that are lightweight and highly conductive. Specifically, examples include metal nets made of such metals, metal-plated fibers, metal-deposited fibers, metal-containing synthetic fibers, and nets, woven fabrics, and non-woven fabrics made of carbon fibers, carbon composite fibers, etc. .

The amount of addition of such thermoplastic resin and conductive member is as follows: heat, plastic resin 0.02 to 1000 weight ω parts, conductive member 2 to 10
It is preferable to use 0 weight R parts.

In the secondary battery of the present invention, there are cases in which electrodes made of such reaction products as electrode materials are used for both positive and negative electrodes, and cases in which this electrode is used only for one electrode, and metal or other electrodes are used for the second electrode. Totally bent oxides or other inorganic compounds, as well as known conductive polymers, organic compounds, and organometallic compounds other than the reaction products of the present invention may be used as electrode materials. For example, if an electrode using this reaction product is used only for the positive electrode, and a metal is used as the negative electrode material,
It is preferable to use a metal with an electronegativity of 1.6 or less as the metal constituting the negative electrode, and an example of such a metal is Li.

Examples include Na, MO, Aβ, and alloys thereof, with li and li alloys being preferred.

On the other hand, the electrolyte used in the secondary battery of the present invention is as follows:
For example, a solution in which an electrolyte is dissolved in an organic solvent is used. Examples of such electrolytes include salts with cations and anions such as metal cations and organic cations having an electronegativity of 1.6 or less. Examples of onium ions include quaternary ammonium ions, carbonium ions, oxonium ions, and the like. In addition, as anions, BF -1CJ204-1PF6-, AsF
-, CF3SO3-, l-1Br-1Cβ-1F
- etc. A specific example of such an electrolyte is lithium tetrafluoroborate (LiBF4).
), lithium perchlorate (L i CJ204'), lithium hexafluorophosphate (LiPF6), lithium tetrachloroaluminate (LiAλCβ4), tetraethylammonium tetrafluoroborate (Et4NBF)
4 >, tetra n-butylammonium perchlorate (nB
u4 NCJO4>, lithium trifluoromethanesulfonate (L!CF3303,), lithium iodide (L
Examples include, but are not limited to, ly, lithium bromide (Liar), and the like. Then, using the conductive material of the present invention for both the positive and negative electrodes, L! For example, if a battery is constructed using an electrolytic solution in which BF4 is dissolved as an electrolyte, during charging, BF4- in the electrolyte is added to the conductive material in the positive electrode, and the electrolyte is added to the conductive material in the negative electrode. Inside Li
+ is doped respectively. On the other hand, during discharge, BF -1 doped into the positive and negative electrodes! + are respectively released into the electrolyte.

In addition, as the organic solvent for dissolving the electrolyte, it is preferable to use an aprotic one with a high dielectric constant, such as nitrile, carbonate, ether, nitro compound, amide, sulfur-containing compound,
Chlorinated hydrocarbons, ketones, esters, etc. can be used. Moreover, two or more kinds of such solvents can also be used in combination. Representative examples of these include acetonitrile, propionitrile, butyronitrile, benzonitrile, propylene carbonate, ethylene carbonate,
Tetrahydrofuran, dioxolane, 1,4-dioxane, nitromethane, N,N-dimethylbormamide, dimethylsulfoxide, sulfolane, 1,2-dichloroethane, γ-butyrolactone, 1,2-dimethoxyethane, methyl phosphate, ethyl phosphate, etc. These examples include, but are not limited to.

The electrolytic solution of the present invention usually has a degree of o, ooi to 1
Used at 0 mol/λ, preferably 0.1 to 3 mol/λ
used in

In addition to being injected, such an electrolytic solution can also be used by impregnating an electrode made of the conductive material of the present invention in advance.

In addition, although the method described above has been described in which the conductive material is directly formed into an electrode without doping, the conductive material is doped with a dopant in advance, and then the conductive material as described above is used alone or in combination with the dopant. It is also possible to use a plastic resin by molding it into an electrode.

Further, in the present invention, in order to fix the electrode in the electrolyte, the electrode may be covered with a slat-like or holed glass, Teflon, polyethylene, plate, or the like.

Further, in the battery of the present invention, a porous membrane such as glass filter paper, Teflon, polyethylene, polypropylene, nylon, etc. may be used as the separator.

<Function> By treating with organic aliphatic carboxylic acids as in the present invention, the electrical conductivity of the oxidized polymer of the aniline compound is significantly improved compared to the untreated case, and this oxidized polymer , the number of pores with large radius increases.

By using this oxidized polymer of aniline compounds with good electrical conductivity in the electrodes of secondary batteries, the voltage increase during charging can be suppressed to a small level, and the resulting increase in voltage can cause problems such as decomposition of the electrolyte. As a result of suppressing the reaction, the charge/discharge capacity efficiency of the battery is improved and the cycle characteristics are improved.

In addition, this increase in the number of large-radius pores in the oxidized polymer increases the electrolyte's liquid-retaining properties, which improves the utilization rate of the oxidized polymer and increases the maximum charging and discharging per unit weight. 'The capacitance increases and the battery capacity can be increased.

<Example> The present invention will be specifically described below with reference to Examples.

Production example of conductive material 1 9.3 g of aniline (0°1 mo
1), and while stirring under a nitrogen atmosphere, add the following:
42% HBF4 aqueous solution 20.9 (
J (0.1 mol) was added dropwise over 10 minutes.

As the mixture was added, heat generation was observed, and the reaction solution became cloudy. Powder-like solid matter was precipitated in the reaction solution, and the solution appeared in the form of a slurry. After continuing stirring for 30 minutes, a pre-prepared 45% Cu (BF4 >2 aqueous solution 52.5%) was added thereto at room temperature (15-20°C).
A mixture of 7(1(0,1mof) and acetonitrile 600 (M and other agents) was added dropwise over 15 minutes.

As the mixture was added, a slight heat generation was observed, and the reaction liquid immediately turned black, and a powdery solid was precipitated in the reaction liquid to form a slurry. After continuing stirring for 4 hours, the mixture was left at room temperature overnight.

Thereafter, the reaction product was separated into a furnace, and 1 q of black powdery material mixed with white crystalline material was obtained. This was washed three times with 300 m, l of acetonitrile, and the white crystalline substance was removed by this operation.

The black powdery substance was then washed three times at room temperature with 300g of pyridine for 30 minutes each time, and further washed with 300IN of acetonitrile to remove the pyridine from the resulting black powdery substance. did. Then, when dried under reduced pressure at a temperature of 60°C, a black powdery substance 3
．． 0 g was obtained.

3.0 g of this black powdery substance was treated at room temperature with a mixed solution of 50 g of formic acid and 100 ml of ethanol for 2 hours, and then washed with ethanol and ioomρ. after that,
When dried under reduced pressure at a temperature of 60°C, 3.0g of black powdery substance
was gotten. Elemental analysis of this black powdery substance showed that
C74, 21%, H4, 63%, N14.49%, F
5.36%, assuming carbon is 6, C6,001
It was found that it corresponds to H4,501"1.00-FO,28.

Furthermore, as a result of measuring the electrical conductivity of this black powdery substance using the two-terminal method, it was found to be 6.3×10-10-
68C was obtained, and the semiconductor region WJ was found to be an organic semiconductor with (7) N conductivity.

The electrical conductivity was measured as follows. First, the black powdery substance obtained by the above treatment was sufficiently finely ground in a mortar, and then pressure-molded (1 ton/cI12) into a disk shape with a diameter of 1Q mm.

Next, this disk sample was sandwiched between two copper cylinders of the same size, a load of 1.2 g was applied from the top, and the conductor leads were taken out from the upper and lower copper cylinders and connected to a digital multimeter (Takedariken TR6851). death,
The electrical conductivity of the disk sample was measured using this meter.

Next, the specific surface area of the black material formed in this way,
When the pore radius distribution was measured using the mercury pressure method, the specific surface area was 13 m2/g, and the pore radius distribution was 20~
In particular, 60% of the pores had a radius of 100 Å or more.

゛, Conductive Material Comparative Example 1゜ The reaction was carried out in the same manner as in Production Example 1 above, and the reaction product was washed in the same manner with acetonitrile, pyridine, and acetonitrile, and then dried under reduced pressure at a temperature of 60°C to obtain polyaniline. Ta.

When this polyaniline was molded in the same manner as in Production Example 1 and its electrical conductivity was measured, it was found to be 9.8X 10'5CIIl-1
Met.

In addition, the specific surface area and pore radius distribution are respectively 13 m2/
g, 20 to 1000, and in particular, pores with a radius of 100 Å or more accounted for 45% of the total.

From the above results, it can be concluded that by treating the oxidized polymer of aniline compounds with organic aliphatic carboxylic acids, the electrical conductivity of the oxidized polymer increases and the number of pores with a large radius increases. confirmed.

Production Example 2 of Conductive Material An experiment was conducted in the same manner as Production Example 1, except that ioog propionic acid was used instead of formic acid, and 3.0 g of a black powdery substance was obtained.

The electrical conductivity of this material is 4.5x 10-60-6S'
Met. In addition, the specific surface area and pore distribution are each 1
3m2/(1,20-1000 people, especially 100Å
The number of pores having a radius greater than or equal to 56% of the total was 56%.

Manufacturing example of conductive material 3゜Ol-1-toluidine io, yg(0
, 1 mol), 9.9 J (0.1 mol) of 37% HCβ aqueous solution instead of HBF4 aqueous solution, 150 g of acetic acid instead of formic acid, and acetylene black O, sg were allowed to coexist when reacting the oxidizing agent. The reaction operation was carried out in the same manner as in Production Example 1, and 3.8 g of a black powdery substance was obtained.

The electrical conductivity of this material is 9.8x 10-60-6S'
The specific surface area and pore radius distribution are each 14 m2.
/g, 20 to 1,500 people, and in particular, pores with a radius of 100 Å or more accounted for 51% of the total.

Production example of conductive material 4 12.3 g of ortho-anisidine was placed in a 1° round bottom flask.
(0.1 mol), and while stirring under nitrogen atmosphere, add 42% HC under water cooling (0 to 5°C).
16.7 (0.1 mol) of β04 aqueous solution and 100 mN of distilled water were added over 10 minutes.

In this, ferric perchlorate hexahydrate 46.2 (J, (0
,1m01) with distilled water ioomu60%)-1cJ
204 aqueous solution 16.7 (1 (0,11 LQ)) and the mixture was added dropwise over 30 minutes. Then, 15
After stirring for 3 hours at <RTIgt;C,</RTI> the mixture was kept at room temperature (25 <0>C) overnight.

After that, the reaction product was separated from house to house, distilled water was 300 m, and Q was 300 m.
The washing process was repeated three times for 0 minutes each.

After this, acetonitrile, pyridine,
Washed with acetonitrile. This black powdery substance is
2009, washed with acetonitrile, and washed with 6
Drying under reduced pressure at 0° C. gave a black powdery substance of s, og.

The electrical conductivity of this material is 2.4X 10's cm'
The specific surface area and pore distribution are each 13m2/
20 to 1000 g, and in particular, pores with a radius of 100 Å or more accounted for 50% of the total.

Manufacturing example of conductive material 5 Distilled water, HBF4, and aniline were added to a glass container, and the concentration of HBF4 was 2. The concentration of Omol, 72 lJ was adjusted to 0.5 m0I.

Two Sass meshes (S LI S-316,400 mesh) each having a capacity of 1 cf were inserted into this aqueous solution at an interval of 1 cm, and then electrolysis was carried out at a constant current of 2 mA for 7 hours.

At this time, a black substance was deposited on the anode. The black powdery substance obtained from the anode was collected and washed three times with 1 g of distilled water 50II for 30 minutes each time.

This is followed by acetonitrile 100111.11. Washing was performed with pyridine ioog three times for 30 minutes each. This black powdery substance was immersed in 6 g of propionic acid for 24 hours, washed with methanol, and dried under reduced pressure at 60'C to obtain a black powdery substance 30no;+.

Electrical conductivity of material 4. IX 10-60-6SC
The specific surface area and pore radius distribution are each 10Tl.
12/g, 20 to 800 people, and in particular, 60% of the pores had a radius of 100 Å or more.

Battery Example The conductive material obtained in Production Example 1 above was used as a positive electrode material, and acetylene black (conductive agent) and polytetrafluoroethylene (binder) were mixed in a weight ratio of 85:10:5.
After mixing at a ratio of , the mixture was press-molded into a disk shape and used as a positive electrode.

In addition, a negative electrode was prepared by punching lithium into a predetermined size.

Next, as shown in the accompanying drawings, a negative electrode portion is formed by pressing the negative electrode 2 onto the bottom surface of the negative electrode 7 through a negative electrode current collector 8, and a negative electrode portion is formed by pressing the negative electrode 2 onto the bottom surface of the negative electrode 7 through a positive electrode current collector 6. The positive electrode part, which is in close contact with the bottom surface of the can 5, is combined with the separator 3 made of polypropylene nonwoven fabric, and an electrolytic solution made by dissolving lithium fluoroborate (electrolyte) in propylene carbonate (solvent) is used. A battery according to the present invention (toward a battery according to the present invention) was manufactured. In addition, in the figure, 4 is an insulating gasket.

Further, the conductive materials obtained in Production Examples 2, 3.4, and 5 above were used as positive electrode materials, and these, acetylene black, and polytetrafluoroethylene were mixed at an amount ratio of 85.
Batteries according to the present invention (Batteries B, C, D, and E of the present invention) were made in the same manner as Battery A of the present invention, except that the mixture was mixed at a ratio of 10:5 and pressure-molded into a disk shape, and the positive electrode was used. were prepared respectively.

On the other hand, using the conductive material obtained in Comparative Example 1 above as a positive electrode material, this was mixed with acetylene black and polytetrafluoroethylene at a weight ratio of 85:10:5, and the mixture was pressure-molded into a disk shape. A comparative battery (comparative battery F) was prepared in the same manner as battery A of the present invention except that the positive electrode was used.

The above six batteries were subjected to a charge/discharge cycle test in which they were charged at a constant current of 1 m until the battery voltage reached 4°O■, and then discharged at a constant current of 1 mA until the battery voltage reached 2.5V. I did it. As shown in Table 1 for each battery at the 20th cycle of this charge/discharge test, batteries A, B,
C, D and E Lt 7.60mAh ~ 8.90mA
Comparative battery F showed a high capacity of 5 h.
．． It was 80mAh.

Considering the reason for this, the conductive materials used as positive electrode materials in batteries A to E of the present invention are all treated with organic aliphatic carboxylic acids to increase the number of pores with large radii. Therefore, the charge/discharge capacity per unit weight was greater than that of Comparative Battery F in which an untreated conductive material was used as the positive electrode material, and it is thought that an increase in battery capacity was achieved.

Next, a charge/discharge cycle test was conducted in which the six batteries were charged at a constant current of 1 mA for 8 hours and then discharged at a constant current of 1 mA until the battery voltage reached 2.5V. The end-of-charge voltage (voltage at the end of charging) and charge-discharge capacity efficiency of each battery at the 100th cycle of this test are shown in Table 2.

Table 2 From Table 2, it can be seen that batteries A to E of the present invention have a smaller increase in battery voltage during charging and higher charge/discharge capacity efficiency than comparative battery F.

The low charge/discharge capacity efficiency of 86% for Comparative Battery F is due to the large voltage rise during charging, resulting in the decomposition of the electrolyte solvent or solute, corrosion of the battery can and current collector material, and the roughness of the conductive material itself. This is thought to be caused by deterioration, etc.

On the other hand, in the case of the battery of the present invention, since a conductive material with high electrical conductivity is used for the positive electrode, the voltage rise during charging is small, and therefore side reactions such as those mentioned above hardly occur, resulting in good battery characteristics. It is thought that it is possible to maintain this.

Although a battery using a conductive material only for the positive electrode material has been described above, it is clear that similar effects can be obtained when the conductive material according to the present invention is used for the negative electrode material or the positive and negative electrode materials.

<Effects of the Invention> According to the secondary battery of the present invention configured as described above,
The battery capacity can be increased because the charge/discharge capacity per unit weight of the electrode increases, and battery characteristics such as charge/discharge cycle life can be improved by improving the charge/discharge sound 6 efficiency due to improved electrical conductivity of the electrode. It produces such effects.

[Brief explanation of the drawing]

The accompanying drawings are cross-sectional views showing battery structures according to embodiments of the present invention. 1...Positive electrode, 2...Negative electrode, 3...Separator, 5
...Positive electrode can, 7...Negative electrode. Patent applicant Sanyo Electric Co., Ltd. Mitsubishi Chemical Industries, Ltd. Procedures? i13 official document (voluntarily submitted) 1. Indication of the case Patent Application No. 16374 of 1988 2. Name of the invention Secondary battery 3. Person making the amendment Relationship to the case Patent applicant address 2 Keihan Hondori, Moriguchi City, Osaka Prefecture Chome 18 name (1
8g) Sanyo Electric Co., Ltd. (and 1 other person) 4. Agent:
104 Address: 8-12-15, Ginza, Chuo-ku, Tokyo Telephone: Tokyo 03 (543) 003 Ei number (representative) 6, "Mercury intrusion method" in lines 8 to 9 of page 27 of the statement of contents of the amendment are corrected to "nitrogen adsorption method and mercury intrusion method, respectively."

Claims (1)

[Claims] 1. A secondary battery characterized in that a conductive material obtained by treating an oxidized polymer of an aniline compound with an organic aliphatic carboxylic acid is used as at least one of a positive electrode and a negative electrode. . 2. The above-mentioned aniline compound has the general formula ▲ mathematical formula, chemical formula, table, etc. represents an amino group or an arylamino group, and R^3 and R^4 represent a hydrogen atom, an alkyl group, or an aryl group. secondary battery. 3. Claim 1, wherein the organic aliphatic carboxylic acids are saturated aliphatic monocarboxylic acids, saturated aliphatic dicarboxylic acids, unsaturated aliphatic monocarboxylic acids, and unsaturated aliphatic dicarboxylic acids. Secondary battery listed. 4. The secondary battery according to claim 1, wherein the oxidized polymer of the aniline compound is obtained by electrochemically polymerizing the aniline compound. 5. The oxidized polymer of the aniline compound is obtained by treating the aniline compound or a salt, which is a reaction product of these compounds and an acid, with an oxidizing agent. The secondary battery according to item 1.