JPH0574196B2 - - Google Patents

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 a specific aniline polymer 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. Conductive polymers that serve as electrode materials for this type of secondary battery can be doped and undoped with dopants such as various anions and cations, which usually have little conductivity.
Doping 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 the above dopant is used as an electrolytic solution to eliminate doping and undoping. A battery that can be charged and discharged is constructed by chemically reversibly performing the process. Traditionally, such conductive polymers include polyacetylene, polypyrrole, polythiophene,
Polyaniline and the like are known, and taking polyacetylene as an example, this can be used as an electrode material for at least one of the positive electrode and the negative electrode to produce BF ₄ ^- , ClO ₄ ^- ,
Anions such as SbF ₆ ^- , PF ₆ ^- , or Li ⁺ , Na ⁺ ,
A configuration is adopted in which cations such as R ₄ -N ⁺ (R represents an alkyl group) are electrochemically reversibly doped and undoped. However, among these types of conductive polymers, polyacetylene has the disadvantage that it is very easily oxidized by oxygen in the air in doped and undoped states. For this reason, when this is used as an electrode material, it becomes important to control the electrode manufacturing environment, making the electrode manufacturing work difficult and complicated, and there are disadvantages such as poor storage stability of the electrode itself. Furthermore, when incorporated into a battery, the presence of even a small amount of oxygen or moisture can cause denaturation or decomposition, resulting in deterioration of battery characteristics, and overcharging may cause the polymer to denature or decompose. It is not very desirable as an electrode material because it has drawbacks such as a sudden increase in charging voltage, a decrease in charge/discharge efficiency, and a decrease in battery cycle life. On the other hand, among the above-mentioned various conductive polymers, polypyrrole and polyaniline have the advantage that they have better stability in air, have extremely little oxidative deterioration, and are easier to handle than the above-mentioned polyacetylene. Therefore, when polypyrrole or polyaniline is used as a battery electrode material, it is possible to obtain an electrode that is easy to produce and has a good shelf life, without the drawbacks of polyacetylene. Conventionally, such polypyrrole and polyaniline are produced by electrochemically oxidatively polymerizing pyrrole or aniline (electrolytic polymerization), or chemically oxidatively polymerizing pyrrole or aniline using an oxidizing agent, etc. ing. In the case of , polypyrrole or polyaniline is deposited in the form of a film on the electrode anode, and after the deposition is peeled off from the electrode, polypyrrole or polyaniline in the form of a film is obtained. In addition, peroxides such as potassium persulfate and ammonium persulfate are used as oxidizing agents.
Oxidation and aggregation using acids such as nitric acid, sulfuric acid, or chromic acid, Lewis acids such as ferric chloride, ruthenium chloride, tungsten chloride, or molybdenum chloride, or oxidation of ferric perchlorate in an organic solvent. The oxidative polymerization of pyrrole is carried out by using the pyrrole as an agent (Mol.Cryst.Liq.Cryst. magazine, 1985, vol. 118, pages 149-153), and powdered polypyrrole is obtained. Furthermore, it was reported by AGGreen et al. (J.
Chem. Soc. 2388 (1910)), emeraldine, which is an aniline octamer, is produced from an aqueous solution containing aniline hydrochloride using an oxidizing agent such as hydrogen peroxide. However, the manufacturing methods for conventional polypyrrole and polyaniline are complicated;
Not only does this cause high battery costs, but since polypyrrole and polyaniline are generated on the surface of the electrolytic anode, the shape and size of the polypyrrole and polyaniline obtained are restricted by the dimensions of the electrode plate. There is a disadvantage that it is difficult to mold to a certain size. Furthermore, because it is difficult to obtain a film with a uniform thickness with good reproducibility, only thin films can be used as materials for industrial batteries, which limits the battery electrode itself and the charge/discharge capacity of the battery. However, there is also the disadvantage that it is extremely difficult to increase the capacity. On the other hand, when polypyrrole or polyaniline obtained above is used, the above-mentioned disadvantages do not occur. However, polypyrrole and polyaniline have low electrical conductivity, so when a secondary battery is fabricated using them as an electrode material, the internal resistance of the battery increases and the charge/discharge reaction becomes uneven in each part of the electrode. Therefore, when charging and discharging cycles are repeated, the charging voltage tends to increase, and as the charging voltage increases, the electrolytic solution decomposes, which tends to lead to significant deterioration of battery characteristics. Furthermore, since the method uses peroxides such as hydrogen peroxide as the oxidizing agent, it is necessary to be careful about the safety of these oxidizing agents during storage and handling reactions, and they are not suitable for industrial use as electrode materials. When mass-produced, there are significant drawbacks in terms of handling and safety. Furthermore, since emeraldeine, which is an aniline octamer, has poor solvent resistance to organic solvents, it also has the disadvantage of being dissolved in an electrolytic solution when used as an electrode. Also,
Polypyrrole and polyaniline obtained by the above method have a slightly lower doping level than those obtained by the above method, so they have the disadvantage of a small battery capacity when used as a battery electrode. The present inventor has conducted research to solve the above-mentioned disadvantages by using a conductive polymer that does not have the above-mentioned conventional disadvantages as an electrode material, and has already developed an oxidizing agent made by coexisting a cupric compound and a nitrile compound. By reacting the above-mentioned conjugated compound in the presence of , a conductive material that is stable in air, has a high reaction rate, is easy to manufacture, and has high electrical conductivity. (Patent Application No. 61-215296). In addition, the conductive polymer obtained in this way has a doping level equal to or slightly higher than that obtained by the method described above, so when used as a battery electrode, the battery capacity was improved. <Problems to be solved by the invention> Among the conjugated compounds thus obtained,
Polymers of aniline compounds are conductive polymers with high electrical conductivity as mentioned above, but they have relatively high solubility in organic solvents, so when they are used as electrode materials, they do not dissolve in organic electrolytes. There is a problem in that the charging voltage sharply increases as the cycle progresses due to the reduction in the weight of the electrode due to dissolution and the formation of an inert film on the surface of the counter electrode, resulting in a decrease in charging and discharging efficiency. Not only that, the particle size of the obtained polymer is small, so the polymer has poor permeability when separating and purifying the product, which limits productivity.
Since these particles aggregate and solidify after washing and drying, there is a problem in that it is very difficult to mold the polymer into an arbitrary mold depending on the type of battery. <Means for Solving the Problems> The inventor of the present invention has conducted extensive studies on aniline polymers that do not have these problems, and has found that the intended purpose can be achieved by using the following means. As a result, this invention was completed. That is, the present invention provides a conductive material made of an aniline polymer obtained by polymerizing an aniline compound with an oxidizing agent consisting of a cupric compound and a nitrile compound, and in which the aniline compound is reacted with an acid in advance. The present invention relates to a secondary battery that uses the material as at least one of a positive electrode and a negative electrode. The cupric compound used in the present invention has, for example, the general formula CuX _n ...(1) (wherein, X is ClO ₄ ^- , BF ₄ ^- , AsF ₆ ^- , Cl ^- ,
SO ₄ ^-- , PF ₆ ^- , SbF ₆ ^- , CH ₃ C ₆ H ₄ SO ₃ ^- ,
CF ₃ SO ₃ ^- , C ₆ H ₅ SO ₃ ^- , ZrF ₆ ^-- , TiF ₆ ^-- or
represents SiF ₆ ^-- , and m represents an integer of 1 to 2. ) Examples include cupric compounds represented by: Further, the nitrile compounds used in the present invention include, for example, the general formula R(CN) _o ...(2) (wherein R is an alkyl group which may have a substituent,
Represents an alkenyl group or an aryl group, and n is 1 to 3.
represents an integer. ) Examples include nitrile compounds represented by: When producing the conductive material of the present invention, a product obtained by reacting a single or two or more different aniline compounds with an acid is used, and a single or two or more different cupric compounds are used. The compound can be reacted with an oxidizing agent consisting of a single nitrile compound or two or more different nitrile compounds. The above-mentioned aniline compounds used in the present invention include, for example, the general formula

[Formula, R ¹ and R ² 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 R ³ and R ⁴ represent a hydrogen atom, represents an alkyl group or an aryl group). The acid used in the present invention has the general formula H _a Y ... (4) (wherein, Y is ClO ₄ ^- , BF ₄ ^- , AsF ₆ ^- , Cl ^- ,
SO ₄ ^-- , PF ₆ ^- , SbF ₆ ^- , CH ₃ C ₆ H ₄ SO ₃ ^- ,
CF ₃ SO ₃ ^- , C ₆ H ₅ SO ₃ ^- , SO ₄ ^-- , ZrF ₆ ^-- , TiF ₆ ^--
or SiF ₆ ^-- , and a represents an integer of 1 to 2. ). Specifically, the cupric compound represented by the general formula (1) includes CuCl ₂ , Cu(ClO ₄ ) ₂ , Cu(BF ₄ ) ₂ , Cu
( _PF6 ) ₂ , Cu( _AsF6 ) ₂ , Cu( _SbF6 ) ₂ , Cu
(CH ₃ C ₆ H ₄ SO ₃ ) ₂ , Cu (CF ₃ CO ₃ ) ₂ , Cu
( _{C6H5SO3 ) 2} , _CuSO4 , _CuZrF6 , _{CuTiF6 ,}
CuSiF ₆ , which are usually used as compounds with water of crystallization or as aqueous solutions. In the nitrile compound represented by the general formula (2), R is a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, or vinyl group. ,
Methylvinyl group, dimethylvinyl group, ethylvinyl group, diethylvinyl group, n-propylvinyl group, n-butylvinyl group, phenylvinyl group, naphthylvinyl group, hydroxymethyl group, hydroxyethyl group, hydroxypropyl group, hydroxybutyl group, methoxy Methyl group, methoxyethyl group, methoxypropyl group, ethoxymethyl group, ethoxyethyl group, cyanomethyl group, cyanoethyle group, cyanopropyl group, cyanobutyl group, cyanopentyl group, cyanohexyl group, carboxymethyl group, cabboxyethyl group, carboxypropyl group , phenyl group, naphthyl group, tolyl group, hydroxyphenyl group, hydroxynaphthyl group, methoxyphenyl group, ethoxyphenyl group, methoxynaphthyl group, cyanophenyl group, dicyanophenyl group, cyanotolyl group, dicyanotolyl group,
Represents a cyanonaphthyl group, a carboxyphenyl group, a carboxytolyl group, etc. Specifically, such nitrile compounds include acetonitrile, n-propylnitrile, isopropionitrile, n-butyronitrile, isobutyronitrile,
tert-butyronitrile, acrylonitrile, methylacrylonitrile, ethyl acrylonitrile,
Phenyl acrylonitrile, acetone cyanohydrin, methylene cyanohydrin, ethylene cyanohydrin, propylene cyanohydrin, methoxyacetonitrile, ethoxyacetonitrile, methoxypropionitrile, malondinitrile, adiponitrile, cyanoacetic acid, cyanopropionic acid,
Cyanobutyric acid, benzonitrile, naphthonitrile,
Examples include methylbenzonitrile, hydroxybenzonitrile, phthalonitrile, tricyanobenzene, methoxybenzonitrile, carboxybenzonitrile and the like. In the aniline compound represented by the above general formula (3), R ¹ and R ² are a hydrogen atom, a methyl group, an ethyl group,
n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, methoxy group, ethoxy group, n-propoxy group, n-butoxy group, phenyl group, tolyl group,
Represents a naphthyl group, phenoxy group, methylphenoxy group, naphthoxy group, amino group, dimethylamino group, diethylamino group, phenylamino group, diphenylamino group, methylphenylamino group, phenylnaphthylamino group, and R ³ and R ⁴ are hydrogen atoms. , methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, phenyl group, tolyl group, and naphthyl group. Specific examples of such aniline compounds include aniline, methylaniline, ethylaniline, n-propylaniline, isopropylaniline, n-butylaniline, methoxyaniline, ethoxyaniline, n-propoxyaniline, phenylaniline, and toluyl. Aniline, naphthylaniline, phenoxyaniline, methylphenoxyaniline, naphthoxyaniline, aminoaniline,
Examples include dimethylaminoaniline, diethylaminoaniline, phenylaminoaniline, diphenylaminoaniline, methylphenylaminoaniline, and phenylnaphthylaminoaniline. Specifically, the acid represented by the above general formula (4) is
HClO ₄ , HBF ₄ , HAsF ₆ , HCl, H ₂ SO ₄ , HPF ₆ ,
_{HSbF6 , CH3C6H4SO3H , CF3SO3H , _}
These are C ₆ H ₅ SO ₃ H, H ₂ TiF ₆ , and H ₂ SiF ₆ , and these are usually dissolved in an organic solvent such as alcohol, ether, or nitrile, or used as an aqueous solution. When the aniline compound and the oxidizing agent are reacted, it can be carried out in the presence of a conductive material.
Such a conductive material is used in powder or granular form, and specifically includes acetylene black, activated carbon, metal powder, inorganic oxide, etc., and acetylene black is preferably used. The amount used is 0.001 to 100 times the amount of the above aniline compound (weight ratio)
and preferably 0.005 to 50 times (weight ratio). The amount of the cupric compound represented by general formula (1) is:
The aniline compound represented by the general formula (3) is converted to the general formula (4).
For 1 mole of the acid treated with
It is 0.01 to 100 times the mole, preferably 0.5 to 50 times the mole. In addition, the nitrile compound represented by general formula (2) is
It is used in combination with a cupric compound, and examples of how to use it include the following methods. (1) A nitrile compound and a cupric compound are allowed to coexist in advance, and then treated with an aniline compound and an acid are allowed to act. (2) A cupric compound is applied to a system in which a nitrile compound and an aniline compound and those treated with an acid coexist. (3) A nitrile compound is applied to the system in which the aniline compound and the acid-treated material coexist with the cupric compound. (4) A system in which a cupric compound and a nitrile compound coexist is applied to a system in which a nitrile compound and a compound treated with an aniline compound and an acid coexist. (5) A reaction product of a cupric compound and a nitrile compound is isolated in advance and treated with an aniline compound and an acid. The amount of the nitrile compound represented by the general formula (2) to be used is 0.01 to 10,000 times, preferably 0.1 to 1,000 times, per mol 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, it can be used as an arbitrary solvent, such as water, alcoholic solvents such as methanol and ethanol, tetrahydrofuran, dioxane, benzene, and toluene. , dichloromethane, dichloroethane, acetic acid, and other common organic solvents can be used. The amount of the acid represented by general formula (4) to be used is 0.01 to 10 times, preferably 0.05 to 5 times, by mole per mole of the aniline compound. The reaction temperature is -50°C to 150°C, preferably -20°C to 100°C. The reaction time is related to the reaction temperature, but is usually 0.5 to 200 hours, preferably 1.0 to 100 hours.
It's time. The reaction product is a dark brown to black powdery substance, and in the reaction in the presence of the above solvent, after the reaction is completed and the solvent is removed by a conventional method, in the present invention,
By washing and purifying the reaction product several times with a liquid nitrile compound, for example an organic solvent such as acetonitrile or propionitrile, and dissolving and removing by-product cuprous compounds, a product with higher conductivity can be obtained. It is preferable because you can get things. 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. Generally, those with a molecular weight of 10,000 or more are used, and specific examples include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-etrafluoroethylene copolymer, polytetrafluoroethylene, polytrifluoroethylene, and polydifluoroethylene. , tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polytrifluorochloroethylene, polyvinylidene fluoride, tetrafluoroethylene-ethylene copolymer, chlorotrifluoride Examples include fluoroethylene-ethylene copolymer, polyamide, polyester, polycarbonate, and modified polyolefin. In addition, the conductive member is made of a material that does not dissolve even after repeated charging and discharging, such as stainless steel,
There is no particular restriction as long as it is made of metal such as gold, platinum, nickel, copper, molybdenum, titanium, etc., carbon, carbon fiber, etc., but lightweight and highly conductive materials are particularly preferred. 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 the thermoplastic resin and conductive member added is 0.02 to 1000 parts by weight of the thermoplastic resin and 2 to 1000 parts by weight of the conductive member per 100 parts by weight of the reaction product (conductive material).
Preferably, 100 parts by weight are used. 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,
For other electrodes, metals, metal oxides, other inorganic compounds, and even known conductive polymers, organic compounds, organometallic compounds, etc. 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 electrode material for the negative electrode, the electronegativity of the metal that makes up the negative electrode is
It is preferable to use 1.6 or less, and examples of such metals include Li, Na, K, Mg, Al, and alloys thereof, with Li and Li alloys being preferred. On the other hand, as the electrolytic solution used in the secondary battery of the present invention, 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. Also, anion is
BF ₄ ^- , ClO ₄ ^- , PF ₆ ^- , AsF ₆ ^- , CF ₃ SO ₃ ^- , I ^- ,
Examples include Br ^- , Cl ^- , F ^- and the like. Specific examples of such electrolytes include lithium tetrafluoroborate (LiBF ₄ ), lithium perchlorate (LiClO ₄ ), lithium hexafluorophosphate (LiPF ₆ ), and lithium tetrachloroaluminate (LiAlCl ₄ ). , tetraethylammonium tetrafluoroborate (Et ₄ NBF ₄ ), tetran-perchlorate
Examples include, but are not limited to, butylammonium (nBu ₄ NClO ₄ ), lithium trifluoromethanesulfonate (LiCF ₃ SO ₃ ), lithium iodide (LiI), lithium bromide (LiBr), etc. . For example, if a battery is constructed using the conductive material of the present invention for the positive and negative electrodes and an electrolyte solution made by dissolving LiBF ₄ as the electrolyte, during charging, the conductive material in the positive electrode will be exposed to the electrolyte solution. BF ₄ ^- but
Further, the conductive materials in the negative electrode are each doped with Li ⁺ in the electrolyte. On the other hand, during discharge, BF ₄ ^- and Li ⁺ doped into the positive and negative electrodes are released into the electrolyte, respectively. The organic solvent for dissolving the electrolyte is preferably one with a high dielectric constant and aprotic properties, such as nitrile, carbonate, ether, nitro compound, amide, sulfur-containing compound, chlorinated hydrocarbon, ketone,
Ester 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,
Examples include 4-dioxone, nitromethane, N,N-dimethylformamide, dimethylsulfoxide, sulfolane, 1,2-dichloroethane, γ-butyrolactone, 1,2-dimethoxyethane, methyl phosphate, ethyl phosphate, etc. It is not limited to these. The concentration of the electrolyte of the present invention is usually 0.001
It is used in an amount of ~10 mol/, preferably 0.1-3 mol/. 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> The above conductive material not only has excellent oxidation resistance, is easy to manufacture, and has high electrical conductivity, but also has low solubility in organic solvents, and has good transient properties of products from the reaction solution. Can be easily molded into any shape. Therefore, when an electrode is made using this conductive material, it is possible to prevent a decrease in the weight of the electrode due to dissolution and the formation of an inert film on the surface of the counter electrode, improving charge/discharge efficiency and cycle life. Since it can be molded into any desired shape, electrodes and batteries with predetermined charging and discharging performance can be easily made smaller or thinner. Furthermore, since this conductive material has a high doping level, a large battery capacity can be maintained even when the battery is made smaller or thinner. <Example> The present invention will be specifically described below with reference to Examples. Manufacturing example of conductive material 1 18.6g of aniline in round bottom flask
(0.2 mol) was added to this solution under ice-cooling (0-5℃) while stirring under a nitrogen atmosphere.
41.8 g (0.2 mol) of HBF ₄ aqueous solution was added dropwise over 10 minutes. As the mixture was added, heat generation was observed, and the reaction solution became cloudy, and a powdery solid was precipitated in the reaction solution to form a slurry. After continuing stirring for 30 minutes, 45% Cu( _BF4 ) ₂ prepared in advance at room temperature (15-20 °C) was added to this reaction solution.
316.2g (0.6mol) of aqueous solution and 300g of acetonitrile
The mixture was added dropwise over 15 minutes. A slight heat generation was observed during the dropwise addition, and the reaction solution immediately turned black, and a powdery solid was precipitated in the reaction solution, forming a slurry-like state. After continuing stirring for 2 hours, the mixture was left at room temperature overnight. The reaction product was then separated to obtain a black powdery substance mixed with white crystals. When this was washed 4 times with 600 ml of acetonitrile, it was easy to carry out a filtration operation after washing, and the white crystalline substance was removed by this operation. Rest temperature 60
Drying under reduced pressure at °C yielded 17.43 g of a black powdery substance that was hardly soluble in organic solvents. Elemental analysis of this black powdery substance showed that
Obtained C50.05%, H3.68%, N10.04%, F24.56%,
Assuming carbon is 6, C _6.0 , H _5.29 , N _1.03 ,
I got the equivalent of F _18.6 . Furthermore, as a result of measuring the electrical conductivity of this black powder substance using the two-terminal method, it was found to be 1.2×10 ^-1 Scm ^-1 , indicating that it is a conductive material with conductivity in the semiconductor region. . The electrical conductivity was measured as follows. First, the black powder obtained by the above treatment was ground sufficiently finely in a mortar, and then pressure-molded (5 tons/cm ² ) into a disk shape with a diameter of 10 mm. At this time, pulverization and molding could be performed extremely easily. Next, this disk sample was sandwiched between two copper cylinders of the same size, a 1.2 kg load 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). The electrical conductivity of the disk sample was measured by . For comparison, the reaction and washing were carried out in the same manner as in Production Example 1 above, except that the HBF ₄ solution was not used, and the resulting polymer had poor permeability and was difficult to wash with an organic solvent. . Then, when drying was carried out under reduced pressure at a temperature of 60° C., 6.7 g of a black powdery substance which was considerably soluble in an organic solvent was obtained. In addition, it was extremely difficult to crush and pressurize this powder. From the above results, by using an aniline compound that has been reacted with an acid in advance to react with the oxidizing agent, a reaction product that is difficult to dissolve in organic solvents, has good permeability, and has good moldability can be obtained. It was confirmed that Manufacturing example 2 of conductive material 1.8g of acetylene black was coexisted in the reaction system,
The experiment was otherwise conducted in the same manner as in Production Example 1, and 20.0 g of a black powdery substance that was hardly soluble in organic solvents was obtained. This material had good pulverization and moldability, and an electrical conductivity of 1.6×10 ^-1 Scm ^-1 . Manufacturing example 3 of conductive material: 21.2 g of ortho-toluidine instead of aniline,
An experiment was conducted in the same manner as in Production Example 1 above using 19.7 g of a 37% HCl aqueous solution instead of the HBF ₄ aqueous solution.
20.0 g of a black powdery substance was obtained which was hardly soluble in organic solvents, had good permeability, and had good moldability.
From the elemental analysis of the obtained black powdery substance, assuming that carbon is 7, C _7.0 , H _7.20 , M _1.01 , Cl _0.30 , F _0.04
I got something equivalent to . Production Examples 4 to 13 of Conductive Materials The reaction products of various aniline compounds and various acids were subjected to the same reaction as in Production Example 1 above using an oxidizing agent consisting of various cupric compounds and nitrile compounds. I did it. Table 1 shows the results of the examination of the obtained dark brown to black powder. In addition, when the reaction is carried out using a solvent other than nitrile compounds,
The solvents used are also shown in Table 1.

【table】

[Table] Battery Examples The conductive material obtained in Production Example 1 above was used as the positive electrode material, and the acetylene block (conductive agent) and polytetrafluoroethylene (binder) were mixed in a weight ratio of 85:10:5. After mixing in the same proportions, 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 FIG. 1, the negative electrode 2 is crimped onto the bottom surface of the negative electrode can 5 via the negative electrode current collector 7, and the positive electrode 1 obtained above is connected to the positive electrode current collector 6. and a positive electrode part made by closely contacting the bottom surface of the positive electrode can 4 through the separator 3 made of polypropylene nonwoven fabric. A battery according to the present invention (product A of the present invention) was produced using an electrolytic solution dissolved in a solvent). In addition, 8 in FIG. 1 is an insulating gasket. All of the above operations were performed in a dry box with an argon atmosphere. Further, a battery according to the present invention (present invention product B) was produced in the same manner as the present invention product A, except that the pressure-molded conductive material obtained in Production Example 2 was used as a positive electrode. Further, the conductive material obtained in Production Example 3 above was used as a positive electrode material, and the weight ratio of this and acetylene black and polytetrafluoroethylene was 85:10:5.
A battery according to the present invention (Product C of the present invention) was produced in the same manner as Product A of the present invention, except that the positive electrode was prepared by mixing the mixture at a ratio of 1 and press-molding it into a disk shape. On the other hand, a conductive material prepared in the same manner as in Production Example 1 above was used as the positive electrode material, except that the HBF ₄ (hydroboric acid) aqueous solution was not used, and this was mixed with acetylene black and polytetrafluoroethylene at a weight ratio of 85:1. A comparative battery (comparative product D) was prepared in the same manner as inventive product A except that a positive electrode was prepared by mixing the mixture at a ratio of 5:5 and press-molding it into a disk shape. For the above four batteries, at a current of 1 mA, 5
After charging for an hour, the battery voltage increases with a current of 1mA.
Cycle changes in charge/discharge efficiency (%) of each battery were investigated when repeated charge/discharge cycles were performed in which the battery was discharged to 2.5V. The results are shown in FIG. From the same figure, comparative product D shows a rapid decrease in charging and discharging efficiency after 60 cycles, whereas products A to C of the present invention only show higher charging and discharging efficiency than comparative product D throughout the entire cycle. It can be seen that the battery continues to maintain a high charge/discharge efficiency of nearly 100% even after 90 cycles. In addition, the charging and discharging efficiency of products A to C of the present invention at the 90th cycle was 100, respectively.
%, whereas in the case of comparative product D it is only 55%.
It was hot. Therefore, when Comparative Product D was disassembled and investigated after the 90th cycle, it was confirmed that the electrolyte was colored and polyaniline was eluted into the electrolyte. On the other hand, the products A to C of the present invention were also disassembled and investigated.
No electrolyte coloring on the negative electrode surface was observed. According to this investigation, the reason why the cycle characteristics of Comparative Product D are so poor is that the polyaniline, which is the positive electrode material, dissolves in the electrolyte as the cycle progresses, resulting in a decrease in the weight of the positive electrode and a buildup on the surface of the negative electrode. This is thought to be because an inert film is formed, the battery voltage increases at the end of charging, and the electrolyte decomposes and deteriorates.
In the case of products A to C of the present invention, since the cathode material hardly dissolves in the electrolyte, such a phenomenon of weight loss of the cathode or the formation of an inert film on the surface of the anode does not occur, and therefore good cycle characteristics are achieved. It seems that they have come to maintain it. FIG. 3 shows the time-dependent changes in battery voltage during charging and discharging at the 90th cycle. In the figure, the solid line represents the voltage change during charging, and the dotted line represents the voltage change during discharging. From FIG. 3, it can be seen that the products A to C of the present invention do not have a sudden rise in voltage during charging, and the flatness of the discharge voltage is much better than that of the comparative product D, and the discharge voltage is stable. Although the above description has been made using the conductive material of the present invention only in the positive electrode, it is clear that similar effects can be obtained when the conductive material of the present invention is used in both the negative electrode and the positive electrode. <Effects of the Invention> According to the secondary battery of the present invention configured as described above, the electrode material is a conductive material that has low solubility in organic solvents and can be easily molded into any shape. Since it was used in the electrolyte, there is no reduction in electrode weight or sudden increase in charging voltage during the cycle due to dissolution in the electrolyte, improving charge/discharge efficiency and cycle life. The effect is that it can be easily made thinner.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing the battery structure of an example of the present invention, Fig. 2 is a graph showing the cycle characteristics of the inventive product and the comparative product, and Fig. 3 is a graph showing the cycle characteristics of the inventive product and the comparative product. It is a graph showing a change in battery voltage over time. 1...Positive electrode, 2...Negative electrode, 4...Positive electrode can, 5...
... Negative electrode can, 6... Positive electrode current collector, 7... Negative electrode current collector.

Claims (1)

[Scope of Claims] 1. An aniline polymer obtained by polymerizing an aniline compound with an oxidizing agent consisting of a cupric compound and a nitrile compound, and in which the aniline compound has been reacted with an acid in advance. A secondary battery characterized in that a conductive material is used for at least one of a positive electrode and a negative electrode. 2 The cupric compound has the general formula CuX _n ...(1) (wherein, X is ClO ₄ ^- , BF ₄ ^- , AsF ₆ ^- , Cl ^- ,
SO ₄ ^-- , PF ₆ ^- , SbF ₆ ^- , CH ₃ C ₆ H ₄ SO ₃ ^- ,
CF ₃ SO ₃ ^- , C ₆ H ₅ SO ₃ ^- , ZrF ₆ ^-- , TiF ₆ ^-- or
represents SiF ₆ ^-- , and m represents an integer of 1 to 2. ) The secondary battery according to claim 1, which is a cupric compound represented by: 3 The nitrile compound has the general formula R(CN) _o ...(2) (wherein R is an alkyl group which may have a substituent,
Represents an alkenyl group or an aryl group, and n is 1 to 3.
represents an integer. ) The secondary battery according to claim 1, which is a nitrile compound represented by: ⁴ The aniline compound has the ^general formula ³ and ^R4 represent a hydrogen atom, an alkyl group, or an aryl group.) The secondary battery according to claim 1, wherein the secondary battery is an aniline compound represented by the following formula. 5 The acid has the general formula H _a Y...(4) (wherein Y is ClO ₄ ^- , BF ₄ ^- , AsF ₆ ^- , Cl ^- ,
SO ₄ ^-- , PF ₆ ^- , SbF ₆ ^- , CH ₃ C ₆ H ₄ SO ₃ ^- ,
CF ₃ SO ₃ ^- , C ₆ H ₅ SO ₃ ^- , ZrF ₆ ^-- , TiF ₆ ^-- or
represents SiF ₆ ^-- , and a represents an integer of 1 to 2. ) The secondary battery according to claim 1, wherein the secondary battery is an acid represented by: