JP2003017062A - Energy storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an energy storage medium with a large capacity and high cycle characteristics. SOLUTION: This energy storage medium uses an electrode comprising an N-oxide (nitrogen condensation heterocyclic) polymer having a building block represented in formula 1, a material containing an electrolyte containing an anion containing a sulfur atom, and a material containing an electrolyte containing a cation acting as a counter ion of the anion. (Optional two of a to h are carbon atoms participating in bonding between repeating units, at least one of them represents an N→O group, and the remaining represent a C atom, a CH group, a N atom, or an N→O group; polymerization degree n is at least 5; R<1> and R<2> independently represent a H atom, a halogen atom, a hydroxyl group, a carboxyl group, a sulfone group, a sulfate group, a nitro group, a cyano group, an alkyl group, an aryl group, an alkoxyl group, an amino group, an alkyl thio group, and an aryl thio group, etc.).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an energy storage medium used as an energy storage medium. In particular,
The present invention relates to a high capacity energy storage medium that is chemically and electrically stable and has excellent heat resistance.

[0002]

2. Description of the Related Art The use of conductive polymer materials for electrodes of energy storage media and electrode surfaces has been studied. For example, conductive polymers such as polyacetylene and polypyridine have been studied as electrode materials. Generally, when imparting conductivity to these π-conjugated polymer materials, it is necessary to perform electrical or chemical oxidation (p doping) or reduction (n doping). In this case, with the result that the doping material itself chemically reacts again with the conductive polymer material to exchange electrons with the conductive material, which significantly impairs the electrical conductivity characteristics, and as a result, when the conductive material is used as the electrode material, However, there are problems such as low capacity and low cycle performance of the.

In many cases, the stability of n-doped compounds is poor, and as a result, when these conductive materials are used as electrode materials, their characteristics are deteriorated.

Recently, for example, J. Electroche
m. As disclosed in Soc, 140, 2498, 1993, it is disclosed that polyphenylquinoxaline performs a redox reaction as shown in the following (formula (I)) in concentrated hydrochloric acid aqueous solution. In this case, chlorine ion (C
l ⁻ ) is used as a dopant.

[0005]

[Chemical 8]

[0006] (wherein, the degree of polymerization n of at least 5, X ^- is Cl ^- represents a) further, J. Electrochem. Soc, 14
5, 1193, 1998, it is disclosed that the polyphenylquinoxaline exhibits conductivity even in a strong acid, and charge / discharge is performed by a mechanism similar to the reaction mechanism represented by the formula (I).

[0007]

However, when polyphenylquinoxaline is used as the conductive material as described above, the polyphenylquinoxaline has a large molecular weight per unit unit, that is, one monomer, and also has the above formula (I). As shown in the reaction mechanism shown in (1), since chlorine ions are used as a dopant, the number of reaction electrons is as small as 2 electrons, and the problem is that the capacity per volume or weight is small. Further, the solubility of the polymer itself in the electrolytic solution has been pointed out as a cause of the deterioration of the characteristics of the energy medium.

It has been pointed out that polymers such as polyacetylene and polypyridine are deteriorated in characteristics of energy medium due to solubility of the polymer itself in an electrolytic solution. That is, it has been pointed out that the stability to the electrolytic solution is extremely poor.

The present invention is to overcome the above problems and provide an energy medium having excellent stability.

[0010]

That is, the present invention is based on the formula (1)

[0011]

[Chemical 9]

(In the formula, any two of a, b, c, d, e, f, g and h are carbon atoms involved in the bond between repeating units, and at least one is an N → O group. And the rest are each independently a carbon atom, a CH group, a nitrogen atom or N → O.
Group, the maximum total number of N → O groups contained in a, b, c, d is 2, the maximum total number of nitrogen atoms is 2, and is contained in e, f, g, h The maximum number of N → O groups represented is 2, the total number of nitrogen atoms is 2, the degree of polymerization n is represented by at least 5, and R ¹ and R ² are each independently a hydrogen atom, a halogen atom, It represents a hydroxyl group, a carboxyl group, a sulfone group, a sulfuric acid group, a nitro group, a cyano group, an alkyl group, an aryl group, an alkoxyl group, an amino group, an alkylthio group and an arylthio group. ) N-oxidized poly having a structural unit represented by (nitrogen-containing condensed heterocycle)
A polymer, an electrolyte containing an anion containing a sulfur atom,
The present invention relates to an energy storage medium characterized by using an electrode made of a material containing an electrolyte containing a cation serving as the counter ion.

Further, the present invention provides the formula (2)

[0014]

[Chemical 10]

(In the formula, any two of a, b, c, d, e, f, g and h represent a carbon atom involved in a bond between repeating units, and at least one of them is an N → O group. And the rest represent carbon atoms, CH groups, nitrogen atoms or N → O groups, and
The maximum total number of N → O groups contained in b, c, and d is 2,
The maximum number of nitrogen atoms represents 2, and e, f,
The maximum total number of N → O groups contained in g and h is 2, the total number of nitrogen atoms is 2, and o, p, q, r, s,
Any two of t, u and v represent a carbon atom involved in a bond between repeating units, and the rest are each independently,
Represents a carbon atom, a CH group or a nitrogen atom, and is o, p, q, r
The maximum total number of nitrogen atoms contained in 2 represents 2, the maximum total number of nitrogen atoms contained in s, t, u, v represents 2, and the degree of polymerization l + m represents an integer of at least 5, R ¹ ,
R ² , R ³ and R ⁴ are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a sulfone group, a sulfuric acid group, a nitro group, a cyano group, an alkyl group, an aryl group, an alkoxyl group, an amino group, an alkylthio group. Represents a group and an arylthio group. ) An electrode made of a material containing an N-oxidized poly (nitrogen-containing condensed heterocycle) polymer represented by the formula (1), an electrolyte containing an anion containing a sulfur atom, and an electrolyte containing a cation serving as its counter ion. The present invention relates to an energy storage medium characterized by using.

The polymer of the above formula (1) is a polymer mainly containing a repeating unit in which a nitrogen atom of a nitrogen-containing condensed heterocycle is oxidized, and the polymer of the formula (2) is a nitrogen-containing condensed polymer. It is a copolymer composed of a repeating unit in which a nitrogen atom of a heterocycle is oxidized and a repeating unit in which a nitrogen atom of a nitrogen-containing condensed heterocycle is not oxidized. In the copolymer of the formula (2), the repeating unit in which the nitrogen atom of the nitrogen-containing condensed heterocycle is oxidized and the repeating unit in which the nitrogen atom of the nitrogen-containing condensed heterocycle is not oxidized are randomly copolymerized. It is polymerized.

The above-mentioned N-oxidized poly (nitrogen-containing condensed heterocycle) polymer is an anion containing the above-mentioned sulfur atom,
Alternatively, the counter cation reacts with the nitrogen atom of the N-oxidized poly (nitrogen-containing condensed heterocycle) polymer, paying attention to the fact that a stable redox reaction proceeds between the negative electrode and the positive electrode, and stability is improved. It has been possible to obtain an excellent energy storage medium. The present invention will be described in detail below.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an energy storage medium according to an embodiment of the present invention and a manufacturing method thereof will be described with reference to the drawings. FIG. 1 is a schematic sectional view of an energy storage medium according to an embodiment of the present invention.

The energy storage medium according to the embodiment of the present invention is a secondary energy storage medium that can be repeatedly used by charging with an external power source, and as shown in FIG. 5, a negative electrode 2 and a positive electrode 3 having different properties are installed on one surface of the negative electrode 2.
And the positive electrode 3 are installed so as to face each other with the separator 4 in between.

The negative electrode 2 is not particularly limited, but it is formed on the surface of the electrode and contains an N-oxidized poly (nitrogen-containing condensed heterocyclic) polymer as a conductive active material and an anion containing a sulfur atom as a dopant. It is formed from a film containing an electrolyte and an electrolyte containing a cation which is its counter ion. Generally, the membrane is between 5 and 800 μm, but is preferably controlled between 50 and 200 μm.

The positive electrode 3 is not particularly limited, but can be made of a conductive material such as an N-oxidized poly (nitrogen-containing condensed heterocycle) polymer or polyaniline derivative.

Further, the separator 4 is formed by impregnating it with an electrolytic solution in which the above-mentioned electrolyte is dissolved, or uses a solid electrolyte or a gel electrolyte. The material generally used as the separator is not particularly limited, but examples thereof include polymethylmethacrylate, polyacrylonitrile, polyethylene oxide, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, and the like.

The electrolytic solution is a solvent in which an electrolyte having no electron conductivity but ionic conductivity is dissolved, and water or an organic solvent (for example, propylene carbonate, ethylene carbonate, etc.) is used. Each of the current collectors 1 and 5 is made of a sheet-shaped metal conductor, and is made of a flat plate or a grid structure of copper or aluminum.

Formula (1) used as an electrode material

[0025]

[Chemical 11]

An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer having a structural unit represented by the following formula, wherein a, b, and
Any two of c, d, e, f, g and h are carbon atoms involved in the bond between repeating units, and at least 1
One represents an N → O group, the rest represent a carbon atom, a CH group, a nitrogen atom or an N → O group, and the maximum total number of N → O groups contained in a, b, c, d is 2, The maximum total number of atoms is 2, the maximum total number of N → O groups contained in e, f, g, and h is 2, the total number of nitrogen atoms is 2, and the degree of polymerization is n. Represents at least 5, preferably 5 or more and 10 or more from the viewpoint of mechanical strength, solvent resistance, and processability thereof.
0000 or less, and more preferably 100 or more and 10,000 or less is the suggested amount.

R ¹ and R ² are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a sulfone group, a sulfuric acid group, a nitro group, a cyano group, an alkyl group, an aryl group, an alkoxyl group, an amino group, an alkylthio group. And an arylthio group, wherein the alkyl group preferably has 1 to 20 carbon atoms, and particularly preferably 1 to 5 carbon atoms. Specific examples of the monovalent hydrocarbon group include alkyl such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and decyl group. Group, cyclopentyl group, cycloalkyl group such as cyclohexyl group, bicycloalkyl group such as bicyclohexyl group, vinyl group, 1-propenyl group, 2-propenyl group,
Isopropenyl group, 1-methyl-2-propenyl group, 1
Alternatively, an alkenyl group such as a 2 or 3-butenyl group and a hexenyl group can be mentioned. Further, as an aryl group, an aryl group such as a phenyl group, a xylyl group, a tolyl group, a biphenyl group and a naphthyl group, an aralkyl group such as a benzyl group, a phenylethyl group and a phenylcyclohexyl group, and hydrogen of these monovalent hydrocarbon groups. Examples thereof include those in which some or all of the atoms have been replaced with halogen atoms, hydroxyl groups, alkoxy groups and the like.

Equation (2)

[0029]

[Chemical 12]

An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer having a structural unit represented by the following formula:
Any two of c, d, e, f, g and h represent a carbon atom involved in a bond between repeating units, and at least 1
One is an N → O group, the rest are each independently a carbon atom, CH
Group, nitrogen atom or N → O group, the maximum total number of N → O groups contained in a, b, c, d is 2, the maximum total number of nitrogen atoms is 2, and e , F, g, h, the maximum total number of N → O groups is 2, the total number of nitrogen atoms is 2, and o, p, q, r, s, t, u and v Among them, any two represent a carbon atom involved in a bond between repeating units, the rest independently represent a carbon atom, a CH group or a nitrogen atom, and each of the nitrogen atoms contained in o, p, q and r. The maximum total number is 2, and the maximum total number of nitrogen atoms contained in s, t, u, and v is 2, and the degree of polymerization l + m is an integer of at least 5, but its mechanical strength and solvent resistance. , And more preferably 5 or more and 10 from the viewpoint of workability.
0000 or less, and more preferably 100 or more and 10,000 or less is the suggested amount.

R ¹ , R ² , R ³ and R ⁴ are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a sulfone group, a sulfuric acid group, a nitro group, a cyano group, an alkyl group, an aryl group or an alkoxyl group. Group, amino group, alkylthio group, arylthio group and the like.

The alkyl group has preferably 1 to 20 carbon atoms, and more preferably 1 to 5 carbon atoms. Specific examples of the monovalent hydrocarbon group include alkyl such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and decyl group. Group, cyclopentyl group, cycloalkyl group such as cyclohexyl group, bicycloalkyl group such as bicyclohexyl group, vinyl group, 1-propenyl group, 2-propenyl group, isopropenyl group, 1-methyl-2-propenyl group, 1 or Examples thereof include alkenyl groups such as 2 or 3-butenyl groups and hexenyl groups. Further, as the aryl group, an aryl group such as a phenyl group, a xylyl group, a tolyl group, a biphenyl group, a naphthyl group, an aralkyl group such as a benzyl group, a phenylethyl group, a phenylcyclohexyl group, etc., and hydrogen of these monovalent hydrocarbon groups. Examples thereof include those in which some or all of the atoms have been replaced with halogen atoms, hydroxyl groups, alkoxy groups and the like.

As a subgroup of the N-oxidized poly (nitrogen-containing condensed heterocycle) polymer represented by the formula (1),
N-oxidized poly (quinolinediyl) of the following formula (1a)
Polymer, N-oxidized poly (quinoxalinediyl) polymer of (1b-1) and (1b-2), N-oxidized poly (naphthyridinediyl) polymer of (1c-1) and (1c-2) There is.

[0034]

[Chemical 13]

In the formula, the degrees of polymerization n ₁ , n ₂ , n ₃ , n ₄ and n ₅
Represents an integer of at least 5, but preferably 5 or more and 100,000 or less, more preferably 100 or more and 100 or more from the viewpoint of mechanical strength, solvent resistance, and processability thereof.
A quantity of 00 or less is proposed. R ¹ and R ² are the same as above.

As a subgroup of the N-oxidized poly (nitrogen-containing condensed heterocycle) polymer represented by the above formula (2), the formula (2) is an N-oxidized compound represented by the following formula (2a). Poly (quinolinediyl) copolymer, (2b-1) and (2
b-2) N-oxidized poly (quinoxalinediyl)
There are copolymers, N-oxidized poly (naphthyridinediyl) copolymers of (2c-1) and (2c-2).

[0037]

[Chemical 14]

In the formula, the degree of polymerization l ₁ + m ₁ , l ₂ + m ₂ , l ₃ +
m ₃ , l ₄ + m ₄ and l ₅ + m ₅ represent an integer of at least 5, but preferably 5 or more and 100000 or less, more preferably from the viewpoint of mechanical strength, solvent resistance, and processability thereof. The recommended amount is 100 or more and 10000 or less. R ¹ , R ² , R ³ and R ⁴ have the same meanings as described above.

The above-mentioned polymer used in the present invention has the formula (3)

[0040]

[Chemical 15]

(Where o, p, q, r, s, t, u,
v, R ¹ and R ² have the same meanings as described above, and the degree of polymerization x represents at least 5. ) A poly (nitrogen-containing condensed heterocycle) polymer containing a divalent group represented by the formula), especially the following formulas (3a), (3b) and (3c)

[0042]

[Chemical 16]

(In the formula, the polymerization degrees x ₁ , x ₂ and x ₃ represent at least 5, and R ¹ and R ² have the same meanings as described above.) As a constitutional unit. Containing poly (quinolinediyl), poly (quinoxalinediyl) or poly (naphthyridinediyl) polymers containing suitable peroxides such as peracetic acid (hydrogen peroxide and glacial acetic acid), persulfuric acid,
It was reacted with m-chloroperbenzoic acid to convert the ring nitrogen atom into N-
It is produced by oxidization. In this reaction, the peroxide to be used is not limited to the above-mentioned examples, and the formula (1) of the polymer used in the present invention can be obtained by devising the type, equivalent or reaction conditions of the peroxide to be used. And formula (2), or formula (1a) and formula (2a), formula (1b-1) and formula (2b-1), formula (1b-2) and formula (2b-2), formula (1c-1). ) And the formula (2c-1), and the formula (1c-2) and the formula (2c-2) can be separately manufactured.

As another method for producing the polymer used in the present invention, the following formula (4)

[0045]

[Chemical 17]

(In the formula, X and Y each represent a halogen atom, and among a, b, c, d, e, f, g and h,
Any two are carbon atoms bonded to the halogen atom,
At least one represents an N → O group, the rest independently represent a carbon atom, a CH group or a nitrogen atom, and a, b,
The maximum total number of N → O groups contained in c and d is 2, the maximum total number of nitrogen atoms is 2, and e, f, g, h
The maximum total number of N → O groups contained in 2 is 2, the maximum total number of nitrogen atoms is 2, and R ¹ and R ² have the same meanings as described above. ), Particularly quinoline oxide, quinoxaline oxide, quinoxaline dioxide, 1,5-naphthyridine oxide, or 1,5-naphthyridine dioxide represented by the formula (4a) in which any two hydrogen atoms are substituted with halogen atoms. ), Formula (4b-1), formula (4
b-2), formula (4c-1) or formula (4c-2)

[0047]

[Chemical 18]

(Wherein X and Y each represent a halogen atom, and R ¹ and R ² have the same meanings as described above), and a method of reacting the dihalide compound with a zero-valent nickel compound can be mentioned. it can. That is, it is obtained by adding an equimolar amount or more of a zero-valent nickel compound in an organic solvent to the above dihalide compound, reacting them, and dehalogenating. Suitable reaction temperatures are room temperature to about 8
The temperature is between 0 ° C and the reaction is completed in about 24 hours. As the organic solvent, for example, N, N-dimethylformamide, acetonitrile, toluene, tetrahydrofuran or the like can be applied.

The polymer used in the present invention is a dihalide compound represented by the above formula (4), especially quinoline oxide, quinoxaline oxide, quinoxaline dioxide, 1,5-naphthyridine oxide or 1,5-naphthyridine dioxide. Of the above formula (4a) and formula (4b-1) in which hydrogen atoms at any two positions of are substituted with halogen atoms,
Formula (4b-2), Formula (4c-1) or Formula (4c-2)
It can also be produced by electrolytically reducing the dihalide compound represented by: in the presence of a nickel compound.
That is, when the dihalide compound is subjected to an electrolytic reduction reaction in the presence of a divalent nickel compound, an N-oxidized poly (nitrogen-containing condensed heterocycle) polymer can be obtained by a dehalogenation reaction.

As described above, the electrolyte used in the energy storage medium according to the embodiment of the present invention is an electrolyte containing an anion containing a sulfur atom and a cation serving as its counter ion. . Although the electrolyte is not particularly specified here, for example, sulfuric acid as an inorganic acid, benzenesulfonic acid as an organic acid, alkylbenzenesulfonic acid, camphorsulfonic acid, 5-sulfosalicylic acid, p-toluenesulfonic acid, methanesulfonic acid,
Examples include trifluoromethane sulfonate ion, butane sulfonate ion, trichlorobenzene sulfonate ion, naphthalene sulfonate ion, perfluorobutane sulfonate ion, perfluorooctane sulfonate ion, polystyrene sulfonate ion, and polyvinyl sulfonate ion.

The counter ion is not particularly limited, but is not limited to, proton, alkali metal ion (lithium ion, sodium ion, potassium ion), alkaline earth metal (magnesium ion, Examples thereof include calcium ion, barium ion), aluminum ion, iron ion, nickel ion, and tetramethylammonium ion.

Next, a method of manufacturing an energy storage medium using the resin material will be described. The energy medium actually used is shown in FIG. The negative electrode 2 is formed as follows, but the method is not particularly limited. First, carbon was added as a conductivity-imparting agent to an N-oxidized poly (nitrogen-containing condensed heterocycle) polymer, and this was added to D
It is dissolved or dispersed in MF and NMP to form a varnish. It is effective to use a ball mill for varnishing. The obtained varnish is applied on the copper current collector 1 by a doctor blade method or the like and dried. After being sufficiently dried, pressure is applied using a pressing machine to adjust the film thickness. The positive electrode 3 is not particularly limited, but polyaniline is used as the amine-based conductive polymer, carbon is added as a conductivity-providing agent to this, and DMF or NMP slurry in which a binder polymer is mixed is used in a ball mill. To create. The film formation can be performed in the same manner as the negative electrode. The doping of these electrodes is not particularly limited, but can be chemically performed using trifluoromethanesulfonic acid or the like. Next, a separator prepared in advance is dipped in an electrolytic solution containing a similar doping agent, and after sufficiently impregnated, the positive electrode and the negative electrode prepared previously are bonded together via this separator to obtain an energy storage medium. You can

In addition to the above, the energy medium shown in FIG. 2 may be used. Carbon is added to the N-oxidized poly (nitrogen-containing condensed heterocycle) polymer as a conductivity-imparting agent,
This is dissolved or dispersed in DMF and NMP to form a varnish. It is effective to use a ball mill for varnishing. The obtained varnish is applied on the copper current collector 5 by the doctor blade method and dried. Using this varnish, a positive electrode and a negative electrode are prepared, and although not particularly limited thereto, chemically performed using trifluoromethanesulfonic acid, and then the positive electrode is passed through a separator sufficiently containing a doping agent. It is possible to obtain an energy storage medium by laminating the negative electrodes.

Next, examples of the energy storage medium according to the present embodiment will be shown together with comparative examples, and the energy storage medium according to the present invention will be specifically described. The energy storage medium obtained here was subjected to a charging test at a constant current.

[0055]

[Example] Example 1 As the negative electrode shown in FIG.

[0056]

[Chemical 19]

Poly (naphthyridine-1) represented by
-Oxide-2,6-diyl) polymer (n = 185) was used for the positive electrode 2 with the formula (7).

[0058]

[Chemical 20]

Polyaniline represented by (number average molecular weight 1
2000) was used. In addition, the negative electrode 1 and the positive electrode 2
Trifluoromethanesulfonic acid was used as a dopant.

The polyaniline represented by the formula (7) was mixed with a conductivity-imparting agent (carbon) in a weight ratio of 3: 1, and a binder (polyvinylidene fluoride-hexafluoropropylene) was added thereto in an amount of 6 wt%. To prepare a slurry. The obtained slurry is stirred by a ball mill and then coated on one side of the current collector 5 by the doctor blade method. The obtained thin film is sufficiently dried and then pressed by a press to adjust the film thickness. Drying was performed at 100 ° C. under reduced pressure.
The film thickness was about 80 μm. Next, a negative electrode was prepared using the same method. Here, the mixing ratio of the poly (naphthyridine-1-oxide-2,6-diyl) polymer and the conductivity-imparting agent (carbon) was 2: 1 and the film thickness was about 100 μm.
An aqueous solution of trifluoromethanesulfonic acid was used as an electrolytic solution, and the negative electrode 2 and the positive electrode 3 were chemically doped. Subsequently, the above-mentioned electrodes were bonded together via the separator 4 impregnated with the electrolytic solution to obtain an energy storage medium.

The battery performance was as follows. First, the obtained energy storage medium was charged to 0.9 V at a constant current of 0.5 mA / cm 2. The obtained capacity was 102 Wh / kg per weight of the negative electrode active material. Even in the cycle characteristics, the initial capacity (in this case, 102 Wh / k
The number of cycles until 80% of g) was 2300. As for the capacity storage characteristics, the capacity after 30 days at 25 ° C. was 76%.

Example 2 The poly (naphthyridine-1-oxide-2,6-diyl) polymer represented by the formula (6) used in Example 1 was used as the positive and negative electrode active materials, and sulfuric acid was used as the dopant. Was used to create an energy storage medium.

The electrode was in accordance with the method for preparing a negative electrode shown in Example 1. Further, an energy storage medium was obtained by pasting together with a separator impregnated with the electrolytic solution. The completed capacitor was charged at a constant current of 0.5 mA / cm ² . As a result, the obtained capacity was 19 Wh / kg per negative electrode active material. Also in the cycle characteristics, the number of cycles until reaching 80% of the initial capacity was 5000 times.

Comparative Example 1 In the case of using hydrochloric acid as a dopant, Example 1
The same experiment was performed. As a result, when the energy storage medium was charged to 0.9 V at a constant current of 0.5 mA / cm ² , the capacity was 55 Wh / kg per weight of the negative electrode active material.
Also in the cycle characteristics, the number of cycles until reaching 80% of the initial capacity was 800 times.

Comparative Example 2 Polyaniline (number average molecular weight 1200
0) was used as the positive and negative electrode active materials, and the same experiment as in Example 2 was performed. As a result, the obtained capacity was 9.4 wh / kg per negative electrode active material, and the cycle number was 1200 before the capacity reached 80% of the initial capacity.
It was once.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an energy storage medium according to a mode of Example 1 of the present invention.

FIG. 2 is a schematic sectional view of an energy storage medium according to a form of Example 2 of the present invention.

[Explanation of symbols]

1 Current collector 2 Negative electrode 3 positive electrode 4 separator 5 Current collector

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4J002 CM021 DG046 EV256 FD206                 4J032 BA12 BC03 BD02                 5H029 AJ05 AK16 AL16 AM02 AM07                       BJ04 DJ09 EJ13 HJ02                 5H050 AA07 BA15 CA22 CA25 CB22                       CB25 HA02

Claims (9)

[Claims] 1. Formula (1): (In the formula, any two of a, b, c, d, e, f, g and h are carbon atoms involved in the bond between repeating units, and at least one is an N → O group, and the rest are Each independently represent a carbon atom, a CH group, a nitrogen atom or an N → O group,
The maximum total number of N → O groups contained in a, b, c, d is 2
The maximum total number of nitrogen atoms is 2, and e,
The maximum total number of N → O groups contained in f, g, and h is 2,
The total number of nitrogen atoms is 2, the degree of polymerization n is represented by at least 5, and R ¹ and R ² are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a sulfone group, a sulfate group, a nitro group. Represents a cyano group, an alkyl group, an aryl group, an alkoxyl group, an amino group, an alkylthio group and an arylthio group. ) An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer having a structural unit represented by the formula (1), an electrolyte containing an anion containing a sulfur atom, and an electrolyte containing a cation serving as its counter ion. An energy storage medium characterized by using an electrode made of a material. 2. Formula (2): (In the formula, any two of a, b, c, d, e, f, g and h represent a carbon atom involved in a bond between repeating units, and at least one is an N → O group, and the rest are Is a carbon atom, C
Represents a H group, a nitrogen atom or an N → O group, the maximum total number of N → O groups contained in a, b, c, d is 2, the maximum total number of nitrogen atoms is 2, and The maximum total number of N → O groups contained in e, f, g and h is 2, the total number of nitrogen atoms is 2, and o, p, q, r, s, t, u and v Among them, any two represent a carbon atom involved in a bond between repeating units, the rest independently represent a carbon atom, a CH group or a nitrogen atom, and each of the nitrogen atoms contained in o, p, q and r The maximum total number is 2, and the maximum total number of nitrogen atoms contained in s, t, u, v is 2, and the polymerization degree l + m represents an integer of at least 5, R ¹ , R ² , R ³ , And R ⁴ are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a sulfone group, a sulfuric acid group, a nitro group,
Cyano group, alkyl group, aryl group, alkoxyl group,
It represents an amino group, an alkylthio group and an arylthio group. ) An electrode made of a material containing an N-oxidized poly (nitrogen-containing condensed heterocycle) polymer represented by the formula (1), an electrolyte containing an anion containing a sulfur atom, and an electrolyte containing a cation serving as its counter ion. An energy storage medium characterized by using. 3. An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer of the formula (1) has the following formulas (1a), (1b-1),
(1b-2), (1c-1) or (1c-2) (Wherein the polymerization degrees n ₁ , n ₂ , n ₃ , n ₄ and n ₅ represent at least 5, and R ¹ and R ² have the same meanings as described above). . 4. An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer of the formula (2) has the following formulas (2a), (2b-1),
(2b-2), (2c-1) or (2c-2) (In the formula, the degree of polymerization l ₁ + m ₁ , l ₂ + m ₂ , l ₃ + m ₃ , l ₄ +
m ₅ represents at least 5, and R ¹ , R ² , R ³ and R ⁴ have the same meanings as described above. ) Is an energy storage medium according to claim 2. 5. An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer is represented by the formula (3): (In the formula, o, p, q, r, s, t, u, v and the substituent R
¹ , R ² has the same meaning as described above, and the degree of polymerization x represents at least 5. ), A poly (nitrogen-containing condensed heterocycle) polymer containing a divalent group as a constitutional unit is reacted with a peroxide to N-oxidize the nitrogen atom in the ring to obtain an N-oxidized poly ( A nitrogen-containing condensed heterocycle) polymer.
An energy storage medium according to claim 4. 6. An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer is represented by the formula (4): (In the formula, X and Y each represent a halogen atom, and a,
Any one of b, c, d, e, f, g and h is a carbon atom bonded to the halogen atom, at least one is an N → O group, and the rest are each independently a carbon atom, C
Represents a H group or a nitrogen atom, the maximum total number of N → O groups contained in a, b, c, d is 2, the maximum total number of nitrogen atoms is 2, and e, f, g, The maximum total number of N → O groups contained in h is 2, the maximum total number of nitrogen atoms is 2, and R ¹ and R ² are each independently a hydrogen atom, a halogen atom, a hydroxyl group or a carboxyl group. , A sulfone group, a sulfuric acid group, a nitro group, a cyano group, an alkyl group, an aryl group, an alkoxyl group, an amino group, an alkylthio group and an arylthio group. The energy storage medium according to any one of claims 1 to 4, which is an N-oxidized polypolymer obtained by reacting the dihalide compound represented by the formula (4) with a zero-valent nickel compound. 7. An N-oxidized poly (nitrogen-containing condensed heterocycle) polymer obtained by electrolytically reducing a dihalide compound represented by the above formula (4) in the presence of a zero-valent nickel compound. The energy storage medium according to any one of claims 1 to 4, which is a polypolymer. 8. The poly (nitrogen-containing condensed heterocycle) polymer of the formula (3) is represented by the following formulas (3a), (3b) and (3c): The energy storage medium according to claim 5, wherein R ¹ and R ² are the same as those in formula (3), and the degrees of polymerization x ₁ , x ₂ and x ₃ represent at least 5. 9. The formula (1) or (2) on the surface of the current collector.
An electrode is formed by applying a film having an N-oxidized poly (nitrogen-containing condensed heterocycle) polymer represented by, and includes an electrolyte containing an anion containing a sulfur atom and a cation serving as a counter ion thereof. A method for producing an energy storage medium, which comprises doping an N-oxidized poly (nitrogen-containing condensed heterocycle) polymer in the electrode with a solution containing an electrolyte.