JP2003109594A - Electrode material, manufacturing method of the same, electrode for battery using the same, and battery using the electrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode material having high electrical conductivity, high redox reaction speed, and stability against the redox reaction, compared with the conventional electrode material. SOLUTION: An electrode material has a polymerized compound containing sulfur on the surface of carbonaceous material, and an electrode using the electrode material and a cell using the electrode is provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electrode material, a battery electrode obtained from the same, and a high capacity using the same.
The present invention relates to a battery having high energy density, high power density and excellent cycle life.

[0002]

2. Description of the Related Art In recent years, new type secondary batteries such as nickel / hydrogen batteries and Li-ion batteries have recently been rapidly mounted in small portable devices due to their high energy density, and have shown rapid growth. In particular, when a lithium ion battery using a graphite negative electrode / LiCoO ₂ negative electrode is used, the weight and size of the device are further reduced, and it is becoming the mainstream of secondary batteries. For the purpose of further increasing the energy density, for example, LiNiO ₂ , Li
Mn ₂ O ₄ , metal oxides such as MoS ₂ and metal sulfides are used for the positive electrode, lithium, lithium alloys, carbon materials capable of absorbing and releasing lithium ions and inorganic compounds are used for the negative electrode, and lithium ions using an organic electrolyte are used. Many batteries have been studied. "J. Electrochem. Soc., Vol. 138, No. 3, p. 665, 1991", Li.
A lithium battery using Mn ₂ O ₄ or LiNiO ₂ as a positive electrode has been reported.

Also, there are many reports on batteries using a conductive polymer as an electrode active material. For example, a lithium secondary battery using a polyaniline as a positive electrode is described in "27th Battery Conference, 3A05L and 3A06L, 1986." As reported by Bridgestone / Seiko-
Marketed as a coin-type battery for backup power supply.

However, the Li-based electrode materials that have been studied so far have reached the limit of the number of Li reaction electrons per unit weight, and it is difficult to achieve a dramatic increase in energy density. ing. From such a viewpoint, European Patent 415856 proposes to use an organic sulfur compound as an electrode material.

The organic sulfur compound charges and discharges by utilizing the oxidation-reduction reaction of sulfur, has a remarkably large theoretical energy density per unit weight, and has an oxidation-reduction potential of about 3 V with respect to Li. As a positive electrode material for the above-mentioned high energy density Li battery, it has been vigorously studied in recent years.

However, in the case of the organic sulfur compound positive electrode, its redox reaction is slow and the extraction current becomes small at room temperature, so that there is a problem that it can be used only at a high temperature around 100 ° C.

On the other hand, Japanese Patent Laid-Open No. 2000-24805
No. 4, the aromatic polymer having a dithiazolium ring has a large electrochemical redox capacity and can be applied to an electrode for a secondary battery, and the processability, reversibility and redox reaction rate of the above organic sulfur compound are high. It is described that it is improved. However, although this material has improved workability and redox reactivity, it is still inadequate, its electrical conductivity is inadequate, it can operate only at low current at room temperature, and it is easily dissolved in the electrolyte. In addition, there is a problem that the capacity sharply decreases in the charge / discharge cycle of the battery.

On the other hand, the Chemistry Letter
s (p. 946, 2000) describes a material for battery electrodes in which a dithiazoline ring is introduced into an aromatic conjugated polymer to improve the redox reactivity and processability of the above organic sulfur compound. However, this material also has a problem that the electron conductivity is not sufficiently improved, a sufficient redox reaction cannot be performed at room temperature, and when used as a battery, it can operate only at a high temperature.

As described above, the electrode material using the organic sulfur compound whose main purpose is to increase the energy density is
Many problems still remain.

[0010]

SUMMARY OF THE INVENTION The present invention is based on the conventional Li
It is an object of the present invention to provide a new electrode material containing an organic sulfur-based compound, which is superior in energy density and the like to a system-based electrode material, and a manufacturing method thereof.

Another object of the present invention is to provide a battery electrode using the electrode material as one of the constituent elements, and further a battery using the electrode.

[0012]

Means for Solving the Problems The present inventors have made extensive studies in view of the above problems. As a result, the new electrode material, which is characterized in that the polymer of the compound containing sulfur is formed on the surface of the carbon material, has a higher electric conductivity than the conventional electrode material and a redox reaction rate. The inventors have found that they are large and have excellent stability against redox reactions, and completed the present invention.

Further, it is possible to provide an electrode using the electrode material, and further a battery using the electrode, which is excellent in energy density and current characteristics, and which is excellent in safety, reliability and high-speed current characteristics. We have found this and completed the present invention.

That is, the present invention (I) is an electrode material characterized in that a polymer of a compound containing sulfur is formed on the surface of a carbon material.

The present invention (II) is also a process for producing an electrode material of the present invention (I), which comprises forming a polymer of a compound having sulfur in the presence of a carbon material.

Furthermore, the present invention (III) is an electrode for a battery, which comprises the electrode material of the present invention (I) as one of the constituent elements.

Furthermore, the present invention (IV) is a battery characterized by including the battery electrode of the present invention (III) as one of the constituent elements.

Further, the present invention is based on, for example, the following [1] to [2].
0].

[1] An electrode material characterized in that a polymer of a compound containing sulfur is formed on the surface of a carbon material.

[2] A polymer of a compound containing sulfur is
The electrode material according to [1], which is a polymer containing at least one dithiazoline ring and / or dithiazolium ring.

[3] A polymer of a compound containing sulfur is
The electrode material according to any one of [1] and [2], which is a polymer represented by the following general formula (1).

General formula (1)

[0023]

[Chemical 3]

(Wherein R ¹ is hydrogen, halogen, nitro group,
It represents an organic group having 1 to 20 carbon atoms which may have a hetero atom, and a plurality of benzene rings may be independently bonded.
n is an integer. )

[4] A polymer of a compound containing sulfur is
The electrode material as described in [1] or [2], which is a polymer represented by the following general formula (2).

General formula (2)

[0027]

[Chemical 4]

(In the formula, R ² is hydrogen, halogen, a nitro group,
It represents an organic group having 1 to 20 carbon atoms which may have a hetero atom, and a plurality of benzene rings may be independently bonded.
m is an integer. X represents an anion. )

[5] Any one of [1] to [4], wherein the carbon material is at least one selected from the group consisting of carbon blacks, activated carbons, carbon fibers, and graphites. The electrode material as described in 1.

[6] The carbon material is a fibrous carbon material having an aspect ratio of 5 or more [1] to
The electrode material according to any one of [5].

[7] The content of the carbon material is from 1% by mass to
It is characterized by being in the range of 50% by mass [1]-
The electrode material according to any one of [6].

[8] Volume conductivity at 25 ° C. is 0.1 S /
The electrode material according to any one of [1] to [7], which is cm or more.

[0033]

[9] A polymer of a compound having sulfur is formed in the presence of a carbon material [1]
~ The method for producing an electrode material according to any one of [8].

[10] reacting a compound having an isothiocyanate group with a (S-alkyl) thiourea group in the presence of a carbon material to form a polymer of a compound having sulfur on the surface of the carbon material. [1]
~ The method for producing an electrode material according to any one of [8].

[11] In the presence of a carbon material, a compound having a thioamide group is subjected to oxidative condensation polymerization to form a polymer of a compound having sulfur on the surface of the carbon material [1] to The method for producing an electrode material according to any one of [8].

[12] A battery electrode comprising the electrode material according to any one of [1] to [8] as one of the constituent elements.

[13] The battery electrode according to [12], which is capable of performing a redox reaction by absorbing and releasing Li ions.

[14] The battery electrode according to any one of [12] and [13], which has an electrode density of 0.8 g / cm ³ or more.

[15] A battery comprising the battery electrode according to any one of [12] to [14] as one of the constituent elements.

[16] The battery electrode according to any one of [12] to [14] is included as one of the constituent elements, and Li
A non-aqueous secondary battery, which is capable of charge / discharge reaction by ion absorption / desorption and uses a non-aqueous electrolyte.

[17] The non-aqueous secondary battery according to [16], wherein the non-aqueous electrolyte is at least one selected from the group consisting of a solid electrolyte and a gel electrolyte.

[18] The solid electrolyte or gel electrolyte is
The non-aqueous secondary battery according to [17], which is an electrolyte obtained by reacting a mixture of a polymerizable compound having a double bond and a Li ion conductive substance.

[19] For the solid electrolyte or gel electrolyte,
The non-aqueous secondary battery according to any one of [17] and [18], which contains at least one kind of non-electroconductive powder.

[20] The non-electron conductive powder is 0.00
The non-aqueous secondary battery according to [19], which is an inorganic powder having a particle size in the range of 1 μm to 10 μm.

[0045]

BEST MODE FOR CARRYING OUT THE INVENTION The specific contents of the present invention will be described in detail below. 1-1. Sulfur-containing polymer One of the preferable examples of the sulfur-containing polymer which is the main constituent element of the electrode material of the present invention is a polymer containing a dithiazoline ring, more preferably a polymer represented by the following general formula (1). It is united.

General formula (1)

[0047]

[Chemical 5]

(Wherein R ¹ is hydrogen, halogen, nitro group,
It represents an organic group having 1 to 20 carbon atoms which may have a hetero atom, and a plurality of benzene rings may be independently bonded.
n is an integer. )

In the general formula (1), R ¹ is, for example, hydrogen, an alkyl group such as a methyl group, an ethyl group or a propyl group,
An alkenyl group such as an ethenyl group, a 2-propenyl group, a 1,3-butadienyl group, a 4-methoxy-2-butenyl group,
Ethynyl group, alkynyl group such as 2-propynyl group, phenyl group, thienyl group, prolyl group, 4-methoxyphenyl group, 3-trifluoromethylphenyl group, naphthyl group, aryl group such as 3-methylthienyl group, fluorine, Halogen group such as chlorine, trifluoromethyl group, methoxy group,
Alkoxy group such as ethoxy group, acetyl group, benzoyl group, carboxylic acid group, carboxylic acid ester group, nitro group,
The sulfonic acid group, sulfonic acid ester group, etc. can be increased.

The degree of polymerization n is not particularly limited, but is usually in the range of 2 or more and 1,000,000 or less, preferably 5
The above range is 10,000 or less.

The polymer represented by the general formula (1) undergoes a thiol / disulfide reversible reaction represented by the reaction formula (1), and a battery using the same as an electrode material has a high capacity, a high voltage and a high energy density. Is. Reaction formula (1)

[0052]

[Chemical 6]

Another preferable example of the sulfur-containing polymer is a polymer containing a dithiazolium ring, more preferably a polymer represented by the following general formula (2).

General formula (2)

[0055]

[Chemical 7]

(In the formula, R ² is hydrogen, halogen, a nitro group,
It represents an organic group having 1 to 20 carbon atoms which may have a hetero atom, and a plurality of benzene rings may be independently bonded.
m is an integer. X represents halogen. )

In the general formula (2), R ² is, for example, hydrogen, an alkyl group such as a methyl group, an ethyl group or a propyl group,
Alkenyl groups such as ethenyl group, 2-propenyl group, 1,3-butadienyl group, 4-methoxy-2-butenyl group, etc., alkynyl groups such as ethynyl group, 2-propynyl group, etc.
Aryl groups such as phenyl group, thienyl group, prolyl group, 4-methoxyphenyl group, 3-trifluoromethylphenyl group, naphthyl group, 3-methylthienyl group, fluorine,
Increase halogen groups such as chlorine, alkoxy groups such as trifluoromethyl group, methoxy group, ethoxy group, acetyl group, benzoyl group, carboxylic acid group, carboxylic acid ester group, nitro group, sulfonic acid group, sulfonic acid ester group, etc. be able to.

X in the general formula (2) is a counter anion and is not particularly limited as long as it is an ion which is stable to redox.
Specifically, for example, perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion and the like are preferable. The degree of polymerization m is not particularly limited, but is usually 2 or more and 1,000,
000 or less, preferably 5 or more and 10,000
The range is 0 or less.

The polymer represented by the formula (2) has the reaction formula (2)
It is considered that the three-electron redox reaction as shown in (1) occurs reversibly, and a battery using this as an electrode material is preferable because of its high capacity and high energy density. Reaction formula (2)

[0060]

[Chemical 8]

General formula (1) or general formula (2) of the present invention
The conductive carbon material to be composited with the sulfur-containing polymer represented by is not particularly limited, but one having high conductivity, large specific surface area and small particle size is preferable. However, if the specific surface area is too large and / or the particle size is too small, the activity becomes high, side reactions are likely to occur, and the bulk becomes high, and the energy density per volume (Wh / m ³ ) may become small.

Therefore, the preferable ranges of these are that the conductivity is 0.1 S / cm or more at room temperature and the specific surface area is BET.
The (N ₂ ) method is 1 m ² / g or more and 5000 m ² / g or less, and the average particle size is 0.1 μm or more and 30 μm or less.

Specific examples of these conductive carbon materials include carbon blacks such as Ketjen black and acetylene black, activated carbons such as coconut shell activated carbon, carbon fibers such as vapor grown carbon fibers and carbon fibers, natural graphite, and artificial carbon. Examples thereof include graphites such as graphite, but are not limited thereto. 1-3. Polymerization and composite of polymer and conductive carbon material

The electrode material of the present invention (I) can be produced by combining a carbon material and a polymer of a compound containing sulfur. The compounding with the carbon material is performed by polymerizing a compound containing sulfur in the presence of carbon powder. Thus, the surface of the conductive carbon material powder is coated with the sulfur-containing polymer, and an electrode having a higher conductivity and a higher redox rate than a system in which the sulfur-containing polymer and the conductive carbon material are mechanically mixed later. A material powder can be obtained.

The polymer electrode material represented by the general formula (1) can be obtained, for example, by the route of the scheme (1).

Scheme (1)

[0067]

[Chemical 9]

Here, it is preferable that R ¹ is the above-mentioned substituent, and R ³ is an alkyl group, which is a benzyl group or an allyl group which is easily eliminated.

When a compound having an isothiocyanate group and an S-alkylthiourea group or a thiourea group is reacted in a solvent in the presence of a conductive carbon material, a polymer having an (S-alkyl) thioburet coats the surface of the carbon material. The obtained electrode material can be obtained.

If this is electrochemically oxidized or chemically oxidized (bromine oxidation, iodine oxidation, hydrogen peroxide oxidation, etc.)
An electrode material composed of a carbon material and a polymer having a dithiazoline ring can be obtained.

The reaction temperature is not particularly limited. Generally, the preferred range varies depending on the type of the monomer used and the solvent and cannot be unconditionally limited, but is usually in the range of 50 ° C to 150 ° C, and more preferably in the range of 60 ° C to 100 ° C.

The solvent used is not particularly limited as long as the monomer used is easily dissolved and does not react. Further, a solvent having a high affinity with the conductive carbon material is preferable. Specifically, for example, N, N-dimethylformamide (hereinafter abbreviated as "DMF"), a nitrogen-containing polar solvent such as N-methylpyrrolidone, tetrahydrofuran (hereinafter abbreviated as "THF"), 1,2-dimethoxy. Examples thereof include ethers such as ethane (hereinafter abbreviated as “DME”), triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether, but are not limited thereto.

The polymer represented by the general formula (2) having a dithiazolium ring can be obtained, for example, by the route of scheme (2).

Scheme (2)

[0075]

[Chemical 10]

That is, it can be obtained by oxidative polymerization using an aromatic compound having thioamide groups at both ends as a monomer and under strong acid with an oxidizing agent such as hydrogen peroxide. In this case, if the reaction is performed in the presence of the conductive carbon material, the sulfur-containing polymer can be formed on the surface of the conductive carbon material.

As the solvent to be used, for example, carboxylic acid such as formic acid and acetic acid and strong acid, perchloric acid, tetrafluoroboric acid and the like can be used, but the solvent is not limited thereto.

Examples of the oxidizing agent include hydrogen peroxide and m-
Chloropersonzoic acid, bromine, iodine, ammonium persulfate and the like can be used, but are not limited thereto.

In either scheme (1) or scheme (2), stirring conditions are important for polymerization in the presence of a carbon material. That is, when the stirring speed is low, the composite of the polymer and the conductive carbon material tends to be nonuniform, which is not preferable.

If the stirring speed is too fast, the structure of the conductive carbon material may be broken before the polymer is formed on the surface of the conductive carbon material, which is not preferable.

Therefore, the stirring speed during polymerization is 100.
The range of rpm (per minute) or more and 500 rpm or less is preferable, and the range of 150 rpm or more and 400 rpm or less is particularly preferable.

If the stirring speed is too slow, the conductive carbon material is not sufficiently dispersed or the secondary particles are not crushed sufficiently, resulting in non-uniform polymer coating. Further, if the stirring speed is too fast, the conductive carbon material is crushed too finely, and the polymer coating reduces the exposed portion of the conductive carbon material, and the electrical conductivity as an electrode material is not sufficient, which is preferable. Absent.

As the composite amount of the conductive carbon material, the content ratio of the carbon material in the obtained electrode material is 1% by mass to 5%.
The range of 0 mass% is preferable, the range of 5 mass% to 40 mass% is more preferable, and the range of 8 mass% to 30 mass% is particularly preferable.

If the amount of the conductive carbon material added is too small,
The amount of the polymer coated is too large and the conductivity may decrease, which is not preferable. When the amount of the conductive carbon material added is too large, the volume becomes high and it becomes difficult to mold, and the amount of the sulfur-containing polymer that is the electrode active material in the electrode material becomes small, and the battery per volume and weight as the electrode material. It is not preferable because the capacity may decrease.

2. Electrode There is no particular limitation on the method for molding the electrode material of the sulfur-containing polymer of the present invention and the conductive carbon material into an electrode, and any known method can be used.

As a specific example of the molding method, for example, a solvent in which the sulfur-containing polymer is dissolved or swollen is mixed with the present electrode material, and in some cases, another electrode binder is added to prepare a paste. By coating / drying this paste on the current collector and, if necessary, pressurizing, it is possible to obtain an electrode uniformly molded on the current collector.

As another specific example of the method, the powder of the present electrode material is embedded in a mold by a dry method, and after adding another electrode binder in some cases, the electrode material powder is embedded in a mold and heated by a pressure press to be self-supporting. The electrode can be easily molded.

In the latter method, the polymer is softened by heating and acts as a binder, so that another binder is unnecessary or can be made in a very small amount. Generally, the electrode binder is non-conductive and not only lowers the conductivity of the entire electrode but also lowers the activity as an electrode.
A method of performing pressure press molding without any other binder is preferable.

The current collector used for the electrode of the present invention is not particularly limited as long as it is in the form of an electron conductive sheet, and various metal foils, various conductive carbon material sheets such as graphite sheets, conductive rubber sheets and the like. However, since a corrosive electrolyte material such as an acidic aqueous solution is often used, it is preferable to use a metal foil, a conductive carbon material sheet, or a conductive rubber sheet having resistance to these.

Other electrode binders that can be added during electrode molding are polyvinylidene fluoride (hereinafter referred to as "P
Abbreviated as "VDF". ) Or Teflon (registered trademark), a fluorine resin such as polyethylene, a polyolefin resin such as polyethylene, or an aromatic resin such as polyimide.

The structure of the battery of the present invention is shown by taking a sheet type as shown in FIG. 1 as an example. Basically, it has a laminated structure of positive electrode / electrolyte + separator / negative electrode.

3. BATTERY STRUCTURE AND MANUFACTURING METHOD 3-1. Positive electrode A positive electrode uses an electrode obtained by molding the electrode material of the sulfur-containing polymer of the present invention and a conductive carbon material.

3-2. Negative Electrode The negative electrode to be combined with the positive electrode containing the sulfur-containing polymer / conductive carbon material is not particularly limited in the present invention. It suffices that it is active in various redox reactions and its redox potential is lower than the redox potential of the sulfur-containing polymer. In particular, if it is active in oxidation-reduction due to insertion and release of Li, it can be used in a Li-based battery having a high energy density, which is preferable. As such a material, by using an alkali metal, an alkali metal alloy, a carbon material, or a material having a low redox potential with an alkali metal ion such as a metal oxide or a metal chalcogenide as a carrier, a high voltage and a high capacity can be obtained. It is preferable because a battery can be obtained. Among such negative electrode active materials, lithium metal or lithium alloys such as lithium / aluminum metal, lithium / lead alloy, and lithium / antimony alloy are particularly preferable because they have the lowest redox potential. Further, the carbon material is particularly preferable in that it has a low redox potential when it absorbs lithium ions, and is stable and safe. Materials capable of inserting and extracting lithium ions include inorganic compounds such as tin oxide, natural graphite, artificial graphite, vapor phase graphite, petroleum coke, coal coke, pitch-based carbon, fullerenes such as polyacene, C ₆₀ and C _70. Etc.

3-3. Electrolyte The electrolyte of the present invention may contain a solvent and an electrolyte salt, and optionally a polymer. 3-3-1 Solvent As the solvent of the present invention, a compound having a high dielectric constant, low viscosity, high solubility of an electrolyte salt, a boiling point of 70 ° C. or higher, and a wide electrochemical stability range is preferable. In particular, an organic solvent (non-aqueous organic solvent) having a water content lower than that of the aqueous solution is preferable because of its wide range of electrochemical stability.

Specific examples of such a solvent include oligoethers such as triethylene glycol methyl ether and tetraethylene glycol dimethyl ether; carbonates such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate and vinylene carbonate. Esters; Aliphatic esters such as methyl propionate and methyl formate; Aromatic nitriles such as benzonitrile and tolunitrile; Amides such as dimethylformamide; Sulfoxides such as dimethyl sulfoxide; Lactones such as γ-butyrolactone; Sulfolane Examples thereof include sulfur compounds such as N-methylpyrrolidone, N-vinylpyrrolidone, and phosphoric acid esters, but are not limited thereto.

Of these, carbonates, aliphatic esters and ethers are preferable, and carbonates are particularly preferable. These may be used alone or as a mixed solvent in which two or more kinds are mixed. In the case of using a polymer, the amount of the solvent can be contained in an amount of 200% by mass or more based on the polymer in view of electric characteristics such as ionic conductivity and viscosity, but in the range of 300% by mass to 1500% by mass. It is preferably contained.

3-3-2 Polymer and Polymerizable Compound for Obtaining It By using a polymer material for the electrolyte of the present invention, a polymer solid electrolyte and / or a polymer gel electrolyte can be obtained. In that case, a method of directly mixing the polymer with another electrolyte material, and a method of polymerizing the compound by mixing the polymerizable compound and then polymerizing the compound are included. The latter method is preferable in terms of process and cost when the electrolyte is combined with another material such as an electrode or formed into an element.

As the polymer or polymerizable compound that can be used, a compound having a high dielectric constant, low viscosity, high solubility of an electrolyte salt and a wide electrochemical stability range is preferable. Further, it is important for the polymerizable compound to have the property that it is easily polymerized.

The polymer or polymerizable compound that can be used from such a viewpoint is, for example,

(A) Represented by the general formula (3) (meta)
Polymer or polymerizable compound having acrylate-based polymerizable functional group, general formula (3)

[0101]

[Chemical 11]

(In the formula, R ⁴ represents a hydrogen atom or an alkyl group having 10 or less carbon atoms and may have a linear, branched or cyclic structure.)

(B) A polymer or polymerizable compound having a urethane (meth) acrylate-based polymerizable functional group represented by the general formula (4), the general formula (4)

[0104]

[Chemical 12]

(In the formula, R ⁵ represents a hydrogen atom or an alkyl group having 10 or less carbon atoms, and may have a linear, branched or cyclic structure. R ⁶ contains a hetero atom. A group having 1 to 10 carbon atoms may have a linear, branched or cyclic structure.
p represents 0 or an integer of 1 to 10. ), Or

(C) Polymer or polymerizable compound represented by general formula (5) having a urea (meth) acrylate-based polymerizable functional group, general formula (5)

[0107]

[Chemical 13]

(In the formula, R ⁷ represents a hydrogen atom or an alkyl group having 10 or less carbon atoms, and may have a linear, branched or cyclic structure. R ⁸ contains a hetero atom. A group having 1 to 10 carbon atoms may have a linear, branched or cyclic structure.
q represents 0 or an integer of 1 to 10. ) Etc. can be mentioned.

Among the polymerizable functional groups represented by the general formula (3), the general formula (4) or the general formula (5), a polymer or a polymerizable compound having at least one functional group is plural in the same molecule. It may contain a polymerizable functional group represented by the general formula (3), the general formula (4) or the general formula (5). In that case, R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , p, and q in each polymerizable functional group in the same molecule may be the same or different.

Of the polymerizable functional groups represented by the general formula (3), the general formula (4) or the general formula (5), among the polymers or polymerizable compounds having at least one functional group, the general formula ( 4) or a compound having at least one polymerizable functional group represented by the general formula (5) is preferable. Among them, R in the polymerizable functional group represented by the general formula (4) or the general formula (5)
A polymerizable compound having a polymerizable functional group in which ⁶ and / or R ⁸ is at least one of oxyalkylene, fluorocarbon, oxyfluorocarbon and / or carbonate group is particularly preferable.

More specifically, these are compounds having a (meth) acrylate structure and a moiety containing an oxyalkylene, fluorocarbon, oxyfluorocarbon and / or carbonate group. The (meth) acrylate structure can be crosslinked or form a main chain by a polymerization reaction, and also includes oxyalkylene, fluorocarbon,
A portion containing an oxyfluorocarbon or a carbonate group can be crosslinked and / or form a side chain structure after polymerization.

In these structures, the hetero atom can increase the dielectric constant, accelerate the ionization of the electrolyte salt, improve the ionic conductivity of the electrolyte, and accelerate the curability in radical polymerization. As a result, the residual double bond is very small even if the amount of the polymerization initiator added is small, and the polymerization is completely advanced, which is preferable.

The polymer or polymerizable compound having at least one functional group among the polymerizable functional groups represented by the general formula (3), the general formula (4) or the general formula (5) can be prepared by a conventionally known method. It can be manufactured. For example, easily by reacting a (meth) acrylic acid chloride represented by the general formula (6) or an isocyanate compound represented by the general formula (7) with a compound having a hydroxyl group or an amino group at the terminal. Can be obtained.

General formula (6)

[0115]

[Chemical 14]

(In the formula, R ⁹ represents a hydrogen atom or an alkyl group having 10 or less carbon atoms and may have a linear, branched or cyclic structure.) General formula (7)

[0117]

[Chemical 15]

(In the formula, R ¹⁰ represents a hydrogen atom or an alkyl group having 10 or less carbon atoms and may have a linear, branched or cyclic structure. R ¹¹ contains a hetero atom. A group having 1 to 10 carbon atoms may have a linear, branched or cyclic structure.
s represents 0 or an integer of 1 to 10. )

The polymer or polymerizable compound having at least one functional group among the polymerizable functional groups represented by the general formula (3), the general formula (4) or the general formula (5) is present in the presence of a polymerization initiator. The polymer solid electrolyte and / or polymer gel electrolyte can be formed by polymerization by heating, irradiation with actinic rays such as ultraviolet rays and electron beams. Moreover, the polymer or the polymerizable compound may be used alone or in combination of two or more kinds.

Other than a polymer or a polymerizable compound having at least one functional group among the polymerizable functional groups represented by the general formula (3), the general formula (4) or the general formula (5), which can be used in the present invention. The polymerizable compound is not particularly limited.

Specifically, for example, methyl methacrylate,
(Meth) acrylic acid alkyl ester such as n-butyl acrylate, various urethane acrylates, acrylamide, methacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, vinylene carbonate, (meth) acryloyl carbonate, N- (Meth) acrylamide compounds such as vinylpyrrolidone, acryloylmorpholine, methacryloylmorpholine, N, N-dimethylaminopropyl (meth) acrylamide, styrene compounds such as styrene and α-methylstyrene, N
N such as vinylacetamide and N-vinylformamide
Examples thereof include vinylamide compounds and alkyl vinyl ethers such as ethyl vinyl ether.

3-3-3 Electrolyte Salt The type of the electrolyte used in the present invention is not particularly limited, and an electrolyte containing ions which are desired to be used as carriers by electric charge may be used. In the electrolyte, particularly in the non-aqueous electrolyte It is desirable that the dissociation constant of is large.

Specific examples of these electrolyte salts include Li
Alkali metal salts of trifluoromethanesulfonic acid such as CF ₃ SO ₃ , NaCF ₃ SO ₃ and KCF ₃ SO ₃ , LiP
Alkali metal salts of hexafluorophosphoric acid such as F ₆ , NaPF ₆ and KPF ₆ , LiN (CF ₃ SO ₂ ) ₂ and LiN (CF ₃ C
_{F 2 SO 2) 2, [} (C 2 H 5) 4 N] [N (CF 3 SO 2) 2], LiN
Alkali metal salts of perfluoroalkanesulfonimide such _{(CF 3 CF 2 SO 2)} 2, LiN (CF 3 CO) 2, Li
N (CF ₃ CF ₂ CO) ₂ , [(C ₂ H ₅ ) ₄ N] [N (CF ₃ C
O) ₂ ], LiN (CF ₃ CF ₂ CO ₂ ) ₂ and other alkali metal salts of perfluoroalkanecarboxylic acid imides, LiClO
₄ , alkali metal salt of perchloric acid such as NaClO ₄ , LiB
Tetrafluoroborate salts such as F ₄ and NaBF ₄ , LiSC
_{N, LiAsF 6, LiI, NaI} , NaAsF 6, KI
Examples thereof include, but are not limited to, alkali metal salts and the like.

Specific examples of the ammonium salt include quaternary ammonium salts of perchloric acid such as tetraethylammonium perchlorate, quaternary ammonium salts of tetrafluoroboric acid such as (C ₂ H ₅ ) ₄ NBF ₄ , and (C ₂ H ₅ ) Quaternary ammonium salts such as ₄ NPF ₆ , (CH ₃ ) ₄ P · BF ₄ , (C ₂ H ₅ ) ₄ P
Examples thereof include, but are not limited to, quaternary phosphonium salts such as BF ₄ .

Among these electrolytes, the ones that dissolve in an organic solvent are used.
LiPFF from the solubility and ionic conductivity ₆, LiBF_Four, Li
AsF₆, Perfluoroalkane sulfonic acid imide
Potassium metal salts and quaternary ammonium salts are preferred.

Particularly, LiPF ₆ , LiBF ₄ , and perfluoroalkanesulfonic acid imide salt are preferable because of their large dissociation constants in a non-aqueous solvent.

The composite ratio of the solvent and / or polymer component in the electrolyte of the present invention and the electrolyte salt is preferably 0.1% by mass to 50% by mass of the electrolyte, based on the mass of the solvent and / or the polymer. % To 30% by mass is more preferable. When the electrolyte used in the composite is present in a proportion of 50% by mass or more, migration of ions is significantly inhibited, and conversely, in a proportion of 0.1% by mass or less, the absolute amount of ions is insufficient and the ionic conductivity is reduced. .

3-4. Separator When the electrolyte of the present invention is used in combination with a separator, a battery having less cycle and better cycleability can be obtained. The material used for such a separator is not particularly limited, it has heat resistance, redox resistance, and there is no problem in strength even when formed into a thin film, as long as it is used for a normal non-aqueous battery. Good. For example, a polyolefin-based nonwoven fabric or a microporous film and / or a hydrophilically treated product thereof, a microporous film of a fluororesin such as Teflon, etc. may be mentioned.

The thickness of the separator to be used is preferably as thin as possible as long as it has strength, and the separator having a thickness of 5 μm to 50 μm is usually used. Further, the porosity is preferably as high as possible, but if it is too high, problems such as short circuit may occur, so that it is usually possible to use a porosity in the range of 35% to 90%.

4. Battery The entire positive electrode / electrolyte + separator / negative electrode laminate thus obtained is housed in a battery outer casing such as an aluminum laminate or a polyolefin resin, and sealed with an insulating resin such as a polyolefin resin or an epoxy resin. The battery of the present invention as shown in is obtained.

The structure of the battery of the present invention is not limited to the sheet type shown in FIG. 1, but may be any shape such as a chip type, a coin type, a square type and a cylindrical type. Also, various sizes can be manufactured. Although the thinness of the battery depends on the shape, it may be 1 mm or less, for example, about 0.5 mm in sheet type.

For the current collector 4, it is preferable to use a material having electron conductivity, electrochemical corrosion resistance, and a large specific surface area as much as possible. For example, various metals and their sintered bodies, electron conductive polymers, carbon sheets and the like can be mentioned.

An example of the battery manufacturing method according to the present invention will be described below.

The positive electrode 1 and the negative electrode 3 are put into the structure for battery construction including the current collector 4 so as not to come into contact with each other through the porous separator 2. Next, the electrolyte material of the present invention can be injected and impregnated to obtain a battery.

When the polymerizable composition-based electrolyte is injected into the electrolyte material, the polymerizable composition is cured and solidified and / or gelled by heating or irradiation with actinic rays after the injection and impregnation, thereby forming an electrode. A battery containing a polymer solid electrolyte and / or a polymer gel electrolyte that are evenly adhered can be obtained. Then, it is sealed with an insulating resin such as a polyolefin resin or an epoxy resin. In addition, the battery structure is S
Metals such as US, polypropylene, aluminum-laminated heat-sealing resin, polyimide, ethylene-vinyl alcohol copolymer, or ceramic materials such as conductive or insulating glass may be used, but are particularly limited to those made of these materials. However, the shape may be any shape such as a tubular shape, a box shape, and a sheet shape.

In a battery containing a polymer solid electrolyte and / or polymer gel electrolyte, the positive electrode and / or the negative electrode is impregnated with the electrolyte of the present invention, and the polymerizable composition-based electrolyte of the present invention is uniformly applied on either one of the electrodes. A method of forming a polymer solid electrolyte membrane and / or polymer gel electrolyte membrane having a uniform thickness on the electrode by polymerizing by the above-mentioned method after coating so as to have a uniform thickness may be adopted. Then, the other electrode is attached to the polymer solid electrolyte layer and / or the polymer gel electrolyte layer, placed in the structure for battery construction, and sealed with an insulating resin such as a polyolefin resin or an epoxy resin to obtain the desired You can also get a battery.

[0137]

EXAMPLES The present invention will be specifically described below by showing typical examples. Note that these are merely examples for description, and the present invention is not limited to these.

Example 1: PT-A / Ketjen Black
(Hereinafter, abbreviated as “KB”. Mass composition ratio 85:15) Electrode
Synthesis of material and molding of positive electrode using the same PT-A represented by the structural formula (1) was polymerized in the presence of KB to produce an electrode material in which PT-A was coated on KB. Structural formula (1)

[0139]

[Chemical 16]

The method for polymerizing PT-A is described in the literature (Chemis.
It was synthesized according to reaction formula (3) according to try Letters, p. 946, 2000). Reaction formula (3)

[0141]

[Chemical 17]

Bis-S-benzyl-p-phenylenethiourea (0.25 mmol, 1.02 g) and p synthesized from p-phenylenedithiourea and benzyl chloride.
-Phenylene diisothiocyanate (0.25 mmo
1, 0.48 g) was dissolved in 500 ml of THF,
Add 0.22g of Ketjen Black, 400 rp
The mixture was refluxed in nitrogen at a stirring rate of m for 100 hours. The black precipitate reaction liquid was filtered and washed with THF and ethanol to obtain 1.47 g of PT-A / KB electrode material powder. The CHNS elemental analysis and IR spectrum of the obtained powder almost supported the target structure. Elemental analysis C /
From the S element ratio, the PT-A: KB weight ratio in the electrode material powder was estimated to be 85:15.

The electrode material powder and polyvinylidene fluoride (hereinafter abbreviated as "PVDF") as an electrode binder were mixed in a weight ratio of 20: 1, and then mixed with N-methylpyrrolidone (hereinafter, "N-methylpyrrolidone").
Abbreviated as “MP”. ) Was added to form a paste, which was coated on an aluminum foil (25 μm) with a coater, volatilized with NMP, and pressure-molded to about 100 μm (including the aluminum foil thickness) with a roll press. This sheet was cut into 36 mm square, and the positive electrode for the battery (96.03 mg, mass composition ratio PT-A: KB: PV
DF = 85: 15: 5). 9m of part of the positive electrode
Punched to mφ and peeled off from aluminum foil, thickness 7
The bulk density was 0.95 g / cc at 8 μm. When this sample was measured with a 4-terminal conductivity meter, it was found to be 0.25S.
/ Cm (25 ° C).

Comparative Example 1: Synthesis of PT-A single powder and its preparation
Polymerization was performed in the same manner as in Example 1 except that the positive electrode molding KB using this was not added, and PT
-A single powder was synthesized. That is, after refluxing for 100 hours, the reaction solution was filtered and washed with THF and ethanol to obtain 0.98 g of PT-A as a yellow powder. C of the obtained powder
The HNS elemental analysis and IR spectrum almost supported the desired structure. This polymer, KB and PVDF were mixed at a mass composition ratio of 85: 15: 5, NMP was added and kneaded well to form a paste, which was coated on an aluminum foil (25 μm) with a coater. It was pressure-molded to 100 μm (including aluminum foil thickness). This sheet is 36mm
It was cut into a corner and used as a positive electrode for a battery (95.02 mg, mass composition ratio PT-A: KB: PVDF = 85: 15: 5). A part of the positive electrode was punched out to a diameter of 9 mm and peeled off from the aluminum foil. The thickness was 78 μm and the bulk density was 0.91 g /
It was cc. When this sample was measured with a 4-terminal conductivity meter, it was 0.11 S / cm (25 ° C.).

Example 2: PT-A / KB electrode material (mass
PT-A: KB (mass composition ratio PT-A: KB =) in the same manner as in Example 1 except that the composition of the composition ratio of 75:25) and the molding of the positive electrode using the same were changed. 7
5:25) Electrode material powder was synthesized, PVDF was used as an electrode binder, and the positive electrode (PT-A: KB: PVDF = 7).
5: 25: 5).

Comparative Example 2: Synthesis of PT-A single powder and its synthesis
Molding of positive electrode using the same PT-A: KB: PVDF (75: 2) using the PT-A single powder synthesized in Comparative Example 1 in the same manner as in Comparative Example 1.
5: 5) The mixture was prepared and molded as a positive electrode.

Example 3: PT-A / acetylene black
(Hereinafter, abbreviated as “AB”.) Electrode material (mass composition ratio 8
5:15) and molding of positive electrode using the same PT-A: AB (mass composition ratio PT-) in the same manner as in Example 1 except that AB was used instead of KB used in Example 1. A: AB = 85: 15) electrode material powder was synthesized, and PVDF was used as the electrode binder, and the positive electrode (PT
-A: AB: PVDF = 85: 15: 5).

Comparative Example 3: Positive electrode using PT-A single powder
Molding of PT PT was prepared in the same manner as in Comparative Example 1 except that AB was used instead of KB using the PT-A single powder synthesized in Comparative Example 1.
-A: AB: PVDF (85: 15: 5) mixture was prepared and molded as a positive electrode.

Example 4: Conductivity of various PT-A type positive electrodes,
Measurement of bulk density PT obtained in Examples 1 to 3 and Comparative Examples 1 to 3
Table 1 shows the electrical conductivity (25 ° C.) and bulk density of each of the -A type positive electrodes.

[0150]

[Table 1]

As shown in Table 1, the samples of Examples 1 to 3 in which PT-A and the carbon material were compounded at the time of polymerization were P
Comparative Examples 1 to 1 in which the T-A single powder and the carbon material were mixed later
Compared to Comparative Example 3, even with the same mass composition ratio, high conductivity and high bulk density were exhibited.

Example 5: PT-B / KB electrode material (mass
Synthesis of composition ratio 85:15) and molding of positive electrode using the same PT-B represented by the structural formula (2) was polymerized in the presence of KB to produce an electrode material in which PT-B was coated on KB.

Structural formula (2)

[0154]

[Chemical 18]

The method of polymerizing PT-B is described in the literature (JP 2000
No. 248054, gazette), it synthesize | combined like reaction formula (4).

Reaction formula (4)

[0157]

[Chemical 19]

That is, terephthalthioamide (18.4 m
mol (3.6 g) was suspended in a mixed solvent of 95% formic acid 15 cc / 70% perchloric acid aqueous solution 15 cc, and KB (0.7
g) was added and 30% hydrogen peroxide (18.4 mmol,
2.1 cc) was added dropwise, and the stirring speed was 400 rpm, 70
The reaction was performed for 5 hours. Then, the temperature was returned to room temperature, the obtained blackish brown precipitate solution was diluted with 50 cc of distilled water, filtered,
It was washed with water and THF. The filter residue was dried to obtain PT-B / KB electrode material powder (3.5 g) as a black solid. The CHNS elemental analysis and IR spectrum of the obtained powder almost supported the target structure. From the C / S element ratio of the elemental analysis, the PT-B / KB mass composition ratio in the electrode material powder was estimated to be 85:15.

After mixing this electrode material powder and PVDF at a mass composition ratio of 20/1, NMP was added to form a paste,
Coated on aluminum foil (25 μm) with a coater, volatilized with NMP, and then rolled to about 100 μm (including aluminum foil thickness).
Was pressure molded. This sheet was cut into a 36 mm square and used as a positive electrode (101.1 mg) for a battery. When a part of the positive electrode was punched out to 9 mmφ and peeled off from the aluminum foil,
The thickness was 78 μm and the bulk density was 1.00 g / cc. When this sample was measured with a 4-terminal conductivity meter, 1.
It was 05 S / cm (25 ° C.).

Comparative Example 4: Synthesis of PT-B single powder and its preparation
Polymerization was performed in the same manner as in Example 5 except that the positive electrode molding KB using this was not added, and 3.0 g of black PT-B alone powder was obtained. C of the obtained powder
The HNS elemental analysis and IR spectrum almost supported the desired structure. This polymer, KB and PVDF were mixed at a mass composition ratio of 85: 15: 5, NMP was added and kneaded well to form a paste, which was applied on an aluminum foil (25 μm) with a coater, and after NMP volatilization, it was rolled to about It was pressure-molded to 100 μm (including aluminum foil thickness). This sheet is 36mm
It was cut into a corner and used as a positive electrode for a battery (98.30 mg, mass composition ratio PT-B: KB: PVDF = 85: 15: 5). A part of the positive electrode was punched out to a diameter of 9 mm and peeled off from the aluminum foil. The thickness was 78 μm and the bulk density was 0.98 g /
It was cc. When this sample was measured with a 4-terminal conductivity meter, it was 0.78 S / cm (25 ° C.).

Example 6: PT-B / AB (mass composition ratio 8
5:15) A PT-B / AB electrode material (weight composition ratio 85:15) was synthesized in the same manner as in Example 4 except that the electrode material was synthesized and a positive electrode molding using the same was replaced with AB. In addition, PVDF was used as the electrode binder, and the positive electrode (PT
-A: AB: PVDF = 85: 15: 5).

Examples 7 and 8: PT-B / AB electrode material
Synthesis and Molding of Positive Electrode Using the Same PT-B / AB electrode material (weight composition ratio 90:10 or 95: 5) was synthesized in the same manner as in Example 6, and PV was further added.
DF is used as an electrode binder, and the positive electrode (PT-A: AB: PV
DF = 90: 10: 5 or 95: 5: 5).

Comparative Example 5: Synthesis of PT-B single powder and its synthesis
Molding of positive electrode using this PT-B was prepared in the same manner as in Comparative Example 1 except that AB was used in place of KB using the PT-B single powder synthesized in Comparative Example 4.
-A: AB: PVDF (85: 15: 5) mixture was prepared and molded as a positive electrode.

Example 9: Conductivity of various PT-B type positive electrodes,
Measurement of bulk density PT obtained in Examples 5 to 8 and Comparative Examples 4 and 5
Table 2 shows the electric conductivity (25 ° C.) and bulk density of each of the -B type positive electrodes.

[0165]

[Table 2]

As shown in Table 2, the samples of Example 5 to Example 8 in which PT-B and the carbon material were composited at the time of polymerization were P
Comparative Example 4 in which the T-B single powder and the carbon material are later mixed,
Compared to Comparative Example 5, even with the same mass composition ratio, high conductivity and high bulk density were exhibited.

Further, as compared with the PT-A type positive electrode in Table 1, PT
It was found that the -B type positive electrode has high conductivity, and the conductivity is high even if the amount of carbon material added is reduced.

Example 10: Production of Li Metal Negative Electrode 200 μm of this Li foil was pressure-bonded onto a 20 μm copper foil, and L
The i-metal negative electrode sheet was used. This sheet was cut into a 40 mm square to prepare a negative electrode for a battery.

Example 11: Production and evaluation of Li secondary battery Li negative electrode (40 m) in an argon atmosphere glove box.
m square) and the various PT positive electrodes formed in Examples 1 to 3 and 5 to 8 and Comparative Examples 1 to 5 with a 25 μm polyethylene microporous film separator (Asahi Kasei high pore) interposed, and the positive electrode and negative electrode contact each other. Stick together to avoid
This laminated body was put in a bag (exterior body) made of a PP / Al / PET three-layer laminate. Then 1 mol of LiBF ₄
Mixture of salt-containing ethyl methyl carbonate (EMC) and ethylene carbonate (EC) (7: 3 volume ratio) Electrolyte solution (1M LiBF ₄ / EC + EMC (3: 7)) was added and the electrolyte solution was applied to the positive electrode, negative electrode and separator. After impregnating and discharging the excess electrolytic solution under reduced pressure, the degree of airtightness of the laminate was increased and sealed to prepare a thin laminated battery as shown in FIG.

This battery was operated at 25 ° C. with an operating voltage of 2.0 to
When charging and discharging were repeated at 4.5 V and a current of 7 mA, the maximum discharging capacity and the discharging capacity after 50 times of charging and discharging became as shown in Table 3.

[0171]

[Table 3]

As shown in Table 3, the samples of Example 1 to Example 3 and Example 5 to Example 8 in which PT and the carbon material were compounded at the time of polymerization were compared with each other in which PT alone powder and the carbon material were later mixed. Compared to the example, even if the mass composition ratio is the same, the maximum discharge capacity is large, and the capacity decrease is small when charging and discharging are repeated.
Compared with the PT-A type positive electrode type, the PT-B type positive electrode had an initial high capacity, and the capacity decrease was large when charging and discharging were repeated.

Example 12: PT-B / vapor grown graphite fiber
(Hereinafter, abbreviated as "VGCF".) (Mass composition ratio 85: 1
5) A PT-B / VGCF electrode was prepared in the same manner as in Example 4, except that VGCF (average fiber diameter 0.1 μm, average aspect ratio 10) was used instead of the synthesis of the electrode material and molding KB of the positive electrode using the same. Material (weight composition ratio 85:15)
Was synthesized, and PVDF was further used as an electrode binder to form a positive electrode (PT-A: VGCF: PVDF = 85: 15: 2).

The conductivity (25 ° C.) of the obtained PT-A / VGCF positive electrode was 1.80 S / cm, and the bulk density was 1.00.
It was g / cc.

Example 13: Production and evaluation of Li secondary battery Using the PT-B / VGCF positive electrode prepared in Example 12, a thin laminated battery as shown in FIG. 1 was prepared in the same manner as in Example 11. did. When this battery was repeatedly charged and discharged at 25 ° C. with an operating voltage of 2.0 to 4.5 V and a current of 7 mA, the maximum discharge capacity was 32.8 mAh and the charge and discharge was 50.
The discharge capacity after rotation was 26.3 mAh.

Example 14: Preparation of thermopolymerizable composition Triethylene glycol diacrylate (hereinafter referred to as "TE
Abbreviated as “GA”. ) And (1.0 g) and 5.0 g of EMC,
2.0 g EC, 0.85 g LiBF ₄ and polymerization inhibitor 2,4-diphenyl-4-methyl-1-pentene 1.
8 mg, t-hexyl peroxypivalate (trade name perhexyl PV, NOF Corporation) as a thermal polymerization initiator
18 mg) was thoroughly mixed in an argon atmosphere to obtain a polymerizable composition A for solid polymer electrolyte.

Example 15: Preparation of Polymer Solid Electrolyte Membrane The polymerizable composition A for polymer solid electrolyte prepared in Example 14 was subjected to argon atmosphere in the presence of aluminum oxide C (secondary particles having an average particle size of about 0). .2 μm, Japan
By adding 0.20 g of Aerosil Co., Ltd., specific surface area of about 100 m2 / g, and stirring and mixing for 5 minutes,
A polymerizable composition B for a polymer solid electrolyte containing milky white inorganic particles was prepared.

The composition B was coated on a polypropylene (PP) film in a thickness of 30 μm under an argon atmosphere, further covered with a PP film, and the pair of PP films was further sandwiched between two glass plates having a thickness of 1.1 mm. . Next, after heating this glass plate set at 60 ° C. for 60 minutes, the glass plate and the PP film were peeled off, and a polymer solid electrolyte membrane was obtained as a thin white turbid color self-supporting membrane of about 30 μm.

[0179] 25 ° C. This film was measured for ionic conductivity at -10 ° C. by an impedance method, respectively, 3.5 × 10 ^{- 3,} it was 0.8 × 10 ^-3 S / cm.

Example 16: Production of solid state Li secondary battery,
Evaluation Li negative electrode (40 m
m square) and the PT-B / KB positive electrode molded in Example 5,
The polymer solid electrolyte membrane having a thickness of 30 μm produced in Example 15 was interposed, and the positive electrode and the negative electrode were attached so as not to come into contact with each other,
This laminated body was put in a bag (exterior body) made of a PP / Al / PET three-layer laminate. Then, the thermopolymerizable composition A for solid polymer electrolyte prepared in Example 14 was added to impregnate the whole composition into the positive electrode and the laminate, and the excess composition A was discharged under reduced pressure. After increasing the degree of tightness and sealing, the composition A is heated at 60 ° C. for 60 minutes.
By curing the above, the thin laminated battery shown in FIG. 1 in which the electrolyte was solidified was prepared.

This battery was operated at 25 ° C. and an operating voltage of 2.0 to
When the battery was repeatedly charged and discharged at 4.5 V and a current of 7 mA, the maximum discharge capacity was 35.3 mAh, which was lower than that of the liquid electrolyte, but the discharge capacity after 50 times of charge and discharge was improved to 32.5 mAh, and deterioration due to charge and discharge was observed. Has been improved.

[0182]

EFFECTS OF THE INVENTION The electrode material characterized in that the polymer of the compound containing sulfur is formed on the surface of the carbon material of the present invention is superior in the energy density and the like as compared with the conventional Li-based electrode material. Further, the electrode made of this electrode material can take out a sufficient current at room temperature. Further, as a method for producing the same, since it is uniformly compounded at the time of synthesizing a polymer of a compound containing sulfur, it has high conductivity and good moldability.

The electrode made of the electrode material has a high charge / discharge capacity due to Li absorption / desorption, and is stable against repeated charge / discharge. Therefore, the Li secondary battery using the electrode also has a high energy density and excellent charge / discharge cycle characteristics. Furthermore, since a solid and / or gel electrolyte can be used as the electrolyte of the secondary battery, it is more stable,
A battery having excellent reliability and safety can be obtained.

[0184]

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an example of a thin battery shown as an example of a Li secondary battery of the present invention.

[Explanation of symbols]

1 positive electrode 2 electrolyte 3 Negative electrode 4 Current collector 5 lead wires 6 Laminated exterior body

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5H029 AJ02 AJ03 AJ05 AJ12 AK15                       AL02 AL04 AL06 AL07 AL12                       AM00 AM02 AM03 AM04 AM05                       AM07 AM16 BJ04 CJ14 CJ22                       DJ08 DJ15 DJ16 EJ04 HJ01                       HJ05 HJ08 HJ14 HJ20                 5H050 AA02 AA07 AA08 AA15 BA17                       BA18 CA26 CB02 CB05 CB07                       CB08 CB12 DA10 EA08 EA09                       EA10 FA16 FA17 FA18 GA15                       GA22 HA01 HA05 HA08 HA14                       HA17

Claims (20)

[Claims] 1. An electrode material in which a polymer of a compound containing sulfur is formed on the surface of a carbon material. 2. The polymer of a compound containing sulfur is a polymer containing at least one dithiazoline ring and / or dithiazolium ring.
The electrode material according to. 3. The electrode material according to claim 1 or 2, wherein the polymer of the compound containing sulfur is a polymer represented by the following general formula (1). General formula (1) (In the formula, R ¹ represents a hydrogen atom, a halogen atom, a nitro group, or an organic group having 1 to 20 carbon atoms which may have a hetero atom, and plural R ¹ may be independently bonded to the benzene ring. N is an integer. It is.) 4. The electrode material according to claim 1 or 2, wherein the polymer of the compound containing sulfur is a polymer represented by the following general formula (2). General formula (2) (In the formula, R ² represents hydrogen, a halogen, a nitro group, or an organic group having 1 to 20 carbon atoms which may have a hetero atom, and a plurality of R ² may be independently bonded to the benzene ring. M is an integer. And X represents an anion.) 5. The carbon material is at least one selected from the group consisting of carbon blacks, activated carbons, carbon fibers, and graphites.
The electrode material according to claim 4. 6. The carbon material is a fibrous carbon material having an aspect ratio of 5 or more, wherein the carbon material is a fibrous carbon material.
The electrode material according to any one of 1. 7. The content of the carbon material is in the range of 1% by mass to 50% by mass, wherein the content is in the range of 1% by mass to 50% by mass.
The electrode material according to any one of 1. 8. The electrode material according to claim 1, which has a volume conductivity at 25 ° C. of 0.1 S / cm or more. 9. The method for producing an electrode material according to claim 1, wherein a polymer of a compound having sulfur is formed in the presence of a carbon material. 10. The method of reacting a compound having an isothiocyanate group with a (S-alkyl) thiourea group in the presence of a carbon material to form a polymer of a compound having sulfur on the surface of the carbon material. The method for producing the electrode material according to any one of claims 1 to 8, which is characterized. 11. A compound of thioamide group-containing compound is oxidized and polycondensed in the presence of a carbon material to form a polymer of a compound having sulfur on the surface of the carbon material. Item 9. A method for producing an electrode material according to any one of items 8. 12. A battery electrode, comprising the electrode material according to claim 1 as one of constituent elements. 13. The battery electrode according to claim 12, wherein a redox reaction is possible by absorbing and releasing Li ions. 14. The battery electrode according to claim 12, wherein the electrode density is 0.8 g / cm ³ or more. 15. A battery comprising the battery electrode according to claim 12 as one of constituent elements. 16. A battery comprising the battery electrode according to any one of claims 12 to 14 as one of the constituent elements, capable of performing a charge / discharge reaction by absorbing and releasing Li ions, and using a non-aqueous electrolyte. Non-aqueous secondary battery to be. 17. The non-aqueous secondary battery according to claim 16, wherein the non-aqueous electrolyte is at least one selected from the group consisting of a solid electrolyte and a gel electrolyte. 18. The non-electrolyte according to claim 17, wherein the solid electrolyte or gel electrolyte is an electrolyte obtained by reacting a mixture of a polymerizable compound having a double bond and a Li ion conductive substance. Aqueous secondary battery. 19. The non-aqueous secondary battery according to claim 17, wherein the solid electrolyte or gel electrolyte contains at least one kind of non-electroconductive powder. 20. The non-electroconductive powder is 0.001 μm
The non-aqueous secondary battery according to claim 19, which is an inorganic powder having a particle diameter in the range of 10 µm.