JP2009059774A - Method of manufacturing electrochemical capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an electrochemical capacitor which can be made high in voltage to a predetermined voltage. <P>SOLUTION: The manufacturing method of the electrochemical capacitor includes: forming an electron conduction layer by coating a release sheet with paste for the electron conduction layer; forming an electrode-electron conduction layer assembly by coating the electron conduction layer with paste for an electrode; sandwiching a polymer electrolyte film between a pair of obtained electrode-electron conduction layer assemblies and peeling release sheets to form a structure consisting of the electron conduction layer, the electrode, the electrolyte film, the electrode, and the electron conduction layer; and forming a layered body by alternately stacking and integrating a plurality of structures obtained by cutting out structures from the structures each consisting of the electron conduction layer, the electrode, the electrolyte, the electrode, and the electron conduction layer to a predetermined size and a plurality of collectors so that the outermost parts become the collectors. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an electrochemical capacitor. More specifically, the present invention relates to a method for manufacturing an electrochemical capacitor that has low resistance, high output density, high reliability, and high voltage to a predetermined voltage without causing corrosion.

  Electrochemical elements such as electric double layer capacitors are easy to reduce in size and weight, so they are used in small equipment as backup power sources to replace batteries, and as auxiliary power sources for large batteries for fuel cell vehicles and hybrid vehicles. Studies are also being actively conducted.

  Therefore, in recent years, large-capacity electrochemical element technology has attracted attention as an energy storage device. The large-capacity electrochemical device uses an electric double layer capacitor that uses the electric double layer generated at the electrode / electrolyte interface mainly for power storage, and a metal oxide or conductive polymer as the electrode. There are redox capacitors that utilize reaction (pseudo electric double layer capacitance), and these are often collectively referred to as electrochemical capacitors.

  Among these, a redox capacitor using a metal oxide has a high energy density. For example, it is known that a redox capacitor using ruthenium oxide hydrate as a metal oxide and using an aqueous sulfuric acid solution as an electrolyte has an energy density several times that of an electric double layer capacitor using ordinary activated carbon.

  An electrochemical capacitor using a metal oxide as an electrode can provide a large capacity, but when a high-concentration sulfuric acid aqueous solution is used as an electrolyte, a countermeasure against corrosion is necessary. For example, in the case of a conventional electric double layer capacitor using activated carbon as an electrode and a high-concentration sulfuric acid aqueous solution as an electrolyte, a method using a composite material of rubber and conductive carbon as a current collector is widely used. Although this type of composite material is effective as a countermeasure against corrosion, it has a problem that it is difficult to obtain a large input / output density because it has higher resistance than metal and generates resistance loss during charging and discharging.

  Therefore, as the electrolyte, a material having high proton conductivity, good electrical connection with the electrode, and no risk of corrosion, which can replace the concentrated sulfuric acid aqueous solution in which the material used is restricted, is required.

  Moreover, in order to form a metal oxide as an electrode, a binder is required. Commonly used binders include Teflon (registered trademark), polyvinylidene fluoride, and rubber-based emulsions. However, since these materials do not have proton conductivity, they are charged and discharged as described above. It is a major factor that causes resistance loss at the time, and a material having high proton conductivity, strong electrode binding, and no risk of corrosion is required.

  Furthermore, from the viewpoint of practical use, when ruthenium oxide hydrate is used as a metal oxide, ruthenium is expensive, and the voltage in an electrochemical capacitor single cell is 1 V or less. There is a problem in that it needs to be connected and becomes structurally complicated. For the above reasons, no practical application example of a redox capacitor using ruthenium oxide hydrate has been reported yet.

In addition, it is known that electric double layer capacitors using ordinary activated carbon have much superior durability and reliability compared to secondary batteries such as nickel-hydrogen secondary batteries and lithium ion secondary batteries. Yes. The durability life and reliability are generally evaluated by a float charge test at 70 ° C.

On the other hand, the durability and reliability of redox capacitors using metal oxides are not well known, and as with secondary batteries, they have a charge / discharge process that involves mass transfer due to oxidation and reduction. Sex is a concern.
JP 2006-49866 A

  An object of the present invention is to solve the above-mentioned problems with respect to corrosion resistance, input / output characteristics and complexity of the manufacturing process, have excellent power storage performance and durable life, high reliability, An object of the present invention is to provide a method for manufacturing an electrochemical capacitor capable of increasing the voltage.

  In order to solve the above problems, the present inventors have intensively studied a multilayer electrochemical capacitor. As a result, a non-corrosive aromatic polymer electrolyte membrane was used as the electrolyte layer, and an electron conductive layer was interposed between the electrode layer and the current collector, and the electron conductive layer-electrode-electrolyte membrane- The present inventors have found a method for producing an electrochemical capacitor which is excellent in corrosion resistance and input / output characteristics by forming a structure composed of an electrode-electron conductive layer and laminating it, and capable of increasing the voltage to a predetermined voltage.

  That is, the method for manufacturing an electrochemical capacitor according to the present invention includes a step of applying an electron conductive layer paste on a release sheet to form an electron conductive layer, and applying an electrode paste on the electron conductive layer. After the step of forming the electrode-electron conducting layer assembly and the aromatic polymer electrolyte membrane sandwiched and joined with the obtained pair of electrode-electron conducting layer assemblies, the release sheet is peeled off, And a step of forming a structure composed of an electron conductive layer-electrode-electrolyte membrane-electrode-electron conductive layer.

  It is preferable that the aromatic polymer electrolyte membrane is a sulfonic acid group-containing polyarylene including a structural unit represented by the following formula (A) and a structural unit represented by the following formula (B).

In the formula (A), Y represents —CO—, —SO ₂ —, —SO—, —CONH—, —COO—, — (
CF ₂ ) _i — (wherein i represents an integer of 1 to 10) and at least one structure selected from the group consisting of —C (CF ₃ ) ₂ —, Z is a direct bond, or — (CH ₂ ) _J — (j represents an integer of 1 to 10), —C (CH ₃ ) ₂ —, —O— and —S— represent at least one structure, and Ar represents —SO ₃ H, —O (CH ₂ ) _p SO ₃ H or —O (CF ₂
) _P represents an aromatic group having a substituent represented by SO ₃ H (p represents an integer of 1 to 12), m represents an integer of 0 to 10, and n represents an integer of 0 to 10. , K represents an integer of 1 to 4.

In the formula (B), A and D are each independently a direct bond, or —CO—, —SO ₂ —,
—SO—, —CONH—, —COO—, — (CF ₂ ) _i — (i represents an integer of 1 to 10), — (CH ₂ ) _j — (j represents an integer of 1 to 10). ), —CR ′ ₂ — (R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group), a cyclohexylidene group, a fluorenylidene group, —O— and —S—. 1 represents at least one structure selected from the group, B is independently an oxygen atom or a sulfur atom, R ^{1 to} R ¹⁶ may be the same or different from each other, and may be a hydrogen atom, a fluorine atom, an alkyl group, one Represents at least one atom or group selected from the group consisting of halogenated alkyl groups, allyl groups, aryl groups, nitro groups, and nitrile groups, all or part of which is halogenated, and s represents an integer of 0 to 4, t represents an integer of 0 to 4, r is Or an integer of 1 or more.

The electrode paste preferably contains ruthenium dioxide hydrate.
The application surface of the release sheet is preferably a fluorine material exhibiting releasability.
A method for producing an electrochemical capacitor according to the present invention includes a plurality of structures cut out to a predetermined size from a structure composed of the electron conductive layer-electrode-electrolyte membrane-electrode-electron conductive layer, and a plurality of current collectors. Preferably, the method further includes a step of forming a laminated body in which the outermost layers are alternately laminated and integrated so that the outermost portion is a current collector.

  The method for producing an electrochemical capacitor according to the present invention preferably further includes a step of immersing the laminate in hot water to perform a water treatment.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the electrochemical capacitor which is easy to manufacture, shows the favorable electrical storage performance excellent in corrosion resistance and output characteristics, has a high durability life, and can increase the voltage to a predetermined voltage. Can be provided.

Hereinafter, the method for producing an electrochemical capacitor according to the present invention will be described in detail.
The method for producing an electrochemical capacitor of the present invention comprises (A) a step of applying an electron conductive layer paste on a release sheet to form an electron conductive layer, and (B) an electrode paste on the electron conductive layer. A step of forming an electrode-electron conductive layer assembly by coating, and (C) sandwiching and joining the polymer electrolyte membrane between the obtained pair of electrode-electron conductive layer assemblies, and then releasing the release sheet And a step of forming a structure composed of an electron conductive layer-electrode-electrolyte membrane-electrode-electron conductive layer.

  The electrochemical capacitor manufacturing method according to the present invention includes a plurality of structures cut out to a predetermined size from a structure comprising (D) the electron conductive layer-electrode-electrolyte film-electrode-electron conductive layer, if necessary. Forming a laminated body in which the body and the plurality of current collectors are alternately laminated and integrated so that the outermost portion is the current collector.

  The method for producing an electrochemical capacitor according to the present invention further includes (E) a step of cutting off the end of the laminate, and (F) immersing the laminate in hot water as necessary. And / or (G) a step of ultrasonically cleaning the laminate by immersing the laminate in water.

[Step (A)]
In this step, the electron conductive layer is formed by applying an electron conductive layer paste on the release sheet. Here, it is preferable to dry the electron conductive layer after applying the electron conductive layer paste on the release sheet to form the electron conductive layer.

  Thus, by providing the electron conductive layer between the electrode layer and the current collector, which will be described later, the adhesion between the electrode layer and the current collector is improved without impairing the conductivity, and the electrochemical capacitor is deteriorated. Can be suppressed.

  In order to develop good electrochemical capacitor characteristics, it is preferable to form a thin electron conductive layer. From such a viewpoint, the thickness of the electron conductive layer is preferably 1 to 30 μm, more preferably 3 to 20 μm, and still more preferably 5 to 10 μm.

<Release sheet>
The release sheet is preferably a sheet having high releasability, and examples thereof include a fluororesin sheet and a fluorine material on which a coating surface such as polyethylene terephthalate coated with a fluororesin exhibits releasability. In these, in order to acquire reliable mold release property, it is preferable to use a fluororesin sheet.

  Examples of the fluororesin sheet include a polytetrafluoroethylene sheet, a tetrafluoroethylene copolymer sheet, and a polyvinylidene fluoride sheet. In these, it is preferable to use a polytetrafluoroethylene sheet for the toughness as a sheet | seat and the availability of a thin film product. Moreover, as the fluororesin sheet, commercially available products such as a Teflon (registered trademark) sheet (Naflon tape, manufactured by Nichias Co., Ltd.) can be suitably used.

The thickness of the release sheet is preferably 10 to 500 μm, more preferably 20 to 200 μm, and still more preferably 50 to 100 μm.
<Electroconductive layer paste>
The above-mentioned paste for an electron conductive layer preferably contains a thermoplastic elastomer and an electron conductive powder from the viewpoint of suppressing the adhesion between the electrode layer and the current collector and the deterioration of the electrochemical capacitor. The electron conductive layer paste can be prepared, for example, by dispersing or dissolving a thermoplastic elastomer and electron conductive powder in a low boiling point solvent.

  Moreover, as the above-mentioned paste for the electron conductive layer, a conductive adhesive can be used. For example, a commercially available product that exhibits rubber properties after drying, such as Bunny Height UCC (manufactured by Nippon Graphite), can also be used as it is.

Examples of the thermoplastic elastomer include styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-butylene-styrene block copolymer (SEBS), Functional group-added SEBS (f-SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), random type hydrogenated styrene-butadiene copolymer (HSBR), syndiotactic 1,2 polybutadiene ( RB), polyolefin-based thermoplastic elastomer (TPO), polyvinyl chloride-based thermoplastic elastomer (TPVC), polyurethane-based thermoplastic elastomer (TPU), polyester-based thermoplastic elastomer (TPEE), polyamide-based thermoplastic elastomer Stoma (TPA) is exemplified. In order for the thermoplastic elastomer to have strength and flexibility to avoid breakage during peeling or subsequent handling, the glass transition point of the resin phase is preferably 80 ° C. or higher, more preferably 80 to 150 ° C.
More preferably, it is 80-100 degreeC.

  Further, the thermoplastic elastomer which is soluble in a low boiling point solvent such as toluene is suitable for mixing with the electron conductive powder to form a thin layer. From such a viewpoint, a thermoplastic elastomer containing styrene is preferable. Furthermore, among thermoplastic elastomers containing styrene, it is more preferable to use SEBS, f-SEBS, SEPS, and HSBR that do not contain highly heat-stable unsaturated bonds, and SEBS is particularly preferable.

  Examples of the electron conductive powder include a carbon material such as carbon black and graphite, a noble metal powder such as gold and silver, or a magnetic powder such as nickel and cobalt plated with a noble metal.

  Furthermore, in order to form a thin electron conductive layer, the electron conductive powder includes carbon black that can ensure high electron conductivity even when the particle diameter is small, specifically, ketjen black EC, acetylene. Black, Vulcan XC72 and the like are preferable, but they may be mixed with other electron conductive powders.

Examples of the low boiling point solvent include toluene and xylene.
The mixing ratio of the electron conductive powder to the thermoplastic elastomer is preferably 20 to 200 parts by weight, more preferably 20 to 150 parts by weight, and further preferably 30 to 100 parts by weight with respect to 100 parts by weight of the thermoplastic elastomer. If it is less than 20 parts by weight, it tends to be difficult to ensure sufficient electron conductivity, and if it exceeds 200 parts by weight, it tends to be difficult to form a thin layer.

<Coating / Drying>
As a method for applying the electron conductive layer paste on the release sheet in this step, various known methods can be used without particular limitation. For example, a blade coater, a bar coater, a roll coater or the like can be used, but it is preferable to use a blade coater in order to easily ensure the uniformity of the film thickness.

  In the present step, it is preferable to dry the electron conductive layer. The electron conductive layer can be dried by heating for a predetermined time. Specifically, the drying is preferably performed under the conditions of a drying temperature of 40 to 150 ° C. and a drying time of 5 to 120 minutes, and the drying temperature of 60 to 120 ° C. and a drying time of 10 to 90 minutes. Is more preferable, and it is particularly preferable that the drying is performed under the conditions of a drying temperature of 80 to 100 ° C. and a drying time of 30 to 60 minutes.

[Step (B)]
In this step, an electrode-electron conductive layer assembly is formed by applying an electrode paste on the electron conductive layer. Here, after forming the electrode-electron conductive layer assembly, the assembly is preferably dried. The electrode layer thus formed is connected to a current collector described later via the electron conductive layer.

  In order to develop good electrochemical capacitor characteristics, it is preferable to form an electrode layer according to the requirements of the thickness and capacity of the electrochemical capacitor to be manufactured. When ruthenium oxide is used as the electrode material, the electrode layer is preferably a thin layer in order to reduce the amount of expensive ruthenium oxide used. From such a viewpoint, the thickness of the electrode layer is preferably 200 to 0.1 μm, more preferably 80 to 0.5 μm, and still more preferably 60 to 1 μm.

<Paste for electrodes>
The electrode paste includes a metal oxide. Further, in order to form a metal oxide as an electrode and suppress resistance loss during charge and discharge, it is preferable to include a polymer binder having proton conductivity. The electrode paste can be prepared, for example, by dispersing or dissolving the polymer binder and metal oxide in a volatile solvent.

As the metal oxide, any noble metal oxide or non-noble metal oxide can be used as long as it is a metal oxide used in a redox capacitor.
Examples of the noble metal oxide include RuO ₂ , IrO ₂ , a composite of RuO ₂ and IrO ₂ , R
a composite of uO ₂ and TiO _2, a composite of RuO ₂ and ZrO _2, a composite of RuO ₂ and Nb ₂ O ₅ , R
Examples include a composite of uO ₂ and SnO ₂ , a composite oxide of ruthenium and vanadium, a composite oxide of ruthenium and molybdenum, and a composite oxide of ruthenium and calcium.

Examples of the non-noble metal oxide include NiO, WO ₃ , Co ₃ O ₄ , MoO ₃ , TiO ₂ , and Fe ₃ O ₄ .
The metal oxide may be a hydrate. _{Specifically, RuO 2 · nH 2 O,} (Ru + Ir) O X · nH 2 O, Ru (1-y) Cr y O 2 · nH 2 O, MnO 2 · nH 2 O, V 2 O 5 · nH ₂ O, NiO.nH ₂ O and the like can be mentioned.

Among the above metal oxides, a non-crystalline hydrated metal oxide system is preferable because a high capacity can be obtained. In particular, non-crystalline RuO ₂ .nH ₂ O and (Ru + Ir) O _x .nH ₂ O are used. preferable.
The metal oxide is usually in the form of particles, and the particle size is preferably 0.01 to 5 μm, more preferably 0.05 to 5 μm, and still more preferably 0.1 to 5 μm. In order to enhance the electronic conductivity of the metal oxide, a conductivity imparting agent such as carbon black or graphite may be added simultaneously.

  Examples of the polymer binder having proton conductivity include a structural unit having a sulfonic acid group represented by the following formula (A) (hereinafter also referred to as “structural unit (A)” or “sulfonic acid unit”). And a structural unit having no sulfonic acid group represented by the following formula (B) (hereinafter also referred to as “structural unit (B)” or “hydrophobic unit”). A sulfonic acid group-containing polyarylene is preferred.

In the above formula (A), Y represents —CO—, —SO ₂ —, —SO—, —CONH—, —COO—,
_{- (CF 2) i - (} i is an integer from 1 to 10.) And -C (CF _{3) 2} - exhibits at least one structure selected from the group consisting of. Of these, —CO— and —SO ₂ — are preferable.

Z is a direct bond, or — (CH ₂ ) _j — (j represents an integer of 1 to 10), —C (CH ₃
) Shows at least one structure selected from the group consisting of _2- , -O- and -S-. Among these, a direct bond and —O— are preferable.

Ar is an aromatic having a substituent represented by —SO ₃ H, —O (CH ₂ ) _p SO ₃ H or —O (CF ₂ ) _p SO ₃ H (p represents an integer of 1 to 12). Indicates a group. Examples of the aromatic group include a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group, and a phenyl group and a naphthyl group are preferable. Ar represents —SO ₃ H, —O (CH ₂ ) _p SO ₃ H or —O (
It is necessary to have at least one substituent represented by CF ₂ ) _p SO ₃ H, and in the case of a naphthyl group, it is preferable to have two or more.

m is an integer of 0 to 10, preferably 0 to 2, n is an integer of 0 to 10, preferably 0 to 2, and k is an integer of 1 to 4.
As a preferred structure of the structural unit (A), in the above formula (A),
(1) a structure in which m = 0, n = 0, Y is —CO—, and Ar is a phenyl group having —SO ₃ H as a substituent;
(2) a structure in which m = 1, n = 0, Y is —CO—, Z is —O—, and Ar is a phenyl group having —SO ₃ H as a substituent;
(3) A structure in which m = 1, n = 1, k = 1, Y is —CO—, Z is —O—, and Ar is a phenyl group having —SO ₃ H as a substituent;
(4) m = 1, n = 0, Y is —CO—, and Ar is two substituents —SO _3.
A structure which is a naphthyl group having H,
(5) m = 1, n = 0, Y is —CO—, Z is —O—, and Ar is a phenyl group having —O (CH ₂ ) ₄ SO ₃ H as a substituent. Examples include structures.

In the above formula (B), A and D are each independently a direct bond, or —CO—, —SO _2.
-, - SO -, - CONH -, - COO -, - (CF 2) i -, (i is an integer from 1 to 10.) - a (j is an integer of from 1 to 10 - (CH _{2) j} -CR ' _2- (R' represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group), a cyclohexylidene group, a fluorenylidene group, -O- and -S- At least one structure selected from the group consisting of Among these, a direct bond, —CO—, —SO ₂ —, —CR ′ ₂ —, a cyclohexylidene group, a fluorenylidene group, and —O— are preferable. R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group. For example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, A propyl group, an octyl group, a decyl group, an octadecyl group, a phenyl group, a trifluoromethyl group, etc. are mentioned.

B is independently an oxygen atom or a sulfur atom, preferably an oxygen atom.
R ^{1 to} R ¹⁶ may be the same as or different from each other, and are a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group partially or wholly halogenated, an allyl group, an aryl group, a nitro group, and a nitrile group. At least one atom or group selected from the group consisting of

Examples of the alkyl group in R ^{1 to} R ¹⁶ include a methyl group, an ethyl group, a propyl group, a butyl group, an amyl group, a hexyl group, a cyclohexyl group, and an octyl group. Examples of the halogenated alkyl group include a trifluoromethyl group, a pentafluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, and a perfluorohexyl group. Examples of the allyl group include a propenyl group. Examples of the aryl group include a phenyl group and a pentafluorophenyl group.

s represents an integer of 0 to 4, and t represents an integer of 0 to 4. r shows 0 or an integer greater than or equal to 1, and an upper limit is 100 normally, Preferably it is 1-80.
As a preferred structure of the structural unit (B), in the above formula (B),
(1) s = 1, t = 1, A is —CR ′ ₂ —, a cyclohexylidene group or a fluorenylidene group, B is an oxygen atom, and D is —CO— or —SO ₂ —. , R ^{1 to} R ¹⁶ are hydrogen atoms or fluorine atoms,
(2) a structure in which s = 1, t = 0, B is an oxygen atom, D is —CO— or —SO ₂ —, and R ^{1 to} R ¹⁶ are hydrogen atoms or fluorine atoms,
(3) s = 0, t = 1, A is —CR ′ ₂ —, a cyclohexylidene group or a fluorenylidene group, B is an oxygen atom, and R ^{1 to} R ¹⁶ are a hydrogen atom, a fluorine atom, or a nitrile group. The structure etc. which are are mentioned.

In the above formula (C), A, B, D, Y, Z, Ar, k, m, n, r, s, t and R ^{1 to} R ¹⁶ are respectively in the above formulas (A) and (B). As defined. x and y are x +
The molar ratio when y = 100 mol% is shown.

  The sulfonic acid group-containing polyarylene contains the structural unit (A) in a proportion of 0.5 to 100 mol%, preferably 10 to 99.999 mol%, and contains 99.5 to 0 mol of the structural unit (B). %, Preferably 90 to 0.001 mol%.

Examples of the method for producing the sulfonic acid group-containing polyarylene include the following methods A, B and C.
(Method A) For example, in the method described in JP-A No. 2004-137444, a monomer having a sulfonate group that can be the structural unit (A) and a monomer or oligomer that can be the structural unit (B) are combined. A method of polymerizing to produce a polyarylene having a sulfonic acid ester group, deesterifying the sulfonic acid ester group, and converting the sulfonic acid ester group into a sulfonic acid group.

  (Method B) For example, in the method described in JP-A-2001-342241, a monomer having a skeleton represented by the above formula (A) but having neither a sulfonic acid group nor a sulfonic acid ester group; A method in which a monomer or an oligomer that can be the structural unit (B) is copolymerized, and the resulting copolymer is sulfonated using a sulfonating agent.

(Method C) When Ar in the above formula (A) is an aromatic group having a substituent represented by —O (CH ₂ ) _p SO ₃ H or —O (CF ₂ ) _p SO ₃ H Is, for example, copolymerized a precursor monomer that can be the structural unit (A) and a monomer or oligomer that can be the structural unit (B) by the method described in JP-A-2005-60625, A method of introducing an alkyl sulfonic acid or a fluorine-substituted alkyl sulfonic acid.

  Examples of the monomer having a sulfonate group that can be the structural unit (A) that can be used in the method A include, for example, JP-A Nos. 2004-137444, 2004-345997, and 2004-346163. Examples thereof include sulfonic acid esters described in Japanese Patent Publication No. Gazette.

  Examples of the monomer that can be used in the above-mentioned method B and has neither a sulfonic acid group or a sulfonic acid ester group that can be the structural unit (B) include, for example, JP-A Nos. 2001-342241 and 2002-293889. Mention may be made of the dihalides described in the publication.

  Examples of the precursor monomer that can be the structural unit (A) that can be used in the method C include dihalides described in JP-A-2005-36125.

  Specific examples of the sulfonic acid ester used in the method A include the following compounds.

  Moreover, the following compounds are mentioned as a specific example of the compound which does not have any of the sulfonic acid group and sulfonic acid ester group which are used by the said B method.

Moreover, as a monomer or oligomer that can be the structural unit (B) used in any method,
When r = 0, for example, 4,4′-dichlorobenzophenone, 4,4′-dichlorobenzanilide, 2,2-bis (4-chlorophenyl) difluoromethane, 2,2-bis (4-chlorophenyl) -1 , 1,1,3,3,3-hexafluoropropane, 4-chlorobenzoic acid-4-chlorophenyl ester, bis (4-chlorophenyl) sulfoxide, bis (4-chlorophenyl) sulfone, 2,6-dichlorobenzonitrile, etc. Is mentioned. Among these compounds, compounds in which a chlorine atom is replaced with a bromine atom or an iodine atom can also be used.

In the case of r = 1, for example, compounds described in JP-A-2003-113136 can be exemplified.
In the case of r ≧ 2, for example, JP 2004-137444 A, JP 2004-244517 A, JP 2004-346164 A, JP 2005-112985 A, JP 2006-28414 A, JP The compounds described in 2006-28415 can be mentioned.

  Examples of the monomer or oligomer that can be the structural unit (B) include compounds represented by the following formulas.

In order to obtain a polyarylene having a sulfonic acid group, first, a monomer that can be the structural unit (A) and a monomer or oligomer that can be the structural unit (B) are copolymerized in the presence of a catalyst, It is necessary to obtain arylene. The catalyst used in this case is a catalyst system containing a transition metal compound, and as such a catalyst system, (i) a compound that becomes a transition metal salt and a ligand (hereinafter referred to as “ligand component”), Alternatively, a transition metal complex coordinated with a ligand (including a copper salt) and (ii) a reducing agent may be essential components, and a “salt” may be added to increase the polymerization rate. For example, the conditions described in JP-A-2001-342241 can be adopted as specific examples of these catalyst components, the use ratio of each component, the reaction solvent, concentration, temperature, time and other polymerization conditions.

  The sulfonic acid group-containing polyarylene can be obtained by converting the precursor polyarylene obtained as described above into a polyarylene having a sulfonic acid group. As this method, there are the following three methods.

(Method a) A method of deesterifying the precursor polyarylene having a sulfonate group obtained by Method A by the method described in JP-A-2004-137444.
(Method b) A method of sulfonating the precursor polyarylene obtained in Method B by the method described in JP-A-2001-342241.

(Method c) A method of introducing an alkylsulfonic acid group into the precursor polyarylene obtained by the method C by the method described in JP-A-2005-60625.
The sulfonic acid group-containing polyarylene represented by the above formula (C) produced by the method as described above usually has a sulfonic acid group of 0.3 to 5 meq / g, preferably 0.5 to 3 meq / g. g, and more preferably 0.8 to 2.8 meq / g. When the amount of sulfonic acid group (ion exchange capacity) is lower than the above range, proton conductivity tends to be low and output characteristics tend to be lowered. On the other hand, if the amount of the sulfonic acid group exceeds the above range, the water resistance may be significantly lowered.

  The amount of the sulfonic acid group can be adjusted, for example, by changing the type, use ratio, and combination of the precursor monomer that can be the structural unit (A) and the monomer or oligomer that can be the structural unit (B). it can.

  The molecular weight of the sulfonic acid group-containing polyarylene obtained as described above is 10,000 to 1,000,000, preferably 10,000 to 800,000, more preferably 2 in terms of polystyrene-equivalent weight average molecular weight by gel permeation chromatography (GPC). 10,000 to 200,000.

  By using the sulfonic acid group-containing polyarylene as the polymer binder having proton conductivity, the exchange reaction of hydrogen ions at the interface between the electrode and the electrolyte proceeds smoothly, and good power storage characteristics are obtained.

  In addition, the polymer binder can ensure good binding between the electrode particles even when the amount added to the electrode material is small, and can provide good proton conductivity and electron conductivity. Charge / discharge performance with good energy density can be obtained.

Furthermore, since the use of the polymer binder can ensure good adhesion with the electron conductive layer, resistance loss at the electron conductive layer-electrode interface can be minimized.
The amount of the polymer binder contained in the electrode is preferably 2.5 to 50 parts by weight, more preferably 5 to 25 parts by weight with respect to 100 parts by weight of the metal oxide. If it is less than the lower limit of the above range, the adhesiveness with the electron conductive layer may be lowered, and if it exceeds the upper limit, the electron conductivity between the electrode particles is lowered, so that the charge / discharge characteristics may be lowered.

Examples of the volatile solvent include N-methyl-2-pyrrolidone, N, N-dimethylformamide, γ-butyrolactone, N, N-dimethylacetamide, dimethylsulfoxide, dimethylurea, and dimethylimidazolidinone (DMI). Examples include aprotic polar solvents, ether solvents such as dimethoxyethane, diethylene glycol monomethyl ether, and dioxane. N-methyl-2-pyrrolidone is particularly preferred from the viewpoint of solubility and solution viscosity. The said solvent may be used individually by 1 type, or may be used in combination of 2 or more type.

  Further, as a solvent for dissolving the sulfonic acid group-containing polyarylene, a mixture of the above aprotic polar solvent and alcohol may be used. Specific examples of alcohol include methanol, ethanol, propyl alcohol, iso-propyl alcohol, sec-butyl alcohol, tert-butyl alcohol and the like, and methanol is particularly preferable because it has an effect of lowering the solution viscosity in a wide composition range. . Alcohol may be used individually by 1 type, or may be used in combination of 2 or more type.

  Furthermore, as a solvent for dissolving the sulfonic acid group-containing polyarylene, a mixture of the ether solvent and water may be used. In particular, a mixture of dimethoxyethane and water is preferable when the electrode material is a highly hydrophilic material.

In addition, it is necessary to select a solvent so that the electrode paste does not dissolve the electron conductive layer, which is a base layer, at the time of application.
<Coating / Drying>
As a method of applying the electrode paste on the electron conductive layer in this step, various known methods can be used without particular limitation. For example, a blade coater, a bar coater, a roll coater or the like can be used, but it is preferable to use a blade coater in order to easily ensure the uniformity of the film thickness.

  In this step, the electrode-electron conductive layer assembly is preferably dried. The electrode-electron conductive layer assembly can be dried by heating for a predetermined time. Specifically, the drying is preferably performed under the conditions of a drying temperature of 40 to 150 ° C. and a drying time of 5 to 120 minutes, and the drying temperature of 60 to 120 ° C. and a drying time of 10 to 90 minutes. Is more preferable, and it is particularly preferable that the drying is performed under the conditions of a drying temperature of 80 to 100 ° C. and a drying time of 30 to 60 minutes.

[Step (C)]
In this step, the aromatic polymer electrolyte membrane is formed so that the bonding surface is the electron conductive layer and the aromatic polymer electrolyte membrane in the pair of electrode-electron conductive layer assemblies formed as described above. After sandwiching and joining, the release sheet is peeled off to form a structure composed of an electron conductive layer-electrode-electrolyte membrane-electrode-electron conductive layer. Here, the electrode-electron conductive layer assembly and the aromatic polymer electrolyte membrane may be cut into an arbitrary size and shape in advance in consideration of the subsequent steps.

<Aromatic polymer electrolyte membrane>
The aromatic polymer electrolyte membrane preferably contains a sulfonic acid group-containing polyarylene that can be suitably used as the polymer binder. The aromatic polymer electrolyte membrane is obtained, for example, by dissolving the sulfonic acid group-containing polymer in a solvent, adding an additive as necessary, and then casting it on a substrate to form a film ( It can be adjusted by a casting method).

  The thickness of the aromatic polymer electrolyte membrane thus adjusted is appropriately selected depending on the size, output, etc., but is preferably 15 to 150 μm, more preferably 20 to 100 μm, still more preferably 20 to 40 μm. It is.

  The substrate is not particularly limited as long as it is a substrate used in a normal solution casting method. For example, a substrate made of plastic or metal is used, and preferably a thermoplastic resin such as a polyethylene terephthalate (PET) film. A substrate made of is used.

  Examples of the solvent include non-protons such as N-methyl-2-pyrrolidone, N, N-dimethylformamide, γ-butyrolactone, N, N-dimethylacetamide, dimethylsulfoxide, dimethylurea, and dimethylimidazolidinone (DMI). Examples thereof include N-methyl-2-pyrrolidone, particularly from the viewpoint of solubility and solution viscosity. The said solvent may be used individually by 1 type, or may be used in combination of 2 or more type.

  Further, as a solvent for dissolving the sulfonic acid group-containing polyarylene, a mixture of the above aprotic polar solvent and alcohol may be used. Specific examples of alcohol include methanol, ethanol, propyl alcohol, iso-propyl alcohol, sec-butyl alcohol, tert-butyl alcohol and the like, and methanol is particularly preferable because it has an effect of lowering the solution viscosity in a wide composition range. . Alcohol may be used individually by 1 type, or may be used in combination of 2 or more type.

  When preparing the aromatic polymer electrolyte membrane, in addition to the polymer compound containing an acidic ion-conducting component, an inorganic acid such as sulfuric acid and phosphoric acid, an organic acid containing a carboxylic acid, an appropriate amount Water may be used in combination.

  In addition, when preparing an aromatic polymer electrolyte membrane, in addition to the polymer compound containing an acidic ion conductive component, the solvent and the organic acid, the acidic ion conductive component (sulfonic acid group) in the polymer and You may use together the additive which interacts. The additive added to the solution containing the sulfonic acid group-containing polyarylene is an organic or inorganic compound capable of forming an acid-base interaction with the sulfonic acid group-containing polyarylene, that is, a salt, and soluble in water or a polar solvent. Is selected.

<Joint>
Examples of the joining method in this step include hot pressing and hot rolling. In order to ensure uniform adhesion over the entire surface, hot pressing is preferable, and hot pressing should be performed under conditions of a temperature of 60 to 250 ° C., a pressure of 1 to 1000 kg / cm ² , and a pressing time of 1 to 60 minutes. Preferably, it is more preferable to perform hot pressing under the conditions of a temperature of 80 to 200 ° C., a pressure of 10 to 800 kg / cm ² , and a pressing time of 2 to 30 minutes, a temperature of 120 to 180 ° C., and a pressure of 100 to 600 kg / cm. ² , It is more preferable to perform hot pressing under conditions where the pressing time is 5 to 20 minutes.

[Step (D)]
In this step, if necessary, a plurality of structures cut out to a predetermined size from a structure composed of the electron conductive layer-electrode-electrolyte membrane-electrode-electron conductive layer and a plurality of current collectors are A laminated body is formed by alternately laminating and integrating so that the outside becomes a current collector. In this way, since a stacked body can be formed by cutting out a plurality of structures having a predetermined size from one structure, as compared to forming a stacked body by stacking structures one by one. Thus, variation in characteristics between structures can be reduced, and a laminate having uniform characteristics can be formed. What is necessary is just to adjust the magnitude | size, shape, etc. of the said cut-out structure according to the use of an electrochemical capacitor.

  The number of layers may be adjusted according to the thickness and capacity requirements of the electrochemical capacitor to be manufactured. Here, the number of stacked layers refers to the number of stacked structures when a structure composed of an electron conductive layer-electrode-membrane-electrode-electron conductive layer is regarded as one unit (hereinafter also referred to as “one cell”).

<Current collector>
Examples of the current collector include metal foils such as titanium, nickel, stainless steel, and niobium. Among these, titanium, stainless steel, and niobium are preferable from the viewpoint of stability such as cycle characteristics and change with time, and titanium and stainless steel are particularly preferable from the viewpoint of processability to foil and cost. The thickness of the current collector is preferably 5 to 100 μm, more preferably 10 to 80 μm, and still more preferably 10 to 50 μm.

<Joint>
Examples of the joining method in this step include hot pressing and hot rolling. In order to ensure uniform adhesion over the entire surface, hot pressing is preferable, and hot pressing should be performed under conditions of a temperature of 60 to 250 ° C., a pressure of 1 to 1000 kg / cm ² , and a pressing time of 1 to 60 minutes. Preferably, it is more preferable to perform hot pressing under the conditions of a temperature of 80 to 200 ° C., a pressure of 10 to 800 kg / cm ² , and a pressing time of 2 to 30 minutes, a temperature of 120 to 180 ° C., and a pressure of 100 to 600 kg / cm. ² , It is more preferable to perform hot pressing under conditions where the pressing time is 5 to 20 minutes.

[Step (E)]
In this step, the end of the laminate is cut as necessary so that a short circuit does not occur at the end of the laminate. Here, the end may be cut according to the use of the electrochemical capacitor, but it is preferable to cut off all the ends of the laminate from the viewpoint of preventing a short circuit.

Examples of the apparatus used for the excision include a dicing saw and a punching press.
[Step (F)]
In this step, if necessary, the laminate is immersed in hot water for water treatment. An electrochemical capacitor using a polymer electrolyte having proton conductivity is preferably treated with water to obtain a high output. Here, the temperature is preferably 20 to 90 ° C. and the immersion time is 1 to 300 minutes, more preferably the temperature is 50 to 90 ° C. and the immersion time is 5 to 200 minutes, and more preferably the temperature is 60 to 90. Water treatment is performed under the conditions of C and immersion time of 10 to 180 minutes.

[Step (G)]
In this step, if necessary, the laminate is immersed in a cleaning solution and subjected to ultrasonic cleaning for cleaning residues of electrode powder, metal, and the like remaining after the end of the laminate is excised. Here, the temperature is preferably 20 to 60 ° C. and the immersion time is 1 to 60 minutes, more preferably the temperature is 20 to 50 ° C. and the immersion time is 2 to 40 minutes, further preferably the temperature is 20 to 40. Ultrasonic cleaning is performed under the conditions of C and immersion time of 5 to 20 minutes.

In addition, examples of the cleaning liquid used for ultrasonic cleaning include water and alcohols such as methanol. Preferably, water is used.
The laminated body formed as described above exhibits good characteristics as an electrochemical capacitor. For example, an electrochemical capacitor is formed by being set and sealed in a sealing can. As the material of the sealing can, SUS can be used from the viewpoint of preventing corrosion by sulfuric acid. An electrochemical capacitor in which a predetermined number of cells are stacked and integrated in series exhibits a predetermined voltage according to the number of stacked layers, and has a feature as an electrochemical capacitor capable of large capacity and large current discharge. The number and the thickness of the electrochemical capacitor of the present invention can be adjusted according to the purpose of use, and can also be used for ultra-small chip capacitors, thin low resistance capacitors, and the like.

EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to these Examples. In the following examples, the sulfonation equivalent, molecular weight, and proton conductivity were determined as follows.

1. Measurement of Molecular Weight The molecular weight of polyarylene having no sulfonic acid group was determined by GPC using polystyrene (THF) as a solvent and the molecular weight in terms of polystyrene. The molecular weight of polyarylene having a sulfonic acid group was determined by GPC using polystyrene as a molecular weight using N-methyl-2-pyrrolidone (NMP) to which lithium bromide and phosphoric acid were added as an eluent.

2. Sulfonic acid equivalent The obtained polymer having a sulfonic acid group was thoroughly washed until the washing water became neutral to remove free remaining acid and dried. Next, a predetermined amount of polymer was weighed, and titration was performed using a standard solution of NaOH using phenolphthalein dissolved in a THF / water mixed solvent as an indicator, and the sulfonic acid equivalent was determined from the neutralization point.

3. Measurement of proton conductivity AC resistance is measured by pressing a platinum wire (diameter 0.5 mm) against the surface of a strip-shaped polymer electrolyte membrane sample with a width of 5 mm, holding the sample in a constant temperature and humidity device, and between the platinum wires It was obtained from AC impedance measurement. As specific conditions, impedance at AC 10 kHz was measured in an environment of 25 ° C. and relative humidity 100%. A chemical impedance measurement system manufactured by NF Circuit Design Block Co., Ltd. was used as the resistance measurement device, and JW241 manufactured by Yamato Scientific Co., Ltd. was used as the temperature and humidity control device. Five platinum wires were pressed at intervals of 5 mm, and the AC resistance was measured while changing the distance between the wires to 5 to 20 mm. As shown in the following formula, the specific resistance of the film was calculated from the distance between lines and the gradient of resistance.

Specific resistance R (Ω · cm) = 0.5 (cm) × film thickness (cm) × resistance-to-resistance gradient (Ω / cm)
AC impedance was calculated from the reciprocal of this specific resistance, and proton conductivity was calculated from this impedance.

<Synthesis Example 1>
To a 1 L three-necked flask equipped with a stirrer, thermometer, cooling pipe, Dean-Stark pipe and nitrogen-introduced three-way cock, 2,2-bis (4-hydroxyphenyl) -1,1,1,3 , 3,3-hexafluoropropane (bisphenol AF) 67.3 g (0.20 mol), 4,4′-dichlorobenzophenone (4,4′-DCBP) 60.3 g (0.24 mol), potassium carbonate 71 .9 g (0.52 mol), N, N-dimethylacetamide (DMAc) 300 mL, and toluene 150 mL were taken, heated in an oil bath under a nitrogen atmosphere, and reacted at 130 ° C. with stirring. When water produced by the reaction was azeotroped with toluene and reacted while being removed from the system with a Dean-Stark tube, almost no water was observed in about 3 hours. Most of the toluene was removed while the reaction temperature was gradually increased from 130 to 150 ° C., and the reaction was continued at 150 ° C. for 10 hours, and then 10.0 g of 4,4′-DCBP (0
. 040 mol) was added and the reaction was allowed to proceed for a further 5 hours. The resulting reaction solution was allowed to cool, and then the by-product inorganic compound precipitate was removed by filtration, and the filtrate was put into 4 L of methanol. The precipitated product was filtered and dried, and then dissolved in 300 mL of tetrahydrofuran. This was reprecipitated with 4 L of methanol to obtain 95 g (yield 85%) of the target compound.

The number average molecular weight (Mn) in terms of polystyrene determined by GPC (THF solvent) of the obtained compound was 11,200. The obtained compound was soluble in THF, NMP, DMAc, sulfolane and the like, and had a glass transition temperature (Tg) of 110 ° C. and a thermal decomposition temperature of 498 ° C. It was confirmed that the obtained compound was an oligomer represented by the following formula (I) (hereinafter also referred to as “BCPAF oligomer”).

<Synthesis Example 2>
In a 500 mL three-necked flask equipped with a stirrer, thermometer, condenser, Dean-Stark tube and nitrogen-introduced three-way cock, 4- [4- (2,5-dichlorobenzoyl) phenoxy] benzenesulfonic acid neo -39.58 g (98.64 mmol) of pentyl (A-SO ₃ neo-Pe), 15.23 g (0.136 mmol) of the BCPAF oligomer (Mn = 11,200) obtained in Synthesis Example 1, Ni (PPh ₃ ) 1.67 g (0.26 mmol) of ₂ Cl ₂ , 10.49 g (4.00 mmol) of PPh ₃ , 0.45 g of NaI (0.3
0 mmol), 15.69 g (24.0 mmol) zinc dust and 129 mL dry NMP were added under nitrogen. The reaction system was heated with stirring (finally heated to 75 ° C.) and allowed to react for 3 hours. The polymerization reaction solution was diluted with 250 mL of THF, stirred for 30 minutes, filtered using Celite as a filter aid, and the filtrate was poured into a large excess of 1500 mL of methanol to coagulate. The coagulated product was collected by filtration, air-dried, further redissolved in THF / NMP (200/300 mL each), and coagulated with 1500 mL of a large excess of methanol. After air drying, 47.0 g (yield 92%) of a copolymer (PolyAB-SO ₃ neo-Pe) composed of a sulfonic acid derivative protected with a target yellow fibrous neopentyl group was obtained by heat drying. The molecular weight by GPC was 47,600 for Mn (number average molecular weight) and 159,000 for Mw.

The obtained PolyAB-SO ₃ neo-Pe (5.1 g) was dissolved in NMP (60 mL).
Warmed to ° C. To the reaction system, a mixture of 50 mL of methanol and 8 mL of concentrated hydrochloric acid was added at a time to form a suspension, and the mixture was reacted for 10 hours under mild reflux conditions. A distillation apparatus was installed, and excess methanol was distilled off to obtain a light green transparent solution. This solution was poured into a large amount of water / methanol (1: 1 weight ratio) to solidify the polymer, and then the polymer was washed with ion-exchanged water until the pH of the washing water became 6 or more. From quantitative analysis of the IR spectrum and ion exchange capacity of the polymer thus obtained, the sulfonate group (—SO ₃ R) was quantitatively determined to be a sulfonate group (—S
O ₃ H) was found to be converted.

The molecular weight of the obtained sulfonic acid group-containing polymer by GPC was 53,200 for Mn, M
w was 185,000, and the sulfonic acid equivalent was 2.2 meq / g.
[Example 1]
The sulfonic acid group-containing polyarylene obtained in Synthesis Example 2 was dissolved in N-methyl-2-pyrrolidone, and a polymer electrolyte membrane having a dry film thickness of 40 μm was prepared by a casting method. When the proton conductivity of the obtained polymer electrolyte membrane was measured at 25 ° C. and 100% RH, it was 4.0 × 10 ⁻¹ Scm ⁻¹ .

  Next, conductive adhesive bunny height UCC (made by Nippon Graphite) was applied onto a 50 μm thick Teflon (registered trademark) sheet (Naflon tape, manufactured by Nichias Co., Ltd.) with a blade coater so that the coating thickness was 50 μm. And dried at 90 ° C. for 30 minutes to form an electron conductive layer.

Thereafter, ruthenium dioxide hydrate (manufactured by Aldrich) particles, acetylene black (manufactured by Denki Kagaku Kogyo Co., Ltd.), and sulfonic acid group-containing polyarylene obtained in Synthesis Example 2 were mixed with dimethoxyethane / water = 80/20 (weight ratio). And an ion conductive polymer binder dissolved in a mixture of particles) in a weight ratio of particles: acetylene black: binder = 1: 0.05: 0.10 to prepare an electrode paste.

Next, the electrode paste is applied onto the electron conductive layer with a blade coater so as to have a ruthenium dioxide hydrate amount of 5 mg / cm ² , dried at 90 ° C. for 60 minutes, and an electrode provided with a ruthenium dioxide hydrate layer -The electron conductive layer assembly was formed on the Teflon (registered trademark) sheet.

Next, the electrode-electron conductive layer assembly formed on the polymer electrolyte membrane and the Teflon (registered trademark) sheet was cut into 35 mm squares.
These were pressed for 5 minutes under a pressing condition of 160 ° C. and 200 kg / cm ² with the polymer electrolyte membrane sandwiched between the positive electrode and negative electrode electrode-electron conductive layer assembly, and then Teflon (registered trademark) on both sides. By peeling the sheet, a structure in which the electrolyte membrane-electrode interface was joined was obtained.

Next, the obtained structure was cut into four 15 mm squares. A state in which four of these structures and five current collectors of SUS foil having a 10 μm thick surface cut out in a 15 mm square are alternately stacked so that the outermost current collector is used. Then, pressing was performed for 10 minutes under a pressing condition of 160 ° C. and 400 kg / cm ² to form a laminated body in which capacitors of 4 cells were laminated in series.

Next, so as not to cause a short circuit at the end of the laminate, each of the four sides was cut with a dicing saw to form a 10 mm square, and immersed in hot water at 90 ° C. for 30 minutes for water treatment.
Further, ultrasonic cleaning was performed by immersing in water for cleaning the edge.

Excess water on the surface was removed, and the laminate was set in a SUS sealing can and sealed with a caulking device to form a 4-cell series capacitor.
Three capacitors ((a) to (c)) were formed by the same method and used for evaluation.

The following impedance evaluation was performed as the performance of the electrochemical capacitor.
A chemical impedance measurement system manufactured by NF Circuit Design Block Co., Ltd. was used as the impedance measurement device, and an impedance of 1 kHz was obtained as a capacitor impedance at a measurement voltage of 100 mV. Table 1 shows the evaluation results of the formed three capacitors ((a) to (c)).

  Moreover, in order to obtain | require the initial stage discharge capacity of a capacitor, charge / discharge at 0-3.4V was performed by charge / discharge current 1mA using the charge / discharge test machine MJ-201B by Hokuto Denko. Charging was performed for 3000 seconds, discharging was performed at a constant current, and the discharge capacity was determined from the discharge time. Table 1 shows the evaluation results of the three capacitors produced ((a) to (c)).

Moreover, in order to obtain the output performance of the capacitor, a charge / discharge tester MJ-201B manufactured by Hokuto Denko Co., Ltd. was used, and the charge / discharge current was 1 mA / cm ² , 5 mA / cm ² , 10 mA / cm ² , 20 mA /
Charging / discharging at 0-3.4V was performed at current densities of cm ² , 50 mA / cm ² , and 100 mA / cm ² , respectively. Charging is performed for a fixed time (1 mA / cm ² ; 3000 seconds, 5 mA / cm ² ; 600 seconds, 10 mA / cm ² ; 300 seconds, 20 mA / cm ² ; 150 seconds, 50 mA / cm ² ; 60 seconds, 100 mA / cm ² For 30 seconds), the battery was discharged at a constant current, and the capacity retention rate (relative value at each discharge current when the discharge capacity was 100% at 1 mA discharge) was evaluated. The evaluation results (average value of three capacitors) are shown in Table 1.

Subsequently, in order to evaluate reliability, evaluation by float charging at 70 ° C. was performed. Under an environment of 70 ° C., a voltage of 3.4 V was continuously applied, and after applying a voltage of 1000 hr, the impedance and discharge capacity at room temperature were evaluated in the same manner as described above, and the initial impedance and initial discharge capacity (10 mA discharge) ) As a standard, the degree of performance degradation was evaluated. The results are shown in Table 1.

[Example 2]
Thermoplastic elastomer Styrene-Ethylene-Butylene-Styrene Block Copolymer (SEBS) / Ketjen Black = 100/30 (weight ratio) A paste made of 5% toluene solution is used so that the coating thickness is 25 μm. The surface was coated on a polyester film coated with a fluororesin with a coater and dried at 90 ° C. for 15 minutes to form an electron conductive layer.

  Thereafter, ruthenium dioxide hydrate (manufactured by Aldrich) particles, acetylene black (manufactured by Denki Kagaku Kogyo Co., Ltd.), and sulfonic acid group-containing polyarylene obtained in Synthesis Example 2 were mixed with dimethoxyethane / water = 80/20 (weight ratio). And an ion conductive polymer binder dissolved in a mixture of particles) in a weight ratio of particles: acetylene black: binder = 1: 0.10: 0.10 to prepare an electrode paste.

Next, the electrode paste is applied on the electron conductive layer with a blade coater so as to have a ruthenium dioxide hydrate amount of 1 mg / cm ² , dried at 90 ° C. for 60 minutes, and an electrode provided with a ruthenium dioxide hydrate layer -An electron conductive layer assembly was formed on the polyester film.

Thereafter, a 4-cell series capacitor was formed in the same manner as in Example 1 and used for evaluation. The evaluation results are shown in Table 1.
[Comparative Example 1]
A polymer electrolyte membrane / electrode-electron conductive layer assembly obtained in the same manner as in Example 1 was cut into a 15 mm square. Then, the Teflon (trademark) sheet | seat of the base material was peeled from the electrode-electron conductive layer assembly. Next, each member is stacked in the order and number of sheets that can form a 4-cell series capacitor in the order of current collector, electrode-electron conductive layer assembly, polymer electrolyte membrane, electrode-electron conductive layer assembly, and current collector. After that, pressing was performed for 10 minutes under a pressing condition of 160 ° C. and 400 kg / cm ² to form a laminated body in which capacitors of 4 cells were laminated in series.

  Thereafter, in the same manner as in Example 1, after cutting, water-containing treatment, and ultrasonic cleaning, it was set in a SUS sealing can to form a 4-cell series capacitor for evaluation and used for evaluation. The evaluation results are shown in Table 1.

[Comparative Example 2]
An electrode paste prepared in the same manner as in Example 1 was applied to one or both surfaces of a 30 μm-thick titanium foil to form an electrode layer directly on the current collector, and the current collector-electrode assembly and electrode- A current collector-electrode assembly was obtained. After drying these joined bodies, they were cut into 15 mm squares. Thereafter, these laminates were similarly cut into 15 mm squares, and together with a polymer electrolyte membrane and a current collector, a current collector-electrode assembly, a polymer electrolyte membrane, an electrode-current collector-electrode assembly, and a polymer electrolyte. After stacking each member in the order and number of sheets so that a 4-cell series capacitor can be constructed in the order of film and current collector, the 4-cell capacitor is heated for 10 minutes at 160 ° C. and 400 kg / cm ² press condition. Were laminated in series to form an integrated laminate.

  Thereafter, in the same manner as in Example 1, after cutting, water-containing treatment, and ultrasonic cleaning, it was set in a SUS sealing can to form a 4-cell series capacitor for evaluation and used for evaluation. The evaluation results are shown in Table 1.

[Comparative Example 3]
An electrode paste prepared in the same manner as in Example 2 was formed on a Teflon (registered trademark) sheet, but when dried at 90 ° C. for 60 minutes, fine cracks occurred and peeled off, creating a series capacitor. could not.

Claims (6)

Applying an electron conductive layer paste on a release sheet to form an electron conductive layer;
Applying an electrode paste on the electron conductive layer to form an electrode-electron conductive layer assembly;
After sandwiching and bonding the aromatic polymer electrolyte membrane with the obtained pair of electrode-electron conductive layer assembly, the release sheet was peeled off, and the electron conductive layer-electrode-electrolyte membrane-electrode-electron conduction And a step of forming a structure composed of layers. The aromatic polymer electrolyte membrane is a sulfonic acid group-containing polyarylene containing a structural unit represented by the following formula (A) and a structural unit represented by the following formula (B). Item 2. A method for producing an electrochemical capacitor according to Item 1.

[In the formula (A), Y represents —CO—, —SO ₂ —, —SO—, —CONH—, —COO—, — (
CF ₂ ) _i — (i represents an integer of 1 to 10) and at least one structure selected from the group consisting of —C (CF ₃ ) ₂ —,
Z is a direct bond, or at least one selected from the group consisting of — (CH ₂ ) _j — (j represents an integer of 1 to 10), —C (CH ₃ ) ₂ —, —O—, and —S—. Show the structure of the species,
Ar is an aromatic having a substituent represented by —SO ₃ H, —O (CH ₂ ) _p SO ₃ H or —O (CF ₂ ) _p SO ₃ H (p represents an integer of 1 to 12). Group,
m shows the integer of 0-10, n shows the integer of 0-10, k shows the integer of 1-4. ]

[In the formula (B), A and D are each independently a direct bond, or —CO—, —SO ₂ —,
—SO—, —CONH—, —COO—, — (CF ₂ ) _i — (i represents an integer of 1 to 10), — (CH ₂ ) _j — (j represents an integer of 1 to 10). ), —CR ′ ₂ — (R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group), a cyclohexylidene group, a fluorenylidene group, —O— and —S—. At least one structure selected from the group, B is independently an oxygen atom or a sulfur atom,
R ^{1 to} R ¹⁶ may be the same as or different from each other, and are a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group partially or wholly halogenated, an allyl group, an aryl group, a nitro group, and a nitrile group. At least one atom or group selected from the group consisting of
s represents an integer of 0 to 4, t represents an integer of 0 to 4, and r represents 0 or an integer of 1 or more. ]   The method for producing an electrochemical capacitor according to claim 1, wherein the electrode paste contains ruthenium dioxide hydrate.   The method for producing an electrochemical capacitor according to claim 1, wherein the application surface of the release sheet is a fluorine material exhibiting releasability.   A plurality of structures and a plurality of current collectors cut out to a predetermined size from a structure composed of the electron conductive layer-electrode-electrolyte membrane-electrode-electron conductive layer so that the outermost portion is a current collector. The method for producing an electrochemical capacitor according to claim 1, further comprising a step of forming a laminated body that is alternately laminated and integrated.   The method for producing an electrochemical capacitor according to claim 5, further comprising a step of immersing the laminate in hot water to perform a water treatment.