WO2007125924A1 - Binder for electrochemical cell electrode - Google Patents

Abstract

Disclosed is a binder for electrochemical cell electrodes which is composed of an emulsion composition wherein resin particles each composed of an olefin polymer (A) and an acrylic polymer (B) having an internally crosslinked structure are dispersed in water. The binder for electrochemical cell electrodes exhibits sufficient adhesion to a metal collector, a positive electrode active material and a negative electrode active material, and enables to improve high-rate discharge characteristics and cycle characteristics.

Description

 Specification

 Binder for electrochemical cell electrode

 Technical field

 [0001] The present invention relates to a binder for an electrochemical cell electrode comprising an aqueous emulsion composition containing an olefin polymer and an acrylic polymer.

 Background art

 [0002] Electrochemical cells such as secondary batteries and electrochemical double layer capacitors are used in various fields. Secondary batteries that can be used repeatedly by charging are widely used, for example, as power sources for cordless electronic devices such as mobile phones, notebook computers, and power tools, and as power sources for driving automobiles such as environmentally friendly hybrid vehicles. Alkaline secondary batteries (Ni-MH batteries) obtained using hydrogen storage alloys, non-aqueous electrolyte secondary batteries (lithium ion batteries) using lithium compounds, and the like have been put into practical use. The electric double layer capacitor is an electronic component that has been widely used in various fields such as the electronics industry, home appliances, and automobiles as a backup power source for ICs, LSI memories, and actuators. In recent years, expectations for improving the performance of electrochemical cells such as secondary batteries and electric double layer capacitors are increasing.

 [0003] Positive and negative electrodes of secondary batteries such as Ni_MH batteries and lithium ion batteries are produced by binding each active material for positive and negative electrodes to a current collector with a binder.

 [0004] In addition, the positive and negative electrodes of the electric double layer capacitor use activated carbon as the positive and negative electrode active materials, and like the secondary battery, the active materials for positive and negative electrodes are bound to the metal current collector by the binder. It is produced by making it.

 [0005] Various resin compositions have heretofore been used as binders for these electrodes. As an example of a lithium ion battery, a positive electrode binder is a solution of polyvinylidene fluoride (PVDF) dissolved in N-methyl-2-pyrrolidone (NMP) or an aqueous dispersion of polytetrafluoroethylene (PTFE). PVDF or styrene-butadiene rubber (SBR) aqueous dispersion (Patent Document 1) is used as the binder for the negative electrode.

[0006] Fluorocarbon resins such as PVDF and PTFE have low adhesion to active materials and metal current collectors . Therefore, it is necessary to add a large amount as a binder, and there is a problem of covering the surface of the active material and deteriorating battery characteristics. In addition, since the fluororesin has low adhesion to the active material and metal current collector, repeated charging and discharging of the secondary battery and capacitor will cause the active material to fall out of the metal current collector, reducing the battery capacity. There is a problem to make.

 [0007] In addition, since SBR has a double bond in the main chain, when used for the positive electrode, repeated charge and discharge of the secondary battery and capacitor causes the double bond portion to undergo oxidative degradation, and the active material becomes a metal collection. There is a problem that the electric power drops off and the capacity of the battery and capacitor decreases. In addition, when used in the negative electrode, since the swelling property with respect to the electrolyte is high, there is a problem that the high rate discharge characteristics and the cycle characteristics deteriorate due to the loss of contact with the active material and the current collector.

 [0008] In order to solve such a problem, an investigation has been made to use an olefin-based polymer that is electrochemically stable and has a low swelling property with respect to an electrolytic solution (Patent Document 2) as an active material. In addition, the adhesion to metal current collectors is still not sufficient. As means for improving the adhesive strength, a method of copolymerizing an olefin monomer and an acrylate ester or methacrylate ester monomer (Patent Document 3), and a method of adding an acrylic resin to olefin (Patent Document 3) 4) is disclosed, but the acrylic resin part swells with respect to the electrolyte solvent, so that the contact with the active material and the current collector is lost, and the battery and capacitor characteristics are deteriorated. In the latter case, the binder is aggregated in the paste for forming the electrode, so that a large amount of surfactant needs to be added, and there is a problem that a large amount of the free surfactant in the paste deteriorates the battery characteristics. Therefore, the adhesion to the active material and the metal current collector, the high-rate discharge characteristics and cycle characteristics of the secondary battery, and the electrostatic capacity and internal resistance of the electric double layer capacitor were still insufficient.

 Patent Document 1: Japanese Patent No. 3101775

 Patent Document 2: JP 2002-251998

 Patent Document 3: Japanese Unexamined Patent Publication No. 2005-63735

 Patent Document 4: Japanese Unexamined Patent Application Publication No. 2004-327064

 Disclosure of the invention

 Problems to be solved by the invention

[0009] The present invention provides sufficient adhesion to a metal current collector, a positive electrode active material, and a negative electrode active material. The present invention provides a binder for an electrochemical cell electrode that can improve the high rate discharge characteristics, cycle characteristics, and capacitance of the electrochemical cell and reduce the internal resistance. Means for solving the problem

 [0010] As a result of intensive studies on the above-mentioned problems of the prior art, the present inventors have found that a binder for an electrochemical cell electrode comprising the following emulsion composition can solve these problems. Completed. That is, the present invention is specified by the items described below.

 [0011] (1) A binder for an electrochemical cell electrode comprising an emulsion composition in which resin particles formed from an olefin polymer (A) and an acrylic polymer (B) having an internally crosslinked structure are dispersed in water .

 [2] (2) Acrylic polymer with internal cross-linked structure (B) Acrylic monofunctional monomer (b

 1) The binder for an electrochemical cell electrode according to (1), which is produced from a monomer containing a polyfunctional monomer (b-2).

 [0013] (3) Acrylic polymer (B) having an internal cross-linked structure is composed of an acrylic monofunctional monomer (b—12) having a reactive group, the acrylic monomer (b— (1) The binder for an electrochemical cell electrode according to (1), which is produced from a compound containing the compound (c) having two or more groups capable of reacting with the reactive group of 2).

 [0014] (4) The acrylic monofunctional monomer (b-12) having the reactive group is a reactive lpoxyl group and / or a hydroxyl group, and the acrylic group of the compound (c) The binder for an electrochemical cell electrode according to (3), wherein the group that reacts with the reactive group of the system monomer (b — 1 — 2) is an epoxy group.

 [0015] (5) An acrylic polymer (B) having an internal cross-linked structure is formed from an allylic monofunctional monomer (b-1 1 2) having a reactive group (1), a reactive group (1 The binder for electrochemical cell electrodes according to (1), which is produced from a monomer containing an acrylic monofunctional monomer having a reactive group (2) that reacts with (2).

 [0016] (6) The electrochemistry according to any one of (1) to (5), wherein the olefin polymer (A) comprises a copolymer of an olefin monomer (a-1) Cell electrode binder.

[0017] (7) The olefin polymer (A) comprises an olefin monomer (a-1) and an olefin monomer. The binder for an electrochemical cell electrode according to any one of (1) to (6), which contains a copolymer of another monomer (a-2) that can be copolymerized.

[0018] (8) The ratio of the olefin-based monomer (a-1) to the other monomer (a_2) copolymerizable with the olefin-based monomer is (a_l) and (a_2) (A_l) force S99. 9-35.0% by weight, (a-2) is 0.1-65.0% by weight based on the total weight, and the electrochemical cell electrode bar according to (7). Inder.

 [9] (9) Based on the total weight of the olefin polymer (A) and the acrylic polymer (B) in the emulsion, the olefin polymer (A) is 95 to 30% by weight, and the acrylic polymer ( The binder for electrochemical cell electrodes according to any one of (1) to (8), wherein B) is 5 to 70% by weight.

 [0020] (10) An electrode comprising the binder according to any one of (1) to (9).

[0021] (11) An electrochemical cell using the electrode according to (10) as a positive electrode and / or a negative electrode.

[0022] (12) The electrochemical cell according to (11), wherein the electrochemical cell is a secondary battery.

[0023] (13) The electrochemical sensor according to (11), wherein the electrochemical cell is an electric double layer capacitor.

 The invention's effect

 [0024] According to the present invention, an electrochemical cell electrode that has sufficient adhesion to a metal current collector, a positive electrode active material, and a negative electrode active material, and can improve high rate discharge characteristics and cycle characteristics. A binder can be obtained.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0025] The present invention is described in detail below.

[0026] Olefin polymer (A)

 The olefin polymer used in the present invention is a homopolymer of an olefin monomer (a-1), a copolymer of an olefin monomer (a-1), an olefin monomer (a—). It is a copolymer with other monomer (a-2) that can be copolymerized with 1).

[0027] The olefin-based monomer (a-1) is not particularly limited, and examples thereof include ethylene, propylene, 1-butene, 1 pentene, 1-hexene, 4-methinole 1 pentene.

1-pentene, 1-heptene, 1-hexene, 1-decene, 1-dodecene Conjugated gens such as α-olefin, butadiene, ethylidene norbornene, dicyclopentagen, 1,5-hexagen, and the like. These monomers can be used alone or in combination of two or more.

 [0028] The other monomer (a-2) copolymerizable with the olefin monomer (a-1) is not particularly limited as long as it is copolymerizable, Examples include styrene, methyl acrylate, methyl methacrylate, butylacetate, butyalcohol, and unsaturated carboxylic acids such as maleic acid, acrylic acid, and methacrylic acid. These monomers can be used alone or in combination of two or more.

 [0029] Among these, ethylene and propylene are used as the monomer (a_l), and maleic acid, acrylic acid, methacrylic acid S as the monomer (a_2), and cycle characteristics of the electrochemical cell. From the point of view, it is preferable.

 [0030] Specific examples of the homopolymer of the olefin-based monomer (a-1) and the copolymer of the olefin-based monomer (a-1) include low-density polyethylene, high-density polyethylene, polypropylene, polymer, and the like. 1-butene, poly-3-methyl-1-butene, poly-4-methyl-1-pentene, ethylene / propylene copolymer, ethylene / 1-butene copolymer, propylene / 1-butene copolymer Polymer, propylene · 1-butene 'ethylene copolymer, propylene, 1-butene, 3-methyl 1-butene, 4-methyl 1-pentene, 3-methyl- 1-pentene, 1 heptene Α-olefin polymers such as 1-hexene, 1-decene and 1-dodecene; α-olefin gen copolymers such as ethylene 'butadiene copolymer and ethylene'ethylidene norbornene copolymer ; Echi Two or more types of monoolefins such as ethylene 'propylene' butadiene terpolymer, ethylene propylene ethylidene norbornene terpolymer, ethylene 'propylene 1,5_hexagen terpolymer, etc. And copolymers with Jen.

 Among these, ethylene / propylene copolymer and propylene / 1-butene copolymer are preferable from the viewpoint of cycle characteristics of the electrochemical cell.

[0032] Specific examples of the copolymer of the olefin-based monomer (a-1) and the other monomer (a-2) that can be copolymerized include ethylene 'Butyl acetate copolymer, ethylene' Ethylene.unsaturated carboxylic acid copolymers such as butyl alcohol copolymer and ethylene 'methacrylic acid copolymer And propylene'maleic anhydride copolymer.

 [0033] Among these, ethylene.unsaturated carboxylic acid copolymers such as ethylene'methacrylic acid copolymer and propylene'maleic anhydride copolymer are preferable in view of cycle characteristics of the electrochemical cell.

 [0034] In the case of a copolymer of the olefin monomer (a-1) and another monomer (a-2) copolymerizable with the olefin monomer (a-1), the olefin monomer (a_1) and olefin The ratio of the other monomer (a_ 2) that can be copolymerized with the monomer based on the total weight of (a_ l) and (a_ 2) is usually 99.9 ~ 35.0 wt%, (a_2) is 0. 65.0 wt%, preferably (a_l) is 99.9-50 wt%, (a_2) is 0.1-50 wt% More preferably, (a_l) is 99.9 to 70% by weight and (a_2) is 0.1 to 30% by weight. When the ratio of (a_1) to (a_2) is in the above range, the characteristics as olefins are expressed, the electrochemical stability can be maintained, and when the electrochemical cell characteristics are deteriorated, there is no problem. Les.

 [0035] The olefin-based polymer (A) can be used alone or in combination of two or more.

 [0036] Acrylic polymer (B)

 In the present invention, the acrylic polymer (B) is characterized by having an internal cross-linked structure.

 [0037] As described above, the binder for an electrochemical cell electrode containing the acrylic polymer (B) having an internally cross-linked structure is suppressed from swelling with respect to the electrolyte solvent, and further, the metal current collector, the positive electrode active material, and the negative electrode Sufficient adhesion to the active material.

[0038] The method for producing the acrylic polymer (B) having an internally crosslinked structure is not particularly limited, but the acrylic monofunctional monomer (b-1) and the polyfunctional monomer (b- 2) A method for producing an acrylic polymer (B) from a monomer containing the above (hereinafter, the polymer obtained by this production method is also referred to as an acrylic polymer (B1)), which has a reactive group An acrylic monofunctional monomer (b-1 1 2) and a compound (c) having two or more groups that react with the reactive group of the acrylic monomer (b-1 1 2) A method for producing an acrylic polymer (B) from a compound containing the same (hereinafter, the polymer obtained by this production method is also referred to as an acrylic polymer (B2)), an acrylic monofunctional monomer having a reactive group The monomer (b-1 1 2) is polymerized using two or more monomers, and the reactive groups of the monomer (b-1 1 2) are reacted with each other. System polymerization And a method of producing the body (B) (hereinafter, the polymer obtained by this production method is also referred to as an acrylic polymer (B3)).

 [0039] The acrylic polymer (B) of the present invention is produced from a monomer containing at least an acrylic monofunctional monomer (b-1).

[0040] The acrylic monofunctional monomer (b-1) includes an acrylic monofunctional monomer ( _b 1 1 _; L) having no reactive group and an acrylic monofunctional monomer having a reactive group. It is classified as a monofunctional monomer (b— 1 1 2). In the acrylic polymer (B2), the reactive group in the acrylic monofunctional monomer (b 1 1) is a group that the compound (c) described later has, for example, a group that reacts with an epoxy group. That means.

 [0041] In the acrylic polymer (B3), two or more of the above-mentioned acrylic monofunctional monomers (b_l) are used, and the two monomers include the reactive group. There is no particular limitation as long as they react with each other. For example, when one monomer (b_l) has an epoxy group, a monomer having a carboxyl group can be used as the other monomer (b-1).

 [0042] As the acrylic monofunctional monomer (b-11) having no reactive group, methyl acrylate, ethyl acrylate, n-butyl acrylate, i-butyl acrylate, acrylic acid 2- Alkyl (meth) acrylates such as ethyl hexyl, lauryl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate; acrylamide, Examples include N-alkyl-substituted (meth) acrylamides such as methacrylamide, N, N dimethylacrylamide, N, N jetylacrylamide, and N-isopropylacrylamide.

 [0043] The monomers (b-11) can be used singly or in combination of two or more.

 [0044] The acrylic monofunctional monomer (b-12) having a reactive group may be any acrylic monofunctional monomer having a group that reacts with the compound (c) described later. There is no particular limitation.

[0045] For example, when the compound (c) is a compound having an epoxy group, an acrylic monofunctional monomer having a carboxyl group such as acrylic acid or methacrylic acid, hydroxyethyl propyl methacrylate, etc. Hydroxyl groups represented by hydroxyalkyl (meth) atalylate Examples thereof include acrylic monofunctional monomers.

 [0046] In the production of the acrylic polymer (B3), a carboxyl group such as acrylic acid or methacrylic acid is used as one of the acrylic monofunctional monomers (b-12) having a reactive group. When an acrylic monofunctional monomer having an epoxy group is used, an acrylic monofunctional monomer having an epoxy group, such as glycidino raretailate or glycidyl methacrylate, is used as a monofunctional monomer. It can be used as another kind of (b_1-2).

 [0047] The above monomers (b_l_2) can be used singly or in combination of two or more.

 [0048] In addition to the acrylic monofunctional monomer (b-1) described above, the polyfunctional monomer (b_2), that is, the above-described acrylic polymer (B1), Use monomers with two or more vinyl groups. Specific examples of monomers having two or more bur groups include ethylene glycolonoresyl methacrylate, propylene glycolonoresimethacrylate, diethylene glycol ditalylate, triethylene glycol ditalylate, tetraethylene glycol ditalylate, divinyl. Examples include benzene.

 [0049] The monomer (b-2) may be used alone or in combination of two or more.

 [0050] For the production of the above-mentioned acrylic polymer (B2), in addition to the above-mentioned acrylic monofunctional monomer having a reactive group, the acrylic monofunctional monomer (b-12), The compound (c) having two or more groups that react with the reactive group of the acrylic monomer (b-12) is used.

 [0051] As a group that reacts with the acrylic monomer (b-12), when the reactive group of the monomer (b-12) is, for example, a hydroxyl group or a carboxyl group, an epoxy is used. Group, carbodiimide group, oxazoline group and the like Among these groups, an epoxy group is preferable from the viewpoint of reaction rate.

[0052] Examples of the compound (c) having two or more epoxy groups include glycidyl ether compounds such as bisphenol 1 type A epoxy resin and phenol novolac type epoxy resin, darisidyl ester compounds, and glycidylamine compounds. Etc. Among these compounds, diglycidyl ether compounds such as bisphenol-A type epoxy resins are preferred from the viewpoint of reaction rate. [0053] Examples of commercially available products of the diglycidinole ether compound include epomic (manufactured by Mitsui Chemicals, Inc.).

 [0054] The compound (c) can be used singly or in combination of two or more.

[0055] By using such a compound, the ability to produce acrylic polymers (B1) and (B2) can be achieved.

 [0056] When the acrylic polymer (B2) is produced, it is possible to use an acrylic monofunctional monomer (b_l_2) having a reactive group and the compound (c). Even if necessary, an acrylic monofunctional monomer (b_ l _ l) that does not have a reactive group and a polyfunctional monomer (b-2) can be used if necessary. Yo!

 [0057] Further, in the production of the above-mentioned acrylic polymer (B3), two or more kinds of acrylic monofunctional monomers (b_l_2) having a reactive group are used. The acrylic polymer (B3) can be produced by polymerizing these monomers (b_l_2) and reacting the reactive groups of the monomer (b_l_2). Therefore, in producing the acrylic polymer (B3), one monomer (b—12) having a reactive group (1) and a reactive group that reacts with the reactive group (1). It is necessary to use another monomer (b-1-2) having (2). For example, an acrylic monofunctional monomer having a carboxyl group such as acrylic acid or methacrylic acid is used as the acrylic monofunctional monomer (b-12) having a reactive group (1). In this case, an acrylic monofunctional monomer having an epoxy group, such as glycidyl acrylate or glycidyl methacrylate, is converted into a monofunctional monomer (b— 1 2) having a reactive group (2). Can be used as

 [0058] When the acrylic polymer (B3) is produced, as described above, the acryl-based monofunctional monomer (b-1-12) having the reactive group (1), the reactive group It is necessary to use another monomer having (2) (b-1 -2), but if necessary, an acrylic monofunctional monomer having no reactive group (B— 1 1 1), attalinole monofunctional monomers (b— 1 1 2) having other reactive groups, and polyfunctional monomers (b— 2) may be used. Les.

 [0059] Reactive groups contained in other acrylic monofunctional monomers having reactive groups

(3) may be a group that reacts with both the reactive group (1) and the reactive group (2), or may be a group that reacts with one of them, or both. No, no response to any deviation It may be.

 [0060] Further, in the production of the acrylic polymer (B), a non-acrylic monomer having a reactive group (b) that can be copolymerized with the acrylic monofunctional monomer (b-1). — You can use 3). Examples of the monomer (b_3) include a carboxyl group such as crotonic acid, itaconic acid, fumaric acid, and maleic acid when the compound (c) is a compound having an epoxy group. Monomer. For example, when the acrylic polymer (B2) is produced using the compound (c) having an epoxy group, the internal crosslinking structure is further controlled by further using the monomer (b_3). be able to.

 [0061] Also, for example, when producing an acrylic polymer (B3), an acrylic monofunctional monomer (b-12) having an epoxy group as a reactive group is used. When the acrylic polymer (B3) is produced, the internal crosslinking structure can be further controlled by further using the monomer (b_3).

 [0062] The monomer (b-3) may be used alone or in combination of two or more.

 [0063] Further, in producing the acrylic polymer (B), another monomer (b-4) copolymerizable with the acrylic monofunctional monomer (b-1) is used. May be.

[0064] Examples of the monomer (b-4) include polar group-containing monomers such as acrylonitrile and methacrylonitrile; aromatic monomers such as styrene and _α -methylstyrene. However, the above monomer (b-4) excludes olefin-based monomers such as ethylene, propylene and 1-butene.

 [0065] The monomer (b-4) can be used singly or in combination of two or more.

[0066] In the acrylic polymer (B1), an acrylic monofunctional monomer (b-1), a polyfunctional monomer (b-2), and a monomer (b) used as necessary Based on the total weight of b-3) and (b-4), the usual amounts of use are (b_l) 10-99.5 wt%, (b_2) 0.5-30 wt% (B_3) is 0 to 60% by weight, and (b_4) is 0 to 60% by weight. When the amount used is in the above range, the resulting binder has a tendency to be less swellable with respect to the electrolyte while maintaining adhesion to the electrode, and the binder was used. The battery characteristics of the battery tend to be lower.

 [0067] In the acrylic polymer (B2), an acrylic monofunctional monomer having a reactive group

 (b— 1 2), compound (c), acrylic monofunctional monomer without reactive groups (b— 1 1 1), polyfunctional monomer (b) — 2), based on the total weight of monomers (b—3) and (b _4), the normal usage amount of each is _ 1 _ 2) 1 to 70% by weight, (b_ l _ l) Is 0 to 98.5 wt%, (b_2) is 0 to 50 wt%, (b_3) is 0 to 50 wt%, (b_4) is 0 to 50 wt%, and compound (c) is 0.5 to 0.5 wt% 30% by weight. When the amount used is within the above range, the resulting binder has a tendency to be less swellable with respect to the electrolyte while maintaining adhesion to the electrode, and the battery characteristics of the battery using the binder are as follows. There is a tendency not to lower.

 In addition, in the acrylic polymer (B3), an acrylic monofunctional monomer (b_l_2) having a reactive group and an acrylic monofunctional monomer having no reactive group, which is used as necessary. Based on the total weight of monomer (b— 1 1), multifunctional monomer (b— 2), monomer (b— 3) and (b— 4), , (B-1 2) is 1 to: 100 wt%, (b-1 1) is 0 to 99 wt%, (b-2) is 0 to 50 wt%, (b-3) is 0 to 50 wt% %, (B-4) is 0 to 50% by weight. When the amount used is in the above range, the resulting binder has a tendency to be less swellable with respect to the electrolyte while maintaining adhesion to the electrode, and the battery characteristics of the battery using the binder are more significant. There is a tendency not to decrease.

[0068] The initiator used in the polymerization of the acrylic polymer (B) is not particularly limited as long as the above-mentioned monomer can be polymerized. As specific examples of the initiator used in the polymerization of the acrylic polymer (B), for example, any initiator generally used in emulsion polymerization can be used. Typical initiators used in emulsion polymerization include persulfates such as persulfate, ammonium persulfate; tamenno, id-peroxide, t_petit-norehydride peroxide, benzoyl peroxide, t_ Organic peroxides such as butyl peroxide _ 2_ethylhexanoate, t_butyl peroxybenzoate, lauroyl peroxide; azo compounds such as azobisisoptyronitrile; or these persulfates, organic peroxides Zo compounds, metal ions such as iron ions, sodium sulfoxylate, honolemuanolide, sodium pyrosulfite, sodium bisulfite, L-asco And redox initiators in combination with reducing agents such as rubic acid and Rongalite. These initiators can be used alone or in combination of two or more.

[0069] In addition, the molecular weight of mercaptans such as t-decyl mercaptan and n-dodecyl mercaptan, and aryl compounds such as allylic sulfonic acid, methallylic sulfonic acid and soda salts thereof are adjusted as necessary. It can be used as an agent.

[0070] In the emulsion composition of the present invention, resin particles formed from an olefin polymer (A) and an acrylic polymer (B) having an internal cross-linked structure are dispersed in water.

[0071] In the present invention, an olefin polymer (A) and an acrylic polymer are placed inside the resin particles.

 (B) may be an emulsion composition composed of resin particles containing both, and resin particles composed of an olefin polymer (A) and resin particles composed of an acrylic polymer (B). The emulsion composition to contain may be sufficient. Further, the resin particles that are the constituent components of the emulsion composition may be composed of a single type of polymer, or may be a mixture of two or more types of polymers.

[0072] Among the emulsion compositions according to the present invention, the emulsion composition containing the olefin polymer (A) and the acrylic polymer (B) in the same particle is the particles of the olefin polymer (A). Is produced by polymerizing the acrylic polymer (B) from the monomers and compounds described above using the initiator in the presence of emulsion dispersed in water. During this polymerization, an acrylic polymer (B) is formed in the resin particles containing the olefin polymer (A).

 [0073] Among the emulsion compositions according to the present invention, the emulsion composition containing the resin particles made of the olefin polymer (A) and the resin particles made of the acrylic polymer (B) is usually used in an emulsion polymerization method. To produce an acrylic polymer (B) emulsion from the initiator, monomer, and compound, and the resulting acrylic polymer (B) emulsion and olefin polymer (A) are water. Manufactured by mixing the emulsion dispersed in

[0074] The olefin-based emulsion in which the particles of the olefin-based polymer (A) are dispersed in water is not particularly limited by its production method. For example, a melted resin can be forcibly broken by stirring in water or an extruder. For example, adding water to the molten and kneaded resin. As shown in Japanese Patent Publication No. 42-000275, Japanese Patent Publication No. 7-008933, etc.

 [0075] In order to improve the stability of the particles when the acrylic polymer (Β) is polymerized in the presence of the emulsion of the olefin-based polymer (、), or when the acrylic polymer (Β) alone is produced. It is also possible to use a surfactant used in a usual emulsion polymerization method. Specific examples of the surfactant include an anionic surfactant, a nonionic surfactant, a cationic surfactant, and other reactive surfactants. These surfactants can be used singly or in combination of two or more.

 [0076] Specific examples of the nonionic surfactant include, for example, polyoxyethylene lauryl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene oxyphenyl ether, and polyoxyethylene noluyl phenyl ether. Oxyethylene 'oxypropylene block copolymer, tert-octylphenoloxyl polyethoxyethanol, nonylphenoloxyl polyethoxyethanol and the like.

 [0077] Specific examples of the anionic surfactant include sodium dodecylbenzenesulfonate, sodium lauryl sulfate, sodium alkyldiphenyl ether sulfonate, sodium alkylnaphthalene sulfonate, sodium dialkylsulfosuccinate, stearic acid. Sodium, potassium oleate, sodium dioctyl sulfosuccinate, sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate sodium dialkyl sulfosuccinate, sodium tert-octylphenoxyethoxypolyethoxy ether sulfate, etc. Is mentioned.

 Specific examples of the cationic surfactant include lauryl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, and the like.

[0078] The amount of the surfactant used is not particularly limited, but when producing an emulsion composition in which the olefin polymer (A) and the acrylic polymer (B) are contained in the same particle. If the amount of the surfactant used is increased, particles consisting only of the acrylic polymer (B) are produced. In addition, when the amount of the surfactant used is large, the amount of the surfactant released in the obtained binder is relatively increased, resulting in deterioration of the electrochemical cell characteristics. Therefore, the acrylic polymer (B) is polymerized in the presence of the olefin polymer (A) emulsion. When the acrylic polymer (B) is polymerized alone, the amount of the surfactant used is the monomer (b-1), (b—) used for the acrylic polymer (B). It is preferably 0 to 5% by weight based on the total weight of 2), (b-3), (b-4) and compound (c).

 [0079] When producing an emulsion composition in which the olefin polymer (A) and the acrylic polymer (B) are contained in the same particle, the resin particles comprising the olefin polymer (A) and the acrylic polymer are used. Even in the case of producing an emulsion composition containing resin particles comprising the polymer (B), the various monomers and compounds described above are batched or divided, and a certain layer is continuously dropped. And you can get it.

 [0080] The acrylic polymer (B) is polymerized at a temperature of usually 0 to 100 ° C, preferably 30 to 90 ° C, in the presence of the initiator.

 [0081] The form of the resin particles constituting the emulsion composition is not particularly limited. For example, for emulsions containing an olefin polymer (A) and an acrylic polymer (B) in the same particle, the shape of the particle may be a core / shell structure, a composite structure, a localized structure, or a dharma shape. Examples include a structure and a raspberry structure.

 [0082] In the present invention, the weight average particle diameter of the resin particles constituting the emulsion composition (Mic rotrac UPA: measured by Honneywell) is preferably 10 nm to 10 / im, more preferably 10 nm to 2 / im. When the particle diameter exceeds 10 / im, the adhesive strength with the active material and the metal current collector is reduced, and the electrochemical cell characteristics are deteriorated.

 [0083] The weight ratio of the olefin polymer (A) to the acrylic polymer (B) in the emulsion composition is based on the total weight of the olefin polymer (A) and the acrylic polymer (B). Preferably, (A) is 95 to 30% by weight, (B) is 5 to 70% by weight, more preferably (A) is 95 to 50% by weight, and (B) is 5 to 50% by weight. . When the weight ratio of (A) to (B) is in the above range, it is preferable in terms of electrochemical stability and adhesiveness.

[0084] In the present invention, constituent materials other than the binder used for the electrode for an electrochemical cell are not particularly limited. For example, when the binder of the present invention is used for an electrode for a secondary battery and an electric double layer capacitor, the positive electrode active material and the binder are used for the positive electrode, and the negative electrode active material and the binder are used for the negative electrode. Material strength Other materials such as carbon black, amorphous whisker carbon, graphite, etc. Conductive aids made of these carbon materials may be added.

 [0085] Examples of the negative electrode active material for the secondary battery include metallic lithium, a lithium alloy, a carbon material that can be doubed and dedoped with lithium ions, tin oxide that can be doped and dedoped with lithium ions, Doped with niobium oxide, vanadium oxide, lithium ions' Titanium oxide that can be undope or silicon ions that can be doped or dedoped with lithium ions Transition metal nitrides can be used. Among these, carbon materials that can dope and dedope lithium ions are preferable. Such carbon material may be graphite or amorphous carbon, and carbon black such as activated carbon, carbon fiber, acetylene black, ketjen black, mesocarbon microbeads, natural graphite, etc. are used. It is done.

 [0086] The binder for an electrochemical cell electrode of the present invention may further contain a thickener such as carboxymethyl cellulose and sodium polyacrylate.

 [0087] Examples of positive electrode active materials for secondary batteries include transition metal oxidation such as MoS, TiS, MnO, and V 2 O

 2 2 2 2 5

 And transition metal sulfides; LiCoO, LiMnO, LiMn O, LiNiO, LiNi Co O

 2 2 2 4 2 X (1-X) 2 and other complex oxides composed of lithium and transition metal; conductive materials such as polyaniline, polythiophene, polypyrrole, polyacetylene, polyacene, dimercaptothiadiazole / polyaniline complex A functional polymer material. Among these, a composite oxide composed of lithium and a transition metal is particularly preferable. In the case of negative electrode force S lithium metal or lithium alloy, a carbon material can be used as the positive electrode. In addition, a mixture of a composite oxide of lithium and a transition metal and a carbon material can be used as the positive electrode.

 [0088] Various activated carbons are used as positive and negative electrode active materials for electric double layer capacitors.

[0089] In the present invention, in order to correspond to the usage pattern of the secondary battery, the secondary battery is made of the above-described positive electrode, negative electrode, and separator, which are cylindrical, coin-shaped, rectangular, film-type, etc. It can be manufactured by enclosing a non-aqueous electrolyte in a shape and stacking the above-mentioned positive electrode and negative electrode inside the battery can with the separator as the center.

[0090] In the present invention, the electric double layer capacitor has an arbitrary shape such as a cylindrical shape or a coin shape so as to correspond to the usage in the battery, and the above-described electrode is provided inside the battery can. The electrolyte is encapsulated in a layer that is stacked on both sides of the separator. It can be produced more.

 [0091] The separator used in the secondary battery is a film that electrically insulates the positive electrode and the negative electrode and transmits lithium ions. As the separator, for example, a porous film or a polymer electrolyte is used. A porous polymer film is preferably used as the porous film, and examples of the material of the film include polyolefin, polyimide, polyvinylidene fluoride, and polyester. Among these porous polymer films, in particular, a porous polyolefin film is preferred. Specifically, a porous polyethylene film, a porous polypropylene film, or a multilayer film of a porous polyethylene film and polypropylene is exemplified. be able to. The surface of porous polyolefin film is coated with another resin with excellent thermal stability.

 [0092] As the separator of the electric double layer capacitor, in addition to the separator similar to the secondary battery, a porous film containing electrolytic capacitor paper inorganic ceramic powder can be used.

[0093] Examples of the electrolyte used in the secondary battery include LiPF, LiBF, LiCIO, and LiAsF.

 6 4 4 6

CF SO Li, (CF 2 SO 4) N / Li, and the like. These electrolytes can be used alone or in combination of two or more.

3 3 3 2

 Can be used in combination. These electrolytes are used after being dissolved in an electrolyte such as a non-aqueous electrolyte (organic solvent).

 [0094] Examples of the electrolyte used in the electric double layer capacitor include tetraethyl ammonium tetrafluoroborate and triethyl monomethyl ammonium tetrafluoroborate. These electrolytes can be used alone or in combination of two or more. These electrolytes are used after being dissolved in an electrolytic solution.

 [0095] For the electric double layer capacitor, any electrolytic solution capable of exerting its performance can be used, but a non-aqueous electrolytic solution is preferred as the electrolytic solution.

[0096] Non-aqueous electrolytes used for secondary batteries and electric double layer capacitors include, for example, propylene carbonate, ethylene carbonate, y-butarate rataton, dimethyl sulfoxide, dimethylolene carbonate, ethinolemethinorecarbonate, Examples include organic solvents such as tinole carbonate, 1,2-dimethoxyethane, 1,2-diethoxyethane, and tetrahydrofuran. These non-aqueous electrolytes can be used alone or in combination of two or more. used.

 Example

 Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

[0098] <Preparation of emulsion composition>

 [Example 1]

 Charge 263 parts of ethylene 'methacrylic acid copolymer (Mitsui DuPont Polychemical Co., Ltd. Nyucle Nole N2060, 20 parts of methacrylolic acid) to autoclave and add 2 parts of sodium hydroxide and 712 parts of deionized water at 150 ° C. After stirring for a period of time, the mixture was cooled to obtain an olefin emulsion having a particle size of 20 nm and a nonvolatile content of 27%. 519 parts of this emanolation and 325 parts of deionized water were charged into a reaction vessel, heated to 80 ° C. under a nitrogen stream, and 0.7 part of ammonium persulfate was added. Separately, sodium dodecylbenzenesulfonate in 32 parts of 2-ethylhexylaretalate 32 parts, 63 parts of styrene, 42 parts of hydroxymethytalate and 3 parts of ethylene glycol dimetatalate in 56 parts of deionized water 0 An emulsified mixture emulsified with 3 parts was prepared, and this emulsified mixture was dropped into the reaction vessel in 3 hours, and then kept at the same temperature for 2 hours to complete the polymerization. The obtained emulsion had a nonvolatile content of 27%, a pH of 9.5, and a weight average particle size of 60 nm as measured by light scattering.

[0099] [Example 2]

 735 parts of olefin fin emulsion obtained in Example 1 and 198 parts of deionized water were charged into a reaction vessel, heated to 80 ° C. under a nitrogen stream, and 0.4 part of ammonium persulfate was added. Separately, 19.4 parts of 2-ethylhexyl acrylate, 38.3 parts of styrene, 25.5 parts of hydroxyethyl methacrylate, 1.8 parts of ethylene glycol dimethacrylate are added in 34 parts of deionized water. An emulsified mixture emulsified using a part was prepared, and this emulsified mixture was dropped into the reaction vessel in 2 hours, and then kept at the same temperature for 2 hours to complete the polymerization. The obtained emulsion had a nonvolatile content of 27%, a pH of 9.5, and a weight average particle size of 60 nm as measured by light scattering.

[0100] [Example 3]

519 parts of olefin fin emulsion obtained in Example 1 and 325 parts of deionized water in a reaction vessel. The mixture was charged and heated to 80 ° C under a nitrogen stream, and 0.7 parts of ammonium persulfate was added. Separately, emulsification of 49 parts of 2-ethylhexyl acrylate, 90 parts of methyl metatalylate and 1 part of divinylbenzene in 56 parts of deionized water using 0.3 part of sodium dodecylbenzenesulfonate. A mixture was prepared, and this emulsified mixture was added dropwise to the reaction vessel in 3 hours. Thereafter, the mixture was further maintained at the same temperature for 2 hours to complete the polymerization. The obtained emulsion had a nonvolatile content of 27%, a pH of 9.5, and a weight average particle size of 120 nm as measured by light scattering.

[0101] [Example 4]

 519 parts of olefin fin emulsion obtained in Example 1 and 325 parts of deionized water were charged into a reaction vessel, heated to 80 ° C. under a nitrogen stream, and 0.7 part of ammonium persulfate was added. In addition to this IJ, 49 parts of 2-ethylhexyl acrylate, 81 parts of styrene, 7 parts of methacrylic acid, 3 parts of daricidylmethalate 3 parts of sodium dodecylbenzenesulfonate in 56 parts of deionized water An emulsified mixture emulsified using was prepared, and this emulsified mixture was dropped into the reaction vessel in 3 hours, and then kept at the same temperature for 2 hours to complete the polymerization. The obtained emulsion has a non-volatile content of 27%, a pH of 9.5, and a weight average particle diameter of 60 nm as measured by light scattering.

 [0102] [Example 5]

 A reaction vessel was charged with 83 parts of deionized water and 0.2 part of sodium dodecinolebenzenesulfonate, and the temperature was raised to 80 ° C under a nitrogen stream. After raising the temperature, 0.5 part of potassium persulfate was poured into the reaction vessel. Separately, 3 parts of methacrylic acid, 10 parts of Epomic R140 (Mitsui Chemicals, diglycidyl ether compound), 47 parts of styrene, 2 parts —Ethylhexyl acrylate: 40 parts of deionized water and 0.4 parts of sodium dodecylbenzenesulfonate were used to make an emulsified mixture, and this emulsified mixture was dropped into the reaction vessel over 4 hours. Thereafter, the polymerization was completed by further maintaining at the same temperature for 3 hours. This polymerization solution having acrylic emulsion strength was adjusted to pH 8 with 5% sodium hydroxide. The resulting acrylic emulsion had a non-volatile content of 40% and a weight average particle diameter of lOOnm as measured by light scattering.

[0103] 30 parts of acrylic emulsion prepared as described above in terms of non-volatile content and 70 parts of olefin fin emulsion prepared in Example 1 in terms of non-volatile content were added and stirred, then distilled water was added and solid content was added. A 25% emulsion composition was prepared. [Example 6]

 Chemipearl S650 (ethylene monounsaturated carboxylic acid copolymer, neutralized sodium hydroxide, non-volatile content 27% by weight, manufactured by Mitsui Chemicals, Inc.) 346 parts by weight in a reaction vessel under nitrogen flow And 93 parts by weight of deionized water were charged, and the temperature of the reactor was raised to 80 ° C. To the reactor at 80 ° C, 0.2 parts by weight of ammonium persulfate was further added. Separately, 16 parts by weight of deionized water, 16 parts by weight of 2-ethylhexyl acrylate, 10 parts by weight of hydroxyethyl methacrylate, 11 parts by weight of styrene, 3 parts by weight of divinylbenzene, and emulsifier An emulsion mixture was prepared by adding 0.2 parts by weight of sodium dodecylbenzenesulfonate. This emulsified mixture was dropped into the reaction vessel maintained at 80 ° C. for 3 hours, and then further reacted at the same temperature for 2 hours to complete the polymerization. The obtained emulsion composition had a nonvolatile content of 27% by weight and a pH of 9.5, and the weight average particle diameter measured by light scattering was lOOnm.

[0105] [Example 7]

 70 parts by weight of Chemipearl S650, a polyolefin emulsion, was added to 30 parts by weight of acrylic emulsion prepared in Example 5 and stirred, and distilled water was further added to prepare an emulsion composition having a solid content of 25% by weight. did.

[Comparative Example 1]

 519 parts of olefin fin emulsion prepared in Example 1 and 325 parts of deionized water were charged into a reaction vessel, heated to 80 ° C. under a nitrogen stream, and 0.7 part of ammonium persulfate was added. Separately, emulsify 32 parts of 2-ethinohexenorea talelate, 63 parts of styrene, and 42 parts of hydroxyethynole methacrylate with 0.3 part of sodium dodecylbenzenesulfonate in 56 parts of deionized water. An emulsion mixture was prepared, and this emulsion mixture was added dropwise to the reaction vessel in 3 hours, and then kept at the same temperature for 2 hours to complete the polymerization. The obtained emulsion had a non-volatile content of 27%, a pH of 9.5, and a weight average particle size of 60 nm as measured by light scattering.

[Comparative Example 2]

A reaction vessel was charged with 83 parts of deionized water and 0.2 part of sodium dodecinolebenzenesulfonate, and the temperature was raised to 80 ° C under a nitrogen stream. After the temperature rise, throw 0.5 parts of potassium persulfate into the reaction vessel. Separately, Epocomic R140 (Mitsui Chemicals Co., Ltd., diglycidinoreetherified product) 10 parts, styrene 50 parts, 2-ethyl hexyl acrylate is 40 parts deionized water in deionized water 40 parts An emulsified mixture was prepared by using 0.4 part of soda, and this emulsified mixture was dropped into the reaction vessel in 4 hours, and then kept at the same temperature for 3 hours to complete the polymerization. A polymerization solution comprising this acrylic emulsion was adjusted to pH 8 with 5% sodium hydroxide. The non-volatile content of the resulting acrylic emulsion is 45. / ₀ , The weight average particle diameter measured by light scattering was lOOnm.

 [0108] 30 parts of acrylic emulsion prepared as described above in terms of non-volatile content and 70 parts of olefin fin emulsion prepared in Example 1 in terms of non-volatile content were added and stirred, and then distilled water was added and solid content was added. A 25% emulsion composition was prepared.

 [0109] <Production of secondary battery negative electrode>

 [Example A]

 Natural graphite (LF18A manufactured by Chuetsu Graphite Co., Ltd.) Thickener carboxymethylcellulose solution (Daicel Chemical Co., Ltd. CMC Daicel 1160) adjusted to 1.2% by weight with 97 parts by weight is converted to solid content 1 After mixing parts by weight, the emulsion composition prepared in Example 1 was mixed with 2 parts by weight in terms of solid content, and distilled water was further added to prepare a negative electrode mixture slurry having a solid content concentration of 50% by weight. Next, this negative electrode mixture slurry was applied to a negative electrode current collector made of a strip-shaped copper foil having a thickness of 18 / m, and then dried and compression molded to produce a negative electrode having a thickness of 70 / m.

[0110] [Example B]

 A negative electrode having a thickness of 70 μm was produced in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Example 2.

[0111] [Example C]

 A negative electrode having a thickness of 70 μm was prepared in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Example 3.

[0112] [Example D]

A negative electrode having a thickness of 70 μm was prepared in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Example 4. [0113] [Example]

 A negative electrode having a thickness of 70 μm was prepared in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Example 5.

[0114] [Example F]

 A negative electrode having a thickness of 70 μm was prepared in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Example 6.

[0115] [Example G]

 A negative electrode having a thickness of 70 μm was prepared in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Example 7.

[0116] [Comparative Example A]

 A negative electrode having a thickness of 70 μm was prepared in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Comparative Example 1.

[0117] [Comparative Example B]

 A negative electrode having a thickness of 70 μm was prepared in the same manner as in Example A except that the emulsion composition was changed to the emulsion prepared in Comparative Example 2.

[0118] [Comparative Example C]

 NMP (N-methyl-2-pyrrolidone) solution of natural graphite (LF18A made by Chuetsu Graphite Co., Ltd.) 98 parts by weight and non-volatile content 8% by weight (polyvinylidene fluoride) (Kureha Chemical Industry Co., Ltd.) KF Polymer # 1120) 25 parts by weight was added, and NMP for viscosity adjustment was further mixed to prepare a negative electrode mixture slurry. Next, this negative electrode mixture slurry was applied to a negative electrode current collector made of a strip-shaped copper foil having a thickness of 18 μ 、 η, and then dried and compression molded to produce a negative electrode having a thickness of 70 / m.

[0119] [Comparative Example D]

 A negative electrode having a thickness of 70 zm was prepared in the same manner as in Example A except that the emulsion composition was changed to an aqueous dispersion of SBR having a nonvolatile content of 48% by weight (SR143 manufactured by Nippon A & L Co., Ltd.).

[0120] <Preparation of positive electrode for secondary battery>

[Example H] LiCoO (Honsho FMC Energy Systems Co., Ltd. HLC—22) 85 · 5 parts by weight, graphite 8 parts by weight, acetylene black 3 parts by weight and carboxymethylcellulose (Daicel Chemical Co., Ltd. 1160) 1.5 parts by weight in terms of solid content Then, 2 parts of the emulsion composition prepared in Example 1 in terms of solid content was added to prepare a LiCoO mixture slurry. This LiCoO mixture slurry was applied to an aluminum foil with a thickness of 20 μm, dried and compression molded to produce a positive electrode with a thickness of 70 am.

[0121] [Example I]

 A positive electrode having a thickness of 70 μm was produced in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Example 2.

[0122] [Example J]

 A positive electrode having a thickness of 70 μm was prepared in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Example 3.

[0123] [Example K]

 A positive electrode having a thickness of 70 μm was produced in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Example 4.

[0124] [Example]

 A positive electrode having a thickness of 70 μm was produced in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Example 5.

[0125] [Example M]

 A positive electrode having a thickness of 70 μm was produced in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Example 6.

[0126] [Example N]

 A positive electrode having a thickness of 70 μm was produced in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Example 7.

[0127] [Comparative Example E]

 A positive electrode having a thickness of 70 μm was prepared in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Comparative Example 1.

[0128] [Comparative Example F] A positive electrode having a thickness of 70 μm was prepared in the same manner as in Example H except that the emulsion composition was changed to the emulsion prepared in Comparative Example 2.

[Comparative Example G]

 LiCoO (Honjo FMC Energy Systems Co., Ltd. HLC_22) 87 parts by weight, 8 parts by weight of graphite, 3 parts by weight of acetylene black and 8% by weight of non-volatile PVDF NMP solution (KF Polymer, Kureha Chemical Industry Co., Ltd.) # 1120) After mixing 25 parts by weight, NMP for viscosity adjustment was further mixed to prepare a LiCoO mixture slurry. This LiCoO mixture slurry was applied to an aluminum foil having a thickness of 20 am, and then dried and compression molded to produce a positive electrode having a thickness of 70 am.

 [0130] <Evaluation of adhesion of secondary battery>

 The electrodes prepared in Examples A to G and Comparative Examples A to G were cut and attached to a glass preparation with an instantaneous adhesive to fix the electrodes to obtain samples for evaluation. The sample for evaluation was cut with the coating film peel strength measuring device Cycus DN20 (Daibrowintes Co., Ltd.) at the horizontal speed of 2 μm / sec. The peel strength between the composite layer and the current collector interface was measured from the horizontal force. Adhesiveness was evaluated by taking an average value of peel strength three times. The results are shown in Table 1.

[0131] [Table 1]

【table 1】

[0132] <Preparation of non-aqueous electrolyte for secondary battery>

 As a non-aqueous solvent, a mixture of ethylene carbonate (EC) and ethylmethyl carbonate (EMC) in a ratio of EC: MEC = 4: 6 (weight ratio) is used, and then the electrolyte LiPF

 A non-aqueous electrolyte was prepared so that 6 was dissolved and the electrolyte concentration was 1.0 mol Z liter.

 [0133] <Production of coin-type secondary battery>

 The negative electrode made in Examples A, B, D, C, E, and Comparative Examples A and B as a negative electrode for a coin-type battery was punched into a disk shape with a diameter of 14 mm, and a coin-shaped negative electrode with a weight of 20 mg / l4 mm ci) was formed. Obtained.

[0134] The positive electrode produced in Examples F, G, H, I, J, and Comparative Examples C and D as a positive electrode for a coin-type battery was punched out into a disk shape having a diameter of 13.5 mm, and the weight was 42 mg / l 3.5 mm φ. A coin-shaped positive electrode was obtained. The above-mentioned coin-shaped negative electrode, positive electrode, and separator made of porous polypropylene film with a thickness of 25 / im and a diameter of 16 mm are placed in the negative electrode can of a stainless steel 2032 size battery can. Laminated in order. Thereafter, 0.04 ml of the non-aqueous electrolyte was poured into the separator, and an aluminum plate (thickness 1.2 mm, diameter 16 mm) and a spring were stacked on the laminate. Finally, through a polypropylene gasket Then, cover the positive electrode can of the battery and force the can lid to maintain the airtightness in the battery.

A coin-type battery having a diameter of 20 mm and a height of 3.2 mm was produced.

 [0135] <Evaluation of battery cycle characteristics>

 Using the coin battery made as described above, charge this battery under the condition of 0.5mA constant current and 4.2V constant voltage until the current value at 4.2V constant voltage becomes 0.05mA. After that, discharging was performed under the condition of 1 mA constant current 3.0 V constant voltage until the current value at 3.0 V constant voltage became 0.05 mA. This cycle was repeated 200 times, and the capacity% after 200 cycles with respect to the initial battery capacity was evaluated. Table 2 shows the evaluation results of the battery using each electrode.

[0136] [Table 2]

[Table 2]

<Production of electric double layer capacitor electrode>

 [Example 0]

Activated carbon (Kuraray RP-20) 100 parts by weight, acetylene black (Electrochemical Co., Ltd. Denka Black) 3 parts by weight, Ketjen Black (Ketjen Black International Co., Ltd. EC600JD) 1.2 parts by weight Mix 1.5 parts by weight of the adjusted thickener carboxymethyl cellulose (Daicel Chemical Co., Ltd. CMC1160) in terms of solid content. In addition, 5 parts of the emulsion composition prepared in Example 1 was mixed in terms of solid content, and distilled water was further added to prepare a mixture slurry having a solid content concentration of 50% by weight. Next, this negative electrode mixture slurry was applied to a current collector made of a strip-shaped aluminum foil having a thickness of 20 μΐη, dried, and compression molded to produce a 70 μm thick electrode.

[0138] [Example P]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Example 2.

[0139] [Example Q]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Example 3.

[0140] [Example R]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Example 4.

[0141] [Example S]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Example 5.

[0142] [Example T]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Example 6.

[Example U]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Example 7.

[0144] [Comparative Example H]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Comparative Example 1.

[0145] [Comparative Example I]

An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to the emulsion prepared in Comparative Example 2. [0146] [Comparative Example J]

 An electrode having a thickness of 70 μm was prepared in the same manner as in Example O except that the emulsion composition was changed to a PTFE aqueous dispersion (Daikin Kogyo D-2C).

[0147] <Evaluation of electric double layer capacitor adhesion>

 Examples 0 to T Comparative Examples The electrodes prepared in H to J were evaluated in the same manner as in the evaluation of secondary battery adhesion. The results are shown in Table 3.

[0148] [Table 3]

[Table 3]

[0149] <Preparation of electrolytic solution of electric double layer capacitor>

 An electrolyte was prepared by dissolving tetraethylammonium tetrafluoroborate, an electrolyte, in propylene carbonate, so that the electrolyte concentration was 1.5 mol / liter.

 [0150] <Production of coin-type electric double layer capacitor>

Examples 0 to U Comparative Examples The electrodes prepared in H to J were punched into a disk shape having a diameter of 14 mm to obtain a coin-shaped electrode having a weight of 20 mg / 14 mmφ. [0151] A separator made of the above-mentioned coin-shaped electrode and a porous polypropylene film having a thickness of 25 μm and a diameter of 16 mm was placed in a negative electrode can of a stainless steel 2032 size battery can. Laminated in order. Thereafter, 0.04 ml of the electrolyte solution was injected into the separator, and then an aluminum plate (thickness 1.2 mm, diameter 16 mm) and a spring were stacked on the laminate. Finally, the battery can is covered with a polypropylene gasket, and the can lid is caulked to maintain the airtightness of the battery, producing a coin-type battery with a diameter of 20 mm and a height of 3.2 mm. did.

 [0152] <Evaluation of characteristics of electric double layer capacitor>

 Using the coin-type electric double layer capacitor fabricated as described above, the battery was charged at a constant current of 10 mA to 2.7 V for 10 minutes and then discharged at a constant current of 1 mA. The capacitance was determined from the obtained charge / discharge characteristics. The internal resistance was calculated according to the calculation method of standard RC-2377 established by the Japan Electronics and Information Technology Industries Association based on the charge / discharge characteristics. Table 4 shows the evaluation results for capacitors using each electrode.

 [0153] [Table 4]

[Table 4]

 Electrode Composition Electrostatic capacity (F / g) Internal resistance (Q F)

 Example o Example 1 45 4.0

 Example P Example 2 44 4.0

 Example Q Example 3 45 3.9

 Example R Example 4 44 4.0

 Example S Example 5 45 4.0

 Example T Example 6 45 4.0

 Example u Example 7 44 4.0

 Comparative Example H Comparative Example 1 32 4.4

 Comparative Example I Comparative Example 2 30 4.6

 Comparative Example J Comparative Example 3 32 4.4

Claims

The scope of the claims  [1] A binder for an electrochemical cell electrode comprising an emulsion composition in which resin particles formed from an olefin polymer (A) and an acrylic polymer (B) having an internally crosslinked structure are dispersed in water.  [2] An acrylic polymer (B) having an internal crosslinking structure is produced from a monomer containing an acrylic monofunctional monomer (b-1) and a polyfunctional monomer (b-2). The binder for an electrochemical cell electrode according to claim 1, wherein:  [3] Acrylic polymer (B) having an internal cross-linked structure is composed of an acrylic monofunctional monomer (b— 1 2) having a reactive group, and the acrylic monomer (b— 1 2 2. The binder for an electrochemical cell electrode according to claim 1, wherein the binder for an electrochemical cell electrode is produced from a compound containing the compound (c) having two or more groups capable of reacting with the reactive group (1).  [4] The acrylic monomer of the compound (c) wherein the reactive group of the acrylic monofunctional monomer (b-12) having the reactive group is a carboxyl group and / or a hydroxyl group 4. The binder for electrochemical cell electrodes according to claim 3, wherein the group that reacts with the reactive group of (b-12) is an epoxy group.  [5] An acrylic polymer (B) having an internal cross-linked structure reacts with an acrylic monofunctional monomer (b-1 1 2) having a reactive group (1) and a reactive group (1). The binder for an electrochemical cell electrode according to claim 1, wherein the binder for an electrochemical cell electrode is produced from a monomer containing an acryl-based monofunctional monomer having a reactive group (2). [6] The binder for an electrochemical cell electrode according to any one of [5] to [5], wherein the olefin polymer (A) contains a copolymer of an olefin monomer (a_l). . [7] The olefin polymer (A) comprises a copolymer of an olefin monomer (a_l) and another monomer (a-2) copolymerizable with the olefin monomer. :! ~ 6, Electrochemical cell electrode binder according to any of the above. [8] Olefin monomers (a— 1) and other monomers copolymerizable with olefin monomers (a— The ratio of 2) is 99. Based on the total weight of (a-1) and (a-2). The binder for an electrochemical cell electrode according to claim 7, wherein the binder is 9 to 35.0% by weight and (a-2) is 0.1 to 65.0% by weight. [9] Based on the total weight of the olefin polymer (A) and the acrylic polymer (B) in emulsion, the olefin polymer (A) is 95 to 30% by weight, and the acrylic polymer (B). The binder for an electrochemical cell electrode according to any one of claims 1 to 8, wherein the binder is 5 to 70% by weight.  [10] An electrode comprising the binder according to any one of claims 1 to 9. [11] An electrochemical cell using the electrode according to claim 10 as a positive electrode and / or a negative electrode. 12. The electrochemical cell according to claim 11, wherein the electrochemical cell is a secondary battery. 13. The electrochemical sensor according to claim 11, wherein the electrochemical cell is an electric double layer capacitor.