JPWO2019155980A1 - Slurry for non-aqueous battery electrodes, and method for manufacturing non-aqueous battery electrodes and non-aqueous batteries - Google Patents

Abstract

Provided is a slurry for a non-aqueous battery electrode capable of obtaining an electrode in which cracks are unlikely to occur even if the slurry is thickly coated to form a thick electrode active material layer. The slurry for non-aqueous battery electrodes of the present invention contains the active material (A) for non-aqueous battery electrodes, the binder resin (B), the crack inhibitor (C), and water, and the crack inhibitor (C). ) Shall have a boiling point of 120 ° C. or higher at 1 atm and a solubility in water at 20 ° C. of 10 g / 100 mL or higher.

Description

The present invention relates to a slurry for non-aqueous battery electrodes, and a method for producing non-aqueous battery electrodes and non-aqueous batteries.
The present application claims priority based on Japanese Patent Application No. 2018-022334 filed in Japan on February 9, 2018, the contents of which are incorporated herein by reference.

In recent years, lithium-ion non-aqueous batteries have been attracting attention from the viewpoints of miniaturization and weight reduction of electronic devices such as notebook computers, communication devices such as mobile phones, and power tools.

The lithium ion non-aqueous battery includes a positive electrode using a metal oxide such as lithium cobalt oxide as an active material, a negative electrode using a carbon material such as graphite as an active material, and an electrolytic solution solvent mainly containing carbonates. In a lithium ion non-aqueous battery, the battery is charged and discharged by moving lithium ions between the positive electrode and the negative electrode.
The positive electrode can be obtained by forming a positive electrode layer from a composition containing a positive electrode active material such as a metal oxide and a binder on the surface of a positive electrode current collector such as aluminum foil. The negative electrode is obtained by forming a negative electrode layer from a composition containing a negative electrode active material such as graphite and a binder on the surface of a negative electrode current collector such as copper foil. Therefore, each binder has a role of binding the active material and the binder and preventing cohesive failure of the positive electrode layer and the negative electrode layer.

As a binder, a polyvinylidene fluoride (PVDF) -based binder using an organic solvent-based N-methylpyrrolidin-2-one (NMP) as a solvent is well known (see, for example, Patent Document 1). However, this binder has a drawback that the binding property between the active materials and the active material and the current collector is low, a large amount of binder is required for actual use, and as a result, the capacity of the non-aqueous battery is reduced. Further, since NMP, which is an expensive organic solvent, is used as the binder, there are problems in the price of the final product and the preservation of the working environment when producing the slurry or the current collector.

As a method for solving these problems, the development of an aqueous dispersion binder has been promoted. For example, a styrene-butadiene rubber (SBR) -based aqueous dispersion using carboxymethyl cellulose (CMC) as a thickener is known (see, for example, Patent Documents 2 to 4). Further, as an aqueous dispersion type binder used for an electrode of a secondary battery, Patent Document 5 describes styrene, an ethylenically unsaturated carboxylic acid ester monomer, an ethylenically unsaturated carboxylic acid monomer, and an internal cross-linking. It has been proposed that an ethylenically unsaturated monomer containing an agent is emulsion-polymerized in the presence of a surfactant.
Since these are aqueous dispersions, they are inexpensive and are advantageous from the viewpoint of preserving the working environment. In addition, since the binding properties between the active materials and the active material and the current collector are relatively good, it is possible to produce electrodes with a smaller amount of use than PVDF binders, and as a result, the output of non-aqueous batteries is high. There is an advantage that the capacity can be increased and the capacity can be increased.

Recently, from the viewpoint of environmental friendliness, lithium ion non-aqueous batteries having high voltage, high capacity, and high energy density have been strongly demanded as non-aqueous batteries for electric vehicles or hybrid vehicles.
As a measure for improving these, there is a method of thickly coating the electrode current collector with a slurry to form a thick electrode active material layer.
However, when the thick coating is applied, the electrodes are liable to crack, and the battery performance is not always good.

Japanese Unexamined Patent Publication No. 10-298386 Japanese Unexamined Patent Publication No. 5-74461 Japanese Unexamined Patent Publication No. 8-250123 Japanese Unexamined Patent Publication No. 2011-204573 Japanese Unexamined Patent Publication No. 2011-243464

The present invention solves the problems of the prior art, is an aqueous dispersion system, has good binding properties between active materials and between active materials and a current collector, and is less likely to crack even when thickly applied. An object of the present invention is to provide a slurry for a non-aqueous battery electrode in which an active material is not easily peeled off from the surface of a current collector, and a method for producing a non-aqueous battery electrode and a non-aqueous battery using the slurry.

The present inventors have studied diligently to solve the above problems, and have focused on the fact that cracks can be prevented by adding a specific organic solvent as a crack inhibitor to the aqueous dispersion slurry, and have solved the above problems. It came to a solution.
That is, the present invention includes the following aspects.

[1] A slurry for non-aqueous battery electrodes containing an active material (A) for non-aqueous battery electrodes, a binder resin (B), a crack inhibitor (C), and water.
The crack inhibitor (C) is a slurry for non-aqueous battery electrodes having a boiling point of 120 ° C. or higher at 1 atm and a solubility in water at 20 ° C. of 10 g / 100 mL or higher.
[2] The crack inhibitor (C) is N-methylpyrrolidin-2-one, ethylene glycol, diethylene glycol, ethylene glycol monobutyl ether, 3-methoxy-3-methyl-1-butanol, N, N-dimethylformamide, dimethyl. The slurry for non-aqueous battery electrodes according to [1], which is at least one selected from sulfoxide.
[3] The slurry for non-aqueous battery electrodes according to [1], wherein the crack inhibitor (C) is an organic solvent having a boiling point of 150 ° C. or higher at 1 atm.
[4] The slurry for non-aqueous battery electrodes according to claim 1, wherein the crack inhibitor (C) is an organic solvent having a boiling point of more than 200 ° C. at 1 atm.
[5] The slurry for a non-aqueous battery electrode according to any one of [1] to [4], which contains 10 to 500 parts by mass of the crack inhibitor (C) with respect to 100 parts by mass of the binder resin (B).
[6] The slurry for a non-aqueous battery electrode according to any one of [1] to [5], which further contains a thickener (D).
[7] The slurry for non-aqueous battery electrodes according to [6], wherein the thickener (D) is carboxymethyl cellulose (CMC).
[8] The binder resin (B) is a copolymer of a styrene-based monomer and a diene-based monomer, and a copolymer of a styrene-based monomer and an ethylenically unsaturated carboxylic acid ester monomer. The slurry for a non-aqueous battery electrode according to any one of [1] to [7], which is at least one selected from.
[9] The binder resin (B) contains a copolymer of a styrene-based monomer and a diene-based monomer, and is styrene-based among all ethylenically unsaturated monomer components constituting the copolymer. The slurry for a non-aqueous battery electrode according to any one of [1] to [8], wherein the monomer component is 5 to 70% by mass and the diene-based monomer component is 30 to 95% by mass.
[10] The non-aqueous system according to any one of [1] to [9], wherein the binder resin (B) contains a copolymer of a styrene-based monomer and an ethylenically unsaturated carboxylic acid ester monomer. Styrene for battery electrodes.
[11] The binder resin (B) contains a copolymer of a styrene-based monomer, an ethylenically unsaturated carboxylic acid ester monomer, and an ethylenically unsaturated carboxylic acid monomer [1] to [1]. 10] The slurry for a non-aqueous battery electrode according to any one of.
[12] The amount of styrene used in the binder resin (B) is 10 to 70% by mass of the total ethylenically unsaturated monomer component forming the copolymer.
The amount of the ethylenically unsaturated carboxylic acid ester monomer used is 25 to 85% by mass of the total ethylenically unsaturated monomer component forming the copolymer.
The non-aqueous battery according to [11], wherein the amount of the ethylenically unsaturated carboxylic acid monomer used is 0.01 to 10% by mass of the total ethylenically unsaturated monomer component forming the copolymer. Slurry for electrodes.
[13] A method for producing a non-aqueous battery electrode, which comprises a step of applying the slurry according to any one of [1] to [12] on a current collector and curing the slurry.
[14] A method for manufacturing a non-aqueous battery, which comprises the process for manufacturing the non-aqueous battery electrode according to [13].

By using the slurry for non-aqueous battery electrodes of the present invention, it is possible to obtain an electrode that is less likely to crack even if the slurry is thickly coated to form a thick electrode active material layer.

(Slurry for non-aqueous battery electrodes)
The slurry for non-aqueous battery electrodes of the present invention contains an active material (A), a binder resin (B), a crack inhibitor (C), and water as essential components. The crack inhibitor (C) is characterized by having a boiling point of 120 ° C. or higher at 1 atm and a solubility in water at 20 ° C. of 10 g / 100 mL or higher. Further, (D) thickener may be further contained.
In the present specification, "(meth) acrylic" is a general term for acrylic and methacrylic, and "(meth) acrylate" is a general term for acrylate and methacrylate.

[Active material (A)]
The slurry for non-aqueous battery electrodes of the present invention contains the active material (A) as an essential component. The active material used in the present invention may be either a positive electrode active material or a negative electrode active material. In the non-aqueous battery electrode slurry of the embodiment of the present invention, the active material (A) is the negative electrode active material. When a negative electrode active material is used as the active material (A), the effect is likely to be exhibited.
The shape of the active material is not particularly limited, and a spherical or flaky material can be used. The average particle size of the active material (50% median diameter on a volume basis) is preferably 5 to 100 μm, more preferably 10 to 50 μm, and 15 to 30 μm from the viewpoint of dispersibility of the active material. It is more preferable to have. The 50% median diameter on a volume basis can be calculated by a laser diffraction method.
BET specific surface area of the active material, from the viewpoint of the dispersibility of the active material is preferably 0.1 to 100 m ² / g, more preferably 0.5~50m ² / g, 1.0~ It is more preferably 30 m ² / g. The BET specific surface area can be obtained from the specific surface area measurement by the BET nitrogen adsorption method (according to JIS Z8830).

Examples of the positive electrode active material include metal composite oxides containing at least one kind of metal such as lithium and iron, cobalt, nickel and manganese. Preferably, Li _{x My1} O ₂ (where M represents at least one of one or more transition metals, preferably Co, Mn or Ni, with 1.10>x> 0.05, 1 ≧ y1> 0. Yes), Li _{x My2} O ₄ (where M represents one or more transition metals, preferably Mn or Ni, 1.10>x> 0.05, 2 ≧ y2> 0), or Li _{x My1} PO ₄ (where M represents at least one of one or more transition metals, preferably Fe, Co, Mn or Ni, 1.10>x> 0.05, 1 ≧ y1> 0. ) Etc. can be mentioned. Specific _{examples, LiCoO 2, LiNiO 2, Li} x Ni y3 Mn z Co a O 2 ( wherein, 1.10>x>0.05,1> y3 >0,1>z>0,1> a > 0), LiMn ₂ O ₄ , LiFePO _{4, and} other composite oxides.

The negative electrode active material is not particularly limited as long as it can store and release metal ions (for example, lithium ions) electrochemically. Specific examples include carbonaceous substances, metal composite oxides, silicon compounds and the like.
As the carbonaceous substance, for example, graphites such as artificial graphite and natural graphite; coke such as petroleum coke, pitch coke, and coal coke can be used. As the metal composite oxide, for example, lithium titanate or the like can be used. As the silicon compound, silicon, silicon oxide and the like can be used. An extremely remarkable effect can be exhibited when these active materials are used.
Among these active materials, carbonaceous substances, particularly graphites or cokes among the carbonaceous substances, are preferable from the viewpoint of improving the binding property. Among them, from the viewpoint of energy density per volume, it is more preferable to use graphites such as artificial graphite and natural graphite. Further, among active materials other than carbonaceous substances, lithium titanate such as Li ₄ Ti ₅ O ₁₂ and silicon, silicon and the like are also suitable from the viewpoint of energy density per volume.
One of these active substances may be used alone, or two or more thereof may be used in combination.
The content ratio of the active material in the non-volatile component in the slurry of the present invention is preferably 90.0 to 99.5% by mass, more preferably 95.0 to 99.0% by mass, and 96.0. It is more preferably ~ 98.0% by mass. The non-volatile component of the slurry is a component that remains after the slurry is dried in the air at 105 ° C. for 1 hour. The "nonvolatile content of the slurry" is the ratio of the non-volatile components contained in the slurry.

[Binder resin (B)]
The slurry for non-aqueous battery electrodes of the present invention contains the binder resin (B) as an essential component.
The content ratio of the binder resin (B) in the non-volatile component in the slurry of the present invention is preferably 0.5 to 5.0% by mass, more preferably 0.5 to 2.0% by mass. It is more preferably 0.5 to 1.8% by mass.
The binder resin (B) used in the present invention is not particularly limited as long as the active material (A) can be uniformly dispersed, but may be a polymer of one or more kinds of ethylenically unsaturated monomers. preferable.

The binder resin (B) used in the present invention preferably has a glass transition temperature of 30 ° C. or lower, more preferably 20 ° C. or lower, from the viewpoint of making the electrodes formed from the slurry of the present invention less likely to crack. It is more preferable to keep the temperature below ° C. From the viewpoint of handleability, the glass transition temperature of the binder resin (B) is preferably −20 ° C. or higher.

The glass transition temperature of the binder resin (B), the ethylenically unsaturated monomers used in the polymerization of the binder resin _{(B) M i (i =} 1,2, ..., i) a glass of each homopolymer transition temperature _{Tg i (i = 1,2, ...} , i) and, each weight fraction of ethylenically unsaturated monomers _{M i X i (i = 1,2} , ..., i) from the , Can be calculated as a theoretical value by the following formula (I).

1 / Tg = Σ (X _i / Tg _i ) ‥ (I)

It is more preferable that the binder resin (B) is dispersed in an aqueous emulsion (EM) using water as a dispersion medium as a raw material for the slurry.

The aqueous emulsion (EM) of the binder resin (B) can be prepared by the following method.
(1) An aqueous emulsion (EM) is prepared by dispersing the binder resin (B) in water using an emulsifier and a homogenizer.
(2) An aqueous emulsion (EM) is prepared by emulsion polymerization using a polymerizable monomer and an emulsifier that produce a binder resin (B).
The binder resin (B) preferably has an acid value of 100 mgKOH / g or less, more preferably 75 mgKOH / g or less, and even more preferably 50 mgKOH / g or less.
The content of the binder resin (B) in the water-based emulsion (EM), that is, the non-volatile content of the water-based emulsion (EM) is preferably 1 to 60% by mass, more preferably 1 to 55% by mass.

The binder resin (B) used in the present invention is, for example, a copolymer (P1) of a styrene-based monomer such as styrene-butadiene rubber and a diene-based monomer; a styrene-based monomer and ethylenically unsaturated. Copolymer with carboxylic acid ester monomer (P2); Ethylene-ethylene unsaturated carboxylic acid such as ethylene-vinyl acetate copolymer, ethylene-vinyl versaticate copolymer, ethylene-acrylic acid ester copolymer, etc. Examples thereof include ester copolymers. Among these, the copolymer of the styrene-based monomer and the diene-based monomer (P1) and the copolymer of the styrene-based monomer and the ethylenically unsaturated carboxylic acid ester monomer (P2) are It is preferable in that the binding property between the active material and the binder resin (B) can be improved, the swelling resistance to the electrolyte solvent is excellent, and the charge / discharge cycle characteristics are excellent. Further, the copolymer (P1) of the styrene-based monomer and the diene-based monomer and the copolymer (P2) of the styrene-based monomer and the ethylenically unsaturated carboxylic acid ester monomer are collected. It is good in that it is also excellent in binding to an electric body.

<Copolymer of styrene-based monomer and diene-based monomer (P1)>
The copolymer (P1) of the styrene-based monomer and the diene-based monomer (hereinafter, may be simply referred to as "copolymer (P1)") is styrene, chlorostyrene, vinyltoluene, t-. Structural units derived from styrene-based monomers such as butyl styrene, vinyl benzoic acid, methyl vinyl benzoate, vinyl naphthalene, chloromethyl styrene, hydroxymethyl styrene, α-methyl styrene; and diene-based monomers such as butadiene and isoprene. It is a copolymer having a structural unit derived from the body.
A copolymer of a styrene-based monomer and a diene-based monomer can be obtained, for example, by emulsion-polymerizing a raw material composition containing styrene and butadiene in an aqueous solvent in the presence of an emulsifier.

In the copolymer (P1) of the styrene-based monomer and the diene-based monomer, the ratio of the structural unit derived from the diene-based monomer is preferably 30 to 95% by mass, more preferably 40 to 90% by mass. , More preferably 50 to 70% by mass. That is, the ratio of the diene-based monomer contained in the raw material for producing the copolymer (P1) of the styrene-based monomer and the diene-based monomer is preferably 30 to 95% by mass or more, more preferably 30 to 95% by mass or more. It is 40 to 90% by mass, more preferably 50 to 70% by mass.
The ratio of the structural unit derived from the styrene-based monomer in the copolymer (P1) of the styrene-based monomer and the diene-based monomer is preferably 5 to 70% by mass, more preferably 10 to 60% by mass. .. That is, the ratio of the styrene-based monomer contained in the raw material for producing the copolymer (P1) of the styrene-based monomer and the diene-based monomer is preferably 5 to 70% by mass, preferably 10 to 60% by mass. Is even more preferable.

Further, in order to obtain a copolymer (P1) of the styrene-based monomer and the diene-based monomer, the styrene-based monomer, the diene-based monomer, an ethylenically unsaturated carboxylic acid monomer, etc. It is also possible to copolymerize with other copolymerizable ethylenically unsaturated monomers.

Other copolymerizable ethylenically unsaturated monomers include ethylenically unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile; ethylenically unsaturated carboxylic acids such as (meth) acrylic acid; and methyl methacrylic acid and the like. Ethylene unsaturated carboxylic acid esters; olefins such as ethylene and propylene; halogen atom-containing monomers such as vinyl chloride and vinylidene chloride; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate; methyl Vinyl ethers such as vinyl ether, ethyl vinyl ether, butyl biel ether; vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, butyl vinyl ketone, hexyl vinyl ketone, isopropenyl vinyl ketone; N-vinylpyrrolidone, vinylpyridine, vinyl imidazole, etc. Examples include heterocyclic-containing vinyl compounds.

<Copolymer of styrene-based monomer and ethylenically unsaturated carboxylic acid ester monomer (P2)>
The copolymer (P2) of the styrene-based monomer and the ethylenically unsaturated carboxylic acid ester monomer (hereinafter, may be simply referred to as “copolymer (P2)”) is a styrene-based monomer. It has a derived structure and a structure derived from an ethylenically unsaturated carboxylic acid ester monomer. The copolymer (P2) is obtained by, for example, emulsion polymerization of a raw material composition containing a styrene-based monomer and an ethylenically unsaturated carboxylic acid ester monomer in an aqueous solvent in the presence of an emulsifier. be able to.

The styrene-based monomer mainly has a role of improving the binding property between the active material and the resin and the binding property between the electrode active material layer and the current collector. In particular, when artificial graphite is used as the active material, the effect can be further exhibited.
The amount of the styrene-based monomer used is preferably 10 to 75% by mass, preferably 30 to 60% by mass, of the total ethylenically unsaturated monomer component forming the copolymer (P2). More preferably, it is 35 to 55% by mass.
When the amount of the styrene-based monomer used is 10% by mass or more, the binding property between the active material and the resin and the binding property between the electrode active material layer and the current collector are improved. Further, by setting the amount of styrene used to 70% by mass or less, the electrode formed from the composition of the present invention is hard to crack (crack is hard to occur).
Examples of the styrene-based monomer include styrene, chlorostyrene, vinyltoluene, t-butylstyrene, vinylbenzoic acid, methyl vinylbenzoate, vinylnaphthalene, chloromethylstyrene, hydroxymethylstyrene, α-methylstyrene and the like. Be done. Of these, styrene or vinyltoluene is preferable, and styrene is more preferable, from the viewpoint of dispersibility of the active material.

The ethylenically unsaturated carboxylic acid ester monomer may or may not have a functional group.
Examples of the ethylenically unsaturated carboxylic acid ester monomer having no functional group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and isopropyl (meth) acrylate. , (Meta) n-butyl acrylate, (meth) iso-butyl acrylate, tert-butyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic Examples thereof include (meth) acrylic acid esters such as lauryl acid acid, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isononyl (meth) acrylate, isoboronyl (meth) acrylate, and benzyl (meth) acrylate. ..

Examples of the ethylenically unsaturated carboxylic acid ester monomer having a functional group include an ethylenically unsaturated carboxylic acid ester monomer having a hydroxy group, a glycidyl group and the like. Specific examples include 2-hydroxyethyl (meth) acrylate, 2-hydroxyalkyl (meth) acrylate such as 2-hydroxypropyl (meth) acrylate, and glycidyl acrylate. Among these, from the viewpoint of ease and durability of emulsion polymerization, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, isobolonyl (meth) acrylate, (meth). ) 2-Hydroxyethyl acrylate is preferred.

The amount of the ethylenically unsaturated carboxylic acid ester monomer used is preferably 25 to 90% by mass of the total ethylenically unsaturated monomer component forming the copolymer (P2), preferably 30 to 65. It is more preferably mass%, and even more preferably 40-55 mass%.
By setting the amount of the ethylenically unsaturated carboxylic acid ester monomer used to 25% by mass or more, the flexibility and heat resistance of the formed electrode can be improved, and by setting it to 90% by mass or less, the active material and the resin can be used. It is possible to improve the binding property with and the binding property between the active material layer and the current collector.

As the monomer forming the copolymer (P2), an ethylenically unsaturated carboxylic acid monomer may be further used.
Examples of the ethylenically unsaturated carboxylic acid monomer include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid, unsaturated dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid, or these unsaturated dicarboxylic acids. Of these, acrylic acid and itaconic acid are preferable. These ethylenically unsaturated carboxylic acid monomers may be used alone or in combination of two or more.

The amount of the ethylenically unsaturated carboxylic acid monomer used is preferably 0.01% by mass or more and 10% by mass or less of the total ethylenically unsaturated monomer component forming the copolymer (P2). , 0.1% by mass or more and 8% by mass or less, and further preferably 0.1% by mass or more and 7% by mass or less. When the ethylenically unsaturated carboxylic acid monomer is 0.01% by mass or more, the emulsion polymerization stability and the mechanical stability are improved. Further, when it is 10% by mass or less, the binding property between the active material and the resin and the binding property between the active material layer and the current collector are good.
Further, it is preferable that the acid value of the copolymer (P2) is within the above range from the viewpoint of production stability.

As the monomer forming the copolymer (P2), a monomer other than the above having at least one polymerizable ethylenically unsaturated group may be used. As such a monomer, ethylenically unsaturated having an amide group such as (meth) acrylamide, N-methylol (meth) acrylamide, (meth) acrylonitrile, vinyl acetate, vinyl propionate, and a functional group such as a nitrile group. Examples thereof include compounds other than the carboxylic acid ester monomer, sodium parastyrene sulfonic acid, and the like.

In the raw material composition of the copolymer (P2) of the styrene-based monomer and the ethylenically unsaturated carboxylic acid ester monomer, in order to further improve the swelling resistance of the dry film to the electrolytic solution solvent, further It can also contain an internal cross-linking agent (internal cross-linking monomer).

The internal cross-linking agent has at least one ethylenically unsaturated bond and has a reactive group that is reactive with the functional group of the above-mentioned monomer, or two or more ethylenically unsaturated bonds. Can be used.

Examples of such an internal cross-linking agent include a cross-linking polyfunctional monomer having two or more unsaturated groups such as divinylbenzene, ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and triallyl cyanurate. , Vinyl trimethoxysilane, vinyl triethoxysilane, γ-methacoxypropyltrimethoxysilane, γ-methacoxypropyltriethoxysilane, and other silane coupling agents having at least one ethylenically unsaturated bond. Of these, divinylbenzene, trimethylolpropane tri (meth) acrylate and γ-methacoxypropyltrimethoxysilane are preferable. These internal cross-linking agents may be used alone or in combination of two or more.

The amount of the internal cross-linking agent used is preferably 0.01 to 5% by mass, preferably 0.01 to 4% by mass, of the total ethylenically unsaturated monomer component forming the copolymer (P2). More preferably, it is more preferably 0.01 to 3% by mass. When the amount of the internal cross-linking agent used is 0.01% by mass or more, the swelling resistance of the dry film to the electrolytic solution can be easily improved, and when it is 5% by mass or less, the deterioration of the emulsion polymerization stability is prevented. it can.

Further, as the monomer forming the copolymer (P2), a reactive emulsifier described later may be used.

<Emulsifier>
As the emulsifier used in the emulsion polymerization, ordinary anionic emulsifiers and nonionic emulsifiers are used.
Examples of the anionic emulsifier include alkylbenzene sulfonates, alkyl sulfates, polyoxyethylene alkyl ether sulfates, fatty acid salts and the like. Examples of the nonionic emulsifier include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene polycyclic finyl ether, polyoxyalkylene alkyl ether, sorbitan fatty acid ester, and polyoxyethylene sorbitan fatty acid ester. These may be used individually by 1 type, and may be used in combination of 2 or more type.
Further, when a reactive emulsifier is used as the emulsifier, bleed-out of the emulsifier is prevented and the mechanical stability of the electrode formed from the composition of the present invention can be improved, which is preferable. Examples of the reactive emulsifier include those represented by the following general formulas (1) to (5).

式中、Ｒはアルキル基、ｍは１０〜４０の整数を示す。

In the formula, R is an alkyl group and m is an integer of 10 to 40.

式中、ｎは１０〜１２の整数、ｍは１０〜４０の整数を示す。

In the formula, n is an integer of 10 to 12, and m is an integer of 10 to 40.

式中、Ｒはアルキル基、ＭはＮＨ_４又はＮａを示す。

In the formula, R represents an alkyl group and M represents NH ₄ or Na.

式中、Ｒはアルキル基を示す。

In the formula, R represents an alkyl group.

式中、Ａは炭素数２又は３のアルキレンオキシド、ｍは１０〜４０の整数を示す。

In the formula, A represents an alkylene oxide having 2 or 3 carbon atoms, and m represents an integer of 10 to 40.

In the case of a non-reactive emulsifier, the preferable amount of the emulsifier is 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the total ethylenically unsaturated monomer component forming the copolymer. It is preferably 0.1 to 2.0 parts by mass, and even more preferably 0.2 to 1.0 parts by mass. In the case of a reactive emulsifier, the content is preferably 0.3 to 5.0% by mass, preferably 0.5% by mass, of the total ethylenically unsaturated monomer component (including the reactive emulsifier) forming the copolymer. It is more preferably ~ 4.0% by mass, and even more preferably 0.5 to 2.0% by mass. The non-reactive emulsifier and the reactive emulsifier may be used alone, but are preferably mixed.

<Initiator>
As the radical polymerization initiator used in the emulsion polymerization, known and commonly used ones can be used, and examples thereof include ammonium persulfate, potassium persulfate, hydrogen peroxide, and t-butyl hydroperoxide. Further, if necessary, these polymerization initiators may be used in combination with a reducing agent such as sodium bisulfite, longalit (sodium hydroxymethanesulfinate), and ascorbic acid for redox polymerization.

Further, in order to adjust the molecular weight of the copolymer (P2), mercaptan, thioglycolic acid and its ester, β-mercaptopropionic acid and its ester and the like may be used at the time of polymerization.

<Polymerization method>
As the emulsification polymerization method, a polymerization method in which the monomers constituting the binder resin (B) are collectively charged, a method in which each component is continuously supplied and polymerized, and the like are applied. The polymerization is usually carried out at a temperature of 30 to 90 ° C. with stirring. By adjusting the pH by adding a basic substance during or after the polymerization of the above-mentioned copolymer, the polymerization stability, mechanical stability, and chemical stability during emulsion polymerization can be improved. As the basic substance used in this case, ammonia, triethylamine, ethanolamine, caustic soda and the like can be used. These may be used individually by 1 type, and may be used in combination of 2 or more type. The pH of the adjusted aqueous emulsion (EM) is preferably 2.5 to 8.0, more preferably 5 to 7.

[Crack inhibitor (C)]
The slurry of the present invention contains a crack inhibitor (C) having a boiling point of 120 ° C. or higher at 1 atm and a solubility in water at 20 ° C. of 10 g / 100 mL or higher. The crack inhibitor (C) is preferably an organic solvent, and its boiling point is preferably 150 ° C. or higher, more preferably 200 ° C. or higher. The solubility in water at 20 ° C. is preferably 20 g / 100 mL or more, and more preferably 50 g / 100 mL or more.
It is considered that when the boiling point of the crack inhibitor (C) is 120 ° C. or higher, the electrode active material layer can be gradually formed while relaxing the stress that tends to cause cracks that occur when the slurry is dried. ..
When the solubility in water at 20 ° C. is 10 g / 100 mL or more, the crack inhibitor (C) has high solubility in water and high hydrophilicity, and becomes the active material (A) which constitutes most of the slurry. It is considered that it is difficult to be absorbed and the fluidity of the slurry can be maintained.
Further, in the present invention, it has been found that the organic solvent having a higher boiling point tends to have better binding properties between active materials and between active materials and current collectors. Although the details are unknown, a high boiling point solvent having a large difference in boiling point from water does not easily attract water during evaporation in the drying step. Since the position of the binder is unlikely to change due to hydrogen bonds accompanying the withdrawal of water, it is considered that the binder can be dried while being uniformly attached to the active material.
The crack inhibitor (C) is not particularly limited as long as it satisfies the boiling point and solubility. As specific examples, N-methylpyrrolidin-2-one (boiling point 202 ° C., mixed with water), ethylene glycol (boiling point 197 ° C., mixed with water), diethylene glycol (boiling point 244 ° C., mixed with water), ethylene glycol monobutyl ether ( Boiling point 171 ° C, mixed with water), 3-methoxy-3-methyl-1-butanol (boiling point 174 ° C, mixed with water), N, N-dimethylformamide (boiling point 153 ° C, mixed with water), dimethyl sulfoxide (boiling point) Solubility in water at 189 ° C and 25 ° C (25.3 g / 100 mL) and the like. Among them, N-methylpyrrolidine-2-one is particularly preferable because it has a particularly high water solubility and a high boiling point.

The content of the crack inhibitor (C) is preferably 10 to 500 parts by mass, more preferably 20 to 400 parts by mass, and further preferably 30 to 300 parts by mass with respect to 100 parts by mass of the binder resin (B). Parts, particularly preferably 100 to 200 parts by mass.

The crack inhibitor (C) preferably contains 0.1 to 20.0 parts by mass, more preferably 0.3 to 10.0 parts by mass, and further preferably 0.3 to 10.0 parts by mass with respect to 100 parts by mass of the non-volatile component of the slurry. Is to include 0.5 to 5.0 parts by mass.

The slurry of the present invention preferably contains the crack inhibitor (C) in an amount of 0.01 to 10% by mass, more preferably 0.10 to 5.0% by mass, and 0.25 to 3.00% by mass. Is even more preferable.

When the electrode is formed by the method described later, the crack inhibitor (C) contained in the slurry of the present invention preferably has a small amount remaining in the electrode. The residual amount of the black inhibitor (C) in the electrode is preferably 0.05% by mass or less, and more preferably 0.01% by mass or less. [Thickener (D)]
The slurry of the present invention may further contain a thickener or the like, if necessary. Thickeners include, for example, carboxymethyl cellulose (CMC), methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, polyacrylic acid, oxidized starch, phosphorylated starch, casein, and salts thereof, arabic rubber, xanthan gum, alginic acid compounds. Etc. can be used. These may be used alone or in combination of two or more.
The thickener is preferably 0.1 to 10.0% by mass, more preferably 0.5 to 5.0% by mass, and further preferably 0.8 to 3.0% by mass with respect to the entire non-volatile component of the slurry.
[Slurry dispersion medium]
The slurry dispersion medium of the present invention is water. It may be pure water or ion-exchanged water. As water, a dispersion medium produced by aqueous emulsion polymerization of the binder resin (B) may be applied as it is. The slurry may contain a dispersion medium other than water. However, the crack inhibitor (C) is not included in the dispersion medium. Examples of other dispersion media include alcohols such as methanol, ethanol and isopropyl alcohol; and ketones such as acetone. When another dispersion medium is used, the water content is preferably 80% by mass or more of the total dispersion medium.

[Other additives]
It is also possible to add a conductive auxiliary agent to the slurry of the present invention. The conductive auxiliary agent may be a material having electrical conductivity between active materials. Examples of conductive auxiliaries include carbon black such as acetylene black, polymer charcoal, and carbon fiber.

(Method of preparing slurry for non-aqueous battery electrodes)
One embodiment of the slurry preparation method of the present invention includes, for example, a method including the following steps.
(I) A step of dispersing, dissolving or kneading the binder resin (B) in a solvent.
(II) A step of adding the active material (A) and additives used as necessary, and further dispersing, dissolving or kneading.
The crack inhibitor (C), thickener (D) and other additives can be mixed in step (I) or in step (II).

Other embodiments of the slurry preparation method of the present invention include, for example, a method including the following steps.
(I) A step of emulsion-polymerizing one or more kinds of ethylenically unsaturated monomers to obtain an aqueous emulsion (EM) of a binder resin (B).
(II) A step of adding the active material (A) and, if necessary, an additive to be used to the aqueous emulsion (EM), and further dispersing and dissolving the emulsion (EM).
The crack inhibitor (C), thickener (D) and other additives can be mixed after step (I) or in step (II).

(Non-aqueous battery electrode)
A non-aqueous battery electrode according to an embodiment of the present invention (hereinafter, may be referred to as “electrode of the present embodiment”.
) Has an electrode active material layer formed from the above-mentioned slurry for non-aqueous battery electrodes of the present invention on the current collector.
The electrode of one embodiment of the present invention can be used as both a positive electrode and a negative electrode of a non-aqueous battery, but is particularly effective when used as a negative electrode. In particular, it is most effective when used as the negative electrode of a lithium ion non-aqueous battery electrode.

The current collector in the electrode of the present embodiment is not particularly limited as long as it is metallic such as iron, copper, aluminum, nickel, and stainless steel. Among these, aluminum is preferable as the current collector for the positive electrode, and copper is preferable as the current collector for the negative electrode.
The shape of the current collector is also not particularly limited, but it is usually preferable to use a sheet-like current collector having a thickness of 0.001 to 0.5 mm.

The electrode of the present embodiment has a current collector and an electrode active material layer formed on the current collector, and the electrode active material layer contains a binder resin (B) and an active material (A). The electrode active material layer is formed by curing (drying) a slurry for non-aqueous battery electrodes.

When the non-aqueous battery electrode of one embodiment of the present invention is a negative electrode, a negative electrode active material layer is formed on the current collector by using the non-aqueous battery electrode slurry of the present invention containing the above-mentioned negative electrode active material. The amount of non-volatile components (the amount of the negative electrode active material layer) formed on the current collector on one side of the slurry is preferably 1 to ²⁰ mg / cm ^{2 on} one side, more preferably 5 to 20 mg / cm ² , and 10 to 15 mg. / Cm ² is more preferred.
When the non-aqueous battery electrode of one embodiment of the present invention is a positive electrode, a positive electrode active material layer is formed on the current collector by using the non-aqueous battery electrode slurry of the present invention containing the above-mentioned positive electrode active material. The amount of non-volatile components (the amount of the positive electrode active material layer) formed on the current collector on one side of the slurry is preferably 10 to 40 mg / cm ^{2 on} one side, more preferably 13 to 30 mg / cm ² , and 15 to 25 mg. / Cm ² is more preferred.

The electrode of one embodiment of the present invention has good binding properties between the active materials due to the binder resin (B), and can prevent cohesive failure of the electrode active material layer. Further, the electrode of the present embodiment can also improve the binding property between the electrode active material layer and the current collector. In particular, by using the slurry for non-aqueous battery electrodes of the present invention, it is possible to obtain an electrode that is less likely to crack even if the slurry is thickly coated to form a thick electrode active material layer. As a result, it is possible to achieve a high energy density of the non-aqueous battery. Such an effect can be made extremely good, especially when copper is used as the current collector.

[Non-aqueous battery]
The non-aqueous battery according to one embodiment of the present invention is a lithium ion non-aqueous battery (hereinafter, may be referred to as "battery of the present embodiment"). The battery of this embodiment is formed by using the non-aqueous battery electrode of one embodiment of the present invention described above. That is, an electrode having a thick electrode active material layer formed by using the slurry for a non-aqueous battery electrode of the present invention and which is hard to crack is used.
For example, the non-aqueous battery of the present embodiment preferably contains the negative electrode active material layer having a total thickness of 10 to 40 mg / cm ² on both sides, and more preferably ²⁰ to 30 mg / cm ² .

The battery of the present embodiment can be manufactured according to a known method by using a positive electrode and a negative electrode, an electrolytic solution, and if necessary, parts such as a separator. As the electrode, the electrode of the present invention described above may be used for both the positive electrode and the negative electrode, or the electrode of the present embodiment described above may be used for either the positive electrode or the negative electrode, but the electrode of the present embodiment described above may be used for the negative electrode. It can be particularly effective when used.
As the outer body of the battery, a metal outer body or an aluminum laminated outer body can be used. The shape of the battery may be any of coin type, button type, sheet type, cylindrical type, square type, flat type and the like. Any known lithium salt can be used as the electrolyte in the electrolytic solution of the battery, and it may be selected according to the type of the active material. For _{example, LiClO 4, LiBF 6, LiPF} 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF 6, LiSbF 6, LiB 10 Cl 10, LiAlCl 4, LiCl, LiBr, LiB (C 2 H 5) 4, CF 3 Examples thereof include SO ₃ Li, CH ₃ SO ₃ Li, LiCF ₃ SO ₃ , LiC ₄ F ₉ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, and lower fatty acid lithium carboxylate.

The solvent for dissolving the electrolyte is not particularly limited as long as it is usually used as a liquid for dissolving the electrolyte, and ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), and dimethyl carbonate ( Carbonate compounds such as DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC), vinylene carbonate (VC); lactone compounds such as γ-butyrolactone and γ-valerolactone; trimethoxymethane, 1,2-dimethoxyethane, Ether compounds such as diethyl ether, 2-ethoxyethane, tetrahydrofuran, 2-methyltetraxide; sulfoxide compounds such as dimethylsulfoxide; oxolane compounds such as 1,3-dioxolane and 4-methyl-1,3-dioxolane; acetonitrile, nitromethane, Nitrogen-containing compounds such as formamide and dimethylformamide; organic acid ester compounds such as methyl formate, methyl acetate, ethyl acetate, butyl acetate, methyl propionate and ethyl propionate; phosphate triester and diglyme compounds; triglime compounds; sulfolane, methyl Sulfolane compounds such as sulfolane; oxazolidinone compounds such as 3-methyl-2-oxazolidinone; sulton compounds such as 1,3-propanesulton, 1,4-butanesulton, and naphthalusulton; and the like can be mentioned. These may be used individually by 1 type, or may be used in combination of 2 or more type.
The non-aqueous battery according to one embodiment of the present invention may be a lithium ion non-aqueous battery.

(Manufacturing method for non-aqueous battery electrodes)
The method for manufacturing a non-aqueous battery electrode according to an embodiment of the present invention includes the following steps.
(III) A step of forming an electrode active material layer by applying the slurry for non-aqueous battery electrodes obtained in the above steps (I) and (II) onto a current collector and drying the slurry.
The electrode of the present embodiment can be obtained, for example, by applying the above-mentioned slurry for a non-aqueous battery electrode of the present invention on a current collector and drying it.
As the coating method, general methods can be used, for example, the reverse roll method, the direct roll method, the doctor blade method, the knife method, the extrusion method, the curtain method, the gravure method, the bar method, the dip method and the squeeze method. I can give it. Among these, the doctor blade method, the knife method, and the like, from the viewpoint that the surface condition of the electrode active material layer can be improved by selecting the coating method according to various physical properties such as viscosity of the slurry of the present invention and the drying property. Alternatively, the extrusion method is preferable. The drying temperature can be selected from 25 ° C. to 180 ° C. according to various physical properties and drying properties of the resin contained in the slurry and the drying time. From the viewpoint of work efficiency, for example, 50 ° C to 150 ° C is preferable, and 60 ° C to 120 ° C is more preferable.
Further, the electrode of the present embodiment can be pressed as needed after the electrode active material layer is formed. As a pressing method, a general method can be used, but a die pressing method and a calendar pressing method are particularly preferable. The press pressure is not particularly limited, but is preferably 0.2 to 3 t / cm ² .

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Unless otherwise specified, "parts" and "%" in Examples and Comparative Examples indicate parts by mass and% by mass, respectively.
In addition, the materials used in Examples and Comparative Examples, the slurry for non-aqueous battery electrodes obtained in Examples and Comparative Examples, and the electrodes for non-aqueous batteries were measured and evaluated as follows. The results are shown in Table 2 or 3.

[Evaluation method]
(Non-volatile content of aqueous emulsion (EM) and non-volatile content of slurry)
It was calculated by weighing 1 g of an aqueous emulsion (EM) or a slurry as an evaluation sample on an aluminum dish having a diameter of 5 cm, drying in the air at 105 ° C. for 1 hour, and weighing the balance.

(viscosity)
Using a Brookfield type rotational viscometer, the liquid temperature was 23 ° C., the rotation speed was 60 rpm, and No. 2 or No. Measured with 3 rotors.

(PH)
The pH (23 ° C.) of the aqueous emulsion (EM) was measured by the glass electrode method. A pH meter (F-52, manufactured by HORIBA, Ltd.) was used for pH measurement.

(Average particle size of resin particles dispersed in an aqueous emulsion (EM))
The average particle size (50% median diameter on a volume basis) was measured with a UPA type particle size distribution measuring device (manufactured by Microtrac Bell Co., Ltd.).
(Acid value)
The measured acid value (mgKOH / g) was determined in terms of solid content in accordance with the potentiometric titration method of JIS K 0070.

(Slurry appearance)
A slurry for a non-aqueous battery electrode (negative electrode) is obtained by mixing the components described below, and after 10 minutes have passed, visually observe the mixture, and those in which separation and sediment are observed in the liquid and those in which there is no fluidity are x, uniformly. Those that are dispersed are marked with ○.

(Appearance of electrodes)
After the electrode was manufactured, the surface was visually observed, and those with cracks were marked with x and those without cracks were marked with ◯.

(Adhesion of electrodes)
The prepared negative electrode was left at 23 ° C. and 50% RH for 24 hours as a test piece. The peel strength between the active material layer of the test piece and the current collector was measured based on JIS K6854-2. The slurry-coated surface of the test piece and the SUS plate were bonded to each other using double-sided tape, and 180 ° peeling was performed (peeling width 25 mm, peeling speed 100 mm / min), and the peeling strength was measured. When the peel strength is low, it means that the active material layer is easily coagulated and broken, and the binding property between the active materials and between the active material and the current collector is low.

[Synthesis example]
(Synthesis of binder resin B-1)
In a separable flask having a cooling tube, a thermometer, a stirrer, and a dropping funnel, 32.6 parts by mass of ion-exchanged water and a reactive anionic emulsifier represented by the above general formula (4) (manufactured by Sanyo Kasei Kogyo Co., Ltd., trade name) Eleminor JS-20, active ingredient 40% by mass) 0.11 parts by mass, non-reactive anionic emulsifier (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name Hytenol 08E, polyoxyethylene alkyl ether sulfate) 0. 02 parts by mass was charged, and submerged bubbling with nitrogen gas was carried out for 1 hour, and then the temperature was raised to 75 ° C.
Next, 0.48 parts by mass of the reactive anionic emulsifier represented by the above general formula (4), a non-reactive anionic emulsifier (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: Hytenol 08E, polyoxyethylene alkyl ether) Sulfonic acid ester salt) 0.17 parts by mass, styrene 49.2 parts by mass, 2-ethylhexyl acrylate 43.1 parts by mass, 2-hydroxyethyl methacrylate 1.90 parts by mass, acrylic acid 1.90 parts by mass, parastyrene A monomeric emulsion prepared by premixing 0.60 parts by mass of sodium sulfonate, 0.04 parts by mass of divinylbenzene and 67.9 parts by mass of ion-exchanged water was added dropwise over 3 hours. At the same time, 0.40 parts by mass of potassium persulfate dissolved in 9.30 parts by mass of ion-exchanged water as a polymerization initiator was dropwise-polymerized at 80 ° C. over 3 hours. After completion of the dropping, the mixture was aged for 2 hours and then cooled, and 2.10 parts by mass of aqueous ammonia was added to obtain an anionic aqueous emulsion EM1 in which the binder resin B-1 was dispersed. The obtained anionic aqueous emulsion EM1 has a pH of 5.0, a viscosity of 40 mPa · s, a proportion (nonvolatile content) of binder resin B-1 in the aqueous emulsion of 40% by mass, and an average particle size of the resin particles in the emulsion is 250 nm. The binder resin had a glass transition temperature of 15 ° C. and an acid value of 40 mgKOH / g.

(Synthesis of binder resin B-2)
As a monomer, 52.4 parts by mass of styrene, 40.6 parts by mass of 2-ethylhexyl acrylate, 3.80 parts by mass of acrylate, 1.90 parts by mass of itaconic acid, 0.60 parts by mass of sodium parastyrene sulfonate, and divinyl. An anionic aqueous emulsion EM2 in which the binder resin B-2 was dispersed was obtained in the same manner as the aqueous emulsion EM1 except that 0.67 parts by mass of benzene was used. The obtained anionic aqueous emulsion EM2 has a non-volatile content of 40% by mass, a pH of 7.0, and a viscosity of 60 mPa · s, the average particle size of the resin particles in the aqueous emulsion is 300 nm, and the binder resin B-2 has a glass transition temperature. The acid value was 40 mgKOH / g at 15 ° C.

(Binder resin B-3)
As an anionic aqueous emulsion EM3 in which the binder resin B-3 is dispersed, BM-400B manufactured by Nippon Zeon Co., Ltd. (styrene-butadiene rubber having 69.8% by mass of styrene and 30% by mass of butadiene, 40% by mass of non-volatile content, pH 7.0, A viscosity of 11 mPa · s, an average particle diameter of resin particles in an aqueous emulsion of 190 nm, a glass transition temperature of −7 ° C., and an acid value of 25 mgKOH / g) were prepared.

(Example 1)
<Preparation of slurry for negative electrode>
As an active material (artificial graphite SCMG (registered trademark) -XRs, manufactured by Showa Denko, particle diameter 12 μm, specific surface area 2.5 m ² / g), carbon black C-65 (manufactured by Timcal), thickener (D) After mixing 2% by mass aqueous solution of CMC (weight average molecular weight 3 million, degree of substitution 0.9) and water at the ratio shown in Table 1 (step 1), emulsion EM1 and crack inhibitor (C) are used as the binder resin (B). ), NMP and water were mixed at the ratio shown in Table 1 (step 2) to obtain a slurry for the non-aqueous battery electrode (negative electrode) of Example 1. The evaluation results are shown in Table 2.

(Preparation of negative electrode)
A slurry for a non-aqueous battery electrode (negative electrode) was applied on one side of a copper foil as a current collector so that the Wet thickness was 280 μm, heated and dried at 60 ° C. for 2 minutes, and then dried at 100 ° C. for 2 minutes. ..
After that, the other side was similarly coated and dried. Nonvolatile component of the slurry of one side that is formed on the current collector 12 mg / cm ^2, to obtain an electrode of 24 mg / cm ² on both sides. The evaluation results are shown in Table 2.

(Examples 2 to 10) (Comparative Examples 1 to 8)
The slurry for non-aqueous battery electrodes and the non-aqueous emulsion are the same as in Example 1 except that the aqueous emulsion (EM) is changed to the formulations shown in Tables 2 and 3 as the crack inhibitor (C) and the binder resin (B). A battery electrode was obtained. The evaluation results are shown in Tables 2 and 3.
The crack preventives used are as follows.
NMP: N-methylpyrrolidine-2-one (manufactured by Wako Pure Chemical Industries, Ltd.)
Butyl cellosolve: ethylene glycol monobutyl ether (manufactured by Dow Chemical Japan, Ltd.)
EG: Ethylene glycol (manufactured by Maruzen Petrochemical Co., Ltd.)
DEG: Diethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.)
DMF: N, N-dimethylformamide (manufactured by Wako Pure Chemical Industries, Ltd.)
DMSO: Dimethyl sulfoxide (manufactured by Wako Pure Chemical Industries, Ltd.)
Solfit: 3-Methoxy-3-methyl-1-butanol (manufactured by Kuraray Co., Ltd.)
IPA: Isopropyl alcohol (manufactured by Tokuyama Corporation)
n-Butanol: 1-Butanol (manufactured by Mitsubishi Chemical Corporation)
Benzyl alcohol: Benzyl alcohol (manufactured by Ark Co., Ltd.)
Phenoxyethanol-SP: Phenoxyethanol (manufactured by Yokkaichi Chemical Co., Ltd.)
Weidinol EHP01: Propylene glycol-mono-2-ethylhexanoate (manufactured by Yokkaichi Chemical Co., Ltd.)
Texanol: 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoart (manufactured by Chisso Corporation)
Benzoflex 9-88: Dipropylene Glycol Dibenzoate (manufactured by Velsil Chemical)

(Examples 11 to 12) (Comparative Examples 9 to 10)
Non-aqueous battery electrode slurry and non-aqueous battery electrode in the same manner as in Example 1 and Comparative Example 1 except that the crack inhibitor (C) and the aqueous emulsion (EM) were changed to the formulations shown in Tables 2 and 3. Got The evaluation results are shown in Tables 2 and 3.

As is clear from the evaluation results of the slurry for non-aqueous battery electrodes shown in Tables 2 and 3 and the evaluation results of the non-aqueous battery electrodes prepared using the same, the implementation using the slurry for non-aqueous battery electrodes of the present invention. In Examples 1 to 12, the electrodes were not cracked and the adhesion to the electrodes was high. Among them, Examples 1 to 4, 7, 11 and 12 using a crack inhibitor having a boiling point of more than 200 ° C. were particularly excellent in electrode adhesion.

Claims (14)

Active material (A) for non-aqueous battery electrodes and
Binder resin (B) and
Crack inhibitor (C) and
A slurry for non-aqueous battery electrodes containing water.
The crack inhibitor (C) is a slurry for non-aqueous battery electrodes having a boiling point of 120 ° C. or higher at 1 atm and a solubility in water at 20 ° C. of 10 g / 100 mL or higher. The crack inhibitor (C) is selected from N-methylpyrrolidin-2-one, ethylene glycol, diethylene glycol, ethylene glycol monobutyl ether, 3-methoxy-3-methyl-1-butanol, N, N-dimethylformamide, and dimethyl sulfoxide. The slurry for non-aqueous battery electrodes according to claim 1, which is at least one of the slurry. The slurry for a non-aqueous battery electrode according to claim 1, wherein the crack inhibitor (C) is an organic solvent having a boiling point of 150 ° C. or higher at 1 atm. The slurry for a non-aqueous battery electrode according to claim 1, wherein the crack inhibitor (C) is an organic solvent having a boiling point of more than 200 ° C. at 1 atm. The slurry for a non-aqueous battery electrode according to any one of claims 1 to 4, which contains 10 to 500 parts by mass of the crack inhibitor (C) with respect to 100 parts by mass of the binder resin (B). The slurry for a non-aqueous battery electrode according to any one of claims 1 to 5, further comprising a thickener (D). The slurry for non-aqueous battery electrodes according to claim 6, wherein the thickener (D) is carboxymethyl cellulose (CMC). The binder resin (B) is a copolymer (P1) of a styrene-based monomer and a diene-based monomer, and a copolymer of a styrene-based monomer and an ethylenically unsaturated carboxylic acid ester monomer. The slurry for a non-aqueous battery electrode according to any one of claims 1 to 7, which is at least one selected from (P2). The binder resin (B) contains a copolymer (P1) of a styrene-based monomer and a diene-based monomer, and is styrene-based among all ethylenically unsaturated monomer components constituting the copolymer. The slurry for a non-aqueous battery electrode according to any one of claims 1 to 8, wherein the monomer component is 5 to 70% by mass and the diene-based monomer component is 30 to 95% by mass. The non-aqueous system according to any one of claims 1 to 9, wherein the binder resin (B) contains a copolymer (P2) of a styrene-based monomer and an ethylenically unsaturated carboxylic acid ester monomer. Styrene for battery electrodes. Any of claims 1 to 10, wherein the binder resin (B) contains a copolymer of a styrene-based monomer, an ethylenically unsaturated carboxylic acid ester monomer, and an ethylenically unsaturated carboxylic acid monomer. The slurry for a non-aqueous battery electrode according to item 1. The amount of styrene used in the binder resin (B) is 10 to 70% by mass of the total ethylenically unsaturated monomer component forming the copolymer.
The amount of the ethylenically unsaturated carboxylic acid ester monomer used is 25 to 85% by mass of the total ethylenically unsaturated monomer component forming the copolymer.
The non-aqueous battery according to claim 11, wherein the amount of the ethylenically unsaturated carboxylic acid monomer used is 0.01 to 10% by mass of the total ethylenically unsaturated monomer component forming the copolymer. Slurry for electrodes. A method for producing a non-aqueous battery electrode, which comprises a step of applying the slurry according to any one of claims 1 to 12 onto a current collector and drying the slurry. A method for manufacturing a non-aqueous battery according to claim 13, wherein the method for manufacturing the non-aqueous battery electrode is provided.