WO2019155980A1 - Slurry for non-aqueous cell electrode, and manufacturing method for non-aqueous cell electrode and non-aqueous cell - Google Patents

Abstract

Provided is a slurry for a non-aqueous cell electrode, with which it is possible to obtain an electrode that is less susceptible to cracking even when a slurry is thickly applied and an electrode active material layer is thickly formed. This slurry for a non-aqueous cell electrode is characterized in containing a non-aqueous cell electrode active material (A), a binder resin (B), an anti-cracking agent (C), and water, the anti-cracking agent (C) having a boiling point at 1 atm of 120°C or higher and a solubility in water at 20°C of 10 g/100 mL or higher.

Description

Non-aqueous battery electrode slurry, and non-aqueous battery electrode and non-aqueous battery manufacturing method

The present invention relates to a slurry for a non-aqueous battery electrode, and a non-aqueous battery electrode and a method for producing a non-aqueous battery.
This application claims priority on February 9, 2018 based on Japanese Patent Application No. 2018-022334 for which it applied to Japan, and uses the content here.

In recent years, lithium ion non-aqueous batteries have attracted attention from the viewpoints of downsizing 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 cobaltate as an active material, a negative electrode using a carbon material such as graphite as an active material, and an electrolyte solvent mainly composed of carbonates. In the lithium ion non-aqueous battery, charging / discharging of the battery is performed as lithium ions move between the positive electrode and the negative electrode.
The positive electrode can be obtained by forming a positive electrode layer on the surface of a positive electrode current collector such as an aluminum foil from a composition containing a positive electrode active material such as a metal oxide and a binder. The negative electrode is obtained by forming a negative electrode layer on the surface of a negative electrode current collector such as a copper foil from a composition containing a negative electrode active material such as graphite and a binder. Accordingly, 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) binder using an organic solvent-based N-methylpyrrolidin-2-one (NMP) as a solvent is well known (for example, see Patent Document 1). However, this binder has a low binding property between the active materials and between the active material and the current collector, and a large amount of binder is required for actual use, resulting in a disadvantage that the capacity of the nonaqueous battery is reduced. In addition, since NMP, which is an expensive organic solvent, is used for the binder, there are problems in the price of the final product and in the maintenance of the working environment when the slurry or current collector is produced.

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

Recently, from the viewpoint of being environmentally friendly, lithium ion non-aqueous batteries with high voltage, high capacity, and high energy density have been strongly demanded as non-aqueous batteries for electric vehicles or hybrid vehicles.
As measures for improving these, there is a method in which a slurry is applied to the electrode current collector to form a thick electrode active material layer.
However, if the coating is thick, cracks are likely to occur in the electrodes, and the battery performance is not necessarily improved.

JP-A-10-298386 JP-A-5-74461 JP-A-8-250123 JP 2011-204573 A JP 2011-243464 A

The present invention solves the problems of the prior art, is of an aqueous dispersion system, has good binding properties between active materials and between the active material and a current collector, and does not easily 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 hardly peeled from the surface of a current collector, a non-aqueous battery electrode using the slurry, and a method for producing a non-aqueous battery.

The present inventors have intensively studied to solve the above problems, and paying attention to the fact that the occurrence of cracks can be prevented by adding a specific organic solvent to the water dispersion slurry as a crack preventing agent. It came to solve.
That is, the present invention includes the following aspects.

[1] A non-aqueous battery electrode slurry containing a non-aqueous battery electrode active material (A), a binder resin (B), a crack inhibitor (C), and water,
The anti-cracking agent (C) has a boiling point at 1 atm of 120 ° C. or higher and a solubility in water at 20 ° C. of 10 g / 100 mL or higher.
[2] The crack preventing agent (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 nonaqueous battery electrodes according to [1], which is at least one selected from sulfoxides.
[3] The non-aqueous battery electrode slurry according to [1], wherein the crack preventing agent (C) is an organic solvent having a boiling point of 150 ° C. or higher at 1 atmosphere.
[4] The non-aqueous battery electrode slurry according to claim 1, wherein the crack preventing agent (C) is an organic solvent having a boiling point of more than 200 ° C. at 1 atmosphere.
[5] The slurry for non-aqueous battery electrodes according to any one of [1] to [4], comprising 10 to 500 parts by mass of the crack preventing agent (C) with respect to 100 parts by mass of the binder resin (B).
[6] The slurry for nonaqueous battery electrodes according to any one of [1] to [5], further comprising a thickener (D).
[7] The slurry for nonaqueous battery electrodes according to [6], wherein the thickener (D) is carboxymethylcellulose (CMC).
[8] The binder resin (B) is a copolymer of a styrene monomer and a diene monomer, and a copolymer of a styrene monomer and an ethylenically unsaturated carboxylic acid ester monomer. The slurry for nonaqueous battery electrodes according to any one of [1] to [7], which is at least one selected from the group consisting of:
[9] The binder resin (B) includes a copolymer of a styrene monomer and a diene monomer, and is a styrene resin among all ethylenically unsaturated monomer components constituting the copolymer. The slurry for nonaqueous battery electrodes according to any one of [1] to [8], wherein the monomer component is 5 to 70% by mass and the diene monomer component is 30 to 95% by mass.
[10] The nonaqueous system according to any one of [1] to [9], wherein the binder resin (B) includes a copolymer of a styrene monomer and an ethylenically unsaturated carboxylic acid ester monomer. Slurry for battery electrodes.
[11] The binder resin (B) includes a copolymer of a styrene monomer, an ethylenically unsaturated carboxylic acid ester monomer, and an ethylenically unsaturated carboxylic acid monomer. 10] The slurry for non-aqueous battery electrodes according to any one of [10].
[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,
[11] The nonaqueous 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 components forming the copolymer. Electrode slurry.
[13] A method for producing a nonaqueous battery electrode, comprising 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 producing a nonaqueous battery, comprising the process for producing a nonaqueous battery electrode according to [13].

By using the slurry for a non-aqueous battery electrode of the present invention, it is possible to obtain an electrode that does not easily crack even if the slurry is applied thickly 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 preventing agent (C), and water as essential components. The anti-cracking agent (C) has a boiling point of 120 ° C. or more at 1 atm and a solubility in water at 20 ° C. of 10 g / 100 mL or more. Further, (D) a thickener may be included.
In this specification, “(meth) acryl” is a generic term for acrylic and methacrylic, and “(meth) acrylate” is a generic term for acrylate and methacrylate.

[Active material (A)]
The slurry for nonaqueous 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 a positive electrode active material or a negative electrode active material. In the slurry for nonaqueous battery electrodes of one embodiment of the present invention, the active material (A) is a negative electrode active material. When the negative electrode active material is used as the active material (A), the effect is easily exhibited.
The shape of the active material is not particularly limited, and a spherical shape, a flake shape, or the like can be used. The average particle diameter (50% median diameter on a volume basis) of the active material is preferably 5 to 100 μm, more preferably 10 to 50 μm, more preferably 15 to 30 μm from the viewpoint of dispersibility of the active material. More preferably it is. The volume-based 50% median diameter can be calculated by a laser diffraction method.
The BET specific surface area of the active material is preferably 0.1 to 100 m ² / g, more preferably 0.5 to 50 m ² / g, from the viewpoint of dispersibility of the active material, and 1.0 to More preferably, it is 30 m ² / g. In addition, a BET specific surface area can be obtained from a specific surface area measurement (according to JIS Z8830) by a BET nitrogen adsorption method.

Examples of the positive electrode active material include metal composite oxides, for example, metal composite oxides containing at least one metal selected from lithium and iron, cobalt, nickel, and manganese. Preferably, Li _x M _y1 O ₂ (wherein M represents at least one kind of transition metal, preferably Co, Mn or Ni, and 1.10>x> 0.05, 1 ≧ y1> 0 Li _x M _y2 O ₄ (where M represents one or more transition metals, preferably Mn or Ni, and 1.10>x> 0.05, 2 ≧ y2> 0), or Li _x M _y1 PO ₄ (where M represents one or more transition metals, preferably at least one of Fe, Co, Mn, or Ni, and 1.10>x> 0.05, 1 ≧ y1> 0 ) And the like. 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), and composite oxides represented by LiMn ₂ O ₄ , LiFePO _{4, and the} like.

The negative electrode active material is not particularly limited as long as it can electrochemically occlude and release metal ions (for example, lithium ions). Specific examples include carbonaceous materials, metal composite oxides, silicon compounds, and the like.
Examples of the carbonaceous material include graphites such as artificial graphite and natural graphite; cokes such as petroleum coke, pitch coke and coal coke. As the metal composite oxide, for example, lithium titanate or the like can be used. As the silicon compound, silicon, silicon oxide, or the like can be used. When these active materials are used, extremely remarkable effects can be exhibited.
Among these active materials, from the viewpoint of improving the binding property, carbonaceous materials, particularly graphites or cokes in the carbonaceous materials are preferable. Among these, from the viewpoint of energy density per volume, it is more preferable to use graphites such as artificial graphite and natural graphite. Among active materials other than carbonaceous materials, lithium titanate such as Li ₄ Ti ₅ O ₁₂ , silicon, and the like are also preferable from the viewpoint of energy density per volume.
These active materials may be used alone or in combination of two or more.
The content ratio of the active material in the nonvolatile 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%. More preferably, it is ˜98.0% by mass. The nonvolatile component of the slurry is a component that remains after the slurry is dried at 105 ° C. for 1 hour in the air. Further, the “nonvolatile content of the slurry” is the ratio of the nonvolatile component contained in the slurry.

[Binder resin (B)]
The slurry for non-aqueous battery electrodes of the present invention contains a binder resin (B) as an essential component.
The content ratio of the binder resin (B) in the nonvolatile 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, More preferably, it is 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 it may be a polymer of one or more ethylenically unsaturated monomers. preferable.

From the viewpoint of making the electrode formed from the slurry of the present invention difficult to break, 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, 15 More preferably, the temperature is set to ° C or lower. From the viewpoint of handleability, the binder resin (B) preferably has a glass transition temperature of −20 ° C. or higher.

The glass transition temperature of the binder resin (B) is a glass of each homopolymer of ethylenically unsaturated monomers M _i (i = 1, 2,..., I) used for the polymerization of the binder resin (B). From the transition temperature Tg _i (i = 1, 2,..., I) and the respective weight fractions X _i (i = 1, 2,..., I) of the ethylenically unsaturated monomer M _i. It can be calculated as a theoretical value by the following formula (I).

1 / Tg = Σ (X _i / Tg _i ) (I)

More preferably, the binder resin (B) is a raw material for slurry that is dispersed in an aqueous emulsion (EM) containing water as a dispersion medium.

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 emulsion (EM) is prepared by emulsion polymerization using a polymerizable monomer and an emulsifier that form the 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 still more preferably 50 mgKOH / g or less.
The content of the binder resin (B) in the aqueous emulsion (EM), that is, the nonvolatile content of the aqueous emulsion (EM) is preferably 1 to 60% by mass, and more preferably 1 to 55% by mass.

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

<Copolymer of styrene monomer and diene monomer (P1)>
A copolymer (P1) of a styrene monomer and a diene monomer (hereinafter sometimes simply referred to as “copolymer (P1)”) is styrene, chlorostyrene, vinyltoluene, t- Structural units derived from styrenic 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 monomer and a diene monomer can be obtained, for example, by emulsion polymerization of 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 monomer and the diene monomer, the proportion of the structural unit derived from the diene monomer is preferably 30 to 95% by mass, more preferably 40 to 90% by mass. More preferably, it is 50 to 70% by mass. That is, the proportion of the diene monomer contained in the raw material for producing the copolymer (P1) of the styrene monomer and the diene monomer is preferably 30 to 95% by mass or more, more preferably It is 40 to 90% by mass, more preferably 50 to 70% by mass.
The proportion of the structural unit derived from the styrene monomer in the copolymer (P1) of the styrene monomer and the diene monomer is preferably 5 to 70% by mass, and more preferably 10 to 60% by mass. . That is, the ratio of the styrene monomer contained in the raw material for producing the copolymer (P1) of the styrene monomer and the diene monomer is preferably 5 to 70% by mass, and 10 to 60% by mass. Is more preferable.

In order to obtain a copolymer (P1) of a styrene monomer and a diene monomer, the styrene monomer, the diene 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; methyl methacrylate and the like Ethylenically 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 and vinyl benzoate; methyl Vinyl ethers such as vinyl ether, ethyl vinyl ether, butyl vinyl ether; vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, butyl vinyl ketone, hexyl vinyl ketone, isopropenyl vinyl ketone; N-vinyl pyrrolidone, vinyl pyridine, vinyl Heterocycle-containing vinyl compounds and imidazole.

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

The styrenic 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 monomer used is preferably 10 to 75% by mass, and preferably 30 to 60% by mass, based on the total ethylenically unsaturated monomer component forming the copolymer (P2). More preferred is 35 to 55% by mass.
By making the usage-amount of a styrene-type monomer 10 mass% or more, the binding property of an active material and resin and the binding property of an electrode active material layer and a collector become favorable. Moreover, the electrode formed from the composition of this invention is hard to be cracked by making the usage-amount of styrene 70 mass% or less (it is hard to produce a crack).
Examples of the styrene monomer include styrene, chlorostyrene, vinyl toluene, t-butyl styrene, vinyl benzoic acid, methyl vinyl benzoate, vinyl naphthalene, chloromethyl styrene, hydroxymethyl styrene, α-methyl styrene, and the like. It is done. Of these, styrene or vinyltoluene is preferable from the viewpoint of dispersibility of the active material, and styrene is more preferable.

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. , N-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acryl (Meth) acrylic acid esters such as lauryl acid, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isononyl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, etc. .

Examples of the ethylenically unsaturated carboxylic acid ester monomer having a functional group include ethylenically unsaturated carboxylic acid ester monomers 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, glycidyl acrylate, and the like. Among these, from the viewpoint of ease of emulsion polymerization and durability, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (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%. More preferably, it is more preferably 40% to 55% by weight.
By making the use amount of the ethylenically unsaturated carboxylic acid ester monomer 25% by mass or more, the flexibility and heat resistance of the formed electrode can be improved, and by making it 90% by mass or less, the active material and the resin The binding property between the active material layer and the current collector can be improved.

As a monomer for 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 unsaturated dicarboxylic acids thereof. Of these, and among them, acrylic acid and itaconic acid are preferable. These ethylenically unsaturated carboxylic acid monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

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). It is more preferably 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, emulsion polymerization stability and mechanical stability are improved. Moreover, if it is 10 mass% or less, the binding property of an active material and resin and the binding property of an active material layer and a collector are favorable.
Moreover, it is preferable from the surface of manufacturing stability that the acid value of a copolymer (P2) shall be in the said range.

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

In the raw material composition of the copolymer of styrene monomer and ethylenically unsaturated carboxylic acid ester monomer (P2), in order to further improve the swelling resistance of the dry film to the electrolyte solvent, An internal cross-linking agent (internal cross-linkable monomer) can also be included.

The internal cross-linking agent has at least one ethylenically unsaturated bond and has a reactive group reactive with the functional group of the above-described monomer, or two or more ethylenically unsaturated bonds The thing which has can be used.

As such an internal crosslinking agent, a crosslinkable polyfunctional monomer having two or more unsaturated groups such as divinylbenzene, ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, triallyl cyanurate, etc. Silane coupling agents having at least one ethylenically unsaturated bond such as vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, and the like. Of these, divinylbenzene, trimethylolpropane tri (meth) acrylate and γ-methacryloxypropyltrimethoxysilane are preferred. These internal cross-linking agents may be used alone or in combination of two or more.

The amount of the internal crosslinking agent used is preferably 0.01 to 5% by mass, preferably 0.01 to 4% by mass, based on the total ethylenically unsaturated monomer component forming the copolymer (P2). More preferred is 0.01 to 3% by mass. By making the amount of the internal crosslinking agent used 0.01% by mass or more, it is easy to improve the swelling resistance of the dry film against the electrolytic solution, and by making it 5% by mass or less, a decrease in emulsion polymerization stability is prevented. it can.

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

<Emulsifier>
As an emulsifier used in the emulsion polymerization, a normal anionic emulsifier and a nonionic emulsifier are used.
Examples of the anionic emulsifier include alkylbenzene sulfonate, alkyl sulfate ester salt, polyoxyethylene alkyl ether sulfate ester salt, fatty acid salt 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, polyoxyethylene sorbitan fatty acid ester and the like. These may be used individually by 1 type and may be used in combination of 2 or more type.
In addition, if a reactive emulsifier is used as the emulsifier, the bleed-out of the emulsifier is prevented, which is preferable in that the mechanical stability of the electrode formed from the composition of the present invention can be improved. Examples of the reactive emulsifier include those represented by the following general formulas (1) to (5).

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

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

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

In the formula, R represents an alkyl group.

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 preferred 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, more preferably 0.2 to 1.0 part by mass. In the case of a reactive emulsifier, it is preferably 0.3 to 5.0% by mass of the total ethylenically unsaturated monomer components (including the reactive emulsifier) forming the copolymer, It is more preferably from -4.0% by mass, and even more preferably from 0.5-2.0% by mass. Moreover, although a non-reactive emulsifier and a reactive emulsifier may each be used independently, it is preferable to mix and use.

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

In order to adjust the molecular weight of the copolymer (P2), mercaptan, thioglycolic acid and its ester, β-mercaptopropionic acid and its ester may be used during polymerization.

<Polymerization method>
As the emulsion polymerization method, a polymerization method in which the monomers constituting the binder resin (B) are charged all at once, a method in which polymerization is performed while continuously supplying each component, and the like are applied. The polymerization is usually carried out at a temperature of 30 to 90 ° C. with stirring. The polymerization stability, mechanical stability, and chemical stability during emulsion polymerization can be improved by adding a basic substance during the polymerization of the copolymer or after completion of the polymerization to adjust the pH. 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 prevention agent (C)]
The slurry of this invention contains the crack prevention agent (C) whose boiling point in 1 atmosphere is 120 degreeC or more, and the solubility to water in 20 degreeC is 10 g / 100mL or more. The crack preventing agent (C) is preferably an organic solvent, and the boiling point thereof is preferably 150 ° C. or higher, more preferably higher than 200 ° C. 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 preventing agent (C) is 120 ° C. or higher, the electrode active material layer can be gradually formed while relaxing the stress that tends to cause cracking when the slurry is dried. .
When the solubility in water at 20 ° C. is 10 g / 100 mL or more, the anti-cracking agent (C) has high solubility in water and high hydrophilicity to the active material (A) constituting most of the slurry. It is considered that it is difficult to absorb and the fluidity of the slurry can be maintained.
Further, in the present invention, it has been found that an organic solvent having a higher boiling point tends to have better binding properties between active materials and between an active material and a current collector. Although details are unknown, a high-boiling solvent having a large difference in boiling point from water is less likely to take water during evaporation in the drying process. It is considered that the binder can be dried while uniformly adhering to the active material because the change in the position of the binder due to hydrogen bonding accompanying the water pull-in hardly occurs.
The crack inhibitor (C) is not particularly limited as long as it satisfies the boiling point and solubility. Specific examples include N-methylpyrrolidin-2-one (boiling point 202 ° C., miscible with water), ethylene glycol (boiling point 197 ° C., miscible with water), diethylene glycol (boiling point 244 ° C., miscible with water), ethylene glycol monobutyl ether ( Boiling point 171 ° C, miscible with water), 3-methoxy-3-methyl-1-butanol (boiling point 174 ° C, miscible with water), N, N-dimethylformamide (boiling point 153 ° C, miscible with water), dimethyl sulfoxide (boiling point) And the solubility in water at 189 ° C. and 25 ° C. 25.3 g / 100 mL). Among these, N-methylpyrrolidin-2-one is particularly preferable because of its high water solubility and high boiling point.

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

The crack preventing agent (C) is preferably contained in an amount of 0.1 to 20.0 parts by mass, more preferably 0.3 to 10.0 parts by mass, and still more preferably 100 parts by mass of the nonvolatile component of the slurry. Is 0.5 to 5.0 parts by mass.

The slurry of the present invention preferably contains 0.01 to 10% by mass of the crack preventing agent (C), more preferably 0.10 to 5.0% by mass, and 0.20 to 3.00% by mass. More preferably. *

When the electrode is formed by the method described later, it is preferable that the amount of the crack preventing agent (C) contained in the slurry of the present invention is small. 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 this invention can further contain a thickener etc. as needed. Examples of the thickener include carboxymethyl cellulose (CMC), methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, polyacrylic acid, oxidized starch, phosphorylated starch, casein, and salts thereof, gum arabic, xanthan gum, alginic acid compound 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 still more preferably 0.8 to 3.0% by mass with respect to the entire nonvolatile components of the slurry.
[Slurry dispersion medium]
The slurry dispersion medium of the present invention is water. It may be pure water or ion exchange water. For 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 preventing agent (C) is not included in the dispersion medium. Examples of other dispersion media include alcohols such as methanol, ethanol, and isopropyl alcohol; ketones such as acetone. When using another dispersion medium, the content of water is preferably 80% by mass or more of the entire dispersion medium.

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

(Preparation method of slurry for non-aqueous battery electrode)
One embodiment of the method for preparing the slurry 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 further adding, dispersing, dissolving or kneading the active material (A) and additives used as necessary.
The anti-cracking agent (C), thickener (D) and other additives can be mixed in step (I) or in step (II).

As for other embodiment of the preparation method of the slurry of the present invention, the method including the following processes is mentioned, for example.
(I) A step of emulsion-polymerizing the one or more ethylenically unsaturated monomers to obtain an aqueous emulsion (EM) of the binder resin (B).
(II) A step of further adding and dispersing and dissolving the active material (A) and additives used as necessary to the aqueous emulsion (EM).
The anti-cracking agent (C), thickener (D) and other additives can be mixed after step (I) or in step (II).

(Nonaqueous battery electrode)
The nonaqueous battery electrode of one embodiment of the present invention (hereinafter, referred to as “electrode of this embodiment”).
) Has an electrode active material layer formed on the current collector from the slurry for non-aqueous battery electrodes of the present invention described above.
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 can be particularly effective when used as a negative electrode. In particular, when it is used as a negative electrode of a lithium ion non-aqueous battery electrode, the effect can be exhibited most.

The current collector in the electrode of this 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 not particularly limited, but it is usually preferable to use a sheet having a thickness of 0.001 to 0.5 mm.

The electrode of this embodiment has a current collector and an electrode active material layer formed on the current collector, and the electrode active material layer includes 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 a current collector using the slurry for non-aqueous battery electrodes of the present invention containing the negative electrode active material described above. The amount of nonvolatile components in the slurry on one side formed on the current collector (weight per unit area of the negative electrode active material layer) 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 preferable.
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 a current collector using the slurry for non-aqueous battery electrodes of the present invention containing the positive electrode active material described above. Nonvolatile component of the slurry of one side that is formed on the current collector (basis weight of the positive electrode active material layer) is preferably 10 ~ 40mg / cm ² on one side, more preferably ^{13 ~ 30mg / cm 2, 15} ~ 25mg / Cm ² is more preferable.

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. Moreover, the electrode of this embodiment can also make favorable the binding property of an electrode active material layer and a collector. In particular, by using the slurry for non-aqueous battery electrodes according to the present invention, it is possible to obtain an electrode that is hard to crack even when the slurry is applied thickly and the electrode active material layer is formed thick. Thereby, the high energy density of a non-aqueous battery can be achieved. Such an effect can be made extremely good particularly when copper is used as a current collector.

[Non-aqueous battery]
The non-aqueous battery of one embodiment of the present invention is a lithium ion non-aqueous battery (hereinafter may be referred to as “battery of this embodiment”). The battery according to this embodiment uses the non-aqueous battery electrode according to one embodiment of the present invention described above. That is, the electrode is made of a non-cracked electrode that is formed with a thick electrode active material layer using the non-aqueous battery electrode slurry of the present invention.
For example, the non-aqueous battery of this embodiment preferably includes 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 this embodiment can be manufactured according to a known method using a positive electrode and a negative electrode, an electrolytic solution, and parts such as a separator as necessary. As the electrode, the electrode of the present invention described above may be used for both the positive electrode and the negative electrode, and the electrode of the present embodiment described above may be used for one of the positive electrode and the negative electrode. When used, it is particularly effective.
As a battery exterior body, a metal exterior body or an aluminum laminate exterior body can be used. The shape of the battery may be any shape such as a coin shape, a button shape, a sheet shape, a cylindrical shape, a square shape, and a flat shape. Any known lithium salt may be used as the electrolyte in the battery electrolyte, and may be selected according to the type of 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 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 carboxylate lithium.

The solvent for dissolving the electrolyte is not particularly limited as long as it is usually used as a liquid for dissolving the electrolyte. Ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate ( Carbonate compounds such as DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC) and 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-methyltetrahydrofuran; sulfoxide compounds such as dimethyl sulfoxide; 1,3-dioxolane, 4-methyl-1,3-dioxo Oxolane compounds such as lanthanum; nitrogen-containing compounds such as acetonitrile, nitromethane, formamide, dimethylformamide; organic acid ester compounds such as methyl formate, methyl acetate, ethyl acetate, butyl acetate, methyl propionate, ethyl propionate; phosphoric acid triester Triglyme compounds; sulfolane compounds such as sulfolane and methylsulfolane; oxazolidinone compounds such as 3-methyl-2-oxazolidinone; sultone compounds such as 1,3-propane sultone, 1,4-butane sultone and naphtha sultone; It is done. These may be used individually by 1 type and may be used in combination of 2 or more type.
The non-aqueous battery of one embodiment of the present invention may be a lithium ion non-aqueous battery.

(Method for producing non-aqueous battery electrode)
The manufacturing method of the non-aqueous battery electrode of one embodiment of the present invention includes the following steps.
(III) The process of forming an electrode active material layer by apply | coating the slurry for non-aqueous battery electrodes obtained by said process (I) and (II) on a collector, and drying.
The electrode of this embodiment can be obtained by, for example, applying the above-described slurry for non-aqueous battery electrode of the present invention on a current collector and drying it.
As a coating method, general methods can be used, for example, reverse roll method, direct roll method, doctor blade method, knife method, extrusion method, curtain method, gravure method, bar method, dip method and squeeze method. I can give you. Among these, from the viewpoint that the surface state of the electrode active material layer can be improved by selecting a coating method according to various physical properties such as viscosity of the slurry of the present invention and drying properties, a doctor blade method, a knife method, Or the extrusion method is preferable. The drying temperature can be selected from 25 ° C. to 180 ° C. according to the 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.
Moreover, the electrode of this embodiment can be pressed as needed after formation of an electrode active material layer. As a pressing method, a general method can be used, but a mold pressing method and a calendar pressing method are particularly preferable. The pressing pressure is not particularly limited, but is preferably 0.2 to 3 t / cm ² .

EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated further in detail, this invention is not limited by these. In the examples and comparative examples, “parts” and “%” represent parts by mass and mass%, respectively, unless otherwise specified.
Moreover, the following measurement and evaluation were performed about the material used by the Example and the comparative example, the slurry for non-aqueous battery electrodes obtained by the Example and the comparative example, and the electrode for non-aqueous batteries. The results are shown in Table 2 or 3.

[Evaluation method]
(Nonvolatile content of water-based emulsion (EM) and nonvolatile content of slurry)
As an evaluation sample, 1 g of an aqueous emulsion (EM) or slurry was weighed on an aluminum dish having a diameter of 5 cm, dried at 105 ° C. for 1 hour in the air, and the residue was weighed.

(viscosity)
Using a Brookfield rotational viscometer, the liquid temperature was 23 ° C., the rotational speed was 60 rpm, 2 or No. Measurements were taken with 3 rotors.

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

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

(Slurry appearance)
Mix components described below to obtain a slurry for a non-aqueous battery electrode (negative electrode), and after 10 minutes, visually observe and separate the liquid, see sediment, and non-fluidity x, uniformly What was disperse | distributed was set as (circle).

(Electrode appearance)
The surface was visually observed after preparation of the electrode. The case where there was a crack was indicated as x, and the case where there was no crack was indicated as ◯.

(Electrode adhesion)
The prepared negative electrode was allowed to stand for 24 hours at 23 ° C. and 50% RH to obtain 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 using a double-sided tape, peeled at 180 ° (peel width 25 mm, peel rate 100 mm / min), and peel strength was measured. When the peel strength is small, the active material layer is likely to cohesively break, and the binding properties between the active materials and between the active material and the current collector are low.

[Synthesis example]
(Synthesis of binder resin B-1)
In a separable flask having a condenser, 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) (trade name, manufactured by Sanyo Chemical Industries, Ltd.) 0.11 parts by weight of non-reactive anionic emulsifier (Daiichi Kogyo Seiyaku Co., Ltd., trade name Haitenol 08E, polyoxyethylene alkyl ether sulfate ester salt) 02 parts by mass were charged, and liquid bubbling with nitrogen gas was performed 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 general formula (4), a non-reactive anionic emulsifier (Daiichi Kogyo Seiyaku Co., Ltd., trade name Haitenol 08E, polyoxyethylene alkyl ether) (Sulfate ester salt) 0.17 parts by mass, 49.2 parts by mass of styrene, 43.1 parts by mass of 2-ethylhexyl acrylate, 1.90 parts by mass of 2-hydroxyethyl methacrylate, 1.90 parts by mass of acrylic acid, parastyrene A monomer emulsion prepared by previously mixing 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, a solution obtained by dissolving 0.40 parts by mass of potassium persulfate as a polymerization initiator in 9.30 parts by mass of ion-exchanged water was dropped and 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 ratio of the binder resin B-1 in the aqueous emulsion (nonvolatile content) of 40% by mass, and the average particle diameter 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 monomers, 52.4 parts by mass of styrene, 40.6 parts by mass of 2-ethylhexyl acrylate, 3.80 parts by mass of acrylic acid, 1.90 parts by mass of itaconic acid, 0.60 parts by mass of sodium parastyrene sulfonate, divinyl An anionic aqueous emulsion EM2 in which the binder resin B-2 was dispersed was obtained in the same manner as in the aqueous emulsion EM1, except that 0.67 parts by mass of benzene was used. The obtained anionic aqueous emulsion EM2 has a nonvolatile content of 40% by mass, pH 7.0, 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 15 ° C. and the acid value was 40 mgKOH / g.

(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. 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 KK, particle size 12 μm, specific surface area 2.5 m ² / g), carbon black C-65 (manufactured by Timcal), thickener (D) After mixing 2% by weight aqueous solution of CMC (weight average molecular weight 3 million, substitution degree 0.9) and water in the ratio of Table 1 (step 1), emulsion EM1, crack inhibitor (C) as binder resin (B) NMP and water were mixed in the proportions shown in Table 1 (step 2) to obtain a slurry for a nonaqueous battery electrode (negative electrode) of Example 1. The evaluation results are shown in Table 2.

(Preparation of negative electrode)
On one side of a copper foil as a current collector, a slurry for a non-aqueous battery electrode (negative electrode) was applied so that the wet thickness was 280 μm, heated and dried at 60 ° C. for 2 minutes, and further dried at 100 ° C. for 2 minutes. .
Thereafter, 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)
A slurry for a non-aqueous battery electrode and a non-aqueous system were the same as in Example 1 except that the water-based emulsion (EM) was changed to the formulation 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 preventing agents used are as follows.
NMP: N-methylpyrrolidin-2-one (manufactured by Wako Pure Chemical Industries, Ltd.)
Butyl cellosolve: Ethylene glycol monobutyl ether (manufactured by Dow Chemical Japan Co., 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 (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 (Mitsubishi Chemical Corporation)
Benzyl alcohol: Benzyl alcohol (Arc Corporation)
Phenoxyethanol-SP: Phenoxyethanol (manufactured by Yokkaichi Chemical Co., Ltd.)
Wydinol EHP01: Propylene glycol-mono-2-ethylhexanoate (manufactured by Yokkaichi Chemical Co., Ltd.)
Texanol: 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoate (manufactured by Chisso Corporation)
Benzoflex 9-88: Dipropylene glycol dibenzoate (manufactured by Velsicol 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 those shown in Tables 2 and 3. Got. The evaluation results are shown in Tables 2 and 3.

As is apparent from the evaluation results of the non-aqueous battery electrode slurry shown in Tables 2 and 3 and the evaluation results of the non-aqueous battery electrode produced using the slurry, the implementation using the non-aqueous battery electrode slurry of the present invention was performed. In Examples 1 to 12, there were no cracks or the like in the electrode, and the adhesion to the electrode was high. Among them, Examples 1 to 4, 7, 11, and 12 using a crack preventing agent having a boiling point exceeding 200 ° C. were particularly excellent in electrode adhesion.

Claims (14)

1. A non-aqueous battery electrode active material (A);
   A binder resin (B);
   An anti-cracking agent (C);
   A slurry for a non-aqueous battery electrode containing water,
   The anti-cracking agent (C) has a boiling point at 1 atm of 120 ° C. or higher and a solubility in water at 20 ° C. of 10 g / 100 mL or higher.
2. The crack preventing agent (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, dimethyl sulfoxide The slurry for non-aqueous battery electrodes according to claim 1, wherein the slurry is at least one.
3. The slurry for non-aqueous battery electrodes according to claim 1, wherein the crack preventing agent (C) is an organic solvent having a boiling point of 150 ° C or higher at 1 atm.
4. The slurry for nonaqueous battery electrodes according to claim 1, wherein the crack preventing agent (C) is an organic solvent having a boiling point of more than 200 ° C at 1 atmosphere.
5. The slurry for nonaqueous battery electrodes according to any one of claims 1 to 4, comprising 10 to 500 parts by mass of the crack preventing agent (C) with respect to 100 parts by mass of the binder resin (B).
6. The slurry for nonaqueous battery electrodes according to any one of claims 1 to 5, further comprising a thickener (D).
7. The slurry for non-aqueous battery electrodes according to claim 6, wherein the thickener (D) is carboxymethylcellulose (CMC).
8. The binder resin (B) is a copolymer (P1) of a styrene monomer and a diene monomer, and a copolymer of a styrene monomer and an ethylenically unsaturated carboxylic acid ester monomer. The slurry for nonaqueous battery electrodes according to any one of claims 1 to 7, which is at least one selected from (P2).
9. The binder resin (B) includes a copolymer (P1) of a styrenic monomer and a diene monomer, and is a styrenic component among all ethylenically unsaturated monomer components constituting the copolymer. The slurry for non-aqueous battery electrodes according to any one of claims 1 to 8, wherein the monomer component is 5 to 70 mass% and the diene monomer component is 30 to 95 mass%.
10. The non-aqueous system according to any one of claims 1 to 9, wherein the binder resin (B) includes a copolymer (P2) of a styrene monomer and an ethylenically unsaturated carboxylic acid ester monomer. Slurry for battery electrodes.
11. The binder resin (B) according to any one of claims 1 to 10, wherein the binder resin (B) contains a copolymer of a styrene monomer, an ethylenically unsaturated carboxylic acid monomer, and an ethylenically unsaturated carboxylic acid monomer. The slurry for non-aqueous battery electrodes according to Item 1.
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 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 components forming the copolymer. Electrode slurry.
13. A method for producing a nonaqueous battery electrode, comprising a step of applying the slurry according to any one of claims 1 to 12 on a current collector and drying the slurry.
14. A method for producing a non-aqueous battery comprising the method for producing a non-aqueous battery electrode according to claim 13.