JP2020140957A - Dispersant composition for secondary battery slurry and utilization thereof - Google Patents

Abstract

To provide: a dispersant composition for a secondary battery slurry, which has good dispersion stability; a secondary battery slurry composition, which has good coatability and coating film dryability; a method for manufacturing the secondary battery slurry composition having good coatability and coating film dryability; and a battery arranged by using the secondary battery slurry composition.SOLUTION: A secondary battery slurry composition comprises a component (A) described below, and a component (B) described below, a rheology conditioner (C), and inorganic particles, and satisfies a certain requirement. The dispersant composition for a secondary battery slurry satisfies a certain requirement. Component (A) is a water-soluble polymer including 70 weight % or more of nitrogen atom-containing monomer units. Component (B) is a water-soluble polymer including 60-99 weight % of hydroxyl group-containing monomers and having a polymerization degree of 100-10000.SELECTED DRAWING: None

Description

The present invention relates to a dispersant composition for a secondary battery slurry and its use. More specifically, for a dispersant composition for a secondary battery slurry having good dispersion stability of the slurry, a dispersant composition for a secondary battery slurry having good coatability and dryness of a coating, heat resistance and electrodes, and a separator. The present invention relates to a secondary battery electrode having excellent binding properties, a coating for a separator, and a method for manufacturing the same.

In recent years, in electronic devices, secondary batteries such as lithium ion secondary batteries, nickel-hydrogen secondary batteries, and nickel-cadmium secondary batteries and capacitors such as electric double layer capacitors, which can be repeatedly used by charging, have been used. .. Secondary batteries are rapidly being developed as batteries for use in portable electronic devices and hybrid vehicles. For example, a lithium ion secondary battery is mainly composed of a positive electrode, a negative electrode, a separator, and a non-aqueous electrolyte solution, and various studies have been made to improve the battery characteristics.

For example, the positive electrode is manufactured by applying a positive electrode secondary battery slurry containing a positive electrode active material and a solvent to a current collector and drying the positive electrode. The negative electrode is manufactured by applying a negative electrode secondary battery slurry containing a negative electrode active material and a solvent to a current collector and drying the negative electrode. The separator is a material that can isolate the positive electrode and the negative electrode and improve the safety of the battery. For example, a porous film of polyolefin has excellent properties. For the purpose of improving the safety of the base material and the battery characteristics, a coating slurry containing organic particles and inorganic particles is further applied to the surfaces of the positive electrode, the negative electrode, and the separator base material, dried, and surface-coated. Negative electrodes and separators have also been developed. However, in a situation where a secondary battery having a larger capacity is required, a material for a secondary battery capable of further improving safety and battery characteristics has been demanded.

As a means for ensuring safety, for example, there is a method of providing a shutdown function for preventing further heat generation by blocking the passage of ions between the positive and negative electrodes by the above-mentioned separator in the event of abnormal heat generation. With the shutdown function, the separator melts and becomes non-porous when abnormal heat is generated, blocking the passage of ions and suppressing further heat generation. For example, a separator made of a porous film made of polyolefin suppresses further heat generation by blocking (shut down) the passage of ions by melting and non-porousing at about 80 to 180 ° C. when the battery generates abnormal heat. .. However, when the heat generation is intense, the separator made of the porous film may cause a short circuit due to direct contact between the positive electrode and the negative electrode due to shrinkage or film rupture. As described above, the separator made of a porous film made of polyolefin has insufficient shape stability and may not be able to suppress abnormal heat generation due to a short circuit.

For example, Patent Document 1 is formed by laminating a heat-resistant layer containing a fine particle filler and a porous film mainly composed of polyolefin as a base material (hereinafter, may be referred to as "base material porous film"). Separator for non-aqueous electrolyte secondary battery made of laminated porous film; Patent Document 2 uses a fine particle filler having a modified surface as a heat-resistant layer of the separator; Patent Document 3 features a chemical structure of a binder resin. A method of binding the holding filler and the like are disclosed.

On the other hand, as a method for improving the battery characteristics, as described above, heat shrinkage is suppressed by further coating and drying a coating slurry containing organic particles and inorganic particles on the positive electrode and the negative electrode, and the electrode active material is used. Measures may be taken to increase the adhesive strength.

For example, Patent Document 4 discloses a method for improving electrode characteristics by using a slurry for a secondary battery porous membrane containing non-conductive particles and a polycarboxylic acid.

However, these methods have the dispersibility of the inorganic powder in the coating slurry, the storage stability of the coating slurry, the film forming property of the coating slurry, the drying property of the coating film, the uniformity and heat resistance, and the binding with electrodes, separators and the like. It does not solve the problem of sexuality, and further improvement in performance is required.

Japanese Unexamined Patent Publication No. 2004-227972 JP-A-2007-31151 Japanese Unexamined Patent Publication No. 2006-331760 Japanese Unexamined Patent Publication No. 2015-162312

An object of the present invention is a dispersant composition for a secondary battery slurry having good dispersion stability, a secondary battery slurry composition having good coatability and film drying property, and good coating property and film drying property. It is an object of the present invention to provide a method for producing a secondary battery slurry composition and a battery using the secondary battery slurry composition.

As a result of diligent studies, the present inventors have found that a dispersant composition for a secondary battery slurry having a specific component and a specific condition can solve the problem of the present application, and have arrived at the present invention.
That is, the present invention is a dispersant composition containing the following component (A), the following component (B), and the rheology adjusting agent (C), which satisfies the following conditions 1 to 3 and is a dispersant for a secondary battery slurry. It is a composition.
Component (A): Water-soluble polymer component containing 70% by weight or more of nitrogen atom-containing monomer unit (B): 60 to 99% by weight of hydroxyl group-containing monomer unit, and the degree of polymerization is 100 to 10,000. Water-soluble polymer Condition 1: The elastic modulus of the molded film made of the non-volatile component of the dispersant composition after swelling of the electrolytic solution is 500 MPa or more.
Condition 2: The elastic modulus of the molded film composed of the non-volatile component composed of the component (A) and the component (B) is 500 MPa or more.
Condition 3: The glass transition point of the non-volatile component composed of the component (A) and the component (B) is 50 to 150 ° C.

It is preferable to further contain the surfactant (D).
The weight ratio (B / A) of the component (B) to the component (A) is 0.2 to 3.0, and the total content of the component (A) and the component (B) is 100 parts by weight. When the content of the rheology adjuster (C) is 0.5 to 200 parts by weight,
When the total content of the component (A), the component (B) and the rheology adjuster (C) is 100 parts by weight, the content of the surfactant (D) is 0.01 to 20 parts by weight. Is preferable.
The viscosity of the 4% by weight aqueous solution of the component (B) at 20 ° C. is preferably 1 to 500 mPa · s.
The rheology adjuster (C) is preferably carboxylmethyl cellulose having a degree of etherification of 0.55 to 1.1 and a viscosity of a 1% by weight aqueous solution of 1 to 100 mPa · s at 20 ° C.

The secondary battery slurry composition of the present invention is a secondary battery slurry composition containing the following component (A), the following component (B), a rheology adjuster (C) and inorganic particles, and contains the inorganic particles. When the amount is 100 parts by weight, the total of the component (A), the component (B) and the rheology adjusting agent (C) is 0.1 to 50 parts by weight, and the following conditions 1 to 3 are satisfied.
Component (A): Water-soluble polymer component containing 70% by weight or more of nitrogen atom-containing monomer unit (B): 60 to 99% by weight of hydroxyl group-containing monomer unit, and the degree of polymerization is 100 to 10,000. Water-soluble polymer condition 4: The elasticity of the molded film composed of the component (A), the component (B) and the rheology adjuster (C) after swelling of the electrolytic solution is 500 MPa or more.
Condition 5: The elastic modulus of the molded film composed of the non-volatile component composed of the component (A) and the component (B) is 500 MPa or more.
Condition 6: The glass transition point of the non-volatile component composed of the component (A) and the component (B) is 50 to 150 ° C.

The method for producing a material for a secondary battery of the present invention includes a step (a) of mixing the dispersant composition for a secondary battery slurry and a solvent to obtain a dispersant mixed solution, and the dispersant mixed solution and inorganic particles. The steps (b) of mixing the above-mentioned slurry composition to obtain a slurry composition and a step (c) of applying the slurry composition to at least one selected from a positive electrode, a negative electrode and a separator and drying the mixture to form a film are included.

The electrode for a secondary battery of the present invention is an electrode having a coating film on an electrode plate, and the coating film is formed of a non-volatile component of the secondary battery slurry composition.
The separator for a secondary battery of the present invention is a separator having a coating film for a separator, and the coating film is formed of a non-volatile component of the secondary battery slurry composition.
The secondary battery of the present invention is a secondary battery containing a positive electrode, a negative electrode, a separator and an electrolytic solution, and at least one selected from the positive electrode, the negative electrode and the separator is a non-volatile component of the secondary battery slurry composition. It has a coating formed by.

The slurry containing the dispersant composition for the secondary battery slurry of the present invention has good dispersion stability.
The secondary battery slurry of the present invention is excellent in coatability and film drying property.
The electrode and separator coatings produced using the secondary battery slurry composition of the present invention are excellent in heat resistance and binding properties.

The dispersant composition for a secondary battery slurry of the present invention essentially contains a component (A), a component (B) and a rheology adjuster (C). Each component will be described in detail.

[Component (A)]
The component (A) is a water-soluble polymer component containing 70% by weight or more of nitrogen atom-containing monomer units.
Examples of the nitrogen atom-containing monomer unit include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethoxyacrylonitrile, fumaronitrile, acrylamide, methacrylamide, methylenebisacrylamide, N-methylolacrylamide, isopropylacrylamide, diethylacrylamide and the like. Can be mentioned. Among these, acrylamide, methacrylamide, methylenebisacrylamide, N-methylolacrylamide, isopropylacrylamide, and diethylacrylamide are particularly preferable from the viewpoint of exerting the effects of the present application.

The component (A) contains 70% by weight or more of a nitrogen atom-containing monomer unit, preferably 80% by weight or more, more preferably 90% by weight or more, still more preferably 95% by weight or more. If it is less than 70% by weight, the dispersibility is insufficient, and the heat resistance is insufficient due to a decrease in the elastic modulus of the coating film. The preferable upper limit value of the component (A) is 100% by weight.

Regarding the solubility of the component (A) in water, it is water-soluble because it has excellent dispersibility. The term "water-soluble" in the present application means that 1 g or more is dissolved in 100 g of water at 25 ° C.
The viscosity of the 20% aqueous solution of the component (A) at 25 ° C. is not particularly limited, but is preferably 2000 to 20000 mPa · s, and more preferably 5000 to 19000 mPa · s, from the viewpoint of dispersion stability and coatability. It is preferably 1000 to 18000 mPa · s, more preferably 11000 to 17000 mPa · s, and most preferably 12000 to 16000 mPa · s. If it is less than 2000 mPa · s, the dispersion stability may deteriorate. If it exceeds 20000 mPa · s, the coatability may deteriorate. The method for measuring the viscosity of the 20% aqueous solution of the component (A) at 25 ° C. is the method described in Examples.

The weight average molecular weight of the component (A) is not particularly limited, but is usually 100,000 or more and less than 3 million, preferably 150,000 or more and less than 2 million, and particularly preferably 200,000 or more and less than 1 million. If the weight average molecular weight of the component (A) is less than 100,000, the binding property may not be excellent. On the other hand, if the weight average molecular weight of the component (A) is 3 million or more, the handleability may not be excellent.

The weight loss of 300 ° C. by thermogravimetric measurement of component (A) (TGA, introducing dry air as a purge gas, and heating at a temperature rise of 10 ° C./min from 40 ° C.) is not particularly limited, but is preferably 50 weight. %, More preferably less than 40% by weight, even more preferably less than 30% by weight, particularly preferably less than 20% by weight, most preferably less than 10% by weight. If it exceeds 50% by weight, the heat resistance may not be sufficient.

[Component (B)]
The component (B) is a water-soluble polymer component containing 60 to 99% by weight of a hydroxy group-containing monomer unit and having a degree of polymerization of 100 to 10,000. Examples of the hydroxy group-containing monomer unit include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, vinyl alcohol, and the like, and may be one or more. Among these, vinyl alcohol is particularly preferable from the viewpoint of exhibiting the effects of the present application. In the following, acrylate or methacrylate may be collectively referred to as (meth) acrylate, and (meth) acrylate means acrylate or methacrylate.

The monomer unit of vinyl alcohol may be obtained by hydrolyzing polyvinyl acetate obtained by polymerizing vinyl acetate.
The component (B) contains 60 to 99% by weight of the hydroxy group-containing monomer unit, preferably 75 to 99% by weight, more preferably 80 to 99% by weight, and particularly preferably 87 to 99% by weight. If it is less than 60% by weight, the dispersibility is insufficient. If it exceeds 99% by weight, the coatability is insufficient.

Examples of the component (B) of the present invention include Kuraray Poval series (polyvinyl alcohol, Kuraray Co., Ltd.), Denka Poval series (polyvinyl alcohol, Denka Co., Ltd.), and J-POVAL series (polyvinyl alcohol, Japan Vam & Poval stock). A commercially available water-soluble polymer such as Cerball series (polyvinyl alcohol, Sekisui Chemical Co., Ltd.) may be used.

Regarding the solubility of the component (B) in water, it is water-soluble because it has excellent dispersibility.
The viscosity of the 4% by weight aqueous solution of the component (B) at 20 ° C. is not particularly limited, but is preferably 1 to 500 mPa · s, more preferably 2 to 300 mPa · s, from the viewpoint of dispersion stability and coatability. It is preferably 3 to 100 mPa · s, more preferably 4 to 50 mPa · s, and most preferably 5 to 30 mPa · s. If it is less than 1 mPa · s, the dispersion stability may deteriorate. If it exceeds 500 mPa · s, the coatability may deteriorate. The method for measuring the viscosity of the 4% by weight aqueous solution of the component (B) at 20 ° C. is as described in Examples.

The weight average molecular weight of the component (B) is not particularly limited, but is usually 10,000 or more and less than 1.5 million, preferably 10,000 or more and less than 1 million, and more preferably 15,000 or more and less than 500,000. More preferably, it is 20,000 or more and less than 250,000, and particularly preferably 30,000 or more and less than 150,000. If the weight average molecular weight of the component (B) is less than 10,000, the binding property may not be excellent. On the other hand, if the weight average molecular weight of the component (B) is 1.5 million or more, the handleability may not be excellent.

The degree of polymerization of the component (B) is 100 or more and 10000 or less, preferably 200 or more and less than 5000, more preferably 300 or more and less than 3000, still more preferably 400 or more and less than 2000, and particularly preferably 1000 or more and less than 2000. If the degree of polymerization of the component (B) is less than 100, the elastic modulus of the dry film is lowered and the binding property is not excellent. On the other hand, when the degree of polymerization of the component (B) is 10,000 or more, the handleability is not excellent.

The weight loss of 300 ° C. by thermogravimetric measurement of component (B) (TGA, introducing dry air as a purge gas, and heating at a temperature rise of 10 ° C./min from 40 ° C.) is not particularly limited, but is preferably 50 weight. %, More preferably less than 40% by weight, even more preferably less than 30% by weight, particularly preferably less than 20% by weight, most preferably less than 10% by weight. If the weight loss of the component (B) at 300 ° C. by thermogravimetric analysis exceeds 50% by weight, the heat resistance may not be sufficient.

The component (A) and the component (B) may contain other monomer units. The other monomer units are not particularly limited, but are, for example, styrene-based monomer units such as styrene, α-methylstyrene, and chlorostyrene; glycidyl (meth) acrylate, hydroxymethylacrylate glycidyl ether, and 2-hydroxy. A glycidyl group-containing monomer unit such as ethyl acrylate glycidyl ether, 3-hydroxypropyl acrylate glycidyl ether, 4-hydroxybutyl acrylate glycidyl ether, glycidyl vinyl ether, glycidyl allyl ether, diglycidyl ether, epichlorohydrin, glycidyl trimethylammonium chloride, etc. Maleimide-based monomer units such as N-phenyl maleimide, N- (2-chlorophenyl) maleimide, N-cyclohexyl maleimide, N-lauryl maleimide; achlorine; vinyl trichlorosilane, vinyl trimethoxysilane, vinyl triethoxysilane, vinyl Unsaturated organic silanes such as triisopropoxysilane; vinyl halide monomer units such as vinyl chloride, vinylidene chloride and vinyl bromide and vinylidene halide monomer units; vinyl acetate, vinyl propionate, vinyl neodecanoate Examples thereof include vinyl ester-based monomer units such as esters, and one or more of them may be used.

The component (A) and the component (B) are a polymer composed of a polymerizable monomer unit and a polymerizable monomer unit having two or more polymerizable double bonds (crosslinking agent monomer unit). It may be. The cross-linking agent monomer unit is not particularly limited, but is, for example, an aromatic divinyl compound such as divinylbenzene or divinylnaphthalene; ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,9-nonanediol. (Meta) acrylate compounds such as di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol tetra (meth) acrylate; 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, dicyclohexylcarbodiimide, poly Examples thereof include carbodiimide compounds such as carbodiimide; polyfunctional epoxy compounds; oxazoline compounds; polyfunctional hydrazide compounds; isocyanate compounds; melanin compounds; urea compounds, and one or more of them may be used in combination.

The glass transition point Tg (° C.) of the component (A) is not particularly limited, but is preferably 50 to 250 (° C.), more preferably 80 to 200 ° C., further preferably 100 to 180 ° C., and 110 to 160 ° C. Is particularly preferable. Below 50 ° C, the dispersibility may be insufficient, and above 250 ° C, the film forming property may be insufficient.

The glass transition point Tg (° C.) of the component (B) is not particularly limited, but is preferably 0 to 250 (° C.), more preferably 10 to 200 ° C., further preferably 25 to 180 ° C., and 50 to 150 ° C. Is particularly preferable. Below 50 ° C, the dispersibility may be insufficient, and above 250 ° C, the film forming property may be insufficient.

The dispersant composition for a secondary battery slurry of the present invention satisfies the following condition 3.
Condition 3: The glass transition point of the non-volatile component composed of the component (A) and the component (B) is 50 to 150 ° C.
When the non-volatile component composed of the component (A) and the component (B) has a glass transition point in this range, it is possible to secure the heat resistance and the binding property of the entire coating film. The glass transition point of the mixture is more preferably 70 to 140 ° C, particularly preferably 100 to 140 ° C. Below 50 ° C, the heat resistance of the coating film decreases, and above 150 ° C, the binding property becomes insufficient. The method for measuring the glass transition point of the non-volatile component composed of the component (A) and the component (B) is the method described in Examples.

The dispersant composition for a secondary battery slurry of the present invention satisfies the following condition 2.
Condition 2: The elastic modulus of the molded film composed of the non-volatile component composed of the component (A) and the component (B) is 500 MPa or more.
By setting the elastic modulus of the molded film composed of the non-volatile component composed of the component (A) and the component (B) within this range, it is possible to secure the heat resistance and the binding property of the entire film. The elastic modulus of the molded film made of the non-volatile component of the mixture is more preferably 800 MPa or more, further preferably 1000 MPa or more, and particularly preferably 1500 MPa or more. If it is less than 500 MPa, heat resistance and binding property are insufficient. The upper limit of the preferable elastic modulus is 10,000 MPa. The method for measuring the elastic modulus of a molded film composed of a non-volatile component composed of the component (A) and the component (B) is the method described in Examples.

The degree of swelling SW (A) (times) with respect to the electrolytic solution (1: 1 mixture of ethylene carbonate and dimethyl carbonate) of the component (A) is not particularly limited, but is preferably 1 to 5 times or more. It is more preferably 1 time or more and less than 4 times, further preferably 1.1 times or more and less than 3 times, further preferably 1.1 times or more and less than 2 times, and particularly preferably 1.1 times or more and less than 1.5 times. If the swelling degree SW (A) of the component (A) with respect to the electrolytic solution is less than 1, the battery characteristics may not be good. On the other hand, if the swelling degree SW (A) of the component (A) with respect to the electrolytic solution is 5 times or more, the heat resistance and binding property of the coating film may be insufficient.

The degree of swelling SW (B) (times) of the component (B) with respect to the electrolytic solution is not particularly limited, but is, for example, 1 to 5 times, preferably 1 to 4 times, more preferably 1.1. It is fold or more and less than 3 times, more preferably 1.1 times or more and less than 2 times, and particularly preferably 1.1 times or more and less than 1.5 times. If the swelling degree SW (B) of the component (B) with respect to the electrolytic solution is less than 1, the battery characteristics may not be good. On the other hand, if the swelling degree SW (B) of the component (B) with respect to the electrolytic solution is 5 times or more, the heat resistance and binding property of the coating film may be insufficient.

The weight ratio (B / A) of the component (B) to the component (A) is not particularly limited, but is preferably 0.2 to 3.0 from the viewpoint of binding property and heat resistance, and is preferably 0.3. It is more preferably ~ 2.3, and particularly preferably 0.4 to 1.5. If it is less than 0.2, the binding property may deteriorate. If it exceeds 3.0, both the binding property and the heat resistance may decrease due to the deterioration of the dispersion stability.

[Rheology adjuster (C)]
The dispersant composition of the present invention essentially contains the rheology modifier (C). The rheology adjuster (C) is used for the purpose of improving dispersion stability and coatability. The rheology modifier is appropriately selected and is not particularly limited, but for example, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, polyacrylic acid, polyethylene glycol, polyethylene oxide, polyoxyethylene / polypropylene block polymer, polyvinyl alcohol, polyvinyl pyrrolidone, Arabia. Water-soluble polymers such as gum, guar gum, xanthan gum, gelatin, corn starch, polyacrylamide; fiber-based polymers such as cellulose nanofibers, chitin nanofibers, polyolefin cotton-like fibers; aluminum magnesium silicate, basic magnesium sulfate inorganic fibers, etc. Examples include inorganic thickeners.

Among them, it is preferable that the rheology adjuster (C) is carboxymethyl cellulose because it has excellent dispersibility. The degree of etherification of carboxymethyl cellulose is not particularly limited from the viewpoint of excellent dispersibility, but is usually 0.55 to 1.1, preferably 0.6 to 1, and more preferably 0.65 to 0.9. It is particularly preferably 0.65 to 0.8, and most preferably 0.7 to 0.75.
The viscosity of a 1 wt% aqueous solution of carboxymethyl cellulose at 20 ° C. is not particularly limited, but is usually 1 to 100 mPa · s, preferably 3 to 50 mP · s, more preferably 5 to 20 mP · s, and particularly preferably 6. It is ~ 15 mP · s, most preferably 7 ~ 13 mP · s.

The content of the rheology adjuster (C) is not particularly limited, but is usually 0.5 to 200 parts by weight, preferably 0.5 to 200 parts by weight, when the total content of the component (A) and the component (B) is 100 parts by weight. Is 10 to 200 parts by weight, more preferably 25 to 150 parts by weight, particularly preferably 40 to 100 parts by weight, and most preferably 50 to 70 parts by weight. If the content of the rheology adjuster (C) is less than 0.5 parts by weight, the dispersibility and coatability may not be sufficient. On the other hand, if the content of the rheology adjuster is more than 200 parts by weight, the handleability may not be excellent.

[Surfactant (D)]
The dispersant composition of the present invention may further contain a surfactant (D) (hereinafter, may be simply referred to as a component (D)). The component (D) has a function of improving the dispersion stability and coatability of the slurry.
Examples of the component (D) include anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.

Examples of the anionic surfactant include fatty acid salts such as sodium oleate, potassium palmitate, and triethanolamine oleate; alkyl sulfates such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium stearyl sulfate, and sodium cetyl sulfate; Polyoxyalkylene alkyl ether acetate such as polyoxyethylene tridecyl ether sodium acetate; alkylbenzene sulfonate such as sodium dodecylbenzene sulfonate; polyoxyalkylene alkyl ether sulfate; stearoylmethyl taurine Na, lauroylmethyl taurine Na, myristylmethyl Higher fatty acid amide sulfonates such as taurine Na and palmitoylmethyl taurine Na; N-acylsarcosin salts such as sodium lauroyl sarcosin; alkyl phosphates such as sodium monostearyl phosphate; sodium polyoxyethylene oleyl ether phosphate, polyoxy Polyoxyalkylene alkyl ether phosphate salts such as ethylene stearyl ether sodium phosphate; long-chain sulfosuccinates such as sodium di-2-ethylhexyl sulfosuccinate, sodium dioctyl sulfosuccinate, sodium monosodium N-lauroyl glutamate, N-stearoyl Long-chain N-acylglutamates such as -L-disodium glutamate; polyacrylic acid, polymethacrylic acid, polymaleic acid, polyan anhydride, copolymers of maleic acid and isobutylene, and maleic anhydride and isobutylene. Copolymers, copolymers of maleic acid and diisobutylene, copolymers of maleic anhydride and diisobutylene, copolymers of acrylic acid and itaconic acid, copolymers of methacrylic acid and itaconic acid, Copolymers of maleic acid and styrene, copolymers of maleic anhydride and styrene, copolymers of acrylic acid and methacrylic acid, copolymers of acrylic acid and acrylic acid methyl ester, acrylic acid and acetic acid Alkali metal salts (lithium salt, sodium salt, potassium salt, etc.) of copolymers with vinyl, copolymers of acrylic acid and maleic acid, copolymers of acrylic acid and maleic anhydride, alkaline earth metal salts Polycarboxylic acid salts such as (magnesium salt, calcium salt, etc.), ammonium salt and amine salt; formalin condensate of naphthalene sulfonic acid, alkyl naphthalene sulfonic acid, naphthalene sulfonic acid, alkyl naphthalene sulfonate. Formalin condensates of acids and naphthalene sulfonates such as alkali metal salts (lithium salt, sodium salt, potassium salt, etc.), alkaline earth metal salts (magnesium salt, calcium salt, etc.), ammonium salts, amine salts, etc. Melamine sulfonic acid, alkyl melamine sulfonic acid, formalin condensate of melamine sulfonic acid, formalin condensate of alkyl melamine sulfonic acid, and alkali metal salts (lithium salt, sodium salt, potassium salt, etc.) and alkaline earth metals. Salts (magnesium salts, calcium salts, etc.), melamine sulfonates such as ammonium salts and amine salts; lignin sulfonic acid, and alkali metal salts (lithium salt, sodium salt, potassium salt, etc.), alkaline earth metals Examples thereof include salts (magnesium salts, calcium salts, etc.), lignin sulfonates such as ammonium salts and amine salts, and one or more of them may be used in combination.

Examples of the cationic surfactant include alkyltrimethylammonium salts such as stearyltrimethylammonium chloride, lauryltrimethylammonium chloride and cetyltrimethylammonium bromide; dialkyldimethylammonium salts; trialkylmethylammonium salts and alkylamine salts. 1 type or 2 or more types may be used in combination.

Examples of the nonionic surfactant include POE (30) lauryl ether, POE (12) lauryl ether, POE (9) myristyl ether, POE (3) lauryl ether, POP (2) POE (8) stearyl ether, and the like. Polyoxyalkylene oxide-added alkyl ethers such as POE (50) oleyl ether; polyoxyalkylene styrene phenyl ethers such as polyoxyethylene (24) styrene phenyl ethers; polyhydric alcohols such as sorbitan monopalmitate and sorbitan monooleate. Estre compound of and monovalent fatty acid; polyoxyalkylene alkylphenyl ether such as polyoxyethylene nonylphenyl ether and polyoxyethylene octylphenyl ether; polyoxyalkylene fatty acid such as polyoxyethylene monolaurate and polyoxyethylene monooleate. Esters; Polyoxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate; Glycerin fatty acid esters such as glycerin monostearate, glycerin monopalmitate and glycerin monolaurate; Polyoxyalkylene hardened castor oil; polyoxyalkylene sorbitol fatty acid ester; polyglycerin fatty acid ester; alkyl glycerin ether; polyoxyalkylene cholesteryl ether; alkyl polyglucoside; sucrose fatty acid ester; polyoxyalkylene alkyl amine; polyoxyethylene-polyoxy Examples include propylene block polymers.
The POE indicates polyoxyethylene, the POP indicates polyoxypropylene, and POE (12) indicates the addition of 12 mol of polyoxyethylene.

Examples of the amphoteric surfactant include 2-undecyl-N, N- (hydroxyethylcarboxymethyl) -2-imidazoline sodium, 2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt and the like. Imidazoline-based amphoteric surfactants; 2-heptadecyl-N-carboxymethyl-N-hydroxyethyl imidazolium betaine, lauryldimethylaminoacetic acid betaine, alkyl betaine, amide betaine, sulfobetaine and other betaine-based amphoteric surfactants; N- Examples thereof include amino acid-type amphoteric surfactants such as laurylglycine, N-lauryl β-alanine, and N-stearyl β-alanine, and one or more of them may be used in combination.

The content of the component (D) is not particularly limited, but is usually 0.01 to 0.01 when the total content of the component (A), the component (B) and the rheology adjuster (C) is 100 parts by weight. It is 20 parts by weight, preferably 0.05 to 15 parts by weight, more preferably 0.1 to 10 parts by weight, particularly preferably 0.5 to 8 parts by weight, and most preferably 1 to 5 parts by weight. If the content of the component (D) is less than 0.01 parts by weight, the dispersibility and coatability are not sufficient. On the other hand, when the content of the component (D) is more than 20 parts by weight, the binding property and the heat resistance are lowered due to the plasticization of the polymer.

[Defoamer component (E)]
When the dispersant composition for a secondary battery slurry of the present invention contains a defoaming agent component (E) (hereinafter, may be simply referred to as a component (E)), from the viewpoint of improving the handleability and coatability of the slurry. Therefore, it is preferable.
The component (E) is not particularly limited, but for example, a fat-based defoamer such as castor oil, sesame oil, flaxseed oil, and animal and vegetable oil; a fatty acid-based defoamer such as stearic acid, oleic acid, and palmitic acid; Fatty acid ester defoamers such as isoamyl acid, distealyl succinate, ethylene glycol distearate, butyl stearate; polyoxyalkylene monohydric alcohol, di-t-amylphenoxyethanol, 3-heptanol, 2-ethylhexanol, etc. Alcohol-based defoamers; ether-based defoamers such as 3-heptyl cellosolve, nonyl cellosolve, 3-heptyl carbitol, polyalkylene glycol; phosphate ester-based defoamers such as tributyl phosphate and tris (butoxyethyl) phosphate. Amine-based defoamers such as diamilamine; Amid-based defoamers such as polyalkyleneamide and acylate polyamine; Sulfate-based defoamers such as sodium lauryl sulfate; Polysiloxane-based defoamers such as dimethylpolysiloxane; Paraffin-based mineral oil, cyclopentene, cyclohexane, phichterite, mineral oil such as naphthen-based mineral oil such as oleanan; silica fine powder-based defoamer and the like may be mentioned, and one or more of them may be used in combination. Among them, it is preferable that the defoaming agent is at least one selected from a polysiloxane-based defoaming agent and silica fine powder because it is excellent in defoaming property.

The content of the component (E) is not particularly limited, but is usually 0.0001 to 0.0001 when the total content of the component (A), the component (B) and the rheology adjuster (C) is 100 parts by weight. 10 parts by weight, preferably 0.0005 to 1 part by weight, more preferably 0.001 to 0.5 parts by weight, particularly preferably 0.005 to 0.1 parts by weight, most preferably 0.01 to 0.05 parts. It is a part by weight. If the content of the component (E) is less than 0.0001 parts by weight, the defoaming property may not be sufficient. On the other hand, if the content of the component (E) is more than 10 parts by weight, the coatability may not be excellent.

[Other ingredients]
The dispersant composition for a secondary battery slurry of the present invention may contain other components other than the components described above. The other components are not particularly limited, and examples thereof include dispersion aids and pH adjuster components.

The dispersion aid used in the present invention has the effect of assisting the dispersion of the slurry and enhancing the stability of the slurry. The dispersion aid is not particularly limited, but for example, ketone compounds such as acetone, acetylacetone, dipivaloylmethane, dehydroacetic acid, diethyl malonate; methanol, ethanol, isopropyl alcohol, butanol, 3-methoxy-3-3. Alcohol compounds such as methyl-1-butanol; organic acids such as lactic acid, acetic acid, propionic acid, maleic acid, oxalic acid, formic acid, methanesulfonic acid, toluenesulfonic acid, citric acid, tartaric acid, ethylenediaminetetraacetic acid; hydrogen chloride, sulfuric acid , Inorganic acids such as acetic acid and phosphoric acid, and may be used alone or in combination of two or more. Among them, it is preferable that the dispersion aid is at least one selected from inorganic acids and organic acids because it is excellent in dispersion stability.

The molecular weight of the dispersion aid is not particularly limited, but is usually 10 to 2000, preferably 20 to 1000, more preferably 30 to 500, particularly preferably 40 to 300, and most preferably 50 to 200. If the molecular weight of the dispersion aid is less than 10, the dispersion stability may not be sufficient. On the other hand, if the molecular weight of the dispersion aid is more than 2000, the dispersibility may not be sufficient.

The content of the dispersion aid is not particularly limited, but is usually 0.01 to 10 when the total content of the component (A), the component (B) and the rheology adjuster (C) is 100 parts by weight. It is by weight, preferably 0.05 to 5 parts by weight, more preferably 0.1 to 4 parts by weight, particularly preferably 0.5 to 3 parts by weight, and most preferably 1 to 2 parts by weight. If the content of the dispersion aid is less than 0.01 parts by weight, the dispersion stability may not be sufficient. On the other hand, if the content of the dispersion aid is more than 10 parts by weight, the coatability may not be excellent.

The pH adjuster used in the present invention may be included for the purpose of enhancing dispersion stability. The pH adjuster is not particularly limited, but for example, alkaline (earth) metals such as sodium hydroxide, potassium hydroxide, cesium hydroxide, calcium hydroxide, barium hydroxide, strontium hydroxide, and magnesium hydroxide. Hydroxide; Ammonia; Carbonate such as sodium carbonate and sodium hydrogen carbonate; Metal oxidation of calcium oxide, sodium oxide, potassium oxide, magnesium oxide, barium oxide, silver oxide, chromium oxide, manganese oxide, iron oxide, bismuth oxide, etc. Substances; Amin compounds such as methylamine, dimethylamine, trimethylamine, ethylamine, ethylenediamine, monoethanolamine, spermin, aniline, toluidine, pyrrolidine, morpholine, imidazole, amino acids, etc. may be mentioned, and one or more of them may be used in combination. May be good. Among them, it is preferable that the pH adjuster is at least one selected from alkali (earth) metal hydroxides because it is excellent in versatility. Here, the alkaline (earth) metal means an alkali metal or an alkaline earth metal.

The molecular weight of the pH adjuster is not particularly limited, but is usually 10 to 2000, preferably 15 to 1000, more preferably 20 to 500, particularly preferably 25 to 200, and most preferably 30 to 100. If the molecular weight of the pH adjuster is less than 10, the dispersion stability may not be sufficient. On the other hand, if the molecular weight of the pH adjuster is more than 2000, the handleability may not be sufficient.

The content of the pH adjuster is not particularly limited, but is usually 0.01 to 10 when the total content of the component (A), the component (B) and the rheology adjuster (C) is 100 parts by weight. It is by weight, preferably 0.05 to 5 parts by weight, more preferably 0.1 to 4 parts by weight, particularly preferably 0.5 to 3 parts by weight, and most preferably 1 to 2 parts by weight. If the content of the pH regulator is less than 0.01 parts by weight, the dispersion stability may not be sufficient. On the other hand, if the content of the pH adjuster is more than 10 parts by weight, the coatability may not be excellent.

[Dispersant composition for secondary battery slurry, its production method and form]
The method for producing the dispersant composition for the secondary battery slurry is not particularly limited, and examples thereof include a method of mixing each component.

The mixing is not particularly limited, and can be performed by using a device equipped with an extremely simple mechanism such as a container and a stirring blade. The stirring blade is not particularly limited, and examples thereof include a max blend blade, a tornado blade, and a full zone blade. Further, a mixer capable of general shaking or stirring may be used. Examples of the mixer include a ribbon type mixer and a vertical screw type mixer. A mixer can be mentioned. In addition, Super Mixer (manufactured by Kawata Co., Ltd.), High Speed Mixer (manufactured by Fukae Co., Ltd.), Newgram Machine (manufactured by Seishin Enterprise Co., Ltd.), SV, which are efficient and multifunctional mixers by combining a stirrer. Mixer (manufactured by Kobelco Eco-Solutions Co., Ltd.), Philmix (manufactured by Primix Corporation), Jet Paceta (manufactured by Nihon Spindle Manufacturing Co., Ltd.), KRC Kneader (manufactured by Kurimoto Iron Works Co., Ltd.) , Photochemical Co., Ltd.) and the like may be used. Other crushers such as jaw crusher, gyre crusher, cone crusher, roll crusher, impact crusher, hammer crusher, rod mill, ball mill, vibrating rod mill, vibrating ball mill, disc mill, jet mill, cyclone mill, etc. You may use it. Further, an ultrasonic emulsifier, a continuous twin-screw kneader, a high-pressure emulsifier, a microreactor, or the like may be used.

The dispersant composition for a secondary battery slurry of the present invention satisfies the following condition 1.
Condition 1: The elastic modulus of the molded film made of the non-volatile component of the dispersant composition for the secondary battery slurry after swelling of the electrolytic solution is 500 MPa or more.
By setting the elastic modulus after swelling of the electrolytic solution of the molded film composed of the non-volatile component of the dispersant composition for the secondary battery slurry within this range, the heat resistance and binding property of the formed film in the battery can be ensured. it can. The elastic modulus is more preferably 800 MPa or more, further preferably 1000 MPa or more, and particularly preferably 1500 MPa or more. If it is less than 500 MPa, heat resistance and binding property are insufficient. The upper limit of the preferable elastic modulus is 10,000 MPa.
The "nonvolatile content of the dispersant composition for the secondary battery slurry" is a residue when heated at 110 ° C. and the weight becomes constant.

In the dispersant composition for a secondary battery slurry, the components (A) and (B) are effective for ensuring heat resistance and binding property while satisfying the above range of elastic modulus after swelling of the electrolytic solution. It is essential to adjust the glass transition point and elastic modulus when the components are mixed to the required range. Further, it is necessary to adjust the elastic modulus of the mixture of the component (A) and the component (B) within a predetermined range so as not to impair the heat resistance and the binding property obtained by adjusting the component (A) and the component (B). Is.
Further, by essentially containing the component (A) and the component (B) and satisfying the above conditions 1 to 3, the interaction between the component (A) and the component (B) can be improved, whereby the dispersant It is considered that the dispersion stability of the composition becomes excellent.

The surface tension of the dispersant composition for secondary battery slurry at 25 ° C. of an aqueous solution having a non-volatile content concentration of 0.1% by weight is not particularly limited, but is preferably 20 to 50 mN / m, more preferably 25 to 45 mN / m. m, particularly preferably 25 to 40 mN / m, most preferably 25 to 35 mN / m. If it is less than 20 mN / m, the drying property may not be excellent. If it exceeds 50 mN / m, the coatability may be poor.

In the dispersant composition for secondary battery slurry, as described in detail in the following examples, an aqueous dispersion having a non-volatile content concentration of 0.1% by weight of the dispersant composition for secondary battery slurry at a temperature of 25 ° C. The foaming force is measured by the Rosmiles test method under the measurement conditions, and the foaming force immediately after the flow of the dispersant composition for the secondary battery slurry is 200 mm or less, preferably 180 mm or less, more preferably 150 mm or less, and further. It is preferably 120 mm or less, and particularly preferably 100 mm or less. The foaming force 5 minutes after the flow is 100 mm or less, preferably 80 mm or less, more preferably 50 mm or less, still more preferably 30 mm or less, and particularly preferably 20 mm or less. If the foaming force immediately after flowing down is more than 200 mm according to the Rosmiles test method, the coatability of the secondary battery slurry is not sufficient. Further, if the foaming force 5 minutes after the flow is more than 100 mm, the coatability of the secondary battery slurry is not sufficient.

The zeta potential of the dispersant composition for the secondary battery slurry at the measurement temperature of 25 ° C. is not particularly limited, but is preferably -20 to -100 mV, more preferably 25 to -80 mV, and particularly preferably -30 to −. It is 70 mV, most preferably 35 to -60 mV. If it is less than -100 mV, the handleability may be poor. Above -20 mV, the dispersibility may not be excellent.

The pH of the aqueous dispersion having a non-volatile content concentration of 10% by weight of the dispersant composition for the secondary battery slurry is not particularly limited, but is preferably 4.0 to 12.0, more preferably 5.0 to 11. It is 0, particularly preferably 6.0 to 10.0, and most preferably 7.0 to 9.0. If the pH is less than 4.0, the coatability may be poor. If it exceeds 12.0, the handleability may be poor. The pH of the aqueous dispersion having a non-volatile content concentration of 10% by weight of the dispersant composition for the secondary battery slurry is measured by the method of the examples.

The contact angle after 1600 msec after dropping the droplet of the aqueous dispersion having a non-volatile content concentration of 1.0% by weight on the surface of the polypropylene resin of the dispersant composition for the secondary battery slurry is not particularly limited, but is preferable. It is 10 to 60 °, more preferably 15 to 60 °, particularly preferably 20 to 50 °, and most preferably 20 to 30 °. If it is less than 10 °, the dispersibility may not be excellent. If it exceeds 60 °, the coatability may be poor. The method for measuring the contact angle of the dispersant composition for a secondary battery slurry with a non-volatile content concentration of 1.0% by weight with respect to the polypropylene resin surface is the method described in Examples.

The contact angle after 1600 msec after dropping the droplet of the aqueous dispersion having a non-volatile content concentration of 1.0% by weight on the surface of the alumina plate of the dispersant composition for the secondary battery slurry is not particularly limited, but is preferable. It is 10 to 60 °, more preferably 15 to 60 °, and particularly preferably 20 to 50 °. If it is less than 10 °, the dispersibility may not be excellent. If it exceeds 60 °, the coatability may be poor. The method for measuring the contact angle of the dispersant composition for a secondary battery slurry with a non-volatile content concentration of 1.0% by weight with respect to the surface of the alumina plate is the method described in Examples.

The non-volatile content concentration of the dispersant composition for the secondary battery slurry is not particularly limited, but is usually 1 to 90% by weight, preferably 3 to 80% by weight, more preferably 5 to 70% by weight, and particularly preferably. Is 8 to 60% by weight, most preferably 10 to 55% by weight. If it is less than 1% by weight, the dispersibility may not be excellent. Above 90% by weight, stability may be poor.

[Secondary battery slurry composition, its manufacturing method and application]
The secondary battery slurry composition of the present invention contains a component (A), a component (B), a rheology adjuster (C) and inorganic particles. As the component (A), the component (B), and the rheology adjuster (C), the above-mentioned ones are used.
Further, the secondary battery slurry composition of the present invention may be produced by using the above-mentioned dispersant composition for secondary battery slurry containing the component (A), the component (B) and the rheology adjuster (C). ..

Examples of the inorganic particles in the secondary battery slurry composition include non-conductive particles.
The non-conductive particles are not particularly limited, but for example, alumina (aluminum oxide) such as silica (silicon oxide), α-alumina, β-alumina, γ-alumina, and θ-alumina, titania (titanium oxide), and magnesia. (Magnetic oxide), zirconia (zirconium oxide), calcium oxide, barium oxide, tin oxide, strontium oxide, niobium oxide, cerium oxide, tungsten oxide, indium oxide, gallium oxide, yttrium oxide, iron oxide, antimony oxide, white carbon, etc. Inorganic oxide particles; Inorganic nitride fine particles such as aluminum nitride and silicon nitride; Ionic crystal fine particles such as calcium fluoride, barium fluoride, barium sulfide and calcium sulfide; Covalent crystal fine particles such as silicon and diamond; Mica, Quayates such as talc, bentonite, kaolin, aluminum silicate, and sericite; carbonates such as calcium carbonate, magnesium carbonate, and barium carbonate can be mentioned, and one or more may be used. Of these, α-alumina is preferable because it has particularly high thermal and chemical stability.

The average particle size of the non-conductive particles is not particularly limited, but is usually 0.001 to 100 μm, preferably 0.01 to 10 μm, more preferably 0.1 to 1 μm, and particularly preferably 0.1 to 0.8 μm. Most preferably, it is 0.2 to 0.7 μm. If the average particle size of the non-conductive particles is less than 0.001 μm, production may be difficult and unfavorable. On the other hand, when the average particle size of the non-conductive particles exceeds 100 μm, the dispersibility may be deteriorated, which may not be preferable.

The BET specific surface area of the non-conductive particles is not particularly limited, but is usually 0.1 to 30 m ² / g, preferably 1 to 18 m ² / g, more preferably 4 to 14 m ² / g, and particularly preferably. Is 5 to 10 m ² / g, most preferably 8 to 10 m ² / g. If the BET specific surface area of the non-conductive particles is less than 0.1 m ² / g, the film forming property may be deteriorated, which may not be preferable. On the other hand, when the BET specific surface area of the non-conductive particles exceeds 30 m ² / g, the handleability may be deteriorated, which may not be preferable.

The electrical conductivity of the non-conductive particles is not particularly limited, but is preferably 100 μS / cm or less, more preferably 80 μS / cm or less, particularly preferably 40 μS / cm or less, and most preferably 20 μS / cm or less. is there. If the electrical conductivity of the non-conductive particles exceeds 100 μS / cm, the battery performance may deteriorate, which is not preferable.

The non-conductive particles may contain free metals (or metal ions). The free metal is not particularly limited, and examples thereof include iron, silica, magnesium, sodium, and copper.
The content of the free metal is not particularly limited, but is usually 10000 ppm or less, preferably 1000 ppm or less, more preferably 100 ppm or less, particularly preferably 10 ppm or less, and most preferably 1 ppm or less. If the content of the free metal exceeds 10,000 ppm, the battery performance may be deteriorated, which may be unfavorable.

The secondary battery slurry composition of the present invention satisfies the following condition 4.
Condition 4: The elastic modulus of the molded film made of a non-volatile component consisting of the component (A), the component (B) and the rheology adjuster (C) after swelling of the electrolytic solution is 500 MPa or more.
By setting the elastic modulus after swelling of the electrolytic film of the molding film composed of the non-volatile component consisting of the component (A), the component (B) and the rheology adjuster (C) within this range, the electrode active material during charging and discharging of the battery even in the electrolytic solution. It is possible to withstand the shrinkage of the separator due to the shrinkage of the separator and the sudden heat generation at the time of trouble, and to maintain the binding property of the film. The elastic modulus is more preferably 800 MPa or more, further preferably 1000 MPa or more, and particularly preferably 1500 MPa or more. If it is less than 500 MPa, heat resistance and binding property are insufficient. The upper limit of the preferable elastic modulus is 10,000 MPa. The method for measuring the elastic modulus of a molded film composed of a non-volatile component composed of the component (A), the component (B) and the rheology adjuster (C) after swelling of the electrolytic solution is the method described in Examples.

The secondary battery slurry composition of the present invention satisfies the following condition 5.
Condition 5: The elastic modulus of the molded film composed of the non-volatile component of the mixture of the component (A) and the component (B) is 500 MPa or more.
By setting the elastic modulus of the molded film composed of the non-volatile component composed of the component (A) and the component (B) within this range, it is possible to maintain the overall film strength when mixed with the component (C) which is a rheology adjuster. If the elastic modulus is less than 500 MPa, the overall film strength at the time of mixing with the component (C) is lowered, resulting in insufficient binding property. The preferable range of the elastic modulus of the molded film composed of the non-volatile component of the mixture of (A) and the component (B) and the measuring method are the same as those of the above-mentioned condition 2.

The secondary battery slurry composition of the present invention satisfies the following condition 6.
Condition 6: The glass transition point of the non-volatile component composed of the component (A) and the component (B) is 50 to 150 ° C.
When the non-volatile component composed of the component (A) and the component (B) has a glass transition point in this range, it becomes possible to maintain the heat resistance at the time of mixing with the component (C) which is a rheology adjuster. If the glass transition point of the mixture is less than 50 ° C., the film shrinkage at the time of heat generation cannot be suppressed, and if the glass transition point of the mixture is more than 150 ° C., the film becomes brittle and the binding property becomes insufficient. The preferable range and the measuring method of the glass transition point of the non-volatile component composed of the component (A) and the component (B) are the same as those in the above condition 3.

The zeta potential of the secondary battery slurry composition is not particularly limited, but the zeta potential of the water dispersion having a solid content concentration of 5% by weight at a measurement temperature of 25 ° C. is preferably −10 to 10. -100 mV, more preferably -10 to -90 mV, further preferably -20 to -80 mV, particularly preferably -30 to -70 mV, most preferably 35 to -65 mV. If the zeta potential of the secondary battery slurry composition for surface coating applications at a concentration of 5% by weight is less than -100 mV, the handleability may not be excellent. On the other hand, if the zeta potential of the secondary battery slurry composition for surface coating at a concentration of 5% by weight exceeds -10 mV, the dispersibility may not be sufficient.

The method for producing the secondary battery slurry composition of the present invention is not particularly limited, and for example, a dispersant adjusting step of mixing the dispersant composition for the secondary battery slurry and a solvent, and the dispersant adjusting step. Examples thereof include a production method including an inorganic particle dispersion step of dispersing the inorganic particles in the mixed solution obtained in the above. Specifically, for example, a dispersant composition and a solvent obtained by mixing the components (A) to (C), the component (D), the component (E), and other components as needed. A production method including a step (a) of mixing the above to obtain a dispersant mixed solution and a step (b) of mixing the dispersant mixed solution and the inorganic particles to obtain a slurry composition can be mentioned.

The total of the component (A), the component (B) and the rheology adjuster (C) in the secondary battery slurry composition is not particularly limited, but is 0.1 to 50 parts by weight with respect to 100 parts by weight of the inorganic particles. It is preferably 0.5 to 20 parts by weight, more preferably 1 to 15 parts by weight, still more preferably 2 to 10 parts by weight, and particularly preferably 3 to 7 parts by weight. If it exceeds 50 parts by weight, the battery performance is not excellent. On the other hand, if it is less than 0.1 parts by weight, the coatability may not be sufficient.

In the secondary battery slurry composition, as will be described in detail in the following examples, Rosmiles of an aqueous dispersion having a non-volatile content concentration of 0.1% by weight of the secondary battery slurry composition under measurement conditions at a temperature of 25 ° C. The foaming force is measured by a test method, and the foaming force immediately after the flow of the secondary battery slurry composition is 50 mm or less, preferably 40 mm or less, more preferably 30 mm or less, and particularly preferably 20 mm or less. The foaming force 5 minutes after the flow is 25 mm or less, preferably 20 mm or less, more preferably 15 mm or less, still more preferably 10 mm or less, and particularly preferably 5 mm or less. If the foaming force immediately after flowing down is more than 50 mm according to the Rosmiles test method, the coatability is not sufficient. Further, if the foaming force 5 minutes after the flow is more than 25 mm, the coatability is not sufficient.

The specific gravity of the secondary battery slurry composition is not particularly limited, but is usually 1 to 4, preferably 1.1 to 3, more preferably 1.2 to 2.5, and even more preferably 1.3 to 1. 2, particularly preferably 1.4 to 1.9, and most preferably 1.5 to 1.8. If the specific gravity of the secondary battery slurry composition is more than 4, the dispersion stability may not be excellent. On the other hand, if the specific gravity of the secondary battery slurry composition is less than 1, the coatability may not be excellent.

The pH of the secondary battery slurry composition is not particularly limited, but is preferably 4.0 to 12.0, more preferably 5.0 to 11.0, and particularly preferably 6.0 to 10.0. It is preferably 6.0 to 9.0. If the pH is less than 4.0, the coatability may be poor. If it exceeds 12.0, the handleability may be poor. The pH of the secondary battery slurry composition is measured by the method measured in Examples.

The solvent contained in the secondary battery slurry composition is not particularly limited and may be an organic solvent or water, but water is preferable because of low cost and low risk of harmfulness. The water contained in the secondary battery slurry composition may be tap water, ion-exchanged water, distilled water or the like.

The content of the solvent in the secondary battery slurry composition is not particularly limited, but is, for example, 1 to 10000 parts by weight, preferably 10 to 1000 parts by weight, more preferably 50 to 50 parts by weight, based on 100 parts by weight of the inorganic particles. It is 500 parts by weight, more preferably 60 to 300 parts by weight, particularly preferably 80 to 250 parts by weight, and most preferably 100 to 200 parts by weight. If the content of the solvent in the secondary battery slurry composition is more than 10,000 parts by weight with respect to 100 parts by weight of the inorganic particles, the binding property and heat resistance may be impaired. On the other hand, if the content of the solvent in the secondary battery slurry composition is less than 1 part by weight with respect to 100 parts by weight of the inorganic particles, the coatability may not be sufficient.

In addition to the components described above, the secondary battery slurry composition of the present invention has a hydrotropic agent, a protective colloid agent, an antibacterial agent, a fungicide, a colorant, an antioxidant, a deodorant, a cross-linking agent, and a catalyst. , Emulsion stabilizer, chelating agent and the like may be further contained.

In order to obtain the secondary battery slurry composition of the present invention, the above-mentioned secondary containing the component (A), the component (B), the component (C) (or the component (A), the component (B), and the component (C)). The method of mixing each component such as a dispersant composition for a battery slurry), inorganic particles, and a solvent is not particularly limited, and a device equipped with an extremely simple mechanism such as a container and a stirring blade is used. Can be done. The stirring blade is not particularly limited, and examples thereof include a max blend blade, a tornado blade, and a full zone blade. Further, a mixer capable of general shaking or stirring may be used. Examples of the mixer include a mixer capable of rocking or stirring, such as a ribbon type mixer and a vertical screw type mixer. In addition, Super Mixer (manufactured by Kawata Co., Ltd.), High Speed Mixer (manufactured by Fukae Co., Ltd.), Newgram Machine (manufactured by Seishin Enterprise Co., Ltd.), SV, which are efficient and multifunctional mixers by combining a stirrer. A mixer (manufactured by Shinko Environmental Solutions Co., Ltd.), Filmix (manufactured by Primix Corporation), Jet Paceta (manufactured by Nihon Spindle Manufacturing Co., Ltd.), KRC Kneader (manufactured by Kurimoto Iron Works Co., Ltd.), or the like may be used. Other crushers such as jaw crusher, gyre crusher, cone crusher, roll crusher, impact crusher, hammer crusher, rod mill, ball mill, vibrating rod mill, vibrating ball mill, disc mill, jet mill, cyclone mill, etc. You may use it. Further, an ultrasonic emulsifier, a continuous twin-screw kneader, a high-pressure emulsifier, a microreactor, or the like may be used.

In addition, the method for producing a secondary battery slurry composition of the present invention may include a step of separately dispersing each component constituting the secondary battery slurry dispersant composition in a solvent.
The step of separately dispersing each component constituting the secondary battery slurry composition in the solvent is not particularly limited, but for example, a step of mixing the above components (A) and (B) to obtain a mixed solution ( d) and the step (e) of mixing the rheology adjuster (C) previously dispersed in a solvent to obtain a dispersant composition, and mixing the dispersant composition and inorganic particles to prepare a slurry composition. Examples thereof include a manufacturing method including the obtaining step (f). When at least one selected from the component (D), the component (E) and other components is used, the step of mixing at least one selected from the component (D), the component (E) and the other components is a step of mixing. Any of step (d), step (e), and step (f) may be used, but when mixed in step (d) or step (e), the effect of the present application is obtained by making the dispersant composition uniform. It is preferable because it is easy.

The secondary battery of the present invention contains a positive electrode, a negative electrode, a separator, and an electrolytic solution, and at least one of the positive electrode, the negative electrode, and the separator is formed by a non-volatile component of the secondary battery slurry composition of the present invention. It has a film made of slurry. The "nonvolatile content of the secondary battery slurry composition" is a residue when heated at 110 ° C. and the weight becomes constant.

In a secondary battery, a separator is usually used to prevent a short circuit between a positive electrode and a negative electrode. For example, in the case of a lithium-ion battery, when a short circuit occurs inside the battery, the shutdown function of the separator closes the hole of the separator and prevents the movement of lithium ions in the short-circuited portion, so that the battery in the short-circuited portion cannot move. By losing its function, it plays a role in maintaining the safety of the lithium-ion secondary battery. However, when the battery temperature exceeds, for example, 150 ° C. due to the instantaneous heat generation, the separator may contract rapidly and the short-circuited portion between the positive electrode and the negative electrode may expand. In this case, the battery temperature may reach an abnormally overheated state of several hundred degrees Celsius or higher, which poses a problem in terms of safety. Therefore, as a means for solving the above problems, there is a method of forming a porous film containing preferably non-conductive inorganic particles on the surface of the positive electrode, the negative electrode, or the separator constituting the lithium ion secondary battery.
Each part of the battery of the present invention will be described.
〔electrode〕

When the slurry composition of the present invention is used for an electrode of a secondary battery, the slurry composition is applied to a positive electrode or a negative electrode plate. The coating method may be any method that can be uniformly wet-coated, and is not particularly limited. For example, a capillary coating method, a spin coating method, a slit die coating method, a spray coating method, a dip coating method, a roll coating method, etc. The screen printing method, flexographic printing method, bar coater method, gravure coater method, die coater method, etc. can be adopted.

The film thickness of the surface coating film formed by applying the secondary battery slurry composition of the present invention to the electrode plate and drying it is not particularly limited, but is usually 0.1 to 30 μm, preferably 0.3. It is 10 μm, more preferably 0.5 to 5 μm, particularly preferably 1 to 4 μm, and most preferably 1 to 3 μm. If the film thickness of the surface coat film for one side is less than 0.1 μm, the heat-resistant reinforcing effect may be deteriorated, which may not be preferable. If the film thickness of the surface coating film on one side exceeds 30 μm, the function of the battery may deteriorate, which is not preferable.

The electrode plate is formed by laminating an active material layer containing an active material, a conductive agent, a binder, a reinforcing material, and the like on a current collector. The configuration of the electrode plate will be described below.
The active material of the positive electrode is not particularly limited, but for example, lithium iron phosphate (LiFePO ₄ ), lithium manganese phosphate (LiMnPO ₄ ), lithium cobalt phosphate (LiCoPO ₄ ), iron pyrophosphate (Li ₂ FeP _2). O ₇ ), Lithium cobaltate composite oxide (LiCoO ₂ ), Spinel type lithium manganate lithium cobaltate composite oxide (LiMn ₂ O ₄ ), Lithium manganate composite oxide (LiMnO ₂ ), Lithium nickelate composite oxide (LiNiO _2), lithium composite oxide niobate (LiNbO _2), ferrate lithium composite oxide (LiFeO _2), lithium magnesium acid complex oxide (LiMgO _2), calcium lithium composite oxide (LiCaO _2), copper Lithium acid acid composite oxide (LiCuO ₂ ), lithium zincate composite oxide (LiZnO ₂ ), lithium molybtensate composite oxide (LiMoO ₂ ), lithium tantalate composite oxide (LiTaO ₂ ), lithium tungstate composite oxide (LiZO2) LiWO ₂ ), Lithium-nickel-cobalt-aluminum composite oxide (LiNi _0.8 Co _0.15 Al _0.05 O ₂ ), Lithium-nickel-cobalt-manganese composite oxide (LiNi _0.33 Co _0.33) Mn _0.33 O ₂ , LiNi _0.8 Co _0.1 Mn _0.1 O ₂ ), Manganese Oxide Nickel (LiNi _0.5 Mn _1.5 O ₄ ), Manganese Oxide (MnO ₂ ), Lithium Excess Nickel -Cobalt-manganese composite oxide, nickel hydroxide (Ni (OH) ₂ ), vanadium oxide, sulfur oxide, silicate oxide and the like can be mentioned, and may be one kind or two or more kinds.

The current collector for the positive electrode may be any material that has electron conductivity and can energize the positive electrode material, and is not particularly limited. For example, C, Ti, Cr, Mo, Ru, Rh, Ta, W, Conductive substances such as Os, Ir, Pt, Au, Al, and Ni, and alloys containing two or more of these conductive substances (for example, stainless steel) can be used. C, Al, Ni, stainless steel and the like are preferable as the current collector from the viewpoint of high electrical conductivity, stability in the electrolytic solution and oxidation resistance, and Al and the like are preferable from the viewpoint of material cost. The shape of the current collector is not particularly limited, and for example, a foil-like base material, a three-dimensional base material, or the like can be used. A primer layer may be formed in advance on the surface of the current collector, and the primer layer may contain a conductive auxiliary agent.

The negative electrode active material is not particularly limited, but for example, carbon materials such as natural graphite, artificial graphite, expanded graphite, activated carbon, carbon fiber, coke, soft carbon, and hard carbon; silicon-based; SiO, SnO, SnO ₂ , Metal oxides such as CuO, Li ₄ Ti ₅ O ₁₂ ; Si-Al, Al-Zn, Si-Mg, Al-Ge, Si-Ge, Si-Ag, Zn-Sn, Ge-Ag, Ge-Sn , Ge-Sb, Ag-Sn, Ag-Ge, Sn-Sb and the like; tin phosphate glass type and the like, and may be one kind or two or more kinds.

The current collector of the negative electrode may be any material that has electron conductivity and can energize the negative electrode material, and is not particularly limited. For example, Cu, Ni, C, Ti, Cr, Mo, Ru, Rh, Conductive substances such as Ta, W, Os, Ir, Pt, Au, and Al, and alloys containing two or more of these conductive substances (for example, stainless steel) can be used. Cu, C, Al, stainless steel and the like are preferable as the current collector from the viewpoint of high electrical conductivity, stability in the electrolytic solution and oxidation resistance, and Cu and the like are preferable from the viewpoint of material cost. The shape of the current collector is not particularly limited, and for example, a foil-like base material, a three-dimensional base material, or the like can be used, and specifically, rolled copper foil, electrolytic copper foil, or the like is preferable. A primer layer may be formed in advance on the surface of the current collector, and the primer layer may contain a conductive auxiliary agent.

The electrode active material layer preferably contains an electrode binder in addition to the electrode active material. By including the binder for the electrode, the binding property of the electrode active material layer is improved, and the strength against the mechanical force applied in the process such as when the electrode is sprinkled is increased. Further, since the electrode active material layer is less likely to be peeled off from the current collector, the risk of short circuit due to the peeled detached material is reduced.

As the binder for the electrode, for example, a polymer can be used. Examples of the polymer that can be used as the binder for the electrode include polyethylene, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyimide, tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and polyacrylic acid derivative. , Polyacrylonitrile derivative and the like may be used.

Further, polybutyl acrylate, polybutyl methacrylate, polyhydroxyethyl methacrylate, polyacrylamide, polyacrylonitrile, butyl acrylate / styrene copolymer, butyl acrylate / acrylonitrile copolymer, butyl acrylate / acrylonitrile / glycidyl methacrylate copolymer, etc. A homopolymer of acrylic acid or a methacrylic acid derivative or a copolymer with a copolymerizable monomer thereof, isobutylene soft polymers such as polyisobutylene, isobutylene / isoprene rubber, isobutylene / styrene copolymer, polybutadiene, poly Isoprene, butadiene-styrene random copolymer, isoprene-styrene random copolymer, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-styrene copolymer, butadiene-styrene block copolymer, styrene-butadiene-styrene block Copolymers, isoprene / styrene / block copolymers, diene-based copolymers such as styrene / isoprene / styrene / block copolymers, silicon-containing polymers such as dimethylpolysiloxane, diphenylpolysiloxane, and dihydroxypolysiloxane, liquid polyethylene, Olefin-based products such as polypropylene, poly-1-butene, ethylene / α-olefin copolymer, propylene / α-olefin copolymer, ethylene / propylene / diene copolymer (EPDM), ethylene / propylene / styrene copolymer Polymers, polyvinyl alcohol, polyvinyl acetate, vinyl polystearate, vinyl copolymers such as vinyl acetate / styrene copolymers, epoxy polymers such as polyethylene oxide, polypropylene oxide, epichlorohydrin rubber, vinylidene fluoride rubber, quaternary Using fluorine-containing soft copolymers such as ethylene fluoride-propylene rubber, natural rubbers, polypeptides, proteins, polyester-based thermoplastic elastomers, vinyl chloride-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, and other soft polymers. Is also good.
These polymers may have a crosslinked structure, those having a modified functional group may be used, one type may be used alone, or a plurality of types may be used in combination.

The electrode active material layer may contain any component other than the electrode active material and the binder for electrodes as long as the effects of the present invention are not significantly impaired. Examples thereof include conductive materials and reinforcing materials. In addition, one type of arbitrary component may be used alone, or two or more types may be used in combination at an arbitrary ratio.

The conductive auxiliary agent is not particularly limited, but for example, carbon black such as furnace black, acetylene black, and ketjen black; graphene; carbon nanotubes such as carbon nanofibers, single-walled carbon nanotubes, and multi-walled carbon nanotubes; silver and copper. , Tin, zinc, zinc oxide, nickel, manganese and the like; composite metal fine particles such as indium tin oxide and the like, and may be one kind or two or more kinds.

As the reinforcing material, for example, various inorganic and organic spherical, plate-shaped, rod-shaped or fibrous fillers can be used. By using the reinforcing material, a tough and flexible electrode can be obtained, and excellent long-term cycle characteristics can be obtained.

The method for producing the electrode active material layer is not particularly limited. The electrode active material layer can be produced by applying, for example, an electrode active material and a solvent, and if necessary, an electrode binder and an electrode slurry composition containing an arbitrary component on a current collector and drying the electrode active material layer. As the solvent, either water or an organic solvent can be used.
The method for applying the secondary battery slurry composition to the electrode plate may be any method as long as it can be uniformly wet-coated, and is not particularly limited. For example, a capillary coating method, a spin coating method, a slit die coating method, or a spray coating method is used. The method, dip coating method, roll coating method, screen printing method, flexographic printing method, bar coater method, gravure coater method, die coater method and the like can be adopted.

The method of removing the solvent from the coating film is generally a method of drying. The drying temperature of the solvent is not particularly limited, but is usually 10 to 200 ° C., preferably 30 to 190 ° C., more preferably 50 to 180 ° C., particularly preferably 80 to 170 ° C., and most preferably 90 to 160 ° C. is there. If the drying temperature of the solvent exceeds 200 ° C., the function of the electrode may be deteriorated, which may be unfavorable.

[Separator]
The method for applying the secondary battery slurry composition of the present invention to the separator may be any method as long as it can be uniformly wet-coated, and is not particularly limited. For example, a capillary coating method, a spin coating method, a slit die coating method, and the like. The spray coating method, dip coating method, roll coating method, screen printing method, flexographic printing method, bar coater method, gravure coater method, die coater method and the like can be adopted.

The method of removing the solvent from the coating film is generally a method of drying. The drying temperature of the solvent is preferably a temperature equal to or lower than the softening point of the separator, and is usually 10 to 200 ° C, preferably 30 to 150 ° C, more preferably 40 to 120 ° C, particularly preferably 50 to 100 ° C, and most preferably 60. ~ 90 ° C. If the drying temperature of the solvent exceeds 200 ° C., the function of the separator may be deteriorated, which may be unfavorable.

The resin constituting the composition of the separator is not particularly limited, but for example, a polyolefin resin such as polyethylene, polypropylene, and polybutylene; a polyester resin such as polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; Polyamide-based resins such as nylon; polyamideimide-based resins; polyacetal-based resins; polystyrene-based resins; methacrylic-based resins; polyvinyl chloride-based resins; polycarbonate-based resins; polyphenylene sulfide-based resins, cellulose-based resins and the like can be mentioned.

The shape of the separator is not particularly limited, and examples thereof include a microporous membrane film and a non-woven fabric.
The surface of the separator may be surface-coated with a polyvinylidene fluoride resin, a polyaramid resin, or the like before applying the secondary battery slurry composition.
The separator may be hydrophilized before applying the secondary battery slurry composition. Examples of the hydrophilization treatment include chemical treatment with an acid or alkali, corona treatment, and plasma treatment.

The surface coating film formed by applying the secondary battery slurry composition of the present invention to the surface of the separator and drying it may be formed on either one side of the separator or on both sides.

The film thickness of the surface coating film for one side formed by applying the secondary battery slurry composition of the present invention to the surface of the separator and drying it is not particularly limited, but is usually 0.1 to 30 μm, preferably 0.1 to 30 μm. It is 0.3 to 10 μm, more preferably 0.5 to 5 μm, particularly preferably 1 to 4 μm, and most preferably 1 to 3 μm. If the film thickness of the surface coating film on one side is less than 0.1 μm, the heat resistance may deteriorate, which may not be preferable. If the film thickness of the surface coating film on one side exceeds 30 μm, the function of the separator may deteriorate, which is not preferable.

The film thickness of the separator coated with the secondary battery slurry composition of the present invention, dried and surface-coated is not particularly limited, but is usually 1 to 100 μm, preferably 5 to 50 μm, and more preferably 10 to 10 μm. It is 30 μm, particularly preferably 15 to 25 μm, and most preferably 20 to 25 μm. If the film thickness of the surface-coated separator is less than 1 μm, the heat resistance may deteriorate, which may not be preferable. If the film thickness of the surface coating film on one side exceeds 100 μm, the function of the separator may deteriorate, which is not preferable.

It is preferable that the contact angle of the solvent with respect to the separator coated with the secondary battery slurry composition, dried and surface-coated is within a specific range because the battery performance is excellent.
The contact angle of the electrolytic solution (1: 1 mixture of ethylene carbonate and dimethyl carbonate) with respect to the separator coated with the secondary battery slurry composition of the present invention, dried and surface-coated is not particularly limited, but for example. After 1600 msec has elapsed from the dropping of the electrolytic solution, it is usually 80 ° or less, preferably 70 ° or less, more preferably 60 ° or less, still more preferably 55 ° or less, and particularly preferably 50 ° or less. If the contact angle of the electrolytic solution with respect to the surface-coated separator is more than 80 °, the battery performance may not be excellent.

[Materials for secondary batteries and their manufacturing methods]
Examples of the material for the secondary battery of the present invention include the positive electrode, the negative electrode, and the separator described in each application of the secondary battery slurry composition. That is, at least one of the electrode plate and the separator of the positive electrode and the negative electrode of the present invention is formed by the non-volatile component of the secondary battery slurry composition.

The method for producing the material for the secondary battery of the present invention is not particularly limited, but for example, the components (A) to (C) are mixed with the component (D), the component (E), and other components as needed. The step (a) of mixing the obtained dispersant composition for a secondary battery slurry and a solvent to obtain a dispersant mixed solution, and mixing the obtained dispersant mixed solution and inorganic particles to prepare a slurry composition. Examples thereof include a manufacturing method including a step (b) of obtaining the slurry composition and a step (c) of applying the slurry composition to at least one selected from the positive electrode plate, the negative electrode plate and the separator, and drying the slurry composition to form a film. The step of mixing at least one selected from the component (E) and the other components may be either step (a) or step (b), but when mixed in step (a), the dispersant composition Is preferable because the effect of the present application can be easily obtained by making the amount uniform.
As for the coating method and the drying method, the methods described above for each application of the above secondary battery slurry composition can be adopted.

[Secondary battery]
The secondary battery of the present invention can be produced by using at least one of a positive electrode, a negative electrode, and a separator produced by using the secondary battery slurry composition of the present invention, and the production method thereof is not particularly limited. For example, the above-mentioned negative electrode and positive electrode are superposed via a separator and wound, folded, or laminated according to the shape of the battery to prepare an electrode body, which is placed in a battery container, and an electrolytic solution is injected into the battery container to seal the battery. You may.

The shape of the battery is not particularly limited, and examples thereof include a coin type, a cylindrical type, a square type, and a sheet type.
The exterior method of the battery is not particularly limited, and examples thereof include a metal case, a mold resin, and an aluminum laminated film.

The type of secondary battery is not particularly limited, and is a lithium ion secondary battery such as a lithium ion battery or a lithium ion polymer battery; an alkaline secondary battery such as a nickel hydrogen battery or a nickel cadmium battery; a sodium sulfur battery; a redox flow battery. ; Examples include air batteries.
The electrolytic solution is not particularly limited, but in the case of a lithium ion battery, for example, a solution in which a lithium salt is dissolved as a supporting electrolyte in a non-aqueous solvent can be used. Examples of the lithium salt include LiPF ₆ , LiAsF ₆ , LiBF ₄ , LiSbF ₆ , LiAlCl ₄ , LiClO ₄ , CF ₃ SO ₃ Li, C ₄ H ₉ SO ₃ Li, CF ₃ COOLi, (CF ₃ CO) ₂ NLi. , (CF ₃ SO ₂ ) ₂ NLi, (C ₂ F ₅ SO ₂ ) ₂ NLi and the like, and may be one kind or two or more kinds. The solvent used in the electrolytic solution is not particularly limited as long as it can dissolve the supporting electrolyte, and is, for example, an alkyl carbonate compound such as dimethyl carbonate, ethylene carbonate, diethyl carbonate, propylene carbonate, butylene carbonate, methyl ethyl carbonate; -Ester compounds such as butyrolactone and methyl formate; ether compounds such as 1,2 dimethoxyethane and tetrahydrofuran; sulfur-containing compounds such as sulfolane and dimethyl sulfoxide can be mentioned. Other additives may be mixed in the electrolytic solution, and examples thereof include vinylene carbonate.

When the secondary battery is a nickel-metal hydride battery, the electrolytic solution is not particularly limited and may be an alkaline aqueous solution, and examples thereof include an aqueous solution containing potassium hydroxide and sodium hydroxide.
The secondary battery of the present invention can be used as a power source for various electric devices (including vehicles that use electricity).

Electrical equipment includes, for example, air conditioners, washing machines, televisions, refrigerators, freezers, cooling equipment, laptop computers, tablets, smartphones, personal computer keyboards, personal computer displays, desktop personal computers, CRT monitors, personal computer racks, printers, and integrated personal computers. , Mouse, hard disk, personal computer peripherals, iron, clothes dryer, window fan, transceiver, blower, ventilation fan, music recorder, music player, oven, range, toilet seat with cleaning function, warm air heater, car component, car navigation system, flashlight, Humidifier, portable karaoke machine, ventilation fan, dryer, dry battery, air purifier, mobile phone, emergency electric light, game machine, blood pressure monitor, coffee mill, coffee maker, kotatsu, copy machine, disc changer, radio, shaver, juicer , Shredder, water purifier, lighting equipment, dehumidifier, dish dryer, rice cooker, stereo, stove, speaker, trouser press, vacuum cleaner, body fat scale, weight scale, health meter, movie player, electric carpet, electric kettle, Rice cooker, electric razor, electric stand, electric pot, electronic game machine, portable game machine, electronic dictionary, electronic notebook, microwave oven, electromagnetic cooker, calculator, electric cart, electric wheelchair, electric tool, electric toothbrush, anka, Haircuts, phones, watches, interphones, air circulators, electric shock pesticides, copying machines, hot plates, toasters, dryers, electric drills, rice cookers, panel heaters, crushers, soldering irons, video cameras, video decks, facsimiles, Fan heater, food processor, duvet dryer, headphones, electric pot, hot carpet, microphone, massage machine, miniature bulb, mixer, sewing machine, rice cooker, floor heating panel, lantern, remote control, cooler, colder, freezer stocker, Cold air heaters, word processors, whisks, electronic musical instruments, motorcycles, toys, lawn mowers, squirrels, bicycles, automobiles, hybrid automobiles, plug-in hybrid automobiles, electric automobiles, railways, ships, airplanes, emergency storage batteries, etc. Can be mentioned.

Hereinafter, examples of the present invention will be specifically described together with comparative examples thereof. The present invention is not limited to these examples.

[Measurement of viscosity]
Prepare a 20% water dispersion of component (A) and a 4% water dispersion of component (B), and use a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd .: BL type) in an atmosphere of 25 ° C. Was measured.

[Measurement of pH]
A pH meter (Horiba Seisakusho Co., Ltd.) measures the pH of the aqueous dispersion having a non-volatile content of 10% by weight and the aqueous dispersion having a non-volatile content of 40% by weight of the secondary battery slurry composition at 25 ° C. , F-51) was used for each measurement.

[Foaming power]
The measurement was carried out under measurement conditions at a temperature of 25 ° C. by the Rosmiles test method based on the method of JIS K3362. 50 ml of the test solution was prepared by using a 0.1% by weight aqueous dispersion having a non-volatile content of the dispersant composition for the secondary battery slurry or a 0.1% by weight aqueous dispersion having a non-volatile content of the secondary battery slurry composition as the test solution. Was poured along the tube wall of the Rosmile measuring device, and 200 ml of the test solution was also put into the upper flow pipette to prepare the mixture. Set the pipette so that the droplets of the test solution fall into the center of the cylinder of the Rosmiles measuring device, let the test solution flow down from a height of 90 cm, and the height of the foam immediately after the flow is completed (immediately after the flow down) and immediately after the flow down The height of the foam was measured 5 minutes after the above. The effective concentration here refers to the weight ratio of the absolute dry component when the composition is heat-treated at 105 ° C. to remove the solvent and the like with respect to the weight of the composition and reaches a constant amount.

〔surface tension〕
Using an aqueous dispersion of 0.1% by weight of non-volatile content of the dispersant composition for secondary battery slurry as a test solution, measure the temperature at 25 ° C. by the Wilhelmy method using an automatic surface tension meter (manufactured by KRUSS, product number Tensiometer K100). Measured under conditions.

[Contact angle]
A non-volatile content concentration of 1.0 wt% aqueous dispersion of the dispersant composition for the secondary battery slurry was used as a test solution, and the measurement was performed using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., product number DM-901).

[Measurement of glass transition point]
The measurement was performed using a dynamic viscoelasticity measuring device (manufactured by TA Instruments, product number Q800).

[Measurement of thermogravimetric analysis (TGA)]
The measurement was performed using a differential thermal balance (manufactured by Rigaku Co., Ltd., product number Thermo plus EVO) under the measurement conditions of a set start temperature of 20 ° C., a set final temperature of 300 ° C., and a heating rate of 10 ° C. per minute.

[Measurement of average particle size and zeta potential]
It was measured using a particle size / zeta potential measurement system (ELSZ-1000 manufactured by Otsuka Electronics Co., Ltd.).

[Measurement of swelling degree with respect to electrolyte]
0.2 g of each solid of the dried components (A) and (B) was immersed in an electrolytic solution (1: 1 mixture of ethylene carbonate and dimethyl carbonate) under 60 ° C. conditions for 6 hours. Then, the test piece was taken out from the electrolytic solution, the electrolytic solution on the surface of the test piece was wiped off, and the weight W2 of the test piece after immersion was measured. The weight of the test piece before immersion in the electrolytic solution was defined as W1, and the swelling degree SW (times) with respect to the electrolytic solution was calculated and calculated with SW = W2 / W1.

[Measurement of elastic modulus]
The aqueous solution of the mixture of the component (A) and the component (B) was adjusted so as to have a non-volatile content concentration of 10% by weight, and the adjusted aqueous solution was applied onto the release paper using a coating machine, and the amount was constant at 110 ° C. By drying until it became thick, a molded film composed of a non-volatile component composed of the component (A) and the component (B) having a thickness of 30 μm was obtained. The obtained molded film was cut into strips of 10 × 70 mm and used for measurement. The measurement was performed using a tensile compression tester TG-2kN manufactured by Minebea Co., Ltd. at a temperature of 20 ° C., with a chuck distance of 30 mm and a tensile speed of 100 mm / min, and an average value of elastic modulus for 5 samples. Was used as the measured value.

[Measurement of elastic modulus after swelling of electrolyte]
The aqueous dispersion is adjusted so that the dispersant composition for the secondary battery slurry has a non-volatile content concentration of 10%, and the adjusted aqueous dispersion is applied onto the release paper using a coating machine, and at 110 ° C. By drying until it became a constant amount, a molded film made of a non-volatile component of a dispersant composition for a secondary battery having a thickness of 30 μm was obtained. The obtained molding film composed of the non-volatile component was moistened in an electrolytic solution (1: 1 mixed solution of ethylene carbonate and dimethyl carbonate) at 80 ° C. for 1 hour and then at 25 ° C. for 24 hours, and the electrolytic solution was wiped off. It was cut into strips of 10 x 70 mm and used for measurement. For the measurement, a tensile compression tester TG-2kN manufactured by Minebea Co., Ltd. was used to perform a tensile test at a temperature of 20 ° C. with a chuck distance of 30 mm and a tensile speed of 100 mm / min, and the film thickness after wetting was measured separately. Then, the elastic moduli of 5 points of the sample were calculated, and the average value thereof was used as the measured value.
Further, the aqueous solution of the mixture of the component (A), the component (B) and the component (C) is adjusted to have a non-volatile content concentration of 10% by weight, and the adjusted aqueous dispersion is applied onto the release paper using a coating machine. By working and drying at 110 ° C. until the amount became constant, a molded film composed of a non-volatile component composed of a component (A), a component (B) and a component (C) having a thickness of 30 μm was obtained. The obtained molding film composed of the non-volatile component was moistened in an electrolytic solution (1: 1 mixed solution of ethylene carbonate and dimethyl carbonate) at 80 ° C. for 1 hour and then at 25 ° C. for 24 hours, and the electrolytic solution was wiped off. It was cut into strips of 10 x 70 mm and used for measurement. For the measurement, a tensile compression tester TG-2kN manufactured by Minebea Co., Ltd. was used to perform a tensile test at a temperature of 20 ° C. with a chuck distance of 30 mm and a tensile speed of 100 mm / min, and the film thickness after wetting was measured separately. Then, the elastic moduli of 5 points of the sample were calculated, and the average value thereof was used as the measured value.

[Evaluation of dispersion stability]
The prepared secondary battery slurry composition was placed in a 100 ml centrifuge tube and stored at room temperature for 24 hours, and then the weight of the sediment was measured. The evaluation criteria for dispersion stability are as follows.
⊚: The weight of the sediment is less than 5% by weight, and the dispersion stability is excellent.
◯: The weight of the sediment is 5% by weight or more and less than 10% by weight, and the dispersion stability is excellent.
Δ: The weight of the sediment is 10% by weight or more and less than 30% by weight, and the dispersion stability is inferior.
X: The weight of the sediment is 30% by weight or more, and the dispersion stability is inferior.

[Evaluation of coatability]
(In the case of separator)
The prepared secondary battery slurry composition was applied to the surface of a polyolefin-based separator at 15 g / m ² , heated to a temperature of 80 ° C., and dried. The covering area of the separator surface coated on the surface was measured. The evaluation criteria for coatability are as follows.
⊚: The covering area is 95% or more, and the coatability is excellent.
◯: The covering area is 90% or more and less than 95%, and the coating property is excellent.
Δ: The covering area is 80% or more and less than 90%, and the coatability is inferior.
X: The covering area is less than 80%, and the coatability is inferior.

(For positive and negative electrodes)
The prepared secondary battery slurry composition was applied to the electrode plate active material layer at 10 mg / cm ² and heated to a temperature of 150 ° C. for drying. The covering area of the surface of the current collector was measured. The evaluation criteria for coatability are as follows.
◯: The coating area is 95% or more, the coating surface is not cracked during drying, and the coating property is excellent.
X: Cracks occur on the coated surface during drying, and the covering area is less than 95%, resulting in poor coatability.

[Evaluation of dryness]
(In the case of separator)
15 g / m ^{2 of the} prepared secondary battery slurry composition is applied to the surface of the polyolefin-based separator, and the time until the applied surface dries at a temperature of 80 ° C. is visually measured. The evaluation criteria for dryness are as follows.
◯: When the drying time is 30 seconds or less, the waiting time is short and the drying property is good.
X: If the drying time is more than 30 seconds, the waiting time is long and the workability is hindered, so that the drying property is not good.

(In the case of electrodes)
The prepared secondary battery slurry composition is coated on the electrode plate active material layer at 10 mg / cm ² and the time until the coated surface dries at a temperature of 150 ° C. is visually measured. The evaluation criteria for dryness are as follows.
◯: When the drying time is 300 seconds or less, the waiting time is short and the drying property is good.
X: If the drying time is more than 300 seconds, the waiting time is long and the workability is hindered, so that the drying property is not good.

[Evaluation of heat resistance]
The sample length 10 cm × width 10 cm of the prepared surface-coated separator was stored in a constant temperature bath at 120 ° C. for 8 hours and heated, and then the length and width of each sample were measured to calculate the shrinkage rate. The evaluation criteria for heat resistance are as follows. The heat resistance of the surface-coated separator was evaluated by the shrinkage rate, whichever is smaller, vertical or horizontal.
Shrinkage rate (%) = (length or width of surface coated separator after heating for 8 hours / 10) x 100
⊚: The shrinkage rate is 95% or more, and the heat resistance is particularly excellent.
〇: The shrinkage rate is 90% or more and less than 95%, and the heat resistance is excellent.
Δ: The shrinkage rate is 80% or more and less than 90%, and the heat resistance is inferior.
X: The shrinkage rate is less than 80%, and the heat resistance is inferior.

[Evaluation of cohesiveness]
(In the case of separator)
A cellophane tape having a width of 38 mm (specified in JIS Z1522) is attached to the slurry adhesion surface on the separators obtained in Examples and Comparative Examples, and a load of 100 g / cm ² is applied at 20 ° C. for 1 hour. With respect to the obtained sample, one end of the separator was peeled off by pulling it in the 180 ° direction toward the end facing the one end of the separator at a tensile speed of 100 mm / min, and the stress at that time was measured. The measurement was performed three times, the average value was obtained, and this was used as the peel strength, and evaluated according to the following criteria. The greater the peel strength, the greater the binding force between the slurry drying film and the separator base material.
⊚: The peel strength is 1.0 N / 38 mm or more, and the binding property is particularly excellent.
〇: The peel strength is 0.5 N / 38 mm or more, and the binding property is excellent.
Δ: The peel strength is 0.1 N / 38 mm or more, and the binding property is inferior.
X: The peel strength is less than 0.1 N / 38 mm, and the binding property is particularly inferior.
(In the case of electrodes)
When the slurry of the present invention is applied to the surface of the electrode active material layer by the methods of Examples and Comparative Examples, the uncoated surface of the slurry is left. A 38 mm wide cellophane tape (specified in JIS Z1522) is attached to the slurry adhesion surface on the separator, and a load of 100 g / cm ² is applied at 20 ° C. for 1 hour. With respect to the obtained sample, one end of the electrode plate was pulled and peeled off in a 180 ° direction toward the end facing the one end of the electrode plate at a tensile speed of 100 mm / min, and the stress at that time was measured. On the other hand, the peel strength was measured on the slurry-free surface of the same sample by the same procedure, the respective values were compared, and the evaluation was made according to the following criteria. When the slurry adhering surface has a higher peel strength than the slurry non-adhering surface, it can be judged that the slurry has sufficient binding property.
◯: Peel strength of the slurry-adhered surface> Peel strength of the non-slurry-attached surface and excellent binding property Δ: Peel strength of the slurry-attached surface = Peel strength of the non-slurry-attached surface and inferior in binding property.
X: Peel strength of the slurry-adhered surface <Peel strength of the slurry-non-adhered surface, which is inferior in binding property.

[Evaluation of liquid retention of electrolyte]
Using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., product number DM-901), an equivalent mixture of ethylene carbonate and dimethyl carbonate is dropped onto any of the surface coated separator, positive electrode, and negative electrode, and contact is performed after 1600 msec has elapsed. The angle was measured and evaluated.
⊚: The contact angle is less than 20 °, and the liquid retention property of the electrolytic solution is particularly excellent.
〇: The contact angle is 20 ° or more and less than 30 °, and the electrolyte has excellent liquid retention.
Δ: The contact angle is 30 ° or more and less than 40 °, and the liquid retention property of the electrolytic solution is inferior.
X: The contact angle is 40 ° or more, and the liquid retention property of the electrolytic solution is particularly inferior.

(Manufacturing of positive electrode plate)
95 g of lithium cobalt oxide, 5 g of acetylene black, and 3 g of PVDF NMP (N-methylpyrrolidone) solution as a binder were added in terms of solid content, and NMP was added and mixed so that the total solid content was 70%. This was applied to an aluminum foil having a film thickness of 20 μm and dried in an oven at 150 ° C. to obtain a positive electrode plate for a secondary battery.

(Manufacturing of negative electrode plate)
95 g of graphite, 5 g of acetylene black, 1.2 g of aqueous solution of carboxylmethylcellulose as a binder equivalent to solid content, 1.8 g of aqueous dispersion of styrene-butadiene copolymer equivalent to solid content, and water to add 70% of total solid content. Mixed as such. This was applied to a copper foil having a film thickness of 18 μm and dried in an oven at 150 ° C. to obtain a negative electrode plate for a secondary battery.

[Component (A)]
Regarding the component (A) and the production comparative example used in Examples and Comparative Examples, their specific production methods and physical properties are shown in Production Examples A-1 to A-5 and H-1 in Table 1 below.

[Component (B)]
The specific physical properties of the component (B) used in Examples and Comparative Examples are shown in B-1 to B-5 of Table 2 below.

[Rheology adjuster (C)]
As a rheology adjuster, carboxymethyl cellulose (with a degree of etherification of 0.7 and a viscosity of 1% by weight at 20 ° C. of 10 mPa · s) was used.

[Defoamer]
The antifoaming agents used in Examples and Comparative Examples are shown below.
Polysiloxane defoamer: dimethylpolysiloxane, viscosity 100 mPa · s
Silica fine powder defoamer: Silica fine powder mineral oil hydrophobized with trimethylethoxysilane: Paraffin mineral oil

[Inorganic particles]
The inorganic particles used in Examples and Comparative Examples are shown below.
α-alumina 1: Primary particle diameter 0.3 μm, BET specific surface area 8.4 m ² / g
α-alumina 2: Primary particle diameter 0.8 μm, BET specific surface area 4.9 m ² / g
γ-Alumina: Primary particle diameter 0.3 μm, BET specific surface area 4.7 m ² / g
θ alumina: primary particle diameter 0.3 μm, BET specific surface area 5.3 m ² / g

[Manufacturing Example A-1]
First, 15 g of acrylic acid, 5 g of acrylonitrile and 80 g of acrylamide were prepared as the polymerizable monomer, and 2.0 g of the sodium alkylbenzene sulfonic acid salt was prepared as the emulsifier.
The polymerizable monomer and emulsifier prepared above and 400 g of ion-exchanged water are mixed and stirred with a homogenizer, and reacted in a 500 ml separable flask under a nitrogen stream at 80 ° C. for 3 hours to obtain component A-1. Obtained. This component A-1 was water-soluble, had a non-volatile content concentration of 20.3% by weight, a viscosity of 18,000 mPa · s, a thermogravimetric measurement of 5.4%, and a glass transition point of 157 ° C.
[Production Examples A-2 to A-5, Production Comparative Example H-1]
In Production Examples A-2 to A-5 and Comparative Production Example H-1, water solubility is the same as in Production Example A-1 except that the raw materials are changed in Production Example A-1 as shown in Table 2 above. The polymers were obtained and their physical properties were evaluated in the same manner as in Production Example A-1.

[Manufacturing Example 1]
25 g of a polymer aqueous solution containing 5 g of the water-soluble polymer A-1 as the component (A), 5 g of B-1 as the component (B), and 10 g of the above-mentioned carboxylmethyl cellulose and POE as the rheology adjuster (C). (12) 1 g of lauryl ether and 160 g of ion-exchanged water were uniformly mixed to obtain a dispersant composition for a secondary battery slurry. The amount of ion-exchanged water was 180 g including the ion-exchanged water contained in the polymer component. The dispersant composition for the secondary battery slurry has a non-volatile content concentration of 10.4%, a viscosity of 1500 mPa · s, a pH of 8.0, a surface tension of 33.6 mN / m, a zeta potential of -30 mV, and a foaming force of 80 mm immediately after. After 5 minutes, the value was 20 mm, the contact angle with the alumina plate as an inorganic oxide plate was 45 ° after 1600 msec, and the contact angle with the polyolefin resin was 21 ° after 1600 msec.
[Production Examples 2 to 17, Production Comparative Examples 18 to 21]
In Production Examples 2 to 17 and Comparative Production Examples 18 to 21, the dispersant composition for the next battery slurry was obtained in the same manner as in Production Example 1 except that the raw materials were changed as shown in Tables 3 to 5, respectively, and the physical properties were obtained. Etc. were also evaluated in the same manner as in Production Example 1. The results are shown in Tables 3-5.

[Example 1]
A secondary battery slurry composition is obtained by uniformly mixing 100 g of α-alumina 1 which is an inorganic powder, a secondary battery electrode which is a dispersant, 30 g of the dispersant composition shown in Production Example 1, and 100 g of ion-exchanged water. Obtained.
The obtained secondary battery slurry had a non-volatile content concentration of 46.6% by weight, a viscosity of 100 mPa · s, an average particle diameter of 380 nm, a zeta potential of −48 mV, and a foaming force of 15 mm immediately after and 5 mm after 5 minutes. Met.
When the dispersion stability of the dispersant composition for the secondary battery slurry was evaluated using this secondary battery slurry composition, the weight of the precipitate was less than 5% by weight, and the dispersion stability was excellent.
The secondary battery slurry composition obtained above was applied to a polyolefin resin-based separator having a film thickness of 20 μm, and dried in an oven at 80 ° C. According to visual observation, it was dried in less than 30 seconds and was excellent in drying property. The coating area of the separator surface coated after drying was 95% or more, and the coatability was excellent. The surface coating film thickness was 4 μm. The surface-coated separator whose surface is surface-coated has a shrinkage rate of 95% or more, excellent heat resistance, a peel strength of 1.5 N / mm, excellent binding properties, and excellent liquid retention of the electrolytic solution. Was there.
Further, the secondary battery slurry composition obtained above was applied to the positive electrode and negative electrode plates described above, and dried in an oven at 150 ° C. Both the positive and negative electrodes were dried in less than 300 seconds according to visual observation, and were excellent in drying property. In addition, the coating area after drying was 95% or more, and there were no cracks on the coated surface during drying, and the coating property was excellent. The surface coating film thickness was 3 μm. The peel strength was higher than that of the positive and negative electrode plates before coating, and the binding property was excellent, and the liquid retention property of the electrolytic solution was also excellent.

[Examples 2 to 17]
In Examples 2 to 17, the secondary battery slurry composition was obtained in the same manner as in Example 1 except that the raw materials were changed as shown in Tables 6 and 7, respectively, and the physical properties were also carried out. Evaluation was performed in the same manner as in Example 1. The results are shown in Tables 6 and 7.

[Comparative Example 1]
A secondary battery slurry is obtained by uniformly mixing 100 g of α-alumina 1 which is an inorganic powder, a secondary battery electrode which is a dispersant, 30 g of the dispersant composition 18 shown in the production comparative example, and 100 g of ion-exchanged water. It was.
The obtained secondary battery slurry composition had a non-volatile content concentration of 44.8% by weight, a viscosity of 100 mPa · s, an average particle diameter of 350 nm, a zeta potential of −45 mV, and a foaming force of 15 mm immediately after and 5 minutes later. Was 5 mm.
The secondary battery slurry obtained above was applied to a polyolefin resin-based separator having a film thickness of 20 μm, and dried in an oven at 80 ° C. The surface coating film thickness was 3 μm. The surface-coated separator whose surface was surface-coated had a shrinkage rate of 80% and was inferior in heat resistance. The peel strength of the separator was 0.1 N / mm, and the binding property was inferior.
Further, the secondary battery slurry composition obtained above was applied to the positive electrode and negative electrode plates described above, and dried in an oven at 150 ° C. The surface coating film thickness was 3 μm. The peel strength was lower than that of the positive and negative electrode plates before coating, and the binding property was inferior.
[Comparative Examples 2 to 4]
In Comparative Examples 2 to 4, the secondary battery slurry compositions were obtained in the same manner as in Comparative Example 1 except that the raw materials were changed as shown in Table 8 in Comparative Example 1, and the physical properties were also the same as those in Comparative Example 1. Evaluated in the same way. The results are shown in Table 8.

As can be seen from Tables 6 and 7, the secondary battery slurry compositions of Examples 1 to 17 have a dispersant composition for a secondary battery slurry containing the component (A), the component (B) and the rheology adjuster (C). The component (A) is a water-soluble polymer containing 70% by weight or more of a nitrogen atom-containing monomer unit, and the component (B) contains 60 to 99% of a hydroxyl group-containing monomer unit. It is a water-soluble polymer having a degree of polymerization of 100 to 10,000, and the elasticity of a molded film made of a non-volatile component of a dispersant composition for a secondary battery slurry after swelling of an electrolytic solution is 500 MPa or more, and the component (A) and the component Dispersant for secondary battery slurry, wherein the molding film composed of the non-volatile component of the mixture of (B) has an elasticity of 500 MPa or more, and the glass transition point of the mixture of the component (A) and the component (B) is 50 to 150 ° C. Since it contains a composition, it has excellent coating properties and film drying properties. Further, the separator coated with this secondary battery slurry composition has excellent heat resistance.
On the other hand, as can be seen from Table 8, when the component (A) shown in Comparative Examples 1 and 3 is absent, and when the component (B) shown in Comparative Example 2 is absent, the rheology adjuster (C) shown in Comparative Example 4 is present. If there is no, one of the problems of the present application has not been solved.

Claims (10)

A dispersant composition containing the following component (A), the following component (B), and a rheology adjuster (C), which satisfies the following conditions 1 to 3 for a secondary battery slurry.
Component (A): Water-soluble polymer component containing 70% by weight or more of nitrogen atom-containing monomer unit (B): 60 to 99% by weight of hydroxyl group-containing monomer unit, and the degree of polymerization is 100 to 10,000. Water-soluble polymer Condition 1: The elastic modulus of the molded film made of the non-volatile component of the dispersant composition after swelling of the electrolytic solution is 500 MPa or more.
Condition 2: The elastic modulus of the molded film composed of the non-volatile component composed of the component (A) and the component (B) is 500 MPa or more.
Condition 3: The glass transition point of the non-volatile component composed of the component (A) and the component (B) is 50 to 150 ° C. The dispersant composition for a secondary battery slurry according to claim 1, further containing a surfactant (D). The weight ratio (B / A) of the component (B) to the component (A) is 0.2 to 3.0, and the total content of the component (A) and the component (B) is 100 parts by weight. When the content of the rheology adjuster (C) is 0.5 to 200 parts by weight, the total content of the component (A), the component (B) and the rheology adjuster (C) is determined. The dispersant composition for a secondary battery slurry according to claim 2, wherein the content of the surfactant (D) is 0.01 to 20 parts by weight when the content is 100 parts by weight. The dispersant composition for a secondary battery slurry according to any one of claims 1 to 3, wherein the viscosity of the 4% by weight aqueous solution of the component (B) at 20 ° C. is 1 to 500 mPa · s. The rheology adjuster (C) is carboxymethyl cellulose having an etherification degree of 0.55 to 1.1 and a viscosity of a 1% by mass aqueous solution of 1 to 100 mPa · s at 20 ° C. The dispersant composition for a secondary battery slurry according to any one. A secondary battery slurry composition containing the following component (A), the following component (B), a rheology adjuster (C), and inorganic particles, when the content of the inorganic particles is 100 parts by weight, the following A secondary battery slurry composition in which the total of the component (A), the following component (B) and the rheology adjusting agent (C) is 0.1 to 50 parts by weight, and the following conditions 4 to 6 are satisfied.
Component (A): Water-soluble polymer component containing 70% by weight or more of nitrogen atom-containing monomer unit (B): 60 to 99% by weight of hydroxyl group-containing monomer unit, and the degree of polymerization is 100 to 10,000. Water-soluble polymer condition 4: The elasticity of the molded film composed of the component (A), the component (B) and the rheology adjuster (C) after swelling of the electrolytic solution is 500 MPa or more.
Condition 5: The elastic modulus of the molded film composed of the non-volatile component composed of the component (A) and the component (B) is 500 MPa or more.
Condition 6: The glass transition point of the non-volatile component composed of the component (A) and the component (B) is 50 to 150 ° C. The step (a) of mixing the dispersant composition for a secondary battery slurry according to any one of claims 1 to 5 with a solvent to obtain a dispersant mixed solution, and mixing the dispersant mixed solution and inorganic particles. (B) for obtaining a slurry composition, and (c) for applying the slurry composition to at least one selected from a positive electrode, a negative electrode, and a separator and drying the slurry composition to form a film. How to make the material. An electrode having a coating film on an electrode plate, wherein the coating film is formed of a non-volatile component of the secondary battery slurry composition according to claim 6. A separator for a secondary battery, which is a separator having a coating for a separator, wherein the coating is formed of a non-volatile component of the secondary battery slurry composition according to claim 6. A secondary battery including a positive electrode, a negative electrode, a separator and an electrolytic solution, wherein at least one selected from the positive electrode, the negative electrode and the separator is formed of the non-volatile component of the secondary battery slurry composition according to claim 6. A secondary battery having a coating film.