JP2017098204A - Nonaqueous secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonaqueous secondary battery which is high in adhesiveness between battery members, including electrodes and separator, and superior in battery performance, such as cycle characteristics, and output characteristics.SOLUTION: A nonaqueous secondary battery comprises: a positive electrode; a negative electrode; a separator; an electrolytic solution; and an adhesive layer. The negative electrode includes: a negative electrode active material; and a binding material A for a negative electrode which includes 70-95 mass% of (meth)acrylic acid ester monomer units and 1-5 mass% of ethylenic unsaturated carboxylic acid monomer units. The adhesive layer is disposed between the negative electrode and the separator, and includes a particulate polymer having a glass transition temperature of 110°C or below.SELECTED DRAWING: None

Description

  The present invention relates to a non-aqueous secondary battery.

  Non-aqueous secondary batteries such as lithium ion secondary batteries (hereinafter sometimes simply referred to as “secondary batteries”) have the characteristics of being small and lightweight, having high energy density, and capable of repeated charge and discharge. Yes, it is used for a wide range of purposes. Therefore, in recent years, the improvement of battery members has been studied for the purpose of further improving the performance of non-aqueous secondary batteries.

  Here, the battery member of the secondary battery generally includes electrodes such as a positive electrode and a negative electrode, and a separator that separates the positive electrode and the negative electrode to prevent a short circuit between the positive electrode and the negative electrode. And a secondary battery is normally manufactured by inject | pouring electrolyte solution into the assembly which assembled these battery members. In addition, an adhesive layer or the like for the purpose of improving the adhesion between battery members may be provided between the electrode and the separator.

  Moreover, the electrode for secondary batteries, such as a lithium ion secondary battery, is normally equipped with the electrical power collector and the electrode compound-material layer formed on the electrical power collector. The electrode mixture layer is formed, for example, by applying a slurry composition obtained by dispersing an electrode active material and a binder composition containing a binder in a dispersion medium on a current collector and drying it. Is done.

  Therefore, in recent years, attempts have been made to improve the adhesive layer provided between the electrode and the separator and the binder used to form the electrode mixture layer in order to achieve further performance improvement of the secondary battery. Yes.

  For example, Patent Document 1 has a core-shell structure including a core portion containing a methacrylic acid ester monomer and an ethylenically unsaturated carboxylic acid monomer, and a shell portion that partially covers the outer surface of the core portion. A technique for using a particulate polymer for forming an adhesive layer on the separator side for a lithium ion secondary battery is disclosed. In Patent Document 1, a styrene-butadiene copolymer is used as a binder contained in the negative electrode mixture layer that faces and contacts the adhesive layer. And in the technique of patent document 1, by providing the said contact bonding layer between a negative electrode and a separator, the adhesiveness between the electrode and separator in electrolyte solution was improved, and it was excellent in the low temperature output characteristic and the high temperature cycling characteristic The production of lithium ion secondary batteries is realized.

International Publication No. 2015/005145

  Here, in order to achieve further improvement in performance of the secondary battery, it is required to further improve the adhesion between the electrode and the separator. In the lithium ion secondary battery described in Patent Document 1, the electrode, the separator, etc. There was room for further improvement in the adhesion between the battery members.

  Therefore, an object of the present invention is to provide a non-aqueous secondary battery having high adhesion between battery members such as electrodes and separators and excellent battery performance such as cycle characteristics and output characteristics.

  The present inventor has intensively studied for the purpose of solving the above problems. And this inventor has favorable adhesiveness between a negative electrode and a separator by combining the adhesive layer provided between a negative electrode and a separator, and the binder used for formation of a negative electrode, respectively using a predetermined polymer. I found out that Specifically, by using a particulate polymer having a predetermined glass transition temperature for the formation of the adhesive layer, and using a predetermined amount of two predetermined monomer units for the binder contained in the negative electrode, It was confirmed that good adhesiveness was obtained between the battery members. And this inventor is excellent in the non-aqueous secondary battery manufactured by arrange | positioning the negative electrode containing the said binder, the said contact bonding layer, and a separator so that the said contact bonding layer exists in a predetermined position. The present inventors have found that battery performance such as cycle characteristics and output characteristics can be exhibited.

That is, this invention aims at solving the said subject advantageously, The non-aqueous secondary battery of this invention is equipped with a positive electrode, a negative electrode, a separator, electrolyte solution, and an adhesive layer, The said negative electrode is A negative electrode active material, a (meth) acrylic acid ester monomer unit of 70% by mass to 95% by mass and an ethylenically unsaturated carboxylic acid monomer unit of 1% by mass to 5% by mass. The adhesive layer is disposed between the negative electrode and the separator, and includes a particulate polymer having a glass transition temperature of 110 ° C. or lower. Thus, a negative electrode including a binder prepared using a predetermined amount of monomer units having a predetermined content ratio, and an adhesive layer formed using a particulate polymer having a glass transition temperature of a predetermined value or less. If the adhesive layer is used and disposed so as to be positioned between the negative electrode and the separator, the adhesion between the electrode and the separator can be improved. In addition, battery performance such as cycle characteristics and output characteristics of the produced non-aqueous secondary battery can be made excellent.
In the present invention, “(meth) acryl” means acryl and / or methacryl.
In the present invention, the “glass transition temperature” can be determined from a differential scanning calorimetry (DSC) curve obtained using a differential thermal analysis measurement apparatus (reference material: aluminum). It can be measured using the measurement method described in the examples of the document.
Furthermore, in the present invention, “content ratio of (meth) acrylic acid ester monomer unit” and “content ratio of ethylenically unsaturated carboxylic acid monomer unit” in the binder for negative electrode are ¹ H-NMR. It can measure using nuclear magnetic resonance (NMR) methods, such as.

  And it is preferable that the glass transition temperature of the said particulate polymer is 10 degreeC or more in the non-aqueous secondary battery of this invention. Thus, if the glass transition temperature of the particulate polymer used for forming the adhesive layer is 10 ° C. or higher, the strength as the particulate polymer is moderately increased, and the adhesion between the electrode and the separator is further enhanced. Because it can. As a result, the cycle characteristics of the non-aqueous secondary battery to be manufactured can be further improved.

  Here, the adhesive layer contains 70% by mass to 95% by mass of (meth) acrylic acid ester monomer units and 1% by mass to 5% by mass of ethylenically unsaturated carboxylic acid monomer units. It is preferable that the binder for layers is further included. If the adhesive layer further includes a binder for the adhesive layer in addition to the above particulate polymer, the adhesion of the battery member via the adhesive layer is further improved, and the secondary battery including the adhesive layer is provided. This is because the output characteristics can be further improved.

The negative electrode binder A preferably has a tetrahydrofuran (THF) insoluble content of 70% by mass or more and 95% by mass or less. As described above, when the THF-insoluble fraction in the negative electrode binder A is within the above range, the increase in battery resistance due to the elution of the negative electrode binder component into the electrolyte in the battery is suppressed. This is because the cycle characteristics can be further improved.
In the present invention, the “THF insoluble fraction” can be measured using the measuring method described in the examples of the present specification.

  Furthermore, it is preferable that the content rate of the said binder material A for negative electrodes is 0.01 mass part or more and 1.0 mass part or less with respect to 100 mass parts of said negative electrode active materials. By setting the content ratio of the negative electrode binder A in the negative electrode in the above range, the negative electrode active material, current collector, and battery member (electrode, separator) of the negative electrode binder including the negative electrode binder A This is because the adhesion property to the secondary battery can be further improved, and the cycle characteristics of the secondary battery can be further improved.

  And it is preferable that the non-aqueous secondary battery of this invention is a winding type or a laminated type. This is because if the wound type or the laminated type is used, a secondary battery excellent in output characteristics and cycle characteristics can be easily manufactured while sufficiently exhibiting high adhesiveness between battery members.

  ADVANTAGE OF THE INVENTION According to this invention, the non-aqueous secondary battery which has high adhesiveness between battery members, such as an electrode and a separator, and is excellent in battery performance, such as cycling characteristics and output characteristics, can be provided.

  Hereinafter, embodiments of the present invention will be described in detail.

(Non-aqueous secondary battery)
The non-aqueous secondary battery of the present invention includes a positive electrode, a negative electrode, a separator, an electrolytic solution, and an adhesive layer, and an adhesive layer containing a particulate polymer having a glass transition temperature of 110 ° C. or less is interposed between the negative electrode and the separator. It is characterized by being. The non-aqueous secondary battery of the present invention uses the negative electrode binder A containing a predetermined amount of (meth) acrylic acid ester monomer units and a predetermined amount of ethylenically unsaturated carboxylic acid monomer units. It is characterized by comprising the negative electrode formed in this way.
And since the non-aqueous secondary battery of this invention is equipped with the above-mentioned negative electrode and adhesive layer, the adhesiveness between battery members, such as a negative electrode and a separator, is high, and can exhibit the outstanding output characteristic and cycling characteristics. it can.
In addition, the contact bonding layer with which the non-aqueous secondary battery of this invention is provided can be suitably formed on a separator. Moreover, although the case where a secondary battery is a lithium ion secondary battery is demonstrated as an example below, this invention is not limited to the following example.

<Negative electrode>
The negative electrode included in the nonaqueous secondary battery of the present invention needs to include at least a negative electrode active material and a negative electrode binder A containing a predetermined amount of a predetermined monomer unit. Specifically, the negative electrode includes a negative electrode active material, a (meth) acrylic acid ester monomer unit of 70% by mass to 95% by mass, and an ethylenically unsaturated carboxylic acid monomer unit of 1% by mass to 5% by mass. It is necessary to contain the binder A for negative electrodes contained in% or less.
Here, the negative electrode usually includes a current collector and a negative electrode mixture layer formed on the current collector. The negative electrode mixture layer is not particularly limited. For example, a negative electrode slurry composition obtained by dispersing a negative electrode active material and a negative electrode binder containing the negative electrode binder A in a solvent. Can be formed on a current collector by coating and drying.
And since the negative electrode with which the non-aqueous secondary battery of this invention is formed using the said binder B for negative electrodes, negative electrode active materials, a negative electrode active material, a collector, and a negative electrode and a negative electrode are touched. High adhesion (peel strength) is exhibited between the obtained battery members (adhesive layer, separator, etc.).

<< Negative electrode active material >>
The negative electrode active material is a material that transfers electrons at the electrode of the secondary battery. And as a negative electrode active material for lithium ion secondary batteries, the substance which can occlude and discharge | release lithium is used normally. In addition, specific examples of the negative electrode active material include, but are not limited to, a carbon-based negative electrode active material, a metal-based negative electrode active material, and a negative electrode active material obtained by combining these materials.

Examples of the carbonaceous material include graphitizable carbon and non-graphitizable carbon having a structure close to an amorphous structure typified by glassy carbon.
Here, as the graphitizable carbon, for example, a carbon material using tar pitch obtained from petroleum or coal as a raw material can be mentioned. Specific examples include coke, mesocarbon microbeads (MCMB), mesophase pitch carbon fibers, pyrolytic vapor grown carbon fibers, and the like.
In addition, examples of the non-graphitizable carbon include a phenol resin fired body, polyacrylonitrile-based carbon fiber, pseudo-isotropic carbon, furfuryl alcohol resin fired body (PFA), and hard carbon.

Furthermore, examples of the graphite material include natural graphite and artificial graphite.
Here, as the artificial graphite, for example, artificial graphite obtained by heat-treating carbon containing graphitizable carbon mainly at 2800 ° C. or higher, graphitized MCMB heat-treated at 2000 ° C. or higher, and mesophase pitch-based carbon fiber at 2000 ° C. Examples thereof include graphitized mesophase pitch-based carbon fibers that have been heat-treated.

  Further, the metal-based negative electrode active material is an active material containing a metal, and usually includes an element capable of inserting lithium in the structure, and the theoretical electric capacity per unit mass when lithium is inserted is 500 mAh / The active material which is more than g. Examples of the metal active material include lithium metal and a single metal capable of forming a lithium alloy (for example, Ag, Al, Ba, Bi, Cu, Ga, Ge, In, Ni, P, Pb, Sb, Si, Sn). , Sr, Zn, Ti, etc.) and alloys thereof, and oxides, sulfides, nitrides, silicides, carbides, phosphides, and the like thereof. Among these, as the metal-based negative electrode active material, an active material containing silicon (silicon-based negative electrode active material) is preferable. This is because the capacity of the lithium ion secondary battery can be increased by using the silicon-based negative electrode active material.

Examples of silicon-based negative electrode active materials include silicon (Si), alloys containing silicon, SiO, SiO _x , and a composite of a Si-containing material obtained by coating or combining a Si-containing material with conductive carbon and conductive carbon. Etc. In addition, these silicon type negative electrode active materials may be used individually by 1 type, and may be used in combination of 2 types.
Among these, as the negative electrode active material, a carbon-based active material is preferable, a graphite material is more preferable, and artificial graphite is more preferable.

<< Binder for negative electrode >>
The binder for a negative electrode is a component that can hold a component included in the negative electrode mixture layer such as a negative electrode active material so as not to be detached from the negative electrode mixture layer. Moreover, the binder for negative electrodes is a component which can adhere | attach a collector and a negative electrode composite material layer with favorable peel strength, and can improve the adhesiveness and adhesiveness of an electrode.
Here, the negative electrode with which the non-aqueous secondary battery of this invention is provided needs to contain the binder A for negative electrodes at least as a binder for negative electrodes. That is, the negative electrode may include only the negative electrode binder A, may further include other negative electrode binders other than the negative electrode binder A, and may further include other negative electrode binders. preferable.

[Binder A for Negative Electrode]
The negative electrode binder A contains (meth) acrylic acid ester monomer units in an amount of 70% by mass to 95% by mass and ethylenically unsaturated carboxylic acid monomer units in an amount of 1% by mass to 5% by mass. Is not particularly limited. That is, the negative electrode binder A may contain only the predetermined amount of the (meth) acrylic acid ester monomer unit and the ethylenically unsaturated carboxylic acid monomer unit, or the (meth) acrylic acid ester unit. Other monomer units other than the monomer unit and the ethylenically unsaturated carboxylic acid monomer unit may be further contained.

[[(Meth) acrylic acid ester monomer unit]]
A (meth) acrylic acid ester monomer unit is a structural unit having a structure formed by polymerizing a (meth) acrylic acid ester monomer.

-Content-
And content of the (meth) acrylic acid ester monomer unit in the binder A for negative electrodes needs to be 70 to 95 mass%. Further, the content of the (meth) acrylate monomer unit in the negative electrode binder A is preferably 75% by mass or more, more preferably 80% by mass or more, and 94.5% by mass or less. Preferably, it is 94 mass% or less. If the negative electrode binder A contains 70% by mass or more of a (meth) acrylic acid ester monomer unit, the negative electrode binder A has increased flexibility and is formed using the negative electrode binder A. The adhesion between the negative electrode mixture layer and the current collector and the adhesion between the produced negative electrode and the battery member in contact with the negative electrode are improved. As a result, good cycle characteristics can be exhibited in the manufactured secondary battery. Further, if the (meth) acrylic acid ester monomer unit in the negative electrode binder A is 95% by mass or less, the negative electrode binder component is prevented from eluting in the electrolyte in the battery, and The output characteristics of the secondary battery can be further improved.

−Type−
Here, examples of the (meth) acrylate monomer that can form a (meth) acrylate monomer unit include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, and Acrylic acid alkyl esters such as butyl acrylate such as t-butyl acrylate, octyl acrylate such as pentyl acrylate, hexyl acrylate, heptyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, lauryl acrylate, n-tetradecyl acrylate, stearyl acrylate And methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate And butyl methacrylate such as tert-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate such as 2-ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, lauryl methacrylate, n-tetradecyl methacrylate, methacrylic acid such as stearyl methacrylate Examples thereof include alkyl esters. Of these, alkyl acrylates are preferred, butyl acrylate and 2-ethylhexyl acrylate are more preferred, and butyl acrylate is even more preferred. A (meth) acrylic acid ester monomer may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios.

[[Ethylenically unsaturated carboxylic acid monomer unit]]
An ethylenically unsaturated carboxylic acid monomer unit is a structural unit having a structure formed by polymerizing an ethylenically unsaturated carboxylic acid monomer.

-Content-
And content of the ethylenically unsaturated carboxylic acid monomer unit in the binder A for negative electrodes needs to be 1 mass% or more and 5 mass% or less. The content of the ethylenically unsaturated carboxylic acid monomer unit in the negative electrode binder A is preferably 1.3% by mass or more, more preferably 1.6% by mass or more, It is preferably 4% by mass or less, and more preferably 3% by mass or less. If the negative electrode binder A contains 1% by mass or more of an ethylenically unsaturated carboxylic acid monomer unit in addition to the above (meth) acrylic acid ester monomer unit, the polymerization reaction is stabilized. By suppressing the generation of coarse particles, the adhesion as the negative electrode can be enhanced. As a result, good cycle characteristics can be exhibited in the manufactured secondary battery. In addition, if the ethylenically unsaturated carboxylic acid monomer unit in the negative electrode binder A is 5% by mass or less, it is possible to suppress generation of a water-soluble component having an aggregating action during the polymerization. By suppressing the polymerization, the adhesion as the negative electrode can be enhanced. As a result, good cycle characteristics can be exhibited in the manufactured secondary battery.

−Type−
Here, examples of the ethylenically unsaturated carboxylic acid monomer capable of forming the ethylenically unsaturated carboxylic acid monomer unit include, for example, acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid And mono- or dicarboxylic acid (anhydride). Of these, methacrylic acid is preferred. An ethylenically unsaturated carboxylic acid monomer may be used individually by 1 type, and may combine 2 or more types by arbitrary ratios.

[[Other monomer units]]
Other monomer units other than the above-mentioned (meth) acrylic acid ester monomer units and ethylenically unsaturated carboxylic acid monomer units include (meth) acrylic acid ester monomer units and ethylenically unsaturated carboxylic acid units. There is no particular limitation as long as it is a monomer unit that can be used in combination with an acid monomer unit and can function as a binder.
Examples of other monomers that can form monomer units include, for example, vinyl cyanide monomers, unsaturated carboxylic acid amide monomers, unsaturated monomers containing hydroxyalkyl groups, and di (meta ) Acrylic acid ester monomers, aromatic vinyl monomers, aliphatic conjugated diene monomers and the like.
Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethylacrylonitrile, and the like. Among these, acrylonitrile and methacrylonitrile are preferable, and acrylonitrile is more preferable. In addition, these may be used individually by 1 type and may be used combining two or more types by arbitrary ratios.
Examples of the unsaturated carboxylic acid amide monomer include acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, N, N-dimethylacrylamide and the like. Of these, acrylamide and methacrylamide are preferable, and acrylamide and methacrylamide are more preferably used in combination. In addition, these may be used individually by 1 type and may be used combining two or more types by arbitrary ratios.
Examples of the unsaturated monomer containing a hydroxyalkyl group include β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, 3-chloro-2- Examples include hydroxypropyl methacrylate, di- (ethylene glycol) maleate, di- (ethylene glycol) itaconate, 2-hydroxyethyl maleate, bis (2-hydroxyethyl) maleate, 2-hydroxyethyl methyl fumarate and the like. In addition, these may be used individually by 1 type and may be used combining two or more types by arbitrary ratios.
Examples of the di (meth) acrylic acid ester monomer include ethylene dimethacrylate, diethylene glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, 1,3-butylene glycol diacrylate, and the like. In addition, these may be used individually by 1 type and may be used combining two or more types by arbitrary ratios.
The aromatic vinyl monomer is not particularly limited, and examples thereof include styrene, α-methylstyrene, vinyl toluene, and divinyl benzene. In addition, an aromatic vinyl monomer may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios.
Further, the aliphatic conjugated diene monomer is not particularly limited, and is 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-chloro. -1,3-butadiene, substituted linear conjugated pentadienes, substituted and side chain conjugated hexadienes, and the like. In addition, an aliphatic conjugated diene monomer may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios.

[[Polymerization method]]
The method for polymerizing the above-described monomer used for the negative electrode binder A is not particularly limited, and for example, any method such as a solution polymerization method, a suspension polymerization method, a bulk polymerization method, and an emulsion polymerization method is used. May be. As the polymerization reaction, addition polymerization such as ionic polymerization, radical polymerization, and living radical polymerization can be used. And as an emulsifier, a dispersing agent, a polymerization initiator, a chain transfer agent and the like used for polymerization, those generally used can be used, and the amount used can also be a commonly used amount.

  For example, the emulsifier that can be used for the preparation of the binder A for negative electrode is not particularly limited, and known emulsifiers such as an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphoteric interface. Any of the activators may be used. Specific examples of anionic surfactants include sodium dodecyl sulfate such as sodium lauryl sulfate, ammonium dodecyl sulfate such as ammonium lauryl sulfate, sodium octyl sulfate, sodium decyl sulfate, sodium tetradecyl sulfate, sodium hexadecyl sulfate, and sodium octadecyl sulfate. Ester salts; sodium dodecyl diphenyl ether disulfonate, sodium succinate dialkyl ester, sodium dodecyl benzene sulfonate such as sodium lauryl benzene sulfonate, alkyl benzene sulfonate such as sodium hexadecyl benzene sulfonate; dodecyl sulfonic acid such as sodium lauryl sulfonate Sodium, sodium tetradecyl sulfonate Aliphatic sulfonates such as arm; and the like, may be a so-called reactive emulsifier having an unsaturated bond. Among these, it is preferable to use sodium lauryl sulfate. One of these may be used alone, or two or more of these may be used in combination at any ratio.

  The dispersant is not particularly limited, and known dispersants such as sodium alkylbenzene sulfonate such as sodium dodecylbenzene sulfonate can be used. A dispersing agent may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios.

  Examples of the polymerization initiator include known polymerization initiators such as sodium persulfate, ammonium persulfate, and potassium persulfate. Among these, it is preferable to use ammonium persulfate. One of these may be used alone, or two or more of these may be used in combination at any ratio.

  The chain transfer agent is not particularly limited, and examples thereof include alkyl mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, t-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-stearyl mercaptan; Xanthogen compounds such as xanthogen disulfide and diisopropylxanthogen disulfide; thiuram compounds such as terpinolene, tetramethylthiuram disulfide, tetraethylthiuram disulfide and tetramethylthiuram monosulfide; 2,6-di-t-butyl-4-methylphenol Phenolic compounds such as styrenated phenols; allyl compounds such as allyl alcohol; halogenated hydrocarbon compounds such as dichloromethane, dibromomethane, carbon tetrabromide ; Thioglycolic acid, thiomalate, 2-ethylhexyl thioglycolate, diphenylethylene, etc. α- methylstyrene dimer. Among these, from the viewpoint of suppressing side reactions, alkyl mercaptans are preferable, and t-dodecyl mercaptan is more preferable. These may be used alone or in combination of two or more.

[[Properties]]
The negative electrode binder A preferably has a tetrahydrofuran (THF) insoluble content of 70% by mass or more, more preferably 75% by mass or more, still more preferably 80% by mass or more, and 95% by mass. % Or less, more preferably 93% by mass or less, and still more preferably 90% by mass or less. If the THF-insoluble fraction of the negative electrode binder A is 70% by mass or more, it is possible to suppress the elution of the negative electrode binder component in the electrolytic solution in the battery and further improve the battery resistance. Because it can. In addition, if the THF-insoluble fraction of the negative electrode binder A is 95% by mass or less, the degree of swelling of the electrolyte as an electrode becomes good, and the cycle characteristics of the manufactured secondary battery can be further improved. It is.
Note that the THF-insoluble fraction of the negative electrode binder A can be adjusted by, for example, the type and amount of the monomer used for the polymerization reaction.

[Other negative electrode binders]
Here, the other negative electrode binder that can be included in the negative electrode is not particularly limited as long as it is a binder component that can be satisfactorily used in combination with the negative electrode binder A described above. Any polymer such as a polymer can be used.
Here, the conjugated diene polymer is a polymer containing a conjugated diene monomer unit. A specific example of the conjugated diene polymer is not particularly limited, and is a copolymer containing an aromatic vinyl monomer unit such as a styrene-butadiene copolymer (SBR) and an aliphatic conjugated diene monomer unit. Examples thereof include a polymer, butadiene rubber (BR), acrylic rubber (NBR) (a copolymer containing acrylonitrile units and butadiene units), and hydrides thereof. Among these, a copolymer containing an aromatic vinyl monomer unit and an aliphatic conjugated diene monomer unit such as a styrene-butadiene copolymer (SBR) is preferable. In addition, the polymer used as another binder for negative electrodes can be mix | blended in arbitrary ratios in the binder for negative electrodes.

<< Preparation of slurry composition for negative electrode >>
The slurry composition for negative electrode includes the above-described negative electrode active material, negative electrode binder A, and optionally other negative electrode binders and additives such as thickeners, water and / or organic solvents, etc. It can be prepared by dissolving or dispersing in a solvent. Specifically, by mixing each of the above components and a solvent using a mixer such as a ball mill, sand mill, bead mill, pigment disperser, crushed grinder, ultrasonic disperser, homogenizer, planetary mixer, fill mix, etc. A slurry composition for a negative electrode can be prepared.
In addition, as a solvent used for preparation of the slurry composition for negative electrodes, you may use the solvent contained in the dispersion liquid of the binder for negative electrodes mentioned above, As a thickener, a known thickener, For example, carboxymethylcellulose sodium salt can be used.

[Blending amount]
Here, for the preparation of the negative electrode slurry composition, the negative electrode binder A is preferably contained in an amount of 0.01 parts by mass to 1.0 part by mass with respect to 100 parts by mass of the negative electrode active material. Further, the content ratio of the negative electrode binder A in the negative electrode slurry composition is more preferably 0.05 parts by mass or more, further preferably 0.1 parts by mass or more, based on 100 parts by mass of the negative electrode active material. Is more preferably 8 parts by mass or less, and still more preferably 0.5 parts by mass or less. If the content ratio of the negative electrode binder A in the negative electrode slurry composition is equal to or higher than the above lower limit, the adhesion between the negative electrode active materials and between the negative electrode active material and the current collector is improved. This is because the expansion and shrinkage resistance of the negative electrode mixture layer can be improved. As a result, the cycle characteristics of the manufactured secondary battery can be further improved. Moreover, if the content rate of the binder A for negative electrodes in the slurry composition for negative electrodes is below the said upper limit, between the negative electrode produced using the said slurry composition for negative electrodes, and the battery member which touches the said negative electrode This is because the adhesiveness can be further improved and the cycle characteristics of the secondary battery can be further improved.
When other negative electrode binders are used as the negative electrode binder, the negative electrode binders (negative electrode binder A and other negative electrode binders) in the negative electrode slurry composition The ratio is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts by mass or less, with respect to 100 parts by mass of the negative electrode active material.

<< Current collector >>
Here, as the current collector, an electrically conductive and electrochemically durable material is used. Specifically, as the current collector, for example, a current collector made of a metal material such as iron, copper, aluminum, nickel, stainless steel, titanium, tantalum, gold, or platinum can be used. In addition, the said material may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios. Especially, as a collector used for preparation of a negative electrode, the thin film which consists of copper is preferable.

<< Method for Forming Negative Electrode Composite Layer >>
The negative electrode mixture layer includes, for example, a step of applying the above-described negative electrode slurry composition on the current collector (application step) and a step of drying the negative electrode slurry composition applied on the current collector (drying step). ).

[Coating process]
It does not specifically limit as a method of apply | coating the said slurry composition for negative electrodes on a collector, A well-known method can be used. Specifically, as a coating method, a doctor blade method, a dip method, a reverse roll method, a direct roll method, a gravure method, an extrusion method, a brush coating method, or the like can be used. At this time, the slurry composition for negative electrode may be applied only to one side of the current collector, or may be applied to both sides. The thickness of the slurry film on the current collector after coating and before drying can be appropriately set according to the thickness of the negative electrode mixture layer obtained by drying.

[Drying process]
The method for drying the negative electrode slurry composition on the current collector is not particularly limited, and a known method can be used, for example, a drying method using hot air, hot air, low-humidity air, vacuum drying method, infrared ray or electron beam. The drying method by irradiation etc. is mentioned. Thus, by drying the negative electrode slurry composition on the current collector, a negative electrode mixture layer is formed on the current collector, and a negative electrode for a secondary battery comprising the current collector and the negative electrode mixture layer is formed. Can be obtained.

  Note that after the drying step, the negative electrode mixture layer may be subjected to pressure treatment using a die press or a roll press. By the pressure treatment, the adhesion between the negative electrode mixture layer and the current collector can be improved. Moreover, when a negative electrode compound material layer contains a curable polymer, it is preferable to harden the said polymer after formation of a negative electrode compound material layer.

<Positive electrode>
A known positive electrode can be used as the positive electrode. Specifically, the positive electrode is not particularly limited, and a positive electrode having a current collector and a positive electrode mixture layer formed on the current collector can be used. The positive electrode mixture layer is usually formed using a positive electrode slurry composition containing a positive electrode active material, a conductive material, and a binder.
Here, known materials can be used for the current collector, the conductive material and the binder in the positive electrode mixture layer, and for example, those described in JP2013-145663A can be used. In addition, the method for forming the positive electrode mixture layer on the current collector is not particularly limited, and examples thereof include the same method as the method for forming the negative electrode mixture layer described above.

Further, the positive electrode active material is not particularly limited, and lithium-containing cobalt oxide (LiCoO ₂ ), lithium manganate (LiMn ₂ O ₄ ), lithium-containing nickel oxide (LiNiO ₂ ), Co-Ni-Mn lithium-containing composite oxide (Li (Co Mn Ni) O 2), lithium-containing composite oxide of Ni-Mn-Al, lithium-containing composite oxide of Ni-Co-Al, olivine-type phosphate Lithium represented by lithium iron (LiFePO ₄ ), olivine-type lithium manganese phosphate (LiMnPO ₄ ), Li ₂ MnO ₃ —LiNiO ₂ solid solution, Li _{1 + x} Mn _2−x O ₄ (0 <X <2) Examples include known positive electrode active materials such as excess spinel compounds, Li [Ni _0.17 Li _0.2 Co _0.07 Mn _0.56 ] O ₂ , LiNi _0.5 Mn _1.5 O ₄ .
In addition, the compounding quantity and particle diameter of a positive electrode active material are not specifically limited, It can be made to be the same as that of the positive electrode active material used conventionally.

<Adhesive layer>
The adhesive layer provided in the non-aqueous secondary battery of the present invention needs to be disposed between the negative electrode and the separator, and is preferably formed on the separator. Moreover, the adhesive layer with which the non-aqueous secondary battery of this invention is provided contains the particulate polymer whose glass transition temperature is 110 degrees C or less.
And since the contact bonding layer with which the non-aqueous secondary battery of this invention is equipped contains the said predetermined particulate polymer, the negative electrode and separator which face each other through the said contact bonding layer can be adhere | attached favorably. Therefore, the non-aqueous secondary battery including the adhesive layer can achieve both good output characteristics (particularly low-temperature output characteristics) and good cycle characteristics (particularly high-temperature cycle characteristics).

  Moreover, the adhesive layer with which the non-aqueous secondary battery of this invention is provided contains the said predetermined particulate polymer at least, and may further further contain the binder for adhesive layers. That is, the adhesive layer may include only the particulate polymer, or may include the particulate polymer and the adhesive layer binder. Especially, it is preferable that an contact bonding layer contains both a particulate polymer and the binder for contact bonding layers.

<< Particulate polymer >>
[Properties]
Here, the particulate polymer needs to have a glass transition temperature of 110 ° C. or lower. The glass transition temperature of the particulate polymer is preferably 90 ° C. or lower, more preferably 70 ° C. or lower, preferably 10 ° C. or higher, more preferably 30 ° C. or higher, and still more preferably 40 ° C. or higher. If the glass transition temperature of the particulate polymer is 110 ° C. or less, the adhesive layer containing the particulate polymer can be given sufficient flexibility, and the negative electrode and the separator facing each other can be satisfactorily bonded via the adhesive layer. it can. As a result, good cycle characteristics are exhibited in the manufactured secondary battery. Further, if the glass transition temperature of the particulate polymer is 10 ° C. or more, the strength of the particulate polymer is sufficient, and a negative electrode and a separator positioned so as to sandwich the adhesive layer containing the particulate polymer, Can be adhered satisfactorily. Therefore, the cycle characteristics of the secondary battery can be further improved.
In addition, when a particulate polymer has the core-shell structure mentioned later, at least one of the core part and shell part which comprises the said core-shell structure should just satisfy | fill the glass transition temperature of the predetermined range mentioned above.

Moreover, it is preferable that the volume average particle diameter of a particulate polymer is 0.05 micrometer or more and 0.7 micrometer or less. If the volume average particle diameter of the particulate polymer is 0.05 μm or more, an increase in battery resistance can be suppressed, and if the volume average particle diameter of the particulate polymer is 0.7 μm or less, the particulate weight This is because the adhesive strength of the coalescence can be maintained.
In the present invention, the “volume average particle diameter” of the particulate polymer is 50% of the cumulative volume calculated from the small diameter side in the particle diameter distribution measured wet using a laser diffraction particle diameter distribution measuring device. The particle diameter (μm) can be obtained.

[Construction]
Further, the particulate polymer is not particularly limited as long as the glass transition temperature is within the above-described range. For example, individual polymers having a particle shape may exist individually, and the particle shape may be changed. The individual polymers may be present in contact with each other, or the individual polymers having a particle shape may be present in a composite form.
Examples of the case where the individual particles are present in contact or complex include, for example, a core portion having a particle shape and a shell portion partially covering the outer surface of the core portion and having a particle shape itself. The core shell structure provided may be formed.
The particulate polymer is usually present in the form of particles in the negative electrode slurry composition. The particulate polymer is usually present in the form of particles even in the formed adhesive layer, but may be in any other shape.

-Core shell structure-
In the core-shell structure, the core part is a part inside the shell part. The shell part is usually the outermost part of the particulate polymer. The form of the shell part is not particularly limited, but the shell part is preferably composed of polymer particles. When the shell part is constituted by polymer particles, a plurality of particles constituting the shell part may overlap in the radial direction of the particulate polymer. However, in the radial direction of the particulate polymer, it is preferable that the particles constituting the shell portion do not overlap each other and the particles of the polymer constitute the shell portion as a single layer.
The particulate polymer preferably has a core-shell structure in which the core part is partially covered with the shell part. This is because, when the particulate polymer has a core-shell structure, when the adhesive layer containing the particulate polymer is used, the opposing negative electrode and separator are more favorably bonded via the adhesive layer. . Accordingly, a secondary battery including the adhesive layer can exhibit better output characteristics and cycle characteristics. Here, when the particulate polymer has a core-shell structure, the reason why the adhesion between the electrode members, the output characteristics, and the cycle characteristics are further improved is not clear, but is presumed to be as follows.
That is, the particulate polymer having a core-shell structure can be obtained, for example, by preparing separate components having different adhesive forces as a core part and a shell part in multiple stages. Specifically, as described later, a polymer having a relatively low viscosity and superior adhesion is first formed as a core part. Next, a polymer having a relatively high viscosity and poor adhesiveness can be prepared as a shell part by further generating the polymer so that the shell part partially covers the surface of the core part. Here, among the obtained particulate polymer having a core-shell structure, the core part that appears partially outside without being coated is, for example, good as a binder for a negative electrode through a hot press in a battery manufacturing process. Can take on the role of attaching to. Therefore, the adhesive force between the electrode members through the adhesive layer including the core portion as a constituent part of the particulate polymer is increased. The secondary battery can exhibit better cycle characteristics due to the high adhesive force. On the other hand, among the obtained particulate polymer having a core-shell structure, the shell part partially covering the core part is like a spacer with respect to the high binding force between the core part and the negative electrode binder. Can function. Therefore, the ion conductivity in the battery is kept good while maintaining a high binding force, and the battery resistance is prevented from deteriorating. Further, the secondary battery can exhibit better output characteristics due to the low battery resistance.

[composition]
Examples of the monomer used for preparing the particulate polymer are not particularly limited as long as the polymer having the predetermined glass transition temperature can be prepared. , Ethylenically unsaturated carboxylic acid monomer, vinyl cyanide monomer, unsaturated carboxylic acid amide monomer, unsaturated monomer containing hydroxyalkyl group, aromatic vinyl monomer, aliphatic Examples thereof include conjugated diene monomers.
Among them, when the particulate polymer has a core-shell structure, the monomer used for preparing the core part includes (meth) acrylic acid ester monomer, ethylenically unsaturated carboxylic acid monomer, and di ( A meth) acrylate monomer is preferred. In particular, it is more preferable to use methyl methacrylate, butyl acrylate, methacrylic acid, and ethylene dimethacrylate together.
Moreover, as a monomer used for preparation of a shell part, an aromatic vinyl monomer is preferable and it is more preferable to use styrene especially.

[Polymerization method]
The polymerization method of the particulate polymer is not particularly limited, and examples thereof include the polymerization method of the above-described negative electrode binder A.
Examples of the polymerization method for the particulate polymer having a core-shell structure include a multistage emulsion polymerization method. As the multistage emulsion polymerization method, for example, a known polymerization method described in Patent Document 1 can be used. Moreover, as the emulsifier, the dispersant, the polymerization initiator, the chain transfer agent, etc. used in the multi-stage emulsion polymerization, those commonly used can be used, and the amount used can also be the amount generally used. it can.

Specifically, as a polymerization procedure of the multi-stage emulsion polymerization method, first, a monomer and an emulsifier that form a core part are mixed in water as a solvent, and then a polymerization initiator is added, followed by emulsion polymerization. A particulate polymer constituting the part is obtained. Furthermore, a particulate polymer having a core-shell structure can be obtained by polymerizing a monomer that forms a shell portion in the presence of the particulate polymer constituting the core portion. At this time, from the viewpoint of partially covering the outer surface of the core part with the shell part, the polymer monomer of the shell part is preferably divided into a plurality of times or continuously supplied to the polymerization system. By dividing the polymer monomer of the shell part into a polymerization system or continuously supplying the polymer, the polymer constituting the shell part is formed into particles, and the particles are bonded to the core part. A shell part that partially covers the core part can be formed.
Moreover, when the monomer which forms the polymer of the shell portion is a monomer having a low affinity for the polymerization solvent, it tends to form a shell portion that partially covers the core portion. When the polymerization solvent is water, the monomer forming the polymer of the shell part preferably contains a hydrophobic monomer, and particularly preferably contains an aromatic vinyl monomer as described above.
Moreover, if the amount of the emulsifier used is reduced, there is a tendency to form a shell part that partially covers the core part. By appropriately adjusting the amount of the emulsifier, a shell part that partially covers the core part can be formed. it can.

  Here, the content ratio of the particulate polymer with respect to the total polymer content used for forming the adhesive layer is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, particularly Preferably it is 80 mass% or more, Preferably it is 99.9 mass% or less, More preferably, it is 99 mass% or less, More preferably, it is 98 mass% or less, Most preferably, it is 96 mass% or less. This is because if the content ratio of the particulate polymer is equal to or higher than the above lower limit, the adhesiveness between the battery members via the adhesive layer can be improved. Moreover, it is because the ion diffusibility inside a battery can be improved if the content rate of a particulate polymer shall be below the said upper limit.

<< Binder for adhesive layer >>
And it is preferable that an adhesive layer further contains the binder for adhesive layers in addition to the particulate polymer mentioned above. If the adhesive layer is included together with the particulate polymer and the binder for the adhesive layer, the adhesive layer and the binder for the negative electrode are better bonded to further improve the output characteristics and cycle characteristics of the manufactured secondary battery. It is because it can be made.

[composition]
Here, the binder for the adhesive layer is not particularly limited, and may contain, for example, a predetermined amount of each of a (meth) acrylic acid ester monomer unit and an ethylenically unsaturated carboxylic acid monomer unit. preferable. Moreover, the binder for adhesive layers may further contain other monomer units other than the (meth) acrylic acid ester monomer unit and the ethylenically unsaturated carboxylic acid monomer unit.
In addition, as the (meth) acrylic acid ester monomer, the ethylenically unsaturated carboxylic acid monomer, and other monomers that are preferably used for the preparation of the binder for the adhesive layer, the above-described negative electrode binder is used. The monomer similar to the material A can be mentioned. Among these, as the (meth) acrylic acid ester monomer, butyl acrylate and 2-ethylhexyl acrylate are preferable, and butyl acrylate is more preferable. As the ethylenically unsaturated carboxylic acid monomer, methacrylic acid is preferable. Furthermore, as other monomers, for example, acrylonitrile, N-methylolacrylamide, acrylamide, and ethylene dimethacrylate are preferable. One of these may be used alone, or two or more of these may be used in combination at any ratio.

[Content]
The content of the (meth) acrylic acid ester monomer unit in the binder for the adhesive layer is preferably 70% by mass or more, more preferably 75% by mass or more, still more preferably 80% by mass or more, and 95% by mass. % Or less, more preferably 94.5% by mass or less, and still more preferably 94% by mass or less. If the binder for the adhesive layer contains 70% by mass or more of a (meth) acrylic acid ester monomer unit, the flexibility of the adhesive layer is increased and the adhesion between the negative electrode and the separator via the adhesive layer is improved. Become. As a result, good cycle characteristics can be exhibited in the manufactured secondary battery. Moreover, if the (meth) acrylic acid ester monomer unit in the binder for the adhesive layer is 95% by mass or less, the binder component for the adhesive layer is prevented from eluting in the electrolyte in the battery, In addition, the output characteristics of the secondary battery can be further improved.

  The ethylenically unsaturated carboxylic acid monomer unit in the binder for the adhesive layer is preferably 1% by mass or more, more preferably 1.3% by mass or more, still more preferably 1.6% by mass or more. % By mass or less is preferable, 4% by mass or less is more preferable, and 3% by mass or less is more preferable. If the binder for the adhesive layer contains 1% by mass or more of the ethylenically unsaturated carboxylic acid monomer unit in addition to the above (meth) acrylic acid ester monomer unit, the polymerization reaction is stabilized and coarse particles By suppressing the polymerization, the adhesion between battery members can be enhanced. As a result, good cycle characteristics can be exhibited in the manufactured secondary battery. Further, if the ethylenically unsaturated carboxylic acid monomer unit in the binder for the adhesive layer is 5% by mass or less, the adhesion between the battery members can be reduced by suppressing the polymerization of coarse particles in the same manner as described above. Can be increased. As a result, good cycle characteristics can be exhibited in the manufactured secondary battery.

The reason why the adhesiveness between the battery members such as the negative electrode and the separator is further improved by including the predetermined monomer unit in the adhesive layer binder is not clear, but is presumed as follows. Is done.
That is, the negative electrode binder A contained in the negative electrode mixture layer and the adhesive layer binder contained in the adhesive layer, which are in direct contact with each other in the battery structure, have the same components, and thus the negative electrode binder. It becomes easy to integrate the adhering material A and the binder for the adhesive layer with good compatibility. As a result, the negative electrode and the separator arranged so as to sandwich the adhesive layer containing the adhesive layer binder can be bonded more firmly. And the said adhesive force becomes still stronger, when the battery member containing a negative electrode and a separator passes hot press.

  The glass transition temperature of the binder for the adhesive layer is preferably −100 ° C. or higher, more preferably −90 ° C. or higher, particularly preferably −80 ° C. or higher, preferably 0 ° C. or lower, more preferably −5. ° C or lower, particularly preferably -10 ° C or lower. This is because the adhesiveness of the adhesive layer can be improved by setting the glass transition temperature of the binder for the adhesive layer to the above lower limit value or more. Moreover, it is because the softness | flexibility of an contact bonding layer can be raised by making the glass transition temperature of the binder for contact bonding layers below into the said upper limit.

  In addition, the form of the binder for adhesive layers may be particulate or non-particulate. Among these, from the viewpoint of providing pores in the adhesive layer to increase the ion diffusibility inside the battery, the form of the binder for the adhesive layer is preferably particulate.

  Here, when the binder for the adhesive layer has a particulate form, the volume average particle diameter of the binder for the adhesive layer is preferably 0.01 μm or more, more preferably 0.02 μm or more, and particularly preferably. It is 0.05 μm or more, preferably 1 μm or less, more preferably 0.9 μm or less, and particularly preferably 0.8 μm or less. It is because the dispersibility in the slurry composition for the adhesive layers described later of the adhesive layer binder can be enhanced by setting the volume average particle diameter of the adhesive material for the adhesive layer to the above lower limit value or more. Moreover, it is because the adhesiveness of a contact bonding layer can be improved by making the volume average particle diameter of the binder for contact bonding layers below into the said upper limit.

  The content of the binder for the adhesive layer is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, preferably 50 parts by mass with respect to 100 parts by mass of the particulate polymer. Hereinafter, it is more preferably 40 parts by mass or less, particularly preferably 30 parts by mass or less. This is because the strength of the adhesive layer can be increased by setting the content of the binder for the adhesive layer to the lower limit value or more. Moreover, it is because a particulate polymer can fully promote the ion diffusibility in a battery inside by making content of the binder for adhesive layers below the said upper limit.

[Polymerization method]
The method for polymerizing the binder for the adhesive layer is not particularly limited, and examples thereof include the same polymerization method as that for the above-described binder A for negative electrode.

<< Preparation of slurry composition for adhesive layer >>
The slurry composition for the adhesive layer is obtained by dispersing the above-mentioned particulate polymer, the binder for the adhesive layer, and, if necessary, a surfactant such as ethylene oxide-propylene oxide copolymer in a solvent such as water. Can be prepared. Moreover, the dispersion method etc. can mention the dispersion method similar to the thing of the above-mentioned binder B for negative electrodes.

<< Formation of adhesive layer >>
The adhesive layer is not particularly limited, and is formed, for example, through a coating process and a drying process, in the same manner as the above-described method for forming the negative electrode mixture layer.
The adhesive layer may be formed on the negative electrode mixture layer provided in the negative electrode and / or may be formed on the separator, and is preferably formed on the separator. The adhesive layer may be formed only on one side of the negative electrode and / or the separator, or may be formed on both sides. However, when it is formed on the separator, it is preferably formed on both sides of the separator.

  Here, the thickness of the adhesive layer is preferably 0.1 μm or more, more preferably 0.2 μm or more, particularly preferably 0.5 μm or more, preferably 5 μm or less, more preferably 4 μm or less, particularly preferably 3 μm or less. It is. This is because the adhesiveness of the adhesive layer can be increased by setting the thickness of the adhesive layer to the lower limit value or more. Moreover, it is because the raise of the battery resistance resulting from an adhesive layer can be suppressed, and the cycling characteristics of a secondary battery can be prevented from falling by making the thickness of an adhesive layer below the said upper limit.

<Separator>
The separator is not particularly limited. For example, a microporous film using a polyolefin resin (polyethylene, polypropylene, polybutene, polyvinyl chloride), a polyamide such as polyethylene terephthalate, polycycloolefin, polyether sulfone, or nylon. , Microporous membranes using resins such as polyimide, polyimideamide, polyaramid, polycycloolefin, polytetrafluoroethylene, woven or non-woven fabrics using polyolefin fibers, aggregates of particles made of insulating materials, etc. It is done. Among these, the thickness of the entire separator can be reduced, thereby increasing the ratio of the electrode mixture layer in the non-aqueous secondary battery and increasing the capacity per volume, A microporous film using a polyolefin resin (polyethylene, polypropylene, polybutene, polyvinyl chloride) is preferred.
In addition, as a separator, you may use what has further the porous film containing the nonelectroconductive particle and / or the binder for porous films on the microporous film, woven fabric, or nonwoven fabric mentioned above, for example.
Here, as the non-conductive particles, it is preferable to use particles formed of an electrochemically stable material, inorganic particles may be used, organic particles may be used, inorganic particles and organic particles may be used. You may use together. Further, the binder for the porous film is not particularly limited, and for example, the same unit as the weight unit that can be used for the above-mentioned binder for the adhesive layer can be used.

<Electrolyte>
As the electrolytic solution, an organic electrolytic solution in which a supporting electrolyte is dissolved in an organic solvent is usually used. For example, when the non-aqueous secondary battery is a lithium ion secondary battery, a lithium salt is used as the supporting electrolyte. 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 F ₉ SO ₃ Li, CF ₃ COOLi, (CF ₃ CO) ₂ NLi , (CF ₃ SO ₂ ) ₂ NLi, (C ₂ F ₅ SO ₂ ) NLi, and the like. Of these, LiPF ₆ , LiClO ₄ , and CF ₃ SO ₃ Li are preferable, and LiPF ₆ is particularly preferable because it is easily dissolved in a solvent and exhibits a high degree of dissociation. In addition, electrolyte may be used individually by 1 type and may be used combining two or more types by arbitrary ratios. Usually, the lithium ion conductivity tends to increase as the supporting electrolyte having a higher degree of dissociation is used, and therefore the lithium ion conductivity can be adjusted depending on the type of the supporting electrolyte.

The organic solvent used in the electrolytic solution is not particularly limited as long as it can dissolve the supporting electrolyte. For example, dimethyl carbonate (DMC), ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC) ), Carbonates such as butylene carbonate (BC) and ethyl methyl carbonate (EMC); esters such as γ-butyrolactone and methyl formate; ethers such as 1,2-dimethoxyethane and tetrahydrofuran; including sulfolane and dimethyl sulfoxide Sulfur compounds; etc. are preferably used. Moreover, you may use the liquid mixture of these solvents. Among them, it is preferable to use carbonates because they have a high dielectric constant and a wide stable potential region, and it is more preferable to use a mixture of ethylene carbonate and ethyl methyl carbonate.
Further, known additives such as vinylene carbonate (VC), fluoroethylene carbonate (FEC), and ethyl methyl sulfone may be added to the electrolytic solution.

<Assembly of secondary battery>
The nonaqueous secondary battery of the present invention is preferably a wound type or a stacked type, and more preferably a wound type. This is because if the wound type or the laminated type is used, the negative electrode and the separator are hot-pressed well through the adhesive layer in the battery manufacturing process, so that the adhesion between the battery members can be further improved.

  Here, in the battery member such as a positive electrode and a negative electrode, a separator, and an adhesive layer provided in the nonaqueous secondary battery of the present invention, the positive electrode is usually in contact with one side of the separator and the negative electrode is in contact with the other side of the separator. Placed in. More specifically, the positive electrode mixture layer side is disposed on one side of the separator, and the negative electrode mixture layer side is disposed on the other side of the separator so as to contact the separator. In the nonaqueous secondary battery of the present invention, an adhesive layer needs to be disposed at least between the negative electrode and the separator. That is, in the nonaqueous secondary battery of the present invention, an adhesive layer may exist only between the negative electrode and the separator, and an adhesive layer may also exist between the positive electrode and the separator. More specifically, the adhesive layer may exist only between the negative electrode mixture layer and the separator, and further, the adhesive layer may also exist between the positive electrode mixture layer and the separator.

  In addition, the nonaqueous secondary battery of the present invention is not particularly limited and can be manufactured using a known assembly method. Specifically, the non-aqueous secondary battery of the present invention is placed in a battery container by, for example, winding an electrode and a separator into a battery shape as needed via an adhesive layer as described above. It can be manufactured by injecting an electrolyte into a battery container and sealing it. Here, in order to prevent an increase in internal pressure of the non-aqueous secondary battery, occurrence of overcharge / discharge, etc., an overcurrent prevention element such as a fuse or PTC element, an expanded metal, a lead plate, etc. are provided as necessary. May be. The shape of the secondary battery may be any of a coin type, a button type, a sheet type, a cylindrical type, a square type, a flat type, and the like.

EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the following description, “%” and “part” representing amounts are based on mass unless otherwise specified.
And the THF-insoluble fraction of the negative electrode binder A, the glass transition temperature of the particulate polymer contained in the adhesive layer, the adhesion between the battery members (negative electrode and separator), the low-temperature output characteristics of the secondary battery, and the high-temperature cycle The characteristics were calculated, measured and evaluated by the following methods.

<THF insoluble fraction>
The tetrahydrofuran (THF) insoluble fraction of the negative electrode binder A is the ratio (mass%) of the weight of solids insoluble in THF to the total solid weight of the polymer contained in the negative electrode binder A. Can be sought. Specifically, the aqueous dispersion A in which the negative electrode binder A is dispersed in water is dried for 3 days in an environment of 50% humidity and a temperature of 23 ° C. or more and 25 ° C. or less, and then a hot air oven is used. Then, a dried dispersion was obtained by drying in an environment of 120 ° C. for 1 hour. The obtained dried dispersion was formed into a film having a thickness of 3 ± 0.3 mm, and cut into a substantially square shape having a side of 5 mm, thereby preparing a dry film piece.
The prepared dry film piece was precisely weighed, and the weight of the obtained dry film piece was defined as W ₀ .
Next, the dried film piece was immersed and dissolved in 100 g of THF at 23 ° C. or more and 25 ° C. or less for 24 hours. The residual film piece lifted from THF was vacuum-dried at 105 ° C. for 3 hours, and the dried residual film piece was precisely weighed, and the weight of the obtained residual film piece was defined as W ₁ .
And the following formula (I):
THF insoluble fraction (%) = (W ₁ / W ₀ ) × 100 (I)
According to the calculation, the THF-insoluble fraction was calculated. The results are shown in Table 1.

<Glass transition temperature>
The glass transition temperature of the particulate polymer contained in the adhesive layer was measured using a differential thermal analyzer (manufactured by SII Nanotechnology, product name “EXSTAR DSC6220”). Specifically, 10 mg of a dried sample of the particulate polymer was placed in an aluminum pan and weighed. An empty aluminum pan was used as the reference material. The sample is put in the differential thermal analysis measuring device, measured at a temperature range of −100 ° C. to 500 ° C. (temperature increase rate 10 ° C./min) under a relative humidity of 50% at a temperature of 25 ° C. DSC) curve was obtained. In the DSC curve, the temperature corresponding to the intersection of the baseline immediately before the endothermic peak where the differential signal (DDSC) is 0.05 mW / min / mg or more and the tangent at the first inflection point after the endothermic peak. Was determined as the glass transition temperature (° C.). The results are shown in Table 1.
In addition, the glass transition temperature of the binder for adhesive layers was measured by the same method as described above except that the measurement temperature was −50 ° C. or higher.

<Adhesiveness between battery members>
The adhesion between battery members (negative electrode and separator) was measured as peel strength as follows. Specifically, the produced negative electrode and the separator on which the adhesive layer is formed are overlapped so that the negative electrode mixture layer and the adhesive layer face each other, and cut into a substantially square shape having a side of 10 mm, thereby obtaining a laminated piece. It was. The obtained laminated piece was pressed at a temperature of 70 ° C. and a pressure of 1.0 MPa for 8 seconds to obtain a test piece in which the negative electrode and the separator were integrated.
A cellophane tape was attached to the surface of the current collector with the negative electrode (current collector) side of the obtained test piece facing down. At this time, the cellophane tape defined in JIS Z1522 was used, and the cellophane tape was fixed to a horizontal test stand. And the stress when the one end by the side of a separator among test pieces was pulled and peeled in the perpendicular direction at the speed | rate of 50 mm / min was measured. The same measurement was performed three times, and the average value of the measurement results was defined as peel strength, and the adhesiveness was determined according to the following criteria. It shows that the adhesiveness between a negative electrode and a separator is so high that peel strength is large. The results are shown in Table 1.
A: Peel strength is 10 N / m or more B: Peel strength is 5 N / m or more and less than 10 N / m C: Peel strength is 3 N / m or more and less than 5 N / m D: Peel strength is less than 3 N / m

<Low temperature output characteristics>
The manufactured 800 mAh wound type lithium ion secondary battery was allowed to stand for 24 hours in an environment of 25 ° C. Thereafter, in a 25 ° C. environment, a charging operation was performed for 5 hours at a charging rate of 0.1 C, and the voltage V ₀ after the charging operation was measured.
Next, a discharge operation was performed at a discharge rate of 1 C in an environment of −10 ° C., and the voltage V ₁ after 15 seconds from the start of discharge was measured. Then, the voltage change [Delta] V, was calculated by a formula: ΔV = V ₀ -V _1. It shows that the low temperature output characteristic of a secondary battery is excellent, so that the value of the said voltage change (DELTA) V is small. The results are shown in Table 1.
A: Voltage change ΔV is less than 350 mV B: Voltage change ΔV is 350 mV or more and less than 500 mV C: Voltage change ΔV is 500 mV or more and less than 650 mV D: Voltage change ΔV is 650 mV or more

<High temperature cycle characteristics>
The manufactured 800 mAh wound type lithium ion secondary battery was allowed to stand for 24 hours in an environment of 25 ° C. Thereafter, the battery was charged to 4.35 V at a rate of 0.1 C in an environment of 25 ° C. Next, the initial charge / discharge operation was performed by discharging the charged secondary battery to 2.75 V at a rate of 0.1 C. The capacity of the secondary battery after the initial charge and discharge was measured as the initial capacity C _0.
Subsequently, charging and discharging were repeated 1000 cycles under the same conditions as described above in a 60 ° C. environment. The capacity of the secondary battery through the 1000 cycles were measured as C _1. The capacity retention ratio ΔC was calculated by ΔC = C ₁ / C ₀ × 100 (%). It shows that a lithium ion secondary battery is excellent in high temperature cycling characteristics, and a secondary battery has a long lifetime, so that the value of the said capacity maintenance factor (DELTA) C is high. The results are shown in Table 1.
A: Capacity maintenance ratio ΔC is 84% or more B: Capacity maintenance ratio ΔC is 80% or more and less than 84% C: Capacity maintenance ratio ΔC is 75% or more and less than 80% D: Capacity maintenance ratio ΔC is less than 75%

Example 1
<Production of negative electrode>
<< Preparation of binder for negative electrode >>
[Binder A for Negative Electrode]
In a reactor equipped with a stirrer, 70 parts of ion-exchanged water, 0.15 part of sodium lauryl sulfate (product name “Emal 2F” manufactured by Kao Chemical Co., Ltd.) as an emulsifier, and 0.5 part of ammonium persulfate as a polymerization initiator Each was supplied, the gas phase was replaced with nitrogen gas, and the temperature was raised to 60 ° C.
Meanwhile, in a separate container, 50 parts of ion-exchanged water, 0.5 part of sodium dodecylbenzenesulfonate as a dispersant, 93 parts of butyl acrylate as a (meth) acrylic acid ester monomer, an ethylenically unsaturated carboxylic acid monomer As a polymerizable monomer, 2 parts of methacrylic acid and 2 parts of acrylonitrile, 1 part of N-methylolacrylamide, and 2 parts of acrylamide were supplied and mixed to obtain a monomer mixture. The monomer mixture was continuously added to the reactor over 4 hours for polymerization. During the addition of the monomer mixture, the polymerization reaction was continued at a temperature of 60 ° C. After completion of the addition, the polymerization reaction was completed by further stirring for 3 hours at a temperature of 70 ° C., and as the negative electrode binder A, a (meth) acrylic acid ester monomer unit and an ethylenically unsaturated carboxylic acid monomer unit were used. An aqueous dispersion A containing an acrylic polymer containing was prepared. The obtained acrylic polymer had a glass transition temperature of −45 ° C. and a volume average particle diameter D50 of 0.36 μm.
And the THF insoluble fraction was measured by the above-mentioned method using the acrylic polymer as the obtained binder A for negative electrodes. The results are shown in Table 1.

[Binder B for Negative Electrode]
61.5 parts of styrene as an aromatic vinyl monomer, 35 parts of 1,3-butadiene as an aliphatic conjugated diene monomer, 3.5 parts of itaconic acid as an ethylenically unsaturated carboxylic acid monomer, as a chain transfer agent A mixed liquid of 0.25 part of tert-dodecyl mercaptan and 0.35 part of sodium lauryl sulfate as an emulsifier was added from the container containing the mixed liquid to another pressure resistant container. Simultaneously with the addition, 1 part of potassium persulfate as a polymerization initiator was added to the pressure vessel to initiate the polymerization reaction. The polymerization reaction temperature was maintained at 75 ° C.
Five and a half hours after the start of the polymerization, the addition of the whole amount of the monomer was completed, and then the temperature was further increased to 85 ° C. and the polymerization reaction was continued for 6 hours.
When the polymerization conversion rate reached 97%, the reaction was stopped by cooling to obtain a mixture containing a particulate polymer. A 5% aqueous sodium hydroxide solution was added to the resulting mixture containing the particulate polymer to adjust the mixture to pH 8. Then, the unreacted monomer was removed by heating under reduced pressure. Furthermore, it cooled after that and the aqueous dispersion B (solid content concentration: 40%) containing the styrene-butadiene copolymer was obtained as the binder B for negative electrodes which is another binder for negative electrodes.

<< Preparation of slurry composition for negative electrode >>
100% of artificial graphite (volume average particle diameter: 15.6 μm) as the negative electrode active material and 2% aqueous solution of carboxymethylcellulose sodium salt (product name “MAC350HC” manufactured by Nippon Paper Industries Co., Ltd.) as the thickener After mixing 1 part and adding ion exchange water and adjusting solid content concentration to 68%, it mixed for 60 minutes under the temperature of 25 degreeC, and obtained the liquid mixture. After adding ion exchange water further to the obtained liquid mixture and adjusting solid content concentration to 62%, mixing was further added for 15 minutes under the temperature of 25 degreeC. As the negative electrode binder obtained above, 0.20 part of the aqueous dispersion A corresponding to the solid content and 1.30 parts of the aqueous dispersion B corresponding to the solid content are added to the mixed liquid, and ion-exchanged water is further added. Was added to adjust the final solid content concentration to 52%, and further mixing was continued for 10 minutes to obtain a polymer mixture. And the slurry composition for negative electrodes was obtained by carrying out the defoaming process of the said polymer liquid mixture under reduced pressure.

<< Formation of Negative Electrode Composite Layer >>
The negative electrode slurry composition obtained above was applied on a copper foil (thickness 20 μm) as a current collector using a comma coater so that the film thickness after drying was about 150 μm. Next, the negative electrode slurry composition was dried by conveying the copper foil coated with the negative electrode slurry composition through an oven at a temperature of 60 ° C. at a rate of 0.5 m / min for 2 minutes. . Thereafter, the copper foil coated with the negative electrode slurry composition was further heat-treated at a temperature of 120 ° C. for 2 minutes to obtain a negative electrode raw material before pressing. And the negative electrode raw material before the said press was rolled by the roll press, and the negative electrode after the press whose thickness of a negative electrode compound-material layer is 80 micrometers was obtained.

<Preparation of positive electrode>
<< Preparation of slurry composition for positive electrode >>
100 parts of LiCoO ₂ (volume average particle diameter: 12.0 μm) as the positive electrode active material, ₂ parts of acetylene black (manufactured by Denki Kagaku Kogyo Co., Ltd., product name “HS-100”) as the conductive material, and binder for the positive electrode As a mixed liquid, polyvinylidene fluoride (product name “# 7208”, manufactured by Kureha Co., Ltd.) was mixed in an amount of 2 parts corresponding to the solid content, and N-methylpyrrolidone was added to the mixture as a solvent to adjust the total solid content concentration to 70%. Got. And the slurry composition for positive electrodes was obtained by mixing the said liquid mixture with a planetary mixer.

<< Formation of Positive Electrode Mixture Layer >>
The positive electrode slurry composition obtained above was applied onto an aluminum foil (thickness 20 μm) as a current collector using a comma coater so that the film thickness after drying was about 150 μm. Next, the positive electrode slurry composition was dried by conveying the aluminum foil coated with the positive electrode slurry composition through an oven at a temperature of 60 ° C. at a rate of 0.5 m / min for 2 minutes. . Thereafter, the aluminum foil coated with the positive electrode slurry composition was further heat-treated at a temperature of 120 ° C. for 2 minutes to obtain a positive electrode raw material before pressing. And the positive electrode after a press was obtained by rolling the said positive electrode original fabric before a press with a roll press.

<Preparation of adhesive layer>
<< Preparation of particulate polymer for adhesive layer >>
In a 5 MPa pressure vessel with a stirrer, 65 parts of methyl methacrylate and 30 parts of butyl acrylate as the (meth) acrylic acid ester monomer used for the production of the core part, 4 parts of methacrylic acid as the ethylenically unsaturated carboxylic acid monomer, etc. 1 part of ethylene dimethacrylate as a polymerizable monomer, 1 part of sodium dodecylbenzenesulfonate as an emulsifier, 150 parts of ion-exchanged water, and 0.5 part of potassium persulfate as a polymerization initiator were sufficiently stirred. . Then, it heated to 60 degreeC and superposition | polymerization was started. By continuing the polymerization at a temperature of 60 ° C. until the polymerization conversion rate reached 96%, an aqueous dispersion containing a particulate polymer constituting the core part was obtained.
Next, the aqueous dispersion was heated to 70 ° C. The polymerization was continued at a temperature of 70 ° C. by continuously supplying 20 parts of styrene as a polymerizable monomer used for producing the shell part over 30 minutes to the aqueous dispersion. When the polymerization conversion rate reached 96%, the reaction was stopped by cooling to obtain an aqueous dispersion containing the particulate polymer used for forming the adhesive layer. When the cross section of the obtained particle polymer was observed, the shell part itself was also comprised with the particulate polymer. In addition, the volume average particle diameter D50 of the obtained particulate polymer was 0.45 μm.
And the glass transition temperature of the core part of the obtained particulate polymer was measured. The results are shown in Table 1.

<< Preparation of binder for adhesive layer >>
In a reactor equipped with a stirrer, 70 parts of ion-exchanged water, 0.15 part of sodium lauryl sulfate (product name “Emal 2F” manufactured by Kao Chemical Co., Ltd.) as an emulsifier, and 0.5 part of ammonium persulfate as a polymerization initiator Each was supplied, the gas phase was replaced with nitrogen gas, and the temperature was raised to 60 ° C.
On the other hand, in a separate container, 50 parts of ion exchange water, 0.5 part of sodium dodecylbenzenesulfonate as a dispersant, 93 parts of butyl acrylate, 2 parts of methacrylic acid, 2 parts of acrylonitrile, N- A monomer mixture was obtained by supplying and mixing 1 part of methylolacrylamide and 2 parts of acrylamide. The monomer mixture was continuously added to the reactor over 4 hours for polymerization. During the addition of the monomer mixture, the polymerization reaction was continued at a temperature of 60 ° C. After completion of the addition, the polymerization reaction was terminated by further stirring for 3 hours at a temperature of 70 ° C., and an aqueous dispersion C containing an acrylic polymer as a binder for the adhesive layer was prepared.
The obtained acrylic polymer had a glass transition temperature of −45 ° C. and a volume average particle diameter D50 of 0.36 μm.

<< Preparation of slurry composition for adhesive layer >>
100 parts of the aqueous dispersion containing the particulate polymer obtained above is equivalent to the solid content, and the aqueous dispersion C of the acrylic polymer as the binder for the adhesive layer obtained above is equivalent to the solid content. 22 parts and 2 parts of ethylene oxide-propylene oxide copolymer were added, and ion-exchanged water was further added to a solid content concentration of 20% and stirred to form an adhesive layer. A slurry composition for an adhesive layer was obtained.

<< Formation of adhesive layer >>
A polyethylene organic porous substrate (thickness: 16 μm, Gurley value: 210 s / 100 cc) was prepared as a separator substrate. The adhesive layer slurry composition obtained above was applied to both surfaces of the prepared separator substrate by a spray coating method. Next, the adhesive layer was formed on both surfaces of the separator by drying the separator coated with the slurry composition for the adhesive layer at a temperature of 50 ° C. for 1 minute. In addition, the thickness per one side of the formed adhesive layer was 1 μm. By the above-mentioned method, the separator with the adhesive layer in which the adhesive layer was formed on both sides was obtained.
And the adhesiveness between electrode members was evaluated by the above-mentioned method using the obtained negative electrode and the separator with an adhesive layer. The results are shown in Table 1.

<Manufacture of secondary batteries>
The pressed positive electrode was cut out to 49 cm × 5.0 cm. A separator with an adhesive layer cut out to 55 cm × 5.5 cm was arranged on the positive electrode mixture layer of the cut out positive electrode. Furthermore, by cutting the negative electrode after pressing into 50 cm × 5.2 cm, and arranging the cut negative electrode so that the surface of the separator that is not in contact with the positive electrode mixture layer faces the negative electrode mixture layer, A laminate having a positive electrode, a separator, and a negative electrode was obtained. Here, adhesive layers are respectively interposed between the positive electrode and the separator, and between the negative electrode and the separator. Next, the obtained laminate was wound with a winding machine to obtain a wound body having a positive electrode, a separator, and a negative electrode. Further, the wound body was pressed at a temperature of 70 ° C. and a pressure of 1.0 MPa for 8 seconds to obtain a flat body. Then, the flat body is wrapped with an aluminum wrapping case as a battery case, and an electrolytic solution (electrolyte: LiPF _{6 having} a concentration of 1 M, solvent: ethylene carbonate (EC) / diethyl carbonate (DEC) / vinylene carbonate (VC) = 68.5 / 30 / 1.5 (volume ratio)) was injected so that no air remained. Furthermore, the aluminum exterior was hermetically closed by heat-sealing the opening of the aluminum packaging material at 150 ° C., and an 800 mAh wound lithium ion secondary battery was manufactured.
And about the manufactured lithium ion secondary battery, the above-mentioned method evaluated the low temperature output characteristic and the high temperature cycling characteristic. The results are shown in Table 1.

(Example 2)
In the preparation of the binder for the negative electrode, the negative electrode was prepared in the same manner as in Example 1 except that butyl acrylate was changed to 78 parts and 15 parts of 2-ethylhexyl acrylate was added as the (meth) acrylate monomer. Binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and secondary battery Manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 3)
In the preparation of the binder for the negative electrode, the negative electrode was prepared in the same manner as in Example 1, except that butyl acrylate was changed to 71 parts and 22 parts of 2-ethylhexyl acrylate was added as the (meth) acrylic acid ester monomer. Binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and secondary battery Manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

Example 4
In the preparation of the binder for the negative electrode, except that butyl acrylate as a (meth) acrylic acid ester monomer was changed to 94.8 parts and acrylonitrile as another polymerizable monomer was changed to 0.2 parts. In the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer slurry composition, the adhesive Layer, separator with adhesive layer, and secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 5)
In preparing the negative electrode binder, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 3.5 parts, and acrylonitrile as the other polymerizable monomer was changed to 0.5 parts. In the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer slurry composition, the adhesive Layer, separator with adhesive layer, and secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 6)
In preparing the negative electrode binder, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 4.5 parts, and as other polymerizable monomer, 0.5 part of acrylonitrile and 1 part of acrylamide were used. The negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, and the adhesive layer, except for changing to the part A slurry composition, an adhesive layer, a separator with an adhesive layer, and a secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 7)
In preparing the negative electrode binder, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 1.2 parts, and acrylonitrile as the other polymerizable monomer was changed to 2.8 parts In the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer slurry composition, the adhesive Layer, separator with adhesive layer, and secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 8)
In the preparation of the negative electrode binder, as other polymerizable monomer, N-methylolacrylamide was changed to 0.5 part, and acrylonitrile was changed to 2.5 parts. , Negative electrode binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and two A secondary battery was manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

Example 9
In the preparation of the binder for the negative electrode, the same procedure as in Example 1 was performed except that N-methylolacrylamide was changed to 0.3 part and acrylonitrile was changed to 2.7 parts as other polymerizable monomers. , Negative electrode binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and two A secondary battery was manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 10)
In the preparation of the negative electrode binder, as other polymerizable monomer, N-methylolacrylamide was changed to 1.5 parts, and acrylonitrile was changed to 1.5 parts. , Negative electrode binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and two A secondary battery was manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 11)
In the preparation of the negative electrode slurry composition, 0.08 part of the aqueous dispersion A containing the acrylic polymer as a binder for the negative electrode and 0.02 part of the aqueous dispersion B corresponding to the solid part and 1.42 parts of the aqueous dispersion B, respectively. The negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, and the adhesive layer slurry, except for changing to A composition, an adhesive layer, a separator with an adhesive layer, and a secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 12)
In the preparation of the negative electrode slurry composition, the aqueous dispersion containing the acrylic polymer as the negative electrode binder was changed to 0.85 parts corresponding to the solid content, and the aqueous dispersion B was changed to 0.65 parts equivalent to the solid content. Except for the above, in the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, and the adhesive layer slurry composition An adhesive layer, a separator with an adhesive layer, and a secondary battery were manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 13)
In the preparation of the negative electrode slurry composition, the aqueous dispersion containing the acrylic polymer as the negative electrode binder was changed to 0.95 parts corresponding to the solid content, and the aqueous dispersion B was changed to 0.55 parts equivalent to the solid content. Except for the above, in the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, and the adhesive layer slurry composition An adhesive layer, a separator with an adhesive layer, and a secondary battery were manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 14)
In the preparation of the particulate polymer for the adhesive layer, the same procedure as in Example 1 was conducted except that methyl methacrylate was changed to 75 parts and butyl acrylate was changed to 20 parts as the (meth) acrylic acid ester monomer. , Negative electrode binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and two A secondary battery was manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 15)
In the preparation of the particulate polymer for the adhesive layer, as in Example 1, except that methyl methacrylate was changed to 95 parts as the (meth) acrylic acid ester monomer and butyl acrylate was not used. Binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and secondary battery Manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 16)
In the preparation of the particulate polymer for the adhesive layer, the same procedure as in Example 1 was conducted except that methyl methacrylate was changed to 40 parts and butyl acrylate was changed to 55 parts as the (meth) acrylic acid ester monomer. , Negative electrode binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and two A secondary battery was manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 17)
In the preparation of the binder for the adhesive layer, as the (meth) acrylic acid ester monomer, except that butyl acrylate was changed to 78 parts and 15 parts of 2-ethylhexyl acrylate was added, the same as in Example 1, Negative electrode binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and secondary A battery was manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 18)
In the preparation of the binder for the adhesive layer, as (meth) acrylic acid ester monomer, except that butyl acrylate was changed to 71 parts and 2-ethylhexyl acrylate was added 22 parts, the same as in Example 1, Negative electrode binder, negative electrode slurry composition, negative electrode, positive electrode, particulate polymer for adhesive layer, adhesive layer binder, adhesive layer slurry composition, adhesive layer, separator with adhesive layer, and secondary A battery was manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 19)
In the preparation of the binder for the adhesive layer, butyl acrylate was changed to 94.8 parts as the (meth) acrylic acid ester monomer, and acrylonitrile as the other polymerizable monomer was changed to 0.2 parts. Except that, in the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer slurry composition, An adhesive layer, a separator with an adhesive layer, and a secondary battery were manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 20)
In the preparation of the binder for the adhesive layer, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 3.5 parts, and acrylonitrile as the other polymerizable monomer was changed to 0.5 parts. Except that, in the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer slurry composition, An adhesive layer, a separator with an adhesive layer, and a secondary battery were manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 21)
In the preparation of the binder for the adhesive layer, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 4.5 parts, and as other polymerizable monomer, 0.5 part of acrylonitrile and acrylamide were added. Except for changing to 1 part, in the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer Slurry composition, adhesive layer, separator with adhesive layer, and secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Example 22)
In the preparation of the binder for the adhesive layer, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 1.2 parts, and acrylonitrile as the other polymerizable monomer was changed to 2.8 parts. Except that, in the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer slurry composition, An adhesive layer, a separator with an adhesive layer, and a secondary battery were manufactured.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Comparative Example 1)
In preparing the negative electrode binder, butyl acrylate as the (meth) acrylic acid ester monomer was changed to 99 parts, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 1 part, and In the same manner as in Example 1 except that acrylonitrile, N-methylolacrylamide, and acrylamide were not used as other polymerizable monomers, a negative electrode binder, a negative electrode slurry composition, a negative electrode, a positive electrode, A particulate polymer for the adhesive layer, a binder for the adhesive layer, a slurry composition for the adhesive layer, an adhesive layer, a separator with an adhesive layer, and a secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Comparative Example 2)
In preparing the negative electrode binder, methacrylic acid as the ethylenically unsaturated carboxylic acid monomer was changed to 0.3 part, and acrylonitrile as the other polymerizable monomer was changed to 3.7 parts. In the same manner as in Example 1, the negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, the adhesive layer binder, the adhesive layer slurry composition, the adhesive Layer, separator with adhesive layer, and secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

(Comparative Example 3)
In the preparation of the particulate polymer for the adhesive layer, the methacrylic acid as the ethylenically unsaturated carboxylic acid monomer used for the production of the core part is changed to 2 parts, and the polymerizable monomer used for the production of the shell part is used. The negative electrode binder, the negative electrode slurry composition, the negative electrode, the positive electrode, the particulate polymer for the adhesive layer, and the adhesive layer binder, except that the styrene was changed to 97 parts. Then, a slurry composition for an adhesive layer, an adhesive layer, a separator with an adhesive layer, and a secondary battery were produced.
And by the method similar to Example 1, the measurement and evaluation of the THF insoluble fraction, the glass transition temperature, the adhesiveness between battery members, the low-temperature output characteristics, and the cycle characteristics were performed. The results are shown in Table 1.

From Table 1, in the comparative example 1 using the binder for negative electrodes containing 95 mass% of (meth) acrylic acid ester monomer units, (meth) acrylic acid ester monomer units are 70 mass% or more and 95%. Compared with Examples 1-22 using the binder for negative electrodes containing below mass%, it turns out that the adhesiveness between the electrode members in a negative electrode and the low-temperature output characteristic of a secondary battery are remarkably deteriorated. Moreover, it turns out that the cycle output characteristic of a secondary battery is getting worse.
In Comparative Example 2 using the negative electrode binder containing less than 1% by mass of the ethylenically unsaturated carboxylic acid monomer unit, the ethylenically unsaturated carboxylic acid monomer unit is contained in an amount of 1% by mass to 5% by mass. Compared with Examples 1-22 using the binder for negative electrodes contained below, it turns out that the adhesiveness between the electrode members in a negative electrode and the cycling characteristics of a secondary battery are remarkably deteriorated. Moreover, it turns out that the low-temperature output characteristic of a secondary battery is getting worse.
Furthermore, in Comparative Example 3 using an adhesive layer containing a particulate polymer having a glass transition temperature of 110 ° C. or higher, compared with Examples 1 to 22 using an adhesive layer containing a particulate polymer having a glass transition temperature of 110 ° C. or lower. And it turns out that the adhesiveness between the electrode members in a negative electrode and the cycling characteristics of a secondary battery have deteriorated remarkably.

  ADVANTAGE OF THE INVENTION According to this invention, the non-aqueous secondary battery which has high adhesiveness between battery members, such as an electrode and a separator, and is excellent in battery performance, such as a cycle characteristic and an output characteristic, can be provided.

Claims (6)

A positive electrode, a negative electrode, a separator, an electrolytic solution, and an adhesive layer are provided.
The negative electrode contains a negative electrode active material, a (meth) acrylic acid ester monomer unit of 70% by mass to 95% by mass and an ethylenically unsaturated carboxylic acid monomer unit of 1% by mass to 5% by mass. Negative electrode binder A,
The adhesive layer is disposed between the negative electrode and the separator, and includes a particulate polymer having a glass transition temperature of 110 ° C. or lower.
Non-aqueous secondary battery.   The non-aqueous secondary battery according to claim 1, wherein the particulate polymer has a glass transition temperature of 10 ° C. or higher.   The adhesive layer contains a (meth) acrylate monomer unit of 70% by mass to 95% by mass and an ethylenically unsaturated carboxylic acid monomer unit of 1% by mass to 5% by mass. The nonaqueous secondary battery according to claim 1, further comprising a dressing.   The nonaqueous secondary battery according to any one of claims 1 to 3, wherein the negative electrode binder A has a tetrahydrofuran insoluble fraction of 70 mass% or more and 95 mass% or less.   The content rate of the said binder for negative electrodes A is 0.01 mass part or more and 1.0 mass part or less with respect to 100 mass parts of said negative electrode active materials, It is any one of Claims 1-4. Non-aqueous secondary battery.   The non-aqueous secondary battery according to any one of claims 1 to 5, which is a wound type or a laminated type.