JPWO2018131572A1 - Non-aqueous electrolyte battery electrode thickening stabilizer, binder composition containing the same, slurry composition for non-aqueous electrolyte battery electrode, non-aqueous electrolyte battery electrode and non-aqueous electrolyte battery - Google Patents

Abstract

The present invention relates to a thickening stabilizer for a nonaqueous electrolyte battery electrode, comprising a neutralized salt of an α-olefin-maleic acid copolymer obtained by copolymerization of an α-olefin and maleic acid, and a polyamine.

Description

  The present invention relates to a thickening stabilizer for a nonaqueous electrolyte battery electrode, a binder composition containing the same, a slurry composition for a nonaqueous electrolyte battery electrode, a nonaqueous electrolyte battery electrode, and a nonaqueous electrolyte battery.

  In recent years, mobile terminals such as mobile phones, notebook computers, and pad-type information terminal devices have been widely used. Lithium ion secondary batteries are frequently used as secondary batteries used for the power sources of these portable terminals. Since portable terminals are required to have more comfortable portability, miniaturization, thinning, weight reduction, and high performance have rapidly progressed, and have come to be used in various places. This trend continues today, and batteries used in mobile terminals are further required to be smaller, thinner, lighter, and higher in performance.

A non-aqueous electrolyte battery such as a lithium ion secondary battery has a positive electrode and a negative electrode installed via a separator, and LiPF ₆ , LiBF ₄ LiTFSI (lithium (bistrifluoromethylsulfonylimide)), LiFSI (lithium (bisfluorosulfonylimide). )) And a lithium salt dissolved in an organic liquid such as ethylene carbonate in a container.

The negative electrode and the positive electrode are usually a binder composition in which a binder and a thickening stabilizer are dissolved or dispersed in water, and an active material and, if necessary, a conductive additive (conductivity imparting agent) are mixed therewith. The electrode slurry (hereinafter, sometimes simply referred to as slurry) obtained in this manner is applied to a current collector and water is dried to form a mixed layer. More specifically, for example, in the case of a negative electrode, a carbonaceous material that can store and release lithium ions, which is an active material, and, if necessary, acetylene black as a conductive auxiliary agent, are used as a current collector such as copper. They are formed by binding with a secondary battery electrode binder. On the other hand, the positive electrode is formed by binding LiCoO ₂ as an active material and, if necessary, a conductive aid similar to the negative electrode to a current collector such as aluminum using a binder for a secondary battery electrode. Form.

  In the prior art, cellulose derivatives such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropoxycellulose, carboxymethylcellulose sodium salt (CMC-Na) have been proposed and used as thickening stabilizers for aqueous media (for example, Patent Document 1). Among these, CMC-Na is often used (for example, Patent Document 2).

  However, these cellulose derivatives are insulators that block the electrical conductivity between the active materials and do not have Li ion transportability, so the internal resistance increases and the battery capacity is inevitably reduced (Patent Document 3). . Recently, demands for extending the usage time of mobile devices and shortening charging time have increased, and there is an urgent need to improve battery capacity (low resistance), life (cycle characteristics), and charging speed (rate characteristics). In particular, it is an obstacle.

  Since it is the binder and the thickening stabilizer adsorbed on the active material surface that contribute to the increase in resistance, it is effective to suppress the amount of the cellulose derivative used as the thickening stabilizer to reduce the resistance. However, when the amount of the thickening stabilizer is reduced, the dispersibility of the active material in the slurry is lowered and aggregates are generated. Such aggregates not only promote a decrease in battery capacity, but also form bumps or defects on the coated electrode, which not only results in a decrease in electrode yield, but Li dendrites that cause battery short circuits are deposited, There is also a risk that safety may be significantly impaired. In addition, since the binding between the collecting electrode, the electrode material, and the active material in the electrode is reduced, the electrode is brittle and the electrode yield is reduced, and the durability (battery life) for a long time use is remarkably increased. There is also a risk of decline. For these reasons, it has been difficult to reduce the resistance while maintaining the binding property between the collector electrode and the electrode material.

  The present invention has been made in view of the above-mentioned problems, and functions as a thickening stabilizer, i.e., improved binding properties with a collector electrode and a battery in a nonaqueous electrolyte battery without impairing active material dispersibility. The purpose is to reduce the internal resistance.

JP 2008-288214 A JP 2011-192610 A JP 2013-257978 A

  As a result of diligent research to solve the above problems, the present inventors have found that the above object can be achieved by using a thickening stabilizer for a nonaqueous electrolyte battery having the following constitution, and further studies are made based on this finding. Thus, the present invention was completed.

  The thickening stabilizer according to one aspect of the present invention includes a neutralized salt of an α-olefin-maleic acid copolymer obtained by copolymerization of an α-olefin and maleic acid, and a polyamine.

  Hereinafter, although embodiment of this invention is described in detail, this invention is not limited to these.

  In the present embodiment, the “thickening stabilizer” for non-aqueous electrolyte batteries is not particularly limited, and is a slurry viscosity that is dissolved or dispersed in water to express its function and is suitable for coating. It has a function as a viscosity adjusting agent for adjusting to a region and a function as a dispersing agent for uniformly dispersing an active material in a solvent.

  The thickening stabilizer for a non-aqueous electrolyte battery according to this embodiment is characterized by containing a neutralized salt of an α-olefin-maleic acid copolymer obtained by copolymerizing an α-olefin and maleic acid, and a polyamine. To do.

  By using the thickening stabilizer for a non-aqueous electrolyte battery electrode having such a configuration, the binder for a non-aqueous electrolyte battery having binding properties and low resistance without impairing the dispersibility of the active material in the electrode slurry. A composition can be obtained. Furthermore, the internal resistance reduction of a nonaqueous electrolyte battery is realizable using it.

  In the present embodiment, an α-olefin-maleic acid copolymer obtained by copolymerizing an α-olefin and maleic acid is composed of a unit based on the α-olefin (A) and a unit based on the maleic acid (B). The components (A) and (B) preferably satisfy (A) / (B) = 1/1 to 1/3 (molar ratio). Moreover, it is preferable that it is a linear random copolymer whose average molecular weight is 10,000-500,000.

In this embodiment, the unit (A) based on α-olefins is represented by the general formula —CH ₂ CR ¹ R ² — (wherein R ¹ and R ² may be the same or different from each other, hydrogen Represents an alkyl group having 1 to 10 carbon atoms, an alkenyl or aryl group, an ether group, and a silyl group). The α-olefin used in the present embodiment is a linear or branched olefin having a carbon-carbon unsaturated double bond at the α-position. In particular, olefins having 2 to 12 carbon atoms, particularly 2 to 8 carbon atoms are preferred. Representative examples that may be used include ethylene, propylene, n-butylene, isobutylene, n-pentene, isoprene, 2-methyl-1-butene, 3-methyl-1-butene, n-hexene, 2-methyl- 1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2-ethyl-1-butene, 1,3-pentadiene, 1,3-hexadiene, 2,3-dimethylbutadiene, 2,5 -Pentadiene, 1,4-hexadiene, 2,2,4-trimethyl-1-pentene, styrene, α-methylstyrene, paramethylstyrene, methyl vinyl ether, ethyl vinyl ether and the like. Of these, isobutylene, ethylene, and methyl vinyl ether are particularly preferred from the viewpoints of availability, polysynthesis, and product stability. Here, the isobutylene includes a mixture containing isobutylene as a main component, for example, a BB fraction (C4 fraction). These olefins may be used alone or in combination of two or more.

  In the present embodiment, maleic anhydride, maleic acid, maleic acid monoester (for example, methyl maleate, ethyl maleate, propyl maleate, phenyl maleate, etc.), maleic acid, as the unit (B) based on maleic acids Maleic anhydride derivatives such as diesters (eg, dimethyl maleate, diethyl maleate, dipropyl maleate, diphenyl maleate, etc.), maleic imides or N-substituted derivatives thereof (eg maleic imide, N-methylmaleimide, N N-substituted alkylmaleimides such as ethylmaleimide, N-propylmaleimide, Nn-butylmaleimide, Nt-butylmaleimide, N-cyclohexylmaleimide, N-methylphenylmaleimide, N-ethylphenylmaleimide N-substituted alkylphenylmaleimides such as N- or N-substituted alkoxyphenylmaleimides such as N-methoxyphenylmaleimide and N-ethoxyphenylmaleimide), further halides thereof (for example, N-chlorophenylmaleimide), anhydrous citracone Acids, citraconic acid, citraconic acid monoesters (eg methyl citraconic acid, ethyl citraconic acid, propyl citraconic acid, phenyl citraconic acid, etc.), citraconic acid diesters (eg dimethyl citraconic acid, diethyl citraconic acid, dipropyl citraconic acid, citraconic acid Citraconic anhydride derivatives such as diphenyl, etc., citraconic imide or N-substituted derivatives thereof (for example, citraconic imide, 2-methyl-N-methylmaleimide, 2-methyl-N-ethylmale) N-substituted alkylmaleimides such as 2-methyl-N-propylmaleimide, 2-methyl-Nn-butylmaleimide, 2-methyl-Nt-butylmaleimide, 2-methyl-N-cyclohexylmaleimide 2-methyl-N-substituted alkylphenylmaleimide such as methyl-N-phenylmaleimide, 2-methyl-N-methylphenylmaleimide, 2-methyl-N-ethylphenylmaleimide, or 2-methyl-N-methoxyphenylmaleimide, Preferable examples include 2-methyl-N-substituted alkoxyphenylmaleimide such as 2-methyl-N-ethoxyphenylmaleimide) and further halides thereof (for example, 2-methyl-N-chlorophenylmaleimide). Among these, use of maleic anhydride is preferable from the viewpoint of availability, polymerization rate, and ease of molecular weight adjustment. These maleic acids may be used alone or in combination. Maleic acids are neutralized with alkali salts as described above, and the resulting carboxylic acid and carboxylic acid salt form a 1,2-dicarboxylic acid or salt form. This form has a function of capturing heavy metals eluted from the positive electrode.

As for the content rate of each said structural unit in the copolymer of this embodiment, it is desirable for (A) / (B) to exist in the range of 1 / 1-1 / 3 by molar ratio. This is because the advantages of hydrophilicity, water solubility, and affinity for metals and ions as a high molecular weight substance that dissolves in water can be obtained. In particular, the molar ratio of (A) / (B) is desirably 1/1 or a value close thereto, in which case the unit based on α-olefin, that is, —CH ₂ CR ¹ R ² — A copolymer having a structure in which the units shown and units based on maleic acids are alternately repeated is obtained.

  The mixing ratio of α-olefins and maleic acids for obtaining the copolymer of the present embodiment varies depending on the composition of the target copolymer, but α- 1 to 3 times the number of moles of maleic acids. Use of olefin is effective for increasing the reaction rate of maleic acids.

  The method for producing the copolymer of the present embodiment is not particularly limited, and for example, the copolymer can be obtained by radical polymerization. In this case, the polymerization catalyst used is an azo catalyst such as azobisisobutyronitrile, 1,1-azobiscyclohexane-1-carbonitrile, or an organic peroxide catalyst such as benzoyl peroxide or dicumyl peroxide. preferable. The amount of the polymerization catalyst used is required to be in the range of 0.1 to 5 mol% with respect to maleic acids, but is preferably 0.5 to 3 mol%. As a method for adding the polymerization catalyst and the monomer, they may be added all at the beginning of the polymerization, but it is desirable to add them sequentially as the polymerization proceeds.

In the method for producing a copolymer of this embodiment, the molecular weight can be appropriately adjusted mainly depending on the monomer concentration, the amount of catalyst used, and the polymerization temperature. For example, as a substance for reducing the molecular weight, a metal salt of Group I, II or III of the periodic table, a hydroxide, a halide of a Group IV metal, a general formula N≡, HN =, H ₂ N— or H It is also possible to adjust the molecular weight of the copolymer by adding an amine represented by ₄ N-, a nitrogen compound such as ammonium acetate or urea, or a mercaptan during the polymerization or during the polymerization. The polymerization temperature is preferably 40 ° C to 150 ° C, more preferably 60 ° C to 120 ° C. If the polymerization temperature is too high, the resulting copolymer tends to be in a block form, and the polymerization pressure may be significantly increased. The polymerization time is usually preferably about 1 to 24 hours, more preferably 2 to 10 hours. The amount of the polymerization solvent used is preferably adjusted so that the concentration of the obtained copolymer is 5 to 40% by weight, more preferably 10 to 30% by weight.

  As described above, it is preferable that the copolymer of the present embodiment usually has an average molecular weight of 10,000 to 500,000. A more preferable average molecular weight is 15,000 to 450,000. When the average molecular weight of the copolymer of the present embodiment is less than 10,000, the crystallinity is high and the adhesive strength between particles may be reduced. On the other hand, when it exceeds 500,000, the solubility in water or a solvent becomes small, and it may precipitate easily.

  The average molecular weight of the copolymer of this embodiment can be measured by, for example, a light scattering method or a viscosity method. When the intrinsic viscosity ([η]) in dimethylformamide is measured using a viscosity method, the copolymer of this embodiment preferably has an intrinsic viscosity in the range of 0.05-2. The copolymer of the present embodiment is usually obtained in the form of a powder having a grain size of about 16 to 60 mesh.

  In this embodiment, the neutralized salt of a copolymer is a neutralized product in which active hydrogen of carbonyl acid generated from maleic acids reacts with a basic substance to form a salt. Is preferred. In the neutralized α-olefin-maleic acid copolymer used in the present embodiment, a basic substance containing a monovalent metal and / or ammonia is used as the basic substance from the viewpoint of binding properties. It is preferable.

  The degree of neutralization is not particularly limited, but when used as a binder, considering the reactivity with the electrolytic solution, it is usually 0.3 to 1 mol of carboxylic acid produced from maleic acids. It is preferably in the range of 1 mol, and more preferably, a neutralized one in the range of 0.4 to 1 mol is used. With such a neutralization degree, the pH of the binder composition of the present embodiment can be adjusted to a predetermined range, and further, there is an advantage that the acidity is low and the electrolytic solution decomposition is suppressed.

  In this embodiment, the degree of neutralization can be determined by a method such as titration with a base, an infrared spectrum, or an NMR spectrum. To measure the neutralization point simply and accurately, titration with a base can be performed. preferable. The specific titration method is not particularly limited, but it can be dissolved in water with little impurities such as ion-exchanged water, and a basic substance such as lithium hydroxide, sodium hydroxide, potassium hydroxide, It can be carried out by neutralization. The indicator for the neutralization point is not particularly limited, but an indicator such as phenolphthalein whose pH is indicated by a base can be used.

  In the present embodiment, the amount of the basic substance containing monovalent metal and / or ammonia is not particularly limited and is appropriately selected depending on the purpose of use and the like, but usually in the maleic acid copolymer. The amount is preferably 0.1 to 2 mol per mol of maleic acid unit. If it is such usage-amount, it will be possible to adjust pH of the binder composition of this embodiment to the predetermined range. In addition, the usage-amount of the basic substance containing a monovalent metal becomes like this. Preferably, it is 0.6-2.0 mol per mol of maleic acid units in a maleic acid copolymer, More preferably, it is 0.7-2. When the amount is 0 mol, a water-soluble copolymer salt with little alkali residue can be obtained.

  The reaction of the α-olefin-maleic acid copolymer with a basic substance containing a monovalent metal and / or an amine such as ammonia can be carried out according to a conventional method, but is carried out in the presence of water, and α- A method of obtaining a neutralized olefin-maleic acid copolymer as an aqueous solution is simple and preferable.

  Examples of basic substances containing monovalent metals that can be used in the present embodiment include hydroxides of alkali metals such as sodium hydroxide, potassium hydroxide, and lithium hydroxide; alkali metals such as sodium carbonate and potassium carbonate. Carbonates of alkali metals such as sodium acetate and potassium acetate; phosphates of alkali metals such as trisodium phosphate, and the like. Examples of amines such as ammonia include primary amines such as ammonia, methylamine, ethylamine, butylamine and octylamine, secondary amines such as dimethylamine, diethylamine and dibutylamine, tertiary amines such as trimethylamine, triethylamine and tributylamine, And polyamines such as ethylenediamine, butylenediamine, diethyleneimine, triethyleneimine, and polyethyleneimine. Among these, ammonia, lithium hydroxide, sodium hydroxide, and potassium hydroxide are preferable. In particular, it is preferable to use ammonia or lithium hydroxide as a binder for a lithium ion secondary battery. The basic substance containing monovalent metal and / or ammonia may be used alone or in combination of two or more. Moreover, if it is in the range which does not have a bad influence on battery performance, the basic substance containing alkali metal hydroxides, such as sodium hydroxide, is used together, and the neutralized product of alpha-olefin-maleic acid copolymer May be prepared.

  Next, in this embodiment, the ring-opening rate of the copolymer represents the hydrolysis rate of the maleic anhydride sites that polymerize with α-olefins when maleic anhydride is used as the maleic acid. In the copolymer of the present embodiment, a preferable ring opening rate is 60 to 100%, more preferably 70% to 100%, and still more preferably 80 to 100%. If the ring-opening rate is too low, the structural freedom of the copolymer becomes small and the stretchability becomes poor, so that the force for adhering the electrode material particles to be bonded may be small, which is not preferable. Furthermore, there is a possibility that problems such as low affinity for water and poor solubility may occur. The ring-opening rate can be determined, for example, by measuring the hydrogen at the α-position of maleic acid opened by 1H-NMR with reference to the hydrogen at the α-position of maleic anhydride. The ratio of the carbonyl group derived from the carbonyl group and the ring-opened maleic anhydride can also be determined by IR measurement.

  In this embodiment, when the maleic acid is maleic anhydride, the neutralized salt of the copolymer means that the active hydrogen of the carbonyl acid generated by the ring opening of maleic anhydride is a basic substance as described above. It forms a salt by forming a salt. The degree of neutralization in this case is not particularly limited. However, when used as a thickening stabilizer, considering the reactivity with the electrolytic solution, usually 1 mol of carbonyl acid produced by ring opening. On the other hand, it is preferably in the range of 0.5 to 1 mol, more preferably in the range of 0.6 to 1 mol. Such a neutralization degree has the advantage of low acidity and suppression of electrolyte decomposition. The degree of neutralization of the copolymer when maleic anhydride is used can be measured by the same method as described above.

  In addition to the copolymer neutralization salt described above, the thickening stabilizer of this embodiment contains polyamines and forms a crosslinked structure. By crosslinking, it is possible to impart binding properties.

  The polyamines used in the present embodiment are not limited as long as they are electrochemically stable, but include low molecular weight substances having a molecular weight of less than 300 and / or high molecular weight substances having a molecular weight of 300 or more.

  Specific examples of the low molecular weight polyamines include aliphatic polyamines, aromatic polyamines, and heterocyclic polyamines. Preferable specific examples include, for example, aliphatic polyamines such as ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, and guanidine; aromatic polyamines such as phenylenediamine; and heterocyclic polyamines such as piperazine and N-aminoethylpiperazine. Etc.

  Specific examples of the high molecular weight polyamines include amino group-containing polymers, and preferred specific examples thereof include polyethyleneimine, polytetramethyleneimine, polyvinylamine, polyallylamine, dicyandiamide-formalin condensate, dicyandiamide-alkylene ( Polyamine) condensates and the like. These may be used alone or in combination. In view of availability and economy, it is preferable to use polyethyleneimine.

  The molecular weight of these polyamines is not particularly limited, and the average molecular weight is in the range of 50 to 200,000, more preferably in the range of 100 to 180,000, and most preferably in the range of 200 to 100,000. .

  Moreover, the addition amount of the polyamines in the thickening stabilizer of the present embodiment is not particularly limited, but is usually 100 parts by weight of an α-olefin-maleic acid copolymer (solid content). 0.01 parts by weight to 10 parts by weight, more preferably 0.02 parts by weight to 6 parts by weight. Too much addition amount is not preferable because it forms a complex salt with an α-olefin-maleic acid copolymer, and gelation of the strength due to multi-crosslinking proceeds, and water is constrained and difficult to dry. On the other hand, an excessively small addition amount is not preferable because sufficient binding properties cannot be imparted.

  In the present embodiment, the polyamines can be added simultaneously with the reaction of the α-olefin-maleic acid copolymer and a basic substance containing a monovalent metal, or the α-olefin-maleic acid copolymer and It can also be added after reacting a basic substance containing a monovalent metal. Usually, the temperature for accelerating the crosslinking reaction is not particularly limited, but the crosslinking reaction proceeds rapidly by heating at 20 ° C. or higher, preferably 30 ° C. or higher. The time required for convergence of the crosslinking reaction is not limited because it depends on the temperature, but the crosslinking reaction usually converges in about 0.1 hour to 2 months.

  The viscosity of the thickening stabilizer of this embodiment is in the range of 100-30000 cP, more preferably in the range of 1000-10000 cP. When the viscosity is 100 cP or less, the coatability is greatly deteriorated due to a significant decrease in slurry viscosity. When the viscosity is 30000 cP or more, the wettability with respect to the active material or the conductive auxiliary agent is poor at the time of slurry preparation, and the dispersibility of the active material or conductive auxiliary agent in the slurry is greatly reduced.

Next, the binder composition for nonaqueous electrolyte battery electrodes of this embodiment will be described. The binder composition usually contains the thickening stabilizer and particulate binder of the present embodiment described above.

The particulate binder that can be used in the present embodiment is not particularly limited as long as it is particulate and has a binding property to an active material and / or a current collector described later. Examples of suitable particulate binders include dispersion type binders that are excellent in dispersibility in a dispersion medium. Specific dispersion type binders include, for example, fluorine polymers, diene polymers, vinyl aromatic / conjugated diene random or block copolymers, acrylic polymers, polyimides, polyamides, polyurethane polymers, and the like. A high molecular compound is mentioned.

The diene polymer is a homopolymer of a conjugated diene, a vinyl aromatic, a random or block copolymer obtained by polymerizing a monomer mixture containing a conjugated diene, or a hydrogenated product thereof. Specific examples of the diene polymer include conjugated diene homopolymers such as polybutadiene and polyisoprene; aromatic vinyl / conjugated diene copolymers such as carboxy-modified styrene / butadiene copolymer (SBR); Examples thereof include vinyl cyanide / conjugated diene copolymers such as acrylonitrile / butadiene copolymer (NBR); hydrogenated SBR, hydrogenated NBR, and the like.

The acrylic polymer is a homopolymer of acrylic ester or methacrylic ester or a copolymer with a monomer copolymerizable therewith. Examples of the copolymerizable monomer include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and fumaric acid; two or more carbons such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, and trimethylolpropane triacrylate. -Carboxylic acid ester having a carbon double bond; styrene, chlorostyrene, vinyl toluene, t-butyl styrene, vinyl benzoic acid, vinyl benzoate methyl, vinyl naphthalene, chloromethyl styrene, hydroxymethyl styrene, α-methyl styrene, Styrene monomers such as divinylbenzene; Amide monomers such as acrylamide, N-methylolacrylamide, and acrylamide-2-methylpropane sulfonic acid; α, β-defect such as acrylonitrile and methacrylonitrile Japanese nitrile compounds; olefins such as ethylene and propylene; diene monomers such as butadiene and isoprene; monomers containing halogen atoms such as vinyl chloride and vinylidene chloride; vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate Vinyl esters such as methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, etc .; Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, butyl vinyl ketone, hexyl vinyl ketone, isopropenyl vinyl ketone; N-vinyl pyrrolidone, vinyl Heterocycle-containing vinyl compounds such as pyridine and vinylimidazole; and hydroxyalkyl group-containing compounds such as β-hydroxyethyl acrylate and β-hydroxyethyl methacrylate.

Among these, acrylic polymers, SBR, NBR, and hydrogenated SBR are preferably used, and acrylic polymers, SBR, and hydrogenated SBR are more preferably used.

In the binder of the present embodiment, “particulate” means polymer fine particles obtained mainly by emulsion polymerization of monomers constituting the above-mentioned polymer, or a polymer emulsified and emulsified after polymerization. Refers to fine particles. There is no limitation in particular as an emulsion polymerization method, What is necessary is just to employ | adopt a conventionally well-known emulsion polymerization method. The particle size of the particulate binder is preferably 0.01 to 0.5 μm, and more preferably 0.01 to 0.3 μm. When the particle diameter is 0.01 μm or less, the increase in slurry viscosity is remarkably caused to deteriorate the coatability. Further, when the particle diameter is 0.5 μm or more, the binder dispersibility in the electrode is lowered, and the adhesiveness is lowered.

Further, in the binder of this embodiment, a protective colloid may be added in order to stabilize the above-mentioned polymer fine particles. The protective colloid used in the present invention refers to a hydrocolloid added for the purpose of stabilizing the hydrophobic colloid with respect to the electrolyte. This stabilizing action is thought to be because the hydrocolloid particles enclose the hydrophobic colloid particles and the properties of the hydrocolloid appear as a whole. Examples of protective colloids include polyvinyl alcohol, modified polyvinyl alcohol; water-soluble cellulose derivatives such as methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, and hydroxypropyl cellulose; water-soluble salts of (meth) acrylate-unsaturated carboxylic acid copolymers; styrene -Maleic anhydride copolymer salt, maleated polybutadiene salt, naphthalene sulfonate, polyacrylate and the like. These protective colloids can be used alone or in combination of two or more. Among these, in the present invention, it is preferable to use a water-soluble salt of a (meth) acrylate-unsaturated carboxylic acid copolymer and / or polyvinyl alcohol as the protective colloid, and (meth) acrylate- It is very preferable to use a water-soluble salt of an unsaturated carboxylic acid copolymer.

In addition, the nonaqueous electrolyte battery binder composition of the present embodiment is usually a slurry composition for a nonaqueous electrolyte battery electrode (hereinafter simply referred to as “a nonaqueous electrolyte battery electrode slurry”), which further contains an active material and water in addition to the binder composition described above. It is preferably used as a slurry composition). That is, the slurry composition of the present embodiment contains the thickening stabilizer and the particulate binder of the present embodiment described above, an active material, water, and a protective colloid that stabilizes the polymer fine particles as necessary. To do.

Further, in the present embodiment, the nonaqueous electrolyte battery electrode is characterized in that a mixed layer containing at least the binder composition and the active material of the present embodiment is bound to a current collector. This electrode can be formed by applying the slurry composition described above to a current collector and then removing the solvent by a method such as drying. If necessary, a conductive additive or the like can be added to the mixed layer.

In the slurry composition for a non-aqueous electrolyte battery, the amount of the thickening stabilizer used relative to 100 parts by weight of the active material is usually preferably 0.1 to 4 parts by weight, more preferably 0.3 to 3 parts. Parts by weight, more preferably 0.5 to 2 parts by weight. If the amount of the thickening stabilizer is too small, the viscosity of the slurry may be too low and the thickness of the mixed layer may be reduced. Conversely, if the amount of the thickening stabilizer is too large, the discharge capacity may be reduced. .

The amount of the particulate binder in the slurry composition is usually preferably 0.1 to 4 parts by weight, more preferably 0.1 to 2 parts by weight with respect to 100 parts by weight of the active material. is there. If the amount of the particulate binder is excessively large, the internal resistance of the battery may be increased. Conversely, if the amount is too small, the binding property is remarkably lowered.

As the solvent in the negative electrode slurry composition of the present embodiment, in addition to the above water, for example, alcohols such as methanol, ethanol, propanol and 2-propanol, cyclic ethers such as tetrahydrofuran and 1,4-dioxane, N, Amides such as N-dimethylformamide and N, N-dimethylacetamide, cyclic amides such as N-methylpyrrolidone and N-ethylpyrrolidone, and sulfoxides such as dimethylsulfoxide can also be used. In these, use of water is preferable from a viewpoint of safety.

In addition to water as a solvent for the negative electrode slurry composition of the present embodiment, the following organic solvent may be used in combination within a range of preferably 20% by weight or less of the total solvent. As such an organic solvent, those having a boiling point of 100 ° C. or more and 300 ° C. or less at normal pressure are preferable, for example, hydrocarbons such as n-dodecane; alcohols such as 2-ethyl-1-hexanol and 1-nonanol. Esters such as γ-butyrolactone and methyl lactate; amides such as N-methylpyrrolidone, N, N-dimethylacetamide and dimethylformamide; organic dispersion media such as sulfoxides and sulfones such as dimethyl sulfoxide and sulfolane.

When the slurry composition of the present embodiment is used for a negative electrode, examples of the negative electrode active material (sometimes abbreviated as active material) added to the negative electrode slurry composition include amorphous carbon, graphite, natural graphite, Carbonaceous materials such as mesocarbon microbeads (MCMB) and pitch-based carbon fibers; conductive polymers such as polyacene; composite metal oxides represented by SiOx, SnOx, LiTiOx, other metal oxides, lithium metal, lithium Examples thereof include lithium-based metals such as alloys; metal compounds such as TiS ₂ and LiTiS ₂ .

In this embodiment, a thickener can be further added to the slurry composition as necessary. The thickener that can be added is not particularly limited, and various alcohols, in particular, polyvinyl alcohol and modified products thereof, celluloses, starches, and other polysaccharides can be used.

The amount of the thickener used in the slurry composition as needed is preferably about 0.1 to 4 parts by weight, more preferably 0.3 to 3 parts by weight with respect to 100 parts of the negative electrode active material. More preferably, it is 0.5 to 2 parts by weight. If the thickener is too small, the viscosity of the secondary battery negative electrode slurry may be too low and the thickness of the mixed layer may be reduced. Conversely, if the thickener is excessively large, the discharge capacity may be reduced. .

Moreover, as a conductive support agent mix | blended with a slurry composition as needed, metal powder, a conductive polymer, acetylene black etc. are mentioned, for example. The amount of the conductive aid used is usually preferably 0.5 to 10 parts by weight, more preferably 1 to 7 parts by weight with respect to 100 parts by weight of the negative electrode active material.

The current collector used for the nonaqueous electrolyte battery electrode of the present embodiment is not particularly limited as long as it is made of a conductive material. In the case of a negative electrode, for example, iron, copper, aluminum, nickel, stainless steel, titanium Metal materials such as tantalum, gold, and platinum can be used. One of these may be used alone, or two or more of these may be used in combination at any ratio.

In particular, when copper is used as the negative electrode, the effect of the slurry for nonaqueous electrolyte battery electrodes of the present invention is most apparent. The shape of the current collector is not particularly limited, but usually a sheet shape having a thickness of about 0.001 to 0.5 mm is preferable.

The method for applying the slurry to the current collector is not particularly limited. Examples thereof include a doctor blade method, a dip method, a reverse roll method, a direct roll method, a gravure method, an extrusion method, a dipping method, and a brush coating method. The amount to be applied is not particularly limited, but the thickness of the mixed layer containing the active material, conductive additive, binder and thickener formed after removing the solvent or dispersion medium by a method such as drying is preferably 0.005 to 0.005. An amount of 5 mm, more preferably 0.01 to 2 mm is common.

The method for drying a solvent such as water contained in the slurry composition is not particularly limited, and examples thereof include aeration drying with hot air, hot air, and low-humidity air; vacuum drying; drying with infrared rays, far infrared rays, electron beams, and the like. . The drying conditions are preferably adjusted so that the solvent can be removed as soon as possible while the active material layer is cracked by stress concentration or the active material layer does not peel from the current collector. Furthermore, in order to increase the density of the active material of the electrode, it is effective to press the current collector after drying. Examples of the pressing method include a die press and a roll press.

Furthermore, the present invention also includes a nonaqueous electrolyte battery having the negative electrode. When the electrode of the present embodiment is a negative electrode, the nonaqueous electrolyte battery usually includes the negative electrode, the positive electrode, and an electrolytic solution.

In this embodiment, the positive electrode normally used for nonaqueous electrolyte batteries, such as a lithium ion secondary battery, is especially used for a positive electrode without a restriction | limiting. For example, as the positive electrode active material, TiS ₂ , TiS ₃ , amorphous MoS ₃ , Cu ₂ V ₂ O ₃ , amorphous V ₂ O—P ₂ O ₅ , MoO ₃ , V ₂ O ₅ , V ₆ O Transition metal oxides such as ₁₃ and lithium-containing composite metal oxides such as LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , and LiMn ₂ O ₄ are used. Further, the positive electrode active material is made of a conductive additive similar to that of the negative electrode, and a binder such as SBR, NBR, acrylic rubber, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinylidene fluoride, and the boiling point at 100 ° C. in water or the above normal pressure. The positive electrode slurry prepared by mixing in a solvent of 300 ° C. or lower can be applied to a positive electrode current collector such as aluminum and the solvent can be dried to obtain a positive electrode.

In the nonaqueous electrolyte battery of this embodiment, an electrolytic solution in which an electrolyte is dissolved in a solvent can be used. The electrolyte solution may be liquid or gel as long as it is used for a non-aqueous electrolyte battery such as a normal lithium ion secondary battery, and functions as a battery depending on the type of the negative electrode active material and the positive electrode active material. What is necessary is just to select suitably. Specific electrolytes, for example, also known lithium salt is any conventionally _{available, LiClO 4, LiBF 6, LiPF} 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF 6, LiSbF 6, LiB 10 Cl 10 , LiAlCl ₄ , LiCl, LiBr, LiB (C ₂ H ₅ ) ₄ , CF ₃ SO ₃ Li, CH ₃ SO ₃ Li, LiCF ₃ SO ₃ , LiC ₄ F ₉ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N And lower aliphatic lithium carboxylates.

A solvent (electrolyte solvent) for dissolving such an electrolyte is not particularly limited. Specific examples include carbonates such as propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, and diethyl carbonate; lactones such as γ-butyllactone; trimethoxymethane, 1,2-dimethoxyethane, diethyl ether, and 2-ethoxyethane. Ethers such as dimethyl sulfoxide; oxolanes such as 1,3-dioxolane and 4-methyl-1,3-dioxolane; nitrogen-containing compounds such as acetonitrile and nitromethane; formic acid Organic acid esters such as methyl, methyl acetate, ethyl acetate, butyl acetate, methyl propionate and ethyl propionate; inorganic acid esters such as triethyl phosphate, dimethyl carbonate and diethyl carbonate Terigres; diglymes; triglymes; sulfolanes; oxazolidinones such as 3-methyl-2-oxazolidinone; sultones such as 1,3-propane sultone, 1,4-butane sultone, naphtha sultone, and the like. Alternatively, two or more kinds can be mixed and used. When a gel electrolyte is used, a nitrile polymer, an acrylic polymer, a fluorine polymer, an alkylene oxide polymer, or the like can be added as a gelling agent.

Although there is no limitation in particular as a method of manufacturing the nonaqueous electrolyte battery of this embodiment, For example, the following manufacturing method is illustrated. That is, the negative electrode and the positive electrode are overlapped with each other via a separator such as a polypropylene porous membrane, wound or folded according to the shape of the battery, put into a battery container, injected with an electrolyte, and sealed. The shape of the battery may be any known coin type, button type, sheet type, cylindrical type, square type, flat type, and the like.

The nonaqueous electrolyte battery of this embodiment is a battery that achieves both improved adhesion and improved battery characteristics, and is useful for various applications. For example, the battery is very useful as a battery used in a portable terminal that is required to be small, thin, light, and have high performance.

  As described above, the present specification discloses various modes of technology, of which the main technologies are summarized below.

  The thickening stabilizer according to one aspect of the present invention includes a neutralized salt of an α-olefin-maleic acid copolymer obtained by copolymerization of an α-olefin and maleic acid, and a polyamine.

  With such a configuration, it is possible to improve the binding property with the collector electrode and reduce the internal resistance in the non-aqueous electrolyte battery without impairing the active material dispersibility in the electrode slurry.

  Moreover, the binder aqueous solution for nonaqueous electrolyte battery electrodes which concerns on the other situation of this invention contains the said thickening stabilizer and a particulate-form binder.

  Moreover, the slurry composition for nonaqueous electrolyte battery electrodes which concerns on the other situation of this invention contains the said binder composition for nonaqueous electrolyte battery electrodes, an active material, and a solvent, It is characterized by the above-mentioned.

  A nonaqueous electrolyte battery electrode according to still another aspect of the present invention is formed by binding a current collector to a mixed layer containing at least the binder composition for a nonaqueous electrolyte battery electrode and an active material. Features.

  A nonaqueous electrolyte battery according to still another aspect of the present invention includes the nonaqueous electrolyte battery electrode.

  Examples of the present invention will be described below, but the present invention is not limited thereto.

Example 1
<Thickening stabilizer for negative electrode>
As a thickening stabilizer for negative electrode, lithium-modified isobutene-maleic anhydride copolymer resin (average molecular weight 325,000, neutralization degree 0.5, ring opening rate 96%) 10% by weight aqueous solution and polyethyleneimine (PEI, Wako Pure) Yaku Kogyo Co., Ltd., average molecular weight 10,000) 10% by weight aqueous solution was mixed to a weight ratio of 99: 1 (resin: PEI = 6.387: 0.065 as solid content). The obtained mixture was heated to 90 ° C. and stirred for 2 hours. Thereafter, water was added to the obtained mixed solution so as to have a solid content concentration of 5.5% by weight, and the mixture was homogeneously stirred for 2 hours at a rotation speed of 3,600 rpm using a mixer mill to obtain a thickening stabilizer.

<Preparation of slurry for negative electrode>
The slurry for the electrode was prepared by using 2.08 parts by weight of TRD2001 (manufactured by SBR, JSR) as a solid binder and 1008 parts by weight of DMGS (natural graphite, manufactured by BYD) as an active material for the negative electrode. 1.04 parts by weight of a thickening stabilizer as a solid content, and 1.04 parts by weight of Super-P (manufactured by Timcal) as a conductive aid (conductivity imparting agent) as a solid content are put into a dedicated container, It knead | mixed using the stirrer (ARE-250, the product made from Sinky). In order to adjust the viscosity of the slurry, an electrode coating slurry was prepared by adding water at the time of kneading and kneading again. The composition ratio of the active material and the binder in the slurry is, as a solid content, graphite powder: conductive aid: binder composition = 100: 1.04: 3.12.

<Preparation of negative electrode for battery>
The obtained slurry was coated on a current collector copper foil (CST8G, manufactured by Fukuda Metal Foil Co., Ltd.) using a bar coater (T101, manufactured by Matsuo Sangyo), and then heated at 80 ° C. for 30 minutes with a hot air dryer (Yamato). After primary drying in (Science), rolling was performed using a roll press (made by Hosen). Then, after punching out as a battery electrode (φ14 mm), a coin battery electrode was produced by secondary drying under reduced pressure conditions at 120 ° C. for 3 hours.

<Electrode toughness test>
Evaluation of electrode toughness is based on JIS K5600-5-1 (General coating test method-Part 5: Mechanical properties of coating film-Section 1: Bending resistance (cylindrical mandrel method)) of type 1 test equipment. Used. The electrode cracks were confirmed visually, and the results of the minimum mandrel diameter at which no cracks occurred are shown in Table 1 below. In addition, toughness is so high that a mandrel diameter is small, and it is preferable to use it as an electrode as it is 5 mm or less.

<Measurement of peel strength of electrode>
The strength when the electrode was peeled off from the copper foil as the collecting electrode was measured. The peel strength was measured at 180 ° peel strength using a 50N load cell (manufactured by Imada Co., Ltd.). The slurry-coated surface of the battery-coated electrode obtained above and a stainless steel plate were bonded together using a double-sided tape (double-faced tape made by Nichiban), and the 180 ° peel strength (peel width 10 mm, peel rate 100 mm / min) was measured. did. The results are shown in Table 1 below.

<Production of battery>
The battery coating electrode obtained above was transferred to a glove box (Miwa Seisakusho) under an argon gas atmosphere. A metal lithium foil (thickness 0.2 mm, φ16 mm) was used for the positive electrode. In addition, a polypropylene system (Celgard # 2400, manufactured by Polypore) is used as a separator, and the electrolyte is ethylene carbonate (EC) of lithium hexafluorophosphate (LiPF ₆ ) and vinylene carbonate (EMC) with vinylene carbonate (EMC). VC) was added using a mixed solvent system (1M-LiPF ₆ , EC / EMC = 3/7 vol%, VC 2 wt%) to prepare a coin battery (2032 type).

<Evaluation method: charge / discharge characteristic test>
The produced coin battery was subjected to a charge / discharge test using a commercially available charge / discharge tester (TOSCAT3100, manufactured by Toyo System). The coin battery is placed in a constant temperature bath at 25 ° C., and charging is performed at a constant current of 0.1 C (about 0.5 mA / cm ² ) with respect to the amount of active material until the voltage reaches 0 V with respect to the lithium potential. On the other hand, the constant voltage charge of 0V was implemented to the electric current of 0.02 mA. The capacity at this time was defined as a charging capacity (mAh / g). Next, a constant current discharge of 0.1 C (about 0.5 mA / cm ² ) was performed up to 1.5 V with respect to the lithium potential, and the capacity at this time was defined as a discharge capacity (mAh / g). The difference between the initial discharge capacity and the charge capacity was defined as irreversible capacity, and the percentage of discharge capacity / charge capacity was defined as charge / discharge efficiency. As the direct current resistance of the coin battery, a resistance value after being charged once (fully charged state) was adopted. The results are shown in Table 1 below.

(Example 2)
As a negative electrode active material, DMGS (natural graphite, manufactured by BYD) 100 parts by weight TRD2001 (SBR, manufactured by JSR) as a solid binder, 2.08 parts by weight as a solid content, the same thickening as in Example 1 A stabilizer is used as 1.56 parts by weight as a solid content, and Super-P (manufactured by Timcal) as a conductive auxiliary agent (conductivity imparting agent) is used as a solid content at 1.04 parts by weight in a dedicated container. ARE-250, manufactured by Shinky Corporation). In order to adjust the viscosity of the slurry, an electrode coating slurry was prepared by adding water at the time of kneading and kneading again. Then, the coated electrode was produced by the method similar to the said Example 1, and the toughness test and the peeling strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

(Example 3)
As a negative electrode active material DMGS (natural graphite, BYD) 100 parts by weight, TRD2001 (SBR, manufactured by JSR) as a solid binder, 2.08 parts by weight as a solid content, thickening stability of Example 1 2.08 parts by weight of the agent as a solid content and 1.04 parts by weight of Super-P (manufactured by Timcal) as a conductive auxiliary agent (conductivity imparting agent) as a solid content are put into a special container, and a planetary stirrer (ARE -250, manufactured by Shinky Corporation). In order to adjust the viscosity of the slurry, an electrode coating slurry was prepared by adding water at the time of kneading and kneading again. Then, the coated electrode was produced by the method similar to the said Example 1, and the toughness test and the peeling strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

Example 4
As a thickening stabilizer for the negative electrode, lithium-modified methyl vinyl ether-maleic anhydride copolymer resin (average molecular weight 630,000, neutralization degree 0.5, ring opening rate 98%) 10% by weight aqueous solution and polyethyleneimine (PEI, sum) A 10 wt% aqueous solution with an average molecular weight of 10,000, manufactured by Kojun Pharmaceutical Co., Ltd., was mixed at a weight ratio of 99: 1 (resin: PEI = 6.387: 0.065 as solid content). The obtained mixture was heated to 90 ° C. and stirred for 2 hours. Thereafter, water was added to the obtained mixed solution so as to have a solid content concentration of 5.5% by weight, and the mixture was homogeneously stirred for 2 hours at a rotation speed of 3,600 rpm using a mixer mill. Thereafter, a slurry and a coated electrode were prepared by the same method as in Example 1, and a toughness test and a peel strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

(Example 5)
As a thickening stabilizer for negative electrode, lithium-modified ethylene-maleic anhydride copolymer resin (average molecular weight 100,000, neutralization degree 0.5, ring-opening rate 99%) 10% by weight aqueous solution and polyethyleneimine (PEI, Wako Pure) Yaku Kogyo Co., Ltd., average molecular weight 10,000) 10% by weight aqueous solution was mixed to a weight ratio of 99: 1 (resin: PEI = 6.387: 0.065 as solid content). The obtained mixture was heated to 90 ° C. and stirred for 2 hours. Thereafter, water was added to the obtained mixed solution so as to have a solid content concentration of 5.5% by weight, and the mixture was homogeneously stirred for 2 hours at a rotation speed of 3,600 rpm using a mixer mill. Thereafter, a slurry / coated electrode was prepared by the same method as in Example 1, and a toughness test and a peel strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

(Example 6)
<Particulate binder>
Hydrogenated block copolymer dissolved in 15 g of polyvinyl alcohol (trade name, manufactured by Kuraray Co., Ltd., Poval 405 (polymerization degree 500, saponification degree 81.5%)) and 300 g of toluene in a 1 L homogenizer equipped with a homomixer. (Septon 2002 (trade name, manufactured by Kuraray Co., Ltd., hydrogenated product of styrene-isoprene-styrene triblock copolymer, styrene content 30%) 150 g and 500 g of water were sequentially added, and 10 revolutions at 15,000 rpm at room temperature. The mixture was stirred for 5 minutes and transferred to a pressure homogenizer for emulsification, and the resulting dispersion was distilled off toluene and water using a rotary evaporator under reduced pressure and warming (60 ° C.). An aqueous emulsion having an average particle size of 0.3 μm was obtained.

<Preparation of slurry for negative electrode>
The electrode slurry was prepared as follows: 1008 parts by weight of DMGS (natural graphite, manufactured by BYD) as the negative electrode active material, 2.08 parts by weight of the above-mentioned particulate binder as a solid content, the same thickening stability as in Example 1 1.04 parts by weight of the agent as a solid content and 1.04 parts by weight of Super-P (manufactured by Timcal Co.) as a conductive auxiliary agent (conductivity imparting agent) as a solid content in a dedicated container. ARE-250, manufactured by Shinky Corporation). In order to adjust the viscosity of the slurry, an electrode coating slurry was prepared by adding water at the time of kneading and kneading again. Then, the coated electrode was produced by the method similar to the said Example 1, and the toughness test and the peeling strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

(Comparative Example 1)
A lithium-modified isobutene-maleic anhydride copolymer resin (average molecular weight 325,000, neutralization degree 0.5, ring-opening rate 96%) 10% by weight aqueous solution was used as a thickening stabilizer for the negative electrode. A slurry / coated electrode was prepared by the same method, and a toughness test and a peel strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

(Comparative Example 2)
As a negative electrode active material, DMGS (natural graphite, manufactured by BYD) 100 parts by weight, as a particulate binder, TRD2001 (SBR, manufactured by JSR) is 2.08 parts by weight as a solid content, and carboxymethylcellulose as a thickening stabilizer. 1.08 parts by weight as a solid content and Super-P (manufactured by Timcal) as a conductive auxiliary agent (conductivity imparting agent) at 1.04 parts by weight as a solid content in a dedicated container, and a planetary stirrer (ARE- 250, manufactured by Shinky Corporation). In order to adjust the viscosity of the slurry, an electrode coating slurry was prepared by adding water at the time of kneading and kneading again. Then, the coated electrode was produced by the method similar to the said Example 1, and the toughness test and the peeling strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

(Comparative Example 3)
As a negative electrode active material, DMGS (natural graphite, manufactured by BYD) 100 parts by weight, as a particulate binder, TRD2001 (SBR, manufactured by JSR) is 2.08 parts by weight as a solid content, and hydroxyethyl cellulose as a thickening stabilizer. 1.08 parts by weight as a solid content and Super-P (manufactured by Timcal) as a conductive auxiliary agent (conductivity imparting agent) at 1.04 parts by weight as a solid content in a dedicated container, and a planetary stirrer (ARE- 250, manufactured by Shinky Corporation). In order to adjust the viscosity of the slurry, an electrode coating slurry was prepared by adding water at the time of kneading and kneading again. Then, the coated electrode was produced by the method similar to the said Example 1, and the toughness test and the peeling strength measurement were performed. Furthermore, the coin battery using this electrode was obtained and the charge / discharge characteristic test was done. These evaluation results are shown in Table 1.

(Discussion)
Examples 1-6 and the comparative example 1 were low resistance compared with the comparative examples 2-3 using the cellulose derivative. This is because Examples 1 to 6 and Comparative Example 1 have dicarboxylic acid units in the structure, so that Li ion hopping through carboxylic acid groups occurs and expresses Li ion conductivity. Yes. Moreover, about binding property, Examples 1-6 were highly adhesive compared with Comparative Examples 1-3. This is considered to be due to the cross-linking by polyamine and the excellent binding property of the polymer alone compared to the cellulose derivative. From the above, it was shown that excellent binding property and resistance reduction can be realized by using the thickening stabilizer of the present invention.

  This application is based on Japanese Patent Application No. 2017-005051 filed on January 16, 2017 and Japanese Patent Application No. 2017-094146 filed on May 10, 2017. Are included in this application.

  In order to express the present invention, the present invention has been described appropriately and sufficiently through the embodiments with reference to specific examples and the like. However, those skilled in the art can easily change and / or improve the above-described embodiments. It should be recognized that this is possible. Accordingly, unless the modifications or improvements implemented by those skilled in the art are at a level that departs from the scope of the claims recited in the claims, the modifications or improvements are not limited to the scope of the claims. To be construed as inclusive.

  The present invention has wide industrial applicability in the technical field related to non-aqueous electrolyte batteries such as lithium ion secondary batteries.

Claims (5)

  A thickening stabilizer for a non-aqueous electrolyte battery electrode, comprising a neutralized salt of an α-olefin-maleic acid copolymer obtained by copolymerization of an α-olefin and maleic acid and a polyamine.   A binder composition for a non-aqueous electrolyte battery electrode, comprising the thickening stabilizer according to claim 1 and a particulate binder.   A slurry composition for a nonaqueous electrolyte battery electrode, comprising the binder composition according to claim 2, an active material, and water.   A nonaqueous electrolyte battery electrode obtained by binding a mixed layer containing the binder composition according to claim 2 and an active material to a current collector.   A nonaqueous electrolyte battery comprising the nonaqueous electrolyte battery electrode according to claim 4.