JP6222183B2 - Battery packaging materials - Google Patents

Description

  The present invention relates to a battery packaging material having high moldability and excellent battery continuous productivity.

  Conventionally, various types of batteries have been developed. In any battery, a packaging material is an indispensable member for sealing battery elements such as electrodes and electrolytes. Conventionally, metal packaging materials have been widely used as battery packaging, but in recent years, with the increasing performance of electric vehicles, hybrid electric vehicles, personal computers, cameras, mobile phones, etc., batteries are required to have various shapes. At the same time, there is a demand for reduction in thickness and weight. However, metal battery packaging materials that have been widely used in the past have the disadvantages that it is difficult to follow the diversification of shapes and that there is a limit to weight reduction.

  Therefore, a film-like laminate in which a base material layer / adhesive layer / metal layer / sealant layer are sequentially laminated is proposed as a battery packaging material that can be easily processed into various shapes and can be made thinner and lighter. (For example, refer to Patent Document 1). Such a film-shaped battery packaging material is formed so that the battery element can be sealed by causing the sealant layers to face each other and heat-sealing the peripheral portion by heat sealing.

  In the battery packaging material, when the battery element is encapsulated, it is molded with a mold to form a space for accommodating the battery element. There is a problem that cracks and pinholes are likely to occur in the metal layer at the flange portion of the mold due to the battery packaging material being stretched during this molding. In particular, with the recent demand for smaller and thinner batteries, thinner battery packaging materials are required, and such problems are more likely to occur. In order to solve such a problem, a method of increasing the slipperiness of the base material layer by forming a lubricant coating layer on the surface of the base material layer located in the outermost layer of the battery packaging material is known. . Similarly, it is also conceivable to form a lubricant coating layer on the surface of the sealant layer located in the innermost layer of the battery packaging material. By adopting these methods, the battery packaging material is easily drawn into the mold during molding, and cracks and pinholes in the battery packaging material can be suppressed.

  However, if the amount of the amide lubricant present on the surface of the sealant layer is too large, the amide lubricant adheres to the mold, and there is a problem that the mold is contaminated. When another battery packaging material is molded while the mold is contaminated, the lump of lubricant adhering to the mold adheres to the surface of the battery packaging material, and is directly used for heat sealing of the sealant layer. Then, when the sealant layer is heat-sealed, the melted portion of the portion to which the lubricant has adhered becomes non-uniform, resulting in a seal failure. In order to prevent this, it becomes necessary to increase the frequency of cleaning for removing the lubricant adhering to the mold, and there is a problem that the continuous productivity of the battery is lowered.

  On the other hand, when the amount of the amide-based lubricant located on the surface of the sealant layer is too small, the slipping property of the battery packaging material is lowered, and there is a problem that the moldability of the battery packaging material is lowered. Moreover, if the sliding property of the battery packaging material is low, troubles such as meandering and wrinkles are likely to occur when the battery packaging material is conveyed on the line, so that the continuous productivity of the battery also decreases in this case. There is a problem.

JP 2008-287971 A

In conventional battery packaging materials, an amide-based lubricant may be blended or coated on the sealant layer as described above. However, as a result of repeated studies by the present inventor, the amide-based lubricant was applied to the mold during the molding of the battery packaging material, despite the fact that the amide-based slip to be coated or blended in the sealant layer was set to a predetermined amount. It has been clarified that the continuous productivity is lowered due to the adhesion, and cracks and pinholes are generated in the battery packaging material and the moldability is lowered. As a result of further studies, even when an amide-based lubricant is used on the surface or inside of the sealant layer, if an adhesive layer is provided between the metal layer and the sealant layer, the moldability tends to decrease. I also found out.
Under such circumstances, an object of the present invention is to provide a battery packaging material having high moldability and excellent battery continuous productivity.

The present inventor has intensively studied to solve the above problems. As a result, in a battery packaging material comprising a laminate in which at least a base material layer, a metal layer, an adhesive layer, and a sealant layer are sequentially laminated, 10 to 30 mg / m ² of amide is formed on the surface of the sealant layer. It has been found that by forming a coating layer of the system lubricant, the moldability is improved by improving the slip property, and the adhesion of the lubricant to the mold or the like is suppressed to improve the continuous productivity of the battery. The present invention has been completed by further studies based on these findings.

That is, this invention provides the invention of the aspect hung up below.
Item 1. At least, it consists of a laminate in which a base material layer, a metal layer, an adhesive layer, and a sealant layer are sequentially laminated,
A battery packaging material in which a coating layer of 10 to 30 mg / m ^{2 of} an amide lubricant is formed on the surface of the sealant layer.
Item 2. Item 2. The battery packaging material according to Item 1, wherein the sealant layer contains an amide lubricant.
Item 3. Item 3. The battery packaging according to Item 1 or 2, wherein the amide-based lubricant forming the coating layer includes at least one selected from the group consisting of a saturated fatty acid amide having 21 or more carbon atoms, a saturated fatty acid bisamide, and a substituted amide. material.
Item 4. Item 4. The battery packaging material according to any one of Items 1 to 3, wherein the sealant layer contains a polyolefin resin.
Item 5. Item 5. The battery packaging material according to any one of Items 1 to 4, wherein the adhesive layer contains carboxylic acid-modified polypropylene.
Item 6. Item 6. The battery packaging material according to any one of Items 1 to 5, wherein the sealant layer has a thickness of 10 to 50 µm.
Item 7. Item 7. The battery packaging material according to any one of Items 1 to 6, wherein the adhesive layer has a thickness of 1 to 20 μm.
Item 8. Item 8. The battery packaging material according to any one of Items 1 to 7, wherein an adhesive layer is laminated between the base material layer and the metal layer.
Item 9. Item 9. The battery packaging material according to any one of Items 1 to 8, wherein the metal layer is formed of an aluminum foil.
Item 10. Item 10. The battery packaging material according to any one of Items 1 to 9, wherein a coating layer of a lubricant is formed on the surface of the base material layer 1.
Item 11. Item 11. A battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is accommodated in the battery packaging material according to any one of Items 1 to 10.

  According to the present invention, a battery packaging material having high moldability and excellent battery continuous productivity can be provided. Furthermore, according to this invention, the battery using the said packaging material for batteries can also be provided.

It is a figure which shows an example of the cross-section of the packaging material for batteries of this invention.

The battery packaging material of the present invention is composed of a laminate in which at least a base material layer, a metal layer, an adhesive layer, and a sealant layer are sequentially laminated, and the surface of the sealant layer has 10 to 30 mg / m ² . A coating layer of an amide type lubricant is formed. Hereinafter, the battery packaging material of the present invention will be described in detail.

1. Laminated Structure of Battery Packaging Material As shown in FIG. 1, the battery packaging material of the present invention comprises at least a laminate in which a base layer 1, a metal layer 3, an adhesive layer 5, and a sealant layer 4 are sequentially laminated. Become. In the battery packaging material of the present invention, the base material layer 1 is the outermost layer, and the sealant layer 4 is the innermost layer. That is, when the battery is assembled, the sealant layers 4 positioned at the periphery of the battery element are thermally welded to seal the battery element, thereby sealing the battery element. As shown in FIG. 1, the battery packaging material of the present invention is provided with an adhesive layer 2 between the base material layer 1 and the metal layer 3 as necessary for the purpose of enhancing the adhesion. Also good.

  As described above, due to the recent demand for smaller and thinner batteries, thinner packaging materials for batteries are required. The total thickness of the battery packaging material of the present invention is not particularly limited, but the battery packaging material has high formability and excellent battery continuous productivity while meeting the demand for further thinning. From the viewpoint of, it is preferably about 50 to 140 μm, more preferably about 60 to 120 μm.

2. Composition of each layer forming base material for battery [base material layer 1]
In the battery packaging material of the present invention, the base material layer 1 is a layer located in the outermost layer. The material for forming the base material layer 1 is not particularly limited as long as it has insulating properties. Examples of the material for forming the base material layer 1 include polyester, polyamide, epoxy resin, acrylic resin, fluorine resin, polyurethane, silicon resin, phenol resin, polyetherimide, polyimide, and a mixture or copolymer thereof. Can be mentioned.

  Specific examples of the polyester include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polycarbonate, copolymerized polyester mainly composed of ethylene terephthalate, butylene terephthalate as a repeating unit. Examples thereof include a copolymer polyester mainly used. The copolymer polyester mainly composed of ethylene terephthalate is a copolymer polyester that polymerizes with ethylene isophthalate mainly composed of ethylene terephthalate (hereinafter, polyethylene (terephthalate / isophthalate)). Abbreviated), polyethylene (terephthalate / isophthalate), polyethylene (terephthalate / adipate), polyethylene (terephthalate / sodium sulfoisophthalate), polyethylene (terephthalate / sodium isophthalate), polyethylene (terephthalate / phenyl-dicarboxylate) And polyethylene (terephthalate / decanedicarboxylate). In addition, as a copolymer polyester mainly composed of butylene terephthalate as a repeating unit, specifically, a copolymer polyester that polymerizes with butylene isophthalate having butylene terephthalate as a repeating unit (hereinafter referred to as polybutylene (terephthalate / isophthalate)). For example), polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate / decanedicarboxylate), polybutylene naphthalate and the like. These polyesters may be used individually by 1 type, and may be used in combination of 2 or more type. Polyester has the advantage of being excellent in electrolytic solution resistance and less likely to cause whitening due to the adhesion of the electrolytic solution, and is suitably used as a material for forming the base material layer 1.

  Specific examples of polyamides include aliphatic polyamides such as nylon 6, nylon 66, nylon 610, nylon 12, nylon 46, and copolymers of nylon 6 and nylon 6,6; terephthalic acid and / or Nylon 6I, Nylon 6T, Nylon 6IT, Nylon 6I6T (I represents isophthalic acid, T represents terephthalic acid) and the like, which include a structural unit derived from isophthalic acid, Aromatic polyamides such as silylene adipamide (MXD6); alicyclic polyamides such as polyaminomethylcyclohexyl adipamide (PACM6); and lactam components and isocyanate components such as 4,4′-diphenylmethane-diisocyanate. Polymerized polyamide, co-weight Polyester amide copolymer and polyether ester amide copolymer is a copolymer of polyamide and polyester and polyalkylene ether glycol; copolymers thereof, and the like. These polyamides may be used individually by 1 type, and may be used in combination of 2 or more type. The stretched polyamide film is excellent in stretchability, can prevent whitening due to resin cracking of the base material layer 1 during molding, and is suitably used as a material for forming the base material layer 1.

  The base material layer 1 may be formed of a uniaxially or biaxially stretched resin film, or may be formed of an unstretched resin film. Among them, a uniaxially or biaxially stretched resin film, in particular, a biaxially stretched resin film has improved heat resistance by orientation crystallization, and thus is suitably used as the base material layer 1. Moreover, the base material layer 1 may be formed by coating the above-mentioned raw material on the metal layer 3.

  Among these, as a resin film which forms the base material layer 1, Preferably nylon and polyester, More preferably, biaxially stretched nylon, biaxially stretched polyester, Most preferably, biaxially stretched nylon is mentioned.

  The base material layer 1 can also be laminated with at least one of resin films and coatings of different materials in order to improve pinhole resistance and insulation when used as a battery package. Specific examples include a multilayer structure in which a polyester film and a nylon film are laminated, and a multilayer structure in which a biaxially stretched polyester and a biaxially stretched nylon are laminated. When making the base material layer 1 into a multilayer structure, each resin film may be adhere | attached through an adhesive agent, and may be laminated | stacked directly without an adhesive agent. In the case of bonding without using an adhesive, for example, a method of bonding in a hot melt state such as a co-extrusion method, a sand lamination method, or a thermal laminating method can be mentioned. Moreover, when making it adhere | attach through an adhesive agent, the adhesive agent to be used may be a two-component curable adhesive, or a one-component curable adhesive. Further, the bonding mechanism of the adhesive is not particularly limited, and may be any of a chemical reaction type, a solvent volatilization type, a heat melting type, a hot pressure type, an electron beam curing type such as UV and EB, and the like. As an adhesive component, polyester resin, polyether resin, polyurethane resin, epoxy resin, phenol resin resin, polyamide resin, polyolefin resin, polyvinyl acetate resin, cellulose resin, (meth) acrylic resin Resins, polyimide resins, amino resins, rubbers, and silicone resins can be used.

  The base material layer 1 may have low friction in order to improve moldability. In the case of reducing the friction of the base material layer 1, the friction coefficient of the surface is not particularly limited, but for example, 1.0 or less can be mentioned. In order to reduce the friction of the base material layer 1, for example, mat treatment, formation of a coating layer of a lubricant, a combination thereof, and the like can be given.

  As the matting treatment, a matting agent is added to the base material layer 1 in advance to form irregularities on the surface, a transfer method by heating or pressurizing with an embossing roll, a surface is mechanically dry or wet blasting, or a file. There is a way to troll. Examples of the matting agent include fine particles having a particle size of about 0.5 nm to 5 μm. The material of the matting agent is not particularly limited, and examples thereof include metals, metal oxides, inorganic substances, and organic substances. The shape of the matting agent is not particularly limited, and examples thereof include a spherical shape, a fiber shape, a plate shape, an indeterminate shape, and a balloon shape. As a matting agent, specifically, talc, silica, graphite, kaolin, montmorilloid, montmorillonite, synthetic mica, hydrotalcite, silica gel, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, oxidation Aluminum, neodymium oxide, antimony oxide, titanium oxide, cerium oxide, calcium sulfate, barium sulfate, calcium carbonate, calcium silicate, lithium carbonate, calcium benzoate, calcium oxalate, magnesium stearate, alumina, carbon black, carbon nanotubes , High melting point nylon, crosslinked acrylic, crosslinked styrene, crosslinked polyethylene, benzoguanamine, gold, aluminum, copper, nickel and the like. These matting agents may be used individually by 1 type, and may be used in combination of 2 or more type. Among these matting agents, silica, barium sulfate, and titanium oxide are preferable from the viewpoint of dispersion stability and cost. The matting agent may be subjected to various surface treatments such as insulation treatment and high dispersibility treatment on the surface.

  The lubricant coating layer can be formed by depositing the lubricant on the surface of the base material layer 1 by bleeding out or by laminating the lubricant on the base material layer 1. The lubricant is not particularly limited. For example, amide lubricant, metal soap, hydrophilic silicone, silicone grafted acrylic, silicone grafted epoxy, silicone grafted polyether, silicone grafted polyester, block described below Type silicone acrylic copolymer, polyglycerol-modified silicone, paraffin and the like. These lubricants may be used individually by 1 type, and may be used in combination of 2 or more type.

  As thickness of the base material layer 1, 10-50 micrometers is mentioned, for example, Preferably 110-30 micrometers is mentioned.

[Adhesive layer 2]
In the battery packaging material of the present invention, the adhesive layer 2 is a layer provided as necessary in order to adhere the base material layer 1 and the metal layer 3.

  The adhesive layer 2 is formed of an adhesive capable of adhering the base material layer 1 and the metal layer 3. The adhesive used for forming the adhesive layer 2 may be a two-component curable adhesive or a one-component curable adhesive. Furthermore, the adhesive mechanism of the adhesive used for forming the adhesive layer 2 is not particularly limited, and may be any of a chemical reaction type, a solvent volatilization type, a heat melting type, a hot pressure type, and the like.

  Specific examples of the resin component of the adhesive that can be used to form the adhesive layer 2 include polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polycarbonate, and copolyester. Resin; Polyether adhesive; Polyurethane adhesive; Epoxy resin; Phenol resin resin; Polyamide resin such as nylon 6, nylon 66, nylon 12, copolymer polyamide; polyolefin, acid-modified polyolefin, metal-modified polyolefin, etc. Polyolefin resin; polyvinyl acetate resin; cellulose adhesive; (meth) acrylic resin; polyimide resin; urea resin, melamine resin and other amino resins; chloroprene rubber, nitrile rubber, styrene - rubbers such as butadiene rubber, silicone resin; fluorinated ethylene propylene copolymer, and the like. These adhesive components may be used individually by 1 type, and may be used in combination of 2 or more type. The combination mode of two or more kinds of adhesive components is not particularly limited. For example, as the adhesive component, a mixed resin of polyamide and acid-modified polyolefin, a mixed resin of polyamide and metal-modified polyolefin, polyamide and polyester, Examples thereof include a mixed resin of polyester and acid-modified polyolefin, and a mixed resin of polyester and metal-modified polyolefin. Among these, extensibility, durability under high-humidity conditions, anti-hypertensive action, thermal deterioration-preventing action during heat sealing, etc. are excellent, and a decrease in lamination strength between the base material layer 1 and the metal layer 3 is suppressed. From the viewpoint of effectively suppressing the occurrence of delamination, a polyurethane two-component curable adhesive; polyamide, polyester, or a blended resin of these with a modified polyolefin is preferable.

  The adhesive layer 2 may be multilayered with different adhesive components. When the adhesive layer 2 is multilayered with different adhesive components, from the viewpoint of improving the lamination strength between the base material layer 1 and the metal layer 3, the adhesive component disposed on the base material layer 1 side is used as the base material layer 1. It is preferable to select a resin having excellent adhesion to the metal layer 3 and to select an adhesive component having excellent adhesion to the metal layer 3 as the adhesive component disposed on the metal layer 3 side. When the adhesive layer 2 is multilayered with different adhesive components, specifically, the adhesive component disposed on the metal layer 3 side is preferably an acid-modified polyolefin, a metal-modified polyolefin, a polyester and an acid-modified polyolefin. And a resin containing a copolyester.

  About the thickness of the contact bonding layer 2, 2-50 micrometers, for example, Preferably 3-25 micrometers is mentioned.

[Metal layer 3]
In the battery packaging material of the present invention, the metal layer 3 is a layer that functions as a barrier layer for preventing the penetration of water vapor, oxygen, light, etc. into the battery, in addition to improving the strength of the packaging material. Specific examples of the metal forming the metal layer 3 include metal foils such as aluminum, stainless steel, and titanium. Among these, aluminum is preferably used. In order to prevent wrinkles and pinholes during the production of the packaging material, soft aluminum such as annealed aluminum (JIS A8021P-O) or (JIS A8079P-O) is used as the metal layer 3 in the present invention. Is preferred.

  About thickness of the metal layer 3, 10-200 micrometers is preferable, for example, Preferably it is 20-100 micrometers.

  Further, the metal layer 3 is preferably subjected to chemical conversion treatment on at least one surface, preferably at least the surface on the sealant layer 4 side, and more preferably both surfaces, for the purpose of stabilizing adhesion, preventing dissolution and corrosion, and the like. . Here, the chemical conversion treatment is a treatment for forming an acid-resistant film on the surface of the metal layer 3. Chemical conversion treatment is, for example, chromate chromate treatment using a chromic acid compound such as chromium nitrate, chromium fluoride, chromium sulfate, chromium acetate, chromium oxalate, chromium biphosphate, chromic acetyl acetate, chromium chloride, potassium sulfate chromium, etc. ; Phosphoric acid chromate treatment using phosphoric acid compounds such as sodium phosphate, potassium phosphate, ammonium phosphate, polyphosphoric acid; aminated phenol heavy consisting of repeating units represented by the following general formulas (1) to (4) Examples thereof include chromate treatment using a coalescence. In the aminated phenol polymer, the repeating units represented by the following general formulas (1) to (4) may be included singly or in any combination of two or more. Also good.

In general formulas (1) to (4), X represents a hydrogen atom, a hydroxyl group, an alkyl group, a hydroxyalkyl group, an allyl group or a benzyl group. R ¹ and R ² are the same or different and represent a hydroxyl group, an alkyl group, or a hydroxyalkyl group. In the general formulas (1) to (4), examples of the alkyl group represented by X, R ¹ and R ² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, C1-C4 linear or branched alkyl groups, such as a tert- butyl group, are mentioned. Examples of the hydroxyalkyl group represented by X, R ¹ and R ² include a hydroxymethyl group, a 1-hydroxyethyl group, a 2-hydroxyethyl group, a 1-hydroxypropyl group, a 2-hydroxypropyl group, 3- A linear or branched chain having 1 to 4 carbon atoms substituted with one hydroxy group such as hydroxypropyl group, 1-hydroxybutyl group, 2-hydroxybutyl group, 3-hydroxybutyl group, 4-hydroxybutyl group An alkyl group is mentioned. In the general formulas (1) to (4), X is preferably any one of a hydrogen atom, a hydroxyl group, and a droxyalkyl group. The number average molecular weight of the aminated phenol polymer composed of the repeating units represented by the general formulas (1) to (4) is, for example, about 500 to about 1,000,000, preferably about 1000 to about 20,000.

  In addition, as a chemical conversion treatment method for imparting corrosion resistance to the metal layer 3, a metal oxide such as aluminum oxide, titanium oxide, cerium oxide, tin oxide, or barium sulfate fine particles dispersed in phosphoric acid is coated. A method of forming a corrosion-resistant treatment layer on the surface of the metal layer 3 by performing a baking treatment at 150 ° C. or higher is mentioned. Moreover, you may form the resin layer which crosslinked the cationic polymer with the crosslinking agent on the corrosion-resistant process layer. Here, as the cationic polymer, for example, polyethyleneimine, an ionic polymer complex composed of a polymer having polyethyleneimine and a carboxylic acid, a primary amine-grafted acrylic resin in which a primary amine is grafted on an acrylic main skeleton, polyallylamine, or Examples thereof include aminophenols and derivatives thereof. These cationic polymers may be used individually by 1 type, and may be used in combination of 2 or more type. Examples of the crosslinking agent include compounds having at least one functional group selected from the group consisting of isocyanate groups, glycidyl groups, carboxyl groups, and oxazoline groups, silane coupling agents, and the like. These crosslinking agents may be used alone or in combination of two or more.

  These chemical conversion treatments may be performed alone or in combination of two or more chemical conversion treatments. Furthermore, these chemical conversion treatments may be carried out using one kind of compound alone, or may be carried out using a combination of two or more kinds of compounds. Among these, chromic acid chromate treatment is preferable, and chromate treatment in which a chromic acid compound, a phosphoric acid compound, and an aminated phenol polymer are combined is more preferable.

The amount of the acid-resistant film formed on the surface of the metal layer 3 in the chemical conversion treatment is not particularly limited. For example, if the chromate treatment is performed by combining a chromic acid compound, a phosphoric acid compound, and an aminated phenol polymer. The chromic acid compound is about 0.5 to about 50 mg, preferably about 1.0 to about 40 mg in terms of chromium, and the phosphorus compound is about 0.5 to about 50 mg in terms of phosphorus per 1 m ² of the surface of the metal layer 3. Is preferably about 1.0 to about 40 mg, and about 1 to about 200 mg, preferably about 5.0 to 150 mg of aminated phenol polymer.

  In the chemical conversion treatment, a solution containing a compound used for forming an acid-resistant film is applied to the surface of the metal layer 3 by a bar coating method, a roll coating method, a gravure coating method, a dipping method or the like, and then the temperature of the metal layer 3 is reached. Is performed by heating so as to be about 70 to 200 ° C. In addition, before the chemical conversion treatment is performed on the metal layer 3, the metal layer 3 may be subjected to a degreasing treatment by an alkali dipping method, an electrolytic cleaning method, an acid cleaning method, an electrolytic acid cleaning method, or the like in advance. By performing the degreasing treatment in this way, it becomes possible to more efficiently perform the chemical conversion treatment on the surface of the metal layer 3.

[Sealant layer 4]
In the battery packaging material of the present invention, the sealant layer 4 corresponds to the innermost layer, and is a layer that seals the battery element by heat-sealing the sealant layers when the battery is assembled.

  The sealant layer 4 is preferably formed of a polyolefin resin. The polyolefin resin is not particularly limited as long as it can be thermally welded, and examples thereof include polyolefin, cyclic polyolefin, carboxylic acid-modified polyolefin, and carboxylic acid-modified cyclic polyolefin.

  Specific examples of the polyolefin include polyethylene such as low density polyethylene, medium density polyethylene, high density polyethylene, and linear low density polyethylene; homopolypropylene, polypropylene block copolymer (for example, block copolymer of propylene and ethylene), polypropylene Polypropylenes such as random copolymers of (for example, random copolymers of propylene and ethylene); ethylene-butene-propylene terpolymers and the like. Among these polyolefins, polyethylene and polypropylene are preferable, and polypropylene is more preferable.

  The cyclic polyolefin is a copolymer of an olefin and a cyclic monomer, and examples of the olefin that is a constituent monomer of the cyclic polyolefin include ethylene, propylene, 4-methyl-1-pentene, styrene, butadiene, and isoprene. Is mentioned. Examples of the cyclic monomer that is a constituent monomer of the cyclic polyolefin include cyclic alkenes such as norbornene; specifically, cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, and norbornadiene. Among these polyolefins, cyclic alkene is preferable, and norbornene is more preferable.

  The carboxylic acid-modified polyolefin is a polymer obtained by modifying the polyolefin by block polymerization or graft polymerization with carboxylic acid. Examples of the carboxylic acid used for modification include maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, itaconic anhydride and the like.

  The carboxylic acid-modified cyclic polyolefin is obtained by copolymerizing a part of the monomer constituting the cyclic polyolefin in place of the α, β-unsaturated carboxylic acid or its anhydride, or α, β with respect to the cyclic polyolefin. -A polymer obtained by block polymerization or graft polymerization of an unsaturated carboxylic acid or its anhydride. The cyclic polyolefin to be modified with carboxylic acid is the same as described above. The carboxylic acid used for modification is the same as that used for modification of the acid-modified cycloolefin copolymer.

  Among these resin components, polyolefin and carboxylic acid-modified polyolefin are preferable, and polypropylene and carboxylic acid-modified polypropylene are more preferable.

  The sealant layer 4 may be formed of one kind of resin component alone, or may be formed of a blend polymer in which two or more kinds of resin components are combined. Furthermore, the sealant layer 4 may be formed of only one layer, but may be formed of two or more layers using the same or different resin components. As a preferable layer configuration when the sealant layer 4 is formed of two or more layers, for example, the outermost layer is formed of polypropylene and the layer on the metal layer 3 side is formed of carboxylic acid-modified polypropylene. Etc.

  The thickness of the sealant layer 4 can be selected as appropriate, and is about 10 to 100 μm, preferably about 15 to 50 μm.

In the battery packaging material of the present invention, a coating layer 4 a of 10 to 30 mg / m ² (dry weight) of amide-based lubricant is formed on the surface of the sealant layer 4. In the production of a battery, when the battery packaging material of the present invention is used for molding, an amide-based lubricant is present on the surface of the sealant layer 4 as the coating layer 4a. Thereby, the slipperiness of the surface of the sealant layer 4 is improved, and the moldability of the battery packaging material of the present invention is enhanced.

  As described above, even in conventional battery packaging materials, an amide-based lubricant is blended or coated in the sealant layer. However, as a result of investigation by the present inventor, the amide-based lubricant adheres to the mold during the molding of the battery packaging material even though the amide-based slip to be coated or blended in the sealant layer is set to a predetermined amount. As a result, it has been clarified that continuous productivity is reduced and cracks and pinholes may be generated in the battery packaging material. And in this case, both when the amide-based lubricant is blended in the sealant layer and when it is coated, the battery such as the storage environment, the transportation environment, etc. from the production of the battery packaging material to the molding is provided. It has been clarified that the amount of the amide-based lubricant located on the surface of the sealant layer is largely changed by the environment during the production from the packaging material to the molding, especially by the temperature change. For example, when the battery packaging material is exposed to a high temperature environment of 40 ° C. or higher, the saturation solubility of the amide-based lubricant in the sealant layer increases, so that the amide-based lubricant present on the surface of the sealant layer is contained inside the sealant layer. It is considered that the moldability of the sealant layer is lowered due to this. On the other hand, in order to prevent this, if the amount of the amide lubricant is increased, the amount of the amide lubricant present on the surface of the sealant layer becomes excessive when not exposed to a high temperature. There is a problem of adhering to the mold and contaminating the mold as a lump. Furthermore, even when an amide-based lubricant is used on the surface or inside of the sealant layer, it has also been clarified that if an adhesive layer is provided between the metal layer and the sealant layer, the moldability tends to be lowered. Therefore, for example, although the same amount of amide-based lubricant was used during the manufacture of battery packaging materials, the amount of amide-based lubricant located on the surface during molding changed greatly depending on the storage environment, etc. In some cases, the amide-based lubricant adheres to the product, resulting in a decrease in continuous productivity, or cracks or pinholes in the battery packaging material. It should be noted that the environment between the production of the battery packaging material from the production of the battery packaging material to the molding, such as the storage environment from the production of the battery packaging material to the time of molding and the transportation environment, in particular, the temperature change should be appropriately managed. For example, it is possible to suppress changes in the amount of amide-based lubricant between the production and molding of battery packaging materials, but in practice the storage environment and transport environment may not be properly managed. The problem of formability and continuous productivity may occur only after the molding.

On the other hand, in the battery packaging material of the present invention, a coating layer of a specific amount of an amide-based lubricant of 10 to 30 mg / m ² is formed on the surface of the sealant layer 4, so that the metal layer 3 and the sealant An adhesive layer is formed between the layer 4 and, when exposed to a high temperature, it has high moldability and is excellent in battery continuous productivity. The details of the mechanism by which the battery packaging material of the present invention exhibits such excellent effects are not clear, but can be considered as follows, for example. That is, in the battery packaging material of the present invention, a coating layer of a specific amount of amide-based lubricant of 10 to 30 mg / m ² is formed on the surface of the sealant layer 4, so that it is 40 ° C. or higher, and further 50 ° C. When the battery packaging material is stored and transported under the high temperature environment as described above, and the amide-based lubricant located on the surface of the sealant layer 4 moves into the sealant layer 4 and further into the adhesive layer 5. However, since a suitable amount of the amide-based lubricant remains on the surface of the sealant layer 4, it is considered that the decrease in the slipperiness of the sealant layer 4 in a high temperature environment is effectively suppressed.

The continuous production of moldability and battery of the battery packaging material of the present invention from the viewpoint of more effectively enhancing the surface of the sealant layer 4 is a coating layer of amide-based lubricant is formed about 15 to 25 mg / m ² It is preferable.

  In the present invention, the amide-based lubricant forming the coating layer 4a is not particularly limited, and examples thereof include fatty acid amide. Examples of fatty acid amides include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylol amides, saturated fatty acid bisamides, and unsaturated fatty acid bisamides. Specific examples of the saturated fatty acid amide include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, hydroxy stearic acid amide and the like. Specific examples of the unsaturated fatty acid amide include oleic acid amide and erucic acid amide. Specific examples of the substituted amide include N-oleyl palmitate, N-stearyl stearate, N-stearyl oleate, N-oleyl stearate, N-stearyl erucamide, and the like. Specific examples of methylolamide include methylol stearamide. Specific examples of saturated fatty acid bisamides include methylene bis stearamide, ethylene biscapric amide, ethylene bis lauric acid amide, ethylene bis stearic acid amide, ethylene bishydroxy stearic acid amide, ethylene bisbehenic acid amide, hexamethylene bis stearic acid amide. Examples include acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, N, N′-distearyl adipic acid amide, N, N′-distearyl sebacic acid amide, and the like. Specific examples of unsaturated fatty acid bisamides include ethylene bisoleic acid amide, ethylene biserucic acid amide, hexamethylene bisoleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide Etc. Specific examples of the fatty acid ester amide include stearoamidoethyl stearate. Specific examples of the aromatic bisamide include m-xylylene bis stearic acid amide, m-xylylene bishydroxy stearic acid amide, N, N′-cysteallyl isophthalic acid amide and the like.

  From the viewpoint of more effectively increasing the moldability of the battery packaging material of the present invention and the continuous productivity of the battery, the amide-based lubricant forming the coating layer 4a includes, among these, 21 or more carbon atoms such as behenamide. Saturated fatty acid amides, saturated fatty acid bisamides, substituted amides and the like are preferable, and behenic acid amide is particularly preferable.

  In the battery packaging material of the present invention, the sealant layer 4 may contain an amide lubricant. Examples of the amide-based lubricant that can be contained in the sealant layer 4 include the same ones as exemplified in the coating layer 4a. Among these, erucic acid amide is particularly preferable.

  When the amide type lubricant is contained in the sealant layer 4, the content thereof is preferably 300 ppm or more, more preferably about 300 to 900 ppm, on a mass basis.

[Adhesive layer 5]
In the battery packaging material of the present invention, the adhesive layer 5 is a layer provided between the metal layer 3 and the sealant layer 4 in order to firmly bond them.

  The adhesive layer 5 is formed of an adhesive capable of bonding the metal layer 3 and the sealant layer 4. With respect to the adhesive used for forming the adhesive layer 5, the adhesive mechanism, the types of adhesive components, and the like are the same as those of the adhesive layer 2. The adhesive component used for the adhesive layer 5 is preferably a polyolefin resin, more preferably a carboxylic acid-modified polyolefin, particularly preferably a carboxylic acid-modified polypropylene.

  About the thickness of the contact bonding layer 5, 2-50 micrometers, for example, Preferably it is 110-30 micrometers.

Conventionally, since the adhesive layer 5 positioned between the metal layer 3 and the sealant layer 4 is not a layer positioned on the surface of the battery packaging material, it is considered that the sliding property of the battery packaging material is not affected. It was. However, as a result of studies by the present inventors, even when an amide-based lubricant is blended in the sealant layer, if an adhesive layer exists between the metal layer and the sealant layer, the amide is applied from the inside or the surface of the sealant layer to the adhesive layer side. It was clarified that the amount of the amide-based lubricant present on the surface of the sealant layer was reduced by the migration of the lubricant. On the other hand, in the battery packaging material of the present invention, a coating layer of 10-30 mg / m ² of amide-based lubricant is formed on the surface of the sealant layer 4, so that it is 40 ° C. or higher, and further 50 ° C. When the battery packaging material is stored and transported under the high temperature environment as described above, and the amide-based lubricant located on the surface of the sealant layer 4 moves into the sealant layer 4 and further into the adhesive layer 5. However, since a suitable amount of the amide-based lubricant remains on the surface of the sealant layer 4, it is considered that the decrease in the slipperiness of the sealant layer 4 in a high temperature environment is effectively suppressed.

3. Method for Producing Battery Packaging Material The method for producing the battery packaging material of the present invention is not particularly limited as long as a laminate in which layers having a predetermined composition are laminated is obtained. For example, the following method is exemplified. .

  First, a laminate in which the base material layer 1, the adhesive layer 2, and the metal layer 3 are laminated in order (hereinafter also referred to as “laminate A”) is formed. Specifically, the laminate A is formed by extruding an adhesive used for forming the adhesive layer 2 on the base layer 1 or the metal layer 3 whose surface is subjected to chemical conversion treatment, if necessary. It can be performed by a dry lamination method in which the metal layer 3 or the base material layer 1 is laminated and the adhesive layer 2 is cured after being applied and dried by a coating method such as a method or a roll coating method.

  Next, the sealant layer 4 is laminated on the metal layer 3 of the laminate A via the adhesive layer 5. For example, (1) A method of laminating the adhesive layer 5 and the sealant layer 4 on the metal layer 3 of the laminate A by coextrusion (coextrusion lamination method), (2) Separately, the adhesive layer 5 and the sealant layer 4 Is formed by laminating the laminate on the metal layer 3 of the laminate A by a thermal lamination method, and (3) adhesion for forming the adhesive layer 5 on the metal layer 3 of the laminate A. A method of laminating a sealant layer 4 previously formed into a sheet on the adhesive layer 5 by a thermal lamination method, (4) a laminate; A method of laminating the laminate A and the sealant layer 4 via the adhesive layer 5 while pouring the molten adhesive layer 5 between the metal layer 3 of A and the sealant layer 4 previously formed into a sheet shape ( Sandra Mine (5) The adhesive used for forming the adhesive layer 5 is applied and dried onto the metal layer 3 by an extrusion method, a gravure coating method, a roll coating method or the like, and then the sealant layer. For example, a dry lamination method in which 4 is laminated to cure the adhesive layer 5 may be used.

Furthermore, the coating layer 4 a is formed by coating the surface of the sealant layer 4 with 10 to 30 mg / m ^{2 of} an amide lubricant. Moreover, you may provide the coating layer of a lubricant etc. on the surface of the base material layer 1 as needed as mentioned above. In addition, in order to strengthen the adhesiveness of the adhesive layer 2 and the adhesive layer 5 provided as necessary, it may be further subjected to a heat treatment such as a hot roll contact type, a hot air type, a near or far infrared type. Examples of such heat treatment conditions include 150 to 250 ° C. for 1 to 5 minutes.

  In the battery packaging material of the present invention, each layer constituting the laminate improves or stabilizes film forming properties, lamination processing, suitability for final processing (pouching, embossing), etc., as necessary. Therefore, surface activation treatment such as corona treatment, blast treatment, oxidation treatment, ozone treatment may be performed.

4). Application of Battery Packaging Material The battery packaging material of the present invention is used as a packaging material for sealing and housing battery elements such as a positive electrode, a negative electrode, and an electrolyte.

  Specifically, a battery element including at least a positive electrode, a negative electrode, and an electrolyte is formed using the battery packaging material of the present invention, with the metal terminals connected to each of the positive electrode and the negative electrode protruding outward. A battery using a battery packaging material is formed by covering the periphery of the element so that a flange portion (a region where the sealant layers are in contact with each other) can be formed, and heat-sealing and sealing the sealant layers of the flange portion. Provided. In addition, when accommodating a battery element using the battery packaging material of the present invention, the battery packaging material of the present invention is used such that the sealant portion is on the inner side (surface in contact with the battery element).

  The battery packaging material of the present invention may be used for either a primary battery or a secondary battery, but is preferably a secondary battery. The type of secondary battery to which the battery packaging material of the present invention is applied is not particularly limited. For example, a lithium ion battery, a lithium ion polymer battery, a lead battery, a nickel / hydrogen battery, a nickel / cadmium battery , Nickel / iron livestock batteries, nickel / zinc livestock batteries, silver oxide / zinc livestock batteries, metal-air batteries, polyvalent cation batteries, capacitors, capacitors and the like. Among these secondary batteries, lithium ion batteries and lithium ion polymer batteries are suitable applications for the battery packaging material of the present invention.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

Examples 1-6 and Comparative Examples 1-4
<Manufacture of battery packaging materials>
Chemical conversion treatment is performed on both surfaces of an aluminum foil (thickness 40 μm) as a metal layer, and a nylon film is applied as a base material layer (thickness 25 μm) on one chemical conversion treatment surface so that the thickness of the adhesive layer is about 3 μm. Were bonded together by a dry laminating method through a polyester adhesive. Next, in Examples 1 to 3 and Comparative Examples 1 and 2, an amide-based lubricant is used so that the chemical conversion treatment surface of the other aluminum foil has an adhesive layer (thickness of 23 μm) and the content shown in Table 1. A polyolefin resin forming a sealant layer (thickness: 23 μm) blended with A was coextruded to obtain a laminate composed of a base material layer / adhesive layer / aluminum foil / adhesive layer / sealant layer. On the other hand, in Examples 4 to 6 and Comparative Examples 3 and 4 , the content shown in Table 1 was applied to the other chemical conversion treated surface of the aluminum foil by an adhesive layer (thickness 4 μm) by a dry laminating method. A polyolefin resin for forming a sealant layer (thickness: 23 μm) containing an amide lubricant was laminated. Next, the coating layer of the amide lubricant B is formed on the surface of the sealant layer so as to have the thickness shown in Table 1, and the base layer / adhesive layer / aluminum foil / adhesive layer / sealant layer / coating layer is formed. A laminate comprising:

Each battery packaging material was manufactured at a temperature of 25 ° C. and a relative humidity of 50%. In each of the chemical conversion treatments, an aqueous solution composed of a phenol resin, a chromium fluoride compound, and phosphoric acid was used as a treatment solution, applied by a roll coating method, and baked under conditions where the film temperature was 180 ° C. or higher. The amount of chromium applied was 10 mg / m ² (dry weight). The amide type lubricants used are as follows.
Amide lubricant A: erucic acid amide Amide lubricant B: Behenamide

Examples 7 to 9 and Comparative Example 5
<Manufacture of battery packaging materials>
Coating layer / base material layer / adhesion in the same manner as in Examples 1 to 3 and Comparative Examples 1 and 2 except that a coating layer of 10 mg / m ² (dry weight) of lubricant was provided on the surface of the base material layer. A laminate composed of layer / aluminum foil / adhesive layer / sealant layer / coating layer was obtained. On the surface of the base material layer, ethylene bisoleic acid amide was used as a lubricant.

(Storage at 40 ° C or 50 ° C)
The battery packaging materials of Examples 1 to 9 and Comparative Examples 1 to 5 were left at a temperature of 40 ° C. or a temperature of 50 ° C. for 7 days under a relative humidity of 50%, respectively, and then subjected to the following friction test and moldability test. A white powder confirmation test was conducted.

(Friction test)
The friction test was measured by a method according to JIS K7125. First, each battery packaging material obtained above was cut into 80 × 200 mm samples. Next, the samples were stacked so that the surfaces of the sealant layer were opposed to each other, and a weight (200 g) was placed thereon. Rubber was attached to the bottom of the weight stone, and the sample and the weight stone were in close contact with each other to prevent slipping. Next, the weight was pulled at a speed of 100 mm / min, the dynamic friction force (N) was measured, and the dynamic friction coefficient was calculated by dividing the dynamic friction force by the normal force (1.96 N) of the weight. The obtained results were evaluated according to the following criteria. The results are shown in Table 1.
○: Dynamic friction coefficient is 0.3 or less Δ: Dynamic friction coefficient is more than 0.3, 0.7 or less ×: Dynamic friction coefficient is more than 0.7

(Formability test)
Each battery packaging material obtained above was cut into 80 × 120 mm square to prepare samples. Using a forming mold (female mold) having a diameter of 30 × 50 mm and a molding mold (male mold) corresponding to the sample, a pressing pressure of 0.4 MPa and a molding depth of 0.5 mm to 0.5 mm are used. Cold forming was performed on each of 10 samples at different forming depths in units of 5 mm. For the samples after cold forming, the deepest forming depth at which pinholes and cracks did not occur in all 10 samples of the wrinkles and aluminum foil was defined as the limit forming depth of the sample. From this limit molding depth, the moldability of the battery packaging material was evaluated according to the following criteria. The results are shown in Table 1.
○: Limit forming depth 6.0 mm or more Δ: Limit forming depth 4.0 mm to 5.5 mm
×: Limit molding depth 3.5mm or less

(White powder confirmation test)
Fold black paper cut into 5 x 13 cm in half and attach white powder (bleed-out lubricant) by strongly rubbing the sealant surface of each battery packaging material obtained above with a predetermined area (1 m ² ). The degree was confirmed visually. The obtained results were evaluated according to the following criteria. The results are shown in Table 1.
○: Almost no adhesion △: Slight adhesion ×: Adhesion is conspicuous

As is clear from the results shown in Table 1, in the battery packaging materials of Examples 1 to 9 in which a coating layer of amide type lubricant of 10 to 30 mg / m ² is provided on the surface of the sealant layer, the temperature is 40 ° C. or 50 ° C. Even when stored at a high temperature, there were no problems in practical use in all of the friction test, the moldability test, and the white powder confirmation test.
On the other hand, the battery packaging materials of Comparative Examples 1 and 3, in which only 5 ml / m ² of the amide lubricant was blended only in the sealant layer, were inferior in friction test or moldability when stored at a high temperature of 40 ° C. or 50 ° C. . Further, in the battery packaging material of Comparative Example 2, 4, 5 the amide-based lubricant only to the sealant layer was 40 mg / m ² formulation, when stored at a high temperature of 40 ° C. or 50 ° C., is inferior confirmation test white powder It was.

DESCRIPTION OF SYMBOLS 1 Base material layer 2 Adhesive layer 3 Metal layer 4 Sealant layer 4a Coating layer 5 of an amide type lubricant 5 Adhesive layer

Claims (11)

At least, it consists of a laminate in which a base material layer, a metal layer, an adhesive layer, and a sealant layer are sequentially laminated,
The sealant layer contains an amide lubricant, and
A battery packaging material in which a coating layer of 10 to 30 mg / m ^{2 of} an amide lubricant is formed on the surface of the sealant layer. The battery packaging material according to claim 1 , wherein the amide-based lubricant forming the coating layer is different from the amide-based lubricant contained in the sealant layer .   The battery for battery according to claim 1 or 2, wherein the amide-based lubricant forming the coating layer contains at least one selected from the group consisting of a saturated fatty acid amide having 21 or more carbon atoms, a saturated fatty acid bisamide, and a substituted amide. Packaging material.   The battery packaging material according to claim 1, wherein the sealant layer contains a polyolefin resin.   The battery packaging material according to claim 1, wherein the adhesive layer contains carboxylic acid-modified polypropylene.   The battery packaging material according to claim 1, wherein the sealant layer has a thickness of 10 to 50 μm.   The battery packaging material according to claim 1, wherein the adhesive layer has a thickness of 1 to 30 μm.   The battery packaging material according to any one of claims 1 to 7, wherein an adhesive layer is laminated between the base material layer and the metal layer.   The battery packaging material according to any one of claims 1 to 8, wherein the metal layer is formed of an aluminum foil.   The battery packaging material according to claim 1, wherein a coating layer of a lubricant is formed on the surface of the base material layer 1. The battery by which the battery element provided with the positive electrode, the negative electrode, and electrolyte at least is accommodated in the packaging material for batteries in any one of Claims 1-10.