JP2009238475A - Outer package for battery, and battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an outer package for a battery superior in electrolytic liquid resistance, leakage resistance, and water resistance, and a battery using the outer package. <P>SOLUTION: The outer package for the battery includes a substrate layer, barrier layer, anchor layer, sealant layer, and adhesive layer laminated in this order, and the anchor layer and the adhesive layer contains an acid denatured polyolefin resin containing a (meth) acrylic acid ester component. Furthermore, the coating weight of the anchor layer and the adhesive layer is in the range 0.001-5 g/m<SP>2</SP>. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a battery case and a battery using the case.

  2. Description of the Related Art In recent years, lithium batteries that can be made extremely thin and small have been actively developed as batteries used in portable terminal devices such as personal computers and mobile phones, video cameras, and satellites. Unlike the metal cans that have been used in the past, this lithium battery exterior material is lightweight and has a structure such as a base material layer / aluminum foil layer / sealant layer because of the advantage that the battery shape can be freely selected. The body has come to be used.

Lithium battery is impregnated with electrolyte solution or lithium electrolyte dissolved in aprotic solvent such as propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate together with positive electrode material and negative electrode material as battery contents And an electrolyte layer made of a polymer gel. When such a strong permeable solvent passes through the sealant layer, the laminate strength between the aluminum foil layer and the sealant layer is lowered to cause delamination, and finally the electrolyte leaks. Lithium salt, which is the battery electrolyte, uses LiPF ₆ , LiBF _4, etc., but these salts generate hydrofluoric acid by hydrolysis with water, and the hydrofluoric acid corrodes the aluminum foil. By doing so, the laminate strength is lowered. Thus, the battery exterior material needs to have resistance to the electrolyte.

  Furthermore, the lithium battery needs to have more severe resistance assuming that it is used in various environments. For example, when used in a mobile device, liquid leakage resistance in a high temperature environment of 60 to 70 ° C. such as in a car is required. In addition, water resistance is also required to prevent moisture from entering, assuming that it was used in a mobile phone and accidentally dropped into water.

Under such circumstances, various exterior materials for lithium batteries having improved electrolyte resistance have been proposed (Patent Documents 1 to 4).
Japanese Patent Laid-Open No. 2001-243928 JP 2004-42477 A JP 2004-142302 A JP 2002-187233 A

  However, all of the proposed packaging materials for lithium batteries are insufficient in terms of leakage resistance and water resistance.

  The subject of this invention is providing the battery using the exterior body for batteries which is excellent also in leakage resistance and water resistance with electrolyte solution resistance, and the said exterior body.

  That is, in the present invention, a base material layer, a barrier layer, an anchor layer, a sealant layer, and an adhesive layer are laminated in this order, and the anchor layer and the adhesive layer contain an (meth) acrylic acid ester component. It is the battery exterior body characterized by including this, Moreover, it is a battery using the said exterior body.

  The battery outer body of the present invention is a battery outer body in which an aluminum foil layer, an anchor layer, a sealant layer, and an adhesive layer are sequentially laminated on one surface of a base material layer. By using the resin, it exhibits excellent electrolytic solution resistance, leakage resistance and water resistance when used as a battery outer package. For this reason, the life of the battery is extended, the safety in handling is increased, and the industrial utility value is very high.

  Moreover, according to the manufacturing method of this invention, since the fabric weight of the acid-modified polyolefin resin laminated | stacked as an anchor layer and an adhesion layer is easy to adjust, and it is easy to control thickness thinly, it can produce efficiently. Moreover, since an aqueous dispersion is used, it is preferable also from an environmental viewpoint.

  The battery exterior body of this invention has the structure which laminated | stacked the base material layer, the barrier layer, the anchor layer, the sealant layer, and the contact bonding layer in this order in the thickness direction.

  The base material layer is composed of a single-layer or multilayer heat-resistant polymer film, for example, a single film such as a stretched or unstretched film such as a polyester film, a polyamide film, or a polypropylene film, or a multilayer film in which the single films are laminated. Can be used. In order to improve pinhole resistance and insulation, the total thickness is preferably 6 to 40 μm, more preferably 10 to 25 μm.

A primer layer can be provided between the base material layer and the barrier layer as necessary. The primer layer, silane coupling agent or a polyester polyol or polyether polyol, and comprise polyurethane adhesive as main agent an acrylic polyol, the coating amount is preferably set to 1 to 5 g / m ² in a dry state.

  As the barrier layer, a vapor-deposited layer obtained by vapor-depositing alumina or silica, an aluminum foil, or the like can be used, but an aluminum foil is preferably used from the viewpoint of barrier properties.

  When an aluminum foil is used, a soft aluminum foil having a thickness of 9 to 200 μm, in particular, a soft aluminum foil having an iron content of 0.1 to 9.0% by mass is resistant to pinholes and stretchability at the time of molding. Is preferable. If the iron content is less than 0.1% by mass, sufficient pinhole resistance and ductility cannot be imparted, and if it exceeds 9.0% by mass, flexibility may be impaired.

  In the case of using a soft aluminum foil, it is preferable to perform a known surface treatment on the surface on which the anchor layer is laminated in order to improve the adhesion with the anchor layer, and hot water such as a degreasing treatment with an acid degreasing agent or a boehmite treatment. It is preferable to perform a chemical conversion treatment such as a modification treatment, an anodizing treatment such as alumite treatment, or a chromate treatment. An example of a particularly preferred surface treatment is a method of treating with a fluorine-containing compound such as monosodium ammonium difluoride dissolved in an inorganic acid with an acid degreasing agent. In addition to the degreasing effect of a soft aluminum foil, It is possible to form a certain aluminum fluoride, which is effective in terms of resistance to hydrofluoric acid.

  The battery outer body of the present invention includes an acid-modified polyolefin resin containing a (meth) acrylic acid ester component as an anchor layer and an adhesive layer. The same acid-modified polyolefin resin may be used for the anchor layer and the adhesive layer, or different acid-modified polyolefin resins may be used for the respective layers.

  The olefin component that is the main component of the acid-modified polyolefin resin is not particularly limited, but an alkene having 2 to 6 carbon atoms such as ethylene, propylene, isobutylene, 2-butene, 1-butene, 1-pentene, 1-hexene is preferable, Mixtures of these may be used. Among these, alkene having 2 to 4 carbon atoms such as ethylene, propylene, isobutylene and 1-butene is more preferable, ethylene and propylene are further preferable, and ethylene is most preferable.

  The acid-modified polyolefin resin is acid-modified with an unsaturated carboxylic acid component. Examples of unsaturated carboxylic acid components include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, and the like, as well as unsaturated dicarboxylic acid half esters and half amides. It is done. Of these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable. The unsaturated carboxylic acid component only needs to be copolymerized in the acid-modified polyolefin resin, and the form thereof is not limited. Examples of the copolymerization state include random copolymerization, block copolymerization, and graft copolymerization. (Graft modification) and the like.

  The content of the unsaturated carboxylic acid component in the acid-modified polyolefin resin is preferably 0.01 to 10% by mass, more preferably 0.1 to 5% by mass, from the balance of adhesion between the barrier layer and the sealant layer. 0.5-4 mass% is further more preferable, and 1-4 mass% is especially preferable. When the content is less than 0.01 mass, sufficient adhesion with a barrier layer such as an aluminum foil may not be obtained. Moreover, when it exceeds 10 mass%, adhesiveness with a sealant layer may fall.

  The acid-modified polyolefin resin needs to contain a (meth) acrylic acid ester component. If this component is not contained, sufficient adhesion to the barrier layer or sealant layer cannot be obtained. Examples of the (meth) acrylic acid ester component include an esterified product of (meth) acrylic acid and an alcohol having 1 to 30 carbon atoms, and (meth) acrylic acid and carbon number 1 from the viewpoint of easy availability. Esterified products with ˜20 alcohols are preferred. Specific examples of the (meth) acrylic acid ester component include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, (meth ) Octyl acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, and the like. Mixtures of these may be used. Among these, from the viewpoint of easy availability and adhesiveness, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl acrylate, octyl acrylate are more preferable, ethyl acrylate, More preferred is butyl acrylate, and particularly preferred is ethyl acrylate. ("(Meth) acrylic acid" means "acrylic acid or methacrylic acid".)

  The content of the (meth) acrylic acid ester component in the acid-modified polyolefin resin is preferably from 0.1 to 25% by mass, more preferably from 1 to 20% by mass, from the viewpoint of improving content resistance. 2 to 18% by mass is more preferable. When the content of the (meth) acrylic acid ester component is less than 0.1% by mass, the adhesiveness to the aluminum foil or the polyolefin resin film tends to decrease, and when it exceeds 25% by mass, the content resistance decreases. Resulting in. Further, the (meth) acrylic acid ester component may be copolymerized in the acid-modified polyolefin resin, and the form thereof is not limited. Examples of the copolymerization state include random copolymerization, block copolymerization, and grafting. Examples include copolymerization (graft modification).

  As a specific example of the acid-modified polyolefin resin, an ethylene- (meth) acrylic acid ester-maleic anhydride copolymer is most preferable. The form of the copolymer may be any of a random copolymer, a block copolymer, a graft copolymer, etc., but a random copolymer and a graft copolymer are preferred from the viewpoint of easy availability.

Basis weight of the anchor layer and the adhesive layer, the area of the bonding surface, is preferably in the range of 0.001 to 5 g / ^{m 2,} more preferably from 0.01 to 3 g / ^{m 2,} 0 further preferably .02~2g / ^{m 2,} particularly preferably from 0.03~1g / ^{m 2,} and most preferably 0.05 to 1 g / ^{m 2.} If the anchor layer is less than 0.001 g / m ² , the adhesion to the barrier layer may be insufficient, and if the adhesion layer is less than 0.001 g / m ² , the adhesion of the battery tab portion is particularly insufficient. There is a fear. In addition, when both the anchor layer and the adhesive layer exceed 5 g / m ² , not only is it economically disadvantageous, but also lithium salt is decomposed by moisture permeating from the end face to generate hydrofluoric acid, which deteriorates battery performance. There is a risk.

  Regarding the acid-modified polyolefin resin used for the anchor layer and the adhesive layer, the higher the molecular weight, the better the electrolytic solution resistance. The melt flow rate at 190 ° C. and 2160 g load, which is a measure of molecular weight, is preferably 100 g / min or less, more preferably 30 g / min or less, further preferably 0.001 to 20 g / 10 min, and 0.01 to 10 g / 10 Minutes are particularly preferred. If the melt flow rate exceeds 100 g / min, the resistance to physical properties tends to decrease, and if it is less than 0.001 g / min, there are restrictions on the production surface when the resin is made high molecular weight.

  The acid-modified polyolefin resin may contain other resin at 20% by mass or less. For example, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, ethylene- (meth) acrylic acid copolymer, styrene-maleic acid resin, styrene-butadiene resin, butadiene resin, acrylonitrile-butadiene Examples include resins, poly (meth) acrylonitrile resins, (meth) acrylamide resins, chlorinated polyethylene resins, chlorinated polypropylene resins, polyester resins, modified nylon resins, urethane resins, phenol resins, silicone resins, and epoxy resins.

  The acid-modified polyolefin resin may contain a crosslinking agent. Examples of the crosslinking agent include isocyanate compounds, melamine compounds, urea compounds, epoxy compounds, carbodiimide compounds, oxazoline group-containing compounds, aziridine compounds, zirconium salt compounds, silane coupling agents, and the like. These contents may be appropriately determined in consideration of the resistance to electrolytic solution.

  A known sealant resin can be used for the sealant layer of the exterior body of the present invention. For example, polyester elastomer, polyurethane elastomer, polyethylene such as low density polyethylene (LDPE) and high density polyethylene (HDPE), acid-modified polyethylene, polypropylene, Examples include acid-modified polypropylene, copolymerized polypropylene, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid ester copolymer, ethylene- (meth) acrylic acid copolymer, and polyolefin resins such as ethylene ionomers. Among them, an olefin resin is preferable from the viewpoint of resistance to electrolytic solution, a polyethylene resin is more preferable from the viewpoint of low-temperature sealability, and polyethylene is particularly preferable because it is inexpensive.

  The thickness of the sealant layer of the present invention is preferably 0.1 to 500 μm, more preferably 1 to 100 μm, further preferably 5 to 80 μm, and particularly preferably 10 to 50 μm. If the thickness of the sealant is less than 0.1 μm, the adhesiveness may be insufficient when the power generating element is sealed by heat sealing, and if it exceeds 500 μm, it is not preferable because it is economically disadvantageous.

  The method of providing the sealant layer is not particularly limited, but the method of bonding the sealant film made of the sealant resin and the anchor layer by heat (thermal lamination, dry lamination) or the method of extruding and bonding the resin melted in the anchor layer (Extrusion lamination).

  In the present invention, the method for providing the anchor layer and the adhesive layer is not particularly limited. For example, the acid-modified polyolefin resin is dissolved or dispersed to form a coating agent, which is applied to the barrier layer or sealant layer, and the medium is dried. A method in which a coating layer in which an acid-modified polyolefin resin is dissolved or dispersed is applied onto a release paper, and a resin layer obtained by drying the medium is transferred onto a barrier layer or a sealant layer. Examples thereof include a method of melt extrusion onto a layer or a sealant layer. Among these, from the viewpoint of environmental and performance, a method of applying a coating agent (aqueous dispersion) in which an acid-modified polyolefin resin is dissolved or dispersed in an aqueous medium to the barrier layer or the sealant layer and drying the medium, It is preferable because the basis weight of the acid-modified polyolefin resin layer, that is, the anchor layer and the adhesive layer can be easily adjusted, and in particular, the thickness can be easily controlled thinly.

  When using an aqueous dispersion, the aqueous dispersion is applied to the barrier layer, dried to form an anchor layer, and then the sealant layer is laminated by melt extrusion (extrusion lamination) of the sealant resin in-line. A method of applying an aqueous dispersion on a sealant layer and drying to form an adhesive layer, or applying an aqueous dispersion on both sides of the sealant film and drying to form an anchor layer and an adhesive layer, and providing the sealant film A method of thermally bonding the anchor layer to the barrier layer is simple and particularly preferable.

  Examples of the aqueous dispersion of the acid-modified polyolefin resin suitable for the above method include those described in International Publication No. 02/055598.

  In the case of using an aqueous dispersion, known application methods such as gravure roll coating, reverse roll coating, wire bar coating, lip coating, air knife coating, curtain flow coating, spray coating, dip coating, and brush coating are used. Coat the surface of the substrate evenly by setting, etc., and set it near room temperature as necessary, then subject it to drying treatment or heat treatment for drying to form a uniform resin layer in close contact with the coated surface Can do.

  In the case of using an aqueous dispersion, it is preferable to use an emulsifier or a compound having a protective colloid action as little as possible, and most preferably not to use, in order not to deteriorate the content resistance.

  The battery outer body of the present invention is combined with a power generation element to constitute a battery. The power generation element is composed of a positive electrode composed of a positive electrode active material and a current collector, a separator, a negative electrode composed of a negative electrode active material and a current collector, and an electrolytic solution, and each of the positive electrode and the negative electrode has a tab extended at an end.

The constituent material of the power generation element is not particularly limited, and a known power generation element can be used. Examples of the positive electrode active material include lithium salts such as lithium manganate and metallic lithium, and examples of the positive electrode current collector include aluminum foil. Examples of the separator include polyethylene and polypropylene microporous membranes. Examples of the negative electrode active material include graphite, lithium salts such as lithium manganate, metallic lithium, and the like are used. Examples of the positive electrode current collector include aluminum foil. As the electrolyte, lithium salts such as lithium tetrafluoroborate (LiBF ₄ ) and lithium hexafluorophosphate (LiPF ₆ ) can be used as ethyl carbonate (EC), ethyl methyl carbonate (EMC), propylene carbonate, etc. What was melt | dissolved is mentioned.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.
(1) Configuration of acid-modified polyolefin resin
^It calculated | required from < ¹ > H-NMR analysis (The product made by Varian, 300MHz). Orthodichlorobenzene (d ₄ ) was used as a solvent, and measurement was performed at 120 ° C.
(2) Melt flow rate (MFR) of acid-modified polyolefin resin
It measured by the method of JIS6730 description (190 degreeC, 2160g load).
(3) Weight per unit area A predetermined amount of an aqueous dispersion of acid-modified polyolefin resin was applied to a substrate whose area and mass were measured in advance, and dried at 100 ° C. for 2 minutes. The mass of the obtained laminate was measured, and the coating amount was determined by subtracting the mass of the base material before coating. The basis weight (g / m ² ) was calculated from the coating amount and the coating area.
(4) Electrolytic solution resistance The produced exterior body was cut into a size of 100 × 15 mm to obtain a test piece. The test piece was inserted into a container filled with an electrolytic solution and sealed, and stored at 85 ° C. for 3 hours and further immersed in water for one day and night. The case where peeling was not recognized was rated as ◯, and the case where peeling was recognized was marked as x. Incidentally, the electrolytic solution was used a solution LiPF ₆ in solution was adjusted to 1.5M of ethylene carbonate / diethyl carbonate / dimethyl carbonate = 1/1/1 (mass ratio).
(5) Water resistance The produced exterior body was cut | judged to the dimension of 100x15 mm, and it was set as the test piece, and the peeling condition of the test piece after immersing the test piece in 85 degreeC water for one day and night was observed visually. The case where peeling was not recognized was rated as ◯, and the case where peeling was recognized was marked as x.
(6) Liquid leakage resistance The produced battery was put into a 50 degreeC dryer, and liquid leakage resistance was investigated. The case where leakage of the electrolytic solution was not recognized was rated as “◯”, and the case where leakage of the electrolytic solution was recognized was marked as “X”.

Reference example 1
[Production of acid-modified polyolefin resin aqueous dispersion E-1]
Using a stirrer equipped with a hermetically sealed 1 liter glass container with a heater, 60.0 g acid-modified polyolefin resin (Arkema Bondine TX-8030), 90.0 g isopropanol, 3.0 g triethylamine and When 147.0 g of distilled water was charged into a glass container and stirred at a rotation speed of the stirring blade of 300 rpm, no precipitation of resin particles was observed at the bottom of the container, and it was confirmed that the container was in a floating state. . Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 140 to 145 ° C. and further stirred for 30 minutes. Then, after putting in a water bath and cooling to room temperature (about 25 ° C.) while stirring at a rotational speed of 300 rpm, pressure filtration (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) As a result, a milky white uniform acid-modified polyolefin resin aqueous dispersion E-1 was obtained. The solid content concentration of E-1 was 20.0% by mass.

Reference example 2
[Production of acid-modified polyolefin resin aqueous dispersion E-2]
Bondin HX-8290 (manufactured by Arkema) was used as the acid-modified polyolefin resin, and the same operation as in the production of the aqueous dispersion E-1 was performed to obtain an acid-modified polyolefin resin aqueous dispersion E-2. The solid content concentration of E-2 was 20.0% by mass.

Reference example 3
[Production of acid-modified polyolefin resin aqueous dispersion E-3]
Using a stirrer equipped with a hermetically sealed 1 liter glass container equipped with a heater, 60.0 g ethylene-acrylic acid copolymer resin (Primacol 5980I manufactured by Dow Chemical Company), 16.8 g TEA, and 223 When 2 g of distilled water was charged into a glass container and stirred at a rotation speed of the stirring blade of 300 rpm, no sedimentation of resin particles was observed at the bottom of the container, confirming that it was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 140 to 145 ° C. and further stirred for 30 minutes. Then, after putting in a water bath and cooling to room temperature (about 25 ° C.) while stirring at a rotational speed of 300 rpm, pressure filtration (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) As a result, a slightly cloudy aqueous dispersion E-3 was obtained. The solid content concentration of E-3 was 20.1% by mass.

  Table 1 shows the composition of the acid-modified polyolefin resin used for the production of the aqueous dispersions E-1 to E-3.

Example 1
A biaxially stretched polyester resin film ("Embret PET-12" manufactured by Unitika Ltd.) with a thickness of 12 μm is used, and a two-component curing type polyurethane adhesive (manufactured by Toyo Morton Co., Ltd.) on the corona-treated surface of the polyester resin film as a primer. ) Is dried after gravure coating so that the coating amount after drying is 5 g / m ² , and both sides of a 40 μm thick soft aluminum foil (8079 material, Toyo Aluminum Co., Ltd., trade name: CE) are used as a barrier layer. A barrier base material to which the acid degreased material was bonded was obtained. Next, a 10% diluted solution of the acid-modified polyolefin resin aqueous dispersion E-1 was applied to the aluminum foil surface of the barrier base material so that the coating amount after drying was 0.7 g / m ^2, and ² at 100 ° C. An anchor layer was formed by drying for a minute.

Next, using a laminator equipped with an extruder, LDPE (L211 manufactured by Sumitomo Chemical Co., Ltd.) was melt-extruded as a sealant resin on the surface of the adhesive layer to form a sealant layer composed of a 30 μm LDPE layer. Further, a 10% diluted solution of acid-modified polyolefin resin aqueous dispersion E-1 was applied onto the sealant layer so that the coating amount after drying was 0.7 g / m ^2, and dried at 100 ° C. for 2 minutes for adhesion. A layer was formed to obtain an outer package.

On the other hand, a paste prepared by mixing lithium manganate and E-1 in a solid content mass ratio of 90/10 on a 40 μm aluminum foil was applied to a thickness of 30 μm after drying, and dried to a thickness of 50 mm. A positive electrode of × 100 mm was obtained. A paste prepared by mixing graphite and E-1 on a 40 μm copper foil so as to have a solid content mass ratio of 90/10 was coated to a thickness of 30 μm after drying, and dried to form a negative electrode of 50 mm × 100 mm. Obtained. For drying, both the positive electrode and the negative electrode were dried at 85 ° C. for 30 minutes and then dried under reduced pressure at 120 ° C. for 12 hours. Exterior body with 90 mm × 150 mm adhesive layer as the upper side, positive electrode tab, positive electrode with the coated surface as the upper surface, 58 mm × 110 mm separator (polypropylene microporous film), negative electrode with the coated surface as the lower surface, negative electrode tab, adhesive layer Was laminated in the order of 90 mm × 150 mm outer package, and three sides were heat-sealed with a width of 15 mm to form a bag. For the remaining one side, 10 mm × 50 mm × 15 μm aluminum foil is taken out from the bag as tabs of the positive electrode and the negative electrode, and LiPF ₆ is added to a solution of ethylene carbonate / diethyl carbonate / dimethyl carbonate = 1/1/1. Was filled with an electrolyte adjusted to 1.5M, and then heat sealed. Heat sealing was performed under the conditions of 160 ° C. × 1 kg / cm 2 × 1 second.

Example 2
In Example 1, an exterior body and a battery were obtained by performing the same operation as in Example 1 except that E-2 was used instead of the acid-modified polyolefin resin aqueous dispersion E-1.

Example 3
In Example 1, an exterior body and a battery were obtained in the same manner as in Example 1 except that the application amount of the anchor layer and the adhesive layer was 0.07 g / m ² .

Example 4
In Example 1, an exterior body and a battery were obtained in the same manner as in Example 1 except that an ethylene-methacrylic acid copolymer (Mitsui / Du Pont Chemical Co., Ltd. Nucrel AN4228C) was used as the sealant resin.

Comparative Example 1
In Example 1, an exterior body was obtained in the same manner as in Example 1 except that E-3 was used instead of the acid-modified polyolefin resin aqueous dispersion E-1.

Comparative Example 2
In Example 1, a polyurethane resin was used as the adhesive layer instead of the acid-modified polyolefin resin. That is, the same operation as in Example 1 was performed using a 10% diluted solution of an aqueous polyurethane resin dispersion (Asahi Denka Co., Adekabon titer HUX380, solid concentration 37% by mass) instead of E-1. An exterior body was obtained.

Comparative Example 3
In Example 1, without forming the anchor layer, the exterior body and the battery were prepared in the same manner as in Example 1 except that the exterior body was obtained by melt-extrusion of LDPE directly onto the aluminum foil surface of the barrier base material. Obtained.

Comparative Example 4
In Example 1, an exterior body and a battery were obtained in the same manner as in Example 1 except that the adhesive layer was not formed.

  Each exterior body obtained in Examples 1 to 4 and Comparative Examples 1 to 4 was subjected to an electrolytic solution resistance, water resistance, and liquid leakage resistance test. The results are shown in Table 2.

In Examples 1-4, all were excellent in electrolyte solution resistance, water resistance, and liquid leakage resistance.
However, each comparative example has the following problems.

  In Comparative Examples 1 and 2, since the resin used as the anchor layer and the adhesive layer was out of the scope of the present invention, the resistance to electrolytic solution and the water resistance were inferior.

  In Comparative Examples 3 and 4, since only one of the anchor layer and the adhesive layer was formed, the leakage resistance was inferior.

Claims (6)

A base material layer, a barrier layer, an anchor layer, a sealant layer, and an adhesive layer are laminated in this order, and the anchor layer and the adhesive layer include an acid-modified polyolefin resin containing a (meth) acrylic acid ester component. The battery outer body. Battery exterior body according to claim 1, wherein the basis weight of the anchor layer and the adhesive layer is in the range of 0.001 to 5 g / m ^2. A battery comprising a power generation element and the battery outer package according to claim 1.   3. The method for producing a battery case according to claim 1, wherein when the anchor layer and the adhesive layer are provided, an aqueous dispersion of an acid-modified polyolefin resin is applied to the barrier layer or sealant layer and the medium is dried. .   An aqueous dispersion is applied to the barrier layer and dried to form an anchor layer, and then the sealant layer is laminated by melt extrusion of the sealant resin in-line, and then the aqueous dispersion is applied to the sealant layer and dried to adhere. The production method according to claim 4, wherein the layer is a layer. When providing the anchor layer and the adhesive layer, the aqueous dispersion of acid-modified polyolefin resin is coated on both sides of the sealant film and dried, and the anchor layer is applied to one side of the sealant film and the adhesive layer is applied to the other side. The manufacturing method of Claim 4 which laminates | stacks the said anchor layer provided in the sealant film with a barrier layer by heat bonding after forming.