JP2001229887A - Packaging material for polymer battery and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material having a good protection property of packaging for a polymer battery and a method of good productivity thereof. SOLUTION: The housing material for the polymer battery is composed of at least the following components; a substrate layer, an adhesive layer, a chemically treated layer, aluminum, a chemically treated layer, the adhesive resin layer and a heat-sealed layer. The adhesive resin layer comprising polyethylene resin denatured with acid and the heat-sealed layer comprising polyethylene resin are co-extruded to give the multi-layered structure. The method of manufacture is composed of the following procedures; both faces of aluminum are chemically treated, after one of both faces chemically treated is dry-laminated with the substrate, the other face of chemically treated aluminum is contacted with the multi-layered structure obtained through the co-extrusion of both the adhesive resin layer and the heat sealed layer, then, heated at the temperature of equal or more than the softening point of the adhesive resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid organic electrolyte (polymer polymer electrolyte) having moisture resistance and content resistance.
The present invention relates to a polymer battery packaging material.

[0002]

2. Description of the Related Art A polymer battery, also called a lithium secondary battery, is a battery having a polymer electrolyte and generating an electric current by the movement of lithium ions, wherein the positive and negative electrode active materials are made of a polymer. Is included.
The structure of the lithium secondary battery is as follows: a positive electrode current collector (aluminum, nickel) / a positive electrode active material layer (a metal positive electrode material such as metal oxide, carbon black, metal sulfide, electrolyte solution, polyacrylonitrile) / an electrolyte layer (propylene) Carbonate-based electrolytes such as carbonate, ethylene carbonate, dimethyl carbonate, and ethylene methyl carbonate; inorganic solid electrolytes composed of lithium salts; gel electrolytes) / Negative electrode active materials (lithium metals, alloys, carbon, electrolytes, and polymers such as polyacrylonitrile) A negative electrode material) / a negative electrode current collector (copper, nickel, stainless steel) and an outer package that wraps them. Applications of polymer batteries include personal computers, mobile terminals (mobile phones, PDAs, etc.), video cameras, electric vehicles, storage batteries for energy storage, robots,
Used for satellites. As the outer package of the polymer battery, a metal can formed by pressing a metal into a cylindrical or rectangular parallelepiped container, or an outermost layer, aluminum, and a laminate formed of a sealant layer are formed into a bag shape. Was used.

[0003]

However, there have been the following problems as the exterior body of the polymer battery. In a metal can, the shape of the battery itself is determined because the outer wall of the container is rigid. Therefore, since the hardware side is designed to match the battery, the size of the hardware using the battery is determined by the battery, and the degree of freedom of the shape is reduced. Therefore, a pouch type in which the laminate is stored in a bag shape to accommodate the polymer battery main body, or an emboss type in which the laminate is press-formed to form a concave portion and the polymer battery main body is accommodated in the concave portion has been developed. The embossed type provides a more compact package as compared to the pouch type. Regardless of the type of the exterior body, the strength such as moisture resistance or puncture resistance, insulation properties, and the like of the polymer battery are indispensable as the exterior body of the polymer battery. The packaging material for a polymer battery is a laminate comprising at least a substrate layer, a barrier layer, and a heat seal layer. Then, it has been confirmed that the adhesive strength between the layers affects the properties required for the outer package of the polymer battery. For example, if the adhesive strength between the barrier layer and the heat seal layer is insufficient, it causes moisture to enter from the outside, and hydrogen fluoride generated by the reaction between the electrolyte and the electrolyte in the components forming the polymer battery The aluminum surface is corroded by the acid, and delamination occurs between the barrier layer and the heat seal layer. Further, when forming the embossed type exterior body, the laminate is press-molded to form a concave portion. In this molding, delamination may occur between the outermost layer and the barrier layer. Therefore, the present inventors applied an acid-modified polypropylene emulsion to the aluminum surface and baked it to form a film, and formed an adhesive resin layer made of acid-modified polyethylene resin and a heat seal layer made of polyethylene resin together. It was confirmed that if the laminate was formed by extrusion, the adhesive strength of the laminate could be improved, but the baking after the emulsion coating of the acid-modified polypropylene was time consuming and the production efficiency was not good. In addition, when a polypropylene resin is used for the heat seal layer, the heat seal portion has poor cold resistance, and is stored at −20 ° C. or less, and when dropped, the heat seal portion is cracked, and the heat seal portion is further broken. Contents leaked in some cases.
An object of the present invention is to provide, as a material used for a polymer battery package, a production method having high productivity as well as protection physical properties of a polymer battery main body.

[0004]

The present invention provides an adhesive resin comprising at least a base material layer, an adhesive layer, a chemical conversion treatment layer, aluminum, a chemical conversion treatment layer, an adhesive resin layer, and a heat seal layer. A polymer battery packaging material formed by a co-extrusion method with a heat seal layer consisting of, wherein the chemical conversion treatment includes a phosphoric acid chromate treatment, and the production method includes performing a chemical conversion treatment on both surfaces of aluminum, After dry laminating the substrate and one surface subjected to the chemical conversion treatment, an acid-modified polyethylene resin and a polyethylene resin are coextruded on the other surface subjected to the chemical conversion treatment to form a laminate, and the laminate is formed. The body is heated by post-heating so that the acid-modified polyethylene resin is at or above its softening point. Further, a polymer battery comprising at least a base material layer, an adhesive layer, aluminum, a chemical conversion treatment layer, an adhesive resin layer, and a heat seal layer, and formed by co-extrusion of an adhesive resin composed of acid-modified polyethylene and a heat seal layer composed of polyethylene. A packaging material, wherein the chemical conversion treatment is a phosphoric acid chromate treatment, and the production method includes subjecting one surface of aluminum to a chemical conversion treatment, and dry laminating the substrate and the surface not subjected to the chemical conversion treatment of the aluminum. After that, the acid-modified polyethylene resin and the polyethylene resin are co-extruded on the other surface subjected to the chemical conversion treatment to form a laminate, and the laminate is post-heated so that the acid-modified polyethylene resin has a softening point or higher. The heating is performed under the following conditions.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention provides a moisture-proof property,
And a packaging material for a polymer battery with good productivity,
The surface of the barrier layer is subjected to a chemical conversion treatment, the base layer is bonded to one side of the barrier layer by dry lamination, and the other side is co-extruded with an acid-modified polyethylene resin and a polyethylene resin to form a laminate, and then The adhesive strength is improved by heating. FIG. 1 is a cross-sectional view illustrating the configuration of a laminate in the packaging material for a polymer battery of the present invention. FIG. 2 is a perspective view illustrating a pouch type exterior body of a polymer battery. FIG. 3 is a perspective view illustrating an embossed type exterior body of a polymer battery. FIG.
(A) perspective view, (b) embossed exterior body body, (c) X ₂
-X ₂ parts cross-sectional view, an enlarged view (d) Y ₁ parts. FIG. 5 is a conceptual diagram illustrating a co-extrusion method for producing a packaging material for a polymer battery. FIG. 6 is a perspective view illustrating a method of mounting an adhesive film in bonding a packaging material for a polymer battery to a tab.

When the packaging material for a polymer battery is, for example, nylon / adhesive layer / aluminum / adhesive layer / polyethylene, and the adhesive layer is formed by a dry lamination method, when the exterior body of the polymer battery is an embossed type, In press molding, delamination that peels off between the aluminum and the base material layer often occurs in the side wall portion, and delamination also occurs in a portion where the polymer battery main body is housed in the outer package and the periphery thereof is heat-sealed. There was an outbreak. In addition, hydrogen fluoride generated by a reaction between an electrolyte, which is a component of the battery, and moisture may attack the inner surface of aluminum and cause delamination.

Therefore, the present inventors have proposed a method for embossing,
At the time of heat sealing, it is a laminate that does not generate delamination, and as a result of earnest research on a packaging material that can be satisfied as an outer package for a polymer battery with content resistance, subjected to chemical conversion treatment on both sides of aluminum, After laminating an acid-modified polyethylene (hereinafter sometimes referred to as PEa) such as an unsaturated carboxylic acid-grafted linear low-density polyethylene and a polyethylene film on the chemical conversion treatment surface on the aluminum content side by a co-extrusion method. The inventors have found that the above problem can be solved by post-heating the obtained laminate, and have completed the present invention.

As shown in FIG. 1, the layer structure of the packaging material for a polymer battery according to the present invention comprises at least a substrate layer 11, an adhesive layer 16, a chemical conversion layer 15 (1), aluminum 12, and a chemical conversion layer 15 (2). ), A laminate comprising an adhesive resin layer 13 and a heat seal layer (polyethylene resin) 14, wherein the adhesive resin layer 13 and the heat seal layer are laminated by a co-extrusion method, and the obtained laminate is described later. After that, the adhesive strength is improved by heating.

According to the present invention, as shown in FIG.
2, a chemical conversion treatment layer 15 is provided on both surfaces, an adhesive resin layer made of an acid-modified polyethylene resin and a heat seal layer made of a polyethylene resin are co-extruded, and the formed laminate is post-heated to form an adhesive resin layer. Is a method of heating to above the softening point.

The packaging material for a polymer battery forms an outer package for packaging the main body of the polymer battery. Depending on the type of the outer package, a pouch type as shown in FIG.
There is an embossed type as shown in FIG. 3 (a), FIG. 3 (b) or FIG. 3 (c). The pouch type includes a bag type such as a three-side seal, a four-side seal, and a pillow type. FIG. 2 illustrates the pouch type as a pillow type. In addition, as the emboss type, a concave portion may be formed on one side as shown in FIG. 3A, or a concave portion may be formed on both surfaces as shown in FIG. It may be housed and heat-sealed on the four sides of the periphery to seal.
There is also a type in which a concave portion is formed on both sides of a folded portion as shown in FIG. 3C, a polymer battery is housed, and three sides are heat-sealed. As shown in FIG. 1, the layer structure of the packaging material for a polymer battery according to the present invention includes at least an outermost layer 11, a chemical conversion layer 15, a barrier layer 12, and a chemical conversion layer 1.
5, a laminate comprising an adhesive resin layer 13 and a heat seal layer 14, wherein the adhesive resin layer 13 and the heat seal layer 14 are laminated by a co-extrusion method. The heat seal layer is made of a polyethylene resin. In the case of an embossed type exterior body, a laminate having excellent moldability is required in order to form a concave portion serving as a storage part for packaging the polymer battery body. Next, the materials constituting each layer of the laminate and the bonding will be described.

In the present invention, the outermost layer 11 is made of a stretched polyester or nylon film. At this time, as the polyester resin, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolymerized polyester, polycarbonate And the like. As nylon, polyamide resin, that is, nylon 6,
Nylon 6,6, a copolymer of Nylon 6 and Nylon 6,6, Nylon 6,10, polymethaxylylene adipamide (MXD6) and the like.

When the outermost layer 11 is used as a polymer battery, the outermost layer 11 is a portion which is in direct contact with a hard disk.
Basically, a resin layer having an insulating property is preferable. In consideration of the existence of pinholes in the film alone and the occurrence of pinholes during processing, the outermost layer needs to have a thickness of 6 μm or more, and the preferred thickness is 12 to 25 μm.

In the present invention, the outermost layer 11 can be laminated in order to improve the pinhole resistance and the insulation when the battery is used as an outer package. When the outermost layer is formed into a laminate, the outermost layer includes at least one resin layer of two or more layers, and each layer has a thickness of 6 μm or more, preferably 1 μm or more.
2 to 25 μm. As an example of laminating the outermost layer,
Although not shown, the following 1) to 7) can be mentioned. 1) Stretched polyethylene terephthalate / stretched nylon 2) Stretched nylon / stretched stretched polyethylene terephthalate Also, mechanical suitability of the packaging material (stability of transportation in packaging machines and processing machines), surface protection (heat resistance, electrolyte resistance) ) When the exterior body for a polymer battery is embossed as a secondary process, the outermost layer is multilayered in order to reduce the frictional resistance between the mold and the outermost layer during embossing. It is preferable to provide a resin layer, an acrylic resin layer, a silicone resin layer, or the like. For example, 3) Fluorine-based resin / stretched polyethylene terephthalate (fluorine-based resin is formed into a film or liquid coating and then dried) 4) Silicone-based resin / stretched polyethylene terephthalate (silicone-based resin is film-like or liquid 5) Fluorine resin / stretched polyethylene terephthalate /
Stretched nylon 6) Silicone resin / Stretched polyethylene terephthalate / Stretched nylon 7) Acrylic resin / Stretched nylon (Acrylic resin is cured by drying after film-like or liquid coating)

The barrier layer 12 is a layer for preventing water vapor from particularly entering the inside of the polymer battery from the outside, and stabilizes the pinholes of the barrier layer alone and the workability (pouching, embossability). And a metal such as aluminum or nickel having a thickness of 15 μm or more to have a pinhole resistance, or an inorganic compound, for example, a film obtained by depositing silicon oxide, alumina, or the like. Aluminum having a thickness of 20 to 80 μm. In order to further improve the occurrence of pinholes and to make the type of the outer package of the polymer battery an embossed type, in order to eliminate the occurrence of cracks and the like in the embossing, the present inventors made use of aluminum used as a barrier layer. The material has an iron content of 0.3-9.
By setting the content to 0% by weight, preferably 0.7 to 2.0% by weight, the aluminum has good ductility and less occurrence of pinholes due to bending as a laminate, compared to aluminum containing no iron. It has been found that the side wall can be easily formed when the embossed type exterior body is molded. The iron content is 0.3% by weight
If less than the above, no effects such as prevention of pinholes and improvement in embossability are observed, and if the iron content of the aluminum exceeds 9.0% by weight, flexibility as aluminum is impaired. As a result, the bag-making properties of the laminate deteriorate.

[0015] Further, the aluminum produced by cold rolling has its flexibility and flexibility under the conditions of annealing (so-called annealing treatment).
Although the strength and hardness of the waist change, the aluminum used in the present invention is harder than the hard treated product without annealing.
Aluminum with a tendency to soften slightly or completely annealed is preferred. The degree of flexibility, waist strength, and hardness of aluminum, that is, the conditions of annealing,
What is necessary is just to select suitably according to workability (pouching, embossing). For example, in order to prevent wrinkles and pinholes during embossing, soft aluminum annealed according to the degree of forming can be used.

The inventors of the present invention have conducted intensive studies on the object of the present invention, and as a result, have found that the barrier layer 12
By subjecting the aluminum front and back surfaces to a chemical conversion treatment, a laminate that was satisfactory as the packaging material could be obtained. The chemical conversion treatment is specifically to prevent delamination between aluminum and the substrate layer during embossing by forming an acid-resistant film such as a phosphate, a chromate, a fluoride, and a triazine thiol compound. And the hydrogen fluoride generated by the reaction between the electrolyte of the polymer battery and water, to prevent the dissolution and corrosion of the aluminum surface, especially the dissolution and corrosion of the aluminum oxide present on the aluminum surface, and Improves adhesion (wetability), prevents delamination between the base layer and aluminum during embossing and heat sealing, and prevents delamination on the inner surface of aluminum by hydrogen fluoride generated by the reaction between electrolyte and moisture The effect was obtained. As a result of studying the effect of chemical conversion treatment on the aluminum surface using various substances, among the above-mentioned acid-resistant film-forming substances, phenolic resin, chromium fluoride (3) compound, and phosphoric acid The phosphoric acid chromate treatment using the treated product was good.

In the case where the outer casing of the polymer battery is a pouch type, the chemical conversion treatment may be performed only on one side of the innermost layer of aluminum. When the exterior body of the polymer battery is an embossed type, delamination between aluminum and the base layer during embossing can be prevented by performing a chemical conversion treatment on both surfaces of aluminum. A laminate having a chemical conversion treatment on both surfaces of aluminum may be used for the pouch type.

In a laminate obtained by co-extruding an acid-modified polyethylene resin and a polyethylene resin on the chemical conversion treated surface, the adhesiveness of the extruded acid-modified polyethylene resin to the chemical conversion treated surface is poor. On the chemical conversion treated surface, an emulsion of acid-modified polyethylene is applied by a roll coating method or the like, dried, baked at a temperature of 170 to 200 ° C., and then co-extruded to form a laminate. Although the bonding strength is improved, the processing speed of the baking is extremely slow, and the productivity is poor.

The inventors of the present invention have conducted intensive studies on a laminating method exhibiting stable adhesive strength without applying or baking an acid-modified polyethylene, and as a result, have found that one side of the base layer and one side of the barrier layer chemically converted on both sides can be obtained. Is dry-laminated, and an acid-modified polyethylene resin and polyethylene resin are coextruded on the other surface of the barrier layer to form a laminate, and the laminate is heated to a condition where the acid-modified polyethylene resin is at or above its softening point. As a result, a laminate having a predetermined adhesive strength could be obtained. As a specific method of the heating, there are methods such as a hot roll contact type, a hot air type, near or far infrared rays, but any heating method may be used in the present invention, and as described above, the adhesive resin is softened. What is necessary is just to be able to heat above the point temperature.

As another method, the adhesive strength can also be increased by heating the surface temperature of the aluminum on the heat seal layer side to the softening point of the acid-modified polyethylene resin during the co-extrusion lamination. A stable laminate was obtained. The acid-modified PE has (1) a density of 0.91 g / cm ³ or more, a bigat softening point of 80 ° C. or more,
Linear low density polyethylene with melting point of 110 ° C or higher (LLDP
E), (2) a medium density polyethylene (MDPE) having a density of 0.92 g / cm ³ or more, a bigat softening point of 80 ° C. or more, and a melting point of 115 ° C. or more, and (3) a density of 0.94 g / cm ³ or more, a bigat softening point of 90. It is a simple substance or a blend obtained by acid-modified polymerization using an unsaturated carboxylic acid with high-density polyethylene (HDPE) having a melting point of 125 ° C. or higher and a melting point of 125 ° C. or higher. The acid-modified PE has a density of 900.
kg / m ³ or less low-crystalline ethylene butene copolymer, low-crystalline propylene butene copolymer, or amorphous ethylene-propylene copolymer, amorphous propylene-ethylene copolymer, An ethylene-butene-propylene copolymer or the like may be added in an amount of 5% or more to impart flexibility, improve bending resistance, and prevent cracking during molding.

As a laminate of the polymer battery packaging material of the present invention, in addition to the above-mentioned substrate layer, barrier layer, adhesive resin layer, heat seal layer (PE), an intermediate layer between the barrier layer and the adhesive resin layer. A layer may be provided. The intermediate layer may be laminated for improving strength as a packaging material for a polymer battery, improving and stabilizing barrier properties, and the like.

Each of the above-mentioned layers in the laminate of the present invention includes:
Appropriate surface activation such as corona treatment, blast treatment, oxidation treatment, ozone treatment, etc. for the purpose of improving and stabilizing the suitability for film forming, lamination processing, and final processing of secondary products (pouching, embossing) as appropriate. Processing may be performed.

For the heat seal layer of the laminate in the packaging material for a polymer battery of the present invention, polyethylene is preferably used. The use of polyethylene for the heat seal layer means that the heat sealability between polyethylene is good,
Has the required protective physical properties as a heat seal layer for polymer battery packaging materials such as moisture proof and heat resistance, and also has good laminating processability, good embossing processability, etc.
It is a desirable material. The polyethylene used for the heat seal layer includes (1) a density of 0.91 g / cm.
^A linear low-density polyethylene (LLDPE) having a softening point of 80 ° C. or higher and a melting point of 110 ° C. or higher; (2) a density of 0.92 g / cm ³ or higher;
Medium density polyethylene (MDPE) with a melting point of 115 ° C or higher,
(3) Density 0.94 g / cm ³ or more, bigat softening point 90
A single layer or a multilayer of a single substance or a blend of high density polyethylene (HDPE) having a melting point of 125 ° C. or higher and a melting point of 125 ° C. or higher is used.

The polyethylene has a density of 90.
0 kg / m ³ or less low-crystalline ethylene butene copolymer, low-crystalline propylene butene copolymer, or amorphous ethylene-propylene copolymer, amorphous propylene-ethylene copolymer, An ethylene-butene-propylene copolymer or the like may be added in an amount of 5% or more to impart flexibility, improve bending resistance, and prevent cracking during molding. Or, by adding polypropylene,
Slipperiness can be imparted in the process of forming or pouch-making.

However, since polyethylene does not have a heat-sealing property with respect to a metal, the heat-sealing of the tab portion in the polymer battery requires heat treatment as shown in FIGS. 6 (a), 6 (b) and 6 (b).
As shown in (c), by interposing an adhesive film having heat sealing property for both metal and PE between the tab and the heat sealing layer of the laminate, the sealing property at the tab portion is also improved. Be certain. The adhesive film is shown in FIG.
(D) As shown in FIGS. 6 (e) and 6 (f), the tab may be wound around a predetermined position. As the adhesive film, the unsaturated carboxylic graft polyolefin,
A film made of metal cross-linked polyethylene or a copolymer of ethylene or propylene and acrylic acid or methacrylic acid can be used.

It is desirable that the base material and the chemical conversion-treated surface of the barrier layer in the packaging material for a polymer battery of the present invention be bonded by a dry lamination method. As the adhesive used for dry lamination of the substrate and the phosphate chromate-treated surface of aluminum, polyester, polyethyleneimine, polyether, cyanoacrylate, urethane, organic titanium, polyether urethane, Epoxy, polyester urethane, imide,
Various isocyanate-based, polyolefin-based, and silicone-based adhesives can be used.

[0027]

EXAMPLES The packaging material for a polymer battery of the present invention is described below.
Examples will be described more specifically. Chemical conversion treatment
Displacement may also be caused by phenol resin, chromium fluoride
(Ii) Roll coating of aqueous solution consisting of compound and phosphoric acid
Condition by which the coating temperature is 180 ℃ or higher
Baked in Chromium coating amount is 10mg / m^Two
(Dry weight). Example 1, Comparative Example 1, Comparative Example 3, and
Comparative Example 5 is a pouch type exterior body.
0mm width and length, 80mm pillow type pouch
The bag was made, the polymer battery main body was housed, and hermetically sealed.
In addition, Example 2, Comparative Example 2, Comparative Example 4, and Comparative Example 6
Embossed type exterior body, all single-sided embossed tie
And the shape of the concave part (cavity) of the mold is 30 mm
× 50mm, 3.5mm depth, press molding
The sex was evaluated. In each case, the tab of the polymer battery
In the seal part, a 20 μm thick adhesive film
From unsaturated carboxylic acid grafted linear low density polyethylene
Film around the seal of the tab
I did. [Example 1] (Pouch type) A chemical conversion treatment was performed on both surfaces of aluminum 20 μm.
Stretched polyester film (thickness 16
μm) by dry lamination, and then
On the other side of the chemically treated aluminum, a softening point of 90 ° C.
An acid-modified polyethylene having a melting point of 122 ° C. is bonded to an adhesive resin (thickness 2).
0 μm), softening point 115 ° C., melting point 123 ° C., thickness 30
μ linear low density polyethylene (LLDPE, thickness 30μ)
m) is co-extruded to form a laminate, and the resulting laminate is
Heat the test so that the surface temperature of the luminium becomes 110 ° C
Body Example 1 was obtained. [Example 2] (Emboss type) A chemical conversion treatment was performed on both surfaces of aluminum 40 µm.
Dry laminating 25μm nylon on one side
And then soften the other surface
Acid-modified polyethylene (high temperature 120 ° C, melting point 130 ° C)
Density polyethylene: HDPE, thickness 20μm) and HD
PE resin (softening point 125 ° C, melting point 132 ° C, thickness 30μ
m) and co-extruded to form a laminate, and the resulting laminate is
Heat the aluminum surface temperature to 140 ° C
Sample Example 2 was obtained. [Comparative Example 1] (Pouch type) A chemical conversion treatment was performed on both surfaces of aluminum 20 μm.
Stretched polyester film 12 μm on one side
Lamination by dry lamination method, then chemical conversion treatment
On the other side of the treated aluminum, a softening point of 90 ° C. and a melting point of 12
2 ° C acid-modified polyethylene (linear low density polyethylene,
Softening point 115 ° C, melting point 123 ° C, LLDPE, thickness 20
μm), softening point 115 ° C., melting point 123 ° C., thickness 30 μm
Linear low density polyethylene (LLDPE, thickness 30μ)
m) was co-extruded to form a laminate to obtain Sample Comparative Example 1.
Was. [Comparative Example 2] (Embossed type) A chemical conversion treatment was performed on both surfaces of 40 μm aluminum.
Dry laminating 25μm nylon on one side
And then soften the other surface
Acid-modified polyethylene (high temperature 120 ° C, melting point 130 ° C)
Density polyethylene: HDPE) (thickness 20 μm) and H
DPE resin (softening point 125 ° C, melting point 132 ° C, thickness 30
μm) was co-extruded to obtain Sample Comparative Example 2. [Comparative Example 3] (pouch type) Stretched polyester film on one surface of aluminum 20 µm
The film is laminated by dry lamination and then
On the other side of the aluminum, acid-modified polyether with a softening point of 90 ° C
Tylene (linear low density polyethylene: LLDPE), melting point
115 ° C. (thickness 20 μm) and LLDPE resin (softening point 1
15 ° C, melting point 123 ° C, thickness 30μm)
A laminate is formed, and the obtained laminate is placed on an aluminum surface.
Heated to 130 ° C. to obtain Sample Comparative Example 3
Was. [Comparative Example 4] (Embossed type) Nylon 25 µm on one side of aluminum 40 µm
Lamination by dry lamination, then aluminum
On the other side of the alloy, a softening point of 120 ° C and a melting point of 130 ° C.
Polyethylene (high-density polyethylene: HDPE),
HDPE resin (softening point 125 ° C, melting point 132 ° C, thickness 3
0 μm) to form a laminate, and the resulting laminate
Heat the body so that the surface temperature of aluminum becomes 150 ° C
Thus, Sample Comparative Example 4 was obtained. [Comparative Example 5] (Pouch type) Stretched polyester film on one side of aluminum 20 µm
The film is laminated by dry lamination and then
On the other side of the aluminum, acid-modified poly with a softening point of 120 ° C
Propylene (20 μm thick) and polypropylene resin (soft
Co-extrusion at 140 ° C, melting point 157 ° C, thickness 30μm)
To form a laminate, and the resulting laminate is
Specimen Comparative Example 5 by heating so that the surface temperature of the sample became 150 ° C.
I got [Comparative Example 6] (Embossed type) Stretched polyester film on one side of aluminum 40 µm
The film is laminated by dry lamination and then
On the other side of the aluminum, acid-modified poly with a softening point of 120 ° C
Propylene is mixed with adhesive resin (thickness 20μm) and polypropylene
Ren resin (softening point 140 ° C, melting point 157 ° C, thickness 30μ)
m) and co-extruded to form a laminate, and the resulting laminate
Is heated so that the surface temperature of aluminum becomes 150 ° C.
Thus, Sample Comparative Example 6 was obtained. <Embossing and packaging> Example 1 of each sample obtained, ratio
Comparative Example 1, Comparative Example 3 and Comparative Example 5 were made as pouches.
Example 2, Comparative Example 2, Comparative Example 4, and Comparative Example 6
Molding and packing the polymer battery body
Was evaluated. <Evaluation method> 1) Delamination during molding Immediately after molding, delamination between aluminum and substrate layer
Was checked. 2) Content resistance As a storage condition, each sample was subjected to a constant temperature of 60 ° C. and 90% RH.
After storage in the tank for 7 days, the aluminum and PE dela
The presence or absence of the termination was confirmed. 3) Delamination during heat sealing Delamination between aluminum and innermost resin layer immediately after heat sealing
The presence or absence of the termination was confirmed. 4) Cold resistance Filled with a weight of 20 g and sealed by heat sealing
The sample is placed in a -40 ° C environment from a height of 50 cm.
And check for cracks in the heat seal area.
Was. <Results> In both Examples 1 and 2, when embossing,
No delamination at heat sealing
Due to delamination and -40 ° C environment
No cracks in the heat-sealed part when falling
Was. Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 5
In addition, delamination during heat sealing is acceptable.
It did not fit. Data during embossing molding in Comparative Example 2
There was no lamination. However, Comparative Example 1, Comparative Example
2, Delamine on the contents side in both Comparative Examples 3 and 5
Solution was observed in all of the 100 samples. Comparative example
4 and Comparative Example 6 each had 1 at the time of heat sealing.
Delamination occurred in 40 or 46 samples out of 00 samples
Was. In addition, delamination due to content resistance is
It was found in all of the 100 samples. Comparative Examples 5 and 6
Is a drop from a height of 50 cm at -40 ° C.
Cracks in the seal area are 20 out of 100 samples each
I was born.

[0028]

The chemical conversion treatment applied to both surfaces of aluminum in the packaging material for polymer batteries of the present invention prevents the occurrence of delamination between the base material layer and aluminum during embossing and heat sealing. In addition, by preventing corrosion of the aluminum surface due to hydrogen fluoride generated by the reaction between the electrolyte of the polymer battery and moisture, a significant effect of preventing delamination of aluminum with the content side layer can be prevented. Is shown.
In addition, since acid-modified polyethylene resin and polyethylene resin can be laminated by a co-extrusion method, productivity is good,
The post-heat treatment of the laminate can provide the adhesive strength required as a packaging material for a polymer battery, and thus can be used as an outer package of a polymer battery.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating the configuration of a laminate in a packaging material for a polymer battery of the present invention.

FIG. 2 is a perspective view illustrating a pouch type exterior body of a polymer battery.

FIG. 3 is a perspective view illustrating an embossed type exterior body of a polymer battery.

FIG. 4 illustrates molding in an emboss type.
(A) a perspective view, (b) an embossed exterior body body,
(C) X ₂ -X ₂ parts cross-sectional view, an enlarged view (d) Y ₁ parts.

FIG. 5 is a conceptual diagram illustrating a co-extrusion method for producing a packaging material for a polymer battery.

FIG. 6 is a perspective view illustrating a method of mounting an adhesive film in bonding a packaging material for a polymer battery and a tab.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polymer battery 2 Polymer battery main body 3 Cell (power storage part) 4 Tab (electrode) 5 Outer body 6 Adhesive film (tab part) 7 Concave part 8 Side wall part 9 Seal part 10 Laminated body (packaging material for polymer batteries) 11 Base material layer 12 Aluminum (Barrier Layer) 13 Acid-Modified Polyethylene Layer 14 Heat Seal Layer (Polyethylene) 15 Chemical Conversion Layer 16 Adhesive Layer 20 Press Forming Section 21 Male Type 22 Female Type 23 Cavity 30 Sandwich Laminating Device 31 Extruder 32 Die 33 Molten Resin Film 34 chill roll 35 pressure roll 36 laminate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Kazuki Yamada 1-1-1, Ichigaya Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Hiroshi Miyama 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo No. 1 Dai Nippon Printing Co., Ltd. F term (reference) 4J040 DA021 DA151 DA161 JB01 NA06 NA19 5H011 AA02 AA09 BB04 CC02 CC10 DD09 DD12

Claims (6)

[Claims] (1) at least a substrate layer, an adhesive layer, a chemical conversion treatment layer,
A packaging material for polymer batteries, comprising aluminum, a chemical conversion layer, an adhesive resin layer, and a heat seal layer, wherein an adhesive resin made of acid-modified polyethylene and a heat seal layer made of polyethylene are formed by a co-extrusion method. 2. The packaging material for a polymer battery according to claim 1, wherein the chemical conversion treatment is a phosphoric acid chromate treatment. 3. A chemical conversion treatment is performed on both surfaces of aluminum, and a base material and one surface subjected to the chemical conversion treatment are dry-laminated, and then the other surface subjected to the chemical conversion treatment is subjected to acid-modified polyethylene resin and polyethylene resin. A co-extrusion to form a laminate, and heating the laminate by post-heating so that the acid-modified polyethylene resin has a softening point or higher. 4. An adhesive resin comprising at least a base material layer, an adhesive layer, aluminum, a chemical conversion layer, an adhesive resin layer, and a heat seal layer, wherein an adhesive resin comprising acid-modified polyethylene and a heat seal layer comprising polyethylene are formed by coextrusion. A packaging material for a polymer battery, comprising: 5. The packaging material for a polymer battery according to claim 4, wherein the chemical conversion treatment is a phosphoric acid chromate treatment. 6. A chemical conversion treatment on one side of aluminum, a dry lamination of a substrate and a surface of the aluminum not subjected to the chemical conversion treatment, and an acid-modified polyethylene resin and a polyethylene resin on the other surface of the chemical conversion treatment. A co-extrusion to form a laminate, and heating the laminate by post-heating so that the acid-modified polyethylene resin has a softening point or higher.