JP4090765B2 - Battery packaging materials - Google Patents

Description

実施例１〜実施例４は、成形深さ、パンチ押し込み量、内面耐電解液ともに良好であったが、特に、実施例４が優れていた。比較例１、比較例２は抜き適性が悪く、比較例３は成形性、抜き適性ともに劣り、比較例４は成形性に劣る。比較例５は、成形性、抜き適性は良好であるが、デラミが発生した。
【００２７】
【発明の効果】
本発明の電池用包装材料の少なくともシーラント層を、メタロセン系の線状低密度ポリエチレンとし、不飽和カルボン酸でグラフト変性したポリエチレンを接着樹脂として共押出しラミネートすることによって、エンボス加工適性を損なうことなく、外装体形成工程におけるダイセット抜き加工適性を向上させることができた。
【図面の簡単な説明】
【図１】本発明の電池用包装材料を説明する図で、（ａ）層構成を示した断面図、（ｂ）別の層構成を示した断面図である。
【図２】電池の外装体を形成する際の抜きの実施例について説明する図で、（ａ）電池の斜視図、（ｂ）電池本体と電池本体を挿入する前の外装体の斜視図、（ｃ）外装体の抜き形状を示す上面図である。
【図３】電池のパウチタイプの外装体を説明する斜視図である。
【図４】電池のエンボスタイプの外装体を説明する斜視図である。
【図５】エンボスタイプにおける成形を説明する、（ａ）斜視図、（ｂ）エンボス成形された外装体本体、（ｃ）Ｘ₁−Ｘ₁部断面図、（ｄ）Ｙ₁部拡大図である。
【図６】シーラント部の共押出しラミネートの実施例を示す概念図である。
【符号の説明】
Ｔ 抜き線
ｍ 折り返し線
１ 電池
２ 電池本体
３ セル（蓄電部）
４ リード線（電極）
５ 外装体
５Ｖ トレイ部
５Ｆ 蓋部
６ リード線用フィルム
７ 凹部
８ 側壁部
９ シール部
１０ 積層体（電池用包装材料）
１１ 基材層
１２ バリア層
１３ 接着樹脂層
１４ シーラント層
１５ 化成処理層
１６ 基材層とバリア層とのドライラミネート層
２０ プレス成形部
２１ オス型
２２ メス型
２３ キャビティ
３０ 共押出しラミネーター
３１ａ 接着樹脂の押出機
３１ｂ シーラント樹脂の押出機
３２ ダイ
３３ シーラント部の溶融樹脂膜
３４ チルロール
３５ バックアップロール
３６ 中間積層体
３７ 積層体巻取[0001]
BACKGROUND OF THE INVENTION
It is a packaging material used for exterior bodies such as batteries, fuel cells, capacitors, capacitors, etc. that have moisture resistance and content resistance and that have liquid or solid organic electrolytes (polymer polymer electrolytes). The present invention relates to a battery packaging material having a material.
[0002]
[Prior art]
The battery in the present invention includes a device including an element that converts chemical energy into electric energy, for example, a lithium ion battery, a lithium polymer battery, a fuel cell, or a dielectric such as a liquid, a solid ceramic, or an organic substance. Including electrolytic capacitors such as liquid capacitors, solid capacitors, double layer capacitors.
Applications of the battery include personal computers, portable terminal devices (cell phones, PDAs, etc.), video cameras, electric vehicles, energy storage batteries, robots, satellites, and the like.
As the battery exterior body, a metal can obtained by pressing a metal into a cylindrical or rectangular parallelepiped container, or a laminate made of a composite film obtained by laminating a plastic film, a metal foil or the like into a bag shape. (Hereinafter referred to as an exterior body) was used.
There were the following problems as a battery outer package. In a metal can, since the outer wall of the container is rigid, the shape of the battery itself is determined. 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 in shape is reduced.
Therefore, it exists in the tendency to use the said bag-shaped exterior body. The material structure of the exterior body is at least a base material layer, a barrier layer, from the necessary physical properties, workability, economy, etc. as a battery.
It consists of an adhesive layer that adheres the sealant layer and each of the above layers, and an intermediate layer may be provided as necessary.
Form a pouch from the battery stack with the above configuration, or press-mold at least one side to emboss the battery housing to store the battery body, cover it with a non-molded lid, and heat the necessary peripheral part A battery is formed by sealing with a seal.
[0003]
[Problems to be solved by the invention]
In the battery packaging material, the water vapor barrier property is more excellent when the sealant film is laminated by extrusion molding than when the sealant film is laminated by dry lamination. This is because in dry lamination, the adhesive layer becomes a moisture permeable layer.
However, in the formation of the exterior body by the laminated body, depending on the type of the exterior body, it may be punched with a die set in the manufacturing process, and the sandwich laminate method may not completely come off and may generate burrs. In some cases, an uncut portion is left and separation from the uncut portion cannot be performed, thereby impairing productivity.
An object of the present invention is a battery packaging having a structure capable of maintaining the performance of a battery over a long period of time, and further having stable processability in an outer body manufacturing process, that is, excellent embossing suitability and punching suitability. Is to provide materials.
[0004]
[Means for Solving the Problems]
The above problems can be solved by the following present invention. That is, according to the first aspect of the present invention, in the packaging of the battery in which the battery body is inserted and the peripheral edge portion is sealed by heat sealing, the packaging material forming the exterior body is at least a base material layer, an adhesive layer, a barrier layer, a chemical conversion material. A laminate comprising a treatment layer, an adhesive resin layer, and a sealant layer, wherein the adhesive resin layer and the sealant layer are formed by coextrusion , and the sealant layer is a metallocene linear low-density polyethylene resin. It consists of the battery packaging material characterized. According to the second aspect of the present invention, in the packaging of the battery in which the battery body is inserted and the peripheral portion is sealed by heat sealing, the packaging material forming the outer package is at least a base material layer, an adhesive layer, a barrier layer, and a chemical conversion treatment layer. A laminate composed of an adhesive resin layer and a sealant layer , wherein the adhesive resin layer and the sealant layer are formed by coextrusion , and the adhesive resin layer is a polyethylene resin graft-polymerized with an unsaturated carboxylic acid, The sealant layer is made of a battery packaging material, which is a metallocene linear low density polyethylene resin . According to a third aspect of the present invention, in the packaging of the battery in which the battery body is inserted and the peripheral edge is sealed by heat sealing, the packaging material forming the exterior body is at least a base material layer, an adhesive layer, a barrier layer, and a chemical conversion treatment layer. A laminate composed of an adhesive resin layer and a sealant layer , wherein the adhesive resin layer and the sealant layer are formed by coextrusion , the adhesive resin layer is acid-modified polyethylene, and the sealant layer is a metallocene wire. It is a battery packaging material characterized by being a low-density polyethylene resin . The invention described in claim 4 is characterized in that the sealant layer according to any one of claims 1 to 3 is a metallocene linear low density polyethylene resin to which low density polyethylene is added in an amount of 10 wt% to 50 wt%. To do.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The battery packaging material of the present invention comprises at least a base layer, an adhesive layer, a barrier layer, a chemical conversion treatment layer, an adhesive resin layer, and a sealant layer. It has the ability to maintain the performance of the battery for a long time by coextruding and laminating as a low-density linear polyethylene and graft-modified polyethylene with an unsaturated carboxylic acid as an adhesive resin. It is a battery packaging material that has both embossing suitability and die set punching suitability.
[0006]
1A and 1B are diagrams for explaining a battery packaging material according to the present invention, in which FIG. 1A is a cross-sectional view showing a layer structure, and FIG. 1B is a cross-sectional view showing another layer structure. FIGS. 2A and 2B are diagrams for explaining an embodiment in which a battery outer body is formed, in which FIG. 2A is a perspective view of the battery, and FIG. 2B is a perspective view of the outer body before inserting the battery main body and the battery main body. (C) It is a top view which shows the extraction shape of an exterior body. FIG. 3 is a perspective view for explaining a pouch-type exterior body of a battery. FIG.
It is a perspective view explaining the embossed type exterior body of a battery. Figure 5 illustrates the molding in embossed type, (a) a perspective view, (b) embossing the molded outer body, (c) X ₁ -X ₁ part cross-sectional view, with (d) Y ₁ part enlarged view is there. FIG. 6 is a conceptual diagram showing an example of co-extrusion lamination of a sealant part.
[0007]
As a result of diligent research on the materials that are excellent in long-term storage stability of the battery and that are suitable for processing, particularly those that do not cause the above-mentioned defective pulling, as shown in FIG. 1A or FIG. The sealant layer 14 of the packaging material is made into a linear low density polyethylene polymerized using at least a metallocene catalyst (hereinafter referred to as a metallocene linear low density polyethylene), and laminated together with the adhesive resin layer on the barrier layer by coextrusion laminating. As a result, the inventors have found that the occurrence of the above-mentioned punching failure can be prevented and exhibit good embossing suitability, thereby completing the present invention.
[0008]
The battery packaging material forms an exterior body for packaging a main body of a lithium ion battery or the like. Depending on the form of the exterior body, a pouch type as shown in FIG. 3 and FIGS. There is an embossed type as shown in FIG. The pouch type includes three-side seals, four-side seals, and pillow types such as a pillow type. FIG. 3 illustrates a pillow type.
As shown in FIGS. 4A and 4D, the embossed type may be formed with a recess 7 on one side, or as shown in FIG. And may be sealed by heat-sealing the four sides of the periphery. There is also a type in which a concave portion is formed on both sides with a folding portion as shown in FIG. 4 (c), the battery is accommodated, and three sides are heat-sealed.
[0009]
When the battery packaging material is an embossed type, as shown in FIGS. 5 (a) to 5 (d), the laminated packaging material 10 is press-molded to form the recess 7.
[0010]
The battery packaging material is, for example, an embossed type as shown in FIG. 2A, and is made of nylon / adhesive layer / aluminum / adhesive resin layer / sealant layer, and the sealant layer is made of a polyethylene resin layer. When the battery exterior body is processed using the material, for example, an embossed type exterior body as shown in FIG. 2 (b), in which the tray portion 5V and the lid portion 5F are integrated with each other via the folding line m. As a punching shape as the processing step, a shape T as shown in FIG. 2C is obtained, which is a punching step by a die set type punching die.
Regarding die-cutting with the die set, burrs and uncut parts occur when the co-extrusion of the adhesive resin and the sealant layer is laminated rather than the method of sandwich lamination of the pre-formed sealant film with the adhesive resin. It is difficult and effective. On the other hand, co-extrusion is slightly disadvantageous with respect to embossing suitability. This is because the polyethylene resin forming the sealant layer 14 is changed from a conventional low density polyethylene or linear low density polyethylene to a metallocene linear low. It can be improved by replacing with density polyethylene. Furthermore, it was confirmed that the drawability was further improved while maintaining the embossing suitability by blending 10 wt% or more of low density polyethylene with the metallocene linear low density polyethylene resin as the sealant layer.
[0011]
For example, as shown in FIG. 6, the method for producing the battery packaging material of the present invention is the other surface of the barrier layer of the intermediate laminate 36 in which the base material layer and the barrier layer are laminated using a method such as dry lamination. And an adhesive resin and a metallocene linear low-density polyethylene to be a sealant layer are laminated by a co-extrusion laminating method. In addition, at least the surface of the sealant side of the barrier layer is preliminarily subjected to chemical conversion treatment, but the surface of the base material layer side is also subjected to chemical conversion treatment at the time of emboss molding or heat sealing. This is desirable because it has an effect of preventing delamination between the substrate and the barrier layer.
Adhesive resin and metallocene-based linear low density polyethylene resin were heated and melted in extruders 31a and 32b, respectively, and introduced into the die. The laminate is wound on the surface of the barrier layer by pressure cooling with an extrusion cooling roll and a pressure-bonding roll, and wound up as a laminate winding 37.
It is desirable to use polyethylene graft-modified with unsaturated carboxylic acid as the adhesive resin.
[0012]
In order to further increase the laminate strength between the barrier layer and the adhesive resin layer, it is desirable to laminate by heating the laminate surface of the barrier layer to a temperature equal to or higher than the softening point of the adhesive resin during the coextrusion lamination. . As another method for further increasing the laminate strength, the laminated laminate winding may be post-heated so that the winding temperature is equal to or higher than the softening point of the adhesive resin.
[0013]
The surface of the inner surface of the barrier layer was eroded and delaminated by hydrogen fluoride generated by the reaction between the electrolyte, which is a component of the battery, and moisture. The lamination method and the laminated surface of the barrier layer were adhered. Stable adhesive strength was exhibited by laminating the resin as it was heated above the softening point temperature of the resin. As a specific method of heating in the laminating method, there are methods such as a hot roll contact method, a hot air method, a near or far infrared ray, and any heating method may be used in the present invention. What is necessary is just to be able to heat more than the softening point temperature.
Moreover, even if the laminated body obtained by laminating is post-heated so that the adhesive resin has a temperature higher than its softening point, the adhesive strength is stabilized. Any heating method may be used in the present invention.
[0014]
The battery packaging material of the present invention has good moldability even in the embossing process, and is a laminated body that does not generate burrs or remain unplugged in the punching process. It is a packaging material that is satisfactory as an exterior body.
[0015]
In the battery packaging material of the present invention, for each of the layers in the laminate forming the outer package, film forming properties, lamination processing, final product secondary processing (pouching, embossing) suitability are improved and stabilized as appropriate. For this purpose, surface activation treatment such as corona treatment, blast treatment, oxidation treatment, and ozone treatment may be performed.
[0016]
Next, each layer which comprises the battery packaging material of this invention is demonstrated.
As shown in FIG. 1A, the battery packaging material of the present invention includes at least a base material layer 11, an adhesive layer 16, a barrier layer 12, a chemical conversion treatment layer 15, an adhesive resin layer 13, and a sealant layer 14. When the exterior body to be described later is an embossed type, as shown in FIG. 1 (b), the laminate is a base material layer 11, an adhesive layer 16, a chemical conversion treatment layer 15 (1), The barrier layer 12, the chemical conversion treatment layer 15 (2), the adhesive resin layer 13, and the sealant layer 14 are desirable.
The base material layer 11 in the outer package is made of stretched polyester or nylon film. At this time, examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolymer polyester, polycarbonate, and the like. Can be mentioned. Examples of nylon include polyamide resin, that is, nylon 6, nylon 6,6, a copolymer of nylon 6 and nylon 6,6, nylon 6,10, polymetaxylylene adipamide (MXD6), and the like.
When the base material layer 11 is used as a battery, the base material layer 11 is a part that is in direct contact with the hardware. Considering the existence of pinholes in a single film and the generation of pinholes during processing, the base material layer needs to have a thickness of 6 μm or more, and a preferred thickness is 12 to 30 μm.
[0017]
The base material layer 11 can also be laminated in order to improve pinhole resistance and insulation when used as a battery outer package.
When the base material layer is laminated, the base material layer includes at least one resin layer of two or more layers, and the thickness of each layer is 6 μm or more, preferably 12 to 30 μm. Examples of laminating the base material layer include the following 1) to 8).
1) Stretched polyethylene terephthalate / stretched nylon 2) Stretched nylon / stretched stretched polyethylene terephthalate In addition, packaging materials have mechanical suitability (stability of transport in packaging machines and processing machines), surface protection (heat resistance, electrolyte resistance) ) When the battery exterior body is made an embossed type as a secondary processing, the base material layer is protected when the embossing is applied for the purpose of reducing the frictional resistance between the mold and the base material layer during embossing. In order to achieve this, the base material layer may be multilayered, and a fluororesin layer, an acrylic resin layer, a silicone resin layer, a polyester resin layer, or a resin layer made of a blend thereof may be provided on the surface of the base material layer. preferable. For example,
3) Fluorine resin / stretched polyethylene terephthalate (Fluorine resin is a film or formed by drying after liquid coating)
4) Silicone resin / stretched polyethylene terephthalate (silicone resin is a film or formed by drying after liquid coating)
5) Fluorine resin / stretched polyethylene terephthalate / stretched nylon 6) Silicone resin / stretched polyethylene terephthalate / stretched nylon 7) Acrylic resin / stretched nylon
8) Acrylic resin + polysiloxane graft acrylic resin / stretched nylon (acrylic resin is film-like or cured by drying after liquid coating)
[0018]
The barrier layer 12 is a layer for preventing water vapor from entering the inside of the battery from the outside, stabilizing the pinhole and processability (pouching, embossing formability) of the barrier layer alone, and being resistant to resistance. In order to have a pinhole, a metal such as aluminum or nickel having a thickness of 15 μm or more, or a film on which an inorganic compound such as silicon oxide or alumina is deposited may be used. The aluminum is 80 μm.
In order to further improve the generation of pinholes and to make the battery exterior body type an embossed type, in order to prevent the occurrence of cracks in the embossing molding, the present inventors have made a material for aluminum used as a barrier layer. However, when the iron content is 0.3 to 9.0% by weight, preferably 0.7 to 2.0% by weight, the extensibility of aluminum is better than that of aluminum not containing iron. The present inventors have found that the occurrence of pinholes due to bending is reduced as a laminate, and the side wall can be easily formed when the embossed type exterior body is formed. When the iron content is less than 0.3% by weight, effects such as prevention of pinholes and improvement of embossing formability are not observed, and the iron content of the aluminum exceeds 9.0% by weight. In such a case, the flexibility as aluminum is hindered, and the bag-making property is deteriorated as a laminate.
[0019]
In addition, aluminum produced by cold rolling changes its flexibility, waist strength and hardness under annealing (so-called annealing treatment) conditions, but the aluminum used in the present invention is harder than the non-annealed hard-treated product. Aluminum that tends to be soft, with some or complete annealing, is preferred.
The degree of flexibility, waist strength and hardness of aluminum, that is, the conditions for annealing, may be appropriately selected in accordance with processability (pouching, embossing). For example, in order to prevent wrinkles and pinholes during embossing, it is desirable to use soft aluminum annealed according to the degree of forming.
[0020]
By subjecting the front and back surfaces of aluminum, which is the barrier layer 12 of the battery packaging material, to chemical conversion treatment, a laminate having a laminate strength that is satisfactory as the packaging material can be obtained. Specifically, the chemical conversion treatment is to form an acid-resistant film such as phosphate, chromate, fluoride, triazine thiol compound, etc. Among the acid-resistant film-forming substances, phenol resin, chromium fluoride (3) Phosphoric acid chromate treatment using a compound and three components of phosphoric acid is good. Or the chemical conversion treatment agent which contains metals, such as molybdenum, titanium, a zircon, or a metal salt in the resin component containing a phenol resin at least was favorable. Due to the formation of the acid-resistant film, delamination between aluminum and the base material layer during embossing is prevented, and the aluminum surface is dissolved and corroded by hydrogen fluoride generated by the reaction between the battery electrolyte and moisture. In particular, the aluminum oxide existing on the surface of aluminum is prevented from being dissolved and corroded, and the adhesion (wetting property) of the aluminum surface is improved, and the base material layer 11 and the aluminum 12 at the time of embossing and heat sealing. The effect of preventing delamination on the inner surface of aluminum by hydrogen fluoride generated by the reaction between electrolyte and moisture was obtained.
As a result of conducting a chemical conversion treatment on the aluminum surface using various substances and studying the effect thereof, among the acid-resistant film forming substances, it is composed of three components of a phenol resin, a chromium fluoride (3) compound, and phosphoric acid. The treatment with phosphoric acid chromate using the sample was good.
Or the chemical conversion treatment agent which contains metals, such as molybdenum, titanium, a zircon, or a metal salt in the resin component containing a phenol resin at least was favorable.
[0021]
When the exterior body is a pouch type, the chemical conversion treatment of aluminum may be performed on one side only on the sealant layer side or on both sides of the base material layer side and the sealant layer side. When the battery outer body is an embossed type, it is possible to prevent delamination between the aluminum and the base material layer during embossing or in the heat sealing process after molding by chemical conversion treatment on both sides of the aluminum. it can.
[0022]
As described above, the sealant layer in the battery packaging material of the present invention is made of metallocene-based linear low-density polyethylene and coextruded and laminated using unsaturated carboxylic acid grafted polyethylene as an adhesive resin.
[0023]
【Example】
The battery packaging material of the present invention will be described more specifically with reference to examples.
(1) Structure of battery packaging material In both the example and comparative example, 25 μm stretched nylon and 40 μm thick aluminum subjected to chemical conversion treatment on both sides are dry laminated unless otherwise specified. An adhesive resin layer and a sealant layer were formed on the opposite surface of each under the respective conditions.
(2) The chemical conversion treatment applied to the barrier layer of the chemical conversion treatment exterior body is a roll coating method in which the aqueous solution composed of a phenol resin, a chromium fluoride (3) compound, and phosphoric acid is used as the treatment liquid in both Examples and Comparative Examples. Was applied and baked under the condition that the film temperature was 180 ° C. or higher. The application amount of chromium is 5 mg / m ² (dry weight).
In both Examples and Comparative Examples, after forming a laminate, the laminate was heated to a temperature equal to or higher than the softening point of the adhesive resin (acid-modified polyethylene) to stabilize the laminate strength.
(3) Type of exterior body Both the examples and comparative examples were evaluated as embossed exterior bodies. The shape was a single-sided embossed type, and the shape of the concave portion (cavity) of the mold was 30 mm × 50 mm, and the moldability was evaluated by press molding.
(4) Abbreviation LL: Linear low-density polyethylene metallocene LL: Metallocene-based linear low-density polyethylene LD: Low-density polyethylene MD: Medium-density polyethylene (+): Blend resin, the number after the abbreviation is the weight of the blend %.
[Example 1]
A laminate of Example 1 was obtained by co-extrusion using acid-modified polyethylene (15 μm) as an adhesive resin and metallocene LL (30 μm) as a sealant resin.
[Example 2]
A laminate of Example 2 was obtained by co-extrusion using acid-modified polyethylene (15 μm) as an adhesive resin and a blend resin of (metallocene LL90 + LD10) as a sealant to a thickness of 30 μm.
[Example 3]
The laminate of Example 3 was obtained by co-extrusion using acid-modified polyethylene (15 μm) as an adhesive resin and a blend resin of (metallocene LL70 + LD30) as a sealant to a thickness of 30 μm.
[Example 4]
A laminate of Example 4 was obtained by co-extrusion using acid-modified polyethylene (15 μm) as an adhesive resin and a blend resin of (metallocene LL50 + LD50) as a sealant to a thickness of 30 μm.
[0024]
[Comparative Example 1]
A laminate of Comparative Example 1 was obtained by sandwich lamination using acid-modified polyethylene (15 μm) as an adhesive resin and a film made of LL (30 μm) as a sealant layer.
[Comparative Example 2]
A laminate of Comparative Example 2 was obtained by sandwich lamination using acid-modified polyethylene (15 μm) as an adhesive resin and a film made of a blend resin of (LL50 + LD50) as a sealant layer (30 μm).
[Comparative Example 3]
A laminate of Comparative Example 3 was obtained by sandwich lamination using acid-modified polyethylene (15 μm) as an adhesive resin and a film made of MD (30 μm) as a sealant layer.
[Comparative Example 4]
A laminate of Comparative Example 4 was obtained by co-extrusion using acid-modified polyethylene (15 μm) as an adhesive resin and LL (30 μm) as a sealant resin.
[Comparative Example 5]
A stretched nylon film (thickness 25 μm) is bonded to one side of aluminum 40 μm that is not subjected to chemical conversion treatment by a dry laminating method. A laminate of Comparative Example 5 was obtained by coextruding the resin as a sealant to a thickness of 30 μm.
[0025]
<Evaluation items>
1) Formability 50 samples of each specimen were molded, and the amount of molding indentation (depth) at which pinholes and wrinkles did not occur stably was measured.
2) Punching workability With an upper punch and a lower die (punch size 120 × 70 mm), the punch push-in amount at which burrs and ties were not generated was measured.
3) Confirmation of inner surface anti-electrolytic solution 3 g of the contents were sealed in a molded product having a depth of 4 mm and a length and width of 50 mm × 30 mm, and the presence or absence of delamination was confirmed after storage at 85 ° C. for 24 hours.
Contents: Mixed solution of ethylene carbonate, diethyl carbonate, and dimethyl carbonate (1: 1: 1) so as to be 1M LiPF _{6 in the} electrolyte.
[0026]
<Results> As shown in Table 1.
[Table 1]

In Examples 1 to 4, the molding depth, the punch push-in amount, and the inner surface anti-electrolytic solution were good, but in particular, Example 4 was excellent. Comparative Example 1, Comparative Example 2 has poor punching suitability, Comparative Example 3 moldability inferior both punching suitability, Comparative Example 4 is inferior in moldability. Comparative Example 5, moldability, although vent suitability is good, delamination occurs.
[0027]
【The invention's effect】
At least the sealant layer of the battery packaging material of the present invention is made of metallocene linear low-density polyethylene, and coextruded and laminated with polyethylene graft-modified with unsaturated carboxylic acid as an adhesive resin, without impairing embossability. It was possible to improve the die set punching suitability in the exterior body forming process.
[Brief description of the drawings]
1A and 1B are diagrams illustrating a battery packaging material of the present invention, in which FIG. 1A is a cross-sectional view showing a layer structure, and FIG. 1B is a cross-sectional view showing another layer structure.
FIGS. 2A and 2B are diagrams for explaining an example of extraction when forming a battery outer package, in which FIG. 2A is a perspective view of the battery, and FIG. 2B is a perspective view of the battery main body and the outer package before the battery main body is inserted; (C) It is a top view which shows the extraction shape of an exterior body.
FIG. 3 is a perspective view for explaining a pouch-type exterior body of a battery.
FIG. 4 is a perspective view illustrating an embossed type exterior body of a battery.
[5] will be described molding in embossed type, (a) a perspective view, (b) embossing the molded outer body, (c) X ₁ -X ₁ part cross-sectional view, with (d) Y ₁ part enlarged view is there.
FIG. 6 is a conceptual diagram showing an example of coextrusion lamination of a sealant part.
[Explanation of symbols]
T Disconnected wire m Folded wire 1 Battery 2 Battery body 3 Cell (power storage unit)
4 Lead wire (electrode)
DESCRIPTION OF SYMBOLS 5 Exterior body 5V Tray part 5F Lid part 6 Lead wire film 7 Recessed part 8 Side wall part 9 Seal part 10 Laminated body (battery packaging material)
DESCRIPTION OF SYMBOLS 11 Base material layer 12 Barrier layer 13 Adhesive resin layer 14 Sealant layer 15 Chemical conversion treatment layer 16 Dry laminate layer 20 of base material layer and barrier layer Press molding part 21 Male mold 22 Female mold 23 Cavity 30 Co-extrusion laminator 31a Adhesive resin Extruder 31b Sealant resin extruder 32 Die 33 Molten resin film 34 of sealant part Chill roll 35 Backup roll 36 Intermediate laminated body 37 Laminated body winding

Claims (4)

In battery packaging in which the battery body is inserted and the periphery is sealed by heat sealing, the packaging material forming the exterior body is composed of at least a base material layer, an adhesive layer, a barrier layer, a chemical conversion treatment layer, an adhesive resin layer, and a sealant layer A battery packaging material , wherein an adhesive resin layer and a sealant layer are formed by coextrusion , and the sealant layer is a metallocene linear low-density polyethylene resin . In battery packaging in which the battery body is inserted and the periphery is sealed by heat sealing, the packaging material forming the exterior body is composed of at least a base material layer, an adhesive layer, a barrier layer, a chemical conversion treatment layer, an adhesive resin layer, and a sealant layer The adhesive resin layer and the sealant layer are formed by coextrusion , the adhesive resin layer is a polyethylene resin graft-polymerized with an unsaturated carboxylic acid, and the sealant layer is a metallocene linear A battery packaging material characterized by being a low-density polyethylene resin . In battery packaging in which the battery body is inserted and the periphery is sealed by heat sealing, the packaging material forming the exterior body is composed of at least a base material layer, an adhesive layer, a barrier layer, a chemical conversion treatment layer, an adhesive resin layer, and a sealant layer The adhesive resin layer and the sealant layer are formed by coextrusion , the adhesive resin layer is acid-modified polyethylene, and the sealant layer is a metallocene linear low-density polyethylene resin. Battery packaging material. 4. The battery packaging material according to claim 1 , wherein the sealant layer is a metallocene linear low-density polyethylene resin to which low-density polyethylene is added in an amount of 10 wt% to 50 wt% .

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