CN107487050A - Housing material diaphragm seal, housing material and the manufacture method of electrical storage device - Google Patents

Abstract

The present invention relates to a sealing film for an outer packaging material of an electrical storage device, an outer packaging material, and a manufacturing method. A sealing film for an exterior material of an electrical storage device is composed of a first unstretched film layer that forms the innermost layer of the exterior material, and a surface laminated on one side of the first unstretched film layer. A laminate of two or more layers of the second unstretched film layer is formed; the first unstretched film layer contains a random copolymer and a lubricant, and the random copolymer contains propylene and other copolymerization components other than propylene as Copolymerized component; the second unstretched film layer contains a block copolymer and a lubricant, the block copolymer contains propylene and other copolymerized components other than propylene as a copolymerized component; the lubricant in the first unstretched film layer The content concentration of the lubricant in the second unstretched film layer is 200 ppm to 3000 ppm, and the content concentration of the lubricant in the second unstretched film layer is 500 ppm to 5000 ppm.

Description

Sealing film for outer packaging material of power storage device, outer packaging material, and manufacturing method

technical field

The present invention relates to a sealing film for constituting an exterior material of an electrical storage device for use in smartphones and tablets, and a method of manufacturing an electrical storage device outer packaging material using the sealing film. Batteries and capacitors used in portable devices such as computers; batteries and capacitors used for power storage of hybrid vehicles, electric vehicles, wind power generation, solar power generation, and nighttime power.

Background technique

In recent years, with the reduction in thickness and weight of mobile electronic devices such as smartphones and tablet terminals, lithium ion secondary batteries, lithium polymer secondary batteries, lithium ion capacitors (lithium ion capacitors) mounted on the above mobile electronic devices , Electric double-layer capacitors and other electrical storage device outer packaging materials are replaced by laminates consisting of heat-resistant resin layer/adhesive layer/metal foil layer/adhesive layer/thermoplastic resin layer (inner sealing layer) Traditional metal cans. In addition, power sources such as electric vehicles, large power sources for storage of electricity, capacitors, and the like are increasingly being packaged using the laminate (outer packaging material) having the above-mentioned structure. By stretching or deep drawing the laminate, it can be molded into a three-dimensional shape such as a substantially rectangular parallelepiped. By molding into such a three-dimensional shape, a storage space for housing the main body of the power storage device can be ensured.

In order to form such a three-dimensional shape in a good state without pinholes, cracks, etc., it is desired to improve the sliding properties of the surface of the inner sealant layer. As a technique for improving the sliding properties of the surface of the inner sealant layer to ensure good moldability, a laminated material for secondary battery containers has been proposed in which an exterior resin film, a first adhesive layer, and a chemical conversion-treated aluminum foil are sequentially laminated , a laminate made of a second adhesive layer and a sealing film, wherein the sealing film is formed of a random copolymer of propylene and α-olefin with an α-olefin content of 2 to 10% by weight, and the The laminate contains 1000 ppm to 5000 ppm of lubricant (see Patent Document 1).

Patent Document 1: Japanese Patent Laid-Open No. 2003-288865

Contents of the invention

The problem to be solved by the invention

However, in the prior art described above, it is difficult to control the amount of lubricant deposited on the surface due to the heating and holding time and storage period in the production process of the outer packaging material (laminated material). Excessive precipitation occurs on the surface, so when the packaging material is molded, the lubricant adheres and accumulates on the molding surface of the molding die to generate white powder (white powder caused by the lubricant). If it becomes the state that such white powder adheres and accumulates on the molding surface, it is difficult to perform good molding. Therefore, every time white powder adheres and accumulates, it must be cleaned to remove the white powder. There is such a problem that productivity decreases.

Of course, if the amount of lubricant added (lubricant content rate) is reduced, the adhesion and accumulation of white powder can be suppressed, but in this case, the problem that the deposited amount of lubricant on the surface is insufficient and the moldability deteriorates occurs. As described above, it has been difficult to achieve both excellent moldability and suppression of white powder exposure on the surface of the packaging material.

The present invention has been made in view of the above-mentioned technical background, and an object of the present invention is to provide a sealing film for an exterior material of an electrical storage device, an exterior material for an electrical storage device, and a manufacturing method thereof that can suppress deposition on the surface of an exterior material. The reduction in the amount of lubricant ensures good sliding properties during molding, resulting in excellent moldability, and it is difficult to expose white powder on the surface.

means of solving problems

In order to achieve the above objects, the present invention provides the following means.

[1] A sealing film for an exterior material of an electrical storage device, comprising a first unstretched film layer and a second unstretched film layer laminated on one side of the first unstretched film layer. A laminate of two or more layers of the stretched film layer is formed,

said first unstretched film layer forms an innermost layer of the outer packaging material,

The first unstretched film layer contains a random copolymer containing propylene and other copolymer components other than propylene as copolymer components, and a lubricant,

The second unstretched film layer contains a block copolymer containing propylene and other copolymer components other than propylene as copolymer components, and a lubricant,

The content concentration of the lubricant in the first unstretched film layer is 200 ppm to 3000 ppm, and the content concentration of the lubricant in the second unstretched film layer is 500 ppm to 5000 ppm.

[2] A sealing film for an exterior material of an electrical storage device, comprising a first unstretched film layer laminated on one side of the second unstretched film layer. A film layer and a laminate of three or more layers of the first unstretched film layer laminated on the other side of the second unstretched film layer,

The first unstretched film layer on one side of the first unstretched film layer laminated on both sides of the second unstretched film layer forms the innermost layer of the outer packaging material,

The first unstretched film layer contains a random copolymer containing propylene and other copolymer components other than propylene as copolymer components, and a lubricant,

The second unstretched film layer contains a block copolymer containing propylene and other copolymer components other than propylene as copolymer components, and a lubricant,

The content concentration of the lubricant in the first unstretched film layer is 200 ppm to 3000 ppm, and the content concentration of the lubricant in the second unstretched film layer is 500 ppm to 5000 ppm.

[3] The sealing film for an outer packaging material of an electrical storage device according to item 1 or 2 above, wherein the lubricant in the second unstretched film layer contains a concentration of that of the innermost layer of the outer packaging material. The lubricant in the first unstretched film layer contains 0.5 times to 5 times the concentration.

[4] The exterior material for an electrical storage device, comprising an inner sealant layer formed of the sealant film according to any one of the preceding items 1 to 3, and a metal laminated on one side of the inner sealant layer. foil layer.

[5] An outer packaging material for an electrical storage device, comprising a heat-resistant resin layer as an outer layer, an inner sealing layer formed of the sealing film according to any one of the preceding items 1 to 3, and an outer sealing layer disposed on The metal foil layer between them.

[6] The outer packaging material for an electrical storage device according to item 4 or 5 above, wherein the amount of lubricant present on the surface of the first unstretched film layer forming the innermost layer of the outer packaging material is 0.1 μg /cm ² to 1.0 μg/cm ² range.

[7] An exterior case for an electrical storage device formed from a molded body of the exterior material described in any one of the preceding items 4 to 6.

[8] A method of manufacturing an outer packaging material for an electrical storage device, comprising:

A step of preparing a laminate obtained by laminating the sealing film and the metal foil according to any one of the preceding items 1 to 3 via a first adhesive; and

In the aging step, the laminate is heat-treated to obtain an exterior material for an electrical storage device.

[9] The method of manufacturing an exterior material for an electrical storage device according to item 8 above, wherein the first adhesive is a thermosetting adhesive.

[10] A method for manufacturing an outer packaging material for an electrical storage device, comprising:

A step of preparing a laminate in which a heat-resistant resin film is laminated on one surface of the metal foil via a second adhesive, and the other surface of the metal foil is interposed The sealing film described in any one of the preceding items 1 to 3 is laminated with a first adhesive; and

In the aging step, the laminate is heat-treated to obtain an exterior material for an electrical storage device.

[11] The method of manufacturing an exterior material for an electrical storage device according to item 10 above, wherein the first adhesive is a thermosetting adhesive, and the second adhesive is a thermosetting adhesive.

[12] The method for producing an exterior material for an electrical storage device according to any one of items 8 to 11 above, wherein the innermost The amount of lubricant on the surface of the first unstretched film layer of the layer is in the range of 0.1 μg/cm ² to 1.0 μg/cm ² .

The effect of the invention

In the inventions of [1] and [2], it is possible to suppress the decrease in the amount of (precipitated) lubricant present on the surface of the aging-treated outer packaging material (surface 7a of the innermost layer of the inner sealant layer), and to reduce the amount of lubricant during molding. Good slidability can be ensured at this time, so that moldability is excellent, and white powder is not easily exposed on the surface of the outer packaging material (surface 7a of the innermost layer of the inner sealing layer). In addition, since the amount of lubricant present on the surface of the aging-treated outer packaging material does not change even when subjected to heat history during transportation, storage, etc., it is possible to provide an outer packaging material stably having excellent moldability.

In the invention of [3], the lubricant content concentration in the second unstretched film layer is 0.5 to 5 times the lubricant content concentration in the first unstretched film layer forming the innermost layer of the packaging material. times, during the aging treatment, by being more than 0.5 times, the lubricant can be suppressed from the first unstretched film layer 7 of the innermost layer to the second unstretched film layer 8 toward the interface ( The interface of two film layers 7,8) concentrates to move, and by being below 5 times, lubricant can be suppressed from the second unstretched film layer 8 to the first unstretched film of the innermost layer due to the reason of lubricant concentration gradient. Layer 7 moves toward the interface (the interface of the two film layers 7, 8) intensively, and the amount of lubricant present on the surface 7a of the first unstretched film layer that forms the innermost layer of the outer packaging material after the aging treatment can be controlled to be 0.1 The range of μg/cm ² to 1.0 μg/cm ² .

According to the inventions of [4] and [5], it is possible to provide the following outer packaging material for an electrical storage device: the presence (precipitated ) The reduction of the amount of lubricant can ensure good sliding properties during molding, so that the moldability is excellent, and the surface of the outer packaging material (the surface 7a of the innermost layer of the inner sealing layer) is not easy to expose white powder.

In addition, in the invention of [5], since the heat-resistant resin layer is also provided as the outer layer, the insulation of the side opposite to the inner sealing layer of the metal foil layer can be sufficiently ensured, and the outer packaging material can be improved. Physical strength and impact resistance.

According to the invention of [6], it is possible to provide an exterior material for an electrical storage device capable of exhibiting better slidability during molding, further securing better moldability, and preventing exposure of white powder.

According to the invention of [7], it is possible to provide an exterior case for an electrical storage device that can be molded well and is less likely to expose white powder on the surface of the exterior case (the surface of the innermost layer of the inner sealant layer).

According to the inventions of [8] to [11], it is possible to manufacture the following outer packaging material for an electrical storage device in which the presence (precipitated ) The reduction of the amount of lubricant can ensure good sliding properties during molding, so that the moldability is excellent, and the surface of the outer packaging material (the surface 7a of the innermost layer of the inner sealing layer) is not easy to expose white powder.

In addition, in the inventions of [10] and [11], since the heat-resistant resin layer is further provided as the outer layer, the insulation of the side opposite to the inner sealing layer of the metal foil layer can be sufficiently ensured, and the Improve the physical strength and impact resistance of the outer packaging material.

In the invention of [12], since the amount of lubricant present on the surface of the innermost layer is in the range of 0.1 μg/cm ² to 1.0 μg/cm ² , it is possible to exhibit better sliding properties during molding and further ensure Good formability and can prevent white powder from being exposed as an outer packaging material for electrical storage devices. In addition, since the amount of lubricant (0.1 μg/cm ² to 1.0 μg/cm ² ) present on the surface of the obtained electrical storage device outer packaging material does not change even when it is subjected to heat history during transportation, storage, etc., it is possible to provide a stable It is an outer packaging material with excellent formability.

Description of drawings

FIG. 1 is a cross-sectional view showing one embodiment of an exterior material for an electrical storage device according to the present invention.

2 is a cross-sectional view showing another embodiment of the exterior material for an electrical storage device according to the present invention.

Fig. 3 is a cross-sectional view showing one embodiment of the power storage device according to the present invention.

Fig. 4 is a state in which the outer packaging material (flat outer packaging material), the main body of the electrical storage device, and the outer casing (a molded body molded into a three-dimensional shape) constituting the electrical storage device of Fig. 3 are separated before being heat-sealed; The perspective view shown.

Explanation of reference signs

1...Outer packaging materials for power storage devices

2...Heat-resistant resin layer (outer layer)

3... Inner sealing layer (sealing film) (inner layer)

4...metal foil layer

5...Second adhesive layer (outer adhesive layer)

6...First adhesive layer (inside adhesive layer)

7...the first unstretched film layer (innermost layer)

7a... the surface of the first unstretched film layer (the surface of the innermost layer of the outer packaging material)

8...second unstretched film layer

9...First unstretched film layer (metal foil layer side)

10...External case for power storage device (molded body)

15...exterior components

30...Power storage device

31...Main part of power storage device

detailed description

A first embodiment of a sealing film for an exterior material of an electrical storage device according to the present invention is shown in FIG. 1 . The sealing film 3 is composed of a first unstretched film layer 7 forming the innermost layer of the outer packaging material 1, and a second unstretched film layer laminated on one side of the first unstretched film layer 7. A laminate of film layers 8 is formed, the first unstretched film layer 7 contains a random copolymer and a lubricant, the random copolymer contains propylene and other copolymer components other than propylene as copolymer components, and the second The bi-unstretched film layer 8 contains a block copolymer containing propylene and other copolymer components other than propylene as copolymer components, and a lubricant.

Moreover, the 2nd Embodiment of the sealing film for exterior materials of the electrical storage device concerning this invention is shown in FIG. 2. The sealing film 3 is composed of a second unstretched film layer 8, a first unstretched film layer 7 laminated on one side of the second unstretched film layer, and a The laminate of the first unstretched film layer 9 on the other side of the second unstretched film layer is formed; the first unstretched film layer 7 on one side forms the innermost layer; the first unstretched film layer 7, 9 contains a random copolymer and a lubricant, and the random copolymer contains propylene and other copolymer components other than propylene as copolymer components; the second unstretched The film layer 8 contains a block copolymer containing propylene and other copolymer components other than propylene as copolymer components, and a lubricant.

The first unstretched film layers 7 and 9 contain a random copolymer containing "propylene" and "copolymerization components other than propylene" as copolymerization components, and a lubricant. The random copolymer is not particularly limited as the "copolymerization component other than propylene", and examples thereof include ethylene, 1-butene, 1-hexene, 1-pentene, 4-methyl -Olefin components such as 1-pentene, butadiene, etc.

The second unstretched film layer 8 contains a block copolymer containing "propylene" and "copolymerization components other than propylene" as copolymerization components, and a lubricant. Regarding the block copolymer, the "copolymerization components other than propylene" are not particularly limited, and examples thereof include ethylene, 1-butene, 1-hexene, 1-pentene, 4-methyl -Olefin components such as 1-pentene, butadiene, etc.

Furthermore, it is important for the sealing film 3 according to the present invention to set the lubricant content in the first unstretched film layers 7 and 9 to 200 ppm to 3000 ppm, and to set the lubricant in the second unstretched film layers The content concentration of the lubricant in the stretched film layer 8 is set to 500 ppm to 5000 ppm. By satisfying such a condition, when the aging treatment for curing the adhesive is performed, the lubricant present in the first unstretched film layer 7 can be suppressed from migrating into the second unstretched film layer 8, thereby ensuring The amount of lubricant precipitated on the surface of the wrapping material (the surface 7a of the first unstretched film layer as the innermost layer) ensures good sliding properties during molding of the wrapping material, resulting in excellent moldability. If the content concentration of the lubricant in the first unstretched film layer 7 is less than 200 ppm, the amount of lubricant present on the surface 7a of the innermost layer becomes insufficient after the aging treatment for curing the adhesive, As a result, excellent moldability cannot be obtained. If it exceeds 3000ppm, after the aging treatment for curing the adhesive, white powder will be remarkably generated on the surface 7a of the innermost layer, and it is necessary to clean and remove the white powder. There is a problem of lowering productivity, and when used as an outer packaging material, there are also problems that the adhesive force with the metal foil layer is lowered, and the contamination of the electrolytic solution is likely to occur. In addition, when the content concentration of the lubricant in the second unstretched film layer 8 is less than 500 ppm, the lubricant is easily released from the innermost first unstretched film layer during the aging treatment for curing the adhesive. 7 moves to the second unstretched film layer 8, the amount of lubricant existing on the surface 7a of the innermost layer becomes insufficient, resulting in poor sliding properties during molding, and if it exceeds 5000ppm, it will be used to cure the adhesive. During the ripening treatment, the lubricant easily moves from the second unstretched film layer 8 to the first unstretched film layer 7, 9, and white powder pollution occurs in the device in production. When used as an outer packaging material, it is easy to produce the same The adhesion of the metal foil layer is reduced, and the electrolyte is polluted.

Wherein, the content concentration of the lubricant in the first unstretched film layers 7 and 9 is preferably in the range of 300 ppm to 2700 ppm, more preferably in the range of 800 ppm to 1200 ppm. In addition, the content concentration of the lubricant in the second unstretched film layer 8 is preferably in the range of 700 ppm to 4500 ppm, more preferably in the range of 800 ppm to 2700 ppm.

In the sealing film 3 involved in the present invention, the lubricant in the second unstretched film layer 8 preferably has a concentration equal to the lubricating agent in the first unstretched film layer 7 forming the innermost layer of the outer packaging material 1. The agent contains 0.5 times to 5 times the concentration. By being 0.5 times or more, when performing aging treatment for curing the adhesive, it can be suppressed that the lubricant moves from the first unstretched film layer 7 of the innermost layer to the second unstretched film layer due to the lubricant concentration gradient. Stretch film layer 8 moves toward the interface (the interface of two film layers 7, 8) intensively, thereby the amount of lubricant present on the surface 7a of the innermost layer becomes sufficient, and more excellent moldability can be obtained, and the pass is 5 times or less, When the aging treatment for curing the adhesive is carried out, the lubricant can be suppressed from moving from the second unstretched film layer 8 to the innermost first unstretched film layer 7 toward the interface due to the lubricant concentration gradient. (The interface between the two film layers 7, 8) moves intensively, and the fluctuation of the lubricant content of the innermost first unstretched film layer 7 can be sufficiently suppressed. Wherein, the lubricant concentration in the second unstretched film layer 8 is more preferably 1.0 times the lubricant concentration in the first unstretched film layer 7 forming the innermost layer of the outer packaging material 1. ~3.0 times.

The lubricant is not particularly limited, and examples thereof include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylol amides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, fatty acid ester amides, aromatic Department of bisamides and so on. As the lubricant, only one type may be used, or a plurality of types may be mixed and used.

It does not specifically limit as said saturated fatty acid amide, For example, lauramide, palmitamide, stearamide, behenamide, hydroxystearamide etc. are mentioned. It does not specifically limit as said unsaturated fatty acid amide, For example, oleic acid amide, erucic acid amide, etc. are mentioned.

The substituted amides are not particularly limited, and examples include N-oleyl palmitamide, N-octadecyl stearamide, N-octadecyl oleamide, N-oleyl stearamide, N-octadecyl erucamide, etc. Moreover, it does not specifically limit as said methylol amide, For example, methylolstearamide etc. are mentioned.

The saturated fatty acid bisamide is not particularly limited, and examples thereof include methylene bis-stearamide, ethylene bis-decanoamide, ethylene bis-lauramide, ethylene bis-stearamide, and ethylene bis-hydroxystearamide. , Ethylene bis-behenamide, Hexamethylene bis-stearamide, Hexamethylene bis-behenamide, Hexamethylene hydroxystearamide, N, N'-Dioctadecyl adipamide, N , N'-Dioctadecyl Sebacamide, etc.

The unsaturated fatty acid bisamide is not particularly limited, and examples thereof include ethylene bisoleic acid amide, ethylene biserucic acid amide, hexamethylene bisoleic acid amide, N,N'-bisoleyldecane diamide, etc.

It does not specifically limit as said fatty acid ester amide, For example, stearamidoethyl stearate etc. are mentioned. The aromatic bisamide is not particularly limited, and examples thereof include m-xylylene bisstearamide, m-xylylene bishydroxystearamide, N,N'-dioctadecyl m- Phthalamide, etc.

Preferably, the thickness of the sealing film 3 is set to 10 μm to 100 μm. By setting it to 10 μm or more, the occurrence of pinholes can be sufficiently prevented, and by setting it to 100 μm or less, it is possible to reduce the amount of resin used and reduce costs.

When using the 2-layer laminate structure of FIG. 1 as the sealing film 3, the ratio of the thicknesses of the 2 layers is preferably set to the thickness of the first unstretched film layer 7/the thickness of the second unstretched film layer 8 = the range of 5 to 90/95 to 10, especially preferably set to the range of thickness of the first unstretched film layer 7 /thickness of the second unstretched film layer 8 = 5 to 40/95 to 60.

In addition, when using the three-layer laminated structure of FIG. 2 as the sealing film 3, the ratio of the thicknesses of the three layers is preferably set to the thickness of the first unstretched film layer 7/the second unstretched film layer 8 The thickness of the thickness/the thickness of the first unstretched film layer 9=5～45/90～10/5～45 range, wherein, particularly preferably set as the thickness of the first unstretched film layer 7/the second unstretched film layer Thickness of the stretched film layer 8/thickness of the first unstretched film layer 9=5-20/90-60/5-20.

The first unstretched film layer 7 forming the innermost layer may further contain anti-blocking agents. In addition, an antiblocking agent may be contained in both the first unstretched film layer 7 forming the innermost layer and the first unstretched film layer 9 on the metal foil layer side. It does not specifically limit as said antiblocking agent, For example, a silica particle, an acrylic resin particle, an aluminum silicate particle etc. are mentioned. The particle diameter of the anti-blocking agent is preferably in the range of 0.1 μm to 10 μm in terms of average particle diameter, and more preferably in the range of 1 μm to 5 μm in terms of average particle diameter. When the antiblocking agent is contained in the first unstretched film layers 7 and 9, the concentration thereof is preferably set to 100 ppm to 5000 ppm.

By making the first unstretched film layer 7 forming the innermost layer contain the anti-blocking agent (particles), microscopic protrusions are formed on the surface 7a of the innermost layer 7 to reduce the contact area between the films, Thereby, blocking of the sealing films can be suppressed. In addition, by containing an anti-blocking agent (particles) together with the lubricant, the sliding properties at the time of the molding can be further improved.

Preferably, the sealing film 3 is manufactured by multi-layer extrusion molding, inflation molding, T-die cast film molding and other molding methods.

The exterior material 1 for an electrical storage device according to the present invention is produced using the sealing film having the above configuration. A laminate was prepared in which the sealing film 3 and the metal foil 4 of the first embodiment described above were laminated via a first adhesive (inside adhesive) 6 . At this time, the second unstretched film layer 8 of the sealing film 3 is in contact with the first adhesive 6 (see FIG. 1 ). Next, the obtained laminate is subjected to heat treatment (aging treatment), thereby obtaining the exterior material 1 for an electrical storage device of the present invention having the configuration shown in FIG. 1 .

In addition, a laminated body having a structure in which a heat-resistant resin film (outer layer) 2 is laminated on one side of the metal foil 4 via a second adhesive (outer adhesive) 5, and The sealing film 3 of the second embodiment described above is laminated on the other surface of the metal foil 4 via a first adhesive (inside adhesive) 6 . At this time, the first unstretched film layer 9 of the sealing film 3 is in contact with the first adhesive (inside adhesive) 6 (see FIG. 2 ). That is, the first unstretched film layer 7 on the other side of the sealing film 3 forms the innermost layer (see FIG. 2 ). Next, the obtained laminate is subjected to heat treatment (aging treatment), thereby obtaining the exterior material 1 for an electrical storage device of the present invention having the configuration shown in FIG. 2 .

Although it does not specifically limit as said 1st adhesive agent (inside adhesive agent) 6, For example, a thermosetting adhesive agent etc. are mentioned. Moreover, it does not specifically limit as said 2nd adhesive agent (outer adhesive agent) 5, For example, a thermosetting adhesive agent etc. are mentioned. It does not specifically limit as said thermosetting adhesive agent, For example, an olefin type adhesive agent, an epoxy type adhesive agent, an acrylic type adhesive agent etc. are mentioned.

The heating temperature of the aging treatment is preferably set to 65° C. or lower, and more preferably set to 65° C. or less from the viewpoint of maintaining the degree of curing of the adhesive and the preferred amount of lubricant present on the surface 7 a of the outer packaging material. 35℃～45℃. In addition, since the curing time varies depending on the type of adhesive, the heating time for the aging treatment should be the time at which sufficient adhesive strength can be obtained according to the type of adhesive. The above is enough, and considering the development period (lead time) of the process, it is preferable that the heating time be as short as possible within the range where sufficient adhesive strength can be obtained.

The exterior material 1 for an electrical storage device of the present invention obtained through such an aging treatment has a configuration in which a second adhesive layer (outer adhesive layer) is interposed on one side of the metal foil layer 4 . 5. A heat-resistant resin layer (outer layer) 2 is laminated and integrated, and the other side of the metal foil layer 4 is laminated via a first adhesive layer (inner adhesive layer) 6. An inner sealing layer (sealing film) (inner layer) 3 is formed (see FIGS. 1 and 2 ).

In the electrical storage device exterior material 1 obtained through the aging treatment, the lubricant content in the first unstretched film layer of the sealing film 3 used in the production was set to 200 ppm as described above. ~ 3000ppm, the content concentration of the lubricant in the second unstretched film layer is set to 500ppm ~ 5000ppm, so it exists in the first unstretched film layer forming the innermost layer of the electrical storage device outer packaging material 1 after aging treatment. The amount of lubricant on the surface 7a of the stretch film layer 7 can be controlled within the range of 0.1 μg/cm ² to 1.0 μg/cm ² . Therefore, in the obtained exterior material 1 for an electrical storage device, the decrease in the amount of (precipitated) lubricant existing on the surface (the surface 7a of the innermost layer of the inner seal layer) can be suppressed, and good sliding properties can be ensured during molding, thereby It has excellent moldability, and white powder is less likely to be exposed on the surface of the outer packaging material (surface 7a of the innermost layer of the inner sealant layer).

In the exterior material 1 for an electrical storage device, the kinetic friction coefficient of the surface 7 a of the first unstretched film layer (innermost layer) 7 is preferably within a range of 0.10 to 0.50. When it is 0.50 or less, slidability can be improved and good formability can be ensured, and when it is 0.10 or more, the amount of lubricant seeping out to the surface 7 a of the innermost layer can be reduced.

The exterior material 1 for electrical storage devices of this invention can be used as an exterior material for lithium ion secondary batteries, for example. The outer packaging material 1 for the electrical storage device can be used as an outer packaging material without molding, or it can be used as an outer casing 10 by forming such as deep drawing molding or stretch molding (see FIG. 4 ). ).

In the exterior material 1 for an electrical storage device according to the present invention, the inner sealing layer (inner layer) 3 plays a role of having excellent resistance to highly corrosive electrolytes and the like used in lithium-ion secondary batteries and the like. Chemical resistance, while imparting heat sealability to the outer packaging material.

In addition, the heat-resistant resin layer (base material layer; outer layer) 2 is not an essential constituent layer, but it is preferably used on the other side of the metal foil layer 4 (the side opposite to the inner sealant layer). surface) on which a heat-resistant resin layer 2 is laminated via a second adhesive layer (outer adhesive layer) 5 (see FIGS. 1 and 2 ). By providing such a heat-resistant resin layer 2, the insulation on the other side of the metal foil layer 4 (the side opposite to the inner sealing layer) can be sufficiently ensured, and the physical properties of the outer packaging material 1 can be improved. strength and impact resistance.

As the heat-resistant resin constituting the heat-resistant resin layer (base material layer; outer layer) 2, a heat-resistant resin that does not melt at the heat-sealing temperature when heat-sealing the outer packaging material is used. As the heat-resistant resin, it is preferable to use a heat-resistant resin having a melting point higher than the melting point of the block copolymer constituting the second unstretched film layer 8 by 10° C. The block copolymer of the stretch film layer 8 is a heat-resistant resin whose melting point is 20° C. or higher.

The heat-resistant resin layer (outer layer) 2 is not particularly limited, and examples thereof include polyamide films such as nylon films, polyester films, and the like, and stretched films of these films can be preferably used. Among them, as the heat-resistant resin layer 2, it is particularly preferable to use a biaxially stretched polyamide film such as a biaxially stretched nylon film, a biaxially stretched polybutylene terephthalate (PBT) film, a biaxially stretched Stretched polyethylene terephthalate (PET) film or biaxially stretched polyethylene naphthalate (PEN) film. It does not specifically limit as said nylon film, For example, a nylon 6 film, a nylon 6,6 film, a nylon MXD film etc. are mentioned. It should be noted that the heat-resistant resin layer 2 may be formed of a single layer, or may be formed of, for example, a multilayer of polyester film/polyamide film (multilayer of PET film/nylon film, etc.).

The thickness of the heat-resistant resin layer (outer layer) 2 is preferably 2 μm to 50 μm. When a polyester film is used, the thickness is preferably 2 μm to 50 μm, and when a nylon film is used, the thickness is preferably 7 μm to 50 μm. By setting the above-mentioned preferable lower limit value or more, sufficient strength as the outer packaging material can be ensured, and by setting the above-mentioned preferable upper limit value or less, the stress during molding such as stretch molding and deep-drawing molding can be reduced. , so that the formability can be improved.

In the exterior material 1 for an electrical storage device according to the present invention, on the surface of the heat-resistant resin layer (outer layer) 2 opposite to the metal foil layer 4, the exterior material for forming an electrical storage device is attached. The lubricant contained in the first unstretched film 7 of the innermost layer of 1. The adhering lubricant means that when the exterior material 1 for an electrical storage device obtained by lamination processing is aged in a wound state, it is formed by contact with the surface 7a of the inner sealing layer 3 in the wound state. The inner layer 3 is transferred lubricant. The adhesion amount after the transfer is preferably in the range of 0.1 μg/cm ² to 0.8 μg/cm ² . If the adhesion amount is in such a range, the formability of the exterior material 1 for electrical storage devices can be improved. Among them, the adhesion amount after the transfer is more preferably in the range of 0.1 μg/cm ² to 0.6 μg/cm ² , particularly preferably in the range of 0.15 μg/cm ² to 0.45 μg/cm ² . After molding the electrical storage device exterior material 1 by deep drawing or the like, the transfer lubricant may be removed, left alone, or allowed to disappear naturally.

The metal foil layer 4 plays a role of imparting gas barrier properties to the outer packaging material 1 to prevent intrusion of oxygen and moisture. It does not specifically limit as said metal foil layer 4, For example, aluminum foil, SUS foil (stainless steel foil), copper foil etc. are mentioned, Among them, aluminum foil and SUS foil (stainless steel foil) are used preferably. The thickness of the metal foil layer 4 is preferably 5 μm to 120 μm. By being 5 μm or more, it is possible to prevent pinholes from being generated during rolling during metal foil production, and by being 120 μm or less, it is possible to reduce stress during forming such as stretching and deep drawing, thereby improving formability. Wherein, the thickness of the metal foil layer 4 is more preferably 10 μm to 80 μm.

The metal foil layer 4 is preferably subjected to chemical conversion treatment at least on the inner surface (surface on the inner sealing layer 3 side). By performing such a chemical conversion treatment, it is possible to sufficiently prevent corrosion of the surface of the metal foil due to the contents (electrolyte solution of a battery, etc.). For example, the chemical conversion treatment is performed on the metal foil by performing the following treatment. That is, for example, the chemical conversion treatment is carried out by applying any one of the following 1) to 3) aqueous solutions on the surface of the metal foil after the degreasing treatment and then drying:

1) Contains phosphoric acid;

chromic acid; and

an aqueous solution of a mixture of at least one compound selected from the group consisting of metal salts of fluorides and non-metallic salts of fluorides;

2) Contains phosphoric acid;

at least one resin selected from the group consisting of acrylic resins, chitosan derivative resins, and phenolic resins; and

an aqueous solution of a mixture of at least one compound selected from the group consisting of chromic acid and chromium (III) salts;

3) Contains phosphoric acid;

at least one resin selected from the group consisting of acrylic resins, chitosan derivative resins, and phenolic resins;

at least one compound selected from the group consisting of chromic acid and chromium(III) salts; and

An aqueous solution of a mixture of at least one compound selected from the group consisting of metal salts of fluorides and non-metallic salts of fluorides.

The amount of chromium attached to the chemical conversion coating (per side) is preferably 0.1 mg/m ² to 50 mg/m ² , particularly preferably 2 mg/m ² to 20 mg/m ² .

The thickness of the second adhesive layer (outer adhesive layer) 5 is preferably set to 1 μm to 5 μm. Among them, the thickness of the outer adhesive layer 5 is particularly preferably set to 1 μm to 3 μm from the viewpoint of thinning and reducing the weight of the outer packaging material 1 .

The thickness of the first adhesive layer (inner adhesive layer) 6 is preferably set to 1 μm to 5 μm. Among them, the thickness of the inner adhesive layer 6 is particularly preferably set to 1 μm to 3 μm from the viewpoint of thinning and reducing the weight of the outer packaging material 1 .

By molding (deep drawing, stretching, etc.) the exterior material 1 of the present invention, an exterior case (battery case, etc.) 10 can be obtained (see FIG. 4 ). In addition, the outer packaging material 1 of this invention can also be used as it is without molding (refer FIG. 4).

FIG. 3 shows one embodiment of an electrical storage device 30 constituted using the outer packaging material 1 of the present invention. This power storage device 30 is a lithium ion secondary battery. As shown in FIGS. 3 and 4 , in the present embodiment, the exterior member 15 is composed of the exterior case 10 obtained by molding the exterior material 1 and the planar exterior material 1 . Then, in the storage recess of the exterior case 10 obtained by molding the exterior material 1 of the present invention, a substantially rectangular parallelepiped-shaped power storage device main body (electrochemical element, etc.) 31 is housed. 31, the outer packaging material 1 of the present invention that has not been molded is arranged in a manner that the inner sealing layer 3 side of the outer packaging material 1 is inward (lower), and the inner sealing layer 3 of the planar outer packaging material 1 ( The peripheral portion of the first unstretched film layer 7) and the inner sealing layer 3 (first unstretched film layer 7) of the flange portion (peripheral portion for sealing) 29 of the outer case 10 are sealed by heat sealing. The power storage device 30 (see FIGS. 3 and 4 ) of the present invention is constituted by hermetically joining and sealing. It should be noted that the inner surface of the storage recess of the exterior case 10 is the inner sealing layer 3 (first unstretched film layer 7), and the outer surface of the storage recess is the heat-resistant resin layer (outer layer) 2. (Refer to Figure 4).

In FIG. 3 , 39 is a heat-sealed portion formed by joining (welding) the peripheral edge portion of the outer packaging material 1 and the flange portion (peripheral edge portion for sealing) 29 of the outer casing 10 . It should be noted that, in the power storage device 30 described above, the tip portion of the tab connected to the power storage device main body 31 is led out to the outside of the exterior member 15 , which is not shown in the figure.

The power storage device main body 31 is not particularly limited, and examples thereof include a battery main body, a capacitor main body, and a capacitor main body.

The width of the heat-sealed portion 39 is preferably set to 0.5 mm or more. By setting it to 0.5 mm or more, reliable sealing can be performed. Wherein, the width of the heat-sealed portion 39 is preferably set at 3 mm to 15 mm.

It should be noted that, although in the above-mentioned embodiment, the exterior member 15 is composed of the exterior case 10 obtained by molding the exterior material 1 and the planar exterior material 1 (see FIGS. 3 and 4 ), it does not Such a combination is not particularly limited, and for example, the exterior member 15 may be formed of a pair of planar exterior materials 1 , or may be formed of a pair of exterior cases 10 .

Example

Next, specific examples of the present invention will be described, but the present invention is not particularly limited to these examples.

<Example 1>

On both sides of an aluminum foil 4 with a thickness of 40 μm, a chemical conversion treatment liquid containing phosphoric acid, polyacrylic acid (acrylic resin), chromium (III) salt compound, water, and alcohol is coated, and then dried at 180° C. to form Chemical conversion coating. The amount of chromium attached to each side of the chemical conversion coating was 10 mg/m ² .

Next, on one side of the aluminum foil 4 that has undergone the chemical conversion treatment, biaxially stretched nylon with a thickness of 25 μm is dry-laminated (bonded) through a two-component curing type polyurethane adhesive 5 . 6 film 2.

Next, using a T-die, the first unstretched film 7 with a thickness of 12 μm formed by containing ethylene-propylene random copolymer, 1000 ppm of erucamide, and 2000 ppm of silica particles (anti-blocking agent), containing The second unstretched film 8 having a thickness of 28 μm formed by an ethylene-propylene block copolymer and 2500 ppm of erucamide was coextruded in such a manner that two layers were sequentially laminated to obtain the above-mentioned two-layer laminated film. And the thickness that forms is the sealing film (the first unstretched film layer 7/the second unstretched film layer 8) 3 of 40 μm, then, the second unstretched film layer 8 face of this sealing film 3 is passed through two The liquid-curable maleic acid-modified polypropylene adhesive 6 is superimposed on the other side of the dry-laminated aluminum foil 4, and is sandwiched by rubber nip rollers and heated to 100°C. Dry lamination was carried out between lamination rolls and pressure-bonded, and then aged (heated) at 40° C. for 10 days to obtain an electrical storage device exterior material 1 having the configuration shown in FIG. 1 .

It should be noted that, as the two-component curing type maleic acid-modified polypropylene adhesive, 100 parts by mass of maleic acid-modified polypropylene (melting point: 80° C., acid value: 10 mgKOH/g ), 8 parts by mass of hexamethylene diisocyanate isocyanurate (NCO content: 20 mass %) as a curing agent, and a solvent were mixed to prepare an adhesive solution, and the adhesive solution was used , apply the adhesive solution on the other side surface of the aluminum foil 4 in such a way that the solid content coating amount becomes 2 g/m ² , heat and dry it, and then, with the second layer of the sealing film 3 The unstretched film layers are laminated on 8 sides.

In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.27 μg/cm ² (Table 1).

<Example 2>

On both sides of an aluminum foil 4 with a thickness of 40 μm, a chemical conversion treatment liquid containing phosphoric acid, polyacrylic acid (acrylic resin), chromium (III) salt compound, water, and alcohol is coated, and then dried at 180° C. to form Chemical conversion coating. The amount of chromium attached to each side of the chemical conversion coating was 10 mg/m ² .

Next, on one side of the aluminum foil 4 that has undergone the chemical conversion treatment, biaxially stretched nylon with a thickness of 25 μm is dry-laminated (bonded) through a two-component curing type polyurethane adhesive 5 . 6 film 2.

Next, using a T-die, the first unstretched film 7 with a thickness of 6 μm formed by containing an ethylene-propylene random copolymer, 1000 ppm of erucamide, and 2000 ppm of silica particles (anti-blocking agent), containing A second unstretched film 8 with a thickness of 28 μm formed from an ethylene-propylene block copolymer and 2500 ppm of erucamide, containing ethylene-propylene random copolymer, 1000 ppm of erucamide and 2000 ppm of silica particles ( anti-blocking agent) and the first unstretched film 9 with a thickness of 6 μm was co-extruded in a manner of sequentially laminating three layers, thereby obtaining a sealing film with a thickness of 40 μm formed by laminating the above three layers (the first unstretched film layer 7/the second unstretched film layer 8/the first unstretched film layer 9) 3, then, the first unstretched film layer 9 surface on one side of the sealing film 3 The surface on the other side of the dry-laminated aluminum foil 4 is superimposed on the other side of the dry-laminated aluminum foil 4 through the two-component curing type maleic acid-modified polypropylene adhesive 6, and is heated to Dry lamination was carried out between lamination rolls at 100°C with pressure, and then aged (heated) at 40°C for 10 days to obtain the outer packaging material for an electrical storage device with the configuration shown in Fig. 2 1.

It should be noted that, as the two-component curing type maleic acid-modified polypropylene adhesive, 100 parts by mass of maleic acid-modified polypropylene (melting point: 80° C., acid value: 10 mgKOH/g ), 8 parts by mass of hexamethylene diisocyanate isocyanurate (NCO content: 20 mass %) as a curing agent, and a solvent were mixed to prepare an adhesive solution, and the adhesive solution was used , apply the adhesive solution on the other side surface of the aluminum foil 4 in such a manner that the coating amount of the solid component becomes 2 g/m ² , heat and dry it, and then, with one side of the sealing film 3 The first unstretched film layer 9 faces are laminated.

In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.25 μg/cm ² (Table 1).

<Example 3>

Except that the concentration of erucamide in the second unstretched film layer 8 before lamination was set to 1000 ppm, the same procedure as in Example 2 was carried out to obtain an electrical storage device having the configuration shown in FIG. 2 Use outer packing material 1. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.20 μg/cm ² (Table 1).

<Example 4>

Except that the content concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 500 ppm, it was carried out in the same manner as in Example 2 to obtain a battery having the configuration shown in FIG. 2 . Outer packaging materials for electrical devices 1. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.15 μg/cm ² (Table 1).

<Example 5>

The content concentration of erucamide in the second unstretched film layer 8 before lamination was set to 1000 ppm, and the content concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 1000 ppm. Except having set it as 2000 ppm, it carried out similarly to Example 2, and obtained the exterior material 1 for electrical storage devices of the structure shown in FIG. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.35 μg/cm ² (Table 1).

<Example 6>

In the first unstretched film layer 7, 9 and the second unstretched film layer 8, as a lubricant, use behenamide instead of erucamide, except that, operate in the same way as in Example 2, and obtain the The exterior material 1 for an electrical storage device having the configuration shown in 2. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.19 μg/cm ² (Table 1).

<Example 7>

In the first unstretched film layer 7,9 and the second unstretched film layer 8, as a lubricant, use oleic acid amide instead of erucic acid amide, except that, operate in the same way as in Example 2, and obtain Fig. The exterior material 1 for an electrical storage device having the configuration shown in 2. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.50 μg/cm ² (Table 1).

<Embodiment 8>

In the first unstretched film layer 7, 9 and the second unstretched film layer 8, as a lubricant, stearic acid amide is used instead of erucamide, except that it is performed in the same manner as in Example 2 to obtain the The exterior material 1 for an electrical storage device having the configuration shown in 2. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.30 μg/cm ² (Table 1).

<Example 9>

Except that the content concentration of erucamide in the second unstretched film layer 8 before lamination was set to 4500 ppm, it was carried out in the same manner as in Example 2, and an electrical storage device having the configuration shown in FIG. 2 was obtained. Use outer packing material 1. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.10 μg/cm ² (Table 1).

<Comparative example 1>

Except having set the content concentration of the erucamide in the 2nd unstretched film layer 8 before lamination to 300 ppm, it carried out similarly to Example 1, and obtained the exterior material for electrical storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.07 μg/cm ² (Table 1).

<Comparative example 2>

Except having set the content concentration of the erucamide in the 2nd unstretched film layer 8 before lamination to 300 ppm, it carried out similarly to Example 2, and obtained the exterior material for electrical storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.08 μg/cm ² (Table 1).

<Comparative example 3>

The content concentration of erucamide in the second unstretched film layer 8 before lamination was set to 8000 ppm, and the content concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 8000 ppm. Except having set it as 2000ppm, it carried out similarly to Example 2, and obtained the outer packaging material for electrical storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 1.31 μg/cm ² (Table 1).

<Comparative example 4>

The content concentration of erucamide in the second unstretched film layer 8 before lamination was set to 1500 ppm, and the content concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 1500 ppm. Except having set it as 8000ppm, it carried out similarly to Example 2, and obtained the outer packaging material for electrical storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 1.05 μg/cm ² (Table 1).

<Comparative example 5>

The content concentration of erucamide in the second unstretched film layer 8 before lamination was set to 1500 ppm, and the content concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 1500 ppm. Except having set it as 100 ppm, it carried out similarly to Example 2, and obtained the exterior material for electrical storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.06 μg/cm ² (Table 1).

<Comparative example 6>

The content concentration of erucamide in the second unstretched film layer 8 before lamination was set to 100 ppm, and the content concentration of erucamide in the first unstretched film layer 7 before lamination was set to 100 ppm. Except for 250 ppm, it carried out similarly to Example 1, and obtained the outer packaging material for electric storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.02 μg/cm ² (Table 1).

<Comparative example 7>

The concentration of erucamide in the second unstretched film layer 8 before lamination was set to 100 ppm, and the concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 100 ppm. Except having set it as 250 ppm, it carried out similarly to Example 2, and obtained the outer packaging material for electrical storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 0.02 μg/cm ² (Table 1).

<Comparative example 8>

The content concentration of erucamide in the second unstretched film layer 8 before lamination was set to 21000 ppm, and the content concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 21000 ppm. Except having set it as 3500ppm, it carried out similarly to Example 2, and obtained the exterior material for electrical storage devices. In the obtained exterior material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the exterior material was 3.20 μg/cm ² (Table 1).

<Comparative example 9>

The concentration of erucamide in the second unstretched film layer 8 before lamination was set to 100 ppm, and the concentration of erucamide in the first unstretched film layers 7 and 9 before lamination was set to 100 ppm. Except having set it as 3500ppm, it carried out similarly to Example 2, and obtained the exterior material for electrical storage devices. In the obtained outer packaging material 1 for an electrical storage device, the amount of lubricant present on the surface 7a of the innermost layer (first unstretched film layer 7) of the outer packaging material was 0.05 μg/cm ² (Table 1)

Each of the exterior materials for electrical storage devices obtained as described above (completed with aging treatment) was evaluated based on the following evaluation method. The results are shown in Table 1. In addition, the dynamic friction coefficient shown in Table 1 is a dynamic friction coefficient measured by JISK7125-1995 with respect to the surface 7a of the innermost layer of each electrical storage device exterior material (aging process completed).

<Evaluation method for the amount of lubricant present on the surface of the innermost layer of the outer packaging material>

Two rectangular test pieces with a length of 100 mm x a width of 100 mm were cut out from each electrical storage device outer packaging material, and then these two test pieces were stacked, and the peripheral parts of the sealing layers of the two were heat-sealed to each other. Heat sealing is performed at a temperature of 200° C. to form a bag body. Inject 1 mL of acetone into the inner space of the bag using a syringe, leave the surface of the innermost layer 7 of the sealing layer in contact with the acetone for 3 minutes, and then take out the acetone in the bag. The amount of lubricant contained in the extracted liquid was measured and analyzed by gas chromatography, thereby obtaining the amount of lubricant (μg/cm ² ) present on the innermost surface of the packaging material. That is, the amount of lubricant per 1 cm ² of the surface of the innermost layer was obtained.

<Moldability Evaluation Method>

Use a straight mold with unlimited molding depth to perform deep drawing of the outer packaging material in one stage according to the following molding conditions, and perform moldability for each molding depth (9mm, 8mm, 7mm, 6mm, 5mm, 4mm, 3mm, 2mm) For evaluation, the maximum molding depth (mm) at which good molding can be performed without any pinholes at the corners was investigated. The case where the maximum molding depth was 5 mm or more was judged as "○", the case where the maximum molding depth was 2 mm or more and less than 5 mm was judged as "△", and the case where the maximum molding depth was less than 2 mm was judged as "×". The results are shown in Table 1. It should be noted that the presence or absence of pinholes was investigated by visually observing the presence or absence of transmitted light passing through the pinholes.

(molding conditions)

Forming die... Punch: 33.3mm×53.9mm, Die: 80mm×120mm, Corner R: 2mm, Punch R: 1.3mm, Die R: 1mm

Anti-wrinkle pressure...gauge pressure: 0.475MPa, real pressure (calculated value): 0.7MPa

Material...SC (carbon steel), only the punch R is chrome-plated.

<How to evaluate the presence or absence of white powder>

A rectangular test piece with a length of 600 mm x a width of 100 mm was cut out from each storage material for an electrical storage device, and the obtained test piece was mounted with the inner side sealing layer 3 (i.e., the innermost surface 7a) as the upper side. Placed on the test stand, and placed on the upper surface of the test piece, a SUS hammer (mass 1.3 kg, ground surface size 55 mm x 50 mm) wrapped with black cloth (Waste) with a black surface, The hammer was pulled in a horizontal direction parallel to the upper surface of the test piece at a pulling speed of 4 cm/sec, thereby moving the hammer over a length of 400 mm while being in contact with the upper surface of the test piece. The cloth (black) on the contact surface of the hammer after being pulled was visually observed, and the case where white powder was remarkably generated on the surface of the cloth (black) was evaluated as "x", and the case where white dust was generated to a certain degree (medium degree) was evaluated as "△" and the case where almost no white powder was observed or no white powder was observed were evaluated as "◯". In addition, as the said black cloth, the TRUSCO company make "static destaticizing thin cloth S SD2525 3100" was used.

<Comprehensive Judgment>

When the evaluation of formability is "○" and the evaluation of the presence or absence of white powder is also "○", it is judged as "○" in the comprehensive judgment; at least one of the evaluation of moldability and the evaluation of the presence or absence of white powder is "×" In the case of , it was judged as "×" in the comprehensive judgment.

As can be seen from Table 1, the outer packaging materials for electrical storage devices of the present invention of Examples 1 to 9 constituted using the sealing film of the present invention have excellent moldability, and white powder is less likely to be exposed on the surface of the outer packaging materials.

On the other hand, in Comparative Examples 1, 2, 5 to 7, and 9 that deviate from the prescribed range of the present invention, the moldability of the outer packaging material was not good, and in Comparative Examples 3, 4, and 8 that deviated from the prescribed range of the present invention, the outer packaging materials were poor. White powder was remarkably generated on the surface of the packaging material.

Industrial availability

The outer packaging material for electrical storage devices produced using the sealing film according to the present invention and the outer packaging material for electrical storage devices according to the present invention can be used as outer packaging materials for various electrical storage devices. As specific examples, for example:

Lithium secondary batteries (lithium ion batteries, lithium polymer batteries, etc.) and other power storage devices;

Lithium-ion capacitors;

· Electric double layer capacitors; etc.

In addition, in addition to the power storage devices exemplified above, the power storage device according to the present invention also includes an all-solid-state battery.

This application claims the priority of Japanese Patent Application Japanese Patent Application No. 2016-115176 for which it applied on June 9, 2016, and the disclosure content directly constitutes a part of this application.

The terms and descriptions used here are for explaining the embodiments related to the present invention, and the present invention is not limited thereto. The present invention also allows any design changes within the scope of the claims as long as they do not exceed the gist thereof.

Claims (15)

1. the housing material diaphragm seal of electrical storage device, it is characterised in that by comprising the first non-stretched film layer and being laminated at institute More than 2 layers of lamilate for stating the second non-stretched film layer in the face of the side of the first non-stretched film layer is formed,

The first non-stretched film layer forms the innermost layer of housing material,

The first non-stretched film layer contains random copolymer and lubricant, the random copolymer contain propylene and except propylene with Other outer copolymer compositions as copolymer composition,

The second non-stretched film layer contains block copolymer and lubricant, the block copolymer contain propylene and except propylene with Other outer copolymer compositions as copolymer composition,

Lubricant in the first non-stretched film layer is 200ppm~3000ppm containing concentration, second unstretching film Lubricant in layer containing concentration is 500ppm~5000ppm.

2. the housing material diaphragm seal of electrical storage device, it is characterised in that by comprising the second non-stretched film layer, be laminated at it is described The first non-stretched film layer in the face of the side of the second non-stretched film layer and the opposite side for being laminated at the described second non-stretched film layer More than 3 layers of lamilate of the first non-stretched film layer in face is formed,

Described the first of certain side being laminated at respectively in the first non-stretched film layer of the both sides of the described second non-stretched film layer is not Stretch film layers form the innermost layer of housing material,

The first non-stretched film layer contains random copolymer and lubricant, the random copolymer contain propylene and except propylene with Other outer copolymer compositions as copolymer composition,

The second non-stretched film layer contains block copolymer and lubricant, the block copolymer contain propylene and except propylene with Other outer copolymer compositions as copolymer composition,

Lubricant in the first non-stretched film layer is 200ppm~3000ppm containing concentration, second unstretching film Lubricant in layer containing concentration is 500ppm~5000ppm.

3. the housing material diaphragm seal of electrical storage device as claimed in claim 1 or 2, wherein, second unstretching film The lubricant that lubricant in layer contains in the described first non-stretched film layer that concentration is the innermost layer to form housing material contains There are 0.5 times~5 times of concentration.

4. the housing material diaphragm seal of electrical storage device as claimed in claim 1 or 2, wherein, second unstretching film The lubricant that lubricant in layer contains in the described first non-stretched film layer that concentration is the innermost layer to form housing material contains There are 1.0 times~3.0 times of concentration.

5. the housing material diaphragm seal of electrical storage device as claimed in claim 1 or 2, wherein, the lubricant be selected from At least one of the group being made up of unsaturated fatty acid amide and unrighted acid acid amides lubricant.

6. the housing material diaphragm seal of electrical storage device as claimed in claim 1 or 2, wherein, form the innermost layer Lubricant in first non-stretched film layer is 800ppm~1200ppm containing concentration, the profit in the second non-stretched film layer Lubrication prescription is 800ppm~2700ppm containing concentration.

7. electrical storage device housing material, it is characterised in that comprising by diaphragm seal according to any one of claims 1 to 6 The inner seal layer of formation and be laminated at the inner seal layer a surface side metal foil layer.

8. electrical storage device housing material, it is characterised in that comprising the heat-resistant resin layer as outer layer, by claim Inner seal layer that diaphragm seal any one of 1~6 is formed and it is configured at the heat-resistant resin layer and the inner side is close Metal foil layer between this two layers of sealing.

9. electrical storage device housing material as claimed in claim 7 or 8, wherein, it is present in form housing material most The amounts of lubrication on the surface of the described first non-stretched film layer of internal layer is 0.1 μ g/cm²~1.0 μ g/cm²Scope.

10. electrical storage device housing material as claimed in claim 7 or 8, wherein, form the innermost layer of housing material The coefficient of kinetic friction on the surface of the first non-stretched film layer is 0.10~0.50 scope.

11. the manufacture method of electrical storage device housing material, it is characterised in that including：

Prepare the process of lamilate, the lamilate is will be according to any one of claims 1 to 6 close via first bonding agents Sealer and metal foil carry out laminated form；With

Curing step, the lamilate is heated, so as to obtain electrical storage device housing material.

12. the manufacture method of electrical storage device housing material as claimed in claim 11, wherein, the first bonding agents are Heat-curable adhesive.

13. the manufacture method of electrical storage device housing material, it is characterised in that including：

Prepare the process of lamilate, the composition of the lamilate is to have in the face of the side of metal foil via second bonding agents are laminated Heat-resistant resin film and the metal foil opposite side face via first bonding agents in laminated requirement 1~6 of having the right appoint Diaphragm seal described in one；With

Curing step, the lamilate is heated, so as to obtain electrical storage device housing material.

14. the manufacture method of electrical storage device housing material as claimed in claim 13, wherein, the first bonding agents are Heat-curable adhesive, the second bonding agents are heat-curable adhesive.

15. the manufacture method of the electrical storage device housing material as any one of claim 11~14, wherein, in shape The described first non-stretched film layer of the innermost layer of the electrical storage device housing material into obtained from being heated Surface existing for amounts of lubrication be 0.1 μ g/cm²~1.0 μ g/cm²Scope.