JP2018156849A - Sealant film for exterior material of power storage device, exterior material for power storage device, and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealant film for a power storage device exterior material, which is superior in moldability and hard to cause white powder to appear on its surface, and by which a satisfactory lamination strength and an adequate seal strength can be achieved.SOLUTION: A sealant film for a power storage device exterior material is composed of a laminate having two or more layers including of a first non-stretched film layer 7 disposed on a side closest to metal foil, and a second non-stretched film layer 8 laminated on one face of the first non-stretched film layer. The first non-stretched film layer 7 includes a random copolymer including propylene as a copolymerization component, and another copolymerization component other than the propylene, and no lubricant or a lubricant of over 0 ppm up to 250 ppm. The second non-stretched film layer 8 includes a propylene-based polymer and a lubricant; the content of the lubricant is 500-5000 ppm in the second non-stretched film layer 8.SELECTED DRAWING: Figure 1

Description

  The present invention is a battery and capacitor used for portable devices such as smartphones and tablets, a hybrid vehicle, an electric vehicle, wind power generation, solar power generation, and an exterior of a power storage device such as a battery and capacitor used for power storage for night electricity. The present invention relates to a sealant film used for constituting a material, and a method for producing an exterior material for an electricity storage device using the sealant film.

  In recent years, as mobile electrical devices such as smartphones and tablet terminals have become thinner and lighter, power storage devices such as lithium-ion secondary batteries, lithium-polymer secondary batteries, lithium-ion capacitors, and electric double-layer capacitors that are installed in these devices have been reduced. As the exterior material, a laminate composed of a heat resistant resin layer / adhesive layer / metal foil layer / adhesive layer / thermoplastic resin layer (inner sealant layer) is used instead of a conventional metal can. In addition, a power source for an electric vehicle, a large-scale power source for power storage, a capacitor, and the like are increasingly covered with a laminate (exterior material) having the above-described configuration. The laminated body is formed into a three-dimensional shape such as a substantially rectangular parallelepiped shape by performing overhang molding or deep drawing. By forming into such a three-dimensional shape, an accommodation space for accommodating the electricity storage device main body can be secured.

  In order to form such a three-dimensional shape in a good state without pinholes or breakage, it is required to improve the slipperiness of the surface of the inner sealant layer. In order to improve the slipperiness of the surface of the inner sealant layer and ensure good moldability, an exterior resin film, a first adhesive layer, a chemical conversion treated aluminum foil, a second adhesive layer, and a sealant film are sequentially laminated. The sealant film is made of a random copolymer of propylene and α-olefin having an α-olefin content of 2 to 10% by weight, and contains 1000 to 5000 ppm of a lubricant. A laminated material for a secondary battery container has been proposed (see Patent Document 1).

JP 2003-288865 A

  However, in the above prior art, it is difficult to control the amount of lubricant deposited on the innermost surface of the exterior material (the inner surface of the inner sealant layer) depending on the heating retention time and storage period in the production process of the exterior material (laminate material). Although the slipperiness is good, the lubricant is excessively deposited on the surface, so that the lubricant adheres to the molding surface of the molding die during molding of the exterior material, and white powder (white powder by the lubricant) is generated. When such white powder is deposited and deposited on the molding surface, it becomes difficult to perform good molding, so it is necessary to clean and remove the white powder every time white powder is deposited and deposited. There has been a problem that the productivity of the exterior material is reduced by performing the cleaning removal.

  In addition, a large amount of lubricant bleeds on the surface of the inner sealant layer on the metal foil side, which reduces the laminate strength (laminate strength between the metal foil and the inner sealant layer), and between the metal foil and the inner sealant layer. There was also a problem that peeling was likely to occur.

  Of course, if the amount of lubricant added (lubricant content) is reduced, it is possible to suppress adhesion and deposition of white powder and prevent a decrease in laminate strength. In this case, however, the amount of surface lubricant deposited is insufficient. This causes the problem that the moldability deteriorates. Thus, conventionally, it has been difficult to achieve both “excellent moldability” and “suppression of white powder expression on the surface of the exterior material and securing sufficient laminate strength”.

  The present invention has been made in view of such a technical background, and is excellent in moldability, difficult to expose white powder on the surface, and capable of obtaining sufficient laminate strength and sufficient seal strength. It aims at providing the sealant film for materials, the exterior material for electrical storage devices, and its manufacturing method.

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

[1] A sealant film comprising a laminate of two or more layers including a first unstretched film layer and a second unstretched film layer laminated on one surface of the first unstretched film layer,
The first unstretched film layer is a layer disposed on the most metal foil side in the sealant film,
The first unstretched film layer contains a random copolymer containing propylene and other copolymer components excluding propylene as a copolymer component,
The first unstretched film layer has a configuration that does not contain a lubricant, or a configuration that contains a lubricant in excess of 0 ppm to 250 ppm,
The second unstretched film layer contains a propylene polymer and a lubricant,
A sealant film for an exterior material for an electricity storage device, wherein the content concentration of the lubricant in the second unstretched film layer is 500 ppm to 5000 ppm.

  [2] The third unstretched film layer further includes a third unstretched film layer laminated on a surface opposite to the side on which the first unstretched film layer is laminated in the second unstretched film layer. Contains a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component, and a lubricant, and the content concentration of the lubricant in the third unstretched film layer is 200 ppm to 3000 ppm. 2. A sealant film for an exterior material for an electricity storage device according to item 1 above.

  [3] For the exterior material of the electricity storage device according to the above item 2, wherein the lubricant-containing concentration in the second unstretched film layer is 1.0 to 5.0 times the lubricant-containing concentration in the third unstretched film layer. Sealant film.

[4] The amount of lubricant present on the surface of the second unstretched film layer includes an inner sealant layer made of the sealant film according to the preceding item 1 and a metal foil layer laminated on one side of the inner sealant layer. exterior material for a power storage device which is a range of ^{0.1μg / cm 2 ~1.0μg / cm 2} .

[5] A lubricant present on the surface of the third unstretched film layer, comprising an inner sealant layer comprising the sealant film according to the above item 2 or 3, and a metal foil layer laminated on one side of the inner sealant layer. exterior material for a power storage device that amount is equal to or is in the range of ^{0.1μg / cm 2 ~1.0μg / cm 2} .

[6] A surface of the second unstretched film layer, including a heat-resistant resin layer as an outer layer, an inner sealant layer made of the sealant film described in the preceding item 1, and a metal foil layer disposed between the two layers. exterior material for a power storage device, wherein the lubricant amount existing in the range of 0.1μg / cm ² ~1.0μg / cm ² in.

[7] A third unstretched film layer comprising a heat-resistant resin layer as an outer layer, an inner sealant layer made of the sealant film described in the preceding item 2 or 3, and a metal foil layer disposed between these layers. exterior material for a power storage device that amount lubricant present on the surface of and wherein in the range of ^{0.1μg / cm 2 ~1.0μg / cm 2} .

  [8] An exterior case for an electricity storage device comprising the molded body of the exterior material according to any one of 4 to 7 above.

[9] A step of preparing a laminate in which the sealant film according to any one of the preceding items 1 to 3 and a metal foil are laminated via a first adhesive;
An aging step of obtaining a power storage device exterior material by heat-treating the laminate, and a method for producing a power storage device exterior material.

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

[11] The heat-resistant resin film is laminated on one surface of the metal foil via a second adhesive, and any one of items 1 to 3 above on the other surface of the metal foil via a first adhesive. A step of preparing a laminate having a structure in which the sealant film described in 1 is laminated;
An aging step of obtaining a power storage device exterior material by heat-treating the laminate, and a method for producing a power storage device exterior material.

  [12] The method for manufacturing an exterior material for an electricity storage device according to [11], wherein the first adhesive is a thermosetting adhesive and the second adhesive is a thermosetting adhesive.

[13] any one of items 9-12 in the range lubricant amount existing on the outermost layer of the surface of 0.1μg / cm ² ~1.0μg / cm ² of the heat treatment the electric storage device for exterior materials obtained by The manufacturing method of the exterior | packing material for electrical storage devices of Claim 1.

  In the inventions of [1] and [2], it is possible to suppress a decrease in the amount of lubricant existing (precipitating) on the inner surface (surface of the inner sealant layer) of the exterior material after the aging treatment, which is good at the time of molding. In addition to ensuring slipperiness and excellent moldability, it is difficult for white powder to appear on the inner surface of the exterior material (the surface of the innermost layer of the inner sealant layer), and sufficient sealing strength is obtained. Further, since the amount of lubricant present on the surface 7a of the first unstretched film layer on the metal foil side in the inner sealant layer of the exterior material after the aging treatment is small, sufficient laminate strength (metal foil and inner sealant layer and Can be ensured. In addition, the amount of lubricant present on the surface of the exterior material after the aging treatment (the surface of the innermost layer of the inner sealant layer) does not change even when subjected to a heat history during transportation or storage, so excellent moldability is stable. Thus, it is possible to provide the exterior material provided.

In the invention of [3], the lubricant-containing concentration in the second unstretched film layer is 1.0 to 5.0 times the lubricant-containing concentration in the third unstretched film layer forming the innermost layer of the exterior material. When the aging treatment is performed, the interface due to the lubricant concentration gradient from the innermost third unstretched film layer 9 to the second unstretched film layer 8 (both films) The concentration of the lubricant to the interface between the layers 8 and 9 can be suppressed, and the lubricant of the lubricant from the second unstretched film layer 8 to the innermost third unstretched film layer 9 can be reduced by 5.0 times or less. Lubricant present on the surface 9a of the third unstretched film layer that can suppress intensive movement to the interface (interface between both film layers 8 and 9) due to the concentration gradient and forms the innermost layer of the exterior material after the aging treatment range the amount of 0.1μg / cm ² ~1.0μg / cm ² It is possible to control. Thereby, moldability can be further improved.

  In the inventions of [4], [5], [6] and [7], the exterior for an electricity storage device is excellent in moldability, difficult to expose white powder on the surface, and having sufficient laminate strength and sufficient seal strength. Can provide material.

  Further, in the inventions [6] and [7], since the heat-resistant resin layer is further provided as the outer layer, the insulation on the side opposite to the inner sealant layer in the metal foil layer can be sufficiently secured, and the electricity storage device The physical strength and impact resistance of the exterior packaging material can be improved.

  In the invention of [8], the battery is formed with good molding, white powder is difficult to be exposed on the surface of the outer case (the innermost surface of the inner sealant layer), and sufficient laminate strength and sufficient seal strength can be obtained. A device outer case can be provided.

  In the inventions [9] to [12], it is possible to manufacture an exterior device for an electricity storage device that is excellent in moldability, is difficult to expose white powder on the surface, and has sufficient laminate strength and sufficient seal strength.

  Further, in the inventions of [11] and [12], since the heat-resistant resin layer is further provided as the outer layer, the insulation on the side opposite to the inner sealant layer in the metal foil layer can be sufficiently secured, and the exterior material It is possible to improve the physical strength and impact resistance.

[13] In the invention, since the range lubricant amount existing on the outermost layer of the surface of 0.1μg / cm ² ~1.0μg / cm ² of the outer package, thereby demonstrating a good sliding property with time of molding, In addition, it is possible to manufacture an exterior device for an electricity storage device that can secure good moldability and can further prevent the white powder from being exposed. The amount of lubricant (0.1 μg / cm ^{2 to} 1.0 μg / cm ² ) present on the surface of the innermost layer of the obtained electricity storage device exterior material varies even if it receives a heat history during transportation or storage. Therefore, an exterior material for an electricity storage device that stably has excellent moldability can be provided.

It is sectional drawing which shows one Embodiment of the exterior material for electrical storage devices which concerns on this invention. It is sectional drawing which shows other embodiment of the exterior material for electrical storage devices which concerns on this invention. It is sectional drawing which shows one Embodiment of the electrical storage device which concerns on this invention. It is a perspective view shown in the separated state before heat-sealing the exterior material (planar thing) which comprises the electrical storage device of FIG. 3, the electrical storage device main-body part, and an exterior case (molded object shape | molded by the solid shape).

  One embodiment of the sealant film 3 for an exterior material for an electricity storage device according to the first invention is shown in FIG. The sealant film 3 is composed of a laminate of two or more layers including a first unstretched film layer 7 and a second unstretched film layer 8 laminated on one surface of the first unstretched film layer 7. The first unstretched film layer 7 is a layer disposed on the most side of the metal foil 4 in the sealant film 3, and the first unstretched film layer is a copolymer component other than propylene and propylene. A random copolymer containing a polymerization component is contained, and the first non-stretched film layer 7 has a constitution that does not contain a lubricant or a constitution that contains a lubricant, and the second non-stretched film layer 8 has a propylene-based composition. Contains a polymer and a lubricant.

  Moreover, one Embodiment of the sealant film for exterior materials of an electrical storage device based on 2nd invention is shown in FIG. The sealant film 3 includes a second unstretched film layer 8, a first unstretched film layer 7 laminated on one surface of the second unstretched film layer 8, and the other of the second unstretched film layer 8. And a third non-stretched film layer 9 laminated on the surface, and the first non-stretched film layer 7 is disposed closest to the metal foil 4 in the sealant film 3. The first unstretched film layer 7 includes a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component, and the first unstretched film layer 7 includes a lubricant. The second unstretched film layer 8 contains a propylene-based polymer and a lubricant, and the third unstretched film layer 9 is a copolymer component. As propylene and Containing a random copolymer containing other copolymerizable components except propylene, and a lubricant, a.

  The random copolymer constituting the first unstretched film layer 7 and the third unstretched film layer 9 includes “propylene” and “another copolymer component excluding propylene” as copolymerization components. It is a coalescence. With respect to the random copolymer, the “other copolymerization component excluding propylene” is not particularly limited. For example, ethylene, 1-butene, 1-hexene, 1-pentene, 4methyl-1 -In addition to olefin components such as pentene, butadiene and the like can be mentioned.

  The propylene polymer constituting the second unstretched film layer 8 is a polymer containing at least propylene as a polymerization component. The propylene-based polymer is not particularly limited, and examples thereof include homopolypropylene, and a block copolymer containing “propylene” and “another copolymer component excluding propylene” as a copolymer component. It is done. Among these, as the propylene polymer, it is preferable to use at least one resin selected from the group consisting of homopolypropylene and the block copolymer.

  With respect to the block copolymer, the “other copolymerization component excluding propylene” is not particularly limited. For example, ethylene, 1-butene, 1-hexene, 1-pentene, 4methyl-1 -In addition to olefin components such as pentene, butadiene and the like can be mentioned.

  The second unstretched film layer 8 preferably includes the propylene polymer, an elastomer component, and the lubricant. Among these, it is more preferable that the elastomer component is added to the propylene polymer to exhibit a microphase separated morphology (microstructure). That is, the propylene-based polymer is preferably an elastomer-modified propylene-based polymer exhibiting a sea-island structure in which an elastomer component is phase-separated into islands in the sea, and in this case, the whitening phenomenon can be made less likely to occur. The insulation after sealing can be further improved. The elastomer component is not particularly limited, and examples thereof include EPR (ethylene propylene rubber), propylene-butene elastomer, propylene-butene-ethylene elastomer, EPDM (ethylene-propylene-diene rubber), and the like. It is preferable to use EPR (ethylene propylene rubber) as the elastomer component.

  And the sealant film 3 which concerns on 1st invention is a structure in which the said 1st unstretched film layer 7 does not contain a lubricant, or is a structure which contains a lubricant more than 0 ppm and 250 ppm or less, and said 2nd unstretched film It is important that the concentration of the lubricant in the film layer is set to 500 ppm to 5000 ppm. By satisfying such conditions, the lubricant present in the second unstretched film layer 8 moves into the first unstretched film layer 7 when an aging treatment for curing the adhesive is performed. Therefore, the amount of lubricant deposited on the surface 8a of the innermost layer (second unstretched film layer) of the outer packaging material 1 can be secured, and excellent slipperiness can be secured during molding of the outer packaging material. Is obtained, white powder is difficult to be exposed on the surface 8a of the innermost layer (second unstretched film layer 8), and sufficient laminate strength and sufficient seal strength can be secured. When the content concentration of the lubricant in the first unstretched film layer 7 exceeds 250 ppm, the amount of lubricant present on the surface 7a on the metal foil layer 4 side in the first unstretched film layer 7 increases, and sufficient laminate strength (metal foil) And the inner sealant layer). Moreover, if the content concentration of the lubricant in the second unstretched film layer 8 is less than 500 ppm, the amount of lubricant present on the surface 8a of the innermost layer of the exterior material 1 after the aging treatment for curing the adhesive is sufficient. When it exceeds 5000 ppm, the lubricant moves from the second unstretched film layer 8 to the first unstretched film layer 7 after the aging treatment for curing the adhesive. The amount of lubricant present on the surface 7a on the metal foil layer 4 side in the first unstretched film layer 7 increases, and sufficient laminate strength (laminate strength between the metal foil and the inner sealant layer) cannot be secured. White powder is prominently generated on the surface 8a of the inner layer (second unstretched film layer 8).

  Among them, in the sealant film 3 according to the first invention, the first unstretched film layer 7 is preferably configured so as not to contain a lubricant, or preferably contains a lubricant in excess of 0 ppm to 150 ppm. Furthermore, in the sealant film 3 according to the first invention, the first unstretched film layer 7 more preferably contains 10 ppm to 90 ppm of lubricant, particularly preferably 20 ppm to 60 ppm of lubricant. The second unstretched film layer 8 preferably contains 700 to 4500 ppm of lubricant, more preferably contains 800 to 4000 ppm of lubricant, and particularly preferably contains 1000 to 2700 ppm of lubricant.

  Further, in the case of adopting a configuration in which the third unstretched film layer is further provided (second invention), the first unstretched film layer 7 is a configuration not containing a lubricant, or the lubricant exceeds 0 ppm. Containing 250 ppm or less, the concentration of the lubricant in the second unstretched film layer 8 is set to 500 ppm to 5000 ppm, and the concentration of the lubricant in the third unstretched film layer 9 is set to 200 ppm to 3000 ppm is important.

  By satisfying such conditions, when the aging treatment for curing the adhesive is performed, the lubricant present in the third unstretched film layer 9 is converted into the second unstretched film layer 8 and the first Since movement into the unstretched film layer 7 can be suppressed, the amount of lubricant deposited on the surface 9a of the innermost layer (third unstretched film layer) of the exterior material 1 can be ensured, and good sliding properties can be achieved during molding of the exterior material. Can be secured, and excellent moldability can be obtained, white powder is difficult to be exposed on the surface 9a of the innermost layer (third unstretched film layer 9), and sufficient laminate strength and sufficient seal strength can be secured. . When the content concentration of the lubricant in the first unstretched film layer 7 exceeds 250 ppm, the amount of lubricant present on the surface 7a on the metal foil layer 4 side in the first unstretched film layer 7 increases, and sufficient laminate strength (metal The laminate strength between the foil and the inner sealant layer cannot be secured. Moreover, when the content concentration of the lubricant in the second unstretched film layer 8 is less than 500 ppm, the innermost third unstretched film layer 9 to the second unstretched film layer are subjected to aging treatment for curing the adhesive. The amount of lubricant present on the innermost surface 9a is not sufficient, the slipping property at the time of molding is deteriorated, and when it exceeds 5000 ppm, an aging treatment for curing the adhesive was performed. In this case, the lubricant easily moves from the second unstretched film layer 8 to the first unstretched film layer 7, and the amount of lubricant present on the surface 7 a on the metal foil layer 4 side in the first unstretched film layer 7 is increased. High laminate strength (lamination strength between the metal foil and the inner sealant layer) cannot be secured. Moreover, when the content concentration of the lubricant in the third unstretched film layer 7 is less than 200 ppm, the amount of the lubricant present on the surface 9a of the innermost layer becomes insufficient after performing the aging treatment for curing the adhesive, and excellent molding. If it exceeds 3000 ppm, white powder will be noticeably generated on the surface 9a of the innermost layer after the aging treatment for curing the adhesive, and it is necessary to clean and remove the white powder. This causes a problem that productivity decreases.

  Among these, in the sealant film 3 according to the second invention, the first unstretched film layer 7 preferably does not contain a lubricant, or preferably contains a lubricant exceeding 0 ppm and not more than 150 ppm. Furthermore, in the sealant film 3 according to the second invention, the first unstretched film layer 7 more preferably contains 10 ppm to 90 ppm of lubricant, and particularly preferably contains 20 ppm to 60 ppm of lubricant. Moreover, in the sealant film 3 according to the second invention, the second unstretched film layer 8 preferably contains 700 ppm to 4500 ppm of a lubricant, more preferably contains 800 ppm to 4000 ppm of a lubricant, and more preferably 1000 ppm to It is particularly preferable to contain 2700 ppm. Moreover, in the sealant film 3 according to the second invention, the third unstretched film layer 9 preferably contains 300 ppm to 2700 ppm of a lubricant, more preferably contains 500 ppm to 2000 ppm of a lubricant, and among them, the lubricant is 800 ppm to 800 ppm. It is particularly preferable to contain 1200 ppm.

In the sealant film 3 according to the second invention, the lubricant-containing concentration in the second unstretched film layer 8 is 1.0 to 5.0 times the lubricant-containing concentration in the third unstretched film layer 9. preferable. During the aging treatment, an interface of the lubricant concentration gradient from the third unstretched film layer 9 of the innermost layer to the second unstretched film layer 8 due to being 1.0 times or more (of both film layers 8 and 9). The concentrated movement to the interface) can be suppressed, and the interface due to the lubricant concentration gradient of the lubricant from the second unstretched film layer 8 to the innermost third unstretched film layer 9 by being 5.0 times or less. The amount of lubricant present on the surface 9a of the third unstretched film layer that forms the innermost layer of the exterior material after the aging treatment can be reduced to 0.1 μg. / Cm ^{2 to} 1.0 μg / cm ² can be controlled, and the moldability can be further improved. Among them, the lubricant-containing concentration in the second unstretched film layer 8 is more preferably 1.0 to 4.5 times the lubricant-containing concentration in the third unstretched film layer 9, and more preferably 1.0. It is particularly preferable that the ratio is double to 4.0 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, and aromatic bisamides. Can be mentioned.

  The saturated fatty acid amide is not particularly limited, and examples thereof include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide. The unsaturated fatty acid amide is not particularly limited, and examples thereof include oleic acid amide and erucic acid amide.

  The substituted amide is not particularly limited, and examples thereof include N-oleyl palmitate, N-stearyl stearate, N-stearyl oleate, N-oleyl stearate, N-stearyl erucic acid. Examples include amides. The methylolamide is not particularly limited, and examples thereof include methylol stearamide.

  The saturated fatty acid bisamide is not particularly limited. For example, methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, ethylene bisstearic acid amide, ethylene bishydroxystearic acid amide, ethylene Bisbehenic acid amide, hexamethylene bisstearic acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, N, N′-distearyl adipic acid amide, N, N′-distearyl sebacic acid amide, etc. It is done.

  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′-dioleyl sebacic acid amide and the like. Can be mentioned.

  The fatty acid ester amide is not particularly limited, and examples thereof include stearamide ethyl stearate. The aromatic bisamide is not particularly limited, and examples thereof include m-xylylene bis stearic acid amide, m-xylylene bishydroxy stearic acid amide, N, N′-cysteallyl isophthalic acid amide, and the like. Can be mentioned.

  The thickness of the sealant film 3 is preferably set to 10 μm to 100 μm. When the thickness is 10 μm or more, the occurrence of pinholes can be sufficiently prevented, and by setting the thickness to 100 μm or less, the amount of resin used can be reduced, and the cost can be reduced.

  When the two-layer laminated structure of FIG. 1 is adopted as the sealant film 3, the ratio of the thicknesses of the two layers is the thickness of the first unstretched film layer 7 / the thickness of the second unstretched film layer 8 = 5. It is preferable to be set in the range of ~ 90 / 95-10, and in particular, the thickness of the first unstretched film layer 7 / thickness of the second unstretched film layer 8 = in the range of 5-40 / 95-60. It is particularly preferred that it is set.

  2 is adopted as the sealant film 3, the ratio of the thickness of the three layers is the thickness of the first unstretched film layer 7 / the thickness of the second unstretched film layer 8. / Thickness of the third unstretched film layer 9 is preferably set in a range of 5 to 45/90 to 10/5 to 45, and in particular, the thickness of the first unstretched film layer 7 / second unstretched The thickness of the film layer 8 / the thickness of the third unstretched film layer 9 is particularly preferably set in the range of 5-20 / 90-60 / 5-20.

  In the case of adopting the two-layer laminated structure of FIG. 1 as the sealant film 3, the anti-blocking agent may be further contained in the second unstretched film layer 8 forming the innermost layer. In the case of adopting the three-layer laminated structure of FIG. 2 as the sealant film 3, the third unstretched film layer 9 forming the innermost layer may further contain an antiblocking agent. The anti-blocking agent is not particularly limited, and examples thereof include silica particles, acrylic resin particles, and aluminum silicate particles. The particle size of the antiblocking agent is preferably in the range of 0.1 μm to 10 μm in terms of average particle size, and more preferably in the range of 1 μm to 5 μm in terms of average particle size. When the anti-blocking agent is contained in the second unstretched film layer 8 forming the innermost layer or the third unstretched film layer 9 forming the innermost layer, the concentration of the antiblocking agent is set to 100 ppm to 5000 ppm. preferable.

  By containing the anti-blocking agent (particles) in the innermost layer, minute protrusions are formed on the surface of the innermost layer (8a in FIG. 1, 9a in FIG. 2), and the contact area between the films is reduced, so that the sealant films Can be blocked. Moreover, the slip property at the time of the shaping | molding can further be improved by containing an anti blocking agent (particle | grains) with the said lubricant.

  The sealant film 3 is preferably manufactured by a molding method such as multilayer extrusion molding, inflation molding, T-die cast film molding or the like.

  The power storage device exterior material 1 according to the present invention is manufactured using the sealant film 3 having the above-described configuration.

  The first manufacturing method according to the present invention (a method for manufacturing a power storage device exterior material) will be described. First, the laminated body of the structure which laminated | stacked the sealant film 3 of the said invention (1st invention or 2nd invention) and the metal foil 4 via the 1st adhesive agent (inner side adhesive) 6 is prepared. At this time, the first unstretched film layer 7 of the sealant film 3 is in contact with the first adhesive 6. Next, the obtained laminated body is subjected to a heat treatment (an aging treatment is performed), whereby the power storage device exterior material 1 of the present invention can be obtained.

  Next, the second manufacturing method according to the present invention (a manufacturing method of a power storage device exterior material) will be described. A heat-resistant resin film (outer layer) 2 is laminated on one surface of the metal foil 4 via a second adhesive (outer adhesive) 5 and a first adhesive (inner side) on the other surface of the metal foil 4. The laminated body of the structure by which the sealant film 3 of the said this invention (1st invention or 2nd invention) was laminated | stacked via the adhesive agent 6 was prepared. At this time, the first unstretched film layer 7 of the sealant film 3 is in contact with the first adhesive (inner adhesive) 6 (see FIGS. 1 and 2). Next, by heat-treating the obtained laminate (aging treatment), the electricity storage device exterior material 1 of the present invention having the configuration shown in FIGS. 1 and 2 can be obtained. That is, the exterior device 1 for an electricity storage device of the present invention obtained through such an aging treatment is formed of a heat resistant resin via a second adhesive layer (outer adhesive layer) 5 on one surface of the metal foil layer 4. A layer (outer layer) 2 is laminated and integrated, and an inner sealant layer (sealant film) (inner layer) is disposed on the other surface of the metal foil layer 4 via a first adhesive layer (inner adhesive layer) 6. 3 is a laminated and integrated structure (see FIGS. 1 and 2). When the sealant film of the first invention is used as the sealant film 3, the second unstretched film layer 8 of the sealant film 3 forms the innermost layer (see FIG. 1). When the sealant film of the second invention is used as the sealant film 3, the third unstretched film layer 9 of the sealant film 3 forms the innermost layer (see 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. The second adhesive (outer adhesive) 5 is not particularly limited, and examples thereof include a thermosetting adhesive. Although it does not specifically limit as said thermosetting adhesive, For example, an olefin type adhesive agent, an epoxy-type adhesive agent, an acrylic adhesive agent etc. are mentioned.

  The heating temperature for the aging treatment is preferably set to 65 ° C. or less, and in particular, from the viewpoint of maintaining the appropriate amount of lubricant present in the innermost layer of the exterior material and the degree of curing of the adhesive. It is more preferable to set to. Further, the heating time of the aging treatment varies depending on the type of adhesive, so it may be longer than the time required to obtain a sufficient adhesive strength according to the type of adhesive, but considering the lead time of the process The heating time is preferably as short as possible as long as sufficient adhesive strength is obtained.

  Since the sealant film of the present invention (the first invention or the second invention) described above is used as the sealant film 3 used for production, the exterior device 1 for an electricity storage device obtained through the above aging treatment has excellent moldability. In addition to being excellent, white powder is hardly exposed on the surface, and sufficient laminate strength and sufficient seal strength can be obtained.

In the outer package 1 for a power storage device obtained through the aging process, the lubricant amount existing on the outermost layer of the surface is preferably in the range of ^{0.1μg / cm 2 ~1.0μg / cm 2} . That is, when the sealant film of the first invention is used as the sealant film 3, the amount of lubricant present on the surface 8a of the second unstretched film layer 8 is 0.1 μg / cm ^{2 to} 1.0 μg / cm ^2. (See FIG. 1), and when the sealant film of the second invention is used as the sealant film 3, the amount of lubricant present on the surface 9a of the third unstretched film layer 9 is 0. preferably in the range of ^{.1μg / cm 2 ~1.0μg / cm 2} ( see FIG. 2). Among them, in the above aging treatment outer package 1 for a power storage device obtained through the, the lubricant amount existing the innermost layer of the surface 8a, the 9a is in the range of 0.1μg / cm ² ~0.6μg / cm ² Is more preferable.

  In the exterior device 1 for an electricity storage device of the present invention, the inner sealant layer (inner layer) 3 has excellent chemical resistance against a highly corrosive electrolytic solution used in a lithium ion secondary battery or the like. At the same time, it plays a role of imparting heat sealability to the exterior material.

  The heat-resistant resin layer (base material layer; outer layer) 2 is not an essential constituent layer, but is second bonded to the other surface (the surface opposite to the inner sealant layer) of the metal foil layer 4. It is preferable to adopt a configuration in which the heat-resistant resin layer 2 is laminated via an agent layer (outer adhesive layer) 5 (see FIGS. 1 and 2). By providing such a heat-resistant resin layer 2, sufficient insulation can be secured on the other surface (surface opposite to the inner sealant layer) side of the metal foil layer 4. Physical strength and impact resistance can be improved.

  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 seal temperature when heat-sealing the exterior material is used. As the heat-resistant resin, in the first invention, it is preferable to use a heat-resistant resin having a melting point that is 10 ° C. higher than the melting point of the resin constituting the second unstretched film layer 8. 3 It is preferable to use a heat resistant resin having a melting point higher by 10 ° C. than the melting point of the resin constituting the unstretched film layer 9.

  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 these stretched films are preferably used. Among them, the heat-resistant resin layer 2 includes a biaxially stretched polyamide film such as a biaxially stretched nylon film, a biaxially stretched polybutylene terephthalate (PBT) film, a biaxially stretched polyethylene terephthalate (PET) film or a biaxially stretched polyethylene film. It is particularly preferable to use a phthalate (PEN) film. The nylon film is not particularly limited, and examples thereof include 6 nylon film, 6,6 nylon film, MXD nylon film, and the like. The heat-resistant resin layer 2 may be formed as a single layer, or may be formed as a multilayer composed of a polyester film / polyamide film (such as a multilayer composed of PET film / nylon film). Also good.

  The heat-resistant resin layer (outer layer) 2 preferably has a thickness of 2 μm to 50 μm. When using a polyester film, the thickness is preferably 2 μm to 50 μm, and when using a nylon film, the thickness is preferably 7 μm to 50 μm. By setting it above the above preferred lower limit value, it is possible to ensure sufficient strength as an exterior material, and by setting it below the above preferred upper limit value, it is possible to reduce the stress at the time of molding such as stretch forming, draw forming, etc. and improve moldability Can be made.

  The metal foil layer 4 plays a role of imparting a gas barrier property to the exterior material 1 to prevent entry of oxygen and moisture. Although 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 these, aluminum foil and SUS foil (stainless steel foil) are used. Is preferred. The thickness of the metal foil layer 4 is preferably 5 μm to 120 μm. When it is 5 μm or more, it can prevent the occurrence of pinholes during rolling when producing a metal foil, and when it is 120 μm or less, it can reduce the stress during forming such as stretch forming and draw forming, thereby improving formability. be able to. Among these, 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 on at least the inner surface (the surface on the inner sealant layer 3 side). By performing such a chemical conversion treatment, corrosion of the metal foil surface by the contents (battery electrolyte or the like) can be sufficiently prevented. For example, the metal foil is subjected to chemical conversion treatment by the following treatment. That is, for example, on the surface of the metal foil that has been degreased,
1) phosphoric acid;
Chromic acid,
An aqueous solution of a mixture comprising at least one compound selected from the group consisting of a metal salt of fluoride and a nonmetal salt of fluoride; 2) phosphoric acid;
At least one resin selected from the group consisting of acrylic resins, chitosan derivative resins and phenolic resins;
An aqueous solution of a mixture comprising at least one compound selected from the group consisting of chromic acid and a chromium (III) salt, 3) 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 a chromium (III) salt;
An aqueous solution of a mixture comprising at least one compound selected from the group consisting of a fluoride metal salt and a fluoride non-metal salt. After applying an aqueous solution of any one of the above 1) to 3), drying is performed. Then, chemical conversion treatment is performed.

The conversion coating, chromium coating weight preferably is 0.1mg / m ² ~50mg / m ² as a (per one surface), in particular 2mg / m ² ~20mg / m 2 preferred.

  The thickness of the second adhesive layer (outer adhesive layer) 5 is preferably set to 1 μm to 5 μm. Among these, it is particularly preferable that the thickness of the outer adhesive layer 5 is set to 1 μm to 3 μm from the viewpoint of reducing the thickness and weight of the exterior material 1.

  The thickness of the first adhesive layer (inner adhesive layer) 6 is preferably set to 1 μm to 5 μm. Among these, it is particularly preferable that the thickness of the inner adhesive layer 6 is set to 1 μm to 3 μm from the viewpoint of reducing the thickness and weight of the exterior material 1.

  The packaging material 1 for an electricity storage device of the present invention is used as, for example, a packaging material for a lithium ion secondary battery. The electricity storage device exterior material 1 may be used as an exterior material without being molded (see FIG. 4), or may be used for molding such as deep drawing molding, overhang molding, etc. (See FIG. 4).

  One Embodiment of the electrical storage device 30 comprised using the exterior material 1 for electrical storage devices of this invention is shown in FIG. The electricity storage device 30 is a lithium ion secondary battery. In this embodiment, as shown in FIGS. 3 and 4, an exterior member 15 is configured by an exterior case 10 obtained by molding the exterior material 1 and the planar exterior material 1. Accordingly, a power storage device main body 31 (electrochemical element or the like) 31 having a substantially rectangular parallelepiped shape is stored in the storage recess of the external case 10 obtained by molding the exterior material 1 of the present invention. On the inner sealant layer 3 side of the inner sealant layer 3 of the present invention without being molded, and the peripheral portion of the inner sealant layer 3 of the planar exterior material 1; The power storage device 30 of the present invention is configured by sealing and sealing the inner sealant layer 3 of the flange portion (sealing peripheral portion) 29 of the outer case 10 by heat sealing (FIG. 3). 4). The inner surface of the housing recess of the outer case 10 is an inner sealant layer 3, and the outer surface of the housing recess is a heat-resistant resin layer (outer layer) 2 (see FIG. 4). When the exterior material shown in FIG. 1 is used as the exterior material for forming the exterior case 10, the inner surface of the housing recess is the second unstretched film layer 8 as the innermost layer, and the exterior case 10 When the exterior material shown in FIG. 2 is used as the exterior material for forming the film, the inner surface of the housing recess is the third unstretched film layer 9 as the innermost layer.

  In FIG. 3, reference numeral 39 denotes a heat seal portion in which the peripheral portion of the exterior material 1 and the flange portion (sealing peripheral portion) 29 of the external case 10 are joined (welded). In the electricity storage device 30, the tip end portion of the tab lead connected to the electricity storage device main body 31 is led out of the exterior member 15, but is not shown.

  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 seal part 39 is preferably set to 0.5 mm or more. Sealing can be reliably performed by setting it as 0.5 mm or more. Especially, it is preferable to set the width | variety of the said heat seal part 39 to 3 mm-15 mm.

  In the above embodiment, the exterior member 15 has a configuration including the exterior case 10 obtained by molding the exterior material 1 and the planar exterior material 1 (see FIGS. 3 and 4). It is not particularly limited to such a combination. For example, the exterior member 15 may be composed of a pair of planar exterior materials 1 or may be composed of a pair of exterior cases 10. May be.

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

<Example 1>
After applying a chemical conversion treatment solution composed of phosphoric acid, polyacrylic acid (acrylic resin), chromium (III) salt compound, water, and alcohol on both surfaces of the aluminum foil 4 having a thickness of 40 μm, drying is performed at 180 ° C. Then, a chemical conversion film was formed. The amount of chromium deposited on this chemical film was 10 mg / m ² per side.

  Next, a biaxially stretched 6 nylon film 2 having a thickness of 25 μm was dry-laminated (laminated) on one surface of the chemical conversion-treated aluminum foil 4 via a two-component curable urethane adhesive 5.

  Next, a 12 μm-thick first unstretched film 7 containing an ethylene-propylene random copolymer and 100 ppm of erucic acid amide, an ethylene-propylene block copolymer, 2500 ppm of erucic acid amide, and 2000 ppm of silica particles These two layers are laminated by co-extrusion using a T-die so that two layers of a second unstretched film 8 having a thickness of 28 μm containing (anti-blocking agent; average particle diameter is 2 μm) are laminated. After the obtained sealant film (first unstretched film layer 7 / second unstretched film layer 8) 3 having a thickness of 40 μm is obtained, the first unstretched film layer 7 surface of the sealant film 3 is cured in two parts. Overlaid on the other surface of the aluminum foil 4 after the dry lamination via a maleic acid-modified polypropylene adhesive 6 of the type 1 is sandwiched between a rubber nip roll and a laminating roll heated to 100 ° C. and subjected to pressure laminating, and then aged (heated) at 40 ° C. for 10 days, whereby the structure shown in FIG. An exterior material 1 for an electricity storage device was obtained.

As the two-component curable maleic acid-modified polypropylene adhesive, 100 parts by mass of maleic acid-modified polypropylene (melting point: 80 ° C., acid value: 10 mgKOH / g) as a main agent, isocyanurate of hexamethylene diisocyanate as a curing agent (NCO content: 20% by mass) 8 parts by mass, and using an adhesive solution in which a solvent is further mixed, the aluminum foil 4 has a solid content applied amount of 2 g / m ² . After applying to the other surface and heating and drying, the sealant film 3 was superposed on the surface of the first unstretched film layer 7.

In the obtained electricity storage device exterior material 1, the amount of lubricant present on the surface 8 a of the innermost layer (second unstretched film layer 8) of the exterior material 1 is 0.27 μg / cm ² , and the sealant film 3 of the exterior material The amount of lubricant present on the surface on the metal foil layer 4 side (surface of the first unstretched film layer 7) 7a was 0.38 μg / cm ² (see Table 1).

<Example 2>
Example except that the content concentration of erucic acid amide in the first unstretched film layer 7 before lamination was set to 0 ppm and the content concentration of erucic acid amide in the second unstretched film layer 8 before lamination was set to 3000 ppm. In the same manner as in Example 1, an exterior material 1 for an electricity storage device having the configuration shown in FIG.

<Example 3>
After applying a chemical conversion treatment solution composed of phosphoric acid, polyacrylic acid (acrylic resin), chromium (III) salt compound, water, and alcohol on both surfaces of the aluminum foil 4 having a thickness of 40 μm, drying is performed at 180 ° C. Then, a chemical conversion film was formed. The amount of chromium deposited on this chemical film was 10 mg / m ² per side.

  Next, a biaxially stretched 6 nylon film 2 having a thickness of 25 μm was dry-laminated (laminated) on one surface of the chemical conversion-treated aluminum foil 4 via a two-component curable urethane adhesive 5.

  Next, it comprises a first unstretched film 7 having a thickness of 6 μm containing an ethylene-propylene random copolymer and 100 ppm of erucamide, an ethylene-propylene block copolymer, and 2500 ppm of erucamide. A 6 μm thick second unstretched film 8 having a thickness of 28 μm, an ethylene-propylene random copolymer, 1000 ppm erucamide and 2000 ppm silica particles (anti-blocking agent; average particle diameter is 2 μm). The three unstretched films 9 are coextruded using a T-die so that three layers are laminated in this order, whereby a 40 μm thick sealant film (first unstretched film layer 7 is laminated). / Second unstretched film layer 8 / third unstretched film layer 9) 3, and then the sealant film 3 The surface of the first unstretched film layer 7 is overlaid on the other surface of the aluminum foil 4 after the dry lamination with a two-component curable maleic acid-modified polypropylene adhesive 6, and a rubber nip roll, 100 ° C. The laminate 1 is sandwiched between the laminated rolls heated to be dry-laminated by pressure bonding and then aged (heated) at 40 ° C. for 10 days, whereby the exterior device 1 for the electricity storage device having the configuration shown in FIG. 2 is obtained. Obtained.

As the two-component curable maleic acid-modified polypropylene adhesive, 100 parts by mass of maleic acid-modified polypropylene (melting point: 80 ° C., acid value: 10 mgKOH / g) as a main agent, isocyanurate of hexamethylene diisocyanate as a curing agent (NCO content: 20% by mass) 8 parts by mass, and using an adhesive solution in which a solvent is further mixed, the aluminum foil 4 has a solid content applied amount of 2 g / m ² . After applying to the other surface and heating and drying, the sealant film 3 was superposed on the surface of the first unstretched film layer 7.

In the obtained electricity storage device exterior material 1, the amount of lubricant present on the surface 9 a of the innermost layer (third unstretched film layer 9) of the exterior material is 0.25 μg / cm ² , and in the sealant film 3 of the exterior material The amount of lubricant present on the surface on the metal foil layer 4 side (the surface of the first unstretched film layer 7) 7a was 0.25 μg / cm ² (see Table 1).

<Example 4>
Example except that the concentration of erucamide in the first unstretched film layer 7 before lamination was set to 60 ppm and the concentration of erucamide in the second unstretched film layer 8 before lamination was set to 1000 ppm In the same manner as in Example 3, an exterior material 1 for an electricity storage device having the configuration shown in FIG.

<Example 5>
Except that the content concentration of erucic acid amide in the third unstretched film layer 9 before lamination was set to 500 ppm, an electricity storage device exterior material 1 having the configuration shown in FIG. 2 was obtained in the same manner as in Example 3.

<Example 6>
The content concentration of erucamide in the first unstretched film layer 7 before lamination is set to 60 ppm, the content concentration of erucamide in the second unstretched film layer 8 before lamination is set to 1000 ppm, and the first concentration before lamination is set to 1000 ppm. 3 An exterior material 1 for an electricity storage device having the configuration shown in FIG. 2 was obtained in the same manner as in Example 3 except that the concentration of erucamide in the unstretched film layer 9 was set to 2000 ppm.

<Example 7>
In the first unstretched film layer 7, the second unstretched film layer 8 and the third unstretched film layer 9, behenamide is used instead of erucamide as a lubricant, and Except that the content concentration of acid amide was set to 50 ppm, the electricity storage device exterior material 1 having the configuration shown in FIG. 2 was obtained in the same manner as in Example 3.

<Example 8>
In the same manner as in Example 7, except that oleic acid amide was used instead of erucic acid amide as a lubricant in the first unstretched film layer 7, the second unstretched film layer 8, and the third unstretched film layer 9, An exterior material 1 for an electricity storage device having the configuration shown in 2 was obtained.

<Example 9>
In the same manner as in Example 7, except that stearamide was used instead of erucamide as a lubricant in the first unstretched film layer 7, the second unstretched film layer 8, and the third unstretched film layer 9, the figure. An exterior material 1 for an electricity storage device having the configuration shown in 2 was obtained.

<Example 10>
Except that the erucamide content in the second unstretched film layer 8 before lamination was set to 4500 ppm, an electricity storage device exterior material 1 having the configuration shown in FIG. 2 was obtained in the same manner as in Example 3.

<Example 11>
Example except that the concentration of erucamide in the first unstretched film layer 7 before lamination was set to 0 ppm and the concentration of erucamide in the second unstretched film layer 8 before lamination was set to 2000 ppm In the same manner as in Example 3, an exterior material 1 for an electricity storage device having the configuration shown in FIG.

<Comparative Example 1>
An exterior material for an electricity storage device was obtained in the same manner as in Example 1 except that the concentration of erucic acid amide in the first unstretched film layer 7 before lamination was set to 400 ppm.

<Comparative Example 2>
Example except that the concentration of erucamide in the first unstretched film layer 7 before lamination was set to 50 ppm, and the concentration of erucamide in the second unstretched film layer 8 before lamination was set to 6000 ppm In the same manner as in Example 1, an exterior material for an electricity storage device was obtained.

<Comparative Example 3>
An exterior material for an electricity storage device was obtained in the same manner as in Example 3 except that the concentration of erucic acid amide in the first unstretched film layer 7 before lamination was set to 500 ppm.

<Comparative example 4>
Example except that the content concentration of erucic acid amide in the first unstretched film layer 7 before lamination was set to 400 ppm and the content concentration of erucic acid amide in the second unstretched film layer 8 before lamination was set to 1000 ppm. In the same manner as in Example 3, an exterior material for an electricity storage device was obtained.

<Comparative Example 5>
Example except that the concentration of erucamide in the first unstretched film layer 7 before lamination was set to 500 ppm and the concentration of erucamide in the third unstretched film layer 9 before lamination was set to 500 ppm In the same manner as in Example 3, an exterior material for an electricity storage device was obtained.

<Comparative Example 6>
The content concentration of erucic acid amide in the first unstretched film layer 7 before lamination is set to 360 ppm, the content concentration of erucic acid amide in the second unstretched film layer 8 before lamination is set to 1000 ppm, and the first concentration before lamination is set to 1000 ppm. 3 An exterior material for an electricity storage device was obtained in the same manner as in Example 3 except that the concentration of erucamide in the unstretched film layer 9 was set to 2000 ppm.

<Comparative Example 7>
In the first unstretched film layer 7, the second unstretched film layer 8 and the third unstretched film layer 9, behenamide is used instead of erucamide as a lubricant, and An exterior material for an electricity storage device was obtained in the same manner as in Example 3 except that the content concentration of acid amide was set to 320 ppm.

<Comparative Example 8>
In the same manner as in Comparative Example 7, except that oleic acid amide was used instead of erucic acid amide as a lubricant in first unstretched film layer 7, second unstretched film layer 8 and third unstretched film layer 9, A device exterior material was obtained.

<Comparative Example 9>
In the first unstretched film layer 7, second unstretched film layer 8 and third unstretched film layer 9, in the same manner as in Comparative Example 7 except that stearamide was used instead of erucamide as a lubricant, A device exterior material was obtained.

<Comparative Example 10>
Example except that the concentration of erucamide in the first unstretched film layer 7 before lamination was set to 400 ppm and the concentration of erucamide in the second unstretched film layer 8 before lamination was set to 4500 ppm. In the same manner as in Example 3, an exterior material for an electricity storage device was obtained.

<Comparative Example 11>
Example except that the concentration of erucamide in the first unstretched film layer 7 before lamination was set to 60 ppm and the concentration of erucamide in the second unstretched film layer 8 before lamination was set to 100 ppm. In the same manner as in Example 3, an exterior material for an electricity storage device was obtained.

<Comparative Example 12>
An exterior material for an electricity storage device was obtained in the same manner as in Example 3 except that the content concentration of erucic acid amide in the second unstretched film layer 8 before lamination was set to 5500 ppm.

<Comparative Example 13>
An exterior material for an electricity storage device was obtained in the same manner as in Example 3 except that the concentration of erucic acid amide in the third unstretched film layer 9 before lamination was set to 100 ppm.

<Comparative example 14>
The content concentration of erucamide in the first unstretched film layer 7 before lamination is set to 60 ppm, the content concentration of erucamide in the second unstretched film layer 8 before lamination is set to 1000 ppm, and the first concentration before lamination is set to 1000 ppm. 3 An exterior material for an electricity storage device was obtained in the same manner as in Example 3 except that the concentration of erucic acid amide in the unstretched film layer 9 was set to 4000 ppm.

  Each power storage device exterior material (aged) obtained as described above was evaluated based on the following evaluation method. The results are shown in Tables 1 and 2.

  The dynamic friction coefficients shown in Tables 1 and 2 are dynamic friction coefficients measured on the innermost surface of each power storage device exterior material (aged) in accordance with JIS K7125-1995 (see FIGS. 1 and 2). ). The surface of the innermost layer is the surface 8a of the second unstretched film layer in Examples 1 and 2 and Comparative Examples 1 and 2, and the surface of the third unstretched film layer in Examples 3-11 and Comparative Examples 3-14. This is the surface 9a (see FIGS. 1 and 2).

<Evaluation method of the amount of lubricant present on the surface of the innermost layer of the exterior material>
After cutting out two rectangular test pieces each having a length of 100 mm and a width of 100 mm from the outer packaging material for each power storage device, the two test pieces were superposed and the peripheral portions of the inner sealant layers were heat sealed at 200 ° C. A bag was prepared by heat sealing. 1 mL of acetone was injected into the interior space of the bag body using a syringe and left for 3 minutes in a state where the innermost surface of the inner sealant layer was in contact with acetone, and then the acetone in the bag body was extracted. By measuring and analyzing the amount of lubricant contained in the extracted liquid using a gas chromatograph, the amount of lubricant (μg / cm ² ) present on the surface of the innermost layer of the exterior material was determined. That is, the amount of lubricant per 1 cm ² of the surface of the innermost layer was determined.

<Evaluation method of amount of lubricant present on surface 7a of first unstretched film layer in exterior material>
The sealant film 3 prepared by coextrusion in each Example and each Comparative Example was cut into a rectangular shape with a length of 200 mm and a width of 200 mm, and then aged at 40 ° C. for 10 days. After cutting out two rectangular test pieces having a length of 100 mm and a width of 100 mm from the aged film, the two test pieces were overlapped so that the first unstretched film layers 7 were in contact with each other. Was covered with a nylon film, and the periphery was heat-sealed at a heat-sealing temperature of 200 ° C. to prepare a bag. After injecting 1 mL of acetone into the interior space of the bag using a syringe and leaving the surface of the first unstretched film layer (inner surface of the bag) in contact with acetone for 3 minutes, Acetone was extracted. The amount of lubricant (μg / cm ² ) present on the surface 7a of the first unstretched film layer was determined by measuring and analyzing the amount of lubricant contained in the extracted liquid using a gas chromatograph. That is, the amount of lubricant per 1 cm ² of the surface of the first unstretched film layer was determined.

<Formability evaluation method>
Using a straight mold free of forming depth, one-stage deep drawing is performed on the exterior material under the following forming conditions, and for each forming depth (9 mm, 8 mm, 7 mm, 6 mm, 5 mm, 4 mm, 3 mm, 2 mm). Formability was evaluated, and the maximum forming depth (mm) at which good forming with no pinholes at the corners could be performed was examined. In the judgment, “◯” indicates that the maximum molding depth is 5 mm or more, “△” indicates that the maximum molding depth is 2 mm or more and less than 5 mm, and “×” indicates that the maximum molding depth is less than 2 mm. " The presence / absence of a pinhole was examined by visually observing the presence / absence of transmitted light passing through the pinhole.
(Molding condition)
Mold: Punch: 33.3 mm x 53.9 mm, Die: 80 mm x 120 mm, Corner R: 2 mm, Punch R: 1.3 mm, Die R: 1 mm
Wrinkle holding pressure: Gauge pressure: 0.475 MPa, actual pressure (calculated value): 0.7 MPa
Material: SC (carbon steel) material, punch R only is chrome plated.

<Evaluation method for white powder>
After cutting out a rectangular test piece having a length of 600 mm and a width of 100 mm from the outer packaging material for each power storage device, the test piece obtained was placed on the inner sealant layer 3 surface (that is, the innermost surface 8a or 9a) on the test stand. A SUS weight (mass 1.3 kg, grounding surface size 55 mm × 50 mm) in which a black cloth was wound and the surface was black was placed on the upper surface of the test piece. In this state, the weight was pulled in a horizontal direction parallel to the upper surface of the test piece at a pulling speed of 4 cm / second, and the weight was pulled and moved over a length of 400 mm in contact with the upper surface of the test piece. The waste (black) on the contact surface of the weight after the tensile movement was visually observed, and the white powder on the surface of the waste (black) was markedly marked “x”, and white powder was generated to some extent (medium). The thing was set as "(triangle | delta)", and the thing which hardly had white powder or the white powder was not recognized was set as "(circle)". In addition, as the black waste, “Static removal sheet SSD2525 3100” manufactured by TRUSCO was used.

<Seal strength evaluation method>
After cutting out two test bodies having a width of 15 mm and a length of 150 mm from the obtained exterior material, Tester Sangyo Co., Ltd. in a state in which these two test bodies were overlapped so that the inner sealant layers were in contact with each other. Using a heat seal device (TP-701-A) manufactured by the manufacturer, heat seal is performed by single-sided heating under the conditions of heat seal temperature: 200 ° C., seal pressure: 0.2 MPa (gauge display pressure), and seal time: 2 seconds. went.

  Next, with respect to a pair of exterior materials in which the inner sealant layers are heat-sealed as described above, the exterior materials are manufactured using Shimadzu Access Corp. strograph (AGS-5kNX) in accordance with JIS Z0238-1998. The peel strength when the (test body) was peeled 90 degrees between the sealant inner sealant layers at a tensile rate of 100 mm / min was measured, and this was taken as the seal strength (N / 15 mm width).

  The seal strength of 30 N / 15 mm width or more was designated as “◯” (pass), and the seal strength less than 30 N / 15 mm width was designated as “X”.

<Evaluation method of cohesion degree of peeling interface>
After measuring the above sealing strength (peel strength), both sides of the peeled portion (destructed portion) of the inner sealant layer of the exterior material are visually observed, and the presence or absence or degree of whitening of the peeled portion (destructed portion) on both sides It can be judged that the stronger the strength, the greater the degree of aggregation).
(Criteria)
“○” indicates that whitening is remarkable and the degree of aggregation is large, “△” indicates that whitening occurs to some extent and the degree of aggregation is moderate, and “white” is not observed or there is almost no whitening and the degree of aggregation is The lower one was marked “x”.

<Lamination strength evaluation method>
A test specimen having a width of 15 mm and a length of 150 mm was cut out from the obtained exterior material, and the inner sealant layer 3 and the metal foil layer (aluminum foil layer) were immersed in an alkaline stripping solution at the end in the length direction of the test specimen. 4) was peeled off. In accordance with JIS K6854-3 (1999), using a strut (AGS-5kNX) manufactured by Shimadzu Corporation, a laminate including the metal foil layer (aluminum foil layer) 4 is sandwiched and fixed with one chuck, The peeled sealant layer 3 is sandwiched and fixed by the other chuck, and in this state, the peel strength when the T-type peel is performed at a tensile speed of 100 mm / min is measured, and this is measured with the inner sealant layer 3 and the metal foil layer 4. The laminate strength (adhesive strength) was (N / 15 mm width). The peel strength was measured in a 25 ° C. environment. Evaluation was made based on the following criteria.
(Criteria)
The case where the laminate strength was “5.0 N / 15 mm width” or more was “◯”, and the case where the laminate strength was less than “5.0 N / 15 mm width” was “x”.

  As is clear from Table 1, the electricity storage device exterior material of the present invention of Examples 1 to 11 configured using the sealant film of the present invention is excellent in moldability and is on the innermost surface of the exterior material. While white powder was difficult to be exposed, sufficient laminate strength and sufficient seal strength were obtained.

  On the other hand, in Comparative Examples 1-10 that deviated from the specified range of the present invention, sufficient laminate strength was not obtained. Further, in Comparative Examples 2 and 8, the seal strength was insufficient. Further, in Comparative Examples 11 and 13 that deviated from the specified range of the present invention, the moldability was poor, and in Comparative Example 14, white powder was generated on the surface of the innermost layer, and in Comparative Example 12, white powder was generated on the surface of the innermost layer. The seal strength was insufficient and the laminate strength was insufficient.

Examples of the exterior device for an electricity storage device manufactured using the sealant film according to the present invention, the exterior material for an electrical storage device according to the present invention, and the exterior material for an electrical storage device obtained by the production method of the present invention include, for example, ,
-Power storage devices such as lithium secondary batteries (lithium ion batteries, lithium polymer batteries, etc.)-Used as exterior materials for various power storage devices such as lithium ion capacitors, electric double layer capacitors, all solid state batteries

DESCRIPTION OF SYMBOLS 1 ... Exterior material for electrical storage devices 2 ... Heat-resistant resin layer (outer layer)
3 ... Inner sealant layer (sealant film) (inner layer)
4 ... Metal foil layer 5 ... Second adhesive layer (outer adhesive layer)
6 ... 1st adhesive layer (inner side adhesive layer)
7 ... 1st unstretched film layer (metal foil layer side)
7a: surface 8 on the metal foil layer side in the inner sealant layer ... second unstretched film layer 8a ... innermost layer surface 9 ... third unstretched film layer 9a ... innermost layer surface 10 ... outer case for power storage device (molded article) )

Claims (13)

A sealant film comprising a laminate of two or more layers including a first unstretched film layer and a second unstretched film layer laminated on one surface of the first unstretched film layer,
The first unstretched film layer is a layer disposed on the most metal foil side in the sealant film,
The first unstretched film layer contains a random copolymer containing propylene and other copolymer components excluding propylene as a copolymer component,
The first unstretched film layer has a configuration that does not contain a lubricant, or a configuration that contains a lubricant in excess of 0 ppm to 250 ppm,
The second unstretched film layer contains a propylene polymer and a lubricant,
A sealant film for an exterior material for an electricity storage device, wherein the content concentration of the lubricant in the second unstretched film layer is 500 ppm to 5000 ppm.   The second non-stretched film layer further includes a third non-stretched film layer laminated on a surface opposite to the side on which the first non-stretched film layer is laminated. 2. A random copolymer containing propylene and other copolymer components excluding propylene as a polymerization component, and a lubricant, and the concentration of the lubricant in the third unstretched film layer is 200 ppm to 3000 ppm. A sealant film for an exterior material of an electricity storage device according to 1.   The sealant film for an exterior material of an electricity storage device according to claim 2, wherein the lubricant-containing concentration in the second unstretched film layer is 1.0 to 5.0 times the lubricant-containing concentration in the third unstretched film layer. . An inner sealant layer comprising the sealant film according to claim 1 and a metal foil layer laminated on one side of the inner sealant layer, wherein the amount of lubricant present on the surface of the second unstretched film layer is 0. exterior material for a power storage device which is a range of ^{1μg / cm 2 ~1.0μg / cm 2} . An inner sealant layer comprising the sealant film according to claim 2 and a metal foil layer laminated on one side of the inner sealant layer, wherein the amount of lubricant present on the surface of the third unstretched film layer is exterior material for a power storage device which is a range of ^{0.1μg / cm 2 ~1.0μg / cm 2} . A heat-resistant resin layer as an outer layer, an inner sealant layer made of the sealant film according to claim 1, and a metal foil layer disposed between both layers, and present on the surface of the second unstretched film layer exterior material for a power storage device that lubricant amount is equal to or in the range of 0.1μg / cm ² ~1.0μg / cm ² to. A surface of the third unstretched film layer, comprising: a heat-resistant resin layer as an outer layer; an inner sealant layer comprising the sealant film according to claim 2; and a metal foil layer disposed between the two layers. exterior material for a power storage device, wherein the lubricant amount existing in the range of 0.1μg / cm ² ~1.0μg / cm ² in.   The exterior case for electrical storage devices which consists of a molded object of the exterior material of any one of Claims 4-7. Preparing a laminate in which the sealant film according to any one of claims 1 to 3 and a metal foil are laminated via a first adhesive;
An aging step of obtaining a power storage device exterior material by heat-treating the laminate, and a method for producing a power storage device exterior material.   The method for manufacturing an exterior material for an electricity storage device according to claim 9, wherein the first adhesive is a thermosetting adhesive. The heat-resistant resin film is laminated on one surface of the metal foil via a second adhesive, and at the other surface of the metal foil, the first adhesive is interposed on the other surface. Preparing a laminate having a structure in which the sealant film is laminated;
An aging step of obtaining a power storage device exterior material by heat-treating the laminate, and a method for producing a power storage device exterior material.   The method for manufacturing an exterior material for an electricity storage device according to claim 11, wherein the first adhesive is a thermosetting adhesive, and the second adhesive is a thermosetting adhesive. Any one of claims 9 to 12 lubricant amount existing on the outermost layer of the surface is in the range of 0.1μg / cm ² ~1.0μg / cm ² of obtained by heating the storage device for exterior materials The manufacturing method of the exterior | packing material for electrical storage devices of description.

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