Power storage device, exterior film, and method for manufacturing power storage device

Abstract

To provide a power storage device that has improved in sealing performance and can restrain conduction between a positive electrode and a negative electrode even when a laminated film is joined to a lid body or an electrode terminal, an exterior film to be used in the power storage device, and a method for manufacturing the power storage device.SOLUTION: A power storage device includes an electrode body, an exterior film that wraps the electrode body so as to seal the electrode body, and positive and negative electrode members that are connected to the electrode body and are configured to contain a conductive material. A laminate film includes a first conductive barrier layer, a second conductive barrier layer, and an insulating layer that is laminated on the first and second conductive barrier layers to prevent electrical conduction between the first and second conductive barrier layers. The first conductive barrier layer is bonded directly to the positive electrode member or bonded to the positive electrode member via an insulating layer. The second conductive barrier layer is bonded directly to the negative electrode member or bonded to the negative electrode member via the insulating layer.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a power storage device, an exterior film, and a method for manufacturing a power storage device.

Background Art

[0002] Patent Document 1 discloses an example of a power storage device. This power storage device includes an electrode body including a current collector, an exterior body that seals the electrode body, and an electrode terminal connected to the current collector. The exterior body includes a laminated film that wraps the electrode body and a lid body joined to the laminated film. The electrode terminal is inserted into a through-hole formed in the lid body. The end of the current collector is joined to the electrode terminal.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above power storage device, it is conceivable to omit the lid body and join the heat-sealable resin layer of the laminated film and the electrode terminal by heat sealing, for example, via an adhesive film. However, when joining the heat-sealable resin layer of the laminated film and the electrode terminal via an adhesive film, the time required for joining is long, and the joining strength between the laminated film and the electrode terminal is low. For this reason, the sealing performance of the power storage device is low. On the other hand, when joining the conductive barrier layer of the laminated film and the electrode terminal by welding, the time required for joining can be shortened compared to the case of joining the laminated film and the electrode terminal by heat sealing. However, the electrode terminal connected to the positive electrode of the electrode body and the electrode terminal connected to the negative electrode are electrically connected through the conductive barrier layer of the laminated film, and current cannot be output. Note that such problems also occur in the above power storage device when joining a lid body made of a conductive material and the laminated film.

[0005] The present invention aims to provide a power storage device that enhances sealing performance and suppresses conduction between a positive electrode and a negative electrode even when a laminated film is joined to a lid body or an electrode terminal, a laminated film used for this power storage device, and a method for manufacturing this power storage device.

Means for Solving the Problems

[0006] The power storage device according to the first aspect of the present invention includes an electrode body, a laminated film that wraps the electrode body so as to seal the electrode body, a positive electrode member and a negative electrode member that are connected to the electrode body and are composed of a conductive material. The laminated film includes a first conductive barrier layer, a second conductive barrier layer, and an insulating layer laminated on the first conductive barrier layer and the second conductive barrier layer so that the first conductive barrier layer and the second conductive barrier layer do not conduct. The first conductive barrier layer is directly joined to the positive electrode member or joined to the positive electrode member via the insulating layer, and the second conductive barrier layer is directly joined to the negative electrode member or joined to the negative electrode member via the insulating layer.

[0007] The power storage device according to the second aspect of the present invention is the power storage device according to the first aspect, wherein the insulating layer is laminated between the first conductive barrier layer and the second conductive barrier layer in the lamination direction of the laminated film.

[0008] The power storage device according to the third aspect of the present invention is the power storage device according to the second aspect, wherein the laminated film includes a portion where the first conductive barrier layer, the insulating layer, and the second conductive barrier layer overlap in a plan view.

[0009] The power storage device according to the fourth aspect of the present invention is the power storage device according to any one of the first to third aspects, wherein a gap is formed between the first conductive barrier layer and the second conductive barrier layer.

[0010] The power storage device according to the fifth aspect of the present invention is the power storage device according to the fourth aspect, wherein the first conductive barrier layer and the second conductive barrier layer are laminated on the same surface of the insulating layer.

[0011] The power storage device according to the sixth aspect of the present invention is the power storage device according to any one of the first to fifth aspects, and has a positive electrode joint portion which is a portion where the first conductive barrier layer and the positive electrode member are directly joined, and the insulating layer is adjacent to the positive electrode joint portion.

[0012] The power storage device according to the seventh aspect of the present invention is the power storage device according to any one of the first to sixth aspects, and has a negative electrode joint portion which is a portion where the second conductive barrier layer and the negative electrode member are directly joined, and the insulating layer is adjacent to the negative electrode joint portion.

[0013] The power storage device according to the eighth aspect of the present invention is the power storage device according to any one of the first to seventh aspects, and the material constituting the insulating layer contains an insulating filler.

[0014] The power storage device according to the ninth aspect of the present invention is the power storage device according to any one of the first to eighth aspects, and the material constituting the insulating layer has gas barrier properties.

[0015] The power storage device according to the tenth aspect of the present invention is the power storage device according to any one of the first to ninth aspects, and at least one of the positive electrode member and the negative electrode member is a lid for sealing the electrode body together with the laminated film.

[0016] The power storage device according to the eleventh aspect of the present invention is the power storage device according to any one of the first to ninth aspects, and at least one of the positive electrode member and the negative electrode member is an electrode terminal.

[0017] The power storage device according to the twelfth aspect of the present invention is the power storage device according to any one of the first to eleventh aspects, and further has an outer bag that wraps the laminated film, the positive electrode member, and the negative electrode member.

[0018] The exterior film according to the 13th aspect of the present invention is a laminated film that wraps an electrode body of a power storage device. The power storage device includes a positive electrode member and a negative electrode member that are connected to the electrode body and are composed of a conductive material. The laminated film includes a first conductive barrier layer, a second conductive barrier layer, and an insulating layer laminated on the first conductive barrier layer and the second conductive barrier layer so that the first conductive barrier layer and the second conductive barrier layer do not conduct. The first conductive barrier layer is directly joined to the positive electrode member or joined to the positive electrode member via the insulating layer. The second conductive barrier layer is directly joined to the negative electrode member or joined to the negative electrode member via the insulating layer.

[0019] A method for manufacturing a power storage device according to the 14th aspect of the present invention includes an electrode body, a laminated film that wraps the electrode body so as to seal the electrode body, a positive electrode member and a negative electrode member that are connected to the electrode body and are composed of a conductive material. The laminated film includes a first conductive barrier layer, a second conductive barrier layer, and an insulating layer laminated on the first conductive barrier layer and the second conductive barrier layer so that the first conductive barrier layer and the second conductive barrier layer do not conduct. The first conductive barrier layer is directly joined to the positive electrode member or joined to the positive electrode member via the insulating layer. The second conductive barrier layer is directly joined to the negative electrode member or joined to the negative electrode member via the insulating layer. The method for manufacturing the power storage device includes a step of joining the first conductive barrier layer and the positive electrode member directly or via the insulating layer, and a step of joining the second conductive barrier layer and the negative electrode member directly or via the insulating layer.

Advantages of the Invention

[0020] According to the power storage device, the exterior film, and the method for manufacturing the power storage device of the present invention, it is possible to enhance the sealing property and suppress conduction between the positive electrode and the negative electrode even when the laminated film is joined to the lid body or the electrode terminal.

Brief Description of the Drawings

[0021]

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Embodiments for Carrying Out the Invention

[0022] Hereinafter, a power storage device according to an embodiment of the present invention will be described with reference to the drawings. In this specification, a numerical range indicated by "~" means "or more" and "or less". For example, the notation 2~15 mm means 2 mm or more and 15 mm or less.

[0023] [Embodiment] <1-1. Configuration of Power Storage Device> FIG. 1 is a plan view schematically showing a power storage device 10 according to the embodiment. FIG. 2 is a view of the exterior film provided in the power storage device of FIG. 1 in a spread state. FIG. 3 is a perspective view of a lid body 60 provided in the power storage device of FIG. 1. FIG. 4 is a cross-sectional view taken along line D4-D4 of FIG. 1. In FIG. 1, the direction of arrow UD indicates the thickness direction of the power storage device 10, the direction of arrow LR indicates the width direction of the power storage device 10, and the direction of arrow FB indicates the depth direction of the power storage device 10. The directions indicated by each of the arrows UDLRFB are common in the following figures.

[0024] The power storage device 10 includes an electrode body 20 including a current collector 30 and an exterior body 40. The electrode body 20 includes, for example, electrodes (positive electrode and negative electrode) constituting a power storage member such as a lithium ion battery, a capacitor, an all-solid-state battery, a sodium ion battery, a semi-solid battery, a quasi-solid battery, a polymer battery, an all-resin battery, a lead storage battery, a nickel-hydrogen storage battery, a nickel-cadmium storage battery, a nickel-iron storage battery, a nickel-zinc storage battery, a silver oxide-zinc storage battery, a metal-air battery, a polyvalent cation battery, or a capacitor, and a separator and the like. In the present embodiment, the shape of the electrode body 20 is a substantially rectangular parallelepiped. Note that the "substantially rectangular parallelepiped" includes, in addition to a perfect rectangular parallelepiped, a solid that can be regarded as a rectangular parallelepiped by modifying the shape of a part of the outer surface, for example. The shape of the electrode body 20 may be, for example, a cylinder or a polygonal prism.

[0025] The exterior body 40 seals the electrode body 20. The exterior body 40 includes a laminated film 50 and a lid body 60. The laminated film 50 wraps the electrode body 20. In the present embodiment, the laminated film 50 is wound around the electrode body 20. The lid body 60 is disposed on the side of the electrode body 20 in the FB direction. In another example, the electrode body 20 may be accommodated inside a laminated film 50 configured in a cylindrical shape such that openings 40A are formed at both ends in the FB direction, and the openings 40A may be closed by the lid body 60. In yet another example, the electrode body 20 connected to the lid body 60 may be accommodated inside a laminated film 50 configured in a cylindrical shape such that the openings 40A are formed, and the openings 40A may be closed by the lid body 60.

[0026] Since the exterior body 40 seals the electrode body 20 by winding the laminated film 50 around the electrode body 20, the electrode body 20 can be easily sealed regardless of the thickness of the electrode body 20. In order to reduce the dead space between the electrode body 20 and the laminated film 50 to improve the volumetric energy density of the energy storage device 10, a state where the laminated film 50 is wound so as to contact the outer surface of the electrode body 20 is preferable. Also, in all-solid-state batteries, it is necessary to uniformly apply a high pressure from the outside of the battery in order to exhibit battery performance. Therefore, it is necessary to eliminate the space between the electrode body 20 and the laminated film 50, and thus a state where the laminated film 50 is wound so as to contact the outer surface of the electrode body 20 is preferable.

[0027] As shown in FIG. 4, the lid body 60 seals the electrode body 20 together with the laminated film 50. The shape of the lid body 60 can be arbitrarily selected as long as it can seal the electrode body 20. In the example shown in FIG. 3, the lid body 60 is plate-shaped. The lid body 60 has a positive electrode lid body 60X connected to the positive electrode and a negative electrode lid body 60Y connected to the negative electrode. The main configurations of the positive electrode lid body 60X and the negative electrode lid body 60Y are substantially the same. Therefore, hereinafter, when the positive electrode lid body 60X and the negative electrode lid body 60Y are not particularly distinguished, they are simply referred to as the lid body 60. Note that the positive electrode lid body 60X corresponds to the positive electrode member, and the negative electrode lid body 60Y corresponds to the negative electrode member.

[0028] The lid body 60 is configured to include a conductive material. In the present embodiment, "configured to include a conductive material" means that when the total amount of the materials constituting the lid body 60 is 100% by mass, the content rate of the conductive material is 50% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass or more. That is, the materials constituting the lid body 60 may contain materials other than the conductive material in addition to the conductive material. The lid body 60 configured to include a conductive material preferably has a corrosion-resistant film. The corrosion-resistant film refers to, for example, a thin film that is formed on the surface of the lid body 60 by performing a hot water conversion treatment such as boehmite treatment, a chemical conversion treatment, an anodizing treatment, a plating treatment such as nickel or chromium, or a corrosion prevention treatment of applying a coating agent, so that the lid body 60 has corrosion resistance (for example, acid resistance, alkali resistance, etc.). Specifically, the corrosion-resistant film means a film that improves the acid resistance of the lid body 60 (acid-resistant film), a film that improves the alkali resistance of the lid body 60 (alkali-resistant film), and the like. As the treatment for forming the corrosion-resistant film, one type may be performed, or two or more types may be combined. Also, it can be made into multiple layers instead of just one layer. Furthermore, among these treatments, the hot water conversion treatment and the anodizing treatment are treatments that dissolve the surface of the metal foil with a treatment agent and form a metal compound excellent in corrosion resistance. Note that these treatments may be included in the definition of the chemical conversion treatment. Also, when the lid body 60 has a corrosion-resistant film, the lid body 60 including the corrosion-resistant film is used.

[0029] The conductive material constituting the lid body 60 is, for example, a metal material. The metal material constituting the lid body 60 is, for example, aluminum, an aluminum alloy, nickel, copper, or a copper alloy. For example, when the electrode body 20 is a lithium-ion battery, the positive electrode lid body 60X connected to the positive electrode is preferably constituted by aluminum or an aluminum alloy. The negative electrode lid body 60Y connected to the negative electrode is preferably constituted by nickel, copper, or a copper alloy. The material constituting the negative electrode lid body 60Y may be copper with nickel plating. The materials constituting the lid body 60 may include recycled materials of metal materials.

[0030] The lid body 60 has a first surface 61, a second surface 62, and a film joint portion 63. The first surface 61 faces the electrode body 20. The first surface 61 is connected to one end portion 31 of the current collector 30 (see FIG. 4). In order to easily connect the lid body 60 and the current collector 30, a convex portion protruding toward the electrode body 20 may be formed on the first surface 61. The second surface 62 is a surface opposite to the first surface 61. In order to easily connect to an external device, a convex portion protruding outside the exterior body 40 in the FB direction may be formed on the second surface 62. The film joint portion 63 is connected to the first surface 61 and the second surface 62 and is joined to the first conductive barrier layer 51 or the second conductive barrier layer 52 of the laminated film 50 described later.

[0031] The film joint portion 63 includes a first joint surface 63A, a second joint surface 63B, a third joint surface 63C, and a fourth joint surface 63D. The first joint surface 63A constitutes the upper surface of the lid body 60. The first joint surface 63A extends in a first direction (in this embodiment, the LR direction) in a front view of the lid body 60. The second joint surface 63B and the third joint surface 63C are connected to the first joint surface 63A and constitute the side surface of the lid body 60. The second joint surface 63B and the third joint surface 63C extend in a second direction (in this embodiment, the UD direction) intersecting the first direction in a front view of the lid body 60. In this embodiment, in a front view of the lid body 60, the first direction and the second direction are orthogonal. The first direction and the second direction do not have to be orthogonal in a front view of the lid body 60. The fourth joint surface 63D constitutes the lower surface of the lid body 60. The fourth joint surface 63D extends in a first direction (in this embodiment, the LR direction) in a front view of the lid body 60.

[0032] When the lid body 60 is plate-shaped, even when the power storage devices 10 are stacked, the lid body 60 preferably has a certain thickness in the FB direction so that the exterior body 40 is prevented from deforming. From another perspective, when the lid body 60 is plate-shaped, the film joint portion 63 of the lid body 60 preferably has a certain thickness in the FB direction so that the film joint portion 63 of the lid body 60 and the laminated film 50 can be preferably joined when forming the second sealing portion 80 described later. The minimum value of the thickness of the lid body 60 in the FB direction is, for example, 1.0 mm, more preferably 3.0 mm, and even more preferably 4.0 mm. The maximum value of the thickness of the lid body 60 in the FB direction is, for example, 20 mm, more preferably 15 mm, and even more preferably 10 mm. The maximum value of the thickness of the lid body 60 in the FB direction may be 20 mm or more. The preferred range of the thickness of the lid body 60 in the FB direction is 1.0 mm to 20 mm, 1.0 mm to 15 mm, 1.0 mm to 10 mm, 3.0 mm to 20 mm, 3.0 mm to 15 mm, 3.0 mm to 10 mm, 4.0 mm to 20 mm, 4.0 mm to 15 mm, 4.0 mm to 10 mm. Note that the thickness of the lid body 60 may vary depending on the part of the lid body 60. When the thickness of the lid body 60 varies depending on the part, the thickness of the lid body 60 is the thickness of the thickest part.

[0033] The film joint portion 63 further includes boundaries 64, 65, 66, and 67. The boundary 64 is the boundary between the first joint surface 63A and the second joint surface 63B. The boundary 65 is the boundary between the first joint surface 63A and the third joint surface 63C. The boundary 66 is the boundary between the fourth joint surface 63D and the second joint surface 63B. The boundary 67 is the boundary between the fourth joint surface 63D and the third joint surface 63C. The shapes of the boundaries 64 to 67 may be corners or may be rounded by R processing. In the present embodiment, the boundaries 64 to 67 are corners.

[0034] A part of the film joint 63 may not be joined to the first conductive barrier layer 51 or the second conductive barrier layer 52 of the laminated film 50. A portion of the film joint 63 that is not joined to the first conductive barrier layer 51 or the second conductive barrier layer 52 of the laminated film 50 may be coated, for example, with a coating composed of a resin material. Here, "composed of a resin material" means that when the total amount of the materials constituting the coating is 100% by mass, the content of the resin material is 50% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. That is, the material constituting the coating can contain, in addition to the resin material, materials other than the resin material.

[0035] Specific examples of the resin include resins such as polyester, polyolefin, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, silicone resin, and phenol resin, and thermoplastic resins such as modified products of these resins. Further, the resin material may be a mixture of these resins, a copolymer, or a modified product of a copolymer. Among these, the resin material is preferably a heat-sealable resin such as polyester or polyolefin, and more preferably polyolefin. When the resin material is a resin, the coating 90 may be formed by any molding method.

[0036] The resin material contained in the covering material is preferably an olefin-based random copolymer, more preferably contains a resin containing a polyolefin backbone as a main component, still more preferably contains a polyolefin as a main component, and still more preferably contains polypropylene as a main component. The polyolefin may be an acid-modified polyolefin. It is preferable that a plurality of types of amide-based lubricants are present in the resin material contained in the covering material. Further, it is preferable that the resin material contained in the covering material further contains a plurality of types of amide-based lubricants including unsaturated fatty acid amides in addition to saturated fatty acid amides. The resin material contained in the covering material may be a polyolefin resin added with a propylene-based elastomer having a melting point higher than 150°C. Note that the main component is the component having the highest mass% among the materials contained in the constituent elements, for example, a material occupying 35 mass% or more, 50 mass% or more, 90 mass% or more, or 95 mass% or more.

[0037] Specific examples of the polyester include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, copolyester, and the like. Examples of the copolyester include copolyesters having ethylene terephthalate as the main repeating unit. Specifically, a copolymer polyester obtained by polymerizing ethylene isophthalate with ethylene terephthalate as the main repeating unit (hereinafter abbreviated following polyethylene(terephthalate / isophthalate)), polyethylene(terephthalate / adipate), polyethylene(terephthalate / sodium sulfoisophthalate), polyethylene(terephthalate / sodium isophthalate), polyethylene(terephthalate / phenyl-dicarboxylate), polyethylene(terephthalate / decanedicarboxylate), and the like can be mentioned. Among these, from the viewpoint of enhancing heat resistance and pressure resistance, the resin material is preferably polybutylene terephthalate.

[0038] In addition, specific examples of the polyolefin include polyethylene such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; ethylene-α-olefin copolymers; polypropylene such as homopolypropylene, block copolymers of polypropylene (for example, block copolymers of propylene and ethylene), random copolymers of polypropylene (for example, random copolymers of propylene and ethylene); propylene-α-olefin copolymers; and terpolymers of ethylene-butene-propylene. The polyolefin resin in the case of being a copolymer may be a block copolymer or a random copolymer. Among these, the resin material is preferably polypropylene because it is excellent in heat sealability and electrolyte resistance, and acid-modified polypropylene obtained by Kraft modification with an acid such as maleic anhydride is particularly preferred.

[0039] The resin as the resin material may contain a filler as necessary. Specific examples of the filler include glass beads, graphite, glass fibers, and carbon fibers. By the resin as the resin material containing the filler, the deformation resistance of the coating body 90 against temperature changes can be improved.

[0040] The melt mass flow rate of the resin material contained in the material constituting the coating body is preferably in the range of 1 g / 10 min to 100 g / 10 min, and more preferably in the range of 5 g / 10 min to 80 g / 10 min. The melt mass flow rate is measured based on JIS K7210-1:2014. The measurement temperature of the melt mass flow rate is 230 °C.

[0041] As shown in FIG. 4, the laminated film 50 is a laminate film including a first conductive barrier layer 51, a second conductive barrier layer 52, and an insulating layer 53. The first conductive barrier layer 51, the second conductive barrier layer 52, and the insulating layer 53 are laminated so that the first conductive barrier layer 51 and the second conductive barrier layer 52 are not electrically connected. In the present embodiment, the first conductive barrier layer 51, the insulating layer 53, and the second conductive barrier layer 52 are laminated in this order from the outside of the exterior body 40 toward the electrode body 20.

[0042] The first conductive barrier layer 51 and the second conductive barrier layer 52 are formed of a conductive material. The definition of "formed of a conductive material" is the same as in the case of the lid body 60. That is, the materials constituting the first conductive barrier layer 51 and the second conductive barrier layer 52 may contain materials other than the conductive material in addition to the conductive material. The conductive materials constituting the first conductive barrier layer 51 and the second conductive barrier layer 52 are, for example, aluminum, aluminum alloy, titanium, titanium alloy, steel (including stainless steel), copper, copper alloy, nickel, nickel alloy, magnesium, magnesium alloy, niobium, iron, antimony-doped tin oxide, or indium tin oxide doped with tin.

[0043] The first conductive barrier layer 51 is joined to the film joint portion 63 of the positive electrode lid body 60X. From the viewpoint of increasing the joining strength between the first conductive barrier layer 51 and the positive electrode lid body 60X, the conductive material contained in the material constituting the first conductive barrier layer 51 is preferably the same conductive material as the conductive material contained in the material constituting the positive electrode lid body 60X.

[0044] The second conductive barrier layer 52 is joined to the film joint portion 63 of the negative electrode lid body 60Y. From the viewpoint of increasing the joining strength between the second conductive barrier layer 52 and the negative electrode lid body 60Y, the conductive material contained in the material constituting the second conductive barrier layer 52 is preferably the same conductive material as the conductive material contained in the material constituting the negative electrode lid body 60Y.

[0045] The insulating layer 53 insulates the first conductive barrier layer 51 and the second conductive barrier layer 52 so that the first conductive barrier layer 51 and the second conductive barrier layer 52 do not conduct. The material constituting the insulating layer 53 can be arbitrarily selected as long as it can insulate the first conductive barrier layer 51 and the second conductive barrier layer 52. The material constituting the insulating layer 53 is, for example, resin or ceramic. The ceramic is, for example, an oxide, a nitride, a carbonate, or a hydroxide. The material constituting the insulating layer 53 may be a combination of a plurality of materials. From the viewpoint of preferably insulating the first conductive barrier layer 51 and the second conductive barrier layer 52, the material constituting the insulating layer 53 preferably contains an insulating filler. From the viewpoint of suppressing the intrusion of moisture into the exterior body 40, the material constituting the insulating layer 53 preferably has gas barrier properties, and particularly preferably has moisture barrier properties.

[0046] The resin is, for example, a thermoplastic resin such as polyester, polyolefin, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, silicone resin, phenolic resin, etc., fluororesin, and modified products of these resins. From the viewpoint of moisture barrier properties, the resin is preferably a thermoplastic resin such as fluororesin and modified products of fluororesin.

[0047] The oxide is, for example, magnesium oxide, silicon oxide, aluminum oxide, or tin oxide. These oxides have moisture barrier properties.

[0048] The nitride is, for example, aluminum nitride, boron nitride, or silicon nitride. From the viewpoint of moisture barrier properties, the nitride is preferably silicon nitride.

[0049] The carbonate is, for example, magnesium carbonate. The hydroxide is, for example, magnesium hydroxide. Magnesium carbonate and magnesium hydroxide have moisture barrier properties.

[0050] In plan view, the laminated film 50 preferably includes an overlapping portion 50X where the first conductive barrier layer 51, the insulating layer 53, and the second conductive barrier layer 52 overlap. When the laminated film 50 includes the overlapping portion 50X, even if the material constituting the insulating layer 53 does not have gas barrier properties, the gas barrier properties are enhanced by the first conductive barrier layer 51 and the second conductive barrier layer 52. In the present embodiment, the overlapping portion 50X is formed so as to cover substantially the entire upper and lower surfaces of the electrode body 20.

[0051] The first conductive barrier layer 51 extends further toward the positive electrode lid body 60X side than the second conductive barrier layer 52 and the insulating layer 53 in the FB direction. The first conductive barrier layer 51 of the portion including the third edge 50C (see FIG. 2) of the laminated film 50 is joined to the film joining portion 63 of the positive electrode lid body 60X, for example, by welding.

[0052] The second conductive barrier layer 52 extends further toward the negative electrode lid body 60Y side than the first conductive barrier layer 51 and the insulating layer 53 in the FB direction. The second conductive barrier layer 52 of the portion including the fourth edge 50D (see FIG. 2) of the laminated film 50 is joined to the film joining portion 63 of the negative electrode lid body 60Y, for example, by welding. From the viewpoint of suppressing the short circuit between the second conductive barrier layer 52 and the electrode body 20, it is preferable that another insulating layer is laminated on the surface of the second conductive barrier layer 52 opposite to the surface on which the insulating layer 53 is laminated.

[0053] From the viewpoint of suitably suppressing the conduction between the first conductive barrier layer 51 and the second conductive barrier layer 52, in the FB direction, the end portion 53X of the insulating layer 53 on the positive electrode lid body 60X side preferably exists at a position closer to the positive electrode lid body 60X than the end portion 52X of the second conductive barrier layer 52 on the positive electrode lid body 60X side.

[0054] From the viewpoint of suitably suppressing the conduction between the first conductive barrier layer 51 and the second conductive barrier layer 52, in the FB direction, the end portion 53Y of the insulating layer 53 on the negative electrode lid body 60Y side preferably exists at a position closer to the negative electrode lid body 60Y than the end portion 51Y of the first conductive barrier layer 51 on the negative electrode lid body 60Y side.

[0055] The thicknesses of the first conductive barrier layer 51 and the second conductive barrier layer 52 can be arbitrarily selected. The thicknesses of the first conductive barrier layer 51 and the second conductive barrier layer 52 are preferably about 200 μm or less, more preferably about 150 μm or less, still more preferably about 120 μm or less, and particularly preferably about 80 μm or less. Also, the thicknesses of the first conductive barrier layer 51 and the second conductive barrier layer 52 are preferably about 4 μm or more, still more preferably about 10 μm or more, and more preferably about 15 μm or more. Further, the preferable ranges of the thicknesses of the first conductive barrier layer 51 and the second conductive barrier layer 52 include about 4 to 200 μm, about 4 to 150 μm, about 4 to 120 μm, about 4 to 80 μm, about 10 to 200 μm, about 10 to 150 μm, about 10 to 120 μm, about 10 to 80 μm, about 15 to 200 μm, about 15 to 150 μm, about 15 to 120 μm, and about 15 to 80 μm. The thickness of the first conductive barrier layer 51 and the thickness of the second conductive barrier layer 52 may be different or the same.

[0056] The thickness of the insulating layer 53 can be arbitrarily selected. The thickness of the insulating layer 53 is preferably about 300 μm or less, more preferably about 200 μm or less, still more preferably about 150 μm or less, and particularly preferably about 120 μm or less. Also, the thickness of the insulating layer 53 is preferably about 5 μm or more, still more preferably about 15 μm or more, and more preferably about 30 μm or more. Further, the preferable ranges of the thickness of the insulating layer 53 include about 5 to 300 μm, about 5 to 200 μm, about 5 to 150 μm, about 5 to 120 μm, about 15 to 300 μm, about 15 to 200 μm, about 15 to 150 μm, about 15 to 120 μm, about 30 to 300 μm, about 30 to 200 μm, about 30 to 150 μm, and about 30 to 120 μm.

[0057] In this embodiment, with the laminated film 50 wound around the electrode body 20, the first sealing portion 70 is formed by joining the mutually facing surfaces of the laminated film 50. In this embodiment, in a predetermined portion including the first edge 50A and a predetermined portion including the second edge 50B of the laminated film 50, a heat-sealable resin layer is laminated on the surface opposite to the surface on which the insulating layer 53 of the second conductive barrier layer 52 is laminated. In another example, the first sealing portion 70 may be formed by joining the insulating layers 53 of the mutually facing surfaces of the laminated film 50. Note that the first sealing portion 70 may be formed by joining the first conductive barrier layer 51 or the second conductive barrier layer 52 of the mutually facing surfaces of the laminated film 50, for example, by welding.

[0058] The heat-sealable resin layer is joined to, for example, the second conductive barrier layer 52. The heat-sealable resin layer may be joined to the second conductive barrier layer 52 via an adhesive layer. The heat-sealable resin layer included in the laminated film 50 is a layer that imparts heat-sealing properties to the laminated film 50. Examples of the heat-sealable resin layer include resin films made of polyester-based resins such as polyethylene terephthalate-based resins and polybutylene terephthalate-based resins, polyolefin-based resins such as polyethylene-based resins and polypropylene-based resins, or acid-modified polyolefin-based resins obtained by graft-modifying these polyolefin-based resins with an acid such as maleic anhydride. From the viewpoints of sealing properties and strength, the thickness of the heat-sealable resin layer is preferably, for example, 20 to 300 μm, and more preferably 40 to 150 μm.

[0059] The first sealing part 70 is formed by heat-sealing the part including the first edge 50A of the laminated film 50 shown in FIG. 2 and the part including the second edge 50B. The first sealing part 70 extends in the longitudinal direction (FB direction) of the exterior body 40. In the exterior body 40, the position where the first sealing part 70 is formed can be arbitrarily selected. In the present embodiment, it is preferable that the base 70X of the first sealing part 70 is located on the side 43 at the boundary between the first surface 41 and the second surface 42 of the exterior body 40. The area of the first surface 41 is larger than that of the second surface 42. The base 70X of the first sealing part 70 may be located on any surface of the exterior body 40. In the present embodiment, in plan view, the first sealing part 70 protrudes outward from the electrode body 20. The first sealing part 70 may be folded, for example, toward the second surface 42 of the exterior body 40 or toward the first surface 41.

[0060] In the present embodiment, the second sealing part 80 is formed by joining the first conductive barrier layer 51 and the second conductive barrier layer 52 of the laminated film 50 and the film joining part 63 of the lid body 60.

[0061] <1-2. Manufacturing method of the power storage device> FIG. 5 is a flowchart showing an example of the manufacturing method of the power storage device 10. The manufacturing method of the power storage device 10 includes, for example, a first step, a second step, a third step, and a fourth step. The first step to the fourth step are, for example, carried out by a manufacturing apparatus for the power storage device 10. At least a part of the first step to the fourth step may be carried out by an operator. Note that the first step to the fourth step are for the sake of convenience in defining the names of the respective steps of the manufacturing method of the power storage device 10, and do not necessarily mean the order of the respective steps. The order of the first step to the fourth step can be arbitrarily changed as long as there is no technical contradiction.

[0062] In the first step of step S11, the manufacturing apparatus arranges the positive electrode lid body 60X on one side of the electrode body 20 in the FB direction and the negative electrode lid body 60Y on the other side. The manufacturing apparatus joins the current collector 30 with the positive electrode lid body 60X and the negative electrode lid body 60Y.

[0063] The second step of step S12 is carried out after the first step. In the second step, while restricting the movement of the electrode body 20 and the lid body 60 by the restricting means, the manufacturing apparatus winds the laminated film 50 around the electrode body 20 and the lid body 60 with tension acting on the laminated film 50. The restricting means is, for example, a groove into which the electrode body 20 and the lid body 60 are fitted. The restricting means may be a device that applies an external force to the electrode body 20 and the lid body 60 so that the electrode body 20 and the lid body 60 do not move. The restricting means may be a device that applies a force in the direction opposite to the direction in which the laminated film 50 is pulled to the electrode body 20 and the lid body 60. Note that the restricting means may include a roller that travels on the laminated film 50 in a state where the laminated film 50 is being pulled in order to remove wrinkles in the laminated film 50. The electrode body 20 may be housed inside the laminated film 50 configured in a cylindrical shape so that openings are formed at both ends in the FB direction, and after the current collector 30 and the lid body 60 are joined, the openings may be closed by the lid body 60. In yet another example, the electrode body 20 connected to the lid body 60 may be housed inside the laminated film 50 configured in a cylindrical shape so that openings are formed at both ends in the FB direction, and the openings may be closed by the lid body 60.

[0064] The third step of step S13 is carried out after the second step. In the second step, the manufacturing apparatus forms the second sealing portion 80 by welding the first conductive barrier layer 51 and the second conductive barrier layer 52 of the laminated film 50 and the film joint portion 63 of the lid body 60.

[0065] The fourth step of step S14 is performed before or after the third step. In the fourth step, the manufacturing apparatus heat-seals the heat-sealing resin layer of the portion including the first edge 50A of the laminated film 50 and the heat-sealing resin layer of the portion including the second edge 50B while restricting the movement of the electrode body 20 and the lid body 60 with tension acting on the laminated film 50, thereby forming the first sealing portion 70. In another example, the first sealing portion 70 may be formed by joining the insulating layers 53 on the facing surfaces of the laminated film 50 to each other. When the laminated film 50 does not have a heat-sealing resin layer, in the fourth step, the first sealing portion 70 is formed by joining the first conductive barrier layer 51 or the second conductive barrier layer 52 on the facing surfaces of the laminated film 50 to each other, for example, by welding.

[0066] <1-3. Operation and Effect of the Power Storage Device> In the power storage device 10, the first conductive barrier layer 51 and the positive electrode lid body 60X are directly joined. In the power storage device 10, the second conductive barrier layer 52 and the negative electrode lid body 60Y are directly joined. For this reason, the joining strength of the second sealing portion 80 is high. Further, the insulating layer 53 is laminated on the first conductive barrier layer 51 and the second conductive barrier layer 52 so that the first conductive barrier layer 51 and the second conductive barrier layer 52 do not conduct to each other. For this reason, the power storage device 10 has enhanced sealing performance, and conduction between the positive electrode lid body 60X and the negative electrode lid body 60Y is suppressed.

[0067] [2. Modification Example] The above embodiment is an example of a form that the power storage device, the exterior film, and the manufacturing method of the power storage device according to the present invention can take, and is not intended to limit the form. The power storage device, the exterior film, and the manufacturing method of the power storage device according to the present invention can take forms different from the forms exemplified in the embodiment. One example is a form in which a part of the configuration of the embodiment is replaced, changed, or omitted, or a new configuration is added to the embodiment. Some examples of modification examples of the embodiment are shown below. Note that the following modification examples can be combined with each other as long as there is no technical contradiction.

[0068] <2-1. First Modified Example> In the above embodiment, the laminated film 50 may not have the overlapping portion 50X. FIG. 6 is a cross-sectional view of the power storage device 10 of the first modified example. In the first modified example, one of the first conductive barrier layer 51 and the second conductive barrier layer 52 of the laminated film 50 is laminated at a location where the other of the insulating layers 53 is not laminated. In the example shown in FIG. 6, the insulating layer 53 includes a portion where neither the first conductive barrier layer 51 nor the second conductive barrier layer 52 is laminated.

[0069] <2-2. Second Modified Example> In the above embodiment, the first conductive barrier layer 51 and the second conductive barrier layer 52 may be laminated on the same surface of the insulating layer 53. FIG. 7 is a cross-sectional view of the power storage device 10 of the second modified example. In the second modified example, the first conductive barrier layer 51 and the second conductive barrier layer 52 are laminated on the surface of the insulating layer 53 opposite to the surface facing the electrode body 20. The first conductive barrier layer 51 and the second conductive barrier layer 52 are preferably laminated on the insulating layer 53 so that a gap is formed in the FB direction so as not to be electrically connected to each other. When the material constituting the insulating layer 53 does not have gas barrier properties, an arbitrary layer including a material having gas barrier properties may be laminated between the first conductive barrier layer 51 and the second conductive barrier layer 52 of the insulating layer 53. In the second modified example, the first conductive barrier layer 51 and the second conductive barrier layer 52 may be laminated on the surface of the insulating layer 53 facing the electrode body 20.

[0070] <2-3. Third Modified Example> In the above embodiment, the laminated film 50 may have an insulating layer 54 laminated on the surface opposite to the surface on which the insulating layer 53 of the second conductive barrier layer 52 is laminated. FIG. 8A is a cross-sectional view of the power storage device 10 of the third modification. In the third modification, the insulating layer 53 may be laminated up to the portion including the end 51X on the positive electrode lid body 60X side of the first conductive barrier layer 51. When welding the film joint portion 63 between the first conductive barrier layer 51 and the positive electrode lid body 60X, a part of the insulating layer 53 melts. For this reason, the insulating layer 53 is adjacent to the positive electrode joint portion 60XA which is the portion where the first conductive barrier layer 51 and the positive electrode lid body 60X are joined. In the third modification, a part of the insulating layer 53 melts by heat sealing, the first conductive barrier layer 51 and the positive electrode lid body 60X are adjacent, and the first conductive barrier layer 51 and the positive electrode lid body 60X may be joined by subsequent welding. Even in this case, the insulating layer 53 is adjacent to the positive electrode joint portion 60XA.

[0071] Similarly, the insulating layer 54 may be laminated up to the portion including the end 52Y on the negative electrode lid body 60Y side of the second conductive barrier layer 52. When welding the film joint portion 63 between the second conductive barrier layer 52 and the negative electrode lid body 60Y, a part of the insulating layer 54 melts. For this reason, the insulating layer 54 is adjacent to the negative electrode joint portion 60YA which is the portion where the second conductive barrier layer 52 and the negative electrode lid body 60Y are joined. In the third modification, a part of the insulating layer 54 melts by heat sealing, the second conductive barrier layer 52 and the negative electrode lid body 60Y are adjacent, and the second conductive barrier layer 52 and the negative electrode lid body 60Y may be joined by subsequent welding. Even in this case, the insulating layer 54 is adjacent to the negative electrode joint portion 60YA.

[0072] In the third modification, depending on the welding mode, at least one of the insulating layer 53 and the insulating layer 54 may not substantially melt. FIG. 8B is a cross-sectional view of the power storage device 10 of another example of the third modification. As shown in FIG. 8B, in the power storage device 10 of the third modification, the first conductive barrier layer 51 and the positive electrode lid 60X may be joined via the insulating layer 53. The second conductive barrier layer 52 and the negative electrode lid 60Y may be joined via the insulating layer 54. Even in the configuration shown in FIG. 8B, the joining strength of the second sealing portion 80 is higher than that of a power storage device that forms the second sealing portion by conventional heat sealing. When the first conductive barrier layer 51 is joined to the positive electrode lid 60X and the negative electrode lid 60Y via the insulating layer 53, even if the laminated film 50 does not have the second conductive barrier layer 52, the positive electrode lid 60X and the negative electrode lid 60Y do not conduct. However, since there is a possibility that the positive electrode lid 60X or the negative electrode lid 60Y may be short-circuited with the first conductive barrier layer 51, the laminated film 50 is provided with the second conductive barrier layer 52.

[0073] <2-4. Fourth Modification> In the first modification, the laminated film 50 may have an insulating layer 54 laminated on a surface opposite to the surface on which the insulating layer 53 of the second conductive barrier layer 52 is laminated. FIG. 9A is a cross-sectional view of the power storage device 10 of the fourth modification. In the fourth modification, the insulating layer 53 may be laminated up to a portion including the end portion 51X on the positive electrode lid 60X side of the first conductive barrier layer 51. When welding the first conductive barrier layer 51 and the film joining portion 63 of the positive electrode lid 60X, a part of the insulating layer 53 melts. Therefore, the insulating layer 53 is adjacent to the positive electrode joining portion 60XA which is the portion where the first conductive barrier layer 51 and the positive electrode lid 60X are joined. In the fourth modification, a part of the insulating layer 53 melts due to heat sealing, the first conductive barrier layer 51 and the positive electrode lid 60X are adjacent, and the first conductive barrier layer 51 and the positive electrode lid 60X may be joined by subsequent welding. Even in this case, the insulating layer 53 is adjacent to the positive electrode joining portion 60XA.

[0074] Similarly, the insulating layer 54 may be laminated up to a portion including the end portion 52Y on the negative electrode lid 60Y side of the second conductive barrier layer 52. When welding the second conductive barrier layer 52 and the film joint portion 63 of the negative electrode lid 60Y, a part of the insulating layer 54 melts. For this reason, the insulating layer 54 is adjacent to the negative electrode joint portion 60YA which is a portion where the second conductive barrier layer 52 and the negative electrode lid 60Y are joined. In the fourth modification, a part of the insulating layer 54 melts by heat sealing, the second conductive barrier layer 52 and the negative electrode lid 60Y are adjacent to each other, and the second conductive barrier layer 52 and the negative electrode lid 60Y may be joined by subsequent welding. Even in this case, the insulating layer 54 is adjacent to the negative electrode joint portion 60YA.

[0075] In the fourth modification, depending on the welding mode, at least one of the insulating layer 53 and the insulating layer 54 may not substantially melt. FIG. 9B is a cross-sectional view of the power storage device 10 of another example of the fourth modification. As shown in FIG. 9B, in the power storage device 10 of the fourth modification, the first conductive barrier layer 51 and the positive electrode lid 60X may be joined via the insulating layer 53. The second conductive barrier layer 52 and the negative electrode lid 60Y may be joined via the insulating layer 54. Even in the configuration shown in FIG. 9B, the joining strength of the second sealing portion 80 is higher than that of a power storage device forming the second sealing portion by conventional heat sealing. When the first conductive barrier layer 51, the positive electrode lid 60X, and the negative electrode lid 60Y are joined via the insulating layer 53, even if the laminated film 50 does not have the second conductive barrier layer 52, the positive electrode lid 60X and the negative electrode lid 60Y do not conduct. However, since there is a possibility that the positive electrode lid 60X or the negative electrode lid 60Y and the first conductive barrier layer 51 may be short-circuited, the laminated film 50 is provided with the second conductive barrier layer 52.

[0076] <2-5. Fifth Modification> In the second modification example, the insulating layer 53 may be laminated up to the portion including the end 51X on the positive electrode lid body 60X side of the first conductive barrier layer 51 and the portion including the end 52Y on the negative electrode lid body 60Y side of the second conductive barrier layer 52. FIG. 10A is a cross-sectional view of the power storage device 10 of the fifth modification example. When welding the first conductive barrier layer 51 and the film joint portion 63 of the positive electrode lid body 60X, a part of the insulating layer 53 melts. For this reason, the insulating layer 53 is adjacent to the positive electrode joint portion 60XA which is the portion where the first conductive barrier layer 51 and the positive electrode lid body 60X are joined. In the fifth modification example, a part of the insulating layer 53 melts by heat sealing, the first conductive barrier layer 51 and the positive electrode lid body 60X are adjacent, and the first conductive barrier layer 51 and the positive electrode lid body 60X may be joined by subsequent welding. Even in this case, the insulating layer 53 is adjacent to the positive electrode joint portion 60XA.

[0077] When welding the second conductive barrier layer 52 and the film joint portion 63 of the negative electrode lid body 60Y, a part of the insulating layer 53 melts. For this reason, the insulating layer 53 is adjacent to the negative electrode joint portion 60YA which is the portion where the second conductive barrier layer 52 and the negative electrode lid body 60Y are joined. In the fifth modification example, a part of the insulating layer 53 melts by heat sealing, the second conductive barrier layer 52 and the negative electrode lid body 60Y are adjacent, and the second conductive barrier layer 52 and the negative electrode lid body 60Y may be joined by subsequent welding. Even in this case, the insulating layer 53 is adjacent to the negative electrode joint portion 60YA.

[0078] In the fifth modification example, depending on the welding mode, at least one of the insulating layer 53 and the insulating layer 54 may not substantially melt. FIG. 10B is a cross-sectional view of the power storage device 10 of another example of the fifth modification example. As shown in FIG. 10B, in the power storage device 10 of the fifth modification example, the first conductive barrier layer 51 and the positive electrode lid 60X may be joined via the insulating layer 53. The second conductive barrier layer 52 and the negative electrode lid 60Y may be joined via the insulating layer 54. The joining strength of the second sealing portion 80 is higher than that of a power storage device that forms the second sealing portion by conventional heat sealing even in the configuration shown in FIG. 10B. When the first conductive barrier layer 51 is joined to the positive electrode lid 60X and the negative electrode lid 60Y via the insulating layer 53, the positive electrode lid 60X and the negative electrode lid 60Y do not conduct even if the laminated film 50 does not have the second conductive barrier layer 52. However, since there is a possibility that the positive electrode lid 60X or the negative electrode lid 60Y and the first conductive barrier layer 51 may be short-circuited, the laminated film 50 is provided with the second conductive barrier layer 52.

[0079] <2-6. Sixth modification example> In the above embodiment, the layer configuration of the laminated film 50 can be changed. FIG. 11 is a cross-sectional view showing an example of the layer configuration of the laminated film 50 included in the power storage device of the sixth modification example. The laminated film 50 may have an insulating layer 55 and an insulating layer 56. The insulating layer 55 is laminated on the surface of the first conductive barrier layer 51 opposite to the surface on which the insulating layer 53 is laminated. The insulating layer 56 is laminated on the surface of the second conductive barrier layer 52 opposite to the surface on which the insulating layer 53 is laminated.

[0080] In the FB direction, it is preferable that the end portion 51X of the first conductive barrier layer 51 on the positive electrode lid body 60X side is located closer to the positive electrode lid body 60X than the end portion 55X of the insulating layer 55 on the positive electrode lid body 60X side. Since the end portion 51X of the first conductive barrier layer 51 is exposed, the first conductive barrier layer 51 and the positive electrode lid body 60X can be easily joined. In the FB direction, it is preferable that the end portion 52Y of the second conductive barrier layer 52 on the negative electrode lid body 60Y side is located closer to the negative electrode lid body 60Y than the end portion 56Y of the insulating layer 56 on the negative electrode lid body 60Y side. Since the end portion 52Y of the second conductive barrier layer 52 is exposed, the second conductive barrier layer 52 and the negative electrode lid body 60Y can be easily joined.

[0081] <2-7. Seventh Modified Example> In the above embodiment, the power storage device 10 may further include an outer bag 100 that insulates the laminated film 50, the positive electrode lid body 60X, and the negative electrode lid body 60Y from the outside. FIG. 12 is a cross-sectional view of the power storage device 10 according to the seventh modified example. The outer bag 100 wraps at least the laminated film 50, the positive electrode lid body 60X, and the negative electrode lid body 60Y. The material constituting the outer bag 100 can be arbitrarily selected as long as it is an insulating material. As the material constituting the outer bag 100, for example, the materials exemplified as the material constituting the insulating layer 53 can be used. It is preferable that a hole 100X through which wiring or the like for connecting the external device and the lid body 60 can pass is formed at a position facing the second surface 62 of the lid body 60 in the outer bag 100.

[0082] <2-8. Eighth Modified Example> In the above embodiment, the lid body 60 was given as a specific example of the positive electrode member and the negative electrode member, but the specific examples of the positive electrode member and the negative electrode member are not limited to the lid body 60. FIG. 13 is a cross-sectional view of the power storage device 10 of the eighth modification. In the eighth modification, the positive electrode member and the negative electrode member are the electrode terminals 130A and 130B. The first conductive barrier layer 51 is joined to the electrode terminal 130A connected to the positive electrode. The second conductive barrier layer 52 is connected to the electrode terminal 130B connected to the negative electrode. In the eighth modification, in the laminated film 50, for example, a housing portion (depression) for housing the electrode body 20 may be formed by cold forming. The eighth modification can be similarly applied to the first to seventh modifications.

[0083] <2-9. Ninth Modification> In the above embodiment, the first conductive barrier layer 51 of the portion including the third edge 50C (see FIG. 2) of the laminated film 50 may be joined to the film joint portion 63 of the negative electrode lid body 60Y, for example, by welding. The second conductive barrier layer 52 of the portion including the fourth edge 50D (see FIG. 2) of the laminated film 50 may be joined to the film joint portion 63 of the positive electrode lid body 60X, for example, by welding. The ninth modification can be similarly applied to the first to eighth modifications.

[0084] <2-10. Tenth Modification> In the above embodiment, the laminated film 50 of the power storage device 10 may protrude outward beyond at least one of the positive electrode lid body 60X and the negative electrode lid body 60Y in the FB direction. By closing the portion of the laminated film 50 that protrudes outward beyond the lid body 60, the electrode body 20 is sealed. The portion of the laminated film 50 that protrudes beyond the lid body 60 may be folded like a gable-top type pouch or a brick type pouch. In the tenth modification, it is preferable that a convex portion for connecting to an external device is formed on the second surface 62 of the lid body 60. The length of the convex portion in the FB direction is preferably such that it is exposed from the portion of the laminated film 50 that protrudes outward beyond the lid body 60.

[0085] <2-11. Eleventh Modification> In the above-described embodiment, the outer shape of the exterior body 40 can be arbitrarily changed. The outer shape of the exterior body 40 may be a cylinder, a prism, or a cube.

Explanation of Reference Numerals

[0086] 10: Power storage device 20: Electrode body 40: Exterior body 50: Laminated film 51: First conductive barrier layer 52: Second conductive barrier layer 53: Insulating layer 60: Cover 60X: Positive electrode cover (positive electrode member) 60Y: Negative electrode cover (negative electrode member) 60XA: Positive electrode joint 60YA: Negative electrode joint 130A: Electrode terminal (positive electrode member) 130B: Electrode terminal (negative electrode member)

Claims

1. An electrode body, A laminated film that wraps the electrode body so as to seal the electrode body, A positive electrode member and a negative electrode member that are connected to the electrode body and are composed of a conductive material, The laminated film, A first conductive barrier layer, A second conductive barrier layer, An insulating layer laminated on the first conductive barrier layer and the second conductive barrier layer so that the first conductive barrier layer and the second conductive barrier layer do not conduct, The first conductive barrier layer is directly joined to the positive electrode member or joined to the positive electrode member through the insulating layer, The second conductive barrier layer is directly joined to the negative electrode member or joined to the negative electrode member through the insulating layer A power storage device.

2. The insulating layer is laminated between the first conductive barrier layer and the second conductive barrier layer in the lamination direction of the laminated film The power storage device according to claim 1.

3. The laminated film includes a portion where the first conductive barrier layer, the insulating layer, and the second conductive barrier layer overlap in a plan view The power storage device according to claim 2.

4. A space is formed between the first conductive barrier layer and the second conductive barrier layer The power storage device according to claim 1.

5. The first conductive barrier layer and the second conductive barrier layer are laminated on the same surface of the insulating layer The power storage device according to claim 4.

6. It has a positive electrode joint portion which is a portion where the first conductive barrier layer and the positive electrode member are directly joined, The insulating layer is adjacent to the positive electrode joint portion The power storage device according to any one of claims 1 to 5.

7. It has a negative electrode joint portion which is a portion where the second conductive barrier layer and the negative electrode member are directly joined, The insulating layer is adjacent to the negative electrode joint portion The power storage device according to any one of claims 1 to 5.

8. The material constituting the insulating layer includes an insulating filler The power storage device according to any one of claims 1 to 5.

9. The material constituting the insulating layer has gas barrier properties The power storage device according to any one of claims 1 to 5.

10. At least one of the positive electrode member and the negative electrode member is a lid body that seals the electrode body together with the laminated film The power storage device according to any one of claims 1 to 5.

11. At least one of the positive electrode member and the negative electrode member is an electrode terminal The power storage device according to any one of claims 1 to 5.

12. Further comprising an outer bag that wraps the laminated film, the positive electrode member, and the negative electrode member The power storage device according to any one of claims 1 to 5.

13. A laminated film that wraps an electrode body of a power storage device, The power storage device is Comprising a positive electrode member and a negative electrode member that are connected to the electrode body and composed of a conductive material, The laminated film is A first conductive barrier layer, A second conductive barrier layer, An insulating layer laminated on the first conductive barrier layer and the second conductive barrier layer so that the first conductive barrier layer and the second conductive barrier layer do not conduct, The first conductive barrier layer is directly joined to the positive electrode member or joined to the positive electrode member via the insulating layer, The second conductive barrier layer is directly joined to the negative electrode member or joined to the negative electrode member via the insulating layer Laminated film.

14. A method for manufacturing a power storage device, The power storage device is An electrode body, A laminated film that wraps the electrode body so as to seal the electrode body, Comprising a positive electrode member and a negative electrode member that are connected to the electrode body and composed of a conductive material, The laminated film is A first conductive barrier layer, A second conductive barrier layer, An insulating layer laminated on the first conductive barrier layer and the second conductive barrier layer so that the first conductive barrier layer and the second conductive barrier layer do not conduct, The first conductive barrier layer is directly joined to the positive electrode member or joined to the positive electrode member via the insulating layer, The second conductive barrier layer is directly joined to the negative electrode member or joined to the negative electrode member via the insulating layer, The method for manufacturing the power storage device is A step of joining the first conductive barrier layer and the positive electrode member directly or via the insulating layer, A step of joining the second conductive barrier layer and the negative electrode member directly or via the insulating layer, Method for manufacturing a power storage device.

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