Power storage device, lid unit, and method for manufacturing power storage device

Abstract

To provide a power storage device with high sealing performance, a lid unit used in the power storage device, and a method for manufacturing the power storage device.SOLUTION: A power storage device includes an electrode assembly and an exterior body that seals the electrode assembly. The exterior body includes an exterior film that wraps the electrode assembly, a lid body that contains a metal material and seals the electrode assembly together with the exterior film, a connector that connects the exterior film and the lid body, a lid sealing portion where the connector and the lid body are joined, and a film sealing portion where the connector and the exterior film are joined. In a plan view, the film sealing portion is formed at a position spaced from the lid sealing portion.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an electricity storage device, a lid unit, and a method for manufacturing an electricity storage device. [Background technology]

[0002] Patent Document 1 discloses an example of an electricity storage device. This electricity storage device includes an electrode assembly and an exterior body that seals the electrode assembly. The exterior body includes an exterior film that encases the electrode assembly and a lid body that is joined to the exterior film. The lid body is made of a material containing a metal material. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-123686 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned electricity storage device, when the exterior film and the lid are joined by heat sealing, heat from the heat seal may be absorbed by the lid, causing a poor joint between the exterior film and the lid. If a poor joint between the exterior film and the lid occurs, the hermeticity of the electricity storage device may be reduced.

[0005] An object of the present invention is to provide an electricity storage device with high sealing performance, a lid unit used in the electricity storage device, and a method for manufacturing the electricity storage device. [Means for solving the problem]

[0006] An energy storage device according to a first aspect of the present invention comprises an electrode body and an exterior body that seals the electrode body, wherein the exterior body has an exterior film that wraps the electrode body, a lid body that is composed of a metal material and seals the electrode body together with the exterior film, a connector that connects the exterior film and the lid body, a lid sealing portion at which the connector and the lid body are joined, and a film sealing portion at which the connector and the exterior film are joined, and in a planar view, the film sealing portion is formed at a position spaced apart from the lid sealing portion.

[0007] An electricity storage device according to a second aspect of the present invention is the electricity storage device according to the first aspect, wherein, in a plan view, the film sealing portion is formed at a position closer to the electrode body than the lid sealing portion.

[0008] An electricity storage device according to a third aspect of the present invention is the electricity storage device according to the first aspect, wherein, in a plan view, the film sealing portion is formed at a position farther from the electrode body than the lid sealing portion.

[0009] A lid unit according to a fourth aspect of the present invention is a lid unit used as an outer casing for an electricity storage device, and comprises a lid body comprising a metal material and a connector for connecting the lid body to an outer casing film that constitutes the outer casing, the connector being joined to the lid body.

[0010] An energy storage device according to a fifth aspect of the present invention comprises an electrode body and an exterior body that seals the electrode body, and the exterior body has an exterior film that wraps the electrode body, a lid body that contains a metal material and is joined to the exterior film, and a thermal conduction suppressor that is disposed between the exterior film and the lid body and is joined to the exterior film and the lid body.

[0011] An electricity storage device according to a sixth aspect of the present invention is the electricity storage device according to the fifth aspect, wherein the thermal conduction suppressing body is made of a material having a lower thermal conductivity than a metallic material included in a material constituting the lid.

[0012] An electricity accumulation device according to a seventh aspect of the present invention is the electricity accumulation device according to the fifth or sixth aspect, wherein the thermal conduction suppressing body is a resin molded product.

[0013] An electricity storage device according to an eighth aspect of the present invention is the electricity storage device according to any one of the fifth to seventh aspects, wherein the thermal conduction suppressing body includes a barrier layer.

[0014] A lid unit according to a ninth aspect of the present invention is a lid unit used as an exterior body for an electricity storage device, and includes a lid body containing a metal material, and a heat conduction suppressing body joined to the lid body.

[0015] A method for manufacturing an electricity storage device according to a tenth aspect of the present invention includes an electrode body, and an exterior body that seals the electrode body, the exterior body including an exterior film that wraps the electrode body, and a lid body that is configured to include a metal material and seals the electrode body together with the exterior film, a connector that connects the exterior film and the lid body, and a lid sealing portion in which the connector and the lid body are joined, The method for manufacturing an electricity storage device includes a film sealing portion in which the connector and the exterior film are joined, and the film sealing portion is formed at a position spaced apart from the lid sealing portion in a plan view. The method for manufacturing an electricity storage device includes a step of forming the lid sealing portion and a step of forming the film sealing portion.

[0016] A method for manufacturing an electricity storage device according to an eleventh aspect of the present invention is a method for manufacturing an electricity storage device including an electrode assembly and an exterior body sealing the electrode assembly, the exterior body having an exterior film wrapping the electrode assembly, a lid body including a metal material and joined to the exterior film, and a thermal conduction suppressor disposed between the exterior film and the lid body and joined to the exterior film and the lid body. The method for manufacturing an electricity storage device includes a step of joining the exterior film and the lid body in a state in which the thermal conduction suppressor is disposed between the exterior film and the lid body. Effect of the Invention

[0017] The electricity storage device, the lid unit, and the method for manufacturing the electricity storage device according to the present invention can contribute to improving the sealing performance of the electricity storage device. [Brief description of the drawings]

[0018] [Figure 1A] FIG. 1 is a perspective view of an electricity storage device according to an embodiment. [Figure 1B] 1B is a diagram showing a method for measuring the seal strength of a lid sealing portion of the electricity storage device in FIG. 1A. [Diagram 2] 1B is a cross-sectional view showing an example of a layer structure of an exterior film included in the electricity storage device of FIG. 1A. [Diagram 3] FIG. 1B is a diagram showing the state in which the exterior film of the power storage device of FIG. 1A is unfolded. [Figure 4] 1B is a perspective view of a lid provided in the electricity storage device of FIG. 1A. [Diagram 5] 1B is a cross-sectional view showing an example of a layer structure of a connector included in the electricity storage device of FIG. 1A. [Figure 6] 1B is a cross-sectional view taken along line D6-D6 in FIG. 1A. [Figure 7] 4 is a flowchart showing an example of a method for manufacturing the electricity storage device in FIG. 1A. [Figure 8] FIG. 8 is a diagram relating to the fourth step in FIG. 7. [Figure 9] FIG. 4 is a cross-sectional view of an electricity accumulation device according to a first modified example. [Figure 10] 10 is a diagram showing a fourth step of the method for manufacturing the electricity storage device in FIG. 9. [Figure 11] FIG. 11 is a cross-sectional view of an electricity accumulation device according to a second modified example. [Figure 12] 12 is a flowchart showing an example of a method for manufacturing the electricity storage device in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an electricity 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 "to" means "not less than" or "not more than." For example, the expression "2 to 15 mm" means 2 mm or more and 15 mm or less.

[0020] [1. Embodiment] <1-1. Configuration of the power storage device> FIG. 1A is a perspective view showing a schematic diagram of an electric storage device 10 according to an embodiment. FIG. 1B is a diagram showing a method for measuring the seal strength of the lid sealing portion of the electric storage device of FIG. 1A. FIG. 2 is a cross-sectional view showing an example of a layer structure of an exterior film 50 included in the electric storage device 10 of FIG. 1A. FIG. 3 is a diagram showing a state in which the exterior film 50 included in the electric storage device 10 of FIG. 1A is unfolded. FIG. 4A is a perspective view of a lid body 60 included in the electric storage device 10 of FIG. 1A. FIG. 5 is a cross-sectional view showing an example of a layer structure of a connection body 100 included in the electric storage device 10 of FIG. 1A. FIG. 6 is a cross-sectional view taken along line D6-D6 in FIG. 1A. In FIG. 1A, the arrow UD direction indicates the thickness direction of the electric storage device 10, the arrow LR direction indicates the width direction of the electric storage device 10, and the arrow FB direction indicates the depth direction of the electric storage device 10. The directions indicated by the arrows UDLRFB are common to the following figures.

[0021] The electricity storage device 10 includes an electrode body 20 including a current collector 30 (see FIG. 6 ) and an exterior body 40. The electrode body 20 includes electrodes (positive and negative electrodes) constituting an electricity storage member such as a lithium ion battery, a capacitor, an all-solid-state battery, a semi-solid battery, a quasi-solid battery, a polymer battery, an all-resin battery, a lead-acid battery, a nickel-metal hydride battery, a nickel-cadmium battery, a nickel-iron battery, a nickel-zinc battery, a silver oxide-zinc battery, a metal-air battery, a polyvalent cation battery, or a capacitor, and a separator. In this embodiment, the shape of the electrode body 20 is an approximately rectangular parallelepiped. Note that the term “approximately rectangular parallelepiped” includes, in addition to a perfect rectangular parallelepiped, a solid body 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.

[0022] The exterior body 40 seals the electrode body 20. The exterior body 40 includes an exterior film 50, a lid body 60, and a connection body 100. In this embodiment, the exterior film 50 is wrapped around the electrode body 20. The electrode body 20 may be housed inside the exterior film 50 that is configured in a cylindrical shape. The exterior body 40 has a pair of first surfaces 41A, 41B and a pair of second surfaces 42A, 42B. In this embodiment, the pair of first surfaces 41A, 41B are substantially the same size. In this embodiment, the pair of second surfaces 42A, 42B are substantially the same size. The pair of first surfaces 41A, 41B have a larger area than the pair of second surfaces 42A, 42B. The pair of lid bodies 60 are disposed on the sides of the electrode body 20, respectively.

[0023] For example, there is a method of forming a recess in the exterior film 50 through cold forming to accommodate the electrode body 20. However, it is not necessarily easy to form a deep recess by such a method. If an attempt is made to form a deep recess (for example, a forming depth of 15 mm) by cold forming, pinholes or cracks will occur in the exterior film 50, which is likely to cause a decrease in battery performance. On the other hand, the exterior body 40 seals the electrode body 20 by wrapping the exterior film 50 around the electrode body 20, so that the electrode body 20 can be easily sealed regardless of the thickness of the electrode body 20. In addition, in order to reduce the dead space between the electrode body 20 and the exterior film 50 to improve the volumetric energy density of the power storage device 10, it is preferable that the exterior film 50 is wrapped so as to contact the outer surface of the electrode body 20. In addition, in an all-solid-state battery, it is necessary to apply a high pressure uniformly from the outer surface of the battery to exhibit battery performance, so it is necessary to eliminate the space between the electrode body 20 and the exterior film 50, and therefore it is preferable that the exterior film 50 is wrapped so as to contact the outer surface of the electrode body 20.

[0024] As shown in FIG. 2, the exterior film 50 is a laminate (laminate film) having, for example, a base layer 51, a barrier layer 52, and a heat-sealable resin layer 53 in this order. The exterior film 50 does not need to include all of these layers, and may not include, for example, the barrier layer 52. That is, the exterior film 50 may be made of a material that is flexible and easy to bend, and may be made of, for example, a resin film. The exterior film 50 is preferably heat-sealable. The innermost layer and the outermost layer of the exterior film 50 may be the heat-sealable resin layer 53. In this case, the exterior film 50 may wrap the electrode body 20 and the lid body 60 by joining the outermost layer and the innermost layer.

[0025] The base layer 51 included in the exterior film 50 is a layer for imparting heat resistance to the exterior film 50 and suppressing the occurrence of pinholes that may occur during processing or distribution. The base layer 51 is configured to include at least one layer of a stretched polyester resin layer and a stretched polyamide resin layer. For example, the base layer 51 includes at least one layer of a stretched polyester resin layer and a stretched polyamide resin layer, so that the barrier layer 52 can be protected during processing of the exterior film 50 and breakage of the exterior film 50 can be suppressed. In addition, from the viewpoint of increasing the tensile elongation of the exterior film 50, the stretched polyester resin layer is preferably a biaxially stretched polyester resin layer, and the stretched polyamide resin layer is preferably a biaxially stretched polyamide resin layer. Furthermore, in terms of excellent puncture strength or impact strength, the stretched polyester resin layer is more preferably a biaxially stretched polyethylene terephthalate (PET) film, and the stretched polyamide resin layer is more preferably a biaxially stretched nylon (ONy) film. The base layer 51 may be configured to include both a stretched polyester resin layer and a stretched polyamide resin layer. The thickness of the base layer 51 is, for example, preferably 5 to 300 μm, and more preferably 5 to 150 μm, from the viewpoint of film strength.

[0026] The barrier layer 52 is a layer that at least prevents the intrusion of moisture. The barrier layer 52 is bonded to the base layer 51 via, for example, an adhesive layer 54. Examples of the barrier layer 52 include metal foil, vapor deposition film, and resin layer having barrier properties. Examples of the vapor deposition film include metal vapor deposition film, inorganic oxide vapor deposition film, and carbon-containing inorganic oxide vapor deposition film, and examples of the resin layer include fluorine-containing resins such as polyvinylidene chloride, polymers mainly composed of chlorotrifluoroethylene (CTFE), polymers mainly composed of tetrafluoroethylene (TFE), polymers having fluoroalkyl groups, and polymers mainly composed of fluoroalkyl units, and ethylene-vinyl alcohol copolymers. Examples of the barrier layer 52 include resin films having at least one of these vapor deposition films and resin layers. The barrier layer 52 may be provided in a plurality of layers. It is preferable that the barrier layer 52 includes a layer made of a metal material. Specific examples of the metal material constituting the barrier layer 52 include aluminum alloys, stainless steel, titanium steel, and steel plates. When used as a metal foil, it is preferable that the material contains at least one of an aluminum alloy foil and a stainless steel foil.

[0027] In the barrier layer 52, the layer made of the above-mentioned metal material may contain recycled metal material. Examples of recycled metal material include recycled aluminum alloy, stainless steel, titanium steel, or steel plate. These recycled materials can be obtained by known methods. The recycled aluminum alloy material can be obtained by the manufacturing method described in International Publication No. 2022 / 092231. The barrier layer 52 may be made of only recycled materials, or may be made of a mixed material of recycled materials and virgin materials. Note that recycled metal materials refer to metal materials that have been made reusable by collecting, isolating, and refining various products used in the city and waste from the manufacturing process. In addition, virgin metal materials refer to new metal materials refined from natural metal resources (raw materials) and are not recycled materials.

[0028] From the viewpoint of improving the formability of the exterior film 50, the aluminum alloy foil is preferably a soft aluminum alloy foil made of, for example, an annealed aluminum alloy, and from the viewpoint of further improving the formability, the aluminum alloy foil containing iron is preferable. In the aluminum alloy foil containing iron (100 mass%), the content of iron is preferably 0.1 to 9.0 mass%, more preferably 0.5 to 2.0 mass%. By having an iron content of 0.1 mass% or more, an exterior film 50 having better formability can be obtained. By having an iron content of 9.0 mass% or less, an exterior film 50 having better flexibility can be obtained. Examples of the soft aluminum alloy foil include aluminum alloy foils having a composition specified in JIS H4160:1994 A8021H-O, JIS H4160:1994 A8079H-O, JIS H4000:2014 A8021P-O, or JIS H4000:2014 A8079P-O. If necessary, silicon, magnesium, copper, manganese, etc. may be added. Softening can be achieved by annealing or the like.

[0029] Examples of the stainless steel foil include austenitic, ferritic, austenitic-ferritic, martensitic, and precipitation hardened stainless steel foils. From the viewpoint of providing an exterior film 50 with excellent formability, the stainless steel foil is preferably made of austenitic stainless steel.

[0030] Specific examples of the austenitic stainless steel constituting the stainless steel foil include SUS304, SUS301, and SUS316L, and among these, SUS304 is particularly preferred.

[0031] In the case of a metal foil, the thickness of the barrier layer 52 is sufficient as long as it at least functions as a barrier layer that prevents moisture from penetrating, and may be, for example, about 5 to 200 μm. The thickness of the barrier layer 52 is preferably about 85 μm or less, more preferably about 50 μm or less, even more preferably about 40 μm or less, and particularly preferably about 35 μm or less. The thickness of the barrier layer 52 is preferably about 10 μm or more, even more preferably about 20 μm or more, and more preferably about 25 μm or more. The preferred ranges of the thickness of the barrier layer 52 include about 10 to 85 μm, about 10 to 50 μm, about 10 to 40 μm, about 10 to 35 μm, about 20 to 85 μm, about 20 to 50 μm, about 20 to 40 μm, about 20 to 35 μm, about 25 to 85 μm, about 25 to 50 μm, about 25 to 40 μm, and about 25 to 35 μm. When the barrier layer 52 is made of an aluminum alloy foil, the above-mentioned range is particularly preferable. From the viewpoint of imparting high formability and high rigidity to the exterior film 50, the thickness of the barrier layer 52 is preferably about 35 μm or more, more preferably about 45 μm or more, even more preferably about 50 μm or more, and even more preferably about 55 μm or more, and is preferably about 200 μm or less, more preferably about 85 μm or less, even more preferably about 75 μm or less, and even more preferably about 70 μm or less. Preferable ranges are about 35 to 200 μm, about 35 to 85 μm, about 35 to 75 μm, about 35 to 70 μm, about 45 to 200 μm, about 45 to 85 μm, about 45 to 75 μm, about 45 to 70 μm, about 50 to 200 μm, about 50 to 85 μm, about 50 to 75 μm, about 50 to 70 μm, about 55 to 200 μm, about 55 to 85 μm, about 55 to 75 μm, and about 55 to 70 μm. When the exterior film 50 has high formability, deep drawing becomes easy, which can contribute to increasing the capacity of the electricity storage device. Furthermore, when the capacity of the electricity storage device is increased, the weight of the electricity storage device increases, but the rigidity of the exterior film 50 is increased, which can contribute to high sealing performance of the electricity storage device.In particular, when the barrier layer 52 is made of stainless steel foil, the thickness of the stainless steel foil is preferably about 60 μm or less, more preferably about 50 μm or less, even more preferably about 40 μm or less, even more preferably about 30 μm or less, and particularly preferably about 25 μm or less. The thickness of the stainless steel foil is preferably about 10 μm or more, more preferably about 15 μm or more. Preferred ranges for the thickness of the stainless steel foil include about 10 to 60 μm, about 10 to 50 μm, about 10 to 40 μm, about 10 to 30 μm, about 10 to 25 μm, about 15 to 60 μm, about 15 to 50 μm, about 15 to 40 μm, about 15 to 30 μm, and about 15 to 25 μm.

[0032] In addition, when the barrier layer 52 is an aluminum foil, it is preferable that at least the surface opposite to the base layer 51 is provided with a corrosion-resistant film in order to prevent dissolution and corrosion. The barrier layer 52 may be provided with a corrosion-resistant film on both sides. Here, the corrosion-resistant film refers to a thin film that is provided with corrosion resistance (e.g., acid resistance, alkali resistance, etc.) on the barrier layer 52 by performing, for example, hydrothermal conversion treatment such as boehmite treatment, chemical conversion treatment, anodizing treatment, plating treatment such as nickel or chromium, or corrosion prevention treatment by applying a coating agent on the surface of the barrier layer 52. Specifically, the corrosion-resistant film refers to a film that improves the acid resistance of the barrier layer 52 (acid-resistant film), a film that improves the alkali resistance of the barrier layer 52 (alkali-resistant film), etc. The treatment for forming the corrosion-resistant film may be one type, or two or more types may be combined. In addition, not only one layer but also multiple layers may be formed. Furthermore, among these treatments, hydrothermal conversion treatment and anodizing treatment are treatments in which the metal foil surface is dissolved by a treatment agent to form a metal compound with excellent corrosion resistance. Note that these treatments may also be included in the definition of chemical conversion treatment. In addition, when the barrier layer 52 has a corrosion-resistant coating, the corrosion-resistant coating is also included in the barrier layer 52.

[0033] The corrosion-resistant coating prevents delamination between the barrier layer 52 (e.g., aluminum alloy foil) and the base layer 51 during molding of the exterior film 50, prevents dissolution and corrosion of the surface of the barrier layer 52 due to hydrogen fluoride produced by a reaction between an electrolyte and moisture, and in particular prevents dissolution and corrosion of aluminum oxide present on the surface of the barrier layer 52 when the barrier layer 52 is an aluminum alloy foil, and also improves the adhesion (wettability) of the surface of the barrier layer 52, thereby preventing delamination between the base layer 51 and the barrier layer 52 during heat sealing and between the base layer 51 and the barrier layer 52 during molding.

[0034] The heat-sealable resin layer 53 is bonded to the barrier layer 52, for example, via an adhesive layer 55. The heat-sealable resin layer 53 included in the exterior film 50 is a layer that imparts heat-sealing sealability to the exterior film 50. Examples of the heat-sealable resin layer 53 include resin films made of polyester resins such as polyethylene terephthalate resins and polybutylene terephthalate resins, polyolefin resins such as polyethylene resins and polypropylene resins, or acid-modified polyolefin resins obtained by graft-modifying these polyolefin resins with an acid such as maleic anhydride. The thickness of the heat-sealable resin layer 53 is preferably, for example, 20 to 300 μm, and more preferably 40 to 150 μm, in terms of sealability and strength.

[0035] The exterior film 50 preferably has one or more layers having a buffer function (hereinafter referred to as "buffer layer") outside the heat-sealable resin layer 53, more preferably outside the barrier layer 52. The buffer layer may be laminated on the outside of the base material layer 51, or the base material layer 51 may also function as a buffer layer. When the exterior film 50 has multiple buffer layers, the multiple buffer layers may be adjacent to each other, or may be laminated via the base material layer 51, the barrier layer 52, etc.

[0036] The material constituting the buffer layer can be arbitrarily selected from materials having cushioning properties. The material having cushioning properties is, for example, rubber, nonwoven fabric, or foam sheet. The rubber is, for example, natural rubber, fluororubber, or silicone rubber. The rubber hardness is preferably about 20 to 90. The material constituting the nonwoven fabric is preferably a material having excellent heat resistance. When the buffer layer is made of nonwoven fabric, the lower limit of the thickness of the buffer layer is preferably 100 μm, more preferably 200 μm, and more preferably 1000 μm. When the buffer layer is made of nonwoven fabric, the upper limit of the thickness of the buffer layer is preferably 5000 μm, and more preferably 3000 μm. The thickness of the buffer layer is preferably in the range of 100 μm to 5000 μm, 100 μm to 3000 μm, 200 μm to 5000 μm, 200 μm to 3000 μm, 1000 μm to 5000 μm, or 1000 μm to 3000 μm. Among these, the thickness of the buffer layer is most preferably in the range of 1000 μm to 3000 μm.

[0037] When the buffer layer is made of rubber, the lower limit of the thickness of the buffer layer is preferably 0.5 mm. When the buffer layer is made of rubber, the upper limit of the thickness of the buffer layer is preferably 10 mm, more preferably 5 mm, and more preferably 2 mm. When the buffer layer is made of rubber, the preferred range of the thickness of the buffer layer is 0.5 mm to 10 mm, 0.5 mm to 5 mm, or 0.5 mm to 2 mm.

[0038] When the exterior film 50 has a buffer layer, the buffer layer functions as a cushion, thereby preventing the exterior film 50 from being damaged by impact when the electricity storage device 10 is dropped or by handling during production of the electricity storage device 10.

[0039] The lid body 60 shown in FIG. 4 has, for example, a rectangular parallelepiped shape and is made of a metal material. Here, "made of a metal material" means that the content of the metal 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, when the entire material constituting the lid body 60 is taken as 100% by mass. That is, the material constituting the lid body 60 can contain materials other than the metal material in addition to the metal material. The metal material constituting the lid body 60 can be selected arbitrarily. The metal material constituting the lid body 60 is, for example, aluminum, aluminum alloy, nickel, copper, or copper alloy. For example, when the electrode body 20 is a lithium ion battery, the lid body 60 connected to the positive electrode is preferably made of aluminum or an aluminum alloy. The lid body 60 connected to the negative electrode is preferably made of nickel, copper, or a copper alloy. The material constituting the lid body 60 connected to the negative electrode may be copper plated with nickel. The material constituting the lid body 60 may include recycled metal materials. In this embodiment, the lid 60 is made only of a metal material. Since the lid 60 contains a metal material, it also functions as an electrode terminal. This allows the configuration of the electricity storage device 10 to be simplified.

[0040] The lid body 60 has a first surface 61, a second surface 62, and a sealing surface 63. The first surface 61 faces the electrode body 20. The second surface 62 is the surface opposite to the first surface 61. For example, the lid body 60 may have an electrode terminal bonded to the second surface 62. At least a portion of the first surface 61 and the second surface 62 may be formed with projections and recesses. The sealing surface 63 is connected to the first surface 61 and the second surface 62, and is bonded to the lid bonding layer 130 (see FIG. 5) of the connection body 100.

[0041] The seal surface 63 includes a first seal surface 63A, a second seal surface 63B, a third seal surface 63C, and a fourth seal surface 63D. The first seal surface 63A constitutes the upper surface of the lid body 60. The first seal surface 63A extends in a first direction (LR direction in this embodiment) in a front view of the lid body 60. The second seal surface 63B and the third seal surface 63C are connected to the first seal surface 63A and constitute the side surface of the lid body 60. The second seal surface 63B and the third seal surface 63C extend in a second direction (UD direction in this embodiment) intersecting the first direction in a front view of the lid body 60. In this embodiment, the first direction and the second direction are orthogonal to each other in a front view of the lid body 60. The first direction and the second direction do not have to be orthogonal to each other in a front view of the lid body 60. The fourth seal surface 63D constitutes the lower surface of the lid body 60. The fourth sealing surface 63D extends in a first direction (the LR direction in this embodiment) when the lid 60 is viewed from the front.

[0042] When the lid body 60 is plate-shaped, it is preferable that the lid body 60 has a certain degree of thickness so that deformation of the exterior body 40 is suppressed even when the power storage device 10 is arranged in a stacked manner. From another viewpoint, when the lid body 60 is plate-shaped, it is preferable that the seal surface 63 of the lid body 60 has a certain degree of thickness so that the seal surface 63 of the lid body 60 and the connection body 100 can be suitably heat-sealed when forming the lid sealing portion 81 described later. The minimum value of the thickness of the lid body 60 is, for example, 1.0 mm, more preferably 3 mm, and further preferably 4 mm. The maximum value of the thickness of the lid body 60 is, for example, 10 mm, more preferably 8.0 mm, and further preferably 7.0 mm. The maximum value of the thickness of the lid body 60 may be 10 mm or more. The preferred ranges of thickness of the material constituting the lid body 60 are 1.0 mm to 10 mm, 1.0 mm to 8.0 mm, 1.0 mm to 7.0 mm, 3.0 mm to 10 mm, 3.0 mm to 8.0 mm, 3.0 mm to 7.0 mm, 4.0 mm to 10 mm, 4.0 mm to 8.0 mm, and 4.0 mm to 7.0 mm. The thickness of the lid body 60 may vary depending on the portion of the lid body 60. When the thickness of the lid body 60 varies depending on the portion, the thickness of the lid body 60 is the thickness of the thickest portion.

[0043] The cover 60 further includes boundaries 64, 65, 66, and 67. The boundary 64 is a boundary between the first seal surface 63A and the second seal surface 63B. The boundary 65 is a boundary between the first seal surface 63A and the third seal surface 63C. The boundary 66 is a boundary between the fourth seal surface 63D and the second seal surface 63B. The boundary 67 is a boundary between the fourth seal surface 63D and the third seal surface 63C. The boundaries 64 to 67 may have a corner shape, or may be rounded by performing R processing. In this embodiment, the boundaries 64 to 67 are corners.

[0044] The connecting body 100 connects the lid body 60 and the exterior film 50. The connecting body 100 is joined to at least a part of the sealing surface 63 of the lid body 60. In this embodiment, the connecting body 100 is joined to the entire sealing surface 63. At least a part of the portions of the connecting body 100 that are joined to the first sealing surface 63A, the second sealing surface 63B, the third sealing surface 63C, and the fourth sealing surface 63D may be divided or may be configured as an integral part.

[0045] The configuration of the connecting body 100 can be selected arbitrarily as long as it is a configuration that can connect the lid body 60 and the exterior film 50. In this embodiment, the connecting body 100 is a film. The connecting body 100 may be a resin molded product. In this embodiment, when the connecting body 100 is expressed as a resin molded product, this does not include a form in which the connecting body 100 is composed only of a film defined by the JIS (Japanese Industrial Standards) [Packaging Terminology] standard.

[0046] 5, the connection body 100 is, for example, a laminate (laminate film) having a thermally adhesive resin layer 110, a barrier layer 120, and a lid bonding layer 130 in this order. Note that the connection body 100 does not need to include all of these layers, and for example, may not include at least one of the barrier layer 120 and the lid bonding layer 130. When the connection body 100 does not have the lid bonding layer 130, the connection body 100 and the lid body 60 may be bonded to each other via, for example, an adhesive.

[0047] The heat-sealable resin layer 110 is joined to the heat-sealable resin layer 53 of the exterior film 50. The specifications of the heat-sealable resin layer 110 are the same as those of the heat-sealable resin layer 53.

[0048] The barrier layer 120 is bonded to the thermally adhesive resin layer 110 via, for example, an adhesive layer 140. The specifications of the barrier layer 120 are similar to those of the barrier layer 52.

[0049] The lid bonding layer 130 is bonded to the barrier layer 120, for example, via an adhesive layer 150. The lid bonding layer 130 is bonded to the sealing surface 63 of the lid 60. The material constituting the lid bonding layer 130 is appropriately selected according to the metal material constituting the lid 60. The material constituting the lid bonding layer 130 is preferably an acid-modified polyolefin resin graft-modified with an acid such as maleic anhydride.

[0050] The connecting body 100 is preferably adhesive. When the connecting body 100 is adhesive, the position of the connecting body 100 is not easily shifted relative to the lid body 60 when the lid sealing part 81 is formed with the connecting body 100 placed on the sealing surface 63 of the lid body 60. When the connecting body 100 is adhesive, the position of the exterior film 50 is not easily shifted relative to the connecting body 100 when the connecting body 100 and the exterior film 50 are heat-sealed to form the film sealing part 82. By incorporating a tackifier resin into at least one of the heat-sealable resin layer 110 and the lid bonding layer 130 of the connecting body 100, it is possible to impart tackiness to the connecting body 100. Examples of the tackifier resin include amorphous polyolefins. Examples of the amorphous polyolefins include amorphous polypropylene, and copolymers of amorphous propylene and other α-olefins. The content of the tackifier resin in the base material constituting the heat-sealable resin is preferably 10 to 20% by weight or less.

[0051] In this embodiment, with the exterior film 50 wrapped around the electrode body 20, the facing surfaces of the exterior film 50 (thermally adhesive resin layers 53) are heat sealed to form the first sealed portion 70.

[0052] The first sealed portion 70 is formed by heat-sealing a portion including the first edge 50A and a portion including the second edge 50B of the exterior film 50 shown in FIG. 3. The first sealed portion 70 extends in the longitudinal direction of the exterior body 40. The position at which the first sealed portion 70 is formed in the exterior body 40 can be selected arbitrarily. In this embodiment, the root 70X of the first sealed portion 70 is preferably located on the side 43 at the boundary between the first surface 41A and the second surface 42A of the exterior body 40. The root 70X of the first sealed portion 70 may be located on any surface of the exterior body 40. In this embodiment, the first sealed portion 70 protrudes outward from the electrode body 20 in a plan view. The first sealed portion 70 may be folded, for example, toward the second surface 42A of the exterior body 40, or toward the first surface 41A.

[0053] In this embodiment, the lid sealing portion 81 is formed by joining the lid bonding layer 130 of the connection body 100 and the sealing surface 63 of the lid body 60. Hereinafter, the seal strength between the lid bonding layer 130 of the connection body 100 and the sealing surface 63 of the lid body 60 may be referred to as the seal strength of the lid sealing portion 81. The seal strength of the lid sealing portion 81 is the seal strength between the heat-fusible resin layer 53 and the lid body 60 at the long side portion of the sealing surface 63, i.e., the seal strength between the heat-fusible resin layer 53 and the lid body 60 at the sealing surface 63 extending in the LR (width) direction in FIG. 1A.

[0054] The seal strength of the lid sealing portion 81 is measured as follows. First, a cut is made in a portion of the exterior film 50 that constitutes the first surface 41A of the exterior body 40, and three strip-shaped members 41X, 41Y, and 41Z (see the two-dot chain line in FIG. 1B) arranged in the LR direction are formed. The width of the three strip-shaped members 41X, 41Y, and 41Z in the LR direction is 15 mm. The ends of the strip-shaped members 41X, 41Y, and 41Z are joined to the lid body 60 at the lid sealing portion 81. The length of the lid body 60 in the LR direction is 45 mm or more. Next, the seal strength of each of the strip-shaped members 41X, 41Y, and 41Z is measured by pulling the end of each of the strip-shaped members 41X, 41Y, and 41Z opposite to the end joined to the lid body 60 upward in the UD direction (the direction opposite to the first surface 41B). In this embodiment, the seal strength of the lid sealing portion 81 is the average value of the seal strengths of the strip members 41X, 41Y, and 41Z. When the length of the lid body 60 in the LR direction is less than 45 mm, three strip members of an arbitrary width X mm less than 15 mm are formed, and the seal strengths of the three strip members are measured in the same manner as when the length of the lid body 60 in the LR direction is 45 mm or more. The obtained seal strengths are divided by the arbitrary width X mm and multiplied by 15 to convert them into the seal strengths of the three strip members in a width of 15 mm. The seal strength of the lid sealing portion 81 is the average value of the seal strengths of the three strip members converted into a width of 15 mm. Note that the seal strength of the lid sealing portion 81 when the lid body 60 is divided into multiple parts including long and short sides is the seal strength of the long side portion of the seal surface 63 of the multiple parts.

[0055] From the viewpoint of suitably maintaining the state in which the electrode body 20 is sealed by the exterior body 40, the seal strength of the lid sealing portion 81 is preferably 40N / 15mm or more, more preferably 50N / 15mm or more, more preferably 60N / 15mm or more, more preferably 70N / 15mm or more, and more preferably 85N / 15mm or more. When the seal strength of the lid sealing portion 81 is 40N / 15mm or more, the state in which the electrode body 20 is sealed by the exterior body 40 is suitably maintained even if the electricity storage device 10 is used for, for example, several years (less than 10 years). When the seal strength of the lid sealing portion 81 is 85N / 15mm or more, the state in which the electrode body 20 is sealed by the exterior body 40 is suitably maintained even if the electricity storage device 10 is used for, for example, 10 years or more. The seal strength of the lid sealing portion 81 is preferably 200N / 15mm or less. A preferred range for the seal strength of the lid sealing portion 81 is 40N / 15mm to 150N / 15mm, 50N / 15mm to 150N / 15mm, 60N / 15mm to 150N / 15mm, 70N / 15mm to 150N / 15mm, or 85N / 15mm to 150N / 15mm.

[0056] In this embodiment, the film sealing portion 82 is formed by joining the heat-sealing resin layer 110 of the connection body 100 and the heat-sealing resin layer 53 of the exterior film 50. In this embodiment, the film sealing portion 82 is formed by joining the heat-sealing resin layer 110 of the connection body 100 and the heat-sealing resin layer 53 of a portion including the third edge 50C and the fourth edge 50D (both see FIG. 3) of the exterior film 50. The film sealing portion 82 may be formed by joining the heat-sealing resin layer 110 of the connection body 100 and the heat-sealing resin layer 53 of a portion other than the portion including the third edge 50C and the fourth edge 50D of the exterior film 50.

[0057] In this embodiment, when forming the film sealing portion 82, in order to suppress the heat of the heat seal from being taken away by the lid body 60, the lid sealing portion 81 and the film sealing portion 82 are formed at positions spaced apart in the FB direction in a plan view of the electricity storage device 10. In this embodiment, the film sealing portion 82 is formed at a position closer to the electrode body 20 than the lid sealing portion 81 in the FB direction.

[0058] <1-2. Manufacturing method of electricity storage device> FIG. 7 is a flowchart showing an example of a method for manufacturing the power storage device 10. The method for manufacturing the power storage device 10 includes, for example, a first step, a second step, a third step, a fourth step, and a fifth step. The first step to the fifth step are performed, for example, by a manufacturing device for the power storage device 10. At least a part of the first step to the fifth step may be performed by an operator. Note that the first step to the fifth step are merely names of the steps in the method for manufacturing the power storage device 10 for the sake of convenience, and do not necessarily refer to the order of the steps. The order of the following steps can be changed as desired.

[0059] In the first step of step S1, the manufacturing equipment bonds the lid bonding layer 130 of the connecting body 100 to the sealing surface 63 of the lid body 60 to form the lid sealing portion 81. By completing the first step, the lid unit 60Z in which the connecting body 100 and the lid body 60 are bonded is completed.

[0060] The second step of step S2 is carried out before or after the first step. In the second step, the manufacturing device joins the first surface 61 of the lid body 60 to the end of the current collector 30. By completing the second step, the electrode body 20 and the lid body 60 are electrically connected to each other.

[0061] The third step of step S3 is performed after the second step. In the third step, the manufacturing device winds the exterior film 50 around the electrode body 20 and the connection body 100 while tension is applied to the exterior film 50, while restricting the movement of the electrode body 20 and the lid unit 60Z by the restricting means. The restricting means is, for example, a groove into which the electrode body 20 and the lid unit 60Z are fitted. The restricting means may be a device that applies an external force to the electrode body 20 and the lid unit 60Z so that the electrode body 20 and the lid unit 60Z do not move. The restricting means may be a device that applies a force to the electrode body 20 and the lid unit 60Z in the opposite direction to the direction in which the exterior film 50 is pulled. The restricting means may include a roller that runs on the exterior film 50 while the exterior film 50 is being pulled in order to remove wrinkles in the exterior film 50.

[0062] The fourth step of step S4 is performed after the third step. In the fourth step, the manufacturing device forms the film sealing portion 82 by heat-sealing the heat-fusible resin layer 53 of the exterior film 50 and the heat-fusible resin layer 110 of the connection body 100 together.

[0063] As shown in FIG. 8, in the fourth step, for example, a receiving jig 500 for the seal bar 400 is placed so as to contact the inner surface of the connecting body 100. In the fourth step, the exterior film 50 and the connecting body 100 are sandwiched between the seal bar 400 and the receiving jig 500 to form a film sealing portion 82. In the FB direction, the film sealing portion 82 is formed at a position separated from the lid sealing portion 81, so that the heat of the heat seal is not easily taken away by the lid body 60. Therefore, the time required for the fourth step can be shortened. After the fourth step is completed, the receiving jig 500 may be removed from the exterior body 40 or may remain placed inside the exterior body 40.

[0064] The fifth step of step S5 is performed before or after the fourth step. In the fifth step, the manufacturing apparatus forms the first sealing portion 70 by heat-sealing the heat-sealable resin layer 53 in a portion including the first edge 50A of the exterior film 50 and the heat-sealable resin layer 53 in a portion including the second edge 50B while restricting the movement of the electrode body 20 and the lid unit 60Z and applying tension to the exterior film 50.

[0065] <1-3. Actions and Effects of Electricity Storage Devices> In a plan view of the electricity storage device 10, the film sealing portion 82 is formed at a position separated from the lid sealing portion 81, and therefore, in the fourth step, heat from the heat seal is prevented from being taken away by the lid body 60. In the electricity storage device 10, the exterior film 50 and the connection body 100 are suitably joined at the film sealing portion 82, and therefore the electricity storage device 10 has high sealing performance.

[0066] [2. Modifications] The above-mentioned embodiments are examples of possible forms of the electricity storage device, lid unit, and manufacturing method of the electricity storage device according to the present invention, and are not intended to limit the forms. The electricity storage device, lid unit, and manufacturing method of the electricity storage device according to the present invention may take forms different from those exemplified in the embodiments. One example is a form in which a part of the configuration of the embodiment is replaced, changed, or omitted, or a form in which a new configuration is added to the embodiment. Below, some examples of modified embodiments are shown. Note that the following modified examples can be combined with each other as long as there is no technical contradiction.

[0067] <2-1. First modified example> In the above embodiment, the position where the film sealing portion 82 is formed can be selected arbitrarily as long as it is a position that does not overlap with the lid sealing portion 81 in a plan view of the electricity storage device 10. FIG. 9 is a cross-sectional view of the electricity storage device 10 of the first modified example. In the example shown in FIG. 9, the film sealing portion 82 is formed at a position farther from the electrode body 20 than the lid sealing portion 81 in the FB direction. As shown in FIG. 10, in the first modified example, in the fourth step, the film sealing portion 82 can be formed in a state where the seal bar 400 and the receiving jig 500 are disposed outside the exterior body 40. Therefore, in the first modified example, the fourth step can be easily performed.

[0068] <2-2. Second modified example> In the above embodiment, the connection body 100 may be omitted. Fig. 11 is a cross-sectional view of an electricity storage device 10 of a second modified example. The electricity storage device 10 has a second sealing portion 280. The second sealing portion 280 is a portion that is sealed by bonding the exterior film 50 and the lid body 60 via the thermal conduction-suppressing body 200.

[0069] The thermal conduction suppressing body 200 is an element that suppresses the loss of heat from the heat seal by the lid body 60 when the second sealing portion 280 is formed. In this embodiment, the thermal conduction suppressing body 200 has a main body portion 210 and a barrier layer 220. The thermal conduction suppressing body 200 does not necessarily have to have the barrier layer 220.

[0070] The main body 210 is joined to at least a part of the sealing surface 63 of the lid 60. From the viewpoint of suitably suppressing the loss of heat from the heat seal by the lid 60 when forming the second sealing portion 280, it is preferable that the main body 210 is joined to the entire sealing surface 63.

[0071] The material constituting the main body 210 can be selected arbitrarily as long as it is a material that can suppress the heat of the heat seal from being taken away by the lid 60 when forming the second sealing portion 280. The material constituting the main body 210 is preferably a material with a lower thermal conductivity than the metal material contained in the material constituting the lid 60.

[0072] The main body 210 may be a resin molded product that includes a resin material. Here, "includes a resin material" means that, when the entire material that constitutes the main body 210 is taken as 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. In other words, the material that constitutes the main body 210 can contain materials other than the resin material in addition to the resin material.

[0073] Specific examples of the resin include thermoplastic resins such as polyester, polyolefin, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, silicone resin, and phenol resin, and modified products of these resins. The resin material may be a mixture of these resins, a copolymer, or a modified product of the copolymer. Among these, the resin material is preferably a heat-fusible resin such as polyester or polyolefin, and more preferably polyolefin. When the resin material is a resin, the main body 210 may be molded by any molding method.

[0074] Specific examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, and copolymerized polyesters. Examples of copolymerized polyesters include copolymerized polyesters in which ethylene terephthalate is the main repeating unit. Specific examples of polyesters include copolymerized polyesters in which ethylene terephthalate is the main repeating unit and is polymerized with ethylene isophthalate (hereinafter abbreviated as polyethylene (terephthalate / isophthalate)), polyethylene (terephthalate / adipate), polyethylene (terephthalate / sodium sulfoisophthalate), polyethylene (terephthalate / sodium isophthalate), polyethylene (terephthalate / phenyl-dicarboxylate), and polyethylene (terephthalate / decane dicarboxylate). Of these, the resin material is preferably polybutylene terephthalate from the viewpoint of increasing heat resistance and pressure resistance.

[0075] Specific examples of polyolefins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; ethylene-α-olefin copolymers; polypropylenes such as homopolypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); propylene-α-olefin copolymers; and ethylene-butene-propylene terpolymers. When the polyolefin resin is a copolymer, it may be a block copolymer or a random copolymer. Among these, polypropylene is preferred as the resin material because it has excellent heat fusion properties and electrolyte resistance.

[0076] The resin as the resin material may contain a filler as necessary. Specific examples of the filler include glass beads, graphite, glass fiber, and carbon fiber. When the resin as the resin material contains the filler, the deformation resistance of the main body 210 against temperature changes can be improved. Note that when the main body 210 is expressed as a resin molded product, this does not include a mode in which the main body 210 is composed only of a film defined by the JIS (Japan Industrial Standards) [Packaging Terminology] standard.

[0077] From the viewpoint of suitably suppressing the heat of the heat seal from being taken by the lid 60 when the second sealing portion 280 is formed, it is preferable that the main body portion 210 has a certain degree of thickness in the UD direction. The minimum value of the thickness of the main body portion 210 is, for example, 0.5 mm, more preferably 3 mm, and further preferably 4 mm. The maximum value of the thickness of the main body portion 210 is, for example, 10 mm, more preferably 8.0 mm, and further preferably 7.0 mm. The maximum value of the thickness of the main body portion 210 may be 10 mm or more. The preferable ranges of the thickness of the material constituting the main body portion 210 are 0.5 mm to 10 mm, 0.5 mm to 8.0 mm, 0.5 mm to 7.0 mm, 3.0 mm to 10 mm, 3.0 mm to 8.0 mm, 3.0 mm to 7.0 mm, 4.0 mm to 10 mm, 4.0 mm to 8.0 mm, and 4.0 mm to 7.0 mm. The thickness of the main body portion 210 may vary depending on the part of the main body portion 210. When the thickness of main body portion 210 varies depending on the part, the thickness of main body portion 210 is the thickness of the thickest part.

[0078] The barrier layer 220 prevents moisture and the like from penetrating into the exterior body 40. The barrier layer 220 is preferably bonded to at least a portion of the portion of the main body 210 facing the outside of the exterior body 40 and the portion facing the heat-sealable resin layer 53 of the exterior film 50. The specifications of the barrier layer 220 are the same as the specifications of the barrier layer 52 of the exterior film 50. The barrier layer 220 may cover at least a portion of the lid 60 in addition to the main body 210.

[0079] FIG. 12 is a flowchart showing an example of a method for manufacturing the power storage device 10 of the second modified example. The method for manufacturing the power storage device 10 includes, for example, an eleventh step, a twelfth step, a thirteenth step, a fourteenth step, and a fifteenth step. The eleventh step to the fifteenth step are performed, for example, by a manufacturing device for the power storage device 10. At least a part of the eleventh step to the fifteenth step may be performed by an operator. Note that the eleventh step to the fifteenth step are merely names of the steps in the method for manufacturing the power storage device 10 of the second modified example, and do not necessarily indicate the order of the steps. The order of the following steps can be changed as desired.

[0080] In an eleventh process of step S11, the manufacturing equipment bonds the thermal conduction suppressing body 200 to the sealing surface 63 of the lid body 60. By completing the first process, the lid unit 260Z in which the thermal conduction suppressing body 200 and the lid body 60 are bonded together is completed.

[0081] The twelfth step of step S12 is performed before or after the eleventh step. In the twelfth step, the manufacturing equipment joins the first surface 61 of the lid body 60 to the end of the current collector 30. By completing the second step, the electrode body 20 and the lid body 60 are electrically connected to each other.

[0082] The thirteenth step of step S13 is performed after the twelfth step. In the thirteenth step, the manufacturing device winds the exterior film 50 around the electrode body 20 and the lid unit 260Z while tension is applied to the exterior film 50, while restricting the movement of the electrode body 20 and the lid unit 260Z by the restricting means. The restricting means is, for example, a groove into which the electrode body 20 and the lid unit 260Z are fitted. The restricting means may be a device that applies an external force to the electrode body 20 and the lid unit 260Z so that the electrode body 20 and the lid unit 260Z do not move. The restricting means may be a device that applies a force to the electrode body 20 and the lid unit 260Z in the opposite direction to the direction in which the exterior film 50 is pulled. The restricting means may include a roller that runs on the exterior film 50 while the exterior film 50 is being pulled in order to remove wrinkles in the exterior film 50.

[0083] The 14th step of step S14 is performed after the 13th step. In the 14th step, the manufacturing apparatus forms the second sealed portion 280 by heat-sealing the heat-fusible resin layer 53 of the exterior film 50 and the heat-conduction suppressing body 200 with the heat-conduction suppressing body 200 disposed between the exterior film 50 and the lid 60.

[0084] The 15th step of step S15 is performed before or after the 14th step. In the 15th step, the manufacturing apparatus forms the first sealing portion 70 by heat-sealing the heat-sealable resin layer 53 in a portion including the first edge 50A of the exterior film 50 and the heat-sealable resin layer 53 in a portion including the second edge 50B while restricting the movement of the electrode body 20 and the lid unit 260Z and applying tension to the exterior film 50.

[0085] <2-3.Third modified example> In the above embodiment, the exterior film 50 of the electricity storage device 10 may protrude outward beyond one of the two lid bodies 60 in the FB direction. The electrode body 20 is sealed by closing the portion of the exterior film 50 that protrudes outward beyond the lid body 60. The portion of the exterior film 50 that protrudes beyond the lid body 60 may be folded inward so that the outer surfaces of the exterior films 50 come into contact with each other, as in a Goebel-top container, or may be folded toward any surface of the exterior body 40, as in a brick container.

[0086] <2-4. Fourth modified example> In the above embodiment, the exterior body 40 may not have one of the two lid bodies 60. In this modification, in the FB direction, in a portion of the exterior body 40 where the lid body 60 is omitted, the electrode body 20 is sealed by closing a portion of the exterior film 50 that protrudes outward beyond the electrode body 20. The portion of the exterior film 50 that protrudes outward beyond the electrode body 20 may be folded like a Goebel-top container or a brick container, as in the seventh modification.

[0087] <2-5. Fifth Modification> In the above embodiment, it is possible to arbitrarily change the outer shape of the exterior body 40. The outer shape of the exterior body 40 may be a cylinder, a prism, or a cube.

[0088] <2-6. Sixth Modification> In the above embodiment, the electrode body 20 is wrapped in one exterior film 50, but it may be wrapped in two or more exterior films 50. [Explanation of symbols]

[0089] 10: Energy storage device 20: Electrode body 40: Exterior body 50: Exterior film 53: Barrier layer 60: Lid 60Z, 260Z: Lid unit 81: Lid sealing part 82: Film sealing section 100: Connector 200: Heat conduction suppressor 220: Barrier layer 280: Second sealing part

Claims

1. An electrode body; and an exterior body that seals the electrode body, The exterior body is An exterior film that wraps the electrode body; A lid body including a metal material and configured to seal the electrode body together with the exterior film; a connector that connects the exterior film and the lid; a lid sealing portion in which the connector and the lid are joined; a film sealing portion in which the connection body and the exterior film are joined, In a plan view, the film sealing portion is formed at a position spaced apart from the lid sealing portion. Energy storage device.

2. In a plan view, the film sealing portion is formed at a position closer to the electrode body than the lid sealing portion. The power storage device according to claim 1 .

3. In a plan view, the film sealing portion is formed at a position farther from the electrode body than the lid sealing portion. The power storage device according to claim 1 .

4. A lid unit used as an exterior body for an electricity storage device, A lid body including a metal material; a connector for connecting the lid and an exterior film constituting the exterior body, The connector is joined to the lid. Lid unit.

5. An electrode body; and an exterior body that seals the electrode body, The exterior body is An exterior film that wraps the electrode body; A lid body including a metal material and joined to the exterior film; a heat conduction suppressing body that is disposed between the exterior film and the lid and is joined to the exterior film and the lid. Energy storage device.

6. The heat conduction suppressing body is made of a material having a lower thermal conductivity than a metal material contained in the material constituting the lid. The electricity storage device according to claim 5 .

7. The thermal conduction suppressor is a resin molded product. The electricity storage device according to claim 5 or 6.

8. The thermal conduction suppressor includes a barrier layer. The electricity storage device according to claim 5 or 6.

9. A lid unit used as an exterior body for an electricity storage device, A lid body including a metal material; a heat conduction suppressing body joined to the lid body. Lid unit.

10. A method for manufacturing an electricity storage device, comprising: The power storage device is An electrode body; and an exterior body that seals the electrode body, The exterior body is An exterior film that wraps the electrode body; A lid body including a metal material and configured to seal the electrode body together with the exterior film; a connector that connects the exterior film and the lid; a lid sealing portion in which the connector and the lid are joined; a film sealing portion in which the connection body and the exterior film are joined, In a plan view, the film sealing portion is formed at a position spaced apart from the lid sealing portion, The method for manufacturing the electricity storage device includes: forming the lid sealing portion; forming the film sealing portion. A method for manufacturing an electricity storage device.

11. A method for manufacturing an electricity storage device, comprising: The power storage device is An electrode body; and an exterior body that seals the electrode body, The exterior body is An exterior film that wraps the electrode body; A lid body including a metal material and joined to the exterior film; a heat conduction suppressing body that is disposed between the exterior film and the lid and is joined to the exterior film and the lid, The method for manufacturing the electricity storage device includes: and joining the exterior film and the lid body with the thermal conduction suppressing body disposed between the exterior film and the lid body. A method for manufacturing an electricity storage device.

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