Power storage module

Abstract

The invention provides a power storage module. The power storage module includes a plurality of electrode bodies and a case. The housing includes a bottom portion, a peripheral side wall portion, a cover portion, and at least one partition wall portion. The bottom portion is located on one side of the plurality of electrode bodies in the second direction. The partition wall portion is integrally formed with the bottom portion and the peripheral wall portion. The partition wall portion is located between the plurality of electrode bodies adjacent to each other. The bottom portion, the peripheral wall portion, and the lid portion each have a resin layer and a barrier layer. The resin layer is composed of a resin composition. The barrier layer is laminated on the resin layer. The barrier layer has lower moisture permeability than the resin layer.

Description

Technical Field

[0001] The present disclosure relates to a power storage module. Background Art

[0002] In the receiving portion of the battery case disclosed in Japanese Patent Gazette No. 2019-106372, the lower wall is integrated with multiple (e.g., 3, 4 or more) side walls to form a space inside, with an open surface opposite to the lower wall, and one or more (e.g., 2, 3, 4, 5 or more) partition walls are provided in the space. Thus, the receiving portion includes a plurality of battery section portions separated by one or more partition walls arranged in the space. The electrode assemblies can be accommodated separately in each battery section portion. Moreover, the above-mentioned battery case also includes a cover portion for sealing the open surface of the receiving portion. The receiving portion is a molded product of a composition comprising a base polymer and an inorganic moisture absorbent dispersed in the base polymer. Summary of the invention

[0003] Japanese Patent Publication No. 2019-106372 discloses a resin shell capable of accommodating multiple electrode bodies. However, since the shell is made of resin, it has higher moisture permeability than a metal shell. There is room for further improvement in reducing the moisture permeability of the shell.

[0004] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide a power storage module having a resin case with reduced moisture permeability.

[0005] The storage module based on the present disclosure comprises a plurality of electrode bodies and a shell. The plurality of electrode bodies are arranged along a first direction. The shell accommodates the plurality of electrode bodies. The shell comprises a bottom, a peripheral side wall portion, a cover portion and at least one partition wall portion. The bottom is located on one side of the plurality of electrode bodies in a second direction. The second direction is orthogonal to the first direction. The peripheral side wall portion rises from the outer peripheral end of the bottom along the second direction. The peripheral side wall portion surrounds the plurality of electrode bodies. The cover portion is located on the other side of the plurality of electrode bodies in the second direction. The partition wall portion is integrally formed with the bottom and the peripheral side wall portion. The partition wall portion is located between the plurality of electrode bodies adjacent to each other. The bottom, the peripheral side wall portion and the cover portion respectively have a resin layer and a barrier layer. The resin layer is composed of a resin composition. The barrier layer is stacked on the resin layer. The barrier layer has a lower moisture permeability than the resin layer.

[0006] According to the above structure, the resin layer and the barrier layer are respectively arranged on the bottom, the peripheral side wall and the cover. Thus, in the storage battery module, even when the shell is mainly composed of the resin layer, the moisture permeability of the shell can be reduced. Furthermore, a storage battery module with reduced moisture permeability of the resin shell can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when read in conjunction with the accompanying drawings.

[0008] Figure 1 It is a perspective view showing the power storage module according to the first embodiment.

[0009] Figure 2 This is an exploded perspective view of a part of the power storage module according to the first embodiment.

[0010] Figure 3 Observe along the direction of the arrow on line III-III Figure 1 A cross-sectional view of a power storage module.

[0011] Figure 4 Observe along the direction of the arrow on line IV-IV Figure 1 A cross-sectional view of a power storage module.

[0012] Figure 5 Observe along the direction of the arrow on line VV Figure 1 A cross-sectional view of an electrode body in a power storage module.

[0013] Fig. 6A and Figure 6B It is a cross-sectional view of a power storage module according to Embodiment 2.

[0014] Figure 7 It is a cross-sectional view of a power storage module according to Embodiment 3. DETAILED DESCRIPTION

[0015] The embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be noted that in the drawings referred to below, the same or equivalent components are denoted by the same reference numerals.

[0016] (Implementation Method 1)

[0017] Figure 1 It is a perspective view showing the power storage module according to the first embodiment. Figure 2 This is an exploded perspective view of a part of the power storage module according to the first embodiment. Figure 3 Observe along the direction of the arrow on line III-III Figure 1 A cross-sectional view of a power storage module. Figure 4 Observe along the direction of the arrow on line IV-IV Figure 1 A cross-sectional view of a power storage module.

[0018] like Figure 1~Figure 4 As shown, the storage module 1 of the first embodiment of the present disclosure includes a plurality of electrode bodies 100 and a shell 200. The plurality of electrode bodies 100 are arranged in parallel along a first direction D1. It should be noted that the second direction D2 described later is a direction orthogonal to the first direction D1, and the third direction D3 is a direction orthogonal to both the first direction D1 and the second direction D2. The shell 200 accommodates the plurality of electrode bodies 100.

[0019] In this embodiment, the plurality of electrode bodies 100 include a first electrode body 100A, a second electrode body 100B, and a third electrode body 100C. When viewed from the first electrode body 100A, the third electrode body 100C is located on the opposite side of the second electrode body 100B. The plurality of electrode bodies 100 may include four or more electrode bodies.

[0020] Figure 5 Observe along the direction of the arrow on line VV Figure 1 A cross-sectional view of an electrode body in a power storage module. Figure 5 As shown, each of the plurality of electrode bodies 100 includes a plurality of electrodes 110 and 120 and a separator 130. In the present embodiment, the electrode body 100 is an electrode body for a secondary battery such as a lithium ion secondary battery.

[0021] like Figure 5 As shown, the plurality of electrodes 110 and 120 are arranged in a row along the first direction D1. The plurality of electrodes 110 and 120 include a plurality of positive electrodes 110 and a plurality of negative electrodes 120.

[0022] Each positive electrode 110 is formed into a rectangular shape that is long in the third direction D3. Each positive electrode 110 includes a positive electrode collector foil 112 and a positive electrode active material layer 114 provided on both sides of the positive electrode collector foil 112. The positive electrode collector foil 112 includes a positive electrode tab 112p (see Figure 3 and Figure 4 ). The positive electrode tab 112p protrudes toward one side in the third direction D3.

[0023] Each negative electrode 120 is formed in a rectangular shape that is long in the third direction D3. Each negative electrode 120 includes a negative electrode collector foil 122 and a negative electrode active material layer 124 provided on both sides of the negative electrode collector foil 122. The negative electrode collector foil 122 includes a negative electrode tab 122n (see Figure 3 and Figure 4 ). The negative electrode tab 122n protrudes toward the other side in the third direction D3.

[0024] The separator 130 insulates the positive electrode 110 from the negative electrode 120. The separator 130 is made of an insulating material and has tiny gaps that allow ions to pass through. Figure 5 As shown, the partition 130 is formed in a zigzag shape.

[0025] The separator 130 has a rectangular shape before being formed into a zigzag shape. The separator 130 is formed into a zigzag shape and arranged between the electrodes 110 and 120. The separator 130 has a plurality of intervening portions 132a, a plurality of upper folded portions 132b, a plurality of lower folded portions 132c, and an outermost covering portion 132d.

[0026] Each intervening portion 132a is interposed between a pair of electrodes 110 and 120 adjacent to each other in one direction. That is, each intervening portion 132a has a function of insulating the positive electrode 110 and the negative electrode 120. Each intervening portion 132a is composed of a rectangular region.

[0027] Each upper folded portion 132b connects the upper end of one of the plurality of sandwiching portions 132a and the upper end of a sandwiching portion 132a adjacent to the one sandwiching portion 132a on one side in one direction. In the present embodiment, the upper folded portion 132b is disposed above the positive electrode 110.

[0028] Each lower folded portion 132c connects the lower end of one of the plurality of clamping portions 132a and the lower end of the clamping portion 132a adjacent to the one of the plurality of clamping portions 132a on the other side in one direction. In the present embodiment, the lower folded portion 132c is disposed below the negative electrode 120. In other words, the negative electrode 120 is disposed on the lower folded portion 132c.

[0029] The outermost covering portion 132d covers all the upper folded portions 132b and all the lower folded portions 132c. In more detail, the outermost covering portion 132d is wound around a central axis parallel to the third direction D3, while covering all the electrodes 110, 120, all the sandwiching portions 132a, all the upper folded portions 132b and all the lower folded portions 132c. The terminal 132e of the outermost covering portion 132d is set to a range that does not overlap with the positive electrode active material layer 114 and the negative electrode active material layer 124 in one direction. In the present embodiment, the terminal 132e of the outermost covering portion 132d is arranged below each electrode 110, 120. It should be noted that the peripheral surface and the bottom surface of the plurality of electrodes 110, 120 and the separator 130 may be coated with an insulating film or may not be coated with an insulating film. The peripheral surfaces and bottom surfaces of the plurality of electrodes 110 , 120 and the separator 130 may be directly in contact with the housing 200 .

[0030] like Figure 1~Figure 4 As shown, the housing 200 includes a bottom portion 210, a peripheral side wall portion 220, a cover portion 250, and at least one partition wall portion 260. The bottom portion 210, the peripheral side wall portion 220, and the cover portion 250 each include a resin layer R and a barrier layer B.

[0031] The resin layer R has electrical insulation properties. The resin layer R is composed of a resin composition. The barrier layer B is laminated on the resin layer R. The barrier layer B has lower moisture permeability than the resin layer R. The resin layer R and the barrier layer B will be described in detail later.

[0032] The bottom portion 210 is located at one side of the plurality of electrode bodies 100 in the second direction D2. The bottom portion 210 extends along the first direction D1 and the third direction D3. When viewed from the second direction D2, the bottom portion 210 has a rectangular shape.

[0033] The bottom portion 210 includes a first bottom resin layer 211 composed of a first resin composition as a resin layer R, a bottom barrier layer 212 as a barrier layer B, and a second bottom resin layer 213 composed of a third resin composition. The second resin composition will be described later.

[0034] The bottom barrier layer 212 is disposed outside the housing 200 when viewed from the first bottom resin layer 211. The bottom barrier layer 212 is disposed to entirely overlap the first bottom resin layer 211 when viewed from the second direction D2. The bottom barrier layer 212 is bonded to the first bottom resin layer 211 via the second bottom resin layer 213.

[0035] The second bottom resin layer 213 is bonded to the first bottom resin layer 211 by heat fusion. The second bottom resin layer 213 and the first bottom resin layer 211 may be fused together at the entire contact surface with each other, or may be fused together at a portion of the contact surface with each other. The second bottom resin layer 213 is fused only near the outer peripheral end of the first bottom resin layer 211 when viewed from the second direction D2.

[0036] The peripheral side wall portion 220 stands up from the outer peripheral end of the bottom portion 210 in the second direction D2. The peripheral side wall portion 220 surrounds the plurality of electrode bodies 100. The peripheral side wall portion 220 forms an opening OP facing the side opposite to the bottom portion 210 side.

[0037] The peripheral side wall portion 220 has a pair of first wall portions 230 and a pair of second wall portions 240. The pair of first wall portions 230 are arranged in parallel along the first direction D1. The pair of first wall portions 230 extend in the third direction D3. The pair of second wall portions 240 are arranged in parallel along the third direction D3. The pair of second wall portions 240 extend in the first direction D1.

[0038] The peripheral side wall portion 220 includes a first peripheral side resin layer 221 composed of a first resin composition as a resin layer R, a peripheral side barrier layer 222 as a barrier layer B, and a second peripheral side resin layer 223 composed of a second resin composition.

[0039] When viewed from the first peripheral resin layer 221, the peripheral barrier layer 222 is disposed outside the housing 200. When viewed from the first direction D1 and the third direction D3, the peripheral barrier layer 222 is disposed so as to overlap the first peripheral resin layer 221 as a whole. The peripheral barrier layer 222 is bonded to the first peripheral resin layer 221 via the second peripheral resin layer 223.

[0040] The second circumferential side resin layer 223 is joined to the first circumferential side resin layer 221 by heat fusion. The second circumferential side resin layer 223 and the first circumferential side resin layer 221 may fuse the entire contact surface with each other, or may fuse a portion of the contact surface with each other. For example, when viewed from the first direction D1, the second circumferential side resin layer 223 and the first circumferential side resin layer 221 may be heat fused to each other only near the respective circumferential ends of a pair of first wall portions 230. When viewed from the third direction D3, the second circumferential side resin layer 223 and the first circumferential side resin layer 221 may be heat fused to each other only near the respective circumferential ends of a pair of second wall portions 240.

[0041] The cover portion 250 is located on the other side of the plurality of electrode bodies 100 in the second direction D2. The cover portion 250 closes the opening OP. The cover portion 250 has a film-like outer shape, for example.

[0042] The cover portion 250 includes a cover resin layer 251 as a resin layer R and made of a fourth resin composition, and a cover barrier layer 252 as a barrier layer B.

[0043] The cover resin layer 251 is bonded to the first peripheral resin layer 221 by heat fusion or the like. The cover barrier layer 252 is arranged outside the housing 200 when viewed from the cover resin layer 251. The cover barrier layer 252 is bonded to the first peripheral resin layer 221 via the cover resin layer 251.

[0044] The partition wall portion 260 is located between the plurality of electrode bodies 100 adjacent to each other. The partition wall portion 260 divides the storage space S of the housing 200. The housing 200 of this embodiment has a plurality of partition wall portions 260. The plurality of partition wall portions 260 include a first partition wall portion 260A and a second partition wall portion 260B. The plurality of partition wall portions 260 may include three or more partition wall portions.

[0045] The first partition wall 260A forms a first section S1 and a second section S2 in the housing space S of the housing 200. The second partition wall 260B forms a first section S1 and a third section S3 in the housing space S. When viewed from the first section S1, the third section S3 is located on the opposite side of the second section S2.

[0046] Furthermore, the first electrode body 100A is contained in the first section S1. The second electrode body 100B is contained in the second section S2. The third electrode body 100C is contained in the third section. An electrolyte is injected into the containing space S (the first section S1, the second section S2, and the third section S3). It should be noted that the electrolyte is not shown in the figure. The method of injecting the electrolyte is not particularly limited. The electrolyte can be injected from the opening OP before the opening OP is closed by the cover 250.

[0047] The partition wall portion 260 is made of the first resin composition. The partition wall portion 260 is integrally formed with the bottom portion 210 and the peripheral side wall portion 220. Specifically, the first bottom resin layer 211, the first peripheral side resin layer 221, and the partition wall portion 260 are integrally formed with each other. The partition wall portion 260 and the cover resin layer 251 may be joined to each other by thermal fusion or may not be joined.

[0048] It should be noted that in this embodiment, as the above-mentioned "integrated molding" method, there can be listed a method of simultaneously forming and joining each component in one step by a well-known method such as injection molding, or a method of separately forming a plurality of components and then joining them to each other by a well-known joining method such as welding, soldering or bonding.

[0049] Here, in this embodiment, a first resin composition that can constitute the first base resin layer 211 , the first peripheral resin layer 221 , and the partition wall portion 260 will be described.

[0050] The first resin composition may include polycarbonate, polyethylene, polypropylene, polyethylene compound, polyamide, polyester, polyphenylene sulfide (PPS), polyphenylene oxide, polystyrene, polycyclic olefin copolymer, acrylonitrile-butadiene-styrene copolymer, liquid crystal polymer (LCP), fluorine resin, mixtures thereof, alloys thereof, or copolymers thereof as base polymers. The base polymer is not limited thereto.

[0051] The first resin composition may include polyolefin, liquid crystal polymer, or fluorine resin as a base polymer. Polyolefin may include high-density polyethylene (HDPE). High-density polyethylene, liquid crystal polymer, or fluorine resin has a relatively low water vapor permeability. Therefore, the housing 200 mainly composed of the resin composition containing them has a relatively high moisture permeability resistance.

[0052] The liquid crystal polymer may include a structural unit derived from a hydroxybenzoic acid oligomer. The liquid crystal polymer may include, in addition to the hydroxybenzoic acid oligomer, two or more selected from the group consisting of HNA (2,6-hydroxynaphthoic acid), TPA (terephthalic acid), IPA (isophthalic acid), HQ (hydroquinone), BP (biphenol), PET (polyethylene terephthalate) and PEN (polyethylene naphthalate), copolymerized with a hydroxybenzoic acid (HBA) oligomer.

[0053] As fluorine resin, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE) or their mixture or copolymer etc. can be listed. Fluorine resin is hydrophobic. Therefore, based on the gross weight of resin composition, resin composition can contain, for example, about 20 weight % or less, about 15 weight % or less, about 10 weight % or less, about 3 weight % to about 10 weight %, about 5 weight % to about 10 weight % of fluorine resin. In the case where the content of fluorine resin is within the above-mentioned range, it can be considered that the molded product consisting of the first resin composition has the effect of blocking moisture from the surface of the molded product in contact with the outside air.

[0054] From the viewpoint of suppressing water vapor transmission rate, the first resin composition may further contain an inorganic moisture absorbent or graphite. Furthermore, the resin composition may contain a known substance as a conventional moisture barrier substance in addition to graphite.

[0055] In the present embodiment, the bottom barrier layer 212 and the second bottom resin layer 213 , the peripheral barrier layer 222 and the second peripheral resin layer 223 , and the cover resin layer 251 and the cover barrier layer 252 are formed of so-called laminate films.

[0056] The bottom barrier layer 212, the peripheral barrier layer 222, and the cover barrier layer 252 are made of metal such as aluminum. In the present embodiment, from the viewpoint of formability, the thickness of each of the bottom barrier layer 212, the peripheral barrier layer 222, and the cover barrier layer 252 is preferably 100 μm or less.

[0057] The thickness of the second bottom resin layer 213, the second peripheral resin layer 223 and the cover resin layer 251 are thinner than the thickness of the first bottom resin layer 211 and the first peripheral resin layer 221. The thickness of the second bottom resin layer 213, the second peripheral resin layer 223 and the cover resin layer 251 may be, for example, 50 μm or less.

[0058] The specific composition of the third resin composition constituting the second bottom resin layer 213, the second resin composition constituting the second peripheral side resin layer 223, and the fourth resin composition constituting the cover resin layer 251 is not particularly limited. The base polymer contained in the second resin composition, the third resin composition, and the fourth resin composition is preferably the same as the base polymer contained in the first resin composition. Thus, it is easy to thermally fuse the second bottom resin layer 213, the second peripheral side resin layer 223, and the cover resin layer 251 to another resin layer of the housing 200 composed of the first resin composition. From the viewpoint of making thermal fusion easier, the base polymer of these compositions is also preferably polyethylene or polypropylene.

[0059] The storage module 1 of the first embodiment of the present disclosure includes a plurality of conductive components 300. Each conductive component 300 is arranged in parallel with a plurality of electrode bodies 100 in the third direction D3. Each conductive component 300 can electrically connect a plurality of electrode bodies 100 adjacent to each other in the first direction D1. The plurality of conductive components 300 are disposed so as to be exposed to the storage space S. The plurality of conductive components 300 are partially buried in the shell 200. The conductive components 300 are arranged in a manner not to contact each barrier layer. The conductive components 300 can be exposed to the outside of the shell 200.

[0060] The power storage module 1 of the first embodiment of the present disclosure further includes a plurality of current collecting components 400. The plurality of current collecting components 400 are located on both sides of each of the plurality of electrode bodies 100 in the third direction D3. Each current collecting component 400 is joined to the positive electrode tab 112p or the negative electrode tab 122n by welding. Each current collecting component 400 is also joined to the conductive component 300. Thus, the conductive component 300 is electrically connected to the electrode body 100. It should be noted that the positive electrode tab 112p or the negative electrode tab 122n can be directly connected to the conductive component 300 by welding.

[0061] As described above, in the power storage module 1 of the first embodiment of the present disclosure, the bottom 210, the peripheral wall 220 and the lid 250 each have a resin layer R and a barrier layer B. The resin layer R is composed of a resin composition. The barrier layer B is laminated on the resin layer R. The barrier layer B has lower moisture permeability than the resin layer R.

[0062] According to the above structure, the resin layer R and the barrier layer B are respectively arranged on the bottom 210, the peripheral side wall 220 and the cover 250. Therefore, in the power storage module 1, even when the case 200 is mainly composed of the resin layer R, the moisture permeability of the case 200 can be reduced. Therefore, the power storage module 1 with reduced moisture permeability of the resin case can be provided.

[0063] In addition, in Embodiment 1 of the present disclosure, the bottom portion 210 includes a first bottom resin layer 211 composed of a first resin composition as a resin layer R and a bottom barrier layer 212 as a barrier layer B. The peripheral side wall portion 220 includes a first peripheral side resin layer 221 composed of a first resin composition as a resin layer R and a peripheral side barrier layer 222 as a barrier layer B. The partition wall portion 260 is composed of the first resin composition. The first bottom resin layer 211, the first peripheral side resin layer 221, and the partition wall portion 260 are integrally formed with each other.

[0064] According to the above structure, the first bottom resin layer 211 , the first peripheral resin layer 221 , and the partition wall portion 260 are all made of the first resin composition and are integrally molded with each other, thereby reducing the manufacturing cost of the housing 200 .

[0065] In addition, in the first embodiment of the present disclosure, the peripheral wall portion 220 further includes a second peripheral resin layer 223 composed of a second resin composition. When viewed from the first peripheral resin layer 221, the peripheral barrier layer 222 is arranged outside the housing 200. The peripheral barrier layer 222 is bonded to the first peripheral resin layer 221 via the second peripheral resin layer 223.

[0066] According to the above structure, the peripheral barrier layer 222 can be easily arranged on the peripheral wall portion 220. For example, the resin sheet and the barrier sheet can be arranged as the second peripheral resin layer 223 and the peripheral barrier layer 222 by welding a laminated film including a resin sheet and a barrier sheet from the outside of the first peripheral resin layer 221.

[0067] In the first embodiment of the present disclosure, the bottom 210 further includes a second bottom resin layer 213 made of a third resin composition. The bottom barrier layer 212 is disposed outside the housing 200 when viewed from the first bottom resin layer 211. The bottom barrier layer 212 is bonded to the first bottom resin layer 211 via the second bottom resin layer 213.

[0068] With the above structure, bottom barrier layer 212 can be easily arranged on bottom 210. For example, a laminated film including a resin sheet and a barrier sheet can be welded from the outside of first bottom resin layer 211 to arrange the resin sheet and the barrier sheet as second bottom resin layer 213 and bottom barrier layer 212.

[0069] (Implementation Method 2)

[0070] The following describes a storage module according to a second embodiment of the present disclosure. In the storage module according to the second embodiment of the present disclosure, the structure of the peripheral side wall portion is mainly different from that of the storage module 1 according to the first embodiment of the present disclosure. Therefore, in the storage module according to the second embodiment of the present disclosure, the description of the same structure and effect as that of the first embodiment is omitted.

[0071] Fig. 6A This is a cross-sectional view of the power storage module according to the second embodiment as viewed from one direction. Figure 6B This is a cross-sectional view of the power storage module according to Embodiment 2 as viewed from another direction. Fig. 6A and Figure 6B In the Figure 3 and Figure 4 The cross section of the power storage module 1 according to the first embodiment shown is viewed in the same cross section, and the power storage module is illustrated.

[0072] like Fig. 6A and Figure 6B As shown, in the power storage module 1a of the second embodiment of the present disclosure, the peripheral barrier layer 222a is buried in the first peripheral resin layer 221a to avoid being exposed from the peripheral wall portion 220a. This makes it easy to ensure electrical insulation of the outer surface of the peripheral wall portion 220a.

[0073] The first peripheral resin layer 221a is formed, for example, by injection molding the second resin composition so as to surround the peripheral barrier layer 222a. In the present embodiment, the peripheral barrier layer 222a may be a plate-shaped member.

[0074] (Implementation 3)

[0075] The following describes a power storage module according to a third embodiment of the present disclosure. The power storage module according to the third embodiment of the present disclosure mainly differs from the power storage module 1a according to the second embodiment of the present disclosure in the structure of the bottom. Therefore, in the power storage module according to the third embodiment of the present disclosure, the description of the same structure and effects as those in the second embodiment is omitted.

[0076] Figure 7 is a cross-sectional view of a power storage module according to Embodiment 3. Figure 7 In Fig. 6A The cross section of the power storage module 1 a according to the second embodiment shown is viewed in the same cross section, and the power storage module is illustrated.

[0077] like Figure 7 As shown, in the power storage module 1b according to the third embodiment of the present disclosure, the bottom barrier layer 212b is buried in the first bottom resin layer 211b to avoid being exposed from the bottom 210b. This makes it easy to ensure electrical insulation of the outer surface of the bottom 210b.

[0078] The first bottom resin layer 211b is formed, for example, by injection molding the third resin composition so as to surround the bottom barrier layer 212b. In this embodiment, the bottom barrier layer 212b may be a plate-shaped member. Furthermore, the peripheral barrier layer 222b may extend upright from the outer peripheral end of the bottom barrier layer 212b when viewed from the second direction D2.

[0079] Although the embodiments of the present invention have been described, it should be considered that the embodiments disclosed this time are illustrative in all points and are not restrictive. The scope of the present invention is disclosed by the claims, and all modifications within the meaning and scope equivalent to the claims are included.

Claims

1. A power storage module comprising: A plurality of electrode bodies are arranged in parallel along a first direction; and a shell, accommodating the plurality of electrode bodies, The housing comprises: A bottom portion, located at one side of the plurality of electrode bodies in a second direction, the second direction being orthogonal to the first direction; A peripheral side wall portion, rising from the outer peripheral end of the bottom along the second direction, surrounding the plurality of electrode bodies; a cover portion located at the other side of the plurality of electrode bodies in the second direction; and At least one partition wall portion is formed integrally with the bottom portion and the peripheral side wall portion and is located between the plurality of electrode bodies adjacent to each other. The bottom portion, the peripheral side wall portion, and the cover portion each include a resin layer and a barrier layer. The resin layer is composed of a resin composition. The barrier layer is stacked on the resin layer and has a lower moisture permeability than the resin layer.

2. The power storage module according to claim 1, wherein: The bottom portion includes a first bottom resin layer as the resin layer and a bottom barrier layer as the barrier layer, wherein the first bottom resin layer is composed of a first resin composition. The peripheral side wall portion includes a first peripheral side resin layer as the resin layer and a peripheral side barrier layer as the barrier layer, wherein the first peripheral side resin layer is composed of the first resin composition. The partition wall portion is composed of the first resin composition, The first bottom resin layer, the first peripheral resin layer, and the partition wall portion are integrally formed with each other.

3. The power storage module according to claim 2, wherein: The peripheral side wall portion further includes a second peripheral side resin layer, wherein the second peripheral side resin layer is composed of a second resin composition. When viewed from the first peripheral resin layer, the peripheral barrier layer is arranged outside the housing. The peripheral barrier layer is bonded to the first peripheral resin layer via the second peripheral resin layer.

4. The power storage module according to claim 2, wherein: The peripheral barrier layer is buried in the first peripheral resin layer so as not to be exposed from the peripheral wall portion.

5. The power storage module according to any one of claims 2 to 4, wherein: The bottom further comprises a second bottom resin layer, wherein the second bottom resin layer is composed of a third resin composition. When viewed from the first bottom resin layer, the bottom barrier layer is arranged outside the housing, The bottom barrier layer is bonded to the first bottom resin layer via the second bottom resin layer.

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