Power storage module

Abstract

To provide a power storage module suppressing reduction in holding force of an electrode body while increasing the accommodation space of a case.SOLUTION: In a power storage module 1 based on the present disclosure, a case 200 includes a case body 210 and at least one partition portion 220. The case body 210 has electrical insulation and surrounds the plurality of electrode bodies 100. The partition portion 220 has electrical insulation and is located between the electrode bodies 100 adjacent to each other to partition an accommodation space S of the case body 210. The partition portion 220 has a base 221, and a first projection 222. The base 221 is plate-shaped, and extends along a plane direction orthogonal to a first direction D1. The first projection 222 projects from the base 221 to one side in the first direction D1, and is in contact with one of the electrode bodies 100.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an energy storage module. [Background technology]

[0002] The storage section of the battery case disclosed in Patent Document 1 (JP 2019-106372 A) has a lower wall and a plurality of (e.g., three, four, or more) side walls integrated together to form a space therein, has an open surface facing the lower wall, and is provided with one or more (e.g., two, three, four, five, or more) partition walls within the space. As a result, the storage section includes a plurality of battery compartments separated by one or more partition walls disposed within the space. Each battery compartment can accommodate an electrode assembly. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-106372 A Summary of the Invention [Problem to be solved by the invention]

[0004] In order to improve the energy density of the energy storage module, it is preferable that the storage space inside the battery case is large. In the battery case disclosed in Patent Document 1, in order to increase the storage space inside the case, it is possible to make the partition wall thinner. However, if the partition wall is made thinner, the partition wall is more likely to be deformed by pressure from the electrode body. In other words, if the partition wall is made thinner, the holding force of the electrode body may decrease.

[0005] The present disclosure has been made in consideration of the above problems, and aims to provide an energy storage module that can increase the storage space of the case while suppressing a decrease in the holding force of the electrode body. [Means for solving the problem]

[0006] The energy storage module according to the present disclosure includes a plurality of electrode bodies and a case. The plurality of electrode bodies are arranged in a first direction. The case houses the plurality of electrode bodies. The case has a case body and at least one partition wall. The case body has electrical insulation and surrounds the plurality of electrode bodies. The partition wall has electrical insulation and is located between the plurality of adjacent electrode bodies to divide the housing space of the case body. The partition wall has a base and a first protruding portion. The base is plate-shaped and extends along a planar direction perpendicular to the first direction. The first protruding portion protrudes from the base to one side in the first direction and contacts one of the plurality of electrode bodies.

[0007] According to the above configuration, the storage space of the case can be enlarged by making the base relatively thin. Meanwhile, the thickness of the partition wall is relatively thick in the portion formed by the first protrusion and the base. Therefore, by configuring the first protrusion and the electrode body to contact each other, it is possible to suppress a decrease in the holding force of the electrode body in the storage space of the case. Effect of the Invention

[0008] According to the present disclosure, it is possible to increase the storage space of the case while suppressing a decrease in the holding force of the electrode body. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing an electricity storage module according to a first embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of a part of the electricity storage module according to the first embodiment. [Diagram 3] 3 is a cross-sectional view of the electricity storage module of FIG. 1, taken along the line III-III. [Figure 4] 4 is a cross-sectional view of the electricity storage module of FIG. 1 as viewed in the direction of the arrows IV-IV. [Diagram 5] 2 is a cross-sectional view of an electrode body accommodated in the electricity storage module of FIG. 1, as viewed in the direction of the VV line arrow. [Figure 6] 6 is a partial cross-sectional view of a part of the power storage module of FIG. 2, taken along the line VI-VI. [Figure 7] 5A to 5C are partial cross-sectional views of electricity storage modules according to respective modifications of the first embodiment. [Figure 8] FIG. 11 is an exploded perspective view showing a part of the electricity storage module according to the second embodiment. [Figure 9] FIG. 11 is an exploded perspective view showing a part of the electricity storage module according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0011] (Embodiment 1) Fig. 1 is a perspective view showing an electricity storage module according to embodiment 1. Fig. 2 is an exploded perspective view in which the electricity storage module according to embodiment 1 is partially disassembled. Fig. 3 is a cross-sectional view of the electricity storage module of Fig. 1 as viewed in the direction of the arrows III-III. Fig. 4 is a cross-sectional view of the electricity storage module of Fig. 1 as viewed in the direction of the arrows IV-IV.

[0012] As shown in FIGS. 1 to 4, the energy storage module 1 according to the first embodiment of the present disclosure includes a plurality of electrode bodies 100, a case 200, at least one connecting conductive member 310, and an external conductive member 320. The plurality of electrode bodies 100 are arranged in a first direction D1. The case 200 accommodates the plurality of electrode bodies 100. The connecting conductive member 310 is arranged in a third direction D3 and electrically connects the plurality of electrode bodies 100 adjacent to each other. The third direction D3 is perpendicular to the first direction D1. A second direction D2 described later is perpendicular to both the first direction D1 and the third direction D3.

[0013] In this embodiment, the multiple electrode assemblies 100 include a first electrode assembly 100A, a second electrode assembly 100B, and a third electrode assembly 100C. The third electrode assembly 100C is located opposite the second electrode assembly 100B as viewed from the first electrode assembly 100A. In this embodiment, the second electrode assembly 100B is located at the end of the multiple electrode assemblies 100 in the first direction D1. The third electrode assembly 100C is located at the end of the multiple electrode assemblies 100 on the opposite side to the second electrode assembly 100B in the first direction D1. The multiple electrode assemblies 100 may include four or more electrode assemblies.

[0014] Fig. 5 is a cross-sectional view of an electrode assembly housed in the power storage module of Fig. 1, viewed in the direction of the VV arrows. As shown in Fig. 5, each of the multiple electrode assemblies 100 includes multiple electrodes 110, 120 and a separator 130. In this embodiment, the electrode assembly 100 is an electrode assembly for a secondary battery, such as a lithium ion secondary battery.

[0015] 5, the multiple electrodes 110, 120 are arranged to line up in a first direction D1. The multiple electrodes 110, 120 include multiple positive electrodes 110 and multiple negative electrodes 120.

[0016] Each positive electrode 110 is formed in a rectangular shape that is long in the third direction D3 (a direction perpendicular to the paper surface in FIG. 5). Each positive electrode 110 has a positive electrode current collector foil 112 and a positive electrode active material layer 114 provided on both sides of the positive electrode current collector foil 112. The positive electrode current collector foil 112 has a positive electrode tab 112p (see FIGS. 3 and 4) on which the positive electrode active material layer 114 is not provided. The positive electrode tab 112p protrudes toward one side in the third direction D3.

[0017] Each negative electrode 120 is formed in a rectangular shape that is long in the third direction D3. Each negative electrode 120 has a negative electrode current collector foil 122 and a negative electrode active material layer 124 provided on both sides of the negative electrode current collector foil 122. The negative electrode current collector foil 122 has a negative electrode tab 122n (see FIGS. 3 and 4) on which the negative electrode active material layer 124 is not provided. The negative electrode tab 122n protrudes toward the other side in the third direction D3.

[0018] The separator 130 provides insulation between the positive electrode 110 and the negative electrode 120. The separator 130 is made of an insulating material and has minute voids that allow ions to pass through. As shown in Fig. 5, the separator 130 is formed in a zigzag shape.

[0019] The separator 130 has a rectangular shape before being folded in a zigzag shape. The separator 130 is disposed between the electrodes 110, 120 while being folded in a zigzag shape. The separator 130 has a plurality of interposed portions 132a, a plurality of upper folded portions 132b, a plurality of lower folded portions 132c, and an outermost covering portion 132d.

[0020] Each interposed portion 132a is interposed between a pair of electrodes 110, 120 adjacent to each other in one direction. That is, each interposed portion 132a has a function of insulating between the positive electrode 110 and the negative electrode 120. Each interposed portion 132a is formed of a rectangular region.

[0021] Each upper folded portion 132b connects an upper end portion of one of the plurality of intermediate portions 132a to an upper end portion of the intermediate portion 132a adjacent to the one intermediate portion 132a on one side in one direction among the plurality of intermediate portions 132a. In this embodiment, the upper folded portion 132b is disposed above the positive electrode 110.

[0022] Each lower folded portion 132c connects a lower end of one of the plurality of intermediate portions 132a to a lower end of another intermediate portion 132a adjacent to the one intermediate portion on the other side in one direction among the plurality of intermediate portions 132a. In this 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.

[0023] The outermost covering portion 132d covers each of the upper folded portions 132b and each of the lower folded portions 132c collectively. More specifically, the outermost covering portion 132d covers all of the electrodes 110, 120, all of the intervening portions 132a, all of the upper folded portions 132b, and all of the lower folded portions 132c collectively while being wound around a central axis parallel to the third direction D3. The end 132e of the outermost covering portion 132d is set in 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 this embodiment, the end 132e of the outermost covering portion 132d is provided below each of the electrodes 110, 120. The peripheral surfaces and bottom surfaces of the multiple electrodes 110, 120 and the separator 130 may or may not be covered with an insulating film. The peripheral and bottom surfaces of the multiple electrodes 110 , 120 and the separator 130 may be in direct contact with the case 200 .

[0024] Fig. 6 is a partial cross-sectional view of a part of the energy storage module of Fig. 2 as viewed in the direction of the arrows VI-VI. As shown in Figs. 1 to 4 and 6, the case 200 has a case main body 210 and at least one partition wall portion 220.

[0025] The case body 210 has electrical insulation properties at least on the surface facing the electrode body 100. The case body 210 surrounds the multiple electrode bodies 100.

[0026] The case body 210 has a bottom wall portion 211 , a peripheral side wall portion 212 , a hole portion 215 , a lid 216 , and a welded portion 217 .

[0027] The bottom wall portion 211 is made of a resin composition. In the case body 210, the bottom wall portion 211 is located on one side in the second direction D2. The second direction D2 is perpendicular to both the first direction D1 and the third direction D3. The bottom wall portion 211 extends along the first direction D1 and the third direction D3. When viewed from the second direction D2, the bottom wall portion 211 has a rectangular outer shape.

[0028] The peripheral side wall portion 212 is made of a resin composition and is molded integrally with the bottom wall portion 211. The peripheral side wall portion 212 stands from the outer circumferential end of the bottom wall portion 211 in the second direction D2 and forms an opening OP facing the side opposite to the bottom wall portion 211.

[0029] The peripheral side wall portion 212 has a pair of first wall portions 213 and a pair of second wall portions 214. The pair of first wall portions 213 are aligned in the first direction D1. The pair of first wall portions 213 extend along the third direction D3. The pair of second wall portions 214 are aligned in the third direction D3. The pair of second wall portions 214 extend along the first direction D1.

[0030] Hole 215 is provided to expose a portion of connecting conductive member 310 to the outside of case body 210. Hole 215 is closed by connecting conductive member 310. Specifically, hole 215 is provided in peripheral side wall 212, and more specifically, in second wall 214.

[0031] In this embodiment, the case body 210 has a plurality of holes 215 as the above-described hole 215. From one of the plurality of holes 215, which is different from the hole 215 described above, the external conductive member 320 is exposed.

[0032] The opening OP is closed by the lid 216. In this embodiment, at least the portion of the lid 216 that faces the peripheral side wall portion 212 is made of a resin composition. The lid 216 has a flat plate-like or film-like outer shape.

[0033] The lid 216 may be a laminate including a resin layer made of the resin composition and a barrier layer. Specifically, the lid 216 may be a laminate film in which a barrier layer made of aluminum or the like is laminated to a resin layer. The lid 216 may be a plate-like member in which a metal plate such as aluminum is laminated to a resin layer. The barrier layer or the metal plate may be disposed inside the resin layer.

[0034] The welded portion 217 is formed by thermally welding the lid 216 and the peripheral side wall portion 212 to each other. Instead of forming the welded portion 217, the lid 216 and the peripheral side wall portion 212 may be joined to each other by another known joining method such as an adhesive.

[0035] The partition portion 220 has electrical insulation at least on the surface facing the electrode body 100. The partition portion 220 is located between adjacent electrode bodies 100 to partition the storage space S of the case body 210.

[0036] The partition wall 220 has a base 221, a first protruding portion 222, and a second protruding portion 223 (see FIG. 4). The base 221 is a flat plate. The base 221 extends along a plane direction perpendicular to the first direction D1. That is, the base 221 extends along both the second direction D2 and the third direction D3.

[0037] The first protruding portion 222 protrudes from the base portion 221 to one side in the first direction D1. The first protruding portion 222 is in contact with a first electrode body 100A, which is one of the multiple electrode bodies 100.

[0038] The second protruding portion 223 protrudes from the base portion 221 to the other side in the first direction D1. The second protruding portion 223 is in contact with the second electrode body 100B, which is another one of the multiple electrode bodies 100.

[0039] The first protrusion 222 is curved in a convex shape toward the electrode body 100 (i.e., the first electrode body 100A) in contact with the first protrusion 222. The second protrusion 223 is curved in a convex shape toward the second electrode body 100B, which is the electrode body 100 (i.e., the second electrode body 100B) in contact with the second protrusion 223.

[0040] In this embodiment, the dimension of the first protrusion 222 in the first direction D1 is substantially constant from one side to the other side in the second direction D2 (see FIG. 6). However, the dimension of the first protrusion 222 in the first direction D1 does not have to be substantially constant as described above.

[0041] Fig. 7 is a partial cross-sectional view of the energy storage module according to each modified example of embodiment 1. In Fig. 7(A) to (C), the energy storage module according to each modified example is illustrated in a cross-sectional view similar to the partial cross-sectional view of the energy storage module 1 in Fig. 6.

[0042] As shown in Fig. 7(A), in a first modified example, the dimension of the first protrusion 222a in the first direction D1 increases toward the bottom wall 211. As shown in Fig. 7(B), in a second modified example, the dimension of the first protrusion 222b in the first direction D1 decreases toward the bottom wall 211. As shown in Fig. 7(C), in a third modified example, the dimension of the first protrusion 222c in the first direction D1 increases toward approximately the center in the second direction D2 of the accommodation space S. The dimension of the second protrusion 223 in the first direction D1 may also have a similar configuration to that of the first protrusions 222, 222a, 222b, and 222c.

[0043] The case 200 according to this embodiment has a plurality of partition walls 220. The plurality of partition walls 220 includes a first partition wall 220A and a second partition wall 220B. The plurality of partition walls 220 may include three or more partition walls.

[0044] In the storage space S of the case body 210, a first section S1 and a second section S2 adjacent to the first section S1 via the partition section 220 (first partition section 220A) are formed by the partition section 220 (first partition section 220A). In addition, in the storage space S, a third section S3 adjacent to the first section S1 via the first section S1 and the second partition section 220B is formed by the second partition section 220B. The third section S3 is located opposite the second section S2 as viewed from the first section S1.

[0045] Similar to the first partition wall portion 220A, the second partition wall portion 220B also has a base portion 221, a first protruding portion 222, and a second protruding portion 223. However, the second protruding portion 223 of the second partition wall portion 220B is in contact with the third electrode body 100C.

[0046] That is, of the multiple electrode bodies 100, the first electrode body 100A is housed in the first compartment S1. The second electrode body 100B is housed in the second compartment S2. The third electrode body 100C is housed in the third compartment. An electrolyte is injected into the housing space S (first compartment S1, second compartment S2, third compartment S3). Note that the electrolyte is not shown. The method of injecting the electrolyte is not particularly limited. The electrolyte may be injected from the opening OP before the opening OP is closed by the lid 216.

[0047] The partition walls 220 are made of a resin composition and are integrally formed with the bottom wall 211 and the peripheral side wall 212. In this embodiment, the partition walls 220 and the lid 216 may or may not be joined to each other by thermal welding.

[0048] In this embodiment, the above-mentioned method of "integrally molding" may include a method in which each component is molded and joined simultaneously in one step by a known method such as injection molding, or a method in which multiple components are molded separately and then joined to each other by a known joining method such as fusing, welding, or adhesive.

[0049] Here, a resin composition that can form the bottom wall portion 211, the peripheral side wall portion 212, the lid 216, and the plurality of partition portions 220 in this embodiment will be described.

[0050] The resin composition may contain, as a base polymer, polycarbonate, polyethylene, polypropylene, polyvinyl, polyamide, polyester, polyphenylene sulfide (PPS), polyphenylene ether, polystyrene, polycyclic olefin copolymer, acrylonitrile-butadiene-styrene copolymer, liquid crystal polymer (LCP), fluorine-based resin, mixtures thereof, alloys thereof, or copolymers thereof. The base polymer is not limited to these.

[0051] The resin composition may contain polyolefin, liquid crystal polymer, or fluororesin as a base polymer. The polyolefin may contain high density polyethylene (HDPE). High density polyethylene, liquid crystal polymer, or fluororesin has a relatively low water vapor transmission rate. Therefore, the case 200 containing a resin composition containing these has improved moisture transmission resistance.

[0052] The liquid crystal polymer may contain structural units derived from an oligomer of hydroxybenzoic acid. The liquid crystal polymer may further contain 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) in addition to the oligomer of hydroxybenzoic acid, and may be copolymerized with the oligomer of hydroxybenzoic acid (HBA).

[0053] Examples of the fluororesin include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), or mixtures or copolymers thereof. The fluororesin is hydrophobic. Therefore, based on the total weight of the resin composition, the resin composition may contain, for example, about 20% by weight or less, about 15% by weight or less, about 10% by weight or less, about 3% by weight to about 10% by weight, or about 5% by weight to about 10% by weight of the fluororesin. When the content of the fluororesin is within the above range, it is considered that the molded article made of the resin composition has an effect of blocking moisture from the surface of the molded article that comes into contact with the outside air.

[0054] In this embodiment, it is preferable that the base polymer of the resin composition constituting the lid 216 and the base polymer of the resin composition constituting the peripheral side wall portion 212 and the plurality of partition portions 220 are the same. This allows these components to be easily welded to each other. In turn, it is possible to easily form the welded portion 217. From the viewpoint of performing thermal welding, it is also preferable that the base polymer is polyethylene or polypropylene.

[0055] The resin composition may further contain an inorganic moisture absorbent or graphite from the viewpoint of suppressing water vapor transmission rate. In addition, the resin composition may further contain a substance other than graphite that is known as an existing moisture barrier substance.

[0056] Next, the connecting conductive members 310 and the external conductive members 320 will be described. In this embodiment, the energy storage module 1 includes a plurality of connecting conductive members 310. The plurality of connecting conductive members 310 include a first connecting conductive member 310A and a second connecting conductive member 310B. The plurality of connecting conductive members 310 may include three or more connecting conductive members. Furthermore, in this embodiment, the energy storage module 1 includes, as the external conductive member 320, a first external conductive member 320A and a second external conductive member 320B.

[0057] The connecting conductive member 310 (first connecting conductive member 310A, second connecting conductive member 310B) has a first end portion 311A, a second end portion 311B, a first inner surface portion 312A, a second inner surface portion 312B, a first outer surface portion 313A, and a second outer surface portion 313B.

[0058] In the first connection conductive member 310A, the first end 311A ​​is an end on one side of the first connection conductive member 310A in the first direction D1 and is embedded in the peripheral side wall 212 (one of the second wall portions 214) of the case body 210. The second end 311B is an end on the other side of the first connection conductive member 310A in the first direction D1 and is embedded in the peripheral side wall 212 (one of the second wall portions 214) of the case body 210.

[0059] In the first connecting conductive member 310A, the first inner surface portion 312A is exposed to the first section S1 and is electrically connected to the electrode tab (negative electrode tab 122n) of the first electrode body 100A. The second inner surface portion 312B is exposed to the second section S2 and is electrically connected to the electrode tab (positive electrode tab 112p) of the second electrode body 100B.

[0060] In the second connection conductive member 310B, the first end 311A ​​is an end on one side of the second connection conductive member 310B in the first direction D1 and is embedded in the peripheral side wall portion 212 (the other second wall portion 214) of the case body 210. The second end 311B is an end on the other side of the second connection conductive member 310B in the first direction D1 and is embedded in the peripheral side wall portion 212 (the other second wall portion 214) of the case body 210.

[0061] In the second connection conductive member 310B, the first inner surface portion 312A is exposed to the first section S1 and is electrically connected to the electrode tab (positive electrode tab 112p) of the first electrode body 100A. The second inner surface portion 312B is exposed to the third section S3 and is electrically connected to the electrode tab (negative electrode tab 122n) of the third electrode body 100C.

[0062] In each connecting conductive member 310, the first outer surface portion 313A is located on the opposite side to the first inner surface portion 312A, and is exposed to the outside of the case body 210 through the hole portion 215. Each connecting conductive member 310 is provided with a pressure release valve 314 that can release pressure on the first inner surface portion 312A side to the first outer surface portion 313A side.

[0063] In each connecting conductive member 310, the second outer surface portion 313B is located on the opposite side to the second inner surface portion 312B and is exposed to the outside of the case body 210 from another hole portion 215. Each connecting conductive member 310 is provided with another pressure release valve 315 capable of releasing pressure on the second inner surface portion 312B side to the first outer surface portion 313A side.

[0064] The first external conductive member 320A is aligned with the third electrode body 100C in the third direction D3 and is electrically connected to the third electrode body 100C. The second external conductive member 320B is aligned with the second electrode body 100B in the third direction D3 and is electrically connected to the second electrode body 100B.

[0065] Each external conductive member 320 has a third inner surface portion 321 , an external connection surface portion 322 , and a buried end portion 323 .

[0066] In the first external conductive member 320A, the third inner surface portion 321 is exposed to the accommodation space S (third section S3) and is electrically connected to the electrode tab (positive electrode tab 112p) of the third electrode body 100C. In the second external conductive member 320B, the third inner surface portion 321 is exposed to the accommodation space S (second section S2) and is electrically connected to the electrode tab (negative electrode tab 122n) of the second electrode body 100B.

[0067] In each external conductive member 320, the external connection surface portion 322 is exposed to the outside of the case body 210 in the first direction D1. The buried end portion 323 is an end portion on the opposite side to the external connection surface portion 322 in the first direction D1, and is buried in the case body 210.

[0068] Each external conductive member 320 further has a third outer surface portion 324. The third outer surface portion 324 is located on the opposite side to the third inner surface portion 321. The third outer surface portion 324 is exposed to the outside of the case body 210 through one of the multiple holes 215. Each external conductive member 320 is provided with a further pressure release valve 325 capable of releasing pressure on the third inner surface portion 321 side to the third outer surface portion 324 side.

[0069] Each connecting conductive member 310 and each outer conductive member 320 is made of a metal such as, for example, stainless steel, aluminum, or copper.

[0070] In this embodiment, the power storage module 1 further includes a plurality of current collecting members 400. The plurality of current collecting members 400 are disposed between the positive electrode tab 112p of each electrode body 100 and the connection conductive member 310 or the external conductive member 320, and between the negative electrode tab 122n of each electrode body 100 and the connection conductive member 310 or the external conductive member 320. Each current collecting member 400 is joined to each positive electrode tab 112p or each negative electrode tab 122n by welding. Each current collecting member 400 is joined to the adjacent first inner surface portion 312A, second inner surface portion 312B, or third inner surface portion 321 by welding.

[0071] The multiple current collecting members 400 may include a metal material such as aluminum or copper. The power storage module 1 does not necessarily need to include the current collecting members 400. When the power storage module 1 does not include the current collecting members 400, each of the positive electrode tabs 112p and each of the negative electrode tabs 122n may be directly joined to the adjacent first inner surface portion 312A, second inner surface portion 312B, or third inner surface portion 321 by welding.

[0072] As described above, the energy storage module 1 according to the first embodiment of the present disclosure includes a plurality of electrode bodies 100 and a case 200. The plurality of electrode bodies 100 are arranged in a first direction D1. The case 200 accommodates the plurality of electrode bodies 100. The case 200 includes a case body 210 and at least one partition wall portion 220. The case body 210 has electrical insulation properties and surrounds the plurality of electrode bodies 100. The partition wall portion 220 has electrical insulation properties and is located between the plurality of adjacent electrode bodies 100 to partition the accommodation space S of the case body 210. The partition wall portion 220 includes a base portion 221 and a first protruding portion 222. The base portion 221 is plate-shaped and extends along a planar direction perpendicular to the first direction D1. The first protruding portion 222 protrudes from the base portion 221 to one side in the first direction D1 and contacts one of the multiple electrode bodies 100.

[0073] According to the above configuration, the storage space S of the case 200 can be enlarged by making the base 221 relatively thin. On the other hand, the thickness of the partition wall 220 is relatively thick in the portion formed by the first protruding portion 222 and the base 221. Therefore, by configuring the first protruding portion 222 and the electrode body 100 to be in contact with each other, a decrease in the holding force of the electrode body 100 in the storage space S of the case 200 can be suppressed.

[0074] Furthermore, in the energy storage module 1 according to the first embodiment of the present disclosure, the first protrusion 222 is curved in a convex shape toward the electrode body 100 in contact with the first protrusion 222.

[0075] According to the above configuration, since the first protruding portion 222 is curved in a convex shape, concentration of stress on the portion of the electrode body 100 that comes into contact with the first protruding portion 222 can be suppressed.

[0076] In the power storage module 1 according to the first embodiment of the present disclosure, the dimension of the first protrusion 222a in the first direction D1 may increase toward the bottom wall portion 211.

[0077] According to the above configuration, the electrode body 100 can be easily inserted from the opening OP side into the storage space S partitioned by the partition 220. Also, the inner surface of the first protrusion 222a is inclined with respect to the second direction D2, which can function as a so-called draft gradient. This can facilitate molding of the case body 210.

[0078] In the power storage module 1 according to the first embodiment of the present disclosure, the dimension of the first protrusion 222b in the first direction D1 may decrease toward the bottom wall portion 211.

[0079] According to the above configuration, the first protrusion 222b can prevent the electrode body 100 accommodated in the accommodation space S partitioned by the partition 220 from being displaced in the second direction D2.

[0080] (Embodiment 2) Hereinafter, a description will be given of an electric storage module according to a second embodiment of the present disclosure. In the electric storage module according to the second embodiment of the present disclosure, the structure of the lid is mainly different from that of the electric storage module according to the first embodiment of the present disclosure. Therefore, in the electric storage module according to the second embodiment of the present disclosure, the description of the same configuration and effects as those of the first embodiment will not be repeated.

[0081] Fig. 8 is an exploded perspective view in which the electricity storage module according to the second embodiment is partially disassembled. As shown in Fig. 8, in the second embodiment of the present disclosure, the lid 216a has a lid main body 218 and a gasket 219. The gasket 219 is sandwiched between the lid main body 218 and the peripheral side wall 212a. This makes it possible to improve the airtightness of the case main body 210 in a relatively simple manner.

[0082] The lid main body 218 may have the same configuration as the lid 216 in the first embodiment. From the viewpoint of increasing rigidity, the lid main body 218 is preferably a plate-like member containing a metal plate inside a resin composition. The gasket 219 may be a plate-like member or a linear member such as an O-ring. The gasket 219 may be further disposed between the lid main body 218 and each partition wall 220. The portion of the peripheral side wall 212a that contacts the gasket 219 may have a shape that follows the outer shape of the gasket 219 (for example, a groove-like outer shape).

[0083] The lid 216a may further include a plurality of fastening members 250. The fastening members 250 are, for example, bolts. The lid main body portion 218 and the peripheral side wall portion 212a are fixed to each other by the plurality of fastening members 250.

[0084] (Embodiment 3) Hereinafter, a description will be given of an electricity storage module according to a third embodiment of the present disclosure. In the electricity storage module according to the third embodiment of the present disclosure, the structure of the lid main body is mainly different from the electricity storage module according to the second embodiment of the present disclosure. Therefore, in the electricity storage module according to the third embodiment of the present disclosure, the description of the same configuration and effects as those of the second embodiment will not be repeated.

[0085] FIG. 9 is an exploded perspective view of the power storage module according to the third embodiment, which is partially exploded. As shown in FIG. 9, in this embodiment, the lid body 218b has a claw 260 provided along the circumferential edge. The peripheral wall 212b has a groove 270 provided along the outer surface of the peripheral wall 212b. The lid body 218b is fixed by fitting the claw 260 into the groove 270. In this embodiment, a weight made of another member may be provided on the center of the lid body 218b. This makes it possible to suppress deformation of the center of the lid body 218b with the fitting portion of the claw 260 and the groove 270 as a fulcrum.

[0086] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0087] 1 Energy storage module, 100 Electrode body, 100A First electrode body, 100B Second electrode body, 100C Third electrode body, 110 Positive electrode, 112 Positive electrode current collector foil, 112p Positive electrode tab, 114 Positive electrode active material layer, 120 Negative electrode, 122 Negative electrode current collector foil, 122n Negative electrode tab, 124 Negative electrode active material layer, 130 Separator, 132a Interposition portion, 132b Upper folded portion, 132c Lower folded portion, 132d Outermost coating portion, 132e End, 200 Case, 210 Case body, 211 Bottom wall portion, 212, 212a, 212b Peripheral side wall portion, 213 First wall portion, 214 Second wall portion, 215 Hole portion, 216, 216a Lid, 217 Welding portion, 218, 218b, cover body portion, 219, gasket, 220, partition portion, 220A, first partition portion, 220B, second partition portion, 221, base portion, 222, 222a, 222b, 222c, first protrusion portion, 223, second protrusion portion, 250, fastening member, 260, claw portion, 270, groove portion, 310, connecting conductive member, 310A, first connecting conductive member, 310B, second connecting conductive member, 311A, first end portion, 311B, second end portion, 312A, first inner surface portion, 312B, second inner surface portion, 313A, first outer surface portion, 313B, second outer surface portion, 314, 315, 325, pressure release valve, 320, outer conductive member, 320A, first outer conductive member, 320B, second outer conductive member, 321 A third inner surface portion, 322 an external connection surface portion, 323 a buried end portion, 324 a third outer surface portion, 400 a current collecting member, OP an opening, S an accommodation space, S1 a first section, S2 a second section, and S3 a third section.

Claims

1. A plurality of electrode bodies arranged in a first direction; A case that houses the plurality of electrode bodies, The case is A case body having electrical insulation properties and surrounding the plurality of electrode bodies; at least one partition wall portion having electrical insulation properties and positioned between adjacent ones of the plurality of electrode bodies to divide an accommodation space of the case body; the partition portion has a plate-shaped base extending along a planar direction perpendicular to the first direction, and a first protrusion protruding from the base to one side in the first direction and contacting one of the plurality of electrode bodies.

2. The energy storage module according to claim 1 , wherein the first protrusion is curved in a convex shape toward the electrode body in contact with the first protrusion.

3. The case body includes: A bottom wall portion formed of a resin composition and located on one side in a second direction perpendicular to the first direction; a peripheral wall portion that is made of a resin composition and is molded integrally with the bottom wall portion, the peripheral wall portion rising in the second direction from a peripheral end of the bottom wall portion and forming an opening facing the side opposite to the bottom wall portion; a lid for closing the opening, the partition wall is integrally formed with the bottom wall and the peripheral side wall, The energy storage module according to claim 1 , wherein a dimension of the first protrusion in the first direction increases toward the bottom wall portion.

4. The case body includes: A bottom wall portion formed of a resin composition and located on one side in a second direction perpendicular to the first direction; a peripheral wall portion that is made of a resin composition and is molded integrally with the bottom wall portion, the peripheral wall portion rising in the second direction from a peripheral end of the bottom wall portion and forming an opening facing the side opposite to the bottom wall portion; a lid for closing the opening, the partition wall is integrally formed with the bottom wall and the peripheral side wall, The energy storage module according to claim 1 , wherein a dimension of the first protrusion in the first direction decreases toward the bottom wall portion.

Images