Energy storage module

Abstract

This power storage module has a power storage device and a holder. The power storage device comprises multiple cylindrical electrode bodies, and a film outer casing comprising multiple housing parts, which envelop the electrode bodies individually, and a sealing part, which seals the housing parts and links the housing parts to each other. The holder has a side plate which extends in the arrangement direction. The side plate has multiple recesses which are aligned in the arrangement direction and in which the housing parts fit, a first and second edge which are aligned in the axial direction and extend in the arrangement direction, and a third and fourth edge which are aligned in the arrangement direction and extend in the axial direction. Further, the holder is configured as part of a member constituting the side plate, and has a first wall plate which protrudes orthogonally from at least some areas of the first edge.

Description

[Technical Field]

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

[0002] Conventionally, a power storage module equipped with a plurality of cylindrical power storage devices (e.g., batteries) has been known (see, for example, Patent Document 1). In the power storage module disclosed in Patent Document 1, each power storage device has a cylindrical outer can, and each outer can houses a wound electrode body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-170613 Summary of the Invention [Problem to be solved by the invention]

[0004] Energy storage modules are sometimes used as power sources for vehicles and mobile devices. Therefore, it is desirable to reduce the weight of energy storage modules. One possible method for reducing the weight of an energy storage module is to encase multiple electrode assemblies in a common film exterior while maintaining individual sealing. This allows for an energy storage device having multiple electrode assemblies. In this case, the exterior cans that house each electrode assembly can be eliminated, thereby reducing the weight of the energy storage module. On the other hand, energy storage devices with a structure in which multiple electrode assemblies are sealed in a film exterior assembly are prone to significant deformation due to impacts, etc., due to the high flexibility of the film exterior assembly. Therefore, it is desirable to increase the holding strength of the energy storage device.

[0005] The present disclosure has been made in consideration of these circumstances, and one of its purposes is to provide a technology for increasing the holding strength of an energy storage device having a structure in which multiple electrode bodies are sealed in a film exterior body. [Means for solving the problem]

[0006] One aspect of the present disclosure is an energy storage module. The energy storage module includes an energy storage device and a holder that holds the energy storage device. The energy storage device includes a plurality of cylindrical electrode assemblies, a plurality of housings that individually encase the electrode assemblies, and a film exterior body having sealing portions that seal each housing portion and connect the housing portions to one another. The holder includes a side plate extending in the arrangement direction of the plurality of electrode assemblies, the side plate having a plurality of recesses that are aligned in the arrangement direction and into which the housing portions fit, first and second edges that are aligned in the axial direction of the electrode assemblies and extend in the arrangement direction, and third and fourth edges that are aligned in the arrangement direction and extend in the axial direction; and a first wall plate that is formed as part of a member that constitutes the side plate and protrudes from at least a portion of the first edge in a direction perpendicular to the axial direction and the arrangement direction.

[0007] Any combination of the above components, and conversion of the expression of the present disclosure into a method, device, system, etc., are also valid aspects of the present disclosure. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to increase the holding strength of an electricity storage device having a structure in which a plurality of electrode bodies are sealed in a film exterior body. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view of an electricity storage device included in an electricity storage module according to an embodiment. [Figure 2] Fig. 2(A) is a schematic diagram of the electricity storage device as viewed from the axial direction, and Fig. 2(B) is a schematic diagram of the electricity storage device as viewed from the perpendicular direction. [Figure 3] 3(A) to 3(C) are process diagrams of a method for manufacturing an electricity storage device. [Figure 4] 4(A) to 4(C) are process diagrams of a method for manufacturing an electricity storage device. [Figure 5] FIG. 1 is a perspective view of an electricity storage module according to an embodiment. [Figure 6] FIG. 2 is an exploded perspective view of the electricity storage module. [Figure 7]7(A) and 7(B) are perspective views of the device units that make up the electricity storage module. [Figure 8] 8(A) and 8(B) are perspective views of the holder. [Figure 9] FIG. 2 is a cross-sectional view of the storage module. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present disclosure will be described below with reference to preferred embodiments and drawings. The embodiments are illustrative and do not limit the present disclosure, and all features and combinations thereof described in the embodiments are not necessarily essential to the present disclosure. The same or equivalent components, parts, and processes shown in each drawing are designated by the same reference numerals, and redundant descriptions will be omitted where appropriate. The scale and shape of each part shown in each drawing are set for convenience to facilitate explanation and should not be interpreted as limiting unless otherwise specified. Furthermore, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, these terms do not indicate any order or importance, but are intended to distinguish one configuration from another. Furthermore, some components that are not important for explaining the embodiments are omitted from each drawing.

[0011] FIG. 1 is a perspective view of an energy storage device 1 included in an energy storage module 100 according to an embodiment. FIG. 2(A) is a schematic diagram of the energy storage device 1 as viewed from an axial direction A. FIG. 2(B) is a schematic diagram of the energy storage device 1 as viewed from an orthogonal direction C. For ease of explanation, FIG. 2(B) also illustrates the inside of a film exterior body 4. The state before the film exterior body 4 is folded is illustrated by a dashed line. In this embodiment, the direction in which the spiral axis (the central axis of the cylinder) of the electrode body 2 extends is referred to as the axial direction A, the direction in which the multiple electrode bodies 2 are arranged is referred to as the arrangement direction B, and the direction orthogonal to the axial direction A and the arrangement direction B is referred to as the orthogonal direction C.

[0012] The power storage device 1 of this embodiment is, for example, a rechargeable secondary battery such as a lithium ion battery, a nickel-metal hydride battery, or a nickel-cadmium battery, or a capacitor such as an electric double layer capacitor. The power storage device 1 has a plurality of electrode bodies 2 and a film exterior body 4. The power storage device 1 of this embodiment has eight electrode bodies 2, but the number is not particularly limited as long as it is two or more.

[0013] Each electrode body 2 is cylindrical, and has a spirally wound structure in which a strip-shaped first electrode plate and a strip-shaped second electrode plate are stacked with an inter-electrode separator sandwiched between them. As an example, the first electrode plate is a negative electrode plate, and the second electrode plate is a positive electrode plate. A first electrode lead 8 is electrically connected to the first electrode plate. A second electrode lead 10 is electrically connected to the second electrode plate. For example, the first electrode lead 8 and the second electrode lead 10 are strip-shaped (rectangular and elongated in one direction), and one end of each is welded to the corresponding electrode plate. The multiple electrode bodies 2 are oriented so that the axial directions A of the electrode bodies 2 are parallel to each other, and are arranged at predetermined intervals in an arrangement direction B. The multiple electrode bodies 2 are wrapped in a common film exterior body 4.

[0014] The film exterior body 4 has a structure in which, for example, two laminate films are stacked. Each laminate film has a structure in which a thermoplastic resin sheet is laminated on both sides of a metal sheet, such as aluminum. The film exterior body 4 also has multiple storage sections 12 and a sealing section 14. The multiple storage sections 12 are arranged at predetermined intervals in the arrangement direction B. Each storage section 12 is cylindrical and individually encloses and stores each electrode body 2. Each storage section 12 is formed by a bag section provided in the film exterior body 4. The bag sections are portions of the two laminate films that are spaced apart from each other. Therefore, each storage section 12 protrudes from the sealing section 14 in accordance with the shape of the side surface of the electrode body 2. Each storage section 12 stores an electrolyte 16 together with the electrode body 2.

[0015] The sealing portion 14 surrounds the outer periphery of each storage portion 12 to seal it. The sealing portion 14 is formed, for example, by a welded portion of a thermoplastic resin sheet. The welded portion is obtained by subjecting the outer periphery of the bag portion of the film exterior body 4 to a thermocompression treatment, thereby welding the thermoplastic resin sheets of the two laminate films together. The sealing portion 14 seals each storage portion 12 and also connects the multiple storage portions 12 to one another.

[0016] The ends of the first electrode lead 8 and the second electrode lead 10 opposite to the end connected to the electrode body 2 protrude outside the film exterior body 4. The interface between each electrode lead and the film exterior body 4 is sealed with a known sealant. In this embodiment, the first electrode lead 8 and the second electrode lead 10 connected to each electrode body 2 protrude on opposite sides to each other in the axial direction A. Furthermore, each first electrode lead 8 protrudes on the same side.

[0017] The film exterior body 4 bends or curves between adjacent storage sections 12 and snakes in the arrangement direction B. That is, the film exterior body 4, and more specifically the sealing section 14, extends in a roughly zigzag pattern when viewed from the axial direction A. By folding the film exterior body 4 in a zigzag pattern, the spacing between the storage sections 12 in the arrangement direction B can be made narrower than in the state before folding, and therefore the length of the energy storage device 1 in the arrangement direction B can be shortened.

[0018] Furthermore, in this embodiment, the multiple storage sections 12 are arranged so that their centers are aligned on the same straight line when viewed from the axial direction A while the film exterior body 4 is in a serpentine state. This makes it possible to prevent the size of the energy storage device 1 in the orthogonal direction C from increasing, compared to when the multiple storage sections 12 are arranged so that their centers are offset in the orthogonal direction C. Furthermore, the zigzag-folded sealing section 14 is located inside the storage sections 12 in the orthogonal direction C. This makes it possible to prevent the size of the energy storage device 1 in the orthogonal direction C from increasing when the film exterior body 4 is folded. Note that, in the present disclosure, the centers of the multiple storage sections 12 do not necessarily have to be aligned on the same straight line.

[0019] The sealing portion 14 has a pair of first portions 14a and a pair of second portions 14b that surround the periphery of each storage portion 12. The pair of first portions 14a are aligned in the axial direction A, sandwiching each storage portion 12 therebetween, and seal the ends of each storage portion 12 in the axial direction A. In this embodiment, the first portions 14a extend linearly through the center of the storage portion 12 when viewed from the axial direction A. The pair of second portions 14b are aligned in a direction perpendicular to the axial direction A, sandwiching each storage portion 12 therebetween, and extend in the axial direction A to connect the pair of first portions 14a.

[0020] The two second portions 14b located between two adjacent storage sections 12 are connected to each other at a predetermined angle lang=EN-US>θ, i.e., non-linearly. The bending directions of the connecting portions of the two second portions 14b alternate among the multiple connecting portions aligned in the arrangement direction B. As a result, the film exterior body 4 extends in a zigzag pattern in the arrangement direction B. Each of the two second portions 14b may also be bent in a wavy manner.

[0021] An example of a method for manufacturing the energy storage device 1 is shown below. FIGS. 3(A) to 3(C) and 4(A) to 4(C) are process diagrams of the method for manufacturing the energy storage device 1. First, as shown in FIG. 3(A), a first laminate film 20a is prepared. A plurality of semi-cylindrical depressions 18 are formed in advance in the first laminate film 20a. The depressions 18 are formed, for example, by subjecting the first laminate film 20a to a known process such as press working. An electrode body 2 is placed in each depression 18. A first electrode lead 8 and a second electrode lead 10 are connected to the electrode body 2 in advance. A sealant (not shown) is provided in the first electrode lead 8 and the second electrode lead 10.

[0022] 3(B), the second laminate film 20b is then superimposed on the first laminate film 20a to form the film exterior housing 4. The second laminate film 20b has semi-cylindrical depressions 18 formed in positions facing the depressions 18 in the first laminate film 20a. Therefore, by superimposing the first laminate film 20a and the second laminate film 20b, a bag portion, in other words, a storage portion 12, is formed by the pair of depressions 18. The method for forming the depressions 18 in the second laminate film 20b is the same as the method for forming the depressions 18 in the first laminate film 20a. With the electrode body 2 housed in the storage portion 12, the tip of the first electrode lead 8 and the tip of the second electrode lead 10 protrude outside the film exterior housing 4.

[0023] Next, as shown in FIG. 3(C), a thermocompression process is performed on a portion of the film exterior body 4 to form a welded portion 22. The portion of the film exterior body 4 that is not subjected to the thermocompression process becomes a non-welded portion 24. The non-welded portion 24 is arranged so as to connect each housing section 12 to the outside of the film exterior body 4. In the present embodiment, the non-welded portion 24 is provided so as to connect one of the four sides of each housing section 12 from which the first electrode lead 8 protrudes to the outside of the film exterior body 4. The remaining three sides of each housing section 12 are surrounded by the welded portion 22. The interface between the film exterior body 4 and the second electrode lead 10 is sealed with a sealant.

[0024] Next, as shown in FIG. 4(A), electrolyte 16 is poured into each housing section 12 through the non-welded sections 24. After the electrolyte 16 is poured, thermocompression bonding is also performed on the non-welded sections 24, as shown in FIG. 4(B). As a result, a sealing section 14 is formed that surrounds the entire periphery of each housing section 12. The interface between the film exterior body 4 and the first electrode lead 8 is sealed with a sealant. Next, as shown in FIG. 4(C), the film exterior body 4 is folded in a zigzag shape. Through the above steps, the electricity storage device 1 is obtained.

[0025] The manufacturing method of the energy storage device 1 is not limited to the above. For example, each electrode body 2 may be wrapped in a single laminate film having twice the length of the energy storage device 1, which is folded in half. Furthermore, when the required amount of electrolyte solution 16 is small, the step of injecting the electrolyte solution 16 shown in FIG. 4(A) can be omitted by pre-impregnating the inter-electrode separator with the electrolyte solution 16. In this case, in the thermocompression bonding step shown in FIG. 3(C), the entire periphery of each housing portion 12 is subjected to thermocompression bonding to form the sealing portion 14.

[0026] The energy storage device 1 is incorporated into an energy storage module 100 according to the present embodiment, which will be described below. Fig. 5 is a perspective view of the energy storage module 100 according to the embodiment. Fig. 6 is an exploded perspective view of the energy storage module 100. Figs. 7(A) and 7(B) are perspective views of an apparatus unit 130 constituting the energy storage module 100. Figs. 8(A) and 8(B) are perspective views of a holder 104. Fig. 9 is a cross-sectional view of the energy storage module 100. Note that in Figs. 5, 6, and 9, the illustration of the energy storage device 1 is simplified, and only the housing section 12 is shown. Furthermore, in Fig. 9, the interior of the housing section 12 is not shown.

[0027] The energy storage module 100 includes an energy storage device 1 and a holder 104. The energy storage module 100 of this embodiment includes a plurality of energy storage devices 1 and a plurality of holders 104. As an example, one energy storage device 1 and one holder 104 are combined to form one equipment unit 130, and the energy storage module 100 is made up of six equipment units 130. The number of equipment units 130 that make up the energy storage module 100 is not particularly limited, and may be one, or three or more. Furthermore, in the equipment unit 130, a plurality of energy storage devices 1 may be assembled to one holder 104.

[0028] The equipment units 130 are arranged in the orthogonal direction C. The orientation of the equipment units 130 is determined so that the housing sections 12 of the energy storage devices 1 are aligned in the same direction. Two energy storage devices 1 adjacent to each other in the orthogonal direction C are arranged offset from each other in the arrangement direction B so that the axis of the electrode body 2 of one energy storage device 1 is positioned between the axes of two adjacent electrode bodies 2 of the other energy storage device 1. In other words, the housing section 12 of one energy storage device 1 fits into the gap between the two housing sections 12 of the other energy storage device 1. This makes it possible to reduce the dimension of the energy storage module 100 in the orthogonal direction C.

[0029] In each device unit 130, the power storage device 1 is held by a holder 104. The holder 104 of this embodiment has a side plate 112, a first wall plate 144, a second wall plate 146, a third wall plate 148, and a fourth wall plate 150.

[0030] The side plate 112 is a plate extending in the arrangement direction B. The side plate 112 has a plurality of recesses 112a aligned in the arrangement direction B. Each recess 112a is groove-shaped and extends in the axial direction A. When the holder 104 is assembled to the energy storage device 1, each of the accommodation sections 12 of the energy storage device 1 facing the side plate 112 fits into each recess 112a. As a result, the curved surfaces of the plurality of recesses 112a extend along the curved surfaces of each accommodation section 12. This makes it possible to hold the energy storage device 1 more stably. In particular, it is possible to restrict displacement of the energy storage device 1 in the arrangement direction B. Note that it is sufficient that the recesses 112a accommodate at least a portion of the curved surface of the accommodation section 12 facing the recess 112a.

[0031] Furthermore, at least a portion of the side plate 112 in this embodiment is corrugated with repeated concave and convex portions in the arrangement direction B, and the plurality of recesses 112a are provided in this corrugated portion. That is, when viewed from one main surface side, the plurality of recesses 112a and the plurality of protrusions 112b are alternately arranged in the arrangement direction B. In this embodiment, when viewed from the main surface side of each device unit 130 facing the energy storage device 1, the portions curved in a direction away from the energy storage device 1 are called recesses 112a, and the portions curved in a direction approaching the energy storage device 1 are called protrusions 112b.

[0032] Therefore, the accommodation sections 12 of the energy storage devices 1 arranged on both sides of the side plate 112 can be fitted into the side plate 112. Specifically, when the side plate 112 is viewed from one main surface, the accommodation sections 12 of one energy storage device 1 are fitted into the recesses 112a and the protrusions 112b, respectively. Furthermore, the accommodation sections 12 of the other energy storage device 1 are fitted into the protrusions 112b (which appear as recesses when viewed from the opposite side) from the back surface side. This can further improve the stability of each energy storage device 1 in the energy storage module 100. The side plate 112 may be made of a plate material that is thicker than a corrugated plate and has a plurality of recesses arranged in the arrangement direction B on both sides.

[0033] The side plate 112 has a rectangular shape when viewed from the orthogonal direction C and includes a first edge 112c, a second edge 112d, a third edge 112e, and a fourth edge 112f. The first edge 112c and the second edge 112d are aligned in the axial direction A and extend in the arrangement direction B. For convenience, in this embodiment, the first edge 112c is positioned on the upper side and the second edge 112d is positioned on the lower side; however, the first edge 112c may be positioned on the lower side and the second edge 112d may be positioned on the upper side. The third edge 112e and the fourth edge 112f are aligned in the arrangement direction B and extend in the axial direction A.

[0034] The first wall panel 144 protrudes in the orthogonal direction C from at least a portion of the first edge 112c. The second wall panel 146 protrudes in the orthogonal direction C from at least a portion of the second edge 112d. The third wall panel 148 protrudes in the orthogonal direction C from at least a portion of the third edge 112e. The fourth wall panel 150 protrudes in the orthogonal direction C from at least a portion of the fourth edge 112f. In this disclosure, "protruding in the orthogonal direction C" means that the end of the wall panel on the side panel 112 side and the opposite end are misaligned in the orthogonal direction C.

[0035] As shown in the figure, the first edge 112c includes a flat plate-shaped portion extending in the arrangement direction B. The first wall panel 144 bends and protrudes from one end of this flat plate-shaped portion in the axial direction A. The second edge 112d includes a flat plate-shaped portion extending in the arrangement direction B. The second wall panel 146 bends and protrudes from one end of this flat plate-shaped portion in the axial direction A. The third edge 112e includes a flat plate-shaped portion extending in the axial direction A. The third wall panel 148 bends and protrudes from one end of this flat plate-shaped portion in the arrangement direction B. The fourth edge 112f includes a flat plate-shaped portion extending in the axial direction A. The fourth wall panel 150 bends and protrudes from one end of this flat plate-shaped portion in the arrangement direction B. 9, when the first wall panel 144 and the second wall panel 146 protrude from each edge toward one side in the orthogonal direction C, the flat portion is preferably disposed adjacent to the other end side (the side opposite the protruding direction of each wall panel) within the extension range of the holder 104 in the orthogonal direction C. With this configuration, the dimensions of the first wall panel 144 and the second wall panel 146 in the orthogonal direction C can be increased, and the rigidity of the side panel 112 can be further increased.

[0036] In this embodiment, the first wall panel 144 to the fourth wall panel 150 protrude to the same side in the orthogonal direction C. However, this configuration is not limited thereto, and any two wall panels may protrude in opposite directions as long as it is technically compatible. Also, as an example, the first wall panel 144 and the second wall panel 146 have a shape that is longer in the arrangement direction B than in the orthogonal direction C. As an example, the third wall panel 148 and the fourth wall panel 150 have a shape that is longer in the axial direction A than in the orthogonal direction C.

[0037] Furthermore, the third wall panel 148 is connected to the first wall panel 144 and the second wall panel 146. Similarly, the fourth wall panel 150 is connected to the first wall panel 144 and the second wall panel 146. In this embodiment, the first wall panel 144 protrudes from the entire first edge 112c. The second wall panel 146 protrudes from the entire second edge 112d. The third wall panel 148 protrudes from the entire third edge 112e. The fourth wall panel 150 protrudes from the entire fourth edge 112f. Therefore, the entire periphery of the side panel 112 is surrounded by the first wall panel 144, the second wall panel 146, the third wall panel 148, and the fourth wall panel 150. That is, the holder 104 is tray-shaped with the side panel 112 as the bottom panel and the first to fourth wall panels 144 to 150 as annular edge walls rising from the periphery of the bottom panel. The first wall panel 144 and the second wall panel 146 may be connected to only one of the third wall panel 148 and the fourth wall panel 150. Also, all of the first to fourth wall panels 144 to 150 do not have to be connected to the other wall panels. That is, each wall panel may protrude independently.

[0038] The first wall panel 144, the second wall panel 146, the third wall panel 148, and the fourth wall panel 150 are formed as part of the components that make up the side panel 112. In this disclosure, "formed as part of the components that make up the side panel 112" means that the side panel 112 and each wall panel, which are originally separate bodies, are not joined together as a result of being fixed to each other by a known fixing method such as welding or adhesive, but rather that the side panel 112 and each wall panel are fabricated into a single member by a known molding process such as press working or injection molding. In other words, each wall panel is formed by a portion of the component that makes up the side panel 112 extending from each edge in the orthogonal direction C.

[0039] Holder 104 is formed, for example, by pressing a single metal plate. Note that holder 104 may be made of resin as long as a predetermined level of rigidity can be obtained. In this case, holder 104 is formed, for example, by injection molding of the resin. Examples of metals used for holder 104 include aluminum, aluminum alloys, and steel. Examples of resins used for holder 104 include thermoplastic resins such as polypropylene (PP), polybutylene terephthalate (PBT), polycarbonate (PC), and Noryl (registered trademark) resin (modified PPE); and fiber-reinforced plastics (FRP) including carbon fiber-reinforced plastics (CFRP) and glass fiber-reinforced plastics (GFRP).

[0040] The holder 104 is oriented so that the main surface of the side plate 112 faces the orthogonal direction C. When the energy storage device 1 is assembled to the holder 104, one of the main surfaces in the orthogonal direction C is covered by the side plate 112. As an example, the side plate 112 is fixed to the opposing energy storage device 1 by an adhesive placed in the recess 112a. The adhesive is preferably an insulating adhesive. An insulating sheet may be interposed between the energy storage device 1 and the holder 104.

[0041] Furthermore, when viewed from the axial direction A, a portion of the energy storage device 1 is covered by the first wall plate 144 and the second wall plate 146. The protruding heights of the first wall plate 144 and the second wall plate 146 in the orthogonal direction C are adjusted so as not to interfere with the first electrode lead 8 and the second electrode lead 10. Furthermore, when viewed from the arrangement direction B, a portion of the energy storage device 1 is covered by the third wall plate 148 and the fourth wall plate 150. In this embodiment, the protruding heights of the third wall plate 148 and the fourth wall plate 150 are aligned with the protruding heights of the first wall plate 144 and the second wall plate 146. Note that the protruding heights of the respective wall plates may be uneven.

[0042] The energy storage devices 1 are arranged in the orthogonal direction C with the holders 104 assembled thereto. That is, a plurality of equipment units 130 are arranged in the orthogonal direction C. At this time, the energy storage devices 1 are arranged so that the exposed surfaces not covered by the holders 104 face the same direction. With the equipment units 130 arranged, the exposed surface of each energy storage device 1 is covered by the side plate 112 of the adjacent equipment unit 130 and fixed with an adhesive. As a result, at least some of the energy storage devices 1 are sandwiched between the two side plates 112. Furthermore, at least some of the side plates 112 are sandwiched between the two energy storage devices 1. Note that adhesive may be provided on only one of the side plates 112 arranged on both sides of the energy storage device 1.

[0043] With the multiple equipment units 130 arranged in the orthogonal direction C, a connecting member 152 is placed on the third wall plate 148 and the fourth wall plate 150 of each holder 104. The connecting member 152 is a strip-shaped member that extends across the multiple equipment units 130 in the orthogonal direction C. The connecting member 152 is made of, for example, the same material as the holder 104. Then, a known joining process such as laser welding is performed on the overlapping portion of the third wall plate 148 and the connecting member 152 and the overlapping portion of the fourth wall plate 150 and the connecting member 152. As a result, the holders 104 are connected to each other, and the multiple equipment units 130 are integrated.

[0044] In the present embodiment, two strip-shaped connecting members 152 are arranged on each side of the energy storage module 100 in the arrangement direction B, but the shape and arrangement of the connecting members 152 are not limited to this. Furthermore, the method of connecting the equipment units 130 is not limited to using the connecting members 152. For example, the third wall plate 148 and the fourth wall plate 150 may be protruded to a position where they overlap with the third wall plate 148 and the fourth wall plate 150 of the adjacent equipment unit 130, and a joining process may be performed at the overlapping portions of the two third wall plates 148 and the overlapping portions of the two fourth wall plates 150.

[0045] The equipment unit 130 located at one end in the orthogonal direction C has no other equipment units 130 on the exposed surface side. Therefore, an end holder 105 is attached to the exposed surface of the power storage device 1 in the equipment unit 130. The end holder 105 has the same shape as the holder 104, except that the protruding direction of each wall panel is opposite to that of the holder 104. In the holder 104 of this embodiment, the protruding height of each wall panel is adjusted to a height that does not interfere with adjacent holders 104, and the front and back of the side panels 112 have the same shape, so that the holder 104 can be reused as the end holder 105 simply by changing the orientation of the holder 104. Note that instead of the end holder 105, a holder 104 having the same shape and orientation as the holder 104 of each equipment unit 130 may be used.

[0046] Furthermore, the side plate 112 of the present embodiment is provided with a plurality of through holes 132. The plurality of through holes 132 penetrates the side plate 112 in the plate thickness direction of the side plate 112. The plurality of through holes 132 are also arranged in a matrix. By providing the through holes 132, it is possible to reduce the weight of the energy storage module 100.

[0047] An insulating plate (not shown) may be placed on the first wall plate 144 or the second wall plate 146. This insulating plate functions as a support member for, for example, a bus bar (not shown). The insulating plate is made of, for example, an insulating resin. Examples of resins that can be used to make the insulating plate include thermoplastic resins such as polypropylene (PP), polybutylene terephthalate (PBT), polycarbonate (PC), and Noryl (registered trademark) resin (modified PPE); and fiber-reinforced plastics (FRP) including carbon fiber-reinforced plastics (CFRP) and glass fiber-reinforced plastics (GFRP).

[0048] With the multiple device units 130 arranged in the orthogonal direction C and connected to each other, insulating plates are placed on at least some of the first wall plates 144 and second wall plates 146, and a bus bar is mounted on them. The first electrode lead 8 and the second electrode lead 10 of each energy storage device 1 are then electrically connected to the bus bar. This electrically connects the multiple electrode bodies 2. For example, each electrode lead is joined to the bus bar by a known joining process such as laser welding. By interposing the insulating plate between the energy storage device 1 and the bus bar, electrical connection between each energy storage device 1 and the bus bar can be suppressed in areas other than the electrode leads.

[0049] In this embodiment, a plurality of first electrode leads 8 protrude to the same side in each energy storage device 1. Furthermore, the orientation of two adjacent energy storage devices 1 is determined so that the first electrode leads 8 protrude to the same side. Therefore, when each electrode lead is joined to the bus bar, all of the electrode bodies 2 are connected in parallel to each other. The manner of electrical connection of each electrode body 2 is not particularly limited. For example, in each energy storage device 1, the first electrode leads 8 and the second electrode leads 10 may be arranged alternately, and adjacent first electrode leads 8 and second electrode leads 10 may be electrically connected. That is, a plurality of electrode bodies 2 may be connected in series in each energy storage device 1. Furthermore, two adjacent energy storage devices 1 may be connected in series. Furthermore, all of the electrode bodies 2 mounted on the energy storage module 100 may be connected in series.

[0050] Furthermore, the first electrode lead 8 and the second electrode lead 10 may protrude to the same side in the axial direction A. This allows the electrode bodies 2 to be electrically connected simply by arranging a bus bar on only one side of the energy storage module 100. This allows the number of steps required to assemble the energy storage module 100 to be reduced.

[0051] As described above, the energy storage module 100 according to this embodiment includes an energy storage device 1 and a holder 104 that holds the energy storage device 1. The energy storage device 1 includes a plurality of cylindrical electrode assemblies 2, a plurality of housing sections 12 that individually encase the plurality of electrode assemblies 2, and a film exterior body 4 that has sealing sections 14 that seal each of the housing sections 12 and connect the plurality of housing sections 12 to one another. The holder 104 has side plates 112 that extend in the arrangement direction A of the plurality of electrode assemblies 2. The side plates 112 have a plurality of recesses 112a that are aligned in the arrangement direction B and into which the housing sections 12 fit, a first edge 112c and a second edge 112d that are aligned in the axial direction A and extend in the arrangement direction B, and a third edge 112e and a fourth edge 112f that are aligned in the arrangement direction B and extend in the axial direction A. The holder 104 also has a first wall plate 144 that is formed from a part of the member that constitutes the side plate 112 and that protrudes in the orthogonal direction C from at least a partial area of ​​the first edge portion 112c.

[0052] The energy storage device 1 is long in the arrangement direction B, and the film exterior body 4 is highly flexible. For this reason, when the energy storage device 1 receives an external impact or the like, the center portion in the arrangement direction B is likely to bend so that it protrudes in the orthogonal direction C relative to both end portions. Furthermore, since the energy storage device 1 is long in the arrangement direction B, the side plates 112 are also long in the arrangement direction B. Furthermore, from the perspective of reducing the weight of the energy storage module 100, it is required that the thickness of the side plates 112 be made as thin as possible. Therefore, like the energy storage device 1, the side plates 112 are also likely to bend so that their center portions in the arrangement direction B protrude in the orthogonal direction C. In particular, the side plates 112 have a plurality of recesses 112a aligned in the arrangement direction B, which makes them more likely to bend.

[0053] In contrast, the holder 104 of the present embodiment has a first wall plate 144 that protrudes from the first edge portion 112c of the side plate 112 in the orthogonal direction C. This increases the rigidity of the holder 104 against the above-mentioned bending. This increases the holding strength of the energy storage device 1. Furthermore, it is possible to effectively reduce stress generated in the holder 104, thereby increasing the rigidity of the energy storage module 100.

[0054] Furthermore, compared to when the same rigidity is obtained by increasing the thickness of the side plate 112, an increase in the weight of the energy storage module 100 can be suppressed. Therefore, it is possible to easily achieve both improved rigidity and weight reduction of the energy storage module 100. Furthermore, the first wall plate 144 is molded integrally with the side plate 112. This improves the reliability of the connection between the side plate 112 and the first wall plate 144 compared to when a separate member for reinforcing the holder 104 is adhered to the holder 104.

[0055] Moreover, the side plate 112 of this embodiment has a plurality of recesses 112a, and each accommodation section 12 fits into each recess 112a. This allows the energy storage devices 1 to be held more stably. Therefore, the electrical connection between each energy storage device 1 and the bus bar can be more stably maintained, and damage to each energy storage device 1 can be further suppressed. This improves the power generation performance and safety performance of the energy storage module 100. Furthermore, because the plurality of electrode bodies 2 are sealed in the film exterior body 4 to form a pouch structure, the weight of the energy storage module 100 can be reduced compared to when each electrode body 2 is individually sealed in an exterior can.

[0056] Moreover, the holder 104 of this embodiment has a second wall plate 146 that is formed from a part of the member that constitutes the side plate 112 and that protrudes from at least a part of the second edge portion 112d in the orthogonal direction C. This can further increase the rigidity of the holder 104.

[0057] Furthermore, the holder 104 of this embodiment has a third wall plate 148 that is formed from a part of the member that constitutes the side plate 112, protrudes from at least a portion of the third edge portion 112e in the orthogonal direction C, and is connected to the first wall plate 144. This further increases the rigidity of the holder 104. Furthermore, the third wall plate 148 of this embodiment is connected not only to the first wall plate 144 but also to the second wall plate 146. This further increases the rigidity of the holder 104. Note that it is sufficient for the third wall plate 148 to be connected to at least one of the first wall plate 144 and the second wall plate 146. Connecting the third wall plate 148 to both the first wall plate 144 and the second wall plate 146 provides an even greater rigidity improvement effect, but connecting the third wall plate 148 to at least one of the first wall plate 144 and the second wall plate 146 provides at least a slight rigidity improvement effect.

[0058] The holder 104 of this embodiment also has a fourth wall plate 150 that is formed from part of the components that make up the side plate 112, protrudes from at least a portion of the fourth edge 112f in the orthogonal direction C, and is connected to the first wall plate 144. This further increases the rigidity of the holder 104. The fourth wall plate 150 of this embodiment is connected not only to the first wall plate 144 but also to the second wall plate 146. This further increases the rigidity of the holder 104. The fourth wall plate 150 only needs to be connected to at least one of the first wall plate 144 and the second wall plate 146. Connecting the fourth wall plate 150 to both the first wall plate 144 and the second wall plate 146 provides an even greater rigidity improvement effect, but connecting the fourth wall plate 150 to at least one of the first wall plate 144 and the second wall plate 146 provides at least a slight rigidity improvement effect.

[0059] The holder 104 of this embodiment also has a first wall plate 144 protruding in the orthogonal direction C from the first edge 112c, a second wall plate 146 protruding in the orthogonal direction C from the second edge 112d, a third wall plate 148 protruding in the orthogonal direction C from the third edge 112e, and a fourth wall plate 150 protruding in the orthogonal direction C from the fourth edge 112f. The first wall plate 144, the second wall plate 146, the third wall plate 148, and the fourth wall plate 150 are formed as part of the components that make up the side plate 112. The side plate 112 is entirely surrounded by the first wall plate 144, the second wall plate 146, the third wall plate 148, and the fourth wall plate 150. This further increases the rigidity of the holder 104.

[0060] The energy storage module 100 of this embodiment includes multiple energy storage devices 1. At least a portion of the side plate 112 has a corrugated shape with repeated recesses and protrusions in the arrangement direction B. The multiple recesses 112a are provided in the corrugated portion and are sandwiched between two energy storage devices 1. When viewed from one main surface, each of the accommodation sections 12 of one energy storage device 1 fits into each of the recesses 112a, and when viewed from the main surface, each of the accommodation sections 12 of the other energy storage device 1 fits into each of the protrusions 112b, from the back surface. This further improves the stability of each energy storage device 1 in the energy storage module 100. Furthermore, when a portion of the side plate 112 is corrugated, the volume of the portion of the side plate 112 where the recesses 112a are formed can be reduced. This allows the holder 104 to be made lighter. Furthermore, the multiple recesses 112a can be formed by pressing a raw material such as a metal plate.

[0061] Furthermore, the first edge portion 112c of this embodiment has a flat portion extending in the arrangement direction B. The first wall plate 144 is bent and protrudes from one end of this flat portion in the axial direction A. This configuration makes it easier to manufacture the holder 104 than when there is no flat portion of the first edge portion 112c between the multiple recesses 112a and the first wall plate 144, that is, when the first wall plate 144 is formed directly on the end of a corrugated plate. In particular, when manufacturing the holder 104 by bending a metal plate using press working or the like, the holder 104 can be manufactured more easily. This improves the reliability and yield of manufacturing the holder 104.

[0062] Furthermore, second edge portion 112d in this embodiment has a flat plate-like portion extending in arrangement direction B. Second wall plate 146 is bent and protrudes from one end of this flat plate-like portion in axial direction A. This configuration facilitates the manufacture of holder 104 for the same reasons as when first edge portion 112c has a flat plate-like portion, and can improve the reliability and yield when manufacturing holder 104.

[0063] Furthermore, the film exterior body 4 of the present embodiment bends or curves between adjacent housing sections 12 and meanders in the arrangement direction B. This allows the length of the energy storage device 1 to be shorter than when the film exterior body 4 is not folded, without making the sealing section 14 smaller. As a result, it is possible to increase the number of electrode assemblies 2 mounted in the energy storage module 100, or to reduce the size of the energy storage module 100 without reducing the number of electrode assemblies 2 mounted. In other words, according to the present embodiment, it is possible to improve the energy density of the energy storage module 100 while suppressing a deterioration in the sealing performance of the electrode assemblies 2.

[0064] The first wall plate 144 and the second wall plate 146 may protrude from each edge of the side plate 112 to both sides in the orthogonal direction C. This structure also includes a structure in which each wall plate protrudes from each edge to one side in the orthogonal direction C and then folds back to protrude to the other side in the orthogonal direction C. The extension range of the first wall plate 144 and the second wall plate 146 in the orthogonal direction C is limited to the range sandwiched between the electrode leads of the two power storage devices 1 arranged on either side of the side plate 112. On the other hand, the larger the dimension of each wall plate in the orthogonal direction C, the more effectively it can suppress the above-mentioned deflection of the side plate 112. Therefore, by having the first wall plate 144 and the second wall plate 146 protrude to both sides in the orthogonal direction C, the dimension of the first wall plate 144 and the second wall plate 146 in the orthogonal direction C can be made larger than when they protrude only to one side. This makes it easier to suppress the deflection of the side plate 112.

[0065] Although the extension range of the third wall plate 148 and the fourth wall plate 150 is not limited by the electrode leads of the energy storage device 1, it is preferable that they protrude on both sides of the orthogonal direction C, similar to the first wall plate 144 and the second wall plate 146. This increases the connection area (cross-sectional area) with the first wall plate 144 and the second wall plate 146, and can further increase the rigidity of the holder 104.

[0066] The embodiments of the present disclosure have been described in detail above. The above-described embodiments merely illustrate specific examples of implementing the present disclosure. The content of the embodiments does not limit the technical scope of the present disclosure, and many design modifications, such as changing, adding, or deleting components, are possible within the scope of the invention defined in the claims. A new embodiment with design modifications will combine the effects of the combined embodiments and modifications. In the above-described embodiments, content that allows such design modifications is emphasized by using notations such as "in this embodiment" or "in this embodiment," but design modifications are also permitted even in content without such notation. Furthermore, any combination of components included in each embodiment is also valid as an aspect of the present disclosure. Hatching on cross sections in the drawings does not limit the material of the hatched object. [Explanation of symbols]

[0067] 1 Energy storage device, 2 Electrode body, 4 Film exterior body, 12 Storage section, 14 Sealing section, 100 Energy storage module, 104 Holder, 112 Side plate, 112a Recessed section, 112b Protruding section, 112c First edge section, 112d Second edge section, 112e Third edge section, 112f Fourth edge section, 144 First wall plate, 146 Second wall plate, 148 Third wall plate, 150 Fourth wall plate.

Claims

1. a power storage device; a holder that holds the electricity storage device, The power storage device is A plurality of cylindrical electrode bodies; a film exterior body having a plurality of housing sections that individually encase the plurality of electrode assemblies, and a sealing section that seals each housing section and connects the plurality of housing sections to one another, The holder is a side plate extending in an arrangement direction of the plurality of electrode assemblies, the side plate having a plurality of recesses aligned in the arrangement direction into which the respective accommodating portions fit, a first edge portion and a second edge portion aligned in an axial direction of the electrode assemblies and extending in the arrangement direction, and a third edge portion and a fourth edge portion aligned in the arrangement direction and extending in the axial direction; a first wall plate formed as part of a member constituting the side plate and protruding from at least a part of the first edge portion in a direction perpendicular to the axial direction and the arrangement direction; Energy storage module.

2. the holder includes a second wall plate formed of a part of the member constituting the side plate and protruding in the orthogonal direction from at least a part of the second edge portion; The energy storage module according to claim 1 .

3. the holder is formed of a part of a member constituting the side plate, and has a third wall plate that protrudes in the orthogonal direction from at least a part of the third edge portion and is connected to the first wall plate. The energy storage module according to claim 1 or 2.

4. the holder includes a third wall plate that is formed from a part of a member that constitutes the side plate, protrudes in the orthogonal direction from at least a part of the third edge portion, and is connected to at least one of the first wall plate and the second wall plate; The energy storage module according to claim 2 .

5. the holder includes a fourth wall plate that is formed from a part of a member that constitutes the side plate, protrudes from at least a part of the fourth edge portion in the orthogonal direction, and is connected to the first wall plate. The energy storage module according to claim 1 .

6. the holder includes a fourth wall plate that is formed from a part of a member that constitutes the side plate, protrudes in the orthogonal direction from at least a part of the fourth edge portion, and is connected to at least one of the first wall plate and the second wall plate; The energy storage module according to claim 2 or 4.

7. the holder has a first wall panel protruding in the perpendicular direction from the first edge, a second wall panel protruding in the perpendicular direction from the second edge, a third wall panel protruding in the perpendicular direction from the third edge, and a fourth wall panel protruding in the perpendicular direction from the fourth edge, the first wall plate, the second wall plate, the third wall plate, and the fourth wall plate are formed as part of the members constituting the side plates, The side plate is entirely surrounded by the first wall plate, the second wall plate, the third wall plate, and the fourth wall plate. The energy storage module according to claim 1 .

8. the power storage module includes a plurality of the power storage devices, at least a portion of the side plate has a corrugated shape with repeated concave and convex portions in the arrangement direction, and the plurality of concave portions are provided in the corrugated portion and are sandwiched between two of the power storage devices; Each of the storage portions of one of the power storage devices is fitted into each of the recesses when viewed from one main surface side, and each of the storage portions of the other of the power storage devices is fitted from the back surface side into each of the protrusions when viewed from the main surface side. The energy storage module according to claim 1 .

9. the first edge portion includes a flat plate-shaped portion extending in the arrangement direction, The first wall plate is bent and protrudes from one end of the flat plate portion in the axial direction. The power storage module according to claim 8 .

10. the holder has a second wall plate formed of a part of the member constituting the side plate and protruding in the orthogonal direction from at least a part of the second edge portion; the second edge portion includes a flat plate-shaped portion extending in the arrangement direction, The second wall plate is bent and protrudes from one end of the flat plate-shaped portion in the axial direction. The power storage module according to claim 8 .

11. The film exterior body bends or curves between adjacent storage sections and meanders in the arrangement direction. The energy storage module according to claim 1 .

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