JP2019204669A - Power storage device - Google Patents

Abstract

To provide a power storage device capable of suppressing deformation of an overhang portion of a power storage module. In the electricity storage device 1, since the thick film portion 26 is provided in the overhang portion 24 of the electricity storage module 4, in one electricity storage module 4, the internal pressure of the electrode laminate 11 increases and the overhang portion 24 is laminated. The thick film portion 26 of the overhang portion 24 of the electricity storage module 4 abuts the thick film portion 26 of the overhang portion 24 of another adjacent electricity storage module 4 in a state of being deformed outward in the direction D1. After the thick film portions 26 are brought into contact with each other, the overhang portion 24 is prevented from being further deformed. Therefore, according to power storage device 1, it is possible to allow the deformation of overhang portion 24 to some extent at the initial stage of deformation, while suppressing excessive deformation of overhang portion 24. [Selection diagram] Fig. 5

Description

  The present invention relates to a power storage device.

  2. Description of the Related Art Conventionally, a so-called bipolar power storage module including a bipolar electrode in which a positive electrode is provided on one surface of an electrode plate and a negative electrode is provided on the other surface is known (see Patent Document 1). Such a power storage module includes an electrode stack in which a plurality of bipolar electrodes are stacked. A sealing body that seals between adjacent bipolar electrodes is provided on a side surface of the electrode stack.

JP 2011-204386 A

  It is conceivable to configure a power storage device by stacking a plurality of power storage modules as described above with a conductive member interposed therebetween. By the way, in the electrical storage module as described above, the internal pressure of the electrode stack may increase depending on usage conditions and the like. In this case, if the sealing body has an overhang portion that wraps around from the side surface side of the electrode stack to the end surface side in the stacking direction, the overhang portion may be deformed to the outside in the stacking direction.

  An object of this invention is to provide the electrical storage apparatus which can suppress a deformation | transformation of the overhang part of an electrical storage module.

  A power storage device according to one aspect of the present invention is interposed between a plurality of power storage modules stacked along a predetermined stacking direction and between power storage modules adjacent in the stacking direction and in both the adjacent power storage modules. And a plurality of conductive members having flow paths extending in a direction intersecting with the stacking direction, and the power storage module includes an electrode stack in which a plurality of bipolar electrodes are stacked via separators along the stacking direction. And a sealing body that is provided on the side surface of the electrode stack and has a frame shape and seals between adjacent bipolar electrodes, and the sealing body is an electrode in the stacking direction from the side of the electrode stack. An overhang portion that wraps around the end surface of the laminate and surrounds the periphery of the conductive member when viewed from the stack direction, and the overhang portion has a thickness in the stack direction. Thick film portion than the thickness of the other portion of the Bahangu portion.

  In the power storage device, since the thick film portion is provided in the overhang portion of the sealing body of the power storage module, the internal pressure of the electrode stack increases in one power storage module and the overhang portion is deformed to the outside in the stacking direction. In the situation, the thick film portion of the overhang portion of the power storage module comes into contact with the overhang portion of another adjacent power storage module. After the thick film portion abuts, the overhang portion is prevented from further deformation. Therefore, according to the power storage device, deformation of the overhang portion can be suppressed.

  In the power storage device according to another aspect, the overhang portion includes a first portion facing the end portion of the flow path of the conductive member and a second portion not facing the end portion, and the thick film portion is the first portion. It is provided in at least one of the part and the second part.

  In the power storage device according to another aspect, the conductive member has a rectangular shape including a pair of the first side and a pair of the second side when viewed from the stacking direction, and the flow path is parallel to the first side. The overhang portion has a rectangular ring shape surrounding the periphery of the conductive member when viewed from the stacking direction, the first portion extends in parallel with the second side of the conductive member, and the second portion is the second portion of the conductive member. It extends parallel to one side.

  In the power storage device according to another aspect, the thick film portion is a strip-shaped thick film portion provided over the entire length of the second portion.

  In the power storage device according to another aspect, the thick film portion is a plurality of protruding thick film portions provided side by side in at least one of the first portion and the second portion.

  In the power storage device according to another aspect, the thick film portions are provided at positions facing the overhang portions of the power storage modules adjacent in the stacking direction.

  In the power storage device according to another aspect, the thick film portions provided at the opposing positions of the overhang portions of the power storage modules adjacent in the stacking direction are in contact with each other. In this case, since the thick film portions are in contact with each other before the overhang portion is deformed, the deformation of the overhang portion can be suppressed from the initial deformation.

  In the power storage device according to another aspect, the thick film portions provided at the opposing positions of the overhang portions of the adjacent power storage modules in the stacking direction are separated from each other. In this case, excessive deformation of the overhang portion can be suppressed while allowing the deformation of the overhang portion to some extent at the initial stage of deformation.

  In the power storage device according to another aspect, the distance between the thick film portions is shorter than the thickness of the conductive member in the stacking direction.

  In the power storage device according to another aspect, the sealing body includes a plurality of primary sealing bodies provided at the edges of the plurality of bipolar electrodes, and a secondary sealing body that surrounds the plurality of primary sealing bodies from the outside. And the overhang part is a part of the secondary sealing body.

  ADVANTAGE OF THE INVENTION According to this invention, the electrical storage apparatus which can suppress a deformation | transformation of the overhang part of an electrical storage module is provided.

It is sectional drawing which shows the electrical storage apparatus which concerns on one Embodiment. It is sectional drawing which shows the electrical storage module shown by FIG. It is the figure which showed the lamination | stacking state of the electrical storage module shown in FIG. 1, and a conductive plate. It is the figure which showed the air cooling of the electrically-conductive board shown by FIG. It is the principal part enlarged view which showed the thick film part in the overhang part of the electrical storage module shown by FIG. It is the figure which showed the thick film part in the (a) long side part of the overhang part of the electrical storage module shown in FIG. 5, and the thick film part in the (b) short side part. It is sectional drawing which shows the mode at the time of the internal pressure rise of the conventional electrical storage module.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are used for the same or corresponding elements, and duplicate descriptions are omitted.
[Configuration of power storage device]

  The power storage device 1 shown in FIG. 1 is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage device 1 includes a power storage module stack 2 and a restraining member 3.

  The power storage module laminate 2 includes a plurality (three in the present embodiment) of power storage modules 4 and a plurality (four in the present embodiment) of conductive plates (conductive members) 5. The plurality of power storage modules 4 are stacked along a predetermined stacking direction D1. The power storage module 4 is a bipolar battery including a bipolar electrode 14 described later. The power storage module 4 has, for example, a rectangular shape when viewed from the stacking direction D1. The power storage module 4 is, for example, a secondary battery such as a nickel hydride secondary battery or a lithium ion secondary battery, or an electric double layer capacitor. In the following description, a case where the power storage module 4 is a nickel metal hydride secondary battery will be exemplified.

  The plurality of conductive plates 5 are respectively interposed between the power storage modules 4 and 4 adjacent to each other in the stacking direction D1, and are disposed on both sides of the plurality of power storage modules 4 in the stacking direction D1. A positive electrode terminal 6 is electrically connected to the conductive plate 5 arranged on one side in the stacking direction D1 with respect to the plurality of power storage modules 4. A negative electrode terminal 7 is electrically connected to the conductive plate 5 disposed on the other side in the stacking direction D1 with respect to the plurality of power storage modules 4. For example, the positive electrode terminal 6 and the negative electrode terminal 7 are drawn from the edge of the conductive plate 5 in a direction orthogonal to the stacking direction D1. The power storage device 1 is charged and discharged by the positive electrode terminal 6 and the negative electrode terminal 7.

  The restraining member 3 includes a pair of end plates 8A and 8B that sandwich the power storage module stack 2 in the stacking direction D1, applies a restraining load to the power storage module stack 2, and a fastening bolt B that fastens the end plates 8A and 8B together. Nut N. Each end plate 8A, 8B is formed in a rectangular shape by, for example, metal. When viewed from the stacking direction D <b> 1, the outer edges of the end plates 8 </ b> A and 8 </ b> B are located outside the outer edge of the power storage module 4.

  Each end plate 8 </ b> A, 8 </ b> B is provided with an insertion hole 8 a in a portion located outside the power storage module stack 2 when viewed from the stacking direction D <b> 1. The fastening bolt B is passed from the insertion hole 8a of the other end plate 8B in the stacking direction D1 toward the insertion hole 8a of the one end plate 8A. A nut N is screwed onto the tip of the fastening bolt B protruding from the insertion hole 8a of the end plate 8A. As a result, the power storage module 4 and the conductive plate 5 are sandwiched between the end plates 8A and 8B to be unitized as the power storage module stack 2, and a restraining load is applied to the power storage module stack 2 in the stacking direction D1. Yes. Hereinafter, when the end plates 8A and 8B are not distinguished from each other, they may be collectively referred to as the end plate 8.

The power storage device 1 further includes a pair of insulating members 9A and 9B. The insulating members 9A and 9B are interposed between the end plates 8A and 8B and the conductive plate 5 adjacent to the end plates 8A and 8B, respectively. The insulating members 9A and 9B electrically insulate between the end plates 8A and 8B and the conductive plate 5, respectively. Each of the insulating members 9A and 9B is made of, for example, a resin having electrical insulation. The insulating members 9A and 9B are provided, for example, on the inner surfaces of the end plates 8A and 8B (the surface on the power storage module laminate 2 side). Hereinafter, when the insulating members 9A and 9B are not distinguished from each other, they may be collectively referred to as the insulating member 9.
[Configuration of power storage module]

  As shown in FIG. 2, the power storage module 4 includes an electrode stack 11 and a sealing body 12 that seals the electrode stack 11. The electrode laminate 11 is configured by laminating a plurality of bipolar electrodes 14 with a separator 13 interposed therebetween. In the present embodiment, the stacking direction of the electrode stack 11 coincides with the stacking direction D1 of the power storage module stack 2. The electrode stack 11 has a side surface 11 a formed by stacking bipolar electrodes 14.

  Each bipolar electrode 14 includes an electrode plate 15, a negative electrode 16 provided on one surface 15 a of the electrode plate 15, and a positive electrode 17 provided on the other surface 15 b of the electrode plate 15. The negative electrode 16 is a negative electrode active material layer formed by applying a negative electrode active material. The positive electrode 17 is a positive electrode active material layer formed by coating a positive electrode active material. In the electrode stack 11, the negative electrode 16 of one bipolar electrode 14 is opposed to the positive electrode 17 of one bipolar electrode 14 adjacent in the stacking direction D <b> 1 via the separator 13. The positive electrode 17 of the one bipolar electrode 14 is opposed to the negative electrode 16 of the other bipolar electrode 14 adjacent in the stacking direction D1 with the separator 13 interposed therebetween.

  In the electrode laminate 11, a positive electrode termination electrode 18 is disposed at one end in the lamination direction D1. In the electrode laminate 11, a negative electrode termination electrode 19 is disposed at the other end in the lamination direction D1. The positive electrode termination electrode 18 includes an electrode plate 15 and a positive electrode 17 provided on the other surface 15 b of the electrode plate 15. The positive electrode 17 of the positive electrode termination electrode 18 opposes the negative electrode 16 of the bipolar electrode 14 disposed at one end in the stacking direction D1 with the separator 13 interposed therebetween. The negative electrode termination electrode 19 includes an electrode plate 15 and a negative electrode 16 provided on one surface 15 a of the electrode plate 15. The negative electrode 16 of the negative electrode termination electrode 19 is opposed to the positive electrode 17 of the bipolar electrode 14 disposed at the other end in the stacking direction D1 via the separator 13.

  The electrode plate 15 is made of, for example, a metal foil made of nickel or a nickel-plated steel plate, and is formed in a rectangular shape. The region on the edge 15c in the electrode plate 15 is an uncoated region where the positive electrode active material and the negative electrode active material are not coated. Examples of the negative electrode active material constituting the negative electrode 16 include a hydrogen storage alloy. An example of the positive electrode active material constituting the positive electrode 17 is nickel hydroxide.

The separator 13 is formed in a sheet shape, for example. Examples of the separator 13 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric or a nonwoven fabric made of polypropylene, polyethylene terephthalate (PET), methylcellulose, and the like. The separator 13 may be reinforced with a vinylidene fluoride resin compound. The separator 13 is not limited to a sheet shape, and may be formed in a bag shape.
[Detailed configuration of conductive plate]

  As shown in FIGS. 3 and 4, each conductive plate 5 has a rectangular shape when viewed from the stacking direction D1. In the present embodiment, each conductive plate 5 has a rectangular shape composed of a pair of short sides (first sides) and a pair of long sides (second sides) when viewed from the stacking direction D1. .

  In a state where each conductive plate 5 is positioned between adjacent power storage modules 4 in the stacking direction D1, as shown in FIG. The electrode plate 15 of the negative electrode termination electrode 19 of the power storage module 4 on the side is in contact. Therefore, the conductive plate 5 has a function as a connecting member that electrically connects the power storage modules 4 and 4 adjacent in the stacking direction D1 in series.

Inside each conductive plate 5, a plurality of linear flow paths 5 a for circulating the refrigerant are provided. Air is used as the refrigerant in the present embodiment. Each flow path 5 a extends and penetrates so as to be parallel to the short side of the conductive plate 5. The conductive plate 5 is arranged so that its short side is parallel to the blowing direction D3. In this embodiment, the blowing direction D3 is a direction orthogonal to the stacking direction D1 and the drawing direction D2 from which the positive electrode terminal 6 and the negative electrode terminal 7 are drawn. As shown in FIG. 4, a blower (or a blower port) 30 that sends cooling air to the power storage device 1 is positioned on the upstream side of the cooling air sent along the air blowing direction D <b> 3. The cooling air sent from the blower 30 enters the flow path 5a from each end opening of the plurality of flow paths 5a arranged along the long side of the conductive plate 5, and passes through the flow path 5a. Thus, the conductive plate 5 also has a function as a heat radiating member that radiates heat generated in the power storage module 4 by flowing cooling air into the flow path 5a.
[Detailed structure of sealed body]

  The sealing body 12 is provided on the side surface 11 a of the electrode laminate 11 and includes a plurality of primary sealing bodies 21 and one secondary sealing body 22. The sealing body 12 is made of a resin material such as polypropylene (PP), polyphenylene sulfide (PPS), or modified polyphenylene ether (modified PPE). In the present embodiment, the sealing body 12 has a rectangular frame shape as shown in FIG. More specifically, the sealing body 12 has a rectangular shape composed of a pair of long sides parallel to the drawing direction D2 and a pair of short sides parallel to the blowing direction D3. A plurality of (four in this example) attachment portions 25 for attaching safety valves (not shown) are provided in a portion corresponding to the short side of the sealing body 12. Each attachment part 25 is comprised by the some through-hole extended along the drawer direction D2, for example.

  The primary sealing bodies 21 are respectively provided on the edge 15c of the electrode plate 15 (edge of the bipolar electrode 14). The primary sealing body 21 is formed into a rectangular frame shape by, for example, resin injection molding, and is firmly bonded to the edge portion 15c of the electrode plate 15 by welding using ultrasonic waves or heat. For example, the primary sealing body 21 protrudes from the edge 15c in a direction orthogonal to the stacking direction D1, and is embedded in the secondary sealing body 22 in the protruding portion.

  The secondary sealing body 22 is provided so as to surround the entire primary sealing body 21 from the outside. The secondary sealing body 22 is formed in a rectangular frame shape by, for example, resin injection molding, and is welded to the outer surface of the primary sealing body 21 by heat at the time of injection molding. The secondary sealing body 22 seals between the bipolar electrodes 14 and 14 adjacent in the stacking direction D1. Thus, an internal space V is formed between the bipolar electrodes 14 and 14 adjacent in the stacking direction D1. In the internal space V, an electrolytic solution E made of an alkaline solution such as an aqueous potassium hydroxide solution is accommodated.

  The secondary sealing body 22 has a pair of overhangs covering a frame portion 23 extending along the side surface 11a of the electrode stack 11 and a part of each of the upper and lower end surfaces 11b (that is, outer edge portions) of the electrode stack 11. Part 24. In the secondary sealing body 22, the frame portion 23 and the overhang portion 24 are provided integrally and continuously, and are provided so as to go from the side surface 11 a side to the end surface 11 b side of the electrode stack 11.

  The frame portion 23 has a rectangular frame shape extending along the side surface 11 a of the electrode laminate 11, and holds the protruding portion of the primary sealing body 21. The upper surface overhang portion 24A of the pair of overhang portions 24 protrudes from the upper end of the frame portion 23 in the stacking direction D1 so as to extend toward the center side of the electrode stack 11 when viewed from the stack direction D1. And has a bowl-shaped cross section as shown in FIG. The upper surface overhang portion 24 </ b> A covers at least a part of the primary sealing body 21 disposed at the upper end of the electrode stack 11, and the edge of the upper end surface 11 b of the electrode stack 11 via the primary sealing body 21. Is facing. Similarly, the lower surface overhang portion 24B of the pair of overhang portions 24 extends from the lower end of the frame portion 23 in the stacking direction D1 toward the center side of the electrode stack 11 when viewed from the stacking direction D1. And has a bowl-shaped cross section as shown in FIG. The lower surface overhang portion 24 </ b> B covers at least a part of the primary sealing body 21 disposed at the lower end of the electrode stack 11 and covers the edge of the lower end surface 11 b of the electrode stack 11.

  The upper surface overhang portion 24A and the lower surface overhang portion 24B extend along a plane perpendicular to the stacking direction D1, and have the same shape when viewed from the stacking direction D1. In the present embodiment, each overhang portion 24 has a rectangular ring shape as shown in FIGS. More specifically, each overhang portion 24 includes a pair of strip-like long side portions 24a (first portion) extending parallel to the long side of the conductive plate 5 (that is, parallel to the drawing direction D2), and conductive It presents a rectangular ring consisting of a pair of strip-like short side portions 24b (second portions) extending parallel to the short sides of the plate 5 (that is, parallel to the blowing direction D3). The rectangular annular width of each overhang portion 24 can be designed to be equal. The other power storage modules 4 constituting the power storage module stack 2 also have overhang portions 24 of the same size and shape, and the overhang portions 24 of adjacent power storage modules 4 in the stacking direction D1 are stacked in the stacking direction D1. Are opposed to each other.

  As shown in FIG. 4, the inner edge of the overhang portion 24 is designed to have a dimension larger than the outer dimension of the conductive plate 5 described above. In addition, the power storage module 4 and the conductive plate 5 are aligned so that the conductive plate 5 fits inside the overhang portion 24 when they are superimposed on each other. Therefore, when viewed from the stacking direction D <b> 1, the overhang portion 24 surrounds the periphery of the conductive plate 5, and the conductive plate 5 is not obstructed by the overhang portion 24, and the electrode plate of the positive electrode termination electrode 18 of the power storage module 4. 15 and the electrode plate 15 of the negative terminal electrode 19. At this time, the long side part 24a of each overhang part 24 opposes the edge part opening of the flow path 5a of the electrically conductive plate 5, and the short side part 24b does not oppose the edge part opening of the flow path 5a.

  Next, the thick film portion of the overhang portion 24 will be described with reference to FIGS.

  The overhang portion 24 has a thick film portion 26 whose thickness in the stacking direction D1 is thicker than the thickness of other portions of the overhang portion 24. In the present embodiment, the overhang portion 24 in the portion other than the thick film portion 26 is designed to have the same thickness that is thinner than the thickness of the thick film portion 26. In the present embodiment, as shown in FIG. 5, the thick film portion 26 protrudes from a part of the overhang portion 24 to the outside in the stacking direction D1. That is, the upper surface overhang portion 24A is provided with an upper surface thick film portion 26A that protrudes upward along the stacking direction D1, and the lower surface overhang portion 24B is provided with the lower surface thick film portion 26B that protrudes downward along the stacking direction D1. Is provided. The upper thick film portion 26A and the lower thick film portion 26B are aligned with each other and face each other with a predetermined distance d. In the present embodiment, the separation distance d between the upper thick film portion 26A and the lower thick film portion 26B is designed to be shorter than the thickness of the conductive plate 5 (that is, the length in the stacking direction D1).

  In the long side portion 24a of the overhang portion 24, as shown in FIG. 6A, the thick film portion 26 is a plurality of protruding thick film portions that are regularly arranged. In the present embodiment, each protruding thick film portion 26 is provided so as to be shifted from the position of the end opening of the flow channel 5a so that the protruding thick film portion 26 does not block the end opening of the flow channel 5a as much as possible. Is provided. The thick film portions 26 are not necessarily arranged regularly, and may be irregularly arranged as long as the adjacent thick film portions 26 are separated from each other. The protruding thick film portion 26 may have a columnar shape such as a cylinder or a prism, or a frustum shape such as a truncated cone. In the long side portion 24a of the overhang portion 24, a thickness in the stacking direction D1 is secured as shown in FIG. 6A in order to secure a passage of cooling air flowing from the blower 30 to the end opening of the flow path 5a. In the overhang portion 24, the thinnest thin film portion 28 is provided between the adjacent protruding thick film portions 26.

  In the short side part 24b of the overhang part 24, as shown in FIG.6 (b), the thick film part 26 is a strip | belt-shaped thick film part provided over the full length of the short side part 24b. The strip-shaped thick film portion 26 can also be composed of a plurality of continuous strip-shaped thick film portions.

In the present embodiment, the thick film portion 26 is made of the same material as the overhang portion 24 and is formed integrally with the overhang portion 24. That is, when the secondary sealing body 22 is formed by resin injection molding, the overhang portion 24 and the thick film portion 26 are integrally formed. At this time, the thick film portion 26 can be easily formed by providing a depression corresponding to the shape of the thick film portion 26 in the injection mold.
[Effect]

  Here, in the conventional power storage module, the deformation of the overhang portion that may occur when the internal pressure increases is described.

  In the conventional power storage module 40, when the internal pressure of the electrode stack 11 increases due to usage conditions or the like, the overhang 24 may be deformed outward in the stacking direction D1, as shown in FIG. This is because the electrode stack 11 is deformed so as to swell in the stacking direction D1 due to an increase in internal pressure, and the central portion of the electrode stack 11 when viewed from the stacking direction D1 is greatly deformed compared to the edge. It is. As a result, in the overhang portion 24, the distal end portion on the side far from the frame portion 23 is deformed with the base end portion on the side close to the frame portion 23 as the base point, and another overhang portion 24 facing away from the electrode stack 11. Get closer to.

  If the deformation of the overhang portion 24 becomes large, for example, a crack or break may occur at the base end portion of the overhang portion 24 and the sealing body 12 may be damaged. Alternatively, there may be a gap between the sealing body 12 and the bipolar electrode 14. Furthermore, there is a possibility that the electrode plate 15 of the positive electrode termination electrode 18 and the negative electrode termination electrode 19 of the electrode laminate 11 may be cracked or broken. As a result, leakage of the electrolytic solution E accommodated in the electrode laminate 11 is considered to occur.

  In the power storage device 1 described above, since the thick film portion 26 is provided in the overhang portion 24 of the power storage module 4, the internal pressure of the electrode stack 11 rises in one power storage module 4 and the overhang portion 24 is stacked in the stacking direction D1. In this situation, the thick film portion 26 of the overhang portion 24 of the power storage module 4 contacts the thick film portion 26 of the overhang portion 24 of another adjacent power storage module 4. After the thick film portions 26 come into contact with each other, the overhang portion 24 can be prevented from further deformation. Therefore, according to the power storage device 1, excessive deformation of the overhang portion 24 can be suppressed while allowing deformation of the overhang portion 24 to some extent in the initial stage of deformation.

  The distance d between the upper thick film portion 26A and the lower thick film portion 26B can be adjusted according to the specifications of the power storage device 1, the dimensions of the power storage module 4, and the like. For example, the distance d can be designed to be long under conditions where the deformation of the overhang 24 can be allowed to some extent, and the distance d can be shortened under conditions where it is desired to suppress deformation of the overhang 24 as much as possible. Can be designed. The upper surface thick film portion 26A and the lower surface thick film portion 26B may be in contact with each other at the time of manufacturing the power storage device 1 (that is, before the internal pressure is increased). In this case, since the thick film portions 26 are in contact with each other before the overhang portion 24 is deformed, the deformation of the overhang portion 24 can be suppressed (theoretically preventing the deformation) from the initial deformation.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

  For example, the position and number of the thick film portions 26 can be changed as appropriate. By providing the thick film portion 26 in both the long side portion 24 a and the short side portion 24 b of the overhang portion 24, various deformations of the overhang portion 24 can be suppressed. The thick film portion 26 may be provided on either the long side portion 24 a or the short side portion 24 b of the overhang portion 24.

  With respect to the thick film portion 26 provided in the long side portion 24a, the long side portion 24a is located on the upstream side in the blowing direction D3 and faces the end opening of the flow path 5a of the conductive plate 5, so The position, size, and number of the thick film portions 26 can be adjusted so that the passage of the cooling air flowing in is sufficiently secured. When the flow path 5a is not provided in the conductive plate 5, a strip-like thick film portion may be provided over the entire length of the long side portion 24a of the overhang portion 24, and the strip-like thick film portion and the short side portion 24a of the long side portion 24a may be provided. You may provide the cyclic | annular thick film part 26 which consists of a strip | belt-shaped thick film part of the side part 24b.

  The thick film portion 26 provided on the short side portion 24b may be a plurality of protruding thick film portions that are regularly or irregularly arranged along the short side portion 24b instead of the belt-like thick film portion. By providing the strip-shaped thick film portion 26 in the short side portion 24b, it is possible to effectively suppress cooling air leakage due to the circulation of cooling air in addition to the flow path 5a of the conductive plate 5.

  Moreover, although the thick film part 26 demonstrated the aspect provided integrally with the overhang part 24, the aspect provided with a thick film part as a member different from the overhang part 24 of the secondary sealing body 22 may be sufficient. .

  Furthermore, the thick film portion 26 does not need to be provided in both of the overhang portions 24 facing each other, and may be provided in any one of the overhang portions 24. Even in such an aspect, when the internal pressure of the electrode stack 11 increases, the thick film portion 26 of the overhang portion 24 of the power storage module 4 abuts on the overhang portion 24 of another adjacent power storage module 4, thereby overhanging. The deformation of the portion 24 can be suppressed. In such an aspect, since it is not necessary to adjust the position so that the thick film portions face each other, the configuration of the power storage device 1 is simplified, and the power storage device 1 can be easily manufactured.

  DESCRIPTION OF SYMBOLS 1 ... Power storage device, 4 ... Power storage module, 5 ... Conductive plate, 5a ... Flow path, 11 ... Electrode laminated body, 12 ... Sealing body, 14 ... Bipolar electrode, 21 ... Primary sealing body, 22 ... Secondary sealing Body, 24 ... overhang portion, 26 ... thick film portion, D1 ... stacking direction, D2 ... drawing direction, D3 ... air blowing direction.

Claims (10)

A plurality of power storage modules stacked along a predetermined stacking direction;
A plurality of conductive members interposed between each of the adjacent power storage modules in the stacking direction and in contact with both of the adjacent power storage modules and having flow paths extending in a direction intersecting the stacking direction. Prepared,
The power storage module includes an electrode stack in which a plurality of bipolar electrodes are stacked via a separator along the stacking direction, and a frame shape provided on a side surface of the electrode stack, and between adjacent bipolar electrodes. A sealing body for sealing,
The sealing body extends from the side surface side of the electrode stack to the end face side of the electrode stack in the stacking direction, and exhibits an annular shape surrounding the periphery of the conductive member when viewed from the stacking direction. Including
The power storage device, wherein the overhang portion is provided with a thick film portion whose thickness in the stacking direction is thicker than the thickness of other portions of the overhang portion. The overhang portion has a first portion facing the end of the flow path of the conductive member and a second portion not facing the end;
The power storage device according to claim 1, wherein the thick film portion is provided in at least one of the first portion and the second portion. The conductive member has a rectangular shape composed of a first side pair and a second side pair when viewed from the stacking direction, and the flow path extends in parallel to the first side,
The overhang portion has a rectangular ring shape that surrounds the periphery of the conductive member when viewed from the stacking direction, the first portion extends parallel to a second side of the conductive member, and the second portion is the conductive portion. The power storage device according to claim 2, wherein the power storage device extends in parallel with the first side of the member.   The power storage device according to claim 3, wherein the thick film portion is a belt-like thick film portion provided over the entire length of the second portion.   The power storage device according to claim 3, wherein the thick film part is a plurality of protruding thick film parts provided side by side in at least one of the first part and the second part.   The power storage device according to any one of claims 1 to 5, wherein the thick film portions are respectively provided at positions facing the overhang portions of the power storage modules adjacent in the stacking direction.   The power storage device according to claim 6, wherein the thick film portions provided at positions facing each of the overhang portions of the power storage modules adjacent in the stacking direction are in contact with each other.   The power storage device according to claim 6, wherein the thick film portions provided at positions facing each of the overhang portions of the power storage modules adjacent in the stacking direction are separated from each other.   The power storage device according to claim 8, wherein a separation distance between the thick film portions is shorter than a thickness of the conductive member in the stacking direction. The sealing body has a plurality of primary sealing bodies provided respectively at edges of the plurality of bipolar electrodes, and a secondary sealing body surrounding the plurality of primary sealing bodies from the outside,
The power storage device according to claim 1, wherein the overhang portion is a part of the secondary sealing body.

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