JP7070279B2 - Power storage module - Google Patents

Description

The present invention relates to a power storage module.

Conventionally, as a power storage module, for example, as described in Japanese Patent Application Laid-Open No. 2005-5163, a plurality of bipolar electrodes are laminated to form a laminated body, and the side portion of the laminated body is sealed with a resin. Power storage modules are known.

Japanese Unexamined Patent Publication No. 2005-5163

In such a power storage module, as shown in FIG. 8, the side portion of the laminated body 102 in which the bipolar electrode 101 is laminated is sealed by the sealing body 103, and the end portion of the sealing body 103 is bent inward to overhang. It is conceivable to form the hang portion 103a. By extending the overhang portion 103a inside the laminated body 102, it is possible to suppress the spread of the end portion of the laminated body 102. However, when the power storage module is used, the internal pressure of the power storage module may increase. In this case, as shown in FIG. 9, an internal pressure may be applied to the overhang portion 103a of the sealing body 103 to cause deformation.

Therefore, an object of the present invention is to provide a power storage module capable of suppressing deformation of a sealed body that seals a laminated body.

That is, in the power storage module according to the present invention, which has a laminated body in which a plurality of electrodes are laminated and a sealed body is provided on the side surface of the laminated body, the sealed body has a side surface of the laminated body. It includes a main body portion that covers and an overhang portion that bends and extends inward of the laminated body at the end portion of the main body portion, and is projected from the surface of the overhang portion in the stacking direction of the laminated body to suppress deformation of the overhang portion. The overhang portion includes a portion overlapping the main body portion in the stacking direction and a portion extending inward of the laminated body, and the reinforcing portion is provided on the surface opposite to the surface facing the laminated body in the overhang portion. It is configured to extend from a portion overlapping the main body portion of the overhang portion to a portion extending inward of the laminated body . According to this power storage module, the bending rigidity of the overhang portion can be increased by forming the reinforcing portion in the overhang portion. Therefore, even if the internal pressure of the laminated body increases and the sealed body is pressed, the deformation of the sealed body can be suppressed. Further, since the bending rigidity of the overhang portion can be increased without increasing the entire overhang portion, it is possible to suppress the deformation of the sealed body while suppressing the increase in the weight of the sealed body. Further, by forming the reinforcing portion so as to extend from the portion overlapping the main body portion of the overhang portion to the portion extending inward of the laminated body, the bending rigidity of the overhang portion can be increased.

Further, in the power storage module according to the present invention, a plurality of reinforcing portions may be formed on the surface of the overhang portion at predetermined intervals along the forming direction of the side surface of the laminated body. In this case, by forming a plurality of reinforcing portions, the bending rigidity can be increased in a wide range in the overhang portion, and the deformation of the overhang portion can be appropriately suppressed.

Further, in the power storage module according to the present invention, the reinforcing portion may be formed with an inclined surface so that the protruding length on the tip end side of the overhang portion becomes small. In this case, the bending rigidity of the base end side of the overhang portion can be increased by forming an inclined surface on the reinforcing portion so that the protrusion length on the tip end side is smaller than that on the base end side of the overhang portion. Further, by reducing the protruding length of the reinforcing portion on the tip end side of the overhang portion, it is possible to suppress an increase in weight due to the formation of the reinforcing portion.
Further, in the power storage module according to the present invention, the reinforcing portion may be formed to have the same length as the length of the overhang portion.

According to the present invention, it is possible to suppress deformation of the sealed body that seals the laminated body.

It is the schematic sectional drawing of the power storage device using the power storage module which concerns on embodiment of this invention. It is a schematic sectional drawing which shows the internal structure of the power storage module which concerns on embodiment. It is a top view of the power storage module of FIG. It is explanatory drawing of the reinforcement part in the power storage module of FIG. It is explanatory drawing of the reinforcement part in the power storage module of FIG. It is a modification of the reinforcement part in the power storage module of FIG. It is a modification of the reinforcement part in the power storage module of FIG. It is explanatory drawing of the background technique. It is explanatory drawing of the background technique.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same or corresponding parts are designated by the same reference numerals, and duplicate description will be omitted.

FIG. 1 is a schematic cross-sectional view of a power storage device 1 using the power storage module 4 according to the present embodiment. The power storage device 1 shown in FIG. 1 shows an example of a power storage device using the power storage module 4, and is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage device 1 is constrained to the module stack 2 including the plurality of stacked power storage modules 4 and the stacking direction of the module stack 2 (here, the electrode stacking direction D in the electrode stack 11 described later). It is provided with a restraint member 3 for applying a load.

The module stack 2 includes a plurality of (here, three) power storage modules 4 and a plurality of (here, four) conductive plates 5. The power storage module 4 is a bipolar battery and has a rectangular shape when viewed from the stacking direction D. The power storage module 4 is, for example, a secondary battery such as a nickel hydrogen secondary battery or a lithium ion secondary battery, or an electric double layer capacitor. In the following description, a nickel-metal hydride secondary battery will be illustrated.

The storage modules 4 adjacent to each other in the stacking direction D are electrically connected to each other via the conductive plate 5. The conductive plates 5 are arranged between the storage modules 4 adjacent to each other in the stacking direction D and outside the stacking direction D of the storage modules 4 located at the stacking ends. A positive electrode terminal 6 is connected to one of the conductive plates 5 arranged outside the stacking direction D of the power storage module 4 located at the stacking end. The negative electrode terminal 7 is connected to the other conductive plate 5 arranged outside the stacking direction D of the power storage module 4 located at the stacking end. The positive electrode terminal 6 and the negative electrode terminal 7 are drawn out from the edge of the conductive plate 5, for example, in a direction intersecting the stacking direction D. The positive electrode terminal 6 and the negative electrode terminal 7 charge and discharge the power storage device 1.

Inside the conductive plate 5, a plurality of flow paths 5a through which a refrigerant such as air flows are provided. The flow path 5a extends along a direction intersecting (orthogonal) with, for example, the stacking direction D and the drawing directions of the positive electrode terminal 6 and the negative electrode terminal 7. The conductive plate 5 not only functions as a connecting member for electrically connecting the power storage modules 4 to each other, but also serves as a heat sink that dissipates heat generated by the power storage module 4 by circulating a refrigerant through these flow paths 5a. It also has a function. In the example of FIG. 1, the area of the conductive plate 5 seen from the stacking direction D is smaller than the area of the power storage module 4, but from the viewpoint of improving heat dissipation, the area of the conductive plate 5 is the area of the power storage module 4. It may be the same as the area, or may be larger than the area of the power storage module 4.

The restraint member 3 is composed of a pair of end plates 8 that sandwich the module laminate 2 in the stacking direction D, and fastening bolts 9 and nuts 10 that fasten the end plates 8 to each other. The end plate 8 is a rectangular metal plate having an area one size larger than the area of the power storage module 4 and the conductive plate 5 when viewed from the stacking direction D. A film F having electrical insulation is provided on the inner side surface of the end plate 8 in the stacking direction D (the surface facing the module laminated body 2 side). The film F insulates between the end plate 8 and the conductive plate 5.

The end plate 8 is provided with an insertion hole 8a at an edge portion on the outer peripheral side of the portion overlapping the module laminated body 2 in the stacking direction D. The fastening bolt 9 is passed from the insertion hole 8a of one end plate 8 toward the insertion hole 8a of the other end plate 8, and is attached to the tip portion of the fastening bolt 9 protruding from the insertion hole 8a of the other end plate 8. , The nut 10 is screwed. As a result, the power storage module 4 and the conductive plate 5 are sandwiched by the end plate 8 to be unitized as the module laminated body 2, and a restraining load is applied to the module laminated body 2 in the stacking direction D.

Next, the configuration of the power storage module 4 will be described in detail. FIG. 2 is a schematic cross-sectional view showing the internal configuration of the power storage module 4 shown in FIG. As shown in FIG. 2, the power storage module 4 has an electrode laminated body (laminated body) 11 in which a plurality of electrodes are laminated, and is configured by providing a sealing body 12 on the outer edge of the electrode laminated body 11. .. The electrode laminate 11 has a plurality of electrodes laminated along the stacking direction D via the separator 13 and the separator 13 (a plurality of bipolar electrodes 14, a single negative electrode termination electrode 18, and a single positive electrode termination electrode 19). including. Here, the stacking direction D of the electrode laminated body 11 coincides with the stacking direction of the module laminated body 2. The electrode laminate 11 has a side surface 11b extending in the stacking direction D.

The bipolar electrode 14 includes an electrode plate 15, a positive electrode 16, and a negative electrode 17. The positive electrode 16 is provided on the first surface 15a of the electrode plate 15. The negative electrode 17 is provided on the second surface 15b on the opposite side of the first surface 15a of the electrode plate 15. The electrode plate 15 is made of a metal such as nickel or a nickel-plated steel plate. As an example, the electrode plate 15 is a rectangular metal leaf made of nickel. The electrode plate 15 includes an outer edge 15d having a rectangular shape when viewed from the stacking direction D.

The positive electrode 16 is a positive electrode active material layer formed by applying a positive electrode active material to the electrode plate 15. Examples of the positive electrode active material constituting the positive electrode 16 include nickel hydroxide. The positive electrode 16 includes an outer edge 16d having a rectangular shape when viewed from the stacking direction D. The negative electrode 17 is a negative electrode active material layer formed by applying a negative electrode active material to the electrode plate 15. Examples of the negative electrode active material constituting the negative electrode 17 include a hydrogen storage alloy. The negative electrode 17 includes an outer edge 17d having a rectangular shape when viewed from the stacking direction D.

In the present embodiment, for example, the formation region of the negative electrode 17 on the second surface 15b of the electrode plate 15 is larger than the formation region of the positive electrode 16 on the first surface 15a of the electrode plate 15. That is, the outer edge 17d of the negative electrode 17 is one size larger than the outer edge 16d of the positive electrode 16. The peripheral edge portion 15c of the electrode plate 15 has a rectangular frame shape, and is an uncoated region in which the positive electrode active material and the negative electrode active material are not coated. That is, the peripheral edge portion 15c of the electrode plate 15 is a portion of the electrode plate 15 other than the region where the positive electrode 16 and the negative electrode 17 are formed when viewed from the stacking direction D, and is a portion surrounding the positive electrode 16 and the negative electrode 17. .. The surfaces of the bipolar electrode 14, the negative electrode termination electrode 18, and the positive electrode termination electrode 19 include the first surface 15a and the second surface 15b of the peripheral edge portion 15c of the electrode plate 15, respectively.

In the electrode laminate 11, the positive electrode 16 of one bipolar electrode 14 faces the negative electrode 17 of another bipolar electrode 14 adjacent to each other in the stacking direction D with the separator 13 interposed therebetween. In the electrode laminate 11, the negative electrode 17 of one bipolar electrode 14 faces the positive electrode 16 of yet another bipolar electrode 14 adjacent to the stacking direction D with the separator 13 interposed therebetween.

The negative electrode terminal electrode 18 includes an electrode plate 15 and a negative electrode 17 provided on the second surface 15b of the electrode plate 15. The negative electrode termination electrode 18 does not include the positive electrode 16. That is, the active material layer is not provided on the first surface 15a of the electrode plate 15 of the negative electrode terminal electrode 18 (that is, the entire first surface 15a of the negative electrode terminal 18 is exposed). The negative electrode terminal electrode 18 is arranged at one end of the stacking direction D so that the second surface 15b faces the inside of the stacking direction D of the electrode laminated body 11 (center side with respect to the stacking direction D). The negative electrode 17 of the negative electrode terminal electrode 18 faces the positive electrode 16 of the bipolar electrode 14 at one end in the stacking direction D via the separator 13.

The positive electrode terminal electrode 19 includes an electrode plate 15 and a positive electrode 16 provided on the first surface 15a of the electrode plate 15. The positive electrode termination electrode 19 does not include the negative electrode 17. That is, the active material layer is not provided on the second surface 15b of the electrode plate 15 of the positive electrode terminal electrode 19 (that is, the entire second surface 15b of the positive electrode terminal 19 is exposed). The positive electrode terminal electrode 19 is arranged at the other end of the stacking direction D so that the first surface 15a faces the inside of the stacking direction D of the electrode laminated body 11. The positive electrode 16 of the positive electrode terminal electrode 19 faces the negative electrode 17 of the bipolar electrode 14 at the other end in the stacking direction D via the separator 13.

The conductive plate 5 is in contact with the first surface 15a of the electrode plate 15 of the negative electrode terminal electrode 18. Further, the conductive plate 5 of the adjacent power storage module 4 is in contact with the second surface 15b of the electrode plate 15 of the positive electrode terminal electrode 19. The restraint load from the restraint member 3 is applied to the electrode laminate 11 from the negative electrode terminal electrode 18 and the positive electrode terminal electrode 19 via the conductive plate 5. That is, the conductive plate 5 is also a restraining member that applies a restraining load to the electrode laminated body 11 along the stacking direction D.

The separator 13 is formed, for example, in the form of a sheet. Examples of the separator 13 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric made of polypropylene, methyl cellulose and the like, or a non-woven fabric. The separator 13 may be reinforced with a vinylidene fluoride resin compound. The separator 13 is not limited to a sheet shape, and a bag shape may be used.

The bipolar electrode 14 is provided with an intermediate resin portion 23. The intermediate resin portion 23 functions as a primary seal that seals between the bipolar electrodes 14 and 14. The intermediate resin portion 23 is provided along the outer edge of the bipolar electrode 14, and is provided over the entire circumference of the bipolar electrode 14. The intermediate resin portion 23 is provided by being joined to the outer edge of the electrode plate 15. The end portion of the intermediate resin portion 23 is joined to the sealing body 12. That is, the bipolar electrode 14 is bonded to the sealing body 12 via the intermediate resin portion 23 and is supported by the sealing body 12. The intermediate resin portion 23 includes, for example, a first intermediate resin portion 231 and a second intermediate resin portion 232. The intermediate resin portion 23 may be composed of a single member.

The bipolar electrode 14 is provided with a negative electrode terminal resin portion 24. The negative electrode terminal resin portion 24 is a member provided at the end of the electrode laminate 11 in the stacking direction D, and functions as a primary seal for sealing the end of the electrode laminate 11. The negative electrode terminal resin portion 24 is formed in a rectangular frame shape, for example, and is welded to the surface of the negative electrode terminal electrode 18. The negative electrode terminal electrode 18 is an electrode arranged at the end of the electrode laminate 11, and is composed of an electrode plate 15 and a negative electrode 17.

The bipolar electrode 14 is provided with a positive electrode terminal resin portion 26. The positive electrode terminal resin portion 26 is a member provided at the end of the electrode laminate 11 in the stacking direction D, and functions as a primary seal for sealing the end of the electrode laminate 11. The positive electrode terminal resin portion 26 is formed in a rectangular frame shape, for example, and is welded to the surface of the positive electrode terminal electrode 19. The positive electrode terminal electrode 19 is an electrode arranged at the end of the electrode laminate 11, and is composed of an electrode plate 15 and a positive electrode 16.

The sealing body 12 is provided along the outer edge of the electrode laminated body 11. The sealing body 12 is formed in a rectangular frame shape, and functions as a secondary seal for sealing the side surface 11b of the electrode laminated body 11. The sealing body 12 includes a main body portion 12a and an overhang portion 12b, and is formed of, for example, an insulating resin. The main body portion 12a is formed so as to cover the side surface 11b of the electrode laminated body 11. For example, the main body portion 12a covers the side surface 11b over the entire circumference of the electrode laminated body 11. The overhang portion 12b bends and extends inward of the electrode laminate 11 at the end portion of the main body portion 12a. The overhang portions 12b are formed at both ends of the main body portion 12a, respectively, and suppress the spread of the electrode laminate 11 in the stacking direction D. Here, the inside of the electrode laminate 11 means the center side of the power storage module 4 when viewed from the stacking direction D. On the other hand, the outside of the electrode laminate 11 means a side away from the center of the power storage module 4 when viewed from the stacking direction D.

A reinforcing portion 12c is provided so as to project from the surface of the overhang portion 12b. The reinforcing portion 12c is a reinforcing rib that suppresses deformation of the overhang portion 12b. For example, the reinforcing portion 12c is provided on the surface of the overhang portion 12b opposite to the surface facing the electrode laminated body 11, and projects in the stacking direction D. The reinforcing portion 12c extends from the proximal end side of the overhanging portion 12b toward the distal end side. That is, the reinforcing portion 12c increases the bending rigidity of the overhang portion 12b in the direction from the proximal end side to the distal end side. The reinforcing portion 12c may extend from the position of the base end of the overhang portion 12b to the position of the tip end. Further, the reinforcing portion 12c may extend from a position near the base end of the overhang portion 12b to a position near the tip end.

The sealing body 12 is provided between the bipolar electrodes 14 adjacent to each other along the stacking direction D, between the negative electrode termination electrodes 18 and the bipolar electrodes 14 adjacent to each other along the stacking direction D, and along the stacking direction D. The positive electrode terminal 19 and the bipolar electrode 14 adjacent to each other are sealed from each other. As a result, the internal space V is airtightly (liquid-tight) between the bipolar electrode 14, the negative electrode terminal 18 and the bipolar electrode 14, and the positive electrode terminal 19 and the bipolar electrode 14. Is formed. An electrolytic solution (not shown) composed of an alkaline aqueous solution such as an aqueous solution of potassium hydroxide is housed in this internal space V. That is, the first resin portion 21 is for forming the internal space V in which the electrolytic solution is accommodated between the electrodes adjacent to each other along the stacking direction D, and for sealing the internal space V. The electrolytic solution is impregnated in the separator 13, the positive electrode 16 and the negative electrode 17.

The sealant 12 is, for example, an insulating resin and may be composed of polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), or the like.

FIG. 3 is a plan view of the power storage module 4 when viewed from the stacking direction D. As shown in FIG. 3, the power storage module 4 is configured by providing a sealing body 12 on the outer edge of the rectangular electrode laminated body 11. The electrode laminate 11 is provided by laminating a plurality of electrodes such as a bipolar electrode 14, and has a rectangular cross section in a direction orthogonal to the electrode stacking direction. The sealing body 12 is continuously provided on the outer edge of the electrode laminated body 11 over the entire circumference. That is, the sealing body 12 is continuously provided on the outer edge of the electrode laminated body 11 when the electrode laminated body 11 is viewed from the laminating direction over the entire circumference, and has a rectangular frame shape.

A plurality of reinforcing portions 12c are formed on the overhang portion 12b of the sealing body 12. The reinforcing portion 12c extends from the proximal end side of the overhang portion 12b to the distal end side (from the outside to the inside of the electrode laminate 11). The reinforcing portion 12c is formed so that the width dimension is smaller than the dimension from the outside to the inside of the overhang portion 12b. The reinforcing portion 12c may be formed so that the width dimension is the same as or larger than the dimension from the outside to the inside of the overhang portion 12b. Here, the inside of the overhang portion 12b means the tip end side of the overhang portion 12b and the center side of the power storage module 4 when viewed from the stacking direction D. On the other hand, the outside of the overhang portion 12b is the base end side of the overhang portion 12b, and means the side away from the center of the power storage module 4 when viewed from the stacking direction D.

A plurality of reinforcing portions 12c are formed at predetermined intervals along the forming direction of the side surface 11b of the electrode laminated body 11. For example, a plurality of reinforcing portions 12c may be formed at equal intervals along the forming direction of the side surface 11b of the electrode laminated body 11. In this case, the bending rigidity of the overhang portion 12b is evenly increased. Further, in the reinforcing portion 12c, the reinforcing portion 12c may be formed more or larger as the load received from the electrode laminated body 11 side is larger in the overhang portion 12b. In this case, the bending rigidity of the overhang portion 12b can be increased according to the load received from the electrode laminate 11 side, and the deformation of the overhang portion 12b can be appropriately suppressed. At this time, the reinforcing portions 12c may not be formed at equal intervals along the forming direction of the side surface 11b of the electrode laminated body 11. In FIG. 3, two or three reinforcing portions 12c are formed on one side of the overhang portion 12b, but the reinforcing portions 12c may be formed by a number other than that.

FIG. 4 shows an enlarged cross-sectional view of the reinforcing portion 12c. FIG. 4 shows a cross section of the reinforcing portion 12c in the stacking direction D of the electrode laminated body 11. The reinforcing portion 12c is provided so as to project from the surface of the overhang portion 12b opposite to the surface facing the electrode laminate 11. The protruding length of the reinforcing portion 12c may be set according to the bending strength required for the overhang portion 12b. Further, the protruding length of the reinforcing portion 12c is set to a length that does not come into contact with the reinforcing portion 12c, the overhang portion 12b, etc. of the adjacent power storage modules 4. Further, when the reinforcing portion 12c comes into contact with the overhang portion 12b of the adjacent power storage module 4, a recess is provided in the adjacent overhang portion 12b and the reinforcing portion 12c is inserted into the recess to contact the reinforcing portion 12c. May be avoided.

The reinforcing portion 12c is formed to be shorter than the length of the overhang portion 12b, for example. That is, in the reinforcing portion 12c, the length of the reinforcing portion 12c from the base end side to the tip end side of the overhang portion 12b is shorter than the length of the overhang portion 12b. Here, the overhang portion 12b includes a portion extending inward of the electrode laminate 11 and a portion above the main body portion 12a. That is, the corner portion of the bent sealing body 12 is the base end portion of the overhang portion 12b. Therefore, the length of the overhang portion 12b is the distance from the outer end surface of the sealing body 12 to the tip surface of the overhang portion 12b in FIG. The length of the reinforcing portion 12c may be appropriately set according to the bending strength required for the overhang portion 12b. Further, the reinforcing portion 12c is formed, for example, with a constant protrusion length.

The reinforcing portion 12c is formed so as to straddle the position of the extension line in the stacking direction D on the inner surface of the main body portion 12a, for example. When a load is received from the electrode laminate 11 side, a large bending stress is generated in the overhang portion 12b at a position near the inner surface of the main body portion 12a. At this time, since the reinforcing portion 12c is formed so as to straddle the position of the extension line of the inner surface of the main body portion 12a in the stacking direction D, the bending rigidity of the base end side of the overhang portion 12b is increased, and the overhang portion 12b Deformation can be effectively suppressed.

The reinforcing portion 12c is formed of, for example, a resin. Specifically, at the time of resin molding of the sealing body 12, it may be formed by molding integrally with the sealing body 12.

Next, the deformation suppressing function of the power storage module 4 according to the present embodiment will be described.

In FIG. 2, when the power storage module 4 is used as a battery, the internal pressure of the power storage module 4 may increase. That is, the internal pressure of the electrode laminated body 11 may increase, and a load may be applied to the sealed body 12. In this case, the load in the stacking direction D is applied from the electrode laminated body 11 side to the overhang portion 12b of the sealed body 12.

At this time, it is required that the sealed body 12 receives the load without being deformed as much as possible. Therefore, in the power storage module 4 according to the present embodiment, the reinforcing portion 12c is formed on the overhang portion 12b. That is, as shown in FIG. 5, in the cross section of the electrode laminate 11 in the stacking direction D, the reinforcing portion 12c is formed on the surface of the overhang portion 12b. The reinforcing portion 12c extends from the proximal end side of the overhang portion 12b to the distal end side, and the bending rigidity is increased in the direction from the proximal end side to the distal end side of the overhang portion 12b. Therefore, even when a load (arrow in FIG. 5) is applied to the overhang portion 12b, the deformation of the overhang portion 12b can be accurately suppressed.

As described above, according to the power storage module 4 according to the present embodiment, the bending rigidity of the overhang portion 12b can be increased by forming the reinforcing portion 12c in the overhang portion 12b. Therefore, even if the internal pressure of the electrode laminated body 11 rises and the sealing body 12 is pressed, the deformation of the sealing body 12 can be suppressed. Further, since the bending rigidity of the overhang portion 12b can be increased without increasing the entire overhang portion 12b, the deformation of the sealing body 12 can be suppressed while suppressing the increase in the weight of the sealing body 12.

Further, in the power storage module 4 according to the present embodiment, the reinforcing portion 12c is provided on the surface opposite to the surface of the overhang portion 12b facing the electrode laminate 11, and the overhang portion 12b is provided from the proximal end side to the tip end side. Extends to. Therefore, the bending rigidity of the overhang portion 12b from the base end side to the tip end side is increased, and the deformation of the overhang portion 12b and the sealing body 12 can be appropriately suppressed.

Further, in the power storage module 4 according to the present embodiment, a plurality of reinforcing portions 12c are formed on the surface of the overhang portion 12b along the forming direction of the side surface 11b of the electrode laminate 11 at predetermined intervals, whereby the overhang portion is formed. In 12b, the bending rigidity can be increased in a wide range, and the deformation of the overhang portion can be appropriately suppressed.

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

For example, in the above-described embodiment, the case where the reinforcing portion 12c is formed shorter than the length of the overhang portion 12b has been described as shown in FIG. 5, but as shown in FIG. 6, the reinforcing portion 12c is formed of the overhang portion 12b. It may be formed to have the same length as the length. That is, the length of the reinforcing portion 12c from the base end side to the tip end side of the overhang portion 12b may be the same as the length of the overhang portion 12b. In this case, the reinforcing portion 12c can be formed longer, and the bending rigidity of the overhang portion 12b can be further increased.

Further, in the above-described embodiment, the case where the protruding length of the reinforcing portion 12c is constant has been described as shown in FIG. 5, but the protruding length of the reinforcing portion 12c does not necessarily have to be constant. For example, as shown in FIG. 7, the reinforcing portion 12c may be provided with an inclined surface 12d so that the protruding length of the reinforcing portion 12c on the distal end side is smaller than that on the proximal end side of the overhang portion 12b. In this case, the bending rigidity of the base end side of the overhang portion 12b can be increased. Further, by reducing the protruding length of the reinforcing portion 12c on the tip end side of the overhang portion 12b, it is possible to suppress an increase in weight due to the formation of the reinforcing portion 12c.

Further, in the above-described embodiment, the case where the power storage module 4 is used for the power storage device 1 in which the power storage modules 4 are stacked as shown in FIG. 1 has been described, but the power storage module 4 may be used in a different structure or form. Further, in the above-described embodiment, the case where the power storage module 4 is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles has been described, but it may be used for other purposes.

4 ... Energy storage module, 11 ... Electrode laminated body (laminated body), 12 ... Sealed body, 12a ... Main body part, 12b ... Overhang part, 12c ... Reinforcing part, 12d ... Inclined surface, 14 ... Bipolar electrode, 15 ... Electrode Plate, 15a ... 1st surface, 15b ... 2nd surface, 16 ... positive electrode, 17 ... negative electrode, 18 ... negative electrode terminal electrode, 23 ... intermediate resin part, 24 ... negative electrode terminal resin part, D ... stacking direction.

Claims (3)

In a power storage module having a laminated body in which a plurality of electrodes are laminated and a sealing body provided on the side surface of the laminated body.
The sealing body includes a main body portion that covers the side surface of the laminated body portion, and an overhang portion that bends and extends inward of the laminated body portion at an end portion of the main body portion.
A reinforcing portion that is projected from the surface of the overhang portion in the stacking direction of the laminated body and suppresses deformation of the overhang portion is provided.
The overhang portion includes a portion that overlaps the main body portion in the stacking direction and a portion that extends inward of the laminated body.
The reinforcing portion is provided on the surface of the overhang portion opposite to the surface facing the laminated body, and extends from a portion of the overhang portion overlapping the main body portion to a portion extending inward of the laminated body. A plurality of the overhang portions are formed at predetermined intervals on the surface of the overhang portion along the formation direction of the side surface of the laminated body.
Power storage module. The reinforcing portion is formed with an inclined surface so that the protruding length on the tip side is smaller than that on the base end side of the overhang portion.
The power storage module according to claim 1 . The reinforcing portion is formed to have the same length as the length of the overhang portion.
The power storage module according to claim 1 or 2 .

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