JP2021182465A - Bipolar type power storage device - Google Patents

Abstract

To provide a bipolar type power storage device suppressing occurrence of positional displacement between an insulating plate and a collector member which are adjacently disposed in a restraining plate.SOLUTION: A power storage device 10 comprises: a power storage module 12; a pair of restraining plates 17 and 18 which hold the power storage module 12 therebetween in a lamination direction and add restraining loads to the power storage module 12; a positive electrode collector plate 24 disposed between one restraining plate 18 of the pair of restraining plates 17 and 18 and the power storage module 12 and electrically connected to the power storage module 12; an insulating plate 22 disposed between the restraining plate 18 and the positive electrode collector plate 24; and an adhesive part 23 disposed between the positive electrode collector plate 24 and the insulating plate 22 and connecting the positive electrode collector plate 24 and the insulating plate 22 with each other.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a bipolar power storage device.

A bipolar type secondary battery is known as a battery mounted on a hybrid electric vehicle or an electric vehicle (see Patent Document 1). In this bipolar type secondary battery, a plurality of bipolar type battery laminates are laminated and electrically connected in series, and the current collectors located at both ends in the stacking direction and the electrode tab for taking out the battery output are used. An adhesive portion is arranged between them. In each bipolar battery laminate, a plurality of bipolar electrodes are laminated with an electrolyte layer interposed therebetween. According to this secondary battery, the collector and the electrode tab are fixed by the adhesive portion, so that even when the battery is used in an environment where vibration is applied, the bipolar battery laminate and the electrode tab are separated from each other. The deviation can be suppressed, and the deterioration of the battery performance caused by the deviation can be prevented.

Japanese Unexamined Patent Publication No. 2009-13507

By the way, in a bipolar type power storage device having a plurality of stacked bipolar type power storage modules, in order to improve the energy density or output density of the power storage device, a pair of restraint plates are provided at both ends of the stacked bipolar type power storage modules in the stacking direction. It is considered that a plurality of bipolar energy storage modules are pressurized (constrained) from the stacking direction by the pair of restraining plates. Then, for example, a metal restraint plate is used as the restraint plate in order to apply a stable restraint load to the plurality of bipolar type power storage modules arranged between the pair of restraint plates. When using a metal restraint plate, short-circuit both members between the electrode tabs (current collector members) arranged at both ends of the stacked bipolar power storage modules in the stacking direction and the restraint plate. In order to prevent, for example, an insulating plate made of an insulating resin is arranged. However, the static friction coefficient between the insulating plate made of an insulating resin and the metal current collector member is between two metal plates such as a metal current collector member and a metal current collector arranged in contact with each other. It is smaller than the static friction coefficient. Therefore, when an external force such as vibration is applied to the bipolar type current collector, the position shift between the resin insulating plate and the metal current collector is more likely to occur than the contact portion between the two metal plates. Problems occur.

The present disclosure provides a bipolar power storage device in which the occurrence of misalignment between an insulating plate arranged adjacent to a restraint plate and a current collector member is suppressed.

The bipolar type current collector according to one aspect of the present disclosure includes a power storage module, a pair of restraint plates that sandwich the power storage module in the stacking direction and apply a restraining load to the power storage module, and one of the restraint plates of the pair of restraint plates. A current collector member arranged between the power storage module and electrically connected to the power storage module, an insulating plate arranged between one of the restraint plates and the current collector member, and the current collector. It is provided between the member and the insulating plate, and includes an adhesive portion for connecting the current collecting member and the insulating plate to each other.

According to the above-mentioned power storage device, the adhesive portion that adheres the insulating plate and the current collecting member to each other is unlikely to cause a gap between the insulating plate and the current collecting member.

The insulating plate extends in the longitudinal direction intersecting the laminating direction and in the lateral direction intersecting the laminating direction and the longitudinal direction, and the adhesive portion extends in the longitudinal direction. good. In this case, even when a large external force in the longitudinal direction is applied to the power storage device, the gap between the insulating plate and the current collector member is unlikely to occur.

The insulating plate is an injection-molded product made of resin, and the insulating plate has a first main surface facing the one restraining plate and a second main surface opposite to the first main surface. The insulating plate has a plurality of lightening portions recessed from the first main surface and rib portions erected so as to partition the adjacent lightening portions on the first main surface. You may. In this case, when a restraining load is applied in the stacking direction by the pair of restraining plates, the bonded portion can move into the sink mark. The adhesive portion in the sink mark can maintain the adhesiveness between one of the restraint plates and the insulating plate.

The one restraining plate and at least one of the insulating plates may have a positioning portion for positioning between the one restraining plate and the insulating plate. In this case, the displacement between one of the restraint plates and the insulating plate is unlikely to occur.

At least one of the current collector member and the insulating plate may have a positioning portion for positioning between the current collecting member and the insulating plate. In this case, the gap between the current collector member and the insulating plate is unlikely to occur.

According to the present disclosure, it is possible to provide a bipolar power storage device in which the occurrence of misalignment between an insulating plate arranged adjacent to a restraint plate and a current collector member is suppressed.

FIG. 1 is a schematic perspective view of a bipolar power storage device according to the present embodiment. FIG. 2 is a cross-sectional view of the bipolar power storage device of FIG. FIG. 3 is a top view of the restraint plate. FIG. 4 is a top view of the insulating plate and the adhesive portion. FIG. 5 is a side view of the insulating plate and the adhesive portion. FIG. 6 is a perspective view showing a convex portion provided on the first main surface of the insulating plate. FIG. 7 is a cross-sectional view showing an insulating plate having a convex portion and a restraining plate having a concave portion fitted to the convex portion. FIG. 8 is a top view of the positive electrode current collector plate. FIG. 9 is a cross-sectional view showing a restraint plate, an insulating plate, an adhesive portion, and a positive electrode current collector plate. FIG. 10 is a top view of the insulating plate and the adhesive portion according to the modified example.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are used for the same or equivalent elements, and duplicate description is omitted. The drawings show the XYZ Cartesian coordinate system as needed.

FIG. 1 is a schematic perspective view of a bipolar power storage device according to the present embodiment. FIG. 2 is a cross-sectional view of the bipolar power storage device of FIG. The bipolar type power storage device 10 (hereinafter, simply referred to as a power storage device 10) shown in FIGS. 1 and 2 is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage device 10 includes a plurality of (three in this embodiment) power storage modules 12, but may include a single power storage module 12. The power storage module 12 is between a positive electrode having a positive electrode active material layer formed on the surface of a conductive current collector, a negative electrode having a negative electrode active material layer formed on the surface of the current collector, and a positive electrode and a negative electrode. It is a secondary battery having a power generation element including an electrolyte layer in which an electrolytic solution is held in a separator arranged in the above, and is a bipolar type battery having a plurality of laminated bipolar electrodes. The power storage module 12 is a secondary battery such as a nickel hydrogen secondary battery or a lithium ion secondary battery. In the following description, a bipolar type nickel-metal hydride secondary battery will be illustrated.

The plurality of power storage modules 12 may be laminated with the conductive plate 14 between them. The conductive plate 14 is made of, for example, a metal plate having good conductivity. Hereinafter, when the term "stacking direction" is simply referred to, the "stacking direction" means the stacking direction (Z-axis direction) of the plurality of power storage modules 12. When viewed from the stacking direction, the power storage module 12 and the conductive plate 14 are each formed in a rectangular shape, for example.

In the present embodiment, each power storage module 12 is arranged through an electrode laminate in which a plurality of bipolar electrodes and a plurality of separators holding an electrolytic solution are alternately laminated, and at one end of the electrode laminate in the stacking direction via a separator. It is configured to include a negative electrode terminal electrode and a positive electrode terminal electrode arranged at the other end of the electrode laminate in the stacking direction via a separator. Separators are placed between bipolar electrodes adjacent to each other. Each of the plurality of bipolar electrodes has a current collector, a positive electrode active material layer provided on one surface of the current collector, and a negative electrode active material layer provided on the other surface of the current collector. In other words, each bipolar electrode has a structure in which a positive electrode active material layer, a current collector, and a negative electrode active material layer are laminated and arranged in this order. The pair of bipolar electrodes adjacent to each other in the stacking direction are laminated so that the positive electrode active material layer of one bipolar electrode faces the negative electrode active material layer of the other bipolar electrode with the separator interposed therebetween. In other words, between the pair of bipolar electrodes adjacent to each other in the stacking direction, a positive electrode having a current collector and a positive electrode active material layer, a negative electrode having a current collector and a negative electrode active material layer, and a positive electrode, respectively. A power generation element including an electrolyte layer in which an electrolytic solution is held by a separator arranged between negative electrodes is configured. The stacking direction of the plurality of bipolar electrodes and separators in each power storage module 12 is the same as the stacking direction of the plurality of power storage modules 12 in the power storage device 10. The negative electrode terminal electrode has a current collector and a negative electrode active material layer provided on one surface of the current collector. The negative electrode terminal electrode is arranged so that the surface on which the negative electrode active material layer is formed faces the positive electrode active material layer of the bipolar electrodes adjacent to each other in the stacking direction with the separator interposed therebetween. The positive electrode terminal electrode has a current collector and a positive electrode active material layer provided on one surface of the current collector. The positive electrode terminal electrode is arranged so that the surface on which the positive electrode active material layer is formed faces the negative electrode active material layer of the bipolar electrodes adjacent to each other in the stacking direction with the separator interposed therebetween. A separator and an electrolytic solution are housed in the internal spaces formed between the electrodes adjacent to each other in the stacking direction, and each internal space is sealed by a sealing portion. Exposed portions where the current collector is exposed from the sealing portion are provided on both end faces of the power storage module 12 in the stacking direction. A conductive plate 14 or a current collector plate described later is contact-arranged in this exposed portion, and the power storage module 12 is electrically connected to the conductive plate 14 or the current collector plate.

Of the plurality of stacked power storage modules 12, a positive electrode current collector plate 24 as a current collector is arranged on the outside of the power storage module 12 located at one end in the stacking direction (lower side in the Z direction in FIG. 2). .. The positive electrode current collector plate 24 is composed of, for example, a metal plate having good conductivity, and is electrically connected to the power storage module 12 located at one end. The positive electrode current collector plate 24 has a first main surface 24a and a second main surface 24b on the opposite side of the first main surface 24a. The second main surface 24b faces the power storage module 12 located at one end. The positive electrode current collector plate 24 is formed, for example, in a rectangular shape when viewed from the stacking direction. Of the plurality of stacked power storage modules 12, a negative electrode current collector plate 26 as a current collector is arranged on the outside of the power storage module 12 located at the other end in the stacking direction (upper side in the Z direction in FIG. 2). .. The negative electrode current collector plate 26 is made of, for example, a metal plate having good conductivity, and is electrically connected to the power storage module 12 located at the other end. The negative electrode current collector plate 26 has a first main surface 26a and a second main surface 26b on the opposite side of the first main surface 26a. The second main surface 26b faces the power storage module 12 located at the other end. The negative electrode current collector plate 26 is formed, for example, in a rectangular shape when viewed from the stacking direction. The thickness of each of the positive electrode current collector plate 24 and the negative electrode current collector plate 26 is, for example, 5 mm or less. The conductive plate 14 is electrically connected to the adjacent power storage modules 12. As a result, the plurality of power storage modules 12 are connected in series in the stacking direction. The positive electrode current collector plate 24 is provided with a positive electrode terminal that protrudes in a direction intersecting the stacking direction (for example, in the Y-axis direction). The positive electrode terminal may be integrally molded with the positive electrode current collector plate 24, or may be a terminal member configured as a separate body attached to the positive electrode current collector plate 24. The negative electrode current collector plate 26 is provided with a negative electrode terminal protruding in the same direction as the positive electrode terminal. The negative electrode terminal may be integrally molded with the negative electrode current collector plate 26, or may be a terminal member configured as a separate body attached to the negative electrode current collector plate 26. The power storage device 10 is charged and discharged via these positive electrode terminals and negative electrode terminals.

The conductive plate 14 can also function as a heat sink for releasing the heat generated in the power storage module 12. For example, by providing a plurality of cooling flow paths 14a on the conductive plate 14 and allowing a cooling medium (for example, a gas such as air) to flow through the plurality of cooling flow paths 14a, the power storage module 12 that generates heat is efficiently cooled. can do. Each of the plurality of cooling flow paths 14a is configured as a through hole extending in parallel with each other inside the conductive plate 14, and extends in a direction intersecting the stacking direction (Y-axis direction), for example. Each cooling flow path 14a may extend in the X-axis direction. In the present embodiment, the size of the conductive plate 14 seen from the stacking direction is smaller than that of the power storage module 12, but the size of the conductive plate 14 may be the same size as the power storage module 12 and larger than the power storage module 12. It may be the size.

The power storage device 10 includes a plurality of stacked power storage modules 12, a plurality of conductive plates 14, a positive electrode current collector plate 24, and a restraining member 16 that restrains the negative electrode current collector plate 26 in the stacking direction. The restraint member 16 includes a pair of restraint plates 17, 18 and a plurality of connecting members 19 that connect the restraint plates 17, 18 to each other. The restraint plate 17 and the restraint plate 18 may be connected by a single connecting member 19. The pair of restraint plates 17 and 18 sandwich a plurality of power storage modules 12 in the stacking direction. The restraint plates 17 and 18 apply a restraint load to each power storage module 12 in the stacking direction. The plurality of connecting members 19 are connected to the edges of the restraining plates 17 and 18.

The restraint plate 17 has a first main surface 17a and a second main surface 17b on the opposite side of the first main surface 17a. A plurality of stacked power storage modules 12 are provided on the side of the second main surface 17b of the restraint plate 17. The first main surface 17a of the restraint plate 17 is the outer surface of the power storage device 10. The restraint plate 18 has a first main surface 18a and a second main surface 18b on the opposite side of the first main surface 18a. A plurality of stacked power storage modules 12 are provided on the side of the second main surface 18b of the restraint plate 18. The first main surface 18a of the restraint plate 18 is the outer surface of the power storage device 10. The second main surface 17b of the restraint plate 17 and the second main surface 18b of the restraint plate 18 face each other in the stacking direction. The restraint plate 17 and the restraint plate 18 are formed in a rectangular shape when viewed from the stacking direction. Each of the restraint plates 17 and 18 is made of, for example, iron or iron so that a uniform restraint load can be applied to each portion of the power storage module 12 sandwiched between them in the in-plane direction (X-axis direction in FIG. 2). It is composed of a highly rigid metal material such as aluminum.

The restraint plate 17 is provided with a plurality of through holes H1 that penetrate the restraint plate 17 in the stacking direction. The restraint plate 18 is provided with a plurality of through holes H2 that penetrate the restraint plate 18 in the stacking direction. Each of the plurality of connecting members 19 has a bolt 19a including a shaft portion extending in the stacking direction and a nut 19b screwed into the bolt 19a. The shaft portion of the bolt 19a is inserted into each of the through holes H1 and H2. The head of the bolt 19a is arranged on the first main surface 17a of the restraint plate 17, and the screw tip of the bolt 19a protrudes from the first main surface 18a of the restraint plate 18. A nut 19b is screwed into the screw tip of the bolt 19a. The nut 19b is arranged on the first main surface 18a of the restraint plate 18.

In order to prevent a short circuit between both members, for example, a resin insulating plate 22 having an insulating property is arranged between the restraining plate 17 and the negative electrode current collecting plate 26. In order to prevent a short circuit between both members, for example, a resin insulating plate 22 having an insulating property is arranged between the restraining plate 18 and the positive electrode current collecting plate 24. The insulating plate 22 contains a resin such as polypropylene. The insulating plate 22 is, for example, an injection molded product. The insulating plates 22 arranged adjacent to the restraining plates 17 and 18 are formed, for example, in a rectangular shape when viewed from the stacking direction. The size of the insulating plate 22 is larger than that of the conductive plate 14 when viewed from the stacking direction. The insulating plate 22 has a first main surface 22a facing each of the restraining plates 17 and 18, and a second main surface 22b opposite to the first main surface 22a.

The power storage device 10 includes an adhesive portion 23 that connects the positive electrode current collector plate 24 or the negative electrode current collector plate 26 and the insulating plate 22 to each other. The adhesive portion 23 is arranged between the positive electrode current collector plate 24 or the negative electrode current collector plate 26 and the insulating plate 22. The adhesive portion 23 contains a sealing material or an adhesive such as modified silicone. The thickness of the adhesive portion 23 in the stacking direction is, for example, 1 mm or less. The adhesive portion 23 is arranged between the positive electrode current collector plate 24 or the negative electrode current collector plate 26 and the insulating plate 22. In the present embodiment, since the adhesive portion 23 is not provided so as to cover the entire surface of the insulating plate 22, the second main surface 22b of the insulating plate 22 is the first of the positive electrode current collector plate 24 via the adhesive portion 23. The portion of the main surface 24a or the negative electrode current collector plate 26 facing the first main surface 26a and the first main surface 24a of the positive electrode current collector plate 24 or the first main surface of the negative electrode current collector plate 26 without passing through the adhesive portion 23. It has a portion facing 26a.

The second main surface 17b of the restraint plate 17 is abutted against the negative electrode current collector plate 26 via the insulating plate 22 and the adhesive portion 23, and the second main surface 18b of the restraint plate 18 has the insulating plate 22 and the adhesive portion 23. It is abutted against the positive electrode current collector plate 24 via the positive electrode current collector plate 24. In this state, the restraint plates 17 and 18 are connected to each other by the connecting member 19. As a result, the insulating plate 22, the negative electrode current collector plate 26, the positive electrode current collector plate 24, the conductive plate 14, and the power storage module 12 are sandwiched and unitized, and a restraining load is applied in the stacking direction.

The restraint plate 17 has the same structure as the restraint plate 18, but the restraint plate 18 will be described below as an example. Hereinafter, the restraint plate 18, the insulating plate 22, the adhesive portion 23, and the positive electrode current collector plate 24 will be described in detail with reference to FIGS. 3 to 9.

As shown in FIG. 3, the restraint plate 18 has a plurality of engaging portions 32 that each engage with the plurality of connecting members 19. In this embodiment, a plurality of (for example, five) engaging portions 32 are arranged, for example, at equal intervals along each edge extending in the longitudinal direction (Y-axis direction) of the restraint plate 18. A through hole H2 is provided in each engaging portion 32.

The restraint plate 18 has a plurality of rib portions 38 and a plurality of thin portion 39. In the second main surface 18b of the restraint plate 18, a thin portion 39 formed by removing a wall from the second main surface 18b so as to be recessed is provided in a desired portion, so that the rib portion 38 sandwiched between the thin portions 39 is provided. Is formed. The plurality of rib portions 38 include a plurality of rib portions 38 extending in the X-axis direction, a plurality of rib portions 38 extending in the Y-axis direction, and diagonally intersecting both the X-axis direction and the Y-axis direction. Includes a plurality of extending rib portions 38. Each rib portion 38 extending in the oblique direction connects the two engaging portions 32 to each other. Each of the plurality of thin portions 39 is defined by a plurality of rib portions 38. In the stacking direction, the thickness of each thin portion 39 is thinner than the thickness of each rib portion 38 and the thickness of each engaging portion 32. In the present embodiment, the minimum thickness of each rib portion 38 is 15 mm or more and 25 mm or less. The minimum thickness of each thin portion 39 is 2 mm or more and 7 mm or less. The minimum thickness of each engaging portion 32 is more than 7 mm and 20 mm or less.

The restraint plate 18 may have a plurality of (for example, six) positioning portions 18p for positioning between the restraint plate 18 and the insulating plate 22. In the present embodiment, each positioning portion 18p is a recess having the same depth as the thin portion 39.

As shown in FIG. 4, the insulating plate 22 extends in the longitudinal direction (Y-axis direction) intersecting the stacking direction and in the lateral direction (X-axis direction) intersecting the stacking direction and the longitudinal direction. .. The adhesive portion 23 extends in the longitudinal direction of the insulating plate 22. The insulating plate 22 has an edge portion 22e along the lateral direction at both ends in the longitudinal direction and a central portion 22d arranged between the edge portions 22e in the longitudinal direction. In the longitudinal direction, the length of each edge 22e may be 1/3 or less of the length of the insulating plate 22. The adhesive portion 23 is arranged at the central portion 22d and each edge portion 22e. In the present embodiment, the plurality of adhesive portions 23 are arranged at intervals in the lateral direction of the insulating plate 22. Each adhesive portion 23 extends from one edge portion 22e through the central portion 22d to the other edge portion 22e in the longitudinal direction of the insulating plate 22.

As shown in FIGS. 4 and 5, the insulating plate 22 has a plate-like portion 22s having a first main surface 22a and a second main surface 22b. The second main surface 22b of the plate-shaped portion 22s corresponds to a restraining region for applying a restraining load to the power storage module 12. The ratio of the area where the adhesive portion 23 is provided on the second main surface 22b is determined according to the restraining load, and is, for example, 70% or more.

The insulating plate 22 may have a plurality of (for example, six) positioning portions 22p for positioning between the restraining plate 18 and the insulating plate 22. In the present embodiment, each positioning portion 22p is a protrusion that fits with each positioning portion 18p. Each positioning portion 22p is provided on the first main surface 22a. A plurality of positioning portions 22p are arranged along each edge extending in the longitudinal direction of the rectangular first main surface 22a. When each positioning portion 18p of the restraint plate 18 is a protrusion, each positioning portion 22p may be a recess that fits with each positioning portion 18p.

As shown in FIGS. 6 and 7, each positioning portion 22p is, for example, a crushing rib. Each positioning portion 22p has a first rib 22p1 and a second rib 22p2 arranged apart from each other. When the first rib 22p1 and the second rib 22p2 are press-fitted into the positioning portion 18p which is a recess, as shown in FIG. 7, the first rib 22p1 and the second rib 22p2 are deformed so as to approach each other by being pressed against the positioning portion 18p. As a result, the insulating plate 22 is positioned on the restraining plate 18.

As shown in FIGS. 4 and 5, the insulating plate 22 may have a positioning portion 22q for positioning between the positive electrode current collector plate 24 and the insulating plate 22. In the present embodiment, the insulating plate 22 has a positioning portion 22q at a position corresponding to a corner portion of a restraint region of the insulating plate 22. Each positioning portion 22q is, for example, a protrusion. Each positioning portion 22q is provided on the second main surface 22b of the insulating plate 22. In addition to the positioning portion 22q provided at two corners of the four corners of the rectangular restraint region, another positioning portion 22r may be provided at one of the remaining two corners. good. The positioning portion 22r is, for example, a protrusion.

As shown in FIG. 8, the positive electrode current collector plate 24 may have a positioning portion 24q for positioning between the positive electrode current collector plate 24 and the insulating plate 22. In the present embodiment, the positive electrode current collector plate 24 has a positioning portion 24q at a position corresponding to the positioning portion 22q of the insulating plate 22. Each positioning portion 24q is, for example, a notch or a recess formed so as to fit with the positioning portion 22q. In addition to the positioning portion 24q provided at two corners of the four corners of the rectangular restraint region, another positioning portion 24r may be provided at one of the remaining two corners. good. The positioning portion 24r is, for example, a notch or a recess formed so as to fit with the positioning portion 22r. The positioning portions 24q and 24r may be protrusions, and the positioning portions 22q and 22r may be notches or recesses that fit with the positioning portions 24q and 24r.

As shown in FIG. 9, the insulating plate 22 may have a plurality of rib portions 22u on the first main surface 22a so as to correspond to the rib portions 38 of the restraining plate 18. On the side of the first main surface 22a of the insulating plate 22, a lightening portion is provided in a desired portion so as to be recessed from the first main surface 22a so as to partition the adjacent lightening portion. The provided rib portion 22u is formed. That is, the rib portion 22u is a portion where the insulating plate 22 is thick. By providing the rib portion 22u on the first main surface 22a of the insulating plate 22, a slight sink mark 22v (recess) is generated on the second main surface 22b of the insulating plate 22 at a position corresponding to the rib portion 22u. Since an adhesive portion 23 containing a sealing material or an adhesive is provided between the insulating plate 22 and the positive voltage collector plate 24, the sink mark 22v of the insulating plate 22 is filled with the sealing material or the adhesive. Become.

According to the power storage device 10, the adhesive portion 23 that adheres the insulating plate 22 and the positive electrode current collector plate 24 to each other causes a deviation between the insulating plate 22 and the positive electrode current collector plate 24 (a deviation in a direction intersecting the stacking direction). ) Is unlikely to occur. Similarly, the adhesive portion 23 that adheres the insulating plate 22 and the negative electrode current collector plate 26 to each other is unlikely to cause a gap between the insulating plate 22 and the negative electrode current collector plate 26. Therefore, even when an external force such as vibration is applied to the power storage device 10, the above deviation is unlikely to occur. Therefore, it is possible to suppress interference and short circuit between members due to misalignment. Further, the warp of the positive electrode current collector plate 24 and the negative electrode current collector plate 26 is corrected by the adhesive portion 23.

When the adhesive portion 23 extends in the longitudinal direction of the insulating plate 22, the gap between the insulating plate 22 and the positive electrode current collector plate 24 is displaced even when a large external force in the longitudinal direction is applied to the power storage device 10. And the gap between the insulating plate 22 and the negative electrode current collector plate 26 is unlikely to occur.

When the insulating plate 22 has the rib portion 22u, the adhesive portion 23 can move into the sink mark 22v when a restraining load is applied in the stacking direction by the pair of restraining plates 17 and 18. The adhesive portion 23 in the sink mark 22v can maintain the adhesiveness between the restraining plates 17 and 18 and the insulating plate 22.

When the restraining plate 18 has the positioning portion 18p and the insulating plate 22 has the positioning portion 22p, the displacement between the restraining plate 18 and the insulating plate 22 is unlikely to occur. When the restraining plate 17 has a positioning portion similar to the positioning portion 18p and the insulating plate 22 has the positioning portion 22p, the displacement between the restraining plate 17 and the insulating plate 22 is unlikely to occur. Further, the restraining plates 17 and 18 and the insulating plate 22 can be unitized.

When the insulating plate 22 has the positioning portions 22q and 22r and the positive electrode current collector plate 24 has the positioning portions 24q and 24r, the displacement between the positive electrode current collector plate 24 and the insulating plate 22 is unlikely to occur. When the negative electrode current collector plate 26 has a positioning portion similar to the positioning portions 24q and 24r and the insulating plate 22 has the positioning portions 22q and 22r, the deviation between the negative electrode current collector plate 26 and the insulating plate 22 is unlikely to occur. .. Further, the positive electrode current collector plate 24 or the negative electrode current collector plate 26 and the insulating plate 22 can be unitized.

The power storage device 10 can be manufactured as follows. First, the insulating plate 22 is placed on the second main surface 18b of the restraining plate 18. At this time, the positioning portion 22p of the insulating plate 22 is aligned with the positioning portion 18p of the restraint plate 18. Next, after applying the material of the adhesive portion 23 on the second main surface 22b of the insulating plate 22 using, for example, a dispenser or the like, the positioning portion 24q of the positive electrode current collector plate 24 is aligned with the positioning portion 22q of the insulating plate 22. .. When the positive electrode current collector plate 24 has the positioning unit 24r and the insulating plate 22 has the positioning unit 22r, the positioning unit 24r may be aligned with the positioning unit 22r. For example, first, the positioning portion 24r of the positive electrode current collector plate 24 is aligned with the positioning portion 22r of the insulating plate 22, and then the positive electrode current collector plate 24 is rotated around the positioning portions 22r and 24r to rotate the positive electrode current collector plate 24. The positioning portion 24q is aligned with the positioning portion 22q of the insulating plate 22. Next, the material of the adhesive portion 23 is expanded by pressing the positive electrode current collector plate 24 against the insulating plate 22. As a result, the positive electrode current collector plate 24 and the insulating plate 22 are connected by the adhesive portion 23. Therefore, since the warp of the positive electrode current collector plate 24 is corrected, the positioning accuracy between the positive electrode current collector plate 24 and the insulating plate 22 is improved.

Similarly, the insulating plate 22 is placed on the second main surface 17b of the restraining plate 17, the material of the adhesive portion 23 is applied, and then the negative electrode current collector plate 26 is pressed against the insulating plate 22. As a result, the negative electrode current collector plate 26 and the insulating plate 22 are connected by the adhesive portion 23. Therefore, since the warp of the negative electrode current collector plate 26 is corrected, the positioning accuracy between the negative electrode current collector plate 26 and the insulating plate 22 is improved.

After stacking the power storage module 12 and the conductive plate 14 on the positive electrode current collector plate 24, the negative electrode current collector plate 26 faces downward to the unit including the restraint plate 17, the insulating plate 22, the adhesive portion 23, and the negative electrode current collector plate 26. It is inverted and placed on the power storage module 12. When the unit is inverted, the adhesive portion 23 can suppress the drop of the negative electrode current collector plate 26. After that, the restraint plates 17 and 18 are connected to each other by using a plurality of connecting members 19.

FIG. 10 is a top view of the insulating plate and the adhesive portion according to the modified example. The adhesive portion 123 shown in FIG. 10 has the same configuration as the adhesive portion 23 except that it has a frame shape when viewed from the stacking direction. The adhesive portion 123 has, for example, a rectangular ring shape when viewed from the stacking direction. The adhesive portion 123 extends in the longitudinal direction and the lateral direction of the insulating plate 22. The adhesive portion 123 includes a pair of long side portions 123a extending in the longitudinal direction from one edge portion 22e through the central portion 22d to the other edge portion 22e on the second main surface 22b of the insulating plate 22. It has a pair of short side portions 123b extending in the lateral direction at the edge portion 22e. The adhesive portion 123 does not have to have a pair of long side portions 123a.

Even in the power storage device provided with the adhesive portion 123 shown in FIG. 10, the same operation and effect as the above-mentioned power storage device 10 can be obtained. Further, even when a large external force is applied in an arbitrary direction on the second main surface 22b (XY plane) of the insulating plate 22, the gap between the insulating plate 22 and the positive electrode current collector plate 24 and the insulating plate 22 Misalignment with the negative electrode current collector plate 26 is unlikely to occur.

Although the preferred embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above embodiments.

For example, in the present embodiment, the restraint plate 18 and the insulating plate 22 have the positioning portion 18p and the positioning portion 22p, respectively, but even if only one of the restraining plate 18 and the insulating plate 22 has the positioning portion. good. For example, when the insulating plate 22 does not have the positioning portion 22p, the entire insulating plate 22 may be fitted into the positioning portion (recess) of the restraint plate 18. Further, when the restraint plate 18 does not have the positioning portion 18p, the entire restraint plate 18 may be fitted into the positioning portion 22p (recess) of the insulating plate 22.

Further, in the present embodiment, the insulating plate 22 and the positive electrode current collector plate 24 have the positioning portions 22q, 22r and the positioning portions 24q, 24r, respectively, but only one of the insulating plate 22 and the positive electrode current collector plate 24. May have a positioning unit. Similarly, only one of the insulating plate 22 and the negative electrode current collector plate 26 may have a positioning portion. For example, when the insulating plate 22 does not have the positioning portions 22q and 22r, the entire insulating plate 22 may be fitted into the positioning portion (recess) of the positive electrode current collector plate 24 or the negative electrode current collector plate 26. When the positive electrode current collector plate 24 or the negative electrode current collector plate 26 does not have a positioning portion, the positive electrode current collector plate 24 or the entire negative electrode current collector plate 26 is fitted into the positioning portion (dent) of the insulating plate 22. May be good.

10 ... Bipolar current collector, 12 ... Power storage module, 17, 18 ... Restraint plate, 18p, 22p, 22q, 22r, 24q, 24r ... Positioning unit, 22 ... Insulation plate, 22a ... First main surface, 22b ... Second Main surface, 22u ... Rib portion, 23, 123 ... Adhesive portion, 24 ... Positive electrode current collector plate (current collector member), 26 ... Negative electrode current collector plate (current collector member).

Claims (5)

Power storage module and
A pair of restraint plates that sandwich the power storage module in the stacking direction and apply a restraint load to the power storage module.
A current collector member arranged between one of the pair of restraint plates and the power storage module and electrically connected to the power storage module.
An insulating plate arranged between the one restraint plate and the current collector member,
An adhesive portion arranged between the current collector member and the insulating plate and connecting the current collector member and the insulating plate to each other.
A bipolar type power storage device. The insulating plate extends in the longitudinal direction intersecting the laminating direction and in the lateral direction intersecting the laminating direction and the longitudinal direction.
The bipolar type power storage device according to claim 1, wherein the adhesive portion extends in the longitudinal direction. The insulating plate is an injection molded product made of resin.
The insulating plate has a first main surface facing the one restraining plate and a second main surface opposite to the first main surface.
The insulating plate has, on the first main surface, a plurality of lightening portions recessed from the first main surface, and a rib portion erected so as to partition the adjacent lightening portions. Item 2. The bipolar type power storage device according to Item 1 or 2. The bipolar according to any one of claims 1 to 3, wherein the one restraining plate and at least one of the insulating plates have a positioning portion for positioning between the one restraining plate and the insulating plate. Type power storage device. The bipolar type storage according to any one of claims 1 to 4, wherein at least one of the current collector member and the insulating plate has a positioning portion for positioning between the current collecting member and the insulating plate. Device.

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