Battery pack

Abstract

The problem to be solved by the present invention is to provide a battery pack in which the compressive load generated by pressurization in the stacking direction of a plurality of battery cells can be made uniform, and the safety of batteries can be improved by having few restrictions during mass production. In order to solve the problem, this battery pack (100) is configured by housing a laminated cell (ASSIY) in a housing case (80), and has an end plate (95) on the outer surface of the laminated cell (ASSIY) in the lamination direction of a plurality of battery cells (70), the outer surface of the end plate (95) being in contact with a pressing member (85) for pressing the laminated cell (ASSIY) housed in the housing case (80), and the end plate (95) being in contact with the outer surface of the pressing member (85). The outer surface of the end plate 95 in contact with the pressing member 85 has a convex portion 951 facing the pressing member 85.

Description

Technical Field

[0001] The present invention relates to a battery pack. Background Art

[0002] Conventionally, a battery module formed by stacking a plurality of battery cells has been known (see Patent Document 1).

[0003] [Prior Art Documents]

[0004] (Patent Document)

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-044183 Summary of the Invention

[0006] [Problems to be Solved by the Invention]

[0007] In the above-described battery module, a plurality of battery cells are pressed in the stacking direction of the plurality of battery cells, but the compression load generated by the pressing is uneven. In addition, since the pressing is performed after assembling the stacked cell ASSY formed by stacking a plurality of battery cells, there are restrictions in mass production.

[0008] An object of the present invention is to provide a battery pack that can equalize the compression load generated by pressing in the stacking direction of a plurality of battery cells, has few restrictions in mass production, and improves the safety of the battery.

[0009] [Means for Solving the Problems]

[0010] To achieve the above object, the present invention provides a battery pack including: a stacked cell ASSY formed by stacking a plurality of battery cells (for example, the following "battery cell 70"); and a housing case (for example, the following "case 80") having an open upper portion; and the battery pack (for example, the following "battery pack 100") is formed by housing the stacked cell ASSY in the housing case, and an end plate (for example, the following "end plate 95") is provided on an outer surface of the stacked cell ASSY in the stacking direction of the plurality of battery cells, and an outer surface of the end plate contacts a pressing member (for example, the following "spacer 85"), and the pressing member presses the stacked cell ASSY housed in the housing case, and the outer surface of the end plate in contact with the pressing member has a convex-shaped portion (for example, the following "convex-shaped portion 951") facing the pressing member.

[0011] In the above invention, it is preferred that the stacked cell ASSY is constructed by embedding a plurality of stacked battery cells into a restraining member (for example, the "restraint member 90" described below), and the restraint member is composed of an end side member (for example, the "upper member 92" described below) and another end side member (for example, the "lower member 91" described below). In addition, it is preferred that the aforementioned stacked multiple battery cells are embedded in the aforementioned restraining member in a state where they are pressurized in the stacking direction. In addition, it is preferred that the aforementioned end plate is embedded in the end surface in the stacking direction of the aforementioned multiple battery cells, and the aforementioned multiple battery cells are embedded in the aforementioned restraining member. In addition, it is preferred that the aforementioned end plate is fixed between the frame portion of the aforementioned one end side member and the aforementioned other end side member and the aforementioned battery cell.

[0012] In addition, it is preferred that the convex portion of the end plate protrudes toward the pressurizing member. In addition, it is preferred that a through hole (e.g., the "through hole 801" described below) is formed in the wall portion of the storage case, and the through hole is used for inserting a pressing jig to pressurize the plurality of battery cells through the end plate. In addition, it is preferred that a spacer (e.g., the "spacer 85" described below) is arranged between the end plate of the plurality of battery cells in a pressurized state and the storage case.

[0013] (Effects of the Invention)

[0014] According to the present invention, a battery pack can be provided which can make the compressive load caused by pressurization in the stacking direction of a plurality of battery cells uniform and has fewer restrictions during mass production, thereby improving battery safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a perspective view showing the battery pack in this embodiment.

[0016] Figure 2 It is a plan view showing the battery pack in this embodiment.

[0017] Figure 3 is along Figure 2 Cross-section diagram along line AA.

[0018] Figure 4 It is a plan view of an end portion in the stacking direction of a battery stack of the battery pack in the present embodiment.

[0019] Figure 5 It is an enlarged perspective view of an end portion in the stacking direction of a battery stack of the battery pack in the present embodiment.

[0020] Figure 6 It is a partially enlarged cross-sectional view of an end portion in the stacking direction of a battery stack of the battery pack in the present embodiment.

[0021] Figure 7is an exploded perspective view showing the battery pack in the present embodiment.

[0022] Figure 8 is a perspective view showing the battery module of the battery pack in the present embodiment.

[0023] Figure 9 is a view showing the situation where the upper member and the lower member are inserted into the battery module of the present embodiment from the upper side and the lower side of the battery laminate.

[0024] Figure 10 is a side view showing the battery module of the present embodiment.

[0025] Figure 11 is along Figure 10 sectional perspective view taken along line B-B.

[0026] Figure 12 is along Figure 10 sectional perspective view taken along line C-C.

[0027] Figure 13 is an enlarged perspective view showing the battery module of the present embodiment.

[0028] Figure 14 is a perspective view showing the state of the battery module of the present embodiment before being inserted into the housing.

[0029] Figure 15 is a perspective view showing an assembly jig for inserting a restraint member into the battery laminate of the battery module of the present embodiment.

[0030] Figure 16 is a view for explaining the situation where a restraint member is inserted into the battery laminate of the battery module of the present embodiment in the assembly jig.

[0031] Figure 17 is a side sectional view showing the situation where the lower member of the restraint member is inserted into the battery laminate of the battery module of the present embodiment.

[0032] Figure 18 is along Figure 17 sectional view taken along line D-D.

[0033] Figure 19 is a view for explaining the situation where the lower member and the upper member of the restraint member are inserted into the battery laminate of the battery module of the present embodiment in a pressurized state.

[0034] Figure 20 is a view for explaining the situation where a restraint member is inserted into the battery laminate of the present embodiment.

[0035] Figure 21 is a view for explaining the situation where the battery module of the present embodiment is inserted into the housing.

[0036] Figure 22 This is a view showing the case where the battery module in the present embodiment is inserted into the housing.

[0037] Figure 23 This is a perspective view showing the case where the lower member of the restraint member of the battery module in the present embodiment is inserted into the groove formed on the upper surface of the upper pushing jig.

[0038] Figure 24 This is a perspective view showing the case where the battery laminate is arranged with the lower member of the restraint member of the battery module in the present embodiment inserted into the groove formed on the upper surface of the upper pushing jig.

[0039] Figure 25 This is a perspective view showing the case after the battery laminate is arranged with the lower member of the restraint member of the battery module in the present embodiment inserted into the groove formed on the upper surface of the upper pushing jig.

[0040] Figure 26 This is a perspective view showing the case where the battery laminate arranged on the lower member of the restraint member of the battery module in the present embodiment is pressed in the stacking direction of the battery cells.

[0041] Figure 27 This is a sectional view showing the case where the battery laminate arranged on the lower member of the restraint member of the battery module in the present embodiment is pressed in the stacking direction of the battery cells.

[0042] Figure 28 This is a perspective view showing the case where the lower member is inserted from the lower side and the upper member is inserted from the upper side while the battery laminate arranged on the lower member of the restraint member of the battery module in the present embodiment is in a state of being pressed in the stacking direction of the battery cells.

[0043] Figure 29 This is a sectional view showing the case where the lower member is inserted from the lower side and the upper member is inserted from the upper side while the battery laminate arranged on the lower member of the restraint member of the battery module in the present embodiment is in a state of being pressed in the stacking direction of the battery cells.

[0044] Figure 30 This is a perspective view showing the case where the pressing jig composed of a round bar is retracted from the battery laminate while the lower member and the upper member of the restraint member of the battery module in the present embodiment are inserted into the battery laminate. Detailed Embodiments

[0045] Hereinafter, embodiments of the present invention will be described. As Figure 1As shown in the figure, the battery pack 100 includes a restraint member 90, a housing 80, two battery laminates Bs, a flow path member 60, a single cell restraint plate 30, and a cover 20.

[0046] Hereinafter, as Figure 2 shown in the figure, two specific directions orthogonal to each other in the horizontal plane are referred to as the "X direction" and the "Y direction". In addition, one direction of the X direction is referred to as the "X - direction", and the opposite direction of the X direction is referred to as the "X + direction". In addition, one direction of the Y direction is referred to as the "Y - direction", and the opposite direction of the Y direction is referred to as the "Y + direction".

[0047] As Figure 1 , Figure 2 shown in the figure, the housing 80 has a box - shaped shape that opens upward, and the two battery laminates Bs are accommodated side by side in the X direction. The material of the housing 80 is metal or the like.

[0048] As Figure 6 shown in the figure, on the outer surface of the front wall of the housing 80 (the surface opposite to the battery laminate Bs side), a through - hole 801 is formed as described below. The through - hole 801 is for inserting a pressing jig 505 (refer to Figure 15 the figure) composed of a pressing rod to press the battery laminate Bs through an end plate 95. At a position opposite to the through - hole 801, a spacer 85 as a pressing member is provided. The spacer 85 as a pressing member contacts a relatively thick convex portion of the following end plate 95 and presses the battery laminate Bs.

[0049] At a position of the spacer 85 opposite to the through - hole 801, a disk - shaped concave portion 851 that is recessed toward the battery laminate Bs side is formed. A pressure release valve (not shown) is provided in the through - hole 801.

[0050] As Figure 2 shown in the figure, each battery laminate Bs includes a plurality of battery cells 70 and a plurality of separators 79. Each battery laminate Bs is in a state of being constrained by the restraint member 90 and constitutes a battery module 200. By arranging end plates 95 (refer to Figure 3 the figure) at the ends in the stacking direction of the battery module 200, a stacked cell ASSY is constituted.

[0051] Each battery cell 70 has a rectangular outer package that is elongated in the Y direction. Thus, the "Y direction" can also be referred to as the "cell length direction". In each battery laminate Bs, the battery cells 70 are stacked in the X direction. Thus, the "X direction" can also be referred to as the "stacking direction". The separator 79 is a plate - like member that extends in the Y direction and the up - and - down directions, and is disposed between every two battery cells 70 arranged in the X direction. The material of the separator 79 is resin or the like.

[0052] Between the battery stack Bs on the Y-direction side and the housing 80, between the two battery stacks Bs, and between the battery stack Bs on the Y+ direction side and the housing 80, there are provided plate-shaped spacers 89 extending in the X direction and the up-and-down direction. The material of the spacers 89 is resin or the like.

[0053] Each battery cell 70 has a positive electrode p at one end in the Y direction on the upper surface of the outer package (refer to Figure 2 , Figure 13 etc.), and has a negative electrode n at the other end in the Y direction on the upper surface of the outer package (refer to Figure 13 etc.). Specifically, for a specific plurality of battery cells 70, the positive electrode p is arranged on the Y- direction side, and the negative electrode n is arranged on the Y+ direction side. On the other hand, for the other battery cells 70, the negative electrode n is arranged on the Y- direction side, and the positive electrode p is arranged on the Y+ direction side.

[0054] The electrodes p and n of the battery cells 70 adjacent to each other in the Y direction or the X direction are electrically connected to each other by a conductive member (not shown). On the other hand, the positive electrode p of the battery cell 70 that is electrically the most positive is electrically connected to the positive electrode P of the entire battery pack 100 by a conductive member (not shown). In addition, the negative electrode n of the battery cell 70 that is electrically the most negative is electrically connected to the negative electrode N of the entire battery pack 100 by another conductive member (not shown). By the above, in the present embodiment, all the battery cells 70 in the battery pack 100 are connected in series.

[0055] As Figure 2 shown, each battery cell 70 has a safety valve 76 at the central portion of the upper surface of the outer package, and the safety valve 76 can discharge the gas inside the battery cell 70. Specifically, the portion of the upper surface of the outer package of each battery cell 70 that constitutes the safety valve 76 is configured to be more fragile than other portions. Thus, when the pressure inside the battery cell 70 rises, that is, when the pressure inside the outer package rises, the portion of the outer package that constitutes the safety valve 76 is first damaged, thereby performing pressure reduction.

[0056] The flow path member 60 is a member made of an insulator such as resin, and is provided for each battery stack Bs. Each flow path member 60 is provided on the upper surface of the battery stack Bs corresponding to itself.

[0057] As Figure 2 , Figure 7 etc. shown, the single-cell restraining plate 30 is a long plate-shaped member extending in the X direction, and is arranged in parallel with the X direction at the central position on the upper surface of a pair of battery stacks Bs in the battery pack 100, and at both ends in the Y direction. The single-cell restraining plate 30 absorbs the height deviation of the battery cells 70 by clamping and restraining the deviation of the following upper member 92 of the restraining member 90 together with the cover 20 from above.

[0058] The material of the single unit suppression plate 30 is metal or the like. In the portion of the single unit suppression plate 30 located above the flow path member 60, a flow path forming portion (not shown) for the refrigerant to flow through is formed. As Figure 7 shown, the cover 20 is formed in a rectangular plate shape and covers the single unit suppression plate 30 from above. The material of the cover 20 is metal or the like. The cover 20 constitutes a water jacket for allowing the refrigerant to flow in the flow path member 60.

[0059] The stacked single unit ASSY is configured such that end plates 95 are disposed at the ends in the stacking direction (the horizontal lateral direction) of the battery module 200, and includes a battery stack Bs, a restraint member 90, and end plates 95. As Figure 9 shown, the restraint member 90 has a lower member 91 and an upper member 92, and by means of the restraint member 90, the state in which the battery cells 70 in the battery stack Bs are pressurized is maintained. The lower member 91 has: a rectangular lower frame portion 911 having an opening portion 913 with a central opening; and side wall portions 912 that stand up from a pair of long sides of the lower frame portion 911 upward; and restrains a plurality of battery cells 70 from the lower side of the battery stack Bs.

[0060] As Figure 9 , Figure 10 , Figure 12 shown, the lower frame portion 911 constitutes a seamless annular frame that surrounds the periphery of the lower end portion of the battery stack Bs. With this configuration, the lower frame portion 911 is embedded and disposed so as to surround the periphery of the lower end portion of the battery stack Bs, whereby the lower frame portion 911 restrains the lower end portion of the battery stack Bs in the stacking direction of the plurality of battery cells 70 in the battery stack Bs.

[0061] The side wall portions 912 face and cover from the lower end portion to the vicinity of the upper end portion of the side surface portion of the battery stack Bs. As Figure 14 shown, at the upper end portion of the side wall portions 912, a plurality of trapezoidal protrusion portions 916 protrude upward from the upper end edge of the side wall portions 912 and are located at positions protruding more upward than the upper surface of the upper member 92. As Figure 13 shown, the upper member 92 and the lower member 91 are joined by embedding or adhesion at the side surface portion of the outer peripheral portion of the battery stack Bs. By joining the upper member 92 and the lower member 91, the restraint member 90 has a shape in which the upper surface and the lower surface are entirely open, and the end surfaces at both ends in the stacking direction of the battery stack Bs are open. In addition, for the sake of convenience in explanation, in Figure 14 the figures other than, the protrusion portions 916 are omitted.

[0062] On the outer surface of the side wall portion 912, a plurality of trapezoidal convex portions 915 protrude in a direction away from the outer surface of the side wall portion 912. The convex portion 915 is configured to be appropriately flattened by being squeezed from the side by the side wall portion 912 of the lower member 91 toward the inside of the battery laminate Bs. Thereby, it is configured to absorb the length deviation in the monomer length direction of the battery cell 70.

[0063] The upper member 92 has a rectangular upper frame portion 921 and restrains a plurality of battery cells 70 from above the battery laminate Bs. The rectangular upper frame portion 921 has an opening portion 923 with a central opening. As Figure 9 、 Figure 11 and so on show, the upper frame portion 921 forms a seamless annular frame surrounding the periphery of the upper end portion of the battery laminate Bs. With this configuration, the upper frame portion 921 is embedded and arranged so as to surround the periphery of the upper end portion of the battery laminate Bs. Thus, the upper frame portion 921 restrains the upper end portion of the battery laminate Bs in the stacking direction of the plurality of battery cells 70 in the battery laminate Bs.

[0064] As Figure 13 shows, on the upper surface of the long side of the upper member 92, a plurality of trapezoidal convex portions 925 protrude upward. The convex portion 925 is configured to be appropriately flattened by being squeezed from above by the cell suppression plate 30 and the lid 20 toward the lower side. Thereby, the height deviation of the battery cell 70 is absorbed.

[0065] The end plate 95 is inserted into the front surface in the stacking direction of the plurality of battery cells 70, that is, the end surface of the battery laminate Bs in the same direction. The plurality of battery cells 70 are inserted into the restraining member 90. Specifically, the end plate 95 is formed in a rectangular plate shape made of resin and is fixed between the lower frame portion 911 and the upper frame portion 921 (refer to Figure 9 etc.) of the upper member 92 and the lower member 91 and the battery laminate Bs, and is fixed between the front wall of the housing 80 (refer to Figure 3 、 Figure 6 etc.) and the battery laminate Bs.

[0066] The peripheral portion of the end plate 95 is formed to be thinner. Therefore, as Figure 3 shows, the portion other than the peripheral portion has a convex-shaped portion 951 that is relatively thicker than the peripheral portion. As Figure 3 and so on show, the relatively thick convex-shaped portion 951 protrudes in the stacking direction from the openings at the end faces of both ends of the restraining member 90 in the stacking direction of the battery laminate Bs. Thus, the convex-shaped portion 951 protrudes from the restraining member 90 toward the spacer 85 that is a pressing member for pressing the battery laminate Bs.

[0067] Next, the assembly method of the battery pack 100 configured as described above will be described. First, an overview (image) of the assembly method of the battery pack 100 will be described.

[0068] In the assembly method of the battery pack 100, first, as Figure 8 shown, while the battery stack Bs is being pressed in the stacking direction of the battery cells 70 in the battery stack Bs, the battery module 200 in a state of being constrained by the constraining member 90 is assembled. That is, as Figure 19 shown, the upper member 92 and the lower member 91 constituting the constraining member 90 are inserted into the battery stack Bs in a pressed state in the stacking direction of the battery cells 70. As Figure 20 shown, for the upper member 92, it is inserted from the upper side, and for the lower member 91, it is inserted from the lower side. Next, as Figure 21 shown, the protrusion 916 of the lower member 91 is grasped and suspended by the grasping jig 507 and inserted into the housing 80. As Figure 22 shown, it is stuffed into the housing 80 from the upper side.

[0069] The specific assembly method of the battery pack 100 is as follows. In the assembly method of the battery pack 100, the assembly jig 500 shown in Figure 15 is used. The assembly jig 500 includes: a chassis 501, an abutment wall 502 or a round bar 502A constituting a pressing jig as a pressing device (refer to Figure 19 , Figures 26 - 30 ), an upward pushing jig 503, an upward pushing pin 504, and a pressing jig 505 constituted by a round bar as a pressing device.

[0070] In the assembly method of the battery pack 100, first, as Figure 23 shown, the lower frame portion 911 of the lower member 91 is set in the groove 5031 formed on the upper surface of the upward pushing jig 503. Next, as Figure 24 shown, the battery stack Bs is inserted into the lower member 91 from the upper side of the lower member 91. As Figure 25 shown, the battery stack Bs is arranged at a position where it can be inserted into the lower member 91.

[0071] Next, as Figure 26 , Figure 27 shown, the battery stack Bs is pressed from both sides in the stacking direction in such a manner that it is clamped by the pressing jig 505 and the round bar 502A in the stacking direction of the battery cells 70 in the battery stack Bs. The pressing pressure at this time is 0.5 KN or more and 1.5 KN or less. This is because when the pressure is less than 0.5 KN, sufficient compression cannot be achieved, and once it exceeds 1.5 KN, the battery cells 70 constituting the battery stack Bs will be damaged. In addition, when using the abutment wall 502 constituting the pressing jig (refer to Figures 15 - 18) is used to replace the round bar 502A that constitutes the pressing jig (refer to Figure 19 , Figures 26 - 30 ), the battery stack Bs is pressed from the side of the pressing jig 505.

[0072] Next, as shown in Figure 28 , Figure 29 , when the battery stack Bs is compressed to a specific distance by pressing, the lower member 91 is inserted in a manner that covers the plurality of battery cells 70 stacked in the horizontal direction as the lateral direction from below. Specifically, as shown in Figure 17 , Figure 18 , by raising the upward pushing jig 503 and the upward pushing pin 504, the lower member 91 is pushed upward to raise the lower member 91, so that the lower member 91 is inserted into the battery stack Bs from below.

[0073] Next, as shown in Figure 28 , the upper member 92 that covers the upper surface of the battery cells 70 is inserted from above the plurality of battery cells 70 stacked in the horizontal direction as the lateral direction and being pressed. Specifically, as shown in Figure 28 , Figure 29 , the upper member 92 is inserted from above the battery stack Bs in a manner that surrounds the peripheral portion of the upper part of the battery stack Bs for one week from above the pressed battery stack Bs.

[0074] Moreover, the upper member 92 and the lower member 91 inserted above and below the battery stack Bs are joined at the side surfaces of the outer peripheral portion of the battery stack Bs by insertion or adhesion. And, as shown in Figure 30 , the pressing jig 505 and the round bar 502A that are pressed in a manner of clamping the battery stack Bs are separated from each other. The above processes are the processes until the assembly of the battery module 200 is completed in the assembly method of the battery pack 100. In addition, on the outer surface of the end portion in the stacking direction of the battery stack Bs, the end plate 95 is arranged in a state where its thicker portion protrudes from the restraint member 90. After that, the battery module 200 is inserted into the housing 80, and the assembly of the battery pack 100 is completed.

[0075] The effects of using the above-described embodiment are as follows.

[0076] In this embodiment, the restraint member 90 of the battery module 200 that constitutes the battery pack 100 is composed of the upper member 92 and the lower member 91. The upper member 92 is a frame member for restraining from the upper side of the plurality of battery cells 70 stacked in the lateral direction, and the lower member 91 is a frame member for restraining from the lower side of the plurality of battery cells 70 stacked in the lateral direction. The restraint member 90 restrains the plurality of battery cells 70 stacked in the stacking direction.

[0077] Accordingly, it is possible to perform fixation in a state where a plurality of battery cells 70 are compressed and constrained by a constraint member 90 serving as a frame. Therefore, it is possible to reduce the occupied volume of accessory parts other than the battery cells 70 in the Intelligent Power Unit (IPU), thereby improving the cell filling rate and extending the cruising range of a Battery Electric Vehicle (BEV). In particular, the upper member 92 and the lower member 91 are formed of a seamless frame embedded in a plurality of stacked battery cells 70, whereby reliable constraint can be achieved using the constraint member 90.

[0078] In addition, in the present embodiment, the upper member 92 and the lower member 91 of the battery module 200 are joined by embedding or adhesion at the side surfaces of the outer peripheral portions of the plurality of stacked battery cells 70. Accordingly, the lower member 91 can be configured to be located more outside than the upper member 92 and joined to the upper member 92. Therefore, it can be used for purposes other than constraining the lower member 91 as the constraint member 90. For example, in a configuration where the upper end portion of the lower member 91 has a protrusion 916, the battery module 200 can be carried by grasping the protrusion 916. In addition, it is possible to reduce the number of parts by the vertically integrated structure of the constraint member 90, thereby achieving cost reduction.

[0079] In the present embodiment, the upper member 92 is configured to cover the upper end portions of the plurality of battery cells 70 stacked in the lateral direction and is open with respect to the upper surfaces of the plurality of battery cells 70 stacked in the lateral direction. In addition, the lower member 91 is configured to cover the lower end portions of the plurality of battery cells stacked in the lateral direction and is open with respect to the lower surfaces of the plurality of battery cells stacked in the lateral direction. In addition, the end portions of the constraint member 90 that constrains the plurality of stacked battery cells 70 are open in the stacking direction.

[0080] Accordingly, it is possible to form a frame structure that covers the upper and lower end portions of the entire battery stack Bs having the battery cells 70 and, when the reaction force decreases due to compression of the battery cells 70, it is possible to suppress movement of the constraint member 90 relative to the battery cells 70 of the battery stack Bs.

[0081] In the present embodiment, the method for assembling the battery module 200 includes the following steps: arranging a plurality of battery cells 70 in a stacked state on an assembly jig 500; pressing the arranged plurality of battery cells 70 in the stacking direction by a pressing jig 505 as a pressing device; when the plurality of battery cells 70 are compressed to a specific distance by pressing, inserting a lower member 91 so as to cover the plurality of battery cells 70 stacked in the horizontal direction as the lateral direction from below; inserting an upper member 92 covering the upper surface of the battery cells 70 from the upper surface of the plurality of battery cells 70 stacked in the lateral direction that have been pressed; and joining the upper member 92 and the lower member 91 inserted above and below the battery cells 70.

[0082] More specifically, for example, the lower side portion of the assembly jig 500 has an upper pushing jig 503 including an upper pusher 504 as a pusher and a groove 5031 as a groove portion. In the step of inserting the lower member 91, the lower member 91 is arranged in the groove 5031, and the lower member 91 is pushed upward by the upper pushing jig 503 including the upper pusher 504, so that the plurality of stacked battery cells 70 are inserted into the lower member 91. Thereby, the battery stack Bs as the stacked battery cells 70 can be fixed to the restraint member 90 without being lifted. Therefore, a battery module 200 with good mountability can be manufactured.

[0083] In addition, in the present embodiment, in the step of pressing the battery cells 70, the plurality of stacked battery cells 70 are fixed to the assembly jig 500 and pressed and compressed with a pressure of 0.5 KN or more and 1.5 KN or less by the pressing jig 505. Thereby, the overall length of the battery stack Bs composed of the plurality of stacked battery cells 70 can be appropriately compressed to a specific distance (specific length).

[0084] In addition, in the present embodiment, in the step of pressing the battery stack Bs, the plurality of stacked battery cells 70 are pressed from one side or both sides in the stacking direction. Thereby, the battery stack Bs can be appropriately pressed from one side or both sides.

[0085] In addition, in the present embodiment, in the step of inserting the lower member 91, the lower member 91 is raised from the lower side portion of the assembly jig 500 and inserted from below the plurality of stacked battery cells 70. More specifically, in the step of inserting the lower member 91, the lower member 91 is raised by the pusher 504 of the assembly jig 500. Thereby, a configuration can be provided in which the lower member 91 is raised without lowering the battery stack Bs, and thus the configuration of the assembly jig 500 can be prevented from becoming complicated.

[0086] In addition, in the present embodiment, in the process of embedding the upper member 92, the upper member 92 is embedded from the upper side of the stacked plurality of battery cells 70 in which the lower member 91 is embedded on the lower side. Thereby, it is possible to suppress the configuration of the assembly jig 500 from becoming complicated, and the assembly jig 500 can embed the upper member 92 from the upper side without raising the battery stack Bs.

[0087] In addition, in the present embodiment, in the process of joining the upper member 92 and the lower member 91, the upper member 92 and the lower member 91 are joined by fitting or welding. Thereby, it is possible to reduce the number of parts by the upper and lower integral structure of the constraint member 90, and thus it is possible to achieve cost reduction.

[0088] In addition, in the present embodiment, in the battery pack 100, on the outer surface of the stacked monomer ASSY in the stacking direction of the plurality of battery cells 70, there is an end plate 95, and the outer surface of the end plate 95 contacts the pressing jig 505 which is a pressing device for pressing the stacked monomer ASSY. The outer surface of the end plate 95 in contact with the pressing jig 505 has a convex-shaped portion 951 which is a convex-shaped portion facing the pressing jig 505.

[0089] Thereby, by pushing the convex-shaped portion 951, a compressive load generated by pressing is applied to the entire surface of the end plate 95 on the side opposite to the convex-shaped portion 951 side in the stacking direction of the battery cells 70 of the battery stack Bs. Therefore, by pressing integrally with the end plate 95, it is possible to uniformly press the stacked monomer ASSY. In addition, by pressing the convex-shaped portion 951 of the end plate 95, when uniformly pressing the stacked monomer ASSY, a limited range in the center of the battery cell 70 is pressed, and as described above, it is possible to uniformly press the stacked monomer ASSY. In addition, since it is possible to press the convex-shaped portion 951 before embedding in the housing 80, thereby compressing the plurality of battery cells 70, it is possible to reduce the constraints during mass production.

[0090] In addition, in the present embodiment, the end plate 95 is embedded in the end surface in the stacking direction of the plurality of battery cells 70, and the plurality of battery cells 70 are embedded in the constraint member 90. And the end plate 95 is fixed between the upper frame portion 921 and the lower frame portion 911 which are the frame portions of the upper member 92 and the lower member 91 and the battery cell 70. And the portion 951 which is the convex-shaped portion of the end plate 95 protrudes toward the pressing jig 505 which is a pressing member with respect to the constraint member 90.

[0091] Thereby, by pressing the portion 951 which is the convex-shaped portion toward the battery cell 70, it is possible to uniformly press the battery cells 70 of the battery stack Bs on the entire surface on the side of the end plate 95 opposite to the portion 951 which is the convex-shaped portion.

[0092] In addition, the present invention is not limited to the above-described embodiments, and modifications, improvements, etc. within the scope capable of achieving the object of the present invention are included in the present invention.

[0093] For example, the restraining member may also be configured to have a member in which one end side and the other end side are paired in a direction other than the vertical direction, for example, the left-right direction, instead of the lower member 91 and the upper member 92.

[0094] In addition, in the process of inserting the upper member 92, the upper member 92 may be inserted from the upper side of the plurality of stacked battery cells before inserting the lower member 91 from the lower side, instead of inserting the upper member 92 from the upper side of the plurality of stacked battery cells after inserting the lower member 91 from the lower side.

[0095] Reference numerals

[0096] 70 Battery cell

[0097] 80 Housing (accommodating housing)

[0098] 85 Spacer

[0099] 90 Restraining member (monomer ASSY housing)

[0100] 91 Lower member (other end side member)

[0101] 92 Upper member (one end side member)

[0102] 95 End plate

[0103] 100 Battery pack

[0104] 200 Battery module

[0105] 500 Assembly jig

[0106] 504 Upper push pin

[0107] 505 Pressing jig (pressing device)

[0108] 801 Through hole

[0109] 913, 923 Opening

[0110] 916 Protrusion (grasped portion)

[0111] 951 Convex-shaped portion (convex-shaped part)

Claims

1. A battery pack, comprising: A stacked cell ASSY is composed of multiple stacked battery cells; and, The storage shell is in the shape of a box with an opening at the top; and, The battery pack is formed by accommodating the stacked unit ASSY in the accommodating case. The outer surface of the stacked unit ASSY in the stacking direction of the plurality of battery units has an end plate. The outer surface of the end plate contacts a pressurizing member, and the pressurizing member pressurizes the stacked unit ASSY housed in the housing case. The outer surface of the end plate in contact with the pressurizing member has a convex portion facing the pressurizing member.

2. The battery pack according to claim 1, wherein: The stacked cell ASSY is formed by fitting a plurality of stacked battery cells into a restraining member, and the restraining member is composed of a one end side member and a other end side member.

3. The battery pack according to claim 2, wherein: The stacked plurality of battery cells are inserted into the restraining member in a state where they are pressurized in the stacking direction.

4. The battery pack according to claim 2, wherein: The end plate is embedded in the end surface of the plurality of battery cells in the stacking direction, and the plurality of battery cells are embedded in the restraining member.

5. The battery pack according to claim 2, wherein: The end plate is fixed between the frame portions of the one end side member and the other end side member and the battery cell.

6. The battery pack according to claim 2, wherein: The convex portion of the end plate protrudes toward the pressing member.

7. The battery pack according to claim 1, wherein: A through hole is formed in the wall portion of the storage case, and the through hole is used for inserting a pressing jig to pressurize the plurality of battery cells via the end plate.

8. The battery pack according to claim 1, wherein: A spacer is disposed between the end plates of the plurality of battery cells in a pressurized state and the storage case.

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