JP2018026244A - Battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module capable of suppressing a stacked body of battery cells from being deflected.SOLUTION: A battery module 1 includes: a stacked body 10 including a plurality of battery cells 12 stacked one another along a first direction; a pair of restraint fixing mechanisms 20 applying a restraint load to the stacked body 10 along the first direction and fixing the stacked body 10 to a member M to be fixed at both end sides of the stacked body 10 in the first direction; and a fixing member 40 disposed between the pair of restraint fixing mechanisms 20 and fixing the stacked body 10 to the member M to be fixed. The restraint fixing mechanisms 20 fix the stacked body 10 to the member M to be fixed such that the battery cells 12 can slide along the first direction while resisting the restraint load.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery module.

  Patent Document 1 describes an assembled battery (battery module) formed by integrally stacking a plurality of prismatic battery cells. In this assembled battery, a metal restraint plate is abutted against a prismatic battery cell located at an end of the stacked prismatic battery cells. The pair of restraining plates are connected to each other by a long connecting member so that the square battery cell is pressed.

JP 2001-236937 A

  When fixing the above-described battery module to the battery pack casing, for example, predetermined fixing members are installed at both ends of the battery module in the stacking direction of the battery cells, and the battery module is attached to the casing at both ends of the battery module. It is assumed to be fixed. In this case, when vibration or impact is applied to the battery module, the battery cell stack may be bent in a direction intersecting the stacking direction. Further, expansion of the battery cell due to deterioration of the battery cell or the like may cause the stack to bend.

  An object of this invention is to provide the battery module which can suppress the bending of the laminated body of a battery cell.

  A battery module according to the present invention includes a stacked body including a plurality of battery cells stacked together along a first direction, and a stack in the first direction while applying a restraining load to the stacked body along the first direction. A pair of restraining and fixing mechanisms for fixing the laminate to the fixed member on both ends thereof, and a fixing member disposed between the pair of restraining and fixing mechanisms and fixing the laminate to the fixed member. The restraint fixing mechanism fixes the stacked body to the member to be fixed so that the battery cell can slide along the first direction while resisting the restraint load.

  In this battery module, the restraint fixing mechanism applies a restraint load to the stacked body including a plurality of battery cells stacked together in the first direction (stacking direction), and the battery cells resist the restraint load. However, the laminate is fixed to the member to be fixed at both ends of the laminate so that it can slide along the lamination direction. Therefore, since the slide of the battery cell is permitted when the battery cell expands, the bending of the laminate due to the expansion of the battery cell is suppressed. Furthermore, in this battery module, the fixing member fixes the laminated body to the member to be fixed between the constraint fixing mechanisms. Therefore, bending of the laminate when vibration or impact is applied to the battery module is suppressed. An example of the member to be fixed includes a battery pack housing including a plurality of battery modules.

  In the battery module according to the present invention, the fixing member is formed of a plate-like portion arranged together with the battery cells along the first direction, and is formed integrally with the plate-like portion, and is fixed to the fixed member to be a laminated body. And a first fixing part that fixes to the fixed member. Thus, a fixing member having a plate-like portion (plate-like portion) can be used for fixing the laminate.

  In the battery module according to the present invention, the first fixing portion is provided with a first through hole, and the first fixing portion is fixed to the member to be fixed by a bolt inserted into the first through hole. The 1 through hole may be a long hole extending along the first direction. In this case, since the first through hole (bolt hole) used for fixing the fixing member is a long hole extending in the stacking direction, the fixing member slides due to a change in the relative position of the first through hole with respect to the bolt. Permissible. In other words, when the battery cell expands, the sliding of the battery cell is not inhibited by the sliding of the fixing member. For this reason, it is possible to reliably suppress the bending of the laminate due to the expansion of the battery cells.

  In the battery module according to the present invention, each of the restraint and fixing mechanisms is arranged along with the battery cells along the first direction, and a restraint portion that applies restraint load to the laminate, and the laminate by being secured to the fixed member. And a second fixing portion that fixes the fixed member to the fixed member.

  In the battery module according to the present invention, at least one of the restraining and fixing mechanisms includes an elastic member arranged between the restraining portion and the laminated body, and the restraining and fixing mechanism is along the first direction of the elastic member. Depending on the deformation, the battery cell may be allowed to slide. As described above, if the battery cell can be slid by deformation of the elastic member, it is possible to reliably suppress the bending of the laminated body due to the expansion of the battery cell. On the other hand, in this case, for example, when the battery cell is expanded or when a vibration or impact is applied to the battery module, the elastic member shears and deforms, so that the elastic member side portion of the laminate is easily bent. For this reason, it is more effective to suppress bending by the fixing member.

  In the battery module according to the present invention, each of the restraining and fixing mechanisms may include an elastic member. In this case, an elastic member is arrange | positioned at the both ends of a laminated body. Therefore, the bending of the laminated body due to the expansion of the battery cell can be more reliably suppressed. Further, the effectiveness of suppressing the bending by the fixing member is further high. Furthermore, in this case, since the slide of the battery cell is allowed by the elastic members on both ends of the laminated body (that is, distributed on both sides), it is possible to reduce the slide amount of each battery cell. is there.

  In the battery module according to the present invention, the fixing member may be arranged such that the plate-like portion is interposed between the laminate and the elastic member. In this case, it is possible to effectively suppress the bending of the elastic member side portion of the laminate.

  In the battery module according to the present invention, the fixing member may be arranged such that the plate-like portion is interposed between the battery cells. For example, when the rigidity of the elastic member is large and difficult to be sheared and the entire rigidity of the laminated body is low and easily bent, the fixing member is separated from the elastic member and disposed between the battery cells in this way. The bending of the body can be effectively suppressed.

  In the battery module according to the present invention, the second fixing portion is provided with a second through hole, and the second fixing portion is fixed to the member to be fixed by a bolt inserted into the second through hole. The two through holes are elongated holes extending along the first direction, and the restraint fixing mechanism allows the battery cell to slide by a change in the relative position of the second through hole with respect to the bolt along the first direction. May be. In this case, the battery cell can be slidable using the second fixing portion of the restraint fixing mechanism. That is, it is possible to suppress the bending of the stacked body due to the expansion of the battery cell without using an elastic member. However, the sliding of the battery cell may be reliably allowed by using the elastic member together.

  In the battery module according to the present invention, the stacked body includes a first part including a part of the plurality of battery cells and a second part including a remaining part of the plurality of battery cells, and the fixing member includes the first part. The restraint / fixing mechanism is disposed between the part and the second part, and the restraint / fixing mechanism applies a restraint load to the first part by the one restraint and the fixing member by fastening each of the restraint to the fixing member. At the same time, a restraining load may be applied to the second portion by the other restraining portion and the fixing member. In this way, if the fastening portion is fastened using the fixing member disposed between the first portion and the second portion of the laminate, the restraint portions at both ends of the laminate are fastened. Thus, the bolt for fastening can be shortened. Thereby, cost can be reduced.

  The battery module according to the present invention includes two or more fixing members, and battery cells may be interposed between the fixing members. Thus, if two or more fixing members are used, the bending of the laminate can be more reliably suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the battery module which can suppress the bending of the laminated body of a battery cell can be provided.

It is a figure which shows the battery module which concerns on this embodiment. It is a disassembled perspective view which shows the battery unit shown by FIG. It is a figure which shows a part of battery module shown by FIG. It is a figure which shows the battery module which concerns on this embodiment. It is a figure which shows the battery module which concerns on this embodiment. It is a figure which shows the battery module which concerns on this embodiment. It is a figure which shows the battery module which concerns on this embodiment.

Hereinafter, an embodiment of a battery module will be described with reference to the drawings. In the description of the drawings, the same elements or corresponding elements may be denoted by the same reference numerals, and redundant description may be omitted. Each drawing may show an orthogonal coordinate system S composed of an X axis, a Y axis, and a Z axis.
[First Embodiment]

  FIG. 1 is a diagram illustrating a battery module according to the present embodiment. FIG. 1A is a schematic side view of a battery module, and FIG. 1B is a graph showing characteristics relating to bending. As shown in FIG. 1, the battery module 1 is fixed to a fixed member M such as a casing of a battery pack, for example. The battery module 1 includes a laminated body 10, a pair of constraint fixing mechanisms 20, a fastening member 30, and a fixing member 40. The stacked body 10 includes a plurality of (for example, 10) battery units 11 stacked on each other along a first direction (here, the X-axis direction).

  FIG. 2 is an exploded perspective view showing the battery unit shown in FIG. As shown in FIG. 2, each battery unit 11 includes a battery cell 12, a cell holder 13, and a heat transfer plate 14. Therefore, the stacked body 10 includes a plurality of (for example, ten) battery cells 12 stacked on each other along the first direction. The battery cell 12 is a nonaqueous electrolyte secondary battery such as a lithium-in secondary battery, for example.

  The battery cell 12 includes an electrode assembly 15, a rectangular parallelepiped case 16 that houses the electrode assembly 15, and a pair of terminals 17 that are electrically connected to electrodes (each of a positive electrode and a negative electrode) of the electrode assembly 15. ,including. The electrode assembly 15 includes a plurality of positive electrodes (not shown) and a negative electrode (not shown), and a separator (not shown) disposed between the positive electrode and the negative electrode. The positive electrode and the negative electrode are alternately stacked via separators along the first direction. The case 16 extends along a pair of side surfaces 16a along the first direction (stacking direction of the battery cells 12) and a direction intersecting the first direction (here, the Y-axis direction and the Z-axis direction), and the side surfaces 16a And a pair of side surfaces 16b connecting the two.

  The cell holder 13 holds the battery cell 12. More specifically, the cell holder 13 includes a pair of side wall portions 13a facing each other, a back surface portion 13b, and a bottom wall portion 13c. The side wall portion 13a has a rectangular plate shape. The back surface portion 13b has a rectangular plate shape and connects the side wall portions 13a to each other at one end portion in the longitudinal direction of the side wall portion 13a. The bottom wall portion 13c has a rectangular plate shape and connects the side wall portions 13a to each other at the other end portion in the longitudinal direction of the side wall portion 13a.

  In the cell holder 13, a rectangular parallelepiped space portion in which the battery cells 12 are fitted is defined by the side wall portion 13a, the back surface portion 13b, and the bottom wall portion 13c. The side wall portions 13a are respectively disposed on the side surfaces 16a of the case 16 when the battery cells 12 are fitted in the space portions. Similarly, the back surface portion 13 b is disposed on the side surface 16 b of the case 16.

  A pair of projecting portions 13p are provided on the back surface portion 13b. In addition, a pair of projecting portions 13p is also provided at a connection portion between the bottom wall portion 13c and the side wall portion 13a. The protruding portion 13p has a rectangular parallelepiped shape. The protruding portion 13p is formed with an insertion hole 13h along the first direction. As will be described later, the bolt 31 of the fastening member 30 is inserted into the insertion hole 13h.

  The heat transfer plate 14 includes a rectangular plate-like main body portion 14a and a rectangular plate-like extension portion 14b. The heat transfer plate 14 is formed in an L-shaped plate shape by the main body portion 14a and the extending portion 14b. The main body portion 14a is disposed on the side surface 16b of the battery cell 12 (case 16). The extending portion 14b extends from the main body portion 14a along the first direction, and is disposed on the side surface 16a of the battery cell 12 (case 16). In particular, the extending portion 14 b is disposed on the side surface 16 a via the side wall portion 13 a of the cell holder 13.

  The heat transfer plate 14 contacts the battery cell 12 in the main body portion 14a, and contacts the fixed member M on the surface of the extending portion 14b opposite to the side wall portion 13a (not limited to direct contact, but a predetermined In some cases via the heat conducting member). Thereby, the heat transfer plate 14 thermally connects the battery cell 12 and the fixed member M. In particular, the surface of the extending portion 14b opposite to the side wall portion 13a is a heat transfer surface 14s that thermally connects the battery cell 12 to the fixed member M. That is, the battery unit 11 is disposed such that the heat transfer surface 14s faces the fixed member M.

  With continued reference to FIG. The constraint fixing mechanism 20 applies a constraint load to the stacked body 10 along the first direction. Moreover, the restraint fixing mechanism 20 fixes the laminated body 10 to the fixed member M as a whole at both ends of the laminated body 10 in the first direction. More specifically, the constraint fixing mechanism 20 fixes the stacked body 10 to the fixed member M in the first direction and the second direction (here, the Y-axis direction) intersecting the first direction. The second direction is a direction that intersects the first direction and is a direction away from the fixed member M.

  On the other hand, for example, when the battery cell 12 expands, the restraint fixing mechanism 20 allows the battery cell 12 (battery unit 11) to slide along the first direction while resisting the restraint load by the amount of expansion. The laminated body 10 is fixed to the fixed member M. Here, the battery cell 12 is slidable means that the battery cell 12 is positioned in the first direction when the battery cell 12 is initially restrained when the battery module 1 is assembled, and the battery cell 12 is slidable. This means that when the battery cell 12 expands according to the deterioration of the cell 12 or the like, the battery cell 12 can move along the first direction by the amount of expansion. The constraint fixing mechanism 20 will be described in more detail in detail.

  The constraint fixing mechanism 20 </ b> A located on one end side of the stacked body 10 of the pair of constraint fixing mechanisms 20 includes a bracket 21 and an elastic member 22. The restraint fixing mechanism 20 </ b> B located on the other end side of the stacked body 10 of the pair of restraint fixing mechanisms 20 includes a bracket 21. Here, the constraint fixing mechanism 20 </ b> A is the bracket 21 and the elastic member 22, and the constraint fixing mechanism 20 </ b> B is the bracket 21. For this reason, in the battery module 1, the elastic member 22 is disposed only on one end side of the stacked body 10.

  The bracket 21 has a plate-like restraint portion 21a extending along the second direction and the third direction intersecting the first direction, and a plate-like shape extending from the restraint portion 21a toward the outside of the stacked body 10 along the first direction. The fixed part (second fixed part) 21b. Here, the bracket 21 is formed in an L-shaped plate shape by the restraining portion 21a and the fixing portion 21b. The restraint portions 21a are arranged together with the battery cells 12 along the first direction. A through hole is formed in the restraining portion 21a. The restraining portions 21a are fastened to each other by the bolts 31 of the fastening members 30 inserted through the through holes, thereby applying a restraining load to the stacked body 10 along the first direction.

  A through hole is formed in the fixing portion 21b. The fixing part 21b fixes the laminated body 10 to the fixed member M by being fixed to the fixed member M by the bolt B inserted through the through hole in a state where the restricting part 21a restricts the laminated body 10. . In this state, the elastic member 22 is restrained together with the stacked body 10. Therefore, when the battery cell 12 expands, for example, the restraint fixing mechanism 20 (here, the restraint fixing mechanism 20A) deforms the elastic member 22 along the first direction by the amount of the expansion. Allow sliding along the first direction.

  The fastening member 30 includes a plurality of (for example, four) bolts 31 and a number of nuts 32 corresponding to the number of bolts 31. The bolt 31 is inserted into the through hole of the restraining portion 21 a of the bracket 21 and the insertion hole 13 h of the protruding portion 13 p of the cell holder 13. The nut 32 is screwed into the end portion of the bolt 31 in a state of being inserted through the through hole and the insertion hole 13h of the restraining portion 21a. Thereby, the fastening member 30 fastens the restraining portions 21a to each other.

  FIG. 3 is a diagram illustrating a part of the battery module illustrated in FIG. 1. 3A is a plan view, and FIG. 3B is an enlarged cross-sectional view of a region AR in FIG. As shown in FIGS. 1 and 3, the fixing member 40 is disposed between the pair of constraint fixing mechanisms 20 </ b> A and 20 </ b> B, and fixes the stacked body 10 to the fixed member M. The fixing member 40 is formed integrally with the plate-like portion 41 and the plate-like portion 41 arranged together with the battery cells 12 along the first direction, and is laminated in at least the second direction by being fixed to the fixed member M. And a pair of fixing parts (first fixing parts) 42 for fixing the body 10 to the fixed member M. The plate-like portion 41 extends along the second direction and the third direction.

  Here, the fixing member 40 is disposed such that the plate-like portion 41 is interposed between the laminate 10 and the elastic member 22. That is, here, the fixing member 40 is disposed on one end side of the stacked body 10 in the first direction. The plate-like portion 41 is provided with a through hole through which the bolt 31 is inserted. Thereby, the plate-like portion 41 functions to suppress the bending of the laminated body 10 (the bending of the bolt 31) within the clearance range between the inner surface of the through hole and the outer peripheral surface of the bolt 31. Further, the plate-like portion 41 has a function of equalizing the restraining load from the elastic member 22 to the laminated body 10 in a plane intersecting the first direction. That is, the fixing member 40 has a function as a middle plate disposed between the laminate 10 and the elastic member 22.

  The fixing portion 42 protrudes on both sides of the plate-like portion 41 on the lower end side of the plate-like portion 41. Each of the fixed portions 42 is provided with a through hole (first through hole) 42h. The fixing portion 42 is fixed to the fixed member M by a bolt B inserted through the through hole 42h. The through hole 42h is a long hole extending along the first direction. Accordingly, the fixing portion 42 allows a relative position change along the first direction of the through hole 42h with respect to the bolt B in a state where the fixing portion 42 is fixed to the fixed member M by the bolt B at least in the second direction.

  Thus, the fixing member 40 is slidable along the first direction by a distance corresponding to the dimension of the through hole 42h in a state where the fixing member 40 is fixed to the member M to be fixed at least in the second direction. Therefore, when the battery cell 12 slides due to the expansion of the battery cell 12 as described above, the fixing member 40 slides in the same direction together with the battery cell 12 while maintaining the fixation of the stacked body 10 in the second direction. .

  As described above, in the battery module 1, the restraint fixing mechanism 20 applies a restraining load to the stacked body 10 including the plurality of battery cells 12 stacked on each other along the first direction (stacking direction). At the same time, the stacked body 10 is fixed to the fixed member M at both ends of the stacked body 10 so that the battery cell 12 can slide along the stacking direction against a restraining load. Therefore, since the slide of the battery cell 12 is permitted when the battery cell 12 expands, the bending of the stacked body 10 due to the expansion of the battery cell 12 is suppressed. Furthermore, in the battery module 1, the fixing member 40 fixes the laminated body 10 to the member to be fixed M between the constraint fixing mechanisms 20. Therefore, the bending of the laminate 10 when vibration or impact is applied to the battery module 1 is suppressed.

  In particular, in the battery module 1, the restraint fixing mechanism 20 is fixed to the fixed member M and the restraint portion 21 a that is arranged along with the battery cells 12 along the first direction and applies a restraint load to the stacked body 10. And a fixing portion 21b for fixing the laminated body 10 to the fixed member M. The restraint fixing mechanism 20 </ b> A includes an elastic member 22 disposed between the restraint portion 21 a and the stacked body 10. Thereby, the restraint fixing mechanism 20 </ b> A allows the battery cell 12 to slide by deformation along the first direction of the elastic member 22.

  As described above, if the battery cell 12 can be slid by deformation of the elastic member 22, it is possible to reliably suppress the bending of the stacked body 10 due to the expansion of the battery cell 12. On the other hand, in this case, as shown by the broken line in FIG. 1B, for example, when the battery cell 12 is expanded or when vibration or impact is applied to the battery module 1, the elastic member 22 undergoes shear deformation. As a result, the elastic member 22 side portion of the laminate 10 is easily bent (the amount of deflection is increased). For this reason, it is more effective to suppress the bending by the fixing member 40.

  In particular, in the battery module 1, the fixing member 40 is formed integrally with the plate-like portion 41 and the plate-like portion 41 arranged together with the battery cells 12 along the first direction, and is fixed to the fixed member M. The fixing part 42 which fixes the laminated body 10 to the to-be-fixed member M by this. In the battery module 1, the fixing member 40 is disposed such that the plate-like portion 41 is interposed between the laminate 10 and the elastic member 22. For this reason, as shown by the solid line in FIG. 1B, it is possible to effectively suppress the bending of the laminated body 10 on the elastic member 22 side.

In the battery module 1, the fixing portion 42 of the fixing member 40 is provided with a through hole 42 h, and the fixing portion 42 is fixed to the fixed member M by a bolt B inserted through the through hole 42 h. Yes. The through hole 42h is a long hole extending along the first direction. For this reason, sliding of the fixing member 40 is permitted by the change in the relative position of the bolt B with respect to the through hole 42h (change along the first direction). That is, when the battery cell 12 is expanded, the sliding of the battery cell 12 is not hindered by the sliding of the fixing member 40. For this reason, the bending of the laminated body 10 resulting from expansion | swelling of the battery cell 12 can be suppressed reliably.
[Second Embodiment]

  Subsequently, a second embodiment of the battery module will be described. FIG. 4 is a diagram illustrating the battery module according to the present embodiment. FIG. 4A is a schematic side view of the battery module, and FIG. 4B is a graph showing characteristics relating to bending. As shown in FIG. 4, the battery module 2 according to the present embodiment differs from the battery module 1 according to the first embodiment in the position of the fixing member 40. Other points of the battery module 2 are the same as those of the battery module 1.

  More specifically, in the battery module 2, the fixing member 40 is disposed such that the plate-like portion 41 is interposed between the battery cells 12. Here, the fixing member 40 has the plate-like portion 41 positioned at the center of the laminate 10 in the first direction (that is, the number of battery cells 12 on both sides of the plate-like portion 41 is the same). Has been placed. Thereby, as shown by the solid line in FIG. 4B, the bending of the laminate 10 is suppressed at the position corresponding to the fixing member 40. As shown in the figure, even when the fixing member 40 is arranged at the center of the laminated body 10 (solid line), the elastic member 22 is compared with the case where the fixing member 40 shown by the broken line is not used. Side deflection (and overall deflection) is also suppressed.

Even in such a battery module 2, the same effects as in the battery module 1 can be obtained. In particular, the battery module 2 is effective when, for example, the elastic member 22 has a relatively large rigidity and is difficult to undergo shear deformation, and the entire laminated body 10 has a low rigidity and is easily bent. That is, in such a case, it is possible to effectively suppress the entire bending of the laminated body 10 by disposing the fixing member 40 between the battery cells 12 apart from the elastic member 22 as in the battery module 2. . The position of the fixing member 40 is not limited to the center of the stacked body 10. That is, the fixing member 40 may be disposed so as to be biased toward one side (or the other side) of the stacked body 10 in the first direction.
[Third Embodiment]

  Subsequently, a third embodiment of the battery module will be described. FIG. 5 is a diagram illustrating the battery module according to the present embodiment. FIG. 5A is a schematic side view of the battery module, and FIG. 5B is a graph showing characteristics relating to bending. As shown in FIG. 5, the battery module 3 according to the present embodiment differs from the battery module 1 according to the first embodiment in the position and number of the fixing members 40. Other points of the battery module 3 are the same as those of the battery module 1.

  More specifically, the battery module 3 includes two fixing members 40. Here, the two fixing members 40 are arranged such that the plate-like portion 41 is interposed between the battery cells 12. One fixing member 40 is disposed such that the plate-like portion 41 is positioned at the center of the laminate 10 in the first direction. Further, the other fixing member 40 is disposed such that the plate-like portion 41 is located on one end side (elastic member 22 side) from the center of the stacked body 10 in the first direction. A plurality of battery cells 12 are interposed between the fixing members 40.

  Also in such a battery module 3, the same effect as the battery module 1 according to the first embodiment and the battery module 2 according to the second embodiment can be obtained. In particular, the battery module 3 includes two fixing members 40, and the battery cells 12 are interposed between the fixing members 40. Thus, if two fixing members 40 are used, the bending of the laminated body 10 can be more reliably suppressed as shown by the solid line in FIG.

In the battery module 3, the number and positions of the fixing members 40 are not limited to the example in FIG. The battery module 3 may include, for example, three or more fixing members 40 (that is, the number of fixing members 40 may be two or more). Further, for example, one fixing member 40 is disposed so that the plate-like portion 41 is interposed between the battery cells 12, and another fixing member 40 is arranged such that the plate-like portion 41 is the laminate 10 and the elastic member. It may be arranged so as to be interposed between the two. Further, the position of the one fixing member 40 may not be the center of the laminate 10.
[Fourth Embodiment]

  Then, 4th Embodiment of a battery module is described. FIG. 6 is a diagram illustrating the battery module according to the present embodiment. 6A is a schematic side view of the battery module, and FIG. 6B is an enlarged cross-sectional view of a region BR in FIG. 6A. As shown in FIG. 6, the battery module 4 according to the present embodiment differs from the battery module 2 according to the second embodiment in the configuration of the restraint fixing mechanism 20 and the configuration of the fixing member 40. Other points of the battery module 4 are the same as those of the battery module 2.

  More specifically, in the battery module 4, the constraint fixing mechanism 20 </ b> B of the constraint fixing mechanism 20 also includes the bracket 21 and the elastic member 22. That is, in the battery module 4, each of the constraint fixing mechanisms 20 includes the elastic member 22. Therefore, here, the elastic member 22 is disposed on both ends of the laminate 10. For this reason, when the battery cell 12 expands, for example, the restraint fixing mechanism 20B also deforms the elastic member 22 along the first direction by the amount of the expansion, thereby sliding the battery cell 12 along the first direction. Allow.

  Here, the bracket 21 includes a fixing portion (second fixing portion) 21c instead of the fixing portion 21b. The fixing portion 21c has a plate shape extending along the first direction from the restraining portion 21a toward the outside of the stacked body 10, similarly to the fixing portion 21b. Therefore, the bracket 21 is also formed in an L-shaped plate shape by the restraining portion 21a and the fixing portion 21c. A through hole (second through hole) 21h is formed in the fixing portion 21c. The fixing part 21c fixes the laminated body 10 to the fixed member M by being fixed to the fixed member M by a bolt C inserted into the through hole 21h in a state where the restricting part 21a holds the laminated body 10. To do.

  In particular, the through hole 21h is a long hole extending along the first direction. Therefore, the restraint fixing mechanisms 20A and 20B are relatively positioned in the first direction of the through hole 21h with respect to the bolt C in the state where the bracket 21 is fixed to the fixed member M by the bolt C at least in the second direction. Allow changes.

  Thereby, the bracket 21 (restraining portion 21a) is slidable along the first direction by a distance corresponding to the dimension of the through hole 21h in a state where the bracket 21 (the restraining portion 21a) is fixed to the fixed member M at least in the second direction. . Therefore, when the battery cell 12 slides due to the expansion of the battery cell 12, the bracket 21 slides in the same direction together with the battery cell 12 while maintaining the fixation of the stacked body 10 in the second direction. This configuration will be specifically described.

  As shown in FIG. 6B, the bolt C used to fix the fixing portion 21c connects the head portion C1, the shaft portion C2 formed with the thread, and the head portion C1 and the shaft portion C2. Connecting portion C3. The connection portion C3 has a column shape that is smaller than the head portion C1 and larger than the shaft portion C2. That is, the bolt C is a stepped bolt. A thread is not formed in the connection portion C3. In such a state that the bolt C is inserted into the through hole 21h, the shaft portion C2 is a screw of the fixed member M until the stepped portion between the shaft portion C2 and the connecting portion C3 contacts the fixed member M. Screwed into the hole.

  Thereby, the distance from the surface of the fixing portion 21c (the surface opposite to the fixed member M) to the back surface of the head C1 (the surface facing the surface of the fixing portion 21c) is the thickness of the fixing portion 21c and the connecting portion. It becomes constant according to the length of C3. An elastic member D such as a spring is disposed between the front surface of the fixed portion 21c and the back surface of the head C1. The elastic member D is given a compression amount corresponding to the certain distance. Thereby, the force which fixes the fixing | fixed part 21c becomes constant according to the compression amount of the elastic member D. FIG. Accordingly, the design of the elastic member D allows the bracket 21 to withstand the load during the initial compression of the battery cell 12 without sliding, and to slide in the first direction when the battery cell 12 subsequently expands. Can be designed in fixed form.

  Further, in the battery module 4, the fixing member 40 is disposed so that the plate-like portion 41 is interposed between the battery cells 12. In this example, the fixing member 40 is disposed such that the plate-like portion 41 is located at the center of the stacked body 10. On the other hand, the through hole 42 h provided in the fixing portion 42 of the fixing member 40 is not a long hole but has a shape corresponding to the shape of the bolt B. Therefore, the relative position of the through hole 42h with respect to the bolt B does not change. That is, in the battery module 4, the fixing member 40 does not slide. This is because the displacement due to the expansion of the battery cell 12 can be permitted by the elastic members 22 and the restraint fixing mechanism 20 on both ends of the laminated body 10.

  Even in such a battery module 4, the same effects as those of the battery module 2 according to the second embodiment can be obtained except for the effects due to the fixing member 40 being slidable. In particular, in the battery module 4, each of the restraint and fixing mechanisms 20 includes the elastic member 22, and the elastic member 22 is disposed on both ends of the stacked body 10. For this reason, the bending of the laminated body 10 resulting from expansion | swelling of the battery cell 12 can be suppressed more reliably.

  Moreover, in the battery module 4, since the elastic member 22 which has a possibility of carrying out a shear deformation is arrange | positioned at the both ends of the laminated body 10, the effectiveness of suppressing the bending of the laminated body 10 by the fixing member 40 is high. . In the battery module 4, the slide of the battery cells 12 is allowed by the elastic members 22 on both ends of the stacked body 10 (that is, distributed on both sides), so that the slide amount of each battery cell 12 is reduced. Is possible.

  Further, in the battery module 4, the fixing portion 21c of the restraint fixing mechanism 20 is provided with a through hole 21h, and the fixing portion 21c is fixed to the fixed member M by a bolt C inserted into the through hole 21h. The The through hole 21h is a long hole extending along the first direction. The restraint fixing mechanism 20 allows the battery cell 12 to slide by a change in the relative position along the first direction of the through hole 21h with respect to the bolt C.

Thus, in the battery module 4, the battery cell 12 can be slidable using the fixing portion 21 c of the restraint fixing mechanism 20. That is, in the example of FIG. 6, the elastic member 22 is used, but even when the elastic member 22 is not used, the bending of the stacked body 10 due to the expansion of the battery cell 12 can be suppressed. However, if the elastic member 22 is also used as in the example of FIG. 6, the battery cell 12 can be reliably slid.
[Fifth Embodiment]

  Subsequently, a fifth embodiment of the battery module will be described. FIG. 7 is a diagram showing the battery module according to the present embodiment. As shown in FIG. 7, the battery module 5 according to the present embodiment is different from the battery module 4 according to the fourth embodiment in the restraint mode of the laminated body 10 and the fixing member instead of the fixing member 40. 50 is different. Other points of the battery module 5 are the same as those of the battery module 4. This will be described more specifically.

  In the battery module 5, the stacked body 10 includes a first portion 10 </ b> A including a part of the plurality of battery cells 12 and a second portion 10 </ b> B including the remaining part of the plurality of battery cells 12. As an example, here, the number of battery cells 12 included in the first portion 10A is the same as the number of battery cells 12 included in the second portion 10B. That is, here, the laminated body 10 is divided into two parts, that is, a first part 10A and a second part 10B.

  The fixing member 50 is disposed between the first portion 10A and the second portion 10B. More specifically, the fixing member 50 is formed integrally with the plate-like portion 51 and the plate-like portion 51 arranged together with the battery cells 12 along the first direction, and is fixed to the fixed member M. And a fixing part (first fixing part) 52 for fixing the laminated body 10 to the fixed member M. The fixing member 50 is disposed such that the plate-like portion 51 is positioned between the first portion 10A and the second portion 10B.

  That is, here, the fixing member 50 is disposed such that the plate-like portion 51 is interposed between the battery cell 12 belonging to the first portion 10A and the battery cell 12 belonging to the second portion 10B. The fixing portion 52 is fixed to the fixed member M by inserting the bolt B. The insertion hole of the bolt B provided in the fixing portion 52 is not a long hole but a shape corresponding to the shape of the bolt B. Therefore, in the battery module 5, the fixing member 50 does not slide.

  Then, the restraint fixing mechanism 20 fastens each restraint portion 21a to the plate-like portion 51 of the fixing member 50, whereby one restraint portion 21a (here, the restraining portion 21a of the restraint fixing mechanism 20A) and the fixing member 50 are fixed. The second portion 10B is loaded with a restraining load by the other restraining portion 21a (here, the restraining portion 21a of the restraining and fixing mechanism 20B) and the fixing member 50. Each of the restraining portions 21 a is fastened to the fixing member 50 by the bolt 31 of the fastening member 30. The front end of the bolt 31 opposite to the head is screwed into the screw hole of the fixing member 50.

  Also in such a battery module 5, the same effect as the battery module 4 which concerns on 4th Embodiment can be show | played. In particular, in the battery module 5, the stacked body 10 includes a first portion 10 </ b> A including a part of the plurality of battery cells 12 and a second portion 10 </ b> B including a remaining part of the plurality of battery cells 12. The member 50 is disposed between the first portion 10A and the second portion 10B. Then, the restraint fixing mechanism 20 fastens each of the restraining portions 21a to the fixing member 50, thereby applying a restraining load to the first portion 10A by the one restraining portion 21a and the fixing member 50, and the other restraining portion. A restraint load is applied to the second portion 10 </ b> B by 21 a and the fixing member 50.

  Thus, in the battery module 5, if the restraint portion 21 a is fastened using the fixing member 50 arranged between the first portion 10 </ b> A and the second portion 10 </ b> B of the laminate 10, The bolt 31 for fastening can be shortened compared with the case where the restraining parts 21a of both ends are fastened. Thereby, cost can be reduced. In addition, productivity is improved.

  The above embodiment describes one embodiment of the battery module according to the present invention. Therefore, the battery module according to the present invention is not limited to the battery modules 1 to 5 described above. In the battery module according to the present invention, the above-described battery modules 1 to 5 can be arbitrarily modified without changing the gist of each claim.

  For example, the battery modules 1 to 5 described above can apply the configurations of the respective parts to each other. Specifically, for example, a configuration using a plurality of fixing members 40 as in the battery module 3 may be applied to the battery modules 1, 2, 4, and 5. Moreover, you may apply the structure which each of restraint fixing mechanism 20A, 20B has the elastic member 22, and the fixing | fixed part 21c like the battery modules 4 and 5 with respect to the battery modules 1-3.

  Conversely, a configuration in which only one restraint fixing mechanism 20 </ b> A of the restraint fixing mechanisms 20 includes the elastic member 22 as in the battery modules 1 to 3 may be applied to the battery modules 4 and 5. Further, in the battery modules 4 and 5, none of the restraint fixing mechanism 20 may have the elastic member 22. Moreover, the structure which arrange | positions the fixing member 40 so that the plate-shaped part 41 may interpose between the laminated body 10 and the elastic member 22 like the battery module 1 with respect to the battery modules 2-5 is applied. May be. Furthermore, the deformation of the battery modules 1 to 5 is not limited to these aspects, and the configurations of the respective units can be applied to each other arbitrarily.

  DESCRIPTION OF SYMBOLS 1-5 ... Battery module, 10 ... Laminated body, 10A ... 1st part, 10B ... 2nd part, 12 ... Battery cell, 20, 20A, 20B ... Restraint fixing mechanism, 21a ... Restraint part, 21b, 21c ... Fixing part (Second fixing part), 21h ... through hole (second through hole), 22 ... elastic member, 40, 50 ... fixing member, 41, 51 ... plate-like part, 42, 52 ... fixing part (first fixing part) 42h ... through hole (first through hole), M ... fixed member.

Claims (11)

A laminate including a plurality of battery cells laminated to each other along the first direction;
A pair of restraint and fixing mechanisms for applying a restraining load to the laminate along the first direction and for fixing the laminate to a member to be fixed at both ends of the laminate in the first direction; ,
A fixing member disposed between the pair of restraint fixing mechanisms and fixing the laminated body to the fixed member;
The restraint fixing mechanism fixes the stacked body to the fixed member so that the battery cell can slide along the first direction while resisting the restraining load.
Battery module. The fixing member is formed integrally with the plate-like portion arranged along with the battery cells along the first direction, and the plate-like portion, and is fixed to the fixing member to thereby fix the laminate to the covering member. A first fixing portion that is fixed to the fixing member,
The battery module according to claim 1. The first fixing portion is provided with a first through hole,
The first fixing portion is fixed to the fixed member by a bolt inserted into the first through hole,
The first through hole is an elongated hole extending along the first direction.
The battery module according to claim 2. The restraint and fixing mechanism is arranged with the battery cells along the first direction, and a restraint unit that loads the restraint load on the laminate, and the restraint and fixing mechanism is secured to the member to be secured. A second fixing portion for fixing to the fixed member,
The battery module according to claim 2 or 3. At least one of the restraint and fixing mechanism includes an elastic member disposed between the restraint portion and the laminate,
The restraint fixing mechanism allows the slide of the battery cell by deformation along the first direction of the elastic member.
The battery module according to claim 4. Each of the constraint fixing mechanisms includes the elastic member,
The battery module according to claim 5. The fixing member is disposed such that the plate-like portion is interposed between the laminated body and the elastic member.
The battery module according to claim 5 or 6. The fixing member is disposed so that the plate-like portion is interposed between the battery cells.
The battery module as described in any one of Claims 4-7. The second fixing part is provided with a second through hole,
The second fixing portion is fixed to the fixed member by a bolt inserted into the second through hole,
The second through hole is an elongated hole extending along the first direction,
The restraint fixing mechanism allows the slide of the battery cell by a change in relative position along the first direction of the second through hole with respect to a bolt.
The battery module as described in any one of Claims 4-8. The laminate includes a first part including a part of the plurality of battery cells, and a second part including a remaining part of the plurality of battery cells,
The fixing member is disposed between the first portion and the second portion;
The restraint and fixing mechanism is configured to load the restraint load on the first portion by one of the restraining portions and the fixing member by fastening each of the restraining portions to the fixing member, and the other restraining portion. And the restraining load is applied to the second portion by the fixing member.
The battery module as described in any one of Claims 4-9. Comprising two or more of the fixing members;
The battery cells are interposed between the fixing members,
The battery module as described in any one of Claims 1-10.

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