JP2018026271A - Battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module capable of preventing deformation and breakage of an end plate and a binding member at the time of battery cell expansion, without increasing the number of components.SOLUTION: A battery module 1 includes an array 2 of multiple battery cells 3, an elastic body 4 placed at one end of the array 2, a pair of end plates 5, 6 clamping the array 2 and elastic body 4 in the arrangement direction of the battery cells 3, and a binding member 7 for adding a binding load to the array 2 and elastic body 4 clamped by the end plates 5, 6. On the outer surface side of the end plate 5 abutting against the elastic body 4, a protrusion 23a extending in the height direction with one marginal part 5a as a base, and a protrusion 24a extending in the width direction crossing the height direction are provided, and on the inner surface side, one or more recesses 23b, 24b are provided corresponding to the abutment region against the elastic body 4.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a battery module.

  As a conventional battery module, there exists a thing of patent document 1, for example. The battery module of Patent Document 1 includes an array formed by arranging battery cells held by a battery holder, a pair of end plates disposed on both sides of the array, and an array between the array and the end plate. And an arrayed body sandwiched between a pair of end plates and a restraining member for applying a restraining load to the elastic body.

JP 2009-81056 A JP 2007-42648 A

  In the battery module as described above, the battery cell may expand with deterioration. When expansion occurs in the battery cell, a rapid increase in the restraining load applied to each battery cell is suppressed by the compression of the elastic body. However, if the compression amount of the elastic body exceeds a preset compression margin, the increase amount of the restraint load with respect to the expansion amount of the battery cell becomes excessive, and the restraint member may be deformed or damaged.

  For such a problem, for example, a configuration in which a reinforcing member is fixed to an end plate, such as a battery module described in Patent Document 2, can be considered. However, if the amount of compression of the elastic body exceeds the compression margin, the restraint load increases rapidly with respect to the amount of expansion of the battery cell. Therefore, simply strengthening the end plate with a reinforcing member does not provide sufficient strength to the end plate. It is possible to do. Moreover, there is also a problem that the number of parts of the battery module increases due to the use of the reinforcing member.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a battery module that can prevent deformation and breakage of an end plate and a restraining member during battery cell expansion without increasing the number of parts. And

  A battery module according to one aspect of the present invention includes an array formed by arranging a plurality of battery cells, an elastic body disposed at one end of the array, and the array and the elastic body sandwiched in the array direction of the battery cells. A pair of end plates, and a restraining member that applies a restraining load to the arrayed body and the elastic body sandwiched between the pair of end plates, and is used for fixing to one edge of the pair of end plates. A fixed piece is provided on each outer surface of the end plate that comes into contact with the elastic body. The first protrusion extends in the height direction with one edge as a base, and the second protrusion extends in the width direction intersecting the height direction. One or a plurality of recesses are provided on the inner surface side of the end plate that contacts the elastic body, corresponding to the contact area with the elastic body.

  When the battery cell expands, the end plate is subject to an indentation deformation that falls outward with one edge provided with a fixing piece as a fulcrum, and a bending deformation that protrudes outward in the width direction. Can be considered. On the other hand, in this battery module, the strength against falling-down deformation is ensured by the first convex portion provided in the height direction on the outer surface side of the end plate, and the second convex portion provided in the width direction is curved. Strength against deformation is ensured. Further, in this battery module, a concave portion is provided in the contact area with the elastic body on the inner surface side of the end plate. Since the recess serves as a clearance for the elastic body when the battery cell expands, the amount of increase in the restraining load relative to the expansion amount of the battery cell can be reduced. Therefore, in this battery module, it is possible to prevent deformation and breakage of the end plate and the restraining member when the battery cell is expanded without increasing the number of parts.

  In addition, the battery module includes a first concavo-convex portion in which the first convex portion and the concave portion are integrated with each other, and a second concavo-convex portion in which the second convex portion and the concave portion are integrated with each other. Also good. By employing such a first uneven portion and a second uneven portion, the end plate can be easily formed using press molding or the like.

  In addition, the end plate is provided with an insertion hole through which a restraining bolt constituting the restraining member is inserted. The end plate has an ear portion provided with the insertion hole and an ear portion on the inner side of the ear portion. And a step portion that is convex, and the step portion may be a contact region with the elastic body. In this case, the rigidity of the end plate can be enhanced by the stepped portion.

  The first uneven portions may be scattered in the height direction, and the second uneven portions may extend straight in the width direction without intersecting the first uneven portions. With such a configuration of the first concavo-convex portion and the second concavo-convex portion, it is possible to achieve the securing of the strength against the falling deformation and the bending deformation and the relaxation of the increase in the restraint load with respect to the expansion amount of the battery cell with a simple configuration. .

  The first uneven portion may extend in a straight line in the height direction, and the second uneven portion may extend in a straight line in the width direction so as to intersect the first uneven portion. With such a configuration of the first concavo-convex portion and the second concavo-convex portion, it is possible to achieve the securing of the strength against the falling deformation and the bending deformation and the relaxation of the increase in the restraint load with respect to the expansion amount of the battery cell with a simple configuration. .

  Moreover, the 1st uneven | corrugated | grooved part may have an extension part extended toward the insertion hole located in the other side of the one edge part in which the fixed piece was provided. One edge portion side where the fixing piece is provided is reinforced in strength against bending deformation by fixing to the outside. On the other hand, the strength opposite to the one edge is relatively low on the opposite side of the one edge. Accordingly, by providing the first uneven portion with an extending portion that faces the insertion hole located on the opposite side of the one edge where the fixed piece is provided, the strength against bending deformation is reinforced on the opposite side of the one edge. Is possible.

  Moreover, it has a pair of 2nd uneven | corrugated | grooved parts, and the 2nd uneven | corrugated | grooved part pair extends in the direction which connects the insertion holes located diagonally to the ear | edge part, and even if it cross | intersects in a step part Good. In this case, the second concavo-convex portion can be provided with a reinforcing function against the falling deformation like the first concavo-convex portion.

  Moreover, the 1st uneven | corrugated | grooved part may be provided so that the one edge part in which the fixed piece was provided may be contact | connected. By reinforcing the fulcrum of the falling deformation with the first uneven portion, the occurrence of the falling deformation can be suppressed more reliably.

  Moreover, the 2nd uneven | corrugated | grooved part may extend over the step part and the ear | edge part. In this case, since the second concavo-convex portion extends with a sufficient length in the width direction of the end plate, the strength against bending deformation can be further improved.

  Moreover, the 2nd uneven | corrugated | grooved part may be unevenly distributed in the other side of the one edge part in which the fixed piece was provided. By unevenly distributing the second concavo-convex portion on the opposite side of the one edge portion, the strength against bending deformation can be suitably reinforced.

  According to this battery module, it is possible to prevent deformation and breakage of the end plate and the restraining member during battery cell expansion without increasing the number of parts.

It is a schematic sectional drawing which shows the structure of the battery module which concerns on 1st Embodiment. It is a perspective view which shows the outer surface side of the end plate which contact | abuts an elastic body. It is a perspective view which shows the inner surface side of the end plate which contact | abuts an elastic body. It is a principal part expanded sectional view which shows the arrangement | positioning state of the elastic body and end plate at the normal time. It is a principal part expanded sectional view which shows the arrangement | positioning state of the elastic body and end plate at the time of a battery cell expansion | swelling. It is a graph which shows the relationship of the restraint load with respect to the compression amount of an elastic body about an Example and a comparative example. It is a figure which shows the structure of the end plate in the battery module which concerns on 2nd Embodiment from the outer surface side. It is a figure which shows the structure of the end plate in the battery module which concerns on 3rd Embodiment from the outer surface side. It is a figure which shows the structure of the end plate in the battery module which concerns on 4th Embodiment from the outer surface side.

Hereinafter, preferred embodiments of a battery module according to one aspect of the present invention will be described in detail with reference to the drawings.
[First Embodiment]

  FIG. 1 is a schematic cross-sectional view showing the configuration of the battery module according to the first embodiment. As shown in the figure, the battery module 1 according to the first embodiment includes an array body 2 in which a plurality of battery cells 3 are arrayed, an elastic body 4 disposed at one end of the array body 2, and an array body. 2 and a pair of end plates 5 and 6 sandwiching the elastic body 4 in the arrangement direction of the battery cells 3, and a restraining member 7 for applying a restraining load to the array body 2 and the elastic body 4 sandwiched between the pair of end plates 5 and 6. And.

  The battery cell 3 constituting the array 2 is a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery. In the present embodiment, the array body 2 is composed of 13 battery cells 3. Each battery cell 3 may be held by, for example, a resin cell holder. A heat transfer plate may be arranged with respect to the battery cell 3.

  The battery cell 3 includes an electrode assembly and an electrolyte solution in a hollow case having a substantially rectangular parallelepiped shape, for example. A pair of electrode terminals are provided apart from each other on the top surface of the case. One of the electrode terminals is a positive electrode terminal connected to the positive electrode of the electrode assembly, and the other of the electrode terminals is a negative electrode terminal connected to the negative electrode of the electrode assembly. Adjacent battery cells 3 and 3 are arranged so that the positive electrode terminal and the negative electrode terminal are adjacent to each other, and are connected in series by connecting the adjacent positive electrode terminal and the negative electrode terminal with a bus bar member. .

  The elastic body 4 is a member used for the purpose of preventing the battery cell 3, the end plates 5 and 6, and the restraining member 7 from being damaged by the restraining load when the battery cell 3 is expanded. The elastic body 4 is formed in a rectangular plate shape by a rubber sponge made of urethane, for example. Examples of other forming materials of the elastic body 4 include ethylene propylene diene rubber (EPDM), chloroprene rubber, and silicon rubber. The elastic body 4 is not limited to rubber and may be a spring material or the like.

  The end plates 5 and 6 are metal plate-shaped members, for example. As shown in FIG. 1, the end plates 5 and 6 have an area larger than the area when the battery cells 3 are viewed from the arrangement direction, for example. One end plate 5 is disposed so as to contact the elastic body 4. The other end plate 6 is disposed on the opposite side of the elastic body 4 so as to contact the battery cell 3 positioned at the array end of the array body 2. At the four corners of the end plates 5 and 6, insertion holes 15 through which shaft portions of the below-described restraint bolts 13 are inserted are respectively provided.

  On one edge portion 5a of the end plate 5, a fixing piece 8 used for fixing to the outside (here, the housing 9) is provided. The fixed piece 8 protrudes from the one edge portion 5a of the end plate 5 at a substantially right angle to the end plate 5 with a width smaller than the width of the one edge portion 5a. The fixing piece 8 is provided with a plurality (three in this case) of insertion holes 11 through which the fixing bolts 10 are inserted at predetermined intervals in the width direction of the end plate 5. A similar fixing piece 8 is also provided at one edge 6 a of the end plate 6. The battery module 1 is firmly fixed to the housing 9 by screwing the fixing bolts 10 passed through these insertion holes 11 into the bolt holes 12 provided in the housing 9.

  In this embodiment, the restraining member 7 is composed of restraining bolts 13 and nuts 14. For example, the restraint bolt 13 is passed through the insertion hole 15 from the other end plate 6 side toward the one end plate 5 side. A nut 14 is screwed into a tip portion of the restraint bolt 13 protruding from one end plate 5. Accordingly, the battery cell 3 and the elastic body 4 are sandwiched and unitized, and a predetermined restraining load is applied to the battery cell 3 and the elastic body 4 via the end plates 5 and 6 by the fastening force of the nut 14. .

  Next, the configuration of the end plate 5 that contacts the elastic body 4 will be described in more detail.

  FIG. 2 is a perspective view showing the outer surface side of the end plate 5. FIG. 3 is a perspective view showing the inner surface side. In the following description, for convenience, a direction connecting the one edge portion 5a where the fixing piece 8 is provided and the other edge portion 5b opposite to the one edge portion 5a is referred to as a height direction. In addition, a direction orthogonal to the height direction in the front view of the end plate 5 is referred to as a width direction. Further, the surface in the direction in which the fixed piece 8 protrudes is the outer surface side, and the surface in contact with the elastic body 4 is the inner surface side.

  As shown in FIGS. 2 and 3, the end plate 5 includes a stepped portion 21, an ear portion 22, a first uneven portion 23, and a second uneven portion 24. The stepped portion 21 is an uneven portion that is integrated with the front and back sides, for example, formed by press molding. As shown in FIG. 2, the stepped portion 21 is a concave portion 21 a on the outer surface side of the end plate 5 and a convex portion 21 b on the inner surface side. The step portion 21 is provided in a rectangular shape in a region inside the ear portion 22 so as to correspond to the contact region with the elastic body 4, and is convex with respect to the ear portion 22. In the present embodiment, the height of the stepped portion 21 is slightly lower than the height of the end plate 5, and the width of the stepped portion 21 is smaller than the width of the end plate 5 and is substantially equal to the lateral width of the fixed piece 8. Are equal.

  Since the width of the stepped portion 21 is smaller than the width of the end plate 5, each of the one side and the other side in the width direction of the end plate 5 is a flat portion having a width about twice the inner diameter of the insertion hole 15, for example. These are the ears 22 of the end plate 5. The insertion holes 15 provided at the four corners of the end plate 5 are all provided in the ear portion 22. The positions of the insertion holes 15 are the four corners of the end plate 5 in the present embodiment, but may be provided at other positions of the edge of the end plate 5.

  The first concavo-convex part 23 and the second concavo-convex part 24 are front and back integral concavo-convex parts formed by press molding, for example, like the stepped part 21. As shown in FIG. 2, the first concavo-convex portion 23 is a convex portion (first convex portion) 23a on the outer surface side of the end plate 5, and as shown in FIG. It has become. Similarly, as shown in FIG. 2, the second concavo-convex portion 24 is also a convex portion (second convex portion) 24a on the outer surface side of the end plate 5, and as shown in FIG. It is a recess 24b.

  The first uneven portion 23 extends in the height direction of the end plate 5 with the one edge portion 5a as a base portion. In the present embodiment, the first concavo-convex portion 23 includes a first concavo-convex portion 23A in contact with the one edge portion 5a provided with the fixed piece 8, and a first concavo-convex portion 23B provided near the center in the height direction. And are scattered in the height direction without intersecting the second uneven portion 24. 23 A of 1st uneven parts and the 1st uneven part 23B have comprised the substantially rectangular shape which makes a height direction a long side in the front view of the end plate 5. As shown in FIG. The first uneven portion 23 </ b> A and the second uneven portion 24 </ b> B are provided in two rows at positions between the insertion holes 11 and 11 formed in the fixed piece 8.

  The second uneven portion 24 extends in the width direction of the end plate 5. In the present embodiment, the second uneven portion 24 is a second portion extending in a straight line from the step portion 21 to the ear portions 22 and 22 on both sides at a position between the first uneven portion 23A and the first uneven portion 23B. 24A and the second uneven portion 24B extending in a straight line from the step portion 21 to the ear portions 22 and 22 on both sides at a position closer to the other edge portion 5b than the first uneven portion 23B. Yes. Further, the second uneven portion 24A and the second uneven portion 24B are unevenly distributed on the opposite side of the one edge portion 5a where the fixed piece 8 is provided, that is, on the other edge portion 5b side. In the present embodiment, the interval between the second uneven portion 24B and the other edge portion 5b is the interval between the second uneven portion 24A and the second uneven portion 24B, and the second uneven portion 24B and the one edge portion 5a. It is smaller than the interval.

  Then, the effect of the battery module 1 mentioned above is demonstrated.

  In a normal state, the battery module 1 is in a state where the inner surface side of the end plate 5 is in contact with the elastic body 4 as shown in FIG. On the outer surface side of the end plate 5, the convex portion 23 a of the first uneven portion 23 and the convex portion 24 a of the second uneven portion 24 function as ribs of the end plate 5, respectively. Further, on the inner surface side of the end plate 5, the convex portion 21 b of the stepped portion 21 abuts on the elastic body 4, and between the formation position of the first uneven portion 23 and the second uneven portion 24 and the surface of the elastic body 4. A space is formed by the recesses 23b and 24b.

  When the battery cell 3 expands due to deterioration or the like, the restraining load applied to the battery cell 3 increases. At this time, as shown in FIG. 5, the elastic body 4 is compressed in the thickness direction as the battery cell 3 expands, and the amount of increase in the restraint load relative to the expansion amount of the battery cell 3 is alleviated. In addition, when the battery cell 3 is expanded, the end plate 5 has an indentation deformation that falls outward with the one edge portion 5a provided with the fixing piece 8 as a fulcrum, and a convex shape outward in the width direction. Curved deformation can occur.

  On the other hand, in the battery module 1, the strength against the indentation deformation is ensured by the convex portion 23a of the first uneven portion 23 provided in the height direction on the outer surface side of the end plate 5, and the first provided in the width direction. The strength against bending deformation is ensured by the convex portions 24 a of the two concave-convex portions 24. According to this configuration, since a reinforcing member other than the end plate 5 is not used, it is possible to prevent the end plate 5 from being deformed when the battery cell is expanded without increasing the number of components.

  In the battery module 1, the concave portion 23 b of the first concave and convex portion 23 and the concave portion 24 b of the second concave and convex portion 24 are provided in the contact area with the elastic body 4 on the inner surface side of the end plate 5. When the compression of the elastic body 4 proceeds along with the expansion of the battery cell, the elastic body 4 enters the space defined by the recesses 23b and the recesses 24b as shown in FIG.

  When a flat end plate that does not allow the elastic body 4 to escape is used, as shown in FIG. 6, the amount of increase in the restraint load relative to the compression amount of the elastic body 4 is substantially equal to the physical property of the elastic body 4. It is gradual until the amount exceeds the compression margin, but increases rapidly when the compression amount exceeds the compression margin (Comparative Example: Graph A). On the other hand, when the end plate 5 provided with a clearance for the elastic body 4 is used, the amount of increase in the restraint load relative to the compression amount of the elastic body 4 is reduced compared to the comparative example even when the compression amount exceeds the compression margin. (Example: Graph B).

  As described above, in the battery module 1, the first uneven portion 23 and the second uneven portion 24 sufficiently increase the strength of the end plate 5 itself against the indentation deformation and the bending deformation, and the battery cell 3 expands. The amount of increase in the restraint load with respect to the amount is reduced. Therefore, it is possible to prevent deformation and breakage of the end plate 5 and the restraining member 7 when the battery cell is expanded without increasing the number of parts.

  Further, in the battery module 1, insertion holes 15 through which the restraint bolts 13 are inserted are provided at the four corners of the end plate 5, and the contact area of the end plate 5 with the elastic body 4 is a stepped portion 21 with respect to the ear portion 22. ing. According to such a configuration, the rigidity of the end plate 5 can be enhanced by the step portion 21. Further, by separating the step portion 21 and the ear portion 22, for example, it is possible to ensure the ease of arrangement of a tool used when the nut 14 is screwed to the restraint bolt 13, and the seat surface of the nut 14 is another portion. Can be prevented from interfering with.

  Further, in the battery module 1, the first uneven portions 23 are scattered in the height direction of the end plate 5, and the second uneven portions 24 do not intersect the first uneven portion 23 and the end plate 5 It extends in a straight line in the width direction. With such a configuration of the first concavo-convex portion 23 and the second concavo-convex portion 24, it is possible to simply secure the strength against the indentation deformation and the bending deformation and to relax the increase in the restraint load with respect to the expansion amount of the battery cell 3. Can be realized.

  In the battery module 1, the first uneven portion 23 </ b> A is provided on the end plate 5 so as to be in contact with the one edge portion 5 a on which the fixing piece 8 is provided. The one edge portion 5a provided with the fixed piece is a portion serving as a fulcrum for the falling deformation. Therefore, by reinforcing the fulcrum of the falling deformation with the first uneven portion 23A, the occurrence of the falling deformation can be more reliably suppressed.

  In the battery module 1, the second uneven portion 24 extends over the step portion 21 and the ear portion 22 in the end plate 5. Thereby, since the 2nd uneven | corrugated | grooved part 24 is extended in the width direction of the end plate 5 with sufficient length, the further improvement of the intensity | strength with respect to a curved deformation is achieved.

Moreover, in the battery module 1, the 2nd uneven | corrugated | grooved part 24 is unevenly distributed by the other edge part 5b side which is the other side of the one edge part 5a in which the fixed piece 8 was provided. The one edge portion 5 a side where the fixing piece 8 is provided is reinforced by the fixing bolt 10 to the external housing 9 to reinforce the strength against bending deformation. On the other hand, in the other edge part 5b which is the other side of the one edge part 5a, the intensity | strength with respect to a curved deformation becomes comparatively low compared with the one edge part 5a. Therefore, the intensity | strength with respect to curve deformation | transformation can be reinforced suitably by making the 2nd uneven | corrugated | grooved part 24 unevenly distributed to the other edge part 5b side.
[Second Embodiment]

  FIG. 7 is a view showing the configuration of the end plate in the battery module according to the second embodiment from the outer surface side. As shown in the figure, the battery module according to the second embodiment is different from the first embodiment in the configuration of the first uneven portion 33 and the second uneven portion 34 in the end plate 5.

More specifically, in this embodiment, the 1st uneven | corrugated | grooved part 33 is provided in 2 rows in the position between the insertion holes 11 and 11 formed in the fixed piece 8, and is extended in the straight line shape in the height direction. Yes. For example, the tip of the first uneven portion 33 extends to the same height as the insertion holes 15 and 15 on the other edge portion 5b side. The second concavo-convex part 34 intersects the first concavo-convex part 33 and extends in a straight line in the width direction. The 2nd uneven | corrugated | grooved part 34 is extended over the ear | edge parts 22 and 22 of the both sides from the step part 21 similarly to 1st Embodiment. Even in such a configuration, it is possible to achieve the securing of the strength against the indentation deformation and the bending deformation and the relaxation of the increase in the restraint load with respect to the expansion amount of the battery cell 3 with a simple configuration.
[Third Embodiment]

  FIG. 8 is a view showing the configuration of the end plate in the battery module according to the third embodiment from the outer surface side. As shown in the figure, the battery module according to the third embodiment is further different from the second embodiment in the configuration of the first uneven portion 43 in the end plate 5. The structure of the 2nd uneven | corrugated | grooved part 44 is the same as 1st Embodiment and 2nd Embodiment.

  More specifically, in this embodiment, the 1st uneven | corrugated | grooved part 43 has the extension part 43a extended toward the insertion hole 15 located in the other edge part 5b side. In FIG. 8, the first uneven portion 43 located on the right side is linear along the height direction from the one edge portion 5a to the position intersecting with the second uneven portion 44 on the other edge portion 5b side. The tip end side of the second concavo-convex portion 44 extends obliquely to the ear portion 22 toward the right insertion hole 15 from the position intersecting the second concavo-convex portion 44. In addition, the first uneven portion 43 located on the left side is linear along the height direction from the one edge portion 5a to the position intersecting the second uneven portion 24 on the other edge portion 5b side, The tip side from the position intersecting with the second uneven portion 44 extends obliquely to the ear portion 22 toward the left insertion hole 15.

Even in such a configuration, it is possible to achieve the securing of the strength against the indentation deformation and the bending deformation and the relaxation of the increase in the restraint load with respect to the expansion amount of the battery cell 3 with a simple configuration. In addition, by providing the first uneven portion 43 with the extending portion 43a toward the insertion hole 15, the first uneven portion 43 can be provided with a reinforcing function against bending deformation. By providing the extended portion 43a of the first concavo-convex portion 43 on the side of the other edge portion 5b, which has a relatively low strength against bending deformation compared to the one edge portion 5a, the strength against bending deformation can be suitably improved.
[Fourth Embodiment]

  FIG. 9 is a diagram showing the configuration of the end plate in the battery module according to the fourth embodiment from the outer surface side. As shown in the figure, the battery module according to the fourth embodiment is further different from the first embodiment in the configuration of the first uneven portion 53 and the second uneven portion 54 in the end plate 5.

  More specifically, in this embodiment, the 1st uneven | corrugated | grooved part 53 is comprised only by the part which contact | connects the one edge part 5a. The first uneven portion 53 extends from the one edge portion 5a to a height at which the first uneven portion 53 does not contact the second uneven portion 54. On the other hand, the second concavo-convex portion 54 extends in a direction connecting the insertion holes 15, 15 diagonally located on the ear portion 22, and intersects with each other at the approximate center of the stepped portion 21. It is configured by 54B pairs.

  According to such a configuration, the pair of the second concavo-convex portions 54A and 54B is diagonally arranged, so that the second concavo-convex portion 54 can be prevented from falling down like the first concavo-convex portion 23. A reinforcing function can be provided. Therefore, it is possible to secure the strength against the falling deformation and the bending deformation and to relax the increase in the restraining load with respect to the expansion amount of the battery cell 3 with a simple configuration.

  The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the first uneven portion and the second uneven portion in which the unevenness is integrated on the front and back sides are illustrated, but the position of the concave portion on the inner surface side in the end plate 5 necessarily coincides with the position of the convex portion on the outer surface side. It does not have to be. One or a plurality of recesses may be provided at an arbitrary position in the contact area of the end plate 5 with the elastic body 4.

  In addition, about the end plate 6 arrange | positioned on the opposite side of the elastic body 4, the thing of the structure similar to the end plate 5 contact | abutted to the elastic body 4 may be used, and even if it is a flat thing without unevenness Good.

  DESCRIPTION OF SYMBOLS 1 ... Battery module, 2 ... Array, 3 ... Battery cell, 4 ... Elastic body, 5, 6 ... End plate, 5a ... One edge part, 7 ... Restraint member, 8 ... Fixed piece, 13 ... Restraint bolt, 15 ... Insertion hole, 21 ... Step part, 22 ... Ear part, 23 (24A, 24B), 33, 43, 53 ... First uneven part, 24 (24A, 24B), 34, 44, 54 (54A, 54B) ... 2nd uneven | corrugated | grooved part, 23a ... convex part (1st convex part), 24a ... convex part (2nd convex part), 23b, 24b ... recessed part, 43a ... extended part.

Claims (10)

An array formed by arranging a plurality of battery cells;
An elastic body disposed at one end of the array;
A pair of end plates that sandwich the array and the elastic body in the array direction of the battery cells;
A restraining member that applies a restraining load to the array and the elastic body sandwiched between the pair of end plates;
One edge of the pair of end plates is provided with a fixing piece used for fixing to the outside,
On the outer surface side of the end plate in contact with the elastic body, a first convex portion extending in the height direction with the one edge portion as a base, and a second convex portion extending in the width direction intersecting the height direction, Is provided,
A battery module, wherein one or a plurality of recesses are provided on an inner surface side of the end plate in contact with the elastic body, corresponding to a contact area with the elastic body.   The 1st uneven part in which said 1st convex part and said crevice were united front and back, and the said 2nd convex part and said crevice have the 2nd uneven part by which front and back were integrated. Item 1. The battery module according to Item 1. An insertion hole for inserting a restraining bolt constituting the restraining member is provided at an edge of the end plate,
The end plate has an ear portion provided with the insertion hole, and a step portion that is convex with respect to the ear portion inside the ear portion,
The battery module according to claim 2, wherein the step portion is a contact area with the elastic body. The first uneven portions are scattered in the height direction,
The battery module according to claim 3, wherein the second uneven portion extends straight in the width direction without intersecting with the first uneven portion. The first uneven portion extends in a straight line in the height direction,
The battery module according to claim 3, wherein the second uneven portion extends in a straight line in the width direction so as to intersect the first uneven portion.   The battery module according to claim 5, wherein the first uneven portion has an extending portion that extends toward the insertion hole located on the opposite side of the one edge portion on which the fixing piece is provided. . Having a pair of said second irregularities;
4. The battery module according to claim 3, wherein the pair of second concavo-convex parts extends in a direction connecting the insertion holes located diagonally to the ear part, and intersects each other at the stepped part.   The battery module according to claim 4, wherein the first uneven portion is provided so as to be in contact with the one edge portion on which the fixing piece is provided.   The battery module according to any one of claims 4 to 7, wherein the second concavo-convex portion extends across the stepped portion and the ear portion.   The battery module according to any one of claims 4 to 9, wherein the second uneven portion is unevenly distributed on the opposite side of the one edge portion on which the fixing piece is provided.

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