JP6740722B2 - Battery pack and battery module - Google Patents

Description

The present invention relates to a battery pack and a battery module.

A battery pack is known in which a battery module in which battery cells are arranged is attached to a housing or the like. For example, in Patent Document 1, a battery module having an array body in which battery cells are arrayed, a pair of end plates arranged at both ends in the array direction of the array body, and a plurality of fastening members for fastening the end plates together. Describes a battery pack in which is housed in a housing. In such a battery pack, the battery module is fixed to the wall surface of the housing by a fixing member such as an end plate.

JP, 2005-023003, A

When the battery cell expands as the deterioration of the battery cell progresses, the array end of the array body presses the fixing member, and the fixing member is deformed in the array direction (first direction). At this time, in the fixing member, the bending stress (bending moment) increases as the distance from the portion fastened by the fastening member (fastening portion) increases. Therefore, the deformation of the fixing member in the first direction is unlikely to occur at the fastening portion and is likely to occur at a portion away from the fastening portion.

For example, when the fixing member has a flat plate-shaped main body and the main body is fastened by a plurality of fastening members at a plurality of fastening portions, a bending stress that bends the main body portion in the first direction with the fastening portion as a fixed end. Acts on the body. As a result, the portion of the main body portion sandwiched by the fastening portions is deformed so as to bulge in the first direction. Due to such deformation of the main body, stress concentration may occur in the fastening member at the fastening portion, and the durability of the fastening member may be reduced.

Therefore, an object of the present invention is to provide a battery pack and a battery module that can reduce stress concentration in the fastening member due to deformation of the fixing member.

A battery pack of the present invention is a battery pack in which a battery module is housed in a housing, and the battery module includes an array body including a plurality of battery cells arrayed along a first direction and an array body. A pair of fixing members each having a flat plate-shaped main body portion sandwiched in one direction and a fixing portion fixed to a wall surface of the housing, and the main body portions are fastened together and the first direction with respect to the array body. A plurality of fastening members that apply a restraining load to the main body, and a reinforcing portion that improves rigidity against bending stress acting on the main body portion such that the main body portion is bent in the first direction with the fastening portion formed by the fastening members as a fixed end. , Is formed on at least one main surface intersecting the first direction.

In the battery pack having this configuration, the reinforcing portion improves the rigidity against bending stress acting on the main body portion such that the main body portion is bent in the first direction with the fastening portion as the fixed end. Therefore, the portion sandwiched by the fastening portions is the first portion. Bending deformation of the main body that bulges in the direction is suppressed. Bending of the fastening member due to deformation of the main body is suppressed. Therefore, it is possible to reduce the occurrence of stress concentration on the fastening member due to the deformation of the fixing member.

In the battery pack of the present invention, the reinforcing portion may be formed on the side farther from the housing than the central portion of the main body portion. In this case, the bending rigidity can be surely improved on the side farther from the housing than the central portion of the main body.

In the battery pack of the present invention, the main body portion includes a pair of fastening portions fastened by fastening members at both ends in the second direction intersecting the first direction, and the reinforcing portion is sandwiched by the pair of fastening portions of the main body portion. May be formed in at least the region to be formed. In this case, since the bending rigidity of the portion of the main body portion that is sandwiched by the pair of fastening portions is improved, it is possible to suppress deformation of the fixing member that bulges outward in the first direction.

As a configuration that preferably achieves the above-described effects, specifically, the second direction may be a direction substantially parallel to the wall surface.

In the battery pack of the present invention, the reinforcing portion may include a rib protruding from the main surface and extending along the second direction. In this case, the ribs extending along the second direction can effectively improve the bending rigidity of the main body.

In the battery pack of the present invention, the reinforcing portion may have higher rigidity with respect to bending stress in the direction intersecting the wall surface as the distance from the housing increases. In this case, since the rigidity with respect to bending stress increases as the distance from the housing increases, it is possible to preferably suppress the bending deformation of the main body portion in the portion away from the housing.

In the battery pack of the present invention, the reinforcing portion is such that the thickness of the main body portion on the side farther from the housing than the central portion of the main body portion is greater than the thickness of the main body portion on the side closer to the housing than the central portion of the main body portion. It may be a thick portion. In this case, the reinforcing portion can be easily formed.

As a configuration that preferably achieves the above-described operational effects, specifically, the reinforcing portion may be a plate member provided on the main surface along the main body portion.

In the battery pack of the present invention, the reinforcing portion may have an insertion hole through which the plurality of fastening members are inserted. In this case, by inserting the fastening member through the insertion hole of the reinforcing portion, it is possible to perform joint fastening in which the reinforcing portion and the main body portion are fastened with a common fastening member.

In the battery pack of the present invention, the fixed portion includes a plate-shaped member extending in a predetermined dimension along the wall surface, and the dimension along the wall surface of the main body portion including the reinforcing portion is larger than the predetermined dimension of the fixed portion. It may be small. In this case, since the main body portion and the reinforcing portion can be provided within the range of the dimension along the wall surface of the fixed portion, the reinforcing portion does not protrude beyond the fixed portion in the direction along the wall surface. As a result, the space inside the housing can be effectively used.

In the battery pack of the present invention, the main surface may be the surface of the main body on the side of the array body. In this case, the space on the array side in the main body can be used.

In the battery pack of the present invention, the battery module further has an elastic member arranged at one of the arrangement ends of the arrangement body, and the reinforcing portion is formed of the fixing member on the side where the elastic member is arranged among the pair of fixing members. It may be provided in the main body. In this case, by increasing the bending rigidity of the main body of the fixing member on the side where the elastic member is arranged, it is possible to preferably suppress the bending deformation of the main body.

Further, the battery module of the present invention is a pair of fixed members having an array body including a plurality of battery cells arrayed along the first direction, and a flat plate-shaped main body section sandwiching the array body in the first direction. A member and a plurality of fastening members that fasten the body portions to each other and apply a restraining load to the array body in the first direction. The fastening portion formed by the fastening members serves as a fixed end to move the body portion in the first direction. A reinforcing portion that improves rigidity against bending stress acting on the main body portion so as to bend is formed on at least one main surface intersecting the first direction.

In the battery module having this configuration, the reinforcing portion improves the rigidity against bending stress acting on the main body portion such that the main body portion is bent in the first direction with the fastening portion as the fixed end, so that the portion sandwiched between the fastening portions is the first portion. Bending deformation of the main body that bulges in the direction is suppressed. Bending of the fastening member due to deformation of the main body is suppressed. Therefore, it is possible to reduce the occurrence of stress concentration on the fastening member due to the deformation of the fixing member.

According to the present invention, it is possible to provide a battery pack and a battery module that can reduce stress concentration on the fastening member due to deformation of the fixing member.

FIG. 1 is a schematic side view of the battery pack according to the present embodiment. FIG. 2 is a diagram showing an example of bending deformation of the main body portion of FIG. FIG. 3 is a partially exploded perspective view of the battery module of FIG. FIG. 4 is a partially exploded perspective view of the battery module of FIG. FIG. 5 is a perspective view of the fixing member of FIG. FIG. 6 is a perspective view of a first modification of the fixing member. FIG. 7 is a perspective view of a second modification of the fixing member. FIG. 8 is a perspective view of the fixing member of FIG. 7 viewed from another direction. FIG. 9 is a diagram illustrating an elastic member used for the fixing member of FIG. 7. FIG. 10 is a perspective view of a third modification of the fixing member.

Hereinafter, a battery pack 100 and a battery module 2 according to an embodiment of the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements or corresponding elements may be denoted by the same reference symbols, and redundant description may be omitted. In the following description, the orthogonal coordinate system S attached to the drawings may be used.

As shown in FIG. 1, the battery pack 100 according to the present embodiment includes a housing 1, a battery module 2, and a heat conduction member (TIM: Thermal Interface Material) T. The housing 1 has a wall surface 1s. The battery module 2 is housed in the housing 1 of the battery pack 100. The battery module 2 is fixed to the wall surface 1s of the housing 1. A heat conducting member T is arranged between the battery module 2 and the wall surface 1s.

As shown in FIGS. 1 and 2, the battery module 2 includes an array body 2a including a plurality of battery cells 11 arranged along an array direction A (first direction) and an array end of the array body 2a. It has a pair of fixed members 3 and 3 arranged, and a plurality of fastening members 4 which fasten main part 30 comrades and apply a restraining load to array 2a in array direction A. The number of battery cells 11 is seven as an example. The arrangement direction A is not particularly limited, but in the example of FIG. 1, it is the X direction indicated by the orthogonal coordinate system S. In the present embodiment, the main body portion 30 of the fixing member 3 is not deformed in the arrangement direction A before the deterioration of the battery cells 11 progresses. When the battery cell 11 expands as the deterioration of the battery cell 11 progresses, one end (arrangement end) 2b of the array body 2a presses the main body section 30 and the main body section 30 is deformed in the array direction A ( See below for details).

As shown in FIG. 2, the battery cell 11 is electrically connected to an electrode assembly 12, a case 13 that houses the electrode assembly 12, and electrodes (a positive electrode and a negative electrode) of the electrode assembly 12. It has a pair of terminals 14, 14. The electrode assembly 12 includes a plurality of positive electrodes (not shown) and negative electrodes (not shown), and a separator (not shown) disposed between the positive electrodes and the negative electrodes. The positive electrodes and the negative electrodes are arranged alternately along the arrangement direction A with the separators in between.

The case 13 has a rectangular parallelepiped shape. The case 13 includes a pair of side surfaces 13a and 13b facing each other, a pair of side surfaces 13c and 13d facing each other, and a top surface 13e and a bottom surface 13f facing each other. The side surfaces 13a and 13b are surfaces along the arrangement direction A. The side surfaces 13c and 13d are surfaces that intersect in the arrangement direction A. The side surfaces 13a and 13b connect the side surface 13c and the side surface 13d to each other. The terminal 14 projects from the upper surface 13e.

The battery cell 11 is held by the cell holder 20. The cell holder 20 includes a side wall portion 20c and a side wall portion 20d facing each other, a back surface portion 20e and a bottom wall portion 20f. The side wall portions 20c and 20d have a rectangular plate shape. The back surface portion 20e has a rectangular plate shape, and connects the side wall portion 20c and the side wall portion 20d to each other at one longitudinal end portion of the side wall portions 20c and 20d. The bottom wall 20f has a rectangular plate shape, and connects the side wall 20c and the side wall 20d to each other at the other longitudinal ends of the side walls 20c and 20d.

In the cell holder 20, the side wall portions 20c and 20d, the back surface portion 20e, and the bottom wall portion 20f define a rectangular parallelepiped space portion into which the battery cell 11 is fitted. The side wall portions 20c and 20d are arranged on the side surfaces 13c and 13d of the case 13 when the battery cell 11 is fitted in the space portion. Similarly, the rear surface portion 20e is arranged on the upper surface 13e of the case 13. Further, the bottom wall portion 20f is arranged on the bottom surface 13f of the case 13.

The rear surface portion 20e is provided with a pair of protruding portions 21 and 21. The protruding portion 21 has a rectangular parallelepiped shape. The protruding portion 21 extends along the arrangement direction A. The protruding portion 21 is arranged on the upper surface 13e of the case 13 at a position between the pair of terminals 14 and 14 when the battery cell 11 is fitted in the space. A through hole 21h is formed in the protruding portion 21 along the extending direction thereof. Bolts 40 and 41 of the fastening member 4 described later are inserted into the through holes 21h.

Further, a pair of projecting portions 22 and 22 is provided at the connection portion of the bottom wall portion 20f with the side wall portions 20c and 20d. The protruding portion 22 has a rectangular parallelepiped shape. The protruding portion 22 extends along the arrangement direction A. When the battery cell 11 is fitted in the space, the protruding portion 22 is arranged at the end of the bottom surface 13f of the case 13 on the side surface 13c, 13d side. A through hole 22h is formed in the protruding portion 22 along the extending direction thereof. Bolts 42 and 43 of the fastening member 4 described later are inserted into the through holes 22h.

The heat transfer plate 15 includes a rectangular plate-shaped main body portion 15a and a rectangular plate-shaped extending portion 15c. The heat transfer plate 15 is formed in an L-shaped plate shape by the main body portion 15a and the extending portion 15c. The main body portion 15a is arranged on the side surface 13a of the battery cell 11 (case 13). The extending portion 15c extends from the main body portion 15a along the arrangement direction A and is arranged on the side surface 13c of the battery cell 11 (case 13). The extending portion 15c is arranged on the side surface 13c via the side wall portion 20c of the cell holder 20.

The heat transfer plate 15 contacts the battery cell 11 in the main body portion 15a, and also contacts the heat conducting member T on the surface of the extending portion 15c opposite to the side wall portion 20c. That is, the heat transfer plate 15 thermally connects the battery cell 11 and the housing 1 via the heat conducting member T. In the present embodiment, the heat transfer plate 15 is attached to the battery cell 11 so that the fixing portion 35 of the fixing member 3 and the extending portion 15c of the battery module 2 are located on the same side with respect to the battery cell 11. That is, the heat of the battery cells 11 is radiated to the wall surface 1s of the housing 1 via the extending portion 15c.

The fixing member 3 is a member for fixing the battery module 2 to the wall surface 1s of the housing 1. The fixing member 3 has, for example, an L-shaped plate-shaped outer shape as a whole. As shown in FIGS. 3 and 4, the fixing member 3 includes a rectangular flat plate-shaped main body portion 30 arranged with the array body 2a sandwiched in the arraying direction A, and an end portion of the main body portion 30 on the housing 1 side. A fixing portion 35 extending along the arrangement direction A.

The body portion 30 extends along a direction B (second direction) that intersects the arrangement direction A. The main body portion 30 includes, for example, a rectangular main body base portion 30BS extending along the YZ plane. The main body base portion 30BS is a portion of the main body portion 30 that extends in a flat plate shape with a thickness TH1 and is a portion that serves as a base of a rib 30r and a reinforcing portion 32 described later. The direction B here is a direction along the Z direction, and is a direction substantially parallel to the wall surface 1s.

The fixing portion 35 has a length L along the arrangement direction A from the end of the main body portion 30 on the side of the housing 1 toward the side opposite to the arrangement body 2a (with a predetermined dimension along the wall surface 1s. ) A rectangular flat plate-shaped member that extends. The fixing portion 35 is fixed to the wall surface 1s by the bolt 6 while being in contact with the wall surface 1s. Thereby, the battery module 2 is fixed to the wall surface 1s of the housing 1.

The main body base portion 30BS includes protruding portions 31a and 31b provided on one outer edge 30a of the main body base portion 30BS and protruding portions 31c and 31d provided on an outer edge 30b on the opposite side of the outer edge 30a of the main body base portion 30BS. Including.

The protruding portions 31a and 31b have a rectangular plate shape with a thickness TH1. The projecting portions 31 a and 31 b project from the upper surface 13 e of the battery cell 11 on the upper surface 13 e side of the battery cell 11 when viewed in the arrangement direction A. A through hole H is provided in each of the protruding portions 31a and 31b. The through hole H overlaps with the through hole 21h of the protruding portion 21 of the cell holder 20 when viewed from the arrangement direction A. Bolts 40 and 41 of the fastening member 4 described later are inserted into the through holes H.

The protruding portions 31c and 31d have a rectangular plate shape with a thickness TH1. The protruding portions 31c and 31d project from the upper surface 13e of the battery cell 11 on the bottom surface 13f side of the battery cell 11 when viewed in the arrangement direction A. A through hole H is provided in each of the protruding portions 31c and 31d. The through hole H overlaps with the through hole 22h of the projecting portion 22 of the cell holder 20 when viewed from the arrangement direction A. Bolts 42 and 43 of the fastening member 4 described later are inserted into the through holes H.

The fastening member 4 applies a restraining load to the plurality of battery cells 11 (array 2a) along the array direction A by fastening the pair of fixing members 3 and 3 to each other. The battery module 2 includes a plurality (four here) of fastening members 4. The fastening member 4 includes, for example, long bolts 40 to 43 and a nut 5 screwed into each of the bolts 40 to 43. As an example, the bolts 40 to 43 have a hexagonal columnar head portion 4b integrally formed at one end 4a and a screw thread at the other end 4c. The nut 5 is screwed into the other end 4c of the bolts 40 to 43. The bolts 40 and 41 of the fastening member 4 apply a restraining load in the arrangement direction A of the battery cells 11 to the array 2a at the end B1 of the main body portion 30 in the direction B. The bolts 42 and 43 of the fastening member 4 apply a restraining load in the arrangement direction A of the battery cells 11 to the array 2a at the end B2 of the main body portion 30 in the direction B.

A plurality of ribs 30r projecting from the outer surface 30s are formed on an outer surface (main surface) 30s of the main body base 30BS that intersects the arrangement direction A. One end side of the rib 30r is continuous with the fixed portion 35 on the surface 35s of the fixed portion 35. The protruding height of the rib 30r on one end side is substantially equal to the length L of the fixing portion 35 along the arrangement direction A. The other end of the rib 30r reaches the central portion M of the body portion 30. The rib 30r extends along the Y direction from one end side to the other end side. The protruding height of the rib 30r gradually decreases from one end side to the other end side, and is substantially constant in a certain range on the other end side. The rib 30r mainly has a function of suppressing the deformation of the main body portion 30 so as to incline with respect to the fixed portion 35, with the location where the main body portion 30 and the fixed portion 35 intersect as a fulcrum.

The middle plate 7 is arranged between the fixing member 3 on the one end 2b side of the array 2a and the battery cell 11 adjacent to the fixing member 3. A part of the middle plate 7 has substantially the same shape as the fixing member 3 when viewed from the arrangement direction A. Therefore, the middle plate 7 is also provided with a through hole that overlaps with the through hole H in the fixing member 3 when viewed in the arrangement direction A. An elastic member 8 that is compressed according to the expansion of the battery cell 11 is interposed between the middle plate 7 and the fixing member 3. In the present embodiment, the elastic member 8 is arranged at one end 2b which is one of the arrangement ends of the array 2a.

In the battery module 2 having such a configuration, as shown in FIG. 1, in the state in which the plurality of battery cells 11 are sandwiched along the arrangement direction A, the pair of main body portions 30, 30 30 are fastened together. As a result, a restraining load is applied to the battery cells 11 and the battery cells 11 are restrained to each other.

Next, the reinforcing portion 32 formed on the main body portion 30 of the fixing member 3 will be described with reference to FIG. The reinforcing portion 32 is included in the main body portion 30, and is a reinforcement for improving rigidity against bending stress acting on the main body portion 30 so that the main body portion 30 is bent in the arrangement direction A with the fastening portion 31 by the fastening member 4 as a fixed end. It is a part. The reinforcing portion 32 is provided, for example, in the main body portion 30 of the fixing member 3 of the pair of fixing members 3 and 3 on the one end 2b side of the array 2a (on the side where the elastic member 8 is arranged).

The reinforcing portion 32 is formed on the side farther from the housing 1 than the central portion M of the body portion 30 (the tip side of the body portion 30). The reinforcing portion 32 is, for example, a thick portion formed on the front end side of the main body portion 30. However, the reinforcing portion 32 may be a separate body from the main body base portion 30BS, or is formed integrally with the main body base portion 30BS by making the main body base portion 30BS itself thick on the outer surface 30s side of the main body portion 30. May be.

In the present embodiment, the reinforcing portion 32 is a separate member from the main body base portion 30BS, and is the plate member 33 provided on the outer surface 30s along the main body portion 30 at the tip end side of the main body portion 30. The plate member 33 has a rectangular flat plate shape and has a shape similar to the shape of the main body base portion 30BS on the tip end side of the main body portion 30. The thickness TH3 of the plate member 33 is substantially equal to the thickness TH1 of the main body base 30BS, for example. In this case, the thickness TH2 of the main body portion 30 in the reinforcing portion 32 is a thickness obtained by adding the thickness TH1 of the main body base portion 30BS and the thickness TH3 of the plate member 33. That is, in the reinforcing portion 32, the thickness TH2 of the main body portion 30 is larger than the thickness TH1 of the main body portion 30 on the side closer to the housing 1 than the central portion M of the main body portion 30 (base end side of the main body portion 30). The thickness TH2 of the body portion 30 (that is, the dimension along the wall surface 1s of the body portion 30 including the reinforcing portion 32) is smaller than the length L of the fixing portion 35 along the arrangement direction A.

The plate member 33 includes a projecting portion 32b provided so as to overlap the projecting portion 31b of the main body base 30BS, and a projecting portion 32d provided so as to overlap the projecting portion 31d of the main body base 30BS. The reinforcing portion 32 has a through hole (insertion hole) H through which the plurality of fastening members 4 are inserted.

The protruding portion 32b has a rectangular plate shape. The protruding portion 32b protrudes from the upper surface 13e of the battery cell 11 on the upper surface 13e side of the battery cell 11 when viewed in the arrangement direction A. A through hole H is provided in the protruding portion 32b. The through hole H of the projecting portion 32b penetrates through the through hole 21h of the projecting portion 21 of the cell holder 20 located on the side surface 13c side of the battery cell 11 and the projecting portion 31b of the main body base 30BS when viewed from the arrangement direction A. Overlaps with hole H.

The protruding portion 32d has a rectangular plate shape. The protruding portion 32d protrudes from the upper surface 13e of the battery cell 11 on the upper surface 13e side of the battery cell 11 when viewed in the arrangement direction A. A through hole H is provided in the protruding portion 32b. The through hole H of the projecting portion 32d penetrates the through hole 22h of the projecting portion 22 of the cell holder 20 located on the side surface 13c side of the battery cell 11 and the projecting portion 31d of the main body base 30BS when viewed from the arrangement direction A. Overlaps with hole H.

The bolt 41 of the fastening member 4 is inserted into the through hole H of the protruding portion 32b. The bolt 43 of the fastening member 4 is inserted into the through hole H of the protruding portion 32d. That is, the bolt 41 includes the through hole 21h of the cell holder 20, the through hole of the middle plate 7, the through hole H of the protruding portion 31b of the fixing member 3, and the protruding portion at the end B1 of the main body portion 30 in the direction B. It is inserted into the through hole H of 32b. The bolt 43 has a through hole 22h of the cell holder 20, a through hole of the middle plate 7, a through hole H of the protruding portion 31d of the fixing member 3, and a protruding portion 32d at the end B2 of the body portion 30 in the direction B. It is inserted into the through hole H. Therefore, in the present embodiment, the projecting portions 31b, 31d, 32b, 32d are connected to the main body 30 by the fastening members 4 (bolts 41, 43) at the ends B1, B2 (both ends) of the main body 30 in the direction B. A pair of fastening parts 31, 31 to be fastened.

In the direction B, the plate member 33 extends in the region sandwiched by the protruding portions 32b and 32d with the protruding portions 32b and 32d as both ends. That is, the reinforcing portion 32 is formed at least in a region sandwiched by the pair of fastening portions 31, 31 of the main body portion 30.

Here, bending stress acts on the main body 30 such that the main body 30 is bent in the arrangement direction A with the fastening portion 31 by the fastening member 4 as a fixed end. Specifically, as shown in FIG. 5, when the battery cells 11 expand, for example, as the deterioration of the battery cells 11 progresses, the array ends of the array bodies 2 a press the fixing members 3 and the fixing members 3 are arranged in the arrangement direction. Deformation into A will occur. At this time, in the fixing member 3, the bending stress (bending moment) increases as the distance from the fastening portion 31 increases. Therefore, the deformation of the fixing member in the first direction is unlikely to occur at the fastening portion and is likely to occur at a portion away from the fastening portion.

In the example of FIG. 5, the main body portion 30 is fastened by the bolts 41 and 43 at the plurality of fastening portions 31 located at the ends B1 and B2 in the direction B. In this case, bending stress acts on the main body 30 such that the main body 30 is bent in the arrangement direction A with the respective fastening portions 31 as fixed ends. As a result, the main body portion 30 is deformed so that the portion of the main body portion 30 sandwiched by the fastening portions 31 bulges in the direction opposite to the array 2a in the array direction A. In particular, in the battery pack 100, since the fixing portion 35 of the fixing member 3 is fixed to the wall surface 1s of the housing 1, the bulging deformation of the main body portion 30 causes the main body portion 30 to be deformed toward the tip end rather than the base end side. It tends to occur on the side.

With respect to such bending stress, the reinforcing portion 32 configured as described above has the fastening portion 31 by the fastening member 4 as the fixed end in the arrangement direction on the distal end side of the main body portion 30 rather than the proximal end side of the main body portion 30. The rigidity against bending stress acting on the main body portion 30 so as to bend the main body portion 30 to A is improved.

As described above, according to the battery pack 100 and the battery module 2 according to the present embodiment, the reinforcing portion 32 acts on the main body portion 30 so as to bend the main body portion 30 in the arrangement direction A with the fastening portion 31 as the fixed end. Since the rigidity against the bending stress is increased, the bending deformation of the main body 30 such that the portion sandwiched by the fastening portions 31 bulges in the arrangement direction A is suppressed. Bending of the fastening member 4 due to deformation of the main body portion 30 is suppressed. Therefore, it is possible to reduce the occurrence of stress concentration on the fastening member 4 due to the deformation of the fixing member 3.

In the battery pack 100 and the battery module 2, the reinforcing portion 32 is formed on the side farther from the housing 1 than the central portion M of the body portion 30 (the tip side of the body portion 30). Thereby, the bending rigidity can be surely improved at the tip end side of the main body portion 30.

In the battery pack 100 and the battery module 2, the main body portion 30 is fastened with the bolts 41 and 43 at the end portions B1 and B2 which are both end portions in the direction B (direction substantially parallel to the wall surface 1s) intersecting the arrangement direction A. It includes a pair of fastening portions 31, 31 (protruding portions 31b, 31d and protruding portions 32b, 32d). The reinforcing portion 32 is formed at least in a region sandwiched by the pair of fastening portions 31, 31 of the main body portion 30. As a result, the bending rigidity of the portion of the main body portion 30 sandwiched by the pair of fastening portions 31, 31 is improved, so that the deformation of the fixing member that bulges outward in the first direction can be suppressed.

In the battery pack 100 and the battery module 2, the reinforcing portion 32 has a thickness TH2 of the main body portion 30 on the side farther from the housing 1 than the central portion M of the main body portion 30 (the tip side of the main body portion 30). The thicker portion is thicker than the thickness TH1 of the main body portion 30 on the side closer to the housing 1 than the central portion M (the proximal end side of the main body portion 30). Particularly, the reinforcing portion 32 is a plate member 33 provided on the outer surface 30s along the main body portion 30. Thereby, the reinforcing portion 32 can be easily formed.

In the battery pack 100 and the battery module 2, the reinforcing portion 32 has a through hole H through which the plurality of fastening members 4 (bolts 41, 43) are inserted in each of the protruding portions 32b, 32d. Accordingly, by inserting the bolts 41 and 43 into the through holes H of the protruding portions 32b and 32d, respectively, it is possible to perform joint tightening for fastening the reinforcing portion 32 and the main body portion 30 with the common bolts 41 and 43.

In the battery pack 100 and the battery module 2, the fixing portion 35 includes a plate-shaped member extending along the wall surface 1s with the length L. The dimension of the main body 30 along the wall surface 1s including the reinforcing portion 32 is smaller than the length L of the fixing portion 35 along the wall surface 1s. Thereby, since the main body 30 and the reinforcing portion 32 can be provided within the range of the length L along the wall surface 1s of the fixed portion 35, the reinforcing portion 32 may be projected more than the fixed portion 35 in the direction along the wall surface 1s. Absent. As a result, the space inside the housing 1 can be effectively used.

The battery module 2 further includes an elastic member 8 arranged at one of the array ends of the array 2a (for example, one end 2b). The reinforcing portion 32 is provided on the main body portion 30 of the fixing member 3 at the one end 2b where the elastic member 8 is arranged among the pair of fixing members 3 and 3. As a result, the bending rigidity of the main body portion 30 of the fixing member at the one end 2b on which the elastic member 8 is arranged can be increased, so that the bending deformation of the main body portion 30 can be suitably suppressed.

The above-described embodiment described above describes one embodiment of the battery pack and the battery module according to the present invention. Therefore, the battery pack and the battery module according to the present invention are not limited to those described above. The battery pack and the battery module according to the present invention can be arbitrarily modified from those described above without departing from the scope of the claims.

For example, in the battery pack 100 and the battery module 2, the fixing member 3 can be deformed as follows.

In the above-described embodiment, as the reinforcing portion, the plate member 33 (reinforcing portion 32) which is separate from the main body base portion 30BS and is provided on the outer surface 30s along the main body portion 30 at the tip end side of the main body portion 30 is illustrated. However, the reinforcing portion may be provided with a rib protruding from the outer surface 30s. The fixing member 3A according to the first modification will be described with reference to FIG.

As shown in FIG. 6, in the fixing member 3A, the reinforcing portion 32A has a pair of ribs 32r formed on the side farther from the housing 1 than the central portion M of the body portion 30 (the tip side of the body portion 30). Including 32r. Each of the pair of ribs 32r, 32r is integrally formed with the main body base 30BS so as to project from the outer surface 30s. The rib 32r is, for example, a rib having a rectangular cross section.

The rib 32r extends along the direction B on the tip side of the main body 30. One of the pair of ribs 32r, 32r has a protruding portion 31b located at the tip end side of the body portion 30 at the end B1 and a protruding portion 31c located at the base end side of the body portion 30 at the end portion B2. It extends to tie. The other of the pair of ribs 32r, 32r includes a protruding portion 31a located on the base end side of the body portion 30 at the end portion B1 and a protruding portion 31d located on the tip end side of the body portion 30 at the end portion B2. It extends to tie. That is, the reinforcing portion 32A is formed at least in a region sandwiched by the pair of fastening portions 31 and 31 of the main body portion 30 in the direction intersecting the arrangement direction A and the direction B (here, the Y direction).

The pair of ribs 32r, 32r intersect with each other at an intermediate portion in the direction B. Therefore, the pair of ribs 32r and 32r extend in the direction sandwiched by the protruding portions 31b and 31d in the direction B with the protruding portions 31b and 31d at both ends on the tip side of the main body portion 30. Further, the pair of ribs 32r, 32r extend on the base end side of the main body portion 30 in the direction B in a region sandwiched by the projecting portions 31a, 31c with the projecting portions 31a, 31c as both ends. That is, the reinforcing portion 32A is formed at least in the region sandwiched by the pair of fastening portions 31, 31 of the main body portion 30 in the direction B as well.

As described above, according to the reinforcing portion 32A, the bending rigidity of the main body portion 30 can be effectively improved by the pair of ribs 32r, 32r extending along the direction B. Further, since the bending rigidity of the portion sandwiched by the protruding portions 31a, 31b, 31c, 31d is improved, it is possible to suppress the deformation of the fixing member such that this portion bulges outward in the arrangement direction A.

In the above-described embodiment or modified example, the configuration in which the reinforcing portions 32 and 32A are formed on the outer surface 30s of the main body portion 30 has been exemplified, but instead of this configuration, the reinforcing portion is provided on the inner surface (main surface) 30t of the main body portion 30. It may be configured to be formed. The fixing member 3B according to the second modification will be described with reference to FIGS.

As shown in FIGS. 7 and 8, in the fixing member 3B, the reinforcing portion 32B is formed on the inner surface 30t of the main body portion 30 on the array body 2a side. The reinforcing portion 32B includes a rib 32s and a rib 32t.

The rib 32s is integrally formed with the main body base 30BS so as to project from the inner surface 30t. The rib 32s is formed along the outer edge of the body base 30BS on the tip side of the body 30. The rib 32s extends along the direction B at a portion along the outer edge 30c on the tip side of the main body portion 30. That is, the portion of the rib 32s along the outer edge 30c on the tip side of the main body portion 30 extends in the direction B with the projecting portions 31b and 31d as both ends in a region sandwiched by the projecting portions 31b and 31d. That is, the reinforcing portion 32B is formed at least in the direction B in a region sandwiched by the pair of fastening portions 31, 31 of the main body portion 30.

The rib 32t is formed integrally with the main body base 30BS so as to project from the inner surface 30t. The rib 32t extends along the Y direction in a region surrounded by the rib 32s when viewed in the X direction. On the inner surface 30t of the main body base portion 30BS, a plurality of elastic members 8B are arranged in a portion sandwiched by the ribs 32s and the ribs 32t (see FIG. 9). Each of the elastic members 8B is different from the elastic member 8 in that it has a shape corresponding to a portion sandwiched by the ribs 32s and the ribs 32t. The plurality of elastic members 8B may have the same outline as the elastic member 8 as a whole in a state of being arranged in a portion sandwiched by the ribs 32s and the ribs 32t.

The protrusion height of the rib 32s from the inner surface 30t increases toward the tip of the main body 30. The protruding height TH4 from the inner surface 30t of the rib 32s on the tip side of the main body portion 30 is not particularly limited. The protruding height TH5 of the rib 32t from the inner surface 30t is substantially equal to the protruding height of the rib 32s on the base end side of the main body 30. The protrusion height TH5 is lower than the protrusion height TH4 of the rib 32s on the tip side of the main body portion 30 and smaller than the thickness of the elastic member 8B.

According to the reinforcing portion 32B, for example, the protrusion height TH4 can be made larger than the thickness of the elastic member 8B within a range in which the rib 32s does not interfere with the battery cell 11 or the cell holder 20. This makes it possible to further improve the bending rigidity on the tip side of the main body portion 30 by utilizing the space on the array body 2a side in the main body portion 30. Instead of the rib 32t, a rib extending along the direction B may be formed in a region surrounded by the rib 32s when viewed in the X direction. In this case, in addition to the rib 32s, the rib functions as the reinforcing portion 32B.

In the above-described embodiment or modification, the fixing members 3, 3A, 3B each have the fixing portion 35, and the fixing members 3, 3A, 3B are attached to the housing 1 by the fixing portion 35. However, instead of this configuration, the fixing members 3, 3A, 3B may not have the fixing portion 35, and the fixing members 3, 3A, 3B may be attached to the housing 1 by using separate angle members or the like. Good. A fixing member 3C according to the third modification will be described with reference to FIG. Here, in the state where the fixing member 3C is fixed to the wall surface 1s (see FIG. 1) of the housing 1 (hereinafter, also simply referred to as “fixed state”), the direction intersecting the wall surface 1s is the Y direction.

The reinforcement portion 32C is, for example, a thick portion formed from the base end side to the tip end side of the main body portion 30. The reinforcing portion 32C is integrally formed with the main body base 30BS by making the main body base 30BS itself thick on the outer surface 30s side of the main body 30.

The thickness of the main body 30 on the base end side is equal to the thickness TH1 of the main body base 30BS, for example. The thickness of the body portion 30 on the tip side is a thickness TH6 which is larger than the thickness TH1 of the body base portion 30BS. That is, in the reinforcing portion 32C, the thickness of the main body portion 30 increases as the distance from the housing 1 increases in the fixed state. Therefore, in the fixed state, the reinforcing portion 32C has higher rigidity with respect to bending stress as it separates from the housing 1 in the direction (Y direction) intersecting the wall surface 1s.

According to the reinforcing portion 32C, the rigidity with respect to the bending stress of the main body portion 30 increases as the distance from the housing 1 increases, so that the bending deformation of the main body portion 30 in the portion away from the housing 1 can be appropriately suppressed.

The modification of the fixing member 3 is not limited to the above-mentioned fixing member 3A, fixing member 3B, and fixing member 3C. For example, some of the configurations of the fixing member 3A, the fixing member 3B, and the fixing member 3C may be selected or may be combined with each other.

In the above-described embodiment or modification, the reinforcing portions 32 to 32C are formed on the outer surface 30s or the inner surface 30t of the body portion 30, but may be formed on both the outer surface 30s and the inner surface 30t.

DESCRIPTION OF SYMBOLS 1... Housing, 1s... Wall surface, 2... Battery module, 2a... Array, 2b... One end (one of array ends), 3... Fixing member, 4... Fastening member, 8... Elastic member, 11... Battery cell, 30 ... body part, 30s... outer surface (main surface), 30t... inner surface (main surface), 31... fastening part, 32... reinforcing part, 33... plate member, 35... fixing part, 100... battery pack, A... array direction, B... direction (second direction), H... through hole (insertion hole), M... central portion.

Claims (11)

A battery pack in which a battery module is housed in a housing,
The battery module is
An array including a plurality of battery cells arranged along the first direction,
A pair of fixing members each having a flat plate-shaped main body arranged to sandwich the array in the first direction, and a fixing portion fixed to a wall surface of the housing;
A plurality of fastening members that fasten the body portions to each other and apply a restraining load to the array body in the first direction;
An elastic member disposed on one of the array ends of the array,
A reinforcing portion that improves rigidity against bending stress acting on the main body portion such that the main body portion is bent in the first direction with the fastening portion by the fastening member as a fixed end intersects with the first direction in the main body portion. It is formed on at least one main surface,
The battery pack, wherein the reinforcing portion is provided on the main body portion of the fixing member on the side where the elastic member is arranged among the pair of fixing members. The main body portion includes a pair of fastening portions fastened by the fastening members at both ends in a second direction intersecting the first direction,
The reinforcing portion, the is at least formed in a region sandwiched by the pair of fastening portions of the main body, according to claim 1 battery pack according. The battery pack according to claim 2 , wherein the second direction is a direction parallel to the wall surface. The reinforcing portion projects from the main surface, comprising a rib extending along the second direction, according to claim 2 or 3 battery pack according. The reinforcing portion, in the direction crossing the wall surface, the rigidity is increased relative to the bending stress with increasing distance from the housing, any one battery pack according to claim 1-4. In the reinforcing portion, the thickness of the main body portion on the side farther from the housing than the central portion of the main body portion is greater than the thickness of the main body portion on the side closer to the housing than the central portion of the main body portion. meat is a thick portion, any one battery pack according to claim 1-5. The battery pack according to claim 6 , wherein the reinforcing portion is a plate member provided on the main surface along the main body portion. It said reinforcing portion includes an insertion hole for inserting said plurality of fastening members, any one battery pack according to claim 1-7. The fixing portion includes a plate-shaped member extending in a predetermined dimension along the wall surface,
The dimension along the wall surface of the main body portion including the reinforcement portion, the smaller than the predetermined size of the fixed portion, or the battery pack of one of claims 1-8. The reinforcing portion, the formed farther from the housing than the central portion of the body portion, any one battery pack according to claim 1-9. An array including a plurality of battery cells arranged along the first direction,
A pair of fixing members each having a flat plate-shaped main body arranged to sandwich the array in the first direction;
A plurality of fastening members that fasten the body portions to each other and apply a restraining load to the array body in the first direction;
An elastic member disposed on one of the array ends of the array,
A reinforcing portion that improves rigidity against bending stress acting on the main body portion such that the main body portion is bent in the first direction with the fastening portion by the fastening member as a fixed end intersects with the first direction in the main body portion. It is formed on at least one main surface,
The battery module, wherein the reinforcing portion is provided in the main body portion of the fixing member on the side where the elastic member is arranged among the pair of fixing members.

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