Heat exchanger and buffer member

Abstract

To suppress concentration of load.SOLUTION: A heat exchanger is an apparatus for performing heat exchange with a battery cell, and includes an outer shell member having a flow path of a heat exchange medium, and a buffer member having elasticity. The outer shell member includes a first wall portion and a second wall portion that faces the first wall portion with the flow path of the heat exchange medium interposed therebetween. The buffer member is arranged in the flow path of the heat exchange medium along the first and second wall portions, and has a configuration in which a generated distance becomes longer toward a central portion along a first direction substantially parallel to the first and second wall portions, and / or a restoring force becomes lower toward the central portion along the first direction. The generated distance is a distance required to displace a part of the first or second wall portion in order to generate the restoring force of the buffer member.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a heat exchanger and a buffer member for use with a battery cell. [Background technology]

[0002] The stacked cooler described in Patent Document 1 has multiple stacked cooling pipes and is configured to cool electronic components placed between these cooling pipes. Each cooling pipe has a flat shape, and to improve cooling capacity, two corrugated inner fins are arranged inside each cooling pipe so that they overlap in the thickness direction of the cooling pipe. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-191527 Summary of the Invention [Problem to be solved by the invention]

[0004] In this case, it is assumed that battery cells are placed between the cooling pipes of a stacked cooler to cool them, but the center of the battery cell may expand due to deterioration of the battery material, which may cause loads to concentrate in the center of the cooling pipes and inner fins.

[0005] In one aspect of the present disclosure, it is desirable to suppress load concentration. [Means for solving the problem]

[0006] One aspect of the present disclosure is a heat exchanger configured to exchange heat with a battery cell, the heat exchanger comprising an outer shell member and a buffer member. The outer shell member has a heat exchange medium flow path provided therein. The buffer member is disposed in the heat exchange medium flow path and has elasticity. The outer shell member has a first wall portion extending in a substantially planar shape and a second wall portion that faces the first wall portion in the facing direction across the heat exchange medium flow path and extends substantially parallel to the first wall portion. The outer shell member is configured to abut against the battery cell at the first and / or second wall portions. The buffer member is disposed along the first and second wall portions and is configured such that the generation distance increases toward the center along the first direction and / or the restoring force decreases toward the center along the first direction. The first direction is a direction substantially parallel to the first and second wall portions. The generation distance is the distance that a portion of the first or second wall portion needs to be displaced in the facing direction to generate the restoring force of the buffer member.

[0007] With this configuration, when the center of the battery cell expands, the buffer member can be deformed appropriately to accommodate this expansion, thereby preventing the concentration of load on the heat exchanger and the battery cell.

[0008] In one aspect of the present disclosure, the buffer member may be configured such that the generation distance increases toward the center along the first direction. According to the above configuration, when the central portion of the battery cell expands, the buffer member can be prevented from being excessively deformed and plastically deformed.

[0009] In one aspect of the present disclosure, the buffer member may be configured such that the generated distance increases toward the center along the first direction and the generated distance increases toward the center along the second direction, and / or the restoring force decreases toward the center along the first direction and the restoring force decreases toward the center along the second direction. The second direction may be substantially parallel to the first and second wall portions and substantially perpendicular to the first direction.

[0010] With this configuration, when the center of the battery cell expands, the buffer member can be deformed appropriately to better accommodate this expansion, thereby reducing the concentration of load on the heat exchanger and the battery cell.

[0011] In one aspect of the present disclosure, the buffer member may include a plurality of first leaf springs arranged along the first and second wall portions. Each of the plurality of first leaf springs may have a main body portion and at least one groove portion. The groove portion protrudes from the main body portion in the facing direction. Each of the plurality of first leaf springs may be arranged to extend along the first and second wall portions. At least one groove portion in one of two adjacent first leaf springs may protrude toward the first wall portion, and at least one groove portion in the other may protrude toward the second wall portion.

[0012] According to the above configuration, the heat exchange medium can be agitated, thereby enabling better heat exchange between the battery cells. In one embodiment of the present disclosure, the cushioning member may include a plurality of second leaf springs arranged side by side along the first and second wall portions, each of which has a unique shape and / or restoring force and may have a root portion and two side portions protruding from the root portion.

[0013] According to the above configuration, the generated distance and / or the restoring force can be suitably distributed. In one aspect of the present disclosure, the buffer member may be configured as a leaf spring and may have a plurality of grooves protruding in the facing direction. The plurality of grooves may be aligned along a first direction. The buffer member may be configured such that the height of the grooves decreases toward a center portion along the first direction, thereby increasing the generation distance toward the center portion along the first direction.

[0014] According to the above configuration, the generation distance can be suitably distributed. One aspect of the present disclosure is a buffer member configured to be placed facing a substantially planar main surface of a battery cell. The buffer member is placed along the main surface and configured so that the generated distance increases toward the center along a first direction and / or the restoring force decreases toward the center along the first direction. The first direction is a direction substantially parallel to the main surface. The generated distance is the distance that each portion of the main surface needs to be displaced in a direction substantially perpendicular to the main surface in order to generate a restoring force of the buffer member.

[0015] With this configuration, when the center of the battery cell expands, the cushioning member can be deformed appropriately to accommodate this expansion, thereby preventing the concentration of load on the cushioning member and the battery cell. [Brief explanation of the drawings]

[0016] [Figure 1] Fig. 1A is a plan view of the heat exchanger of the first embodiment, Fig. 1B is a side view of a plurality of heat exchangers of the first embodiment stacked together with battery cells, and Fig. 1C is a partial perspective view transparently showing the heat exchanger of the first embodiment. [Figure 2] 2A and 2B are side views of a first leaf spring disposed in a flow path of a heat exchange medium. [Figure 3] Fig. 3A is a partial perspective view transparently showing the heat exchanger of the first embodiment, and Fig. 3B is a side view of two types of first leaf springs arranged in a flow path of a heat exchange medium. [Figure 4] Fig. 4A is an explanatory diagram showing the change in spring constant along the short side direction of a first leaf spring of a modified example of the first embodiment, and Fig. 4B is an explanatory diagram showing the change in spring constant along the long side direction of a buffer member (in other words, a plurality of leaf springs) of a modified example of the first embodiment. [Figure 5] FIG. 5 is a side view of a first leaf spring disposed in a flow path in a modified example of the first embodiment. [Figure 6]Fig. 6A is a perspective view of a buffer member (i.e., a plurality of second leaf springs) of a second embodiment arranged in a flow path of a heat exchanger. Fig. 6B is a perspective view of a plurality of second leaf springs located around the center of an end row, viewed along the short side. Fig. 6C is a perspective view of a plurality of second leaf springs located around the center of a central row, viewed along the short side. [Figure 7] Fig. 7A is an explanatory diagram of blocks of first and second wall portions in a modified example of the second embodiment, and Fig. 7B is a side view of the leaf spring of the modified example of the second embodiment as viewed along the short side direction. [Figure 8] Fig. 8A is a plan view of a buffer member (in other words, a plurality of second leaf springs) according to a modified example of the second embodiment, and Fig. 8B is a side view of the buffer member according to the third embodiment. [Figure 9] 9A and 9B are perspective and side views of the cushioning member of the third embodiment. [Figure 10] FIG. 10 is an explanatory diagram of a battery cell that has expanded due to aging. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First embodiment] [(1) Overview of the heat exchange system] 1A to 1C is used for heat exchange (for example, cooling) of a battery mounted on a vehicle. The battery is used as a power source for a motor used to run a vehicle configured as an electric vehicle or a hybrid vehicle. Of course, the battery may also be used for other purposes.

[0018] The heat exchange system 1 includes a plurality of heat exchangers 10. The heat exchanger 10 is made of, for example, a metal material such as aluminum or stainless steel, and includes an outer shell member 11, a flow path 16, an inlet portion 17, and an outlet portion 18.

[0019] The shell member 11 is a long, thin member extending in the longitudinal direction L. The shell member 11 is a flat member that extends in a substantially planar shape along the longitudinal direction L and the lateral direction S, and has a flow path 16 for the heat exchange medium formed therein (see FIGS. 1C to 2B). The lateral direction S is a direction that is substantially perpendicular to the longitudinal direction L. The shell member 11 is formed by joining two plate-like members, and has first and second wall portions 12 and 13, a side wall portion 14, and an end portion 15. The heat exchange medium may be, for example, water or oil, which has high insulation resistance.

[0020] The first and second wall portions 12, 13 are elongated plate-like portions that extend in a substantially planar manner substantially parallel to the longitudinal direction L and the lateral direction S, and are arranged substantially parallel to each other to form a flat gap. In other words, the first and second wall portions 12, 13 face each other in the thickness direction of the outer shell member 11, and a flat flow path 16 is formed between them. The thickness direction T is a direction that is substantially perpendicular to the longitudinal direction L and the lateral direction S.

[0021] Side wall portion 14 is a wall-like portion that protrudes from the edges of first and second wall portions 12, 13 in the facing direction in which first and second wall portions 12, 13 face each other, in other words, in the thickness direction T of outer shell member 11, and is provided so as to surround first and second wall portions 12, 13. In other words, a flow path 16 is formed by the space surrounded by side wall portion 14 and first and second wall portions 12, 13.

[0022] The end portion 15 is located approximately in the center in the thickness direction T, and is formed by joining flange-like portions provided on two plate-like members that form the outer shell member 11, for example, by welding or brazing.

[0023] The inlet portion 17 and the outlet portion 18 are provided at both ends of the outer shell member 11 in the longitudinal direction L (see FIGS. 1A and 1B). The inlet portion 17 and the outlet portion 18 each have two cylindrical portions protruding from the first and second wall portions 12 and 13, respectively, and these portions are aligned coaxially. The interiors of the inlet portion 17 and the outlet portion 18 are each connected to the flow path 16, so that the heat exchange medium flows into the flow path 16 through the inlet portion 17, and the heat exchange medium that has passed through the flow path 16 flows out from the outlet portion 18 to the outside.

[0024] The heat exchangers 10 are stacked in the thickness direction T of the outer shell member 11 so that the first wall portion 12 and the second wall portion 13 of two adjacent heat exchangers 10 face each other, and battery cells 4 are disposed between the first wall portion 12 and the second wall portion 13. The battery cells 4 are, for example, flat and elongated, and have two main surfaces 40 that extend in a generally planar shape and face each other in the thickness direction. For example, these main surfaces 40 are generally rectangular and disposed generally parallel to each other. The first and second walls 12, 13 abut against the main surfaces 40 of the battery cells 4, and heat exchange with the battery cells 4 is performed by the heat exchange medium flowing through the flow paths 16.

[0025] The inlet portions 17 of the heat exchangers 10 are connected to each other, and the outlet portions 18 are connected to each other, so that the heat exchange medium flows in through the inlet portion 17 of the heat exchanger 10 located at the end. The heat exchange medium passes through the inlet portion 17 of each heat exchanger 10 and flows into the flow path 16. The heat exchange medium that flows out of the flow path 16 of each heat exchanger 10 reaches the outlet portion 18 of the heat exchanger 10 located at the end, and flows out to the outside.

[0026] [(2) Cushioning material] Elastic buffer members 2 are arranged along the first and second walls 12, 13 throughout the entire flow path 16 of the heat exchange medium in each heat exchanger 10 of the heat exchange system 1 (see FIGS. 1C to 2B). The buffer members 2 are members for absorbing impacts applied to the heat exchanger 10 and protecting the heat exchanger 10. The buffer members 2 have a plurality of substantially rectangular first leaf springs 3, and each first leaf spring 3 is arranged so that its end corresponding to its long side extends along the longitudinal direction L and its end corresponding to its short side extends along the lateral direction S. As an example, each first leaf spring 3 extends along (or substantially parallel to) the first and second walls 12, 13 from near one end of the flow path 16 to near the other end in the lateral direction S, and is aligned in a row in the longitudinal direction L.

[0027] Each of the first leaf springs 3 is made of a metal material such as aluminum or stainless steel, for example. It is preferable that each of the first leaf springs 3 is made of the same metal material as the outer shell member 11. This can suppress potential difference corrosion.

[0028] [(3) Details of the first leaf spring] Each first leaf spring 3 includes a main body 30, one center groove 31, and two end grooves 32 (hereinafter also simply referred to as grooves) (see FIGS. 1C to 2B).

[0029] The main body 30 is a generally rectangular plate-like portion that extends in a generally flat plane. Each groove is a groove-shaped portion that protrudes from the main body 30 toward the second wall 13 in the thickness direction T, and extends in the longitudinal direction L from one end to the other end of the main body 30. The cross section of each groove perpendicular to the longitudinal direction L is, for example, arc-shaped. Of course, the shape of the cross section of each groove is not limited to this, and may be, for example, V-shaped.

[0030] In addition, each groove portion is aligned along the short-side direction S, with the middle groove portion 31 being positioned approximately in the center of the short-side direction S, and the two end groove portions 32 being positioned on either side of the middle groove portion 31 at approximately the same intervals.

[0031] Each groove has a substantially uniform height H from one end to the other in the longitudinal direction L. The heights H of the two end grooves 32 are substantially the same, and the height H of the central groove 31 is lower than that of the end groove 32. The height H of a groove refers to the maximum distance from one end to the other in the direction substantially perpendicular to the main body 30 (in other words, the thickness direction T) in the cross section of the groove (see FIGS. 2A and 2B). Hereinafter, the portion of the groove farthest from the main body 30 in that direction in the cross section will also be referred to as the bottom.

[0032] When a force is applied in the direction of the groove height H, each first leaf spring 3 elastically deforms and generates a restoring force. Furthermore, as an example, the distribution of the spring constant (hereinafter simply referred to as the spring constant) of each first leaf spring 3 when a force is applied in that direction is approximately uniform. In other words, regardless of which part of the first leaf spring 3 a force of the same magnitude is applied in that direction, the first leaf spring 3 generates approximately the same restoring force. Furthermore, as an example, the spring constants of each first leaf spring 3 are approximately the same.

[0033] The first leaf springs 3 are arranged such that the grooves protrude in the same direction. For example, the body 30 of each first leaf spring 3 is located on the first wall 12 side, and the bottom of each groove protrudes toward the second wall 13 side.

[0034] However, this is not limiting, and as shown in Figures 3A and 3B, each first leaf spring 3 may be arranged so that its groove protrudes in a different direction from the grooves of adjacent first leaf springs 3. That is, first leaf springs 3 having grooves protruding toward the first wall 12 and first leaf springs 3 having grooves protruding toward the second wall 13 may be arranged alternately. Alternatively, all first leaf springs 3 may be arranged so that their grooves protrude in a different direction from their adjacent first leaf springs 3. Furthermore, for example, some of the first leaf springs 3, specifically, first leaf springs 3 located away from the ends in the longitudinal direction L, may be arranged so that their grooves protrude in a different direction from their adjacent first leaf springs 3.

[0035] Furthermore, each first leaf spring 3 is disposed in the flow path 16 without being fixed to the outer shell member 11. For this reason, in FIG. 2B , as an example, the first leaf spring 3 abuts against the first wall 12 and is spaced apart from the second wall 13. However, this is not limiting, and it is also possible that the first leaf spring 3 in FIG. 2B is spaced apart from the first and second walls 12, 13, or is spaced apart from the first wall 12 and abuts against the second wall 13.

[0036] [(4) Distance] As described above, each first leaf spring 3 of the cushioning member 2 is not fixed to the outer shell member 11 (see FIGS. 2A and 2B). Furthermore, the height H of the center groove 31 and the height H of the end groove 32 of each first leaf spring 3 are uniquely determined, and the height H of the groove of each first leaf spring 3 may not match the height H of the groove of another first leaf spring 3.

[0037] 2A, there may be a first leaf spring 3 in which the height H of the end groove 32 and the length in the thickness direction T of the flow channel 16 are approximately the same, and the bottom 32A of the end groove 32 and the main body 30 abut against the first and second wall portions 12 and 13, respectively. Alternatively, there may be a first leaf spring 3 in which the height H of the end groove 32 is smaller than the height of the flow channel 16, and a gap is formed between the bottom 32A of the end groove 32 and / or the main body 30 and the first and second wall portions 12 and 13, as shown in FIG. 2B. The height of the flow channel 16 refers to the distance from one end of the flow channel 16 to the other end in the thickness direction T.

[0038] When the first wall 12 facing the first leaf spring 3 where such a gap occurs is pressed, the pressed portion (hereinafter referred to as the pressing portion) or its periphery comes into contact with the first leaf spring 3, and after the first leaf spring 3 comes into contact with the second wall 13, a restoring force is generated in the first leaf spring 3. Similarly, when the second wall 13 facing the first leaf spring 3 is pressed, the pressing portion or its periphery comes into contact with the first leaf spring 3, and after the first leaf spring 3 comes into contact with the first wall 12, a restoring force is generated in the first leaf spring 3.

[0039] In other words, when the pressing portion is displaced a certain distance, the first leaf spring 3 is pressed from both sides by the first and second walls 12, 13, and a restoring force is generated in the first leaf spring 3. Hereinafter, the distance that the pressing portion of the first or second wall 12, 13 needs to be displaced in the thickness direction T to generate a restoring force in the first leaf spring 3 is referred to as the "generation distance." The generation distance is determined by the height H of the groove located near the pressing portion of the first or second wall 12, 13.

[0040] [(5) Distribution of occurrence distance] The cushioning member 2 is configured so that the generated distance increases toward the central portion C in the longitudinal direction L, and also increases toward the central portion C in the lateral direction S (see FIGS. 1C to 2B). The central portion C is a portion of the cushioning member 2 that is located at or near the center in the longitudinal direction L and the lateral direction S.

[0041] Each of the first and second walls 12, 13 has a plurality of blocks B, which are substantially rectangular regions (see FIG. 1C). The blocks B are located in front of each first leaf spring 3 and have substantially the same shape as the first leaf spring 3 on the front side. That is, in the first or second wall 12, 13, the blocks B extend from one end to the other in the short-side direction S and from one end to the other in the longitudinal direction L of the first leaf spring 3 on the front side. Furthermore, in each of the first and second walls 12, 13, a plurality of blocks B are arranged adjacent to each other across the longitudinal direction L.

[0042] As described above, each first leaf spring 3 has a central groove 31 and two end grooves 32 extending from one end of the body 30 to the other along the longitudinal direction L. These grooves are aligned along the lateral direction S, with the central groove 31 located between the two end grooves 32. The height H of the two end grooves 32 is greater than the height H of the central groove 31.

[0043] By adjusting the height of the grooves in this manner, the generated distance in each block B is distributed so that it gradually increases toward the center C along the short-side direction S. However, as shown in FIG. 2A , it is assumed that the height H of each end groove 32 is the same as the height of the flow path 16. In such a case, the generated distance is approximately zero in the two regions B0 located in front of each end groove 32. However, in the region B1 between these regions, the generated distance increases toward the center C along the short-side direction S. Furthermore, the generated distance may be approximately constant even in regions near grooves in each block B whose height H is lower than the height of the flow path 16. In other words, the generated distance may be distributed approximately uniformly in parts of the buffer member 2 along the short-side direction S.

[0044] On the other hand, in each block B, the generated distance is distributed approximately uniformly along the longitudinal direction L. However, the height H of the end groove portion 32 and the height H of the middle groove portion 31 of each first leaf spring 3 are smaller as it is positioned closer to the central portion C. Therefore, in the buffer member 2, the generated distance changes when crossing the boundary between blocks B. That is, in the buffer member 2, the generated distance is distributed so that it gradually increases as it moves along the longitudinal direction L toward the central portion C. Of course, this is not a limitation, and in the buffer member 2, the generated distance may be distributed so that it gradually increases as it moves along the longitudinal direction L toward the central portion C.

[0045] [(6) Modification] In the first embodiment, the spring constants of the first leaf springs 3 (in other words, the entire cushioning member 2) are distributed approximately uniformly, and the spring constants of the first leaf springs 3 are approximately the same. However, in a modification of the first embodiment, the cushioning member 2 is configured so that the spring constant decreases toward the center C in the longitudinal direction L and decreases toward the center C in the lateral direction S (FIGS. 4A and 4B). In other words, the restoring force of the cushioning member 2 decreases toward the center C in both the longitudinal direction L and the lateral direction S, given the same amount of displacement.

[0046] That is, in each first leaf spring 3, the spring constant is distributed so as to gradually decrease along the short side direction S toward the center C. Of course, this is not limited to this, and in each first leaf spring 3, the spring constant may be distributed so that the spring constant decreases in stages along the short side direction S toward the center C.

[0047] On the other hand, the distribution of the spring constants of each first leaf spring 3 along the longitudinal direction L is approximately uniform. Furthermore, when comparing the spring constants of each first leaf spring 3 at the same position in the short direction S, the spring constant at that position is smaller for first leaf springs 3 located closer to the center C along the longitudinal direction L. In other words, in the cushioning member 2 of this modified example, the spring constants are distributed so that they gradually decrease as you move toward the center C along the longitudinal direction L. Of course, this is not a limitation, and in the cushioning member 2, the spring constants may be distributed so that they gradually decrease as you move toward the center C along the longitudinal direction L.

[0048] Furthermore, while the spring constant of each first leaf spring 3 is set as described above, the buffer member 2 may be configured so that the generated distance is approximately uniform. In other words, the height H of each groove included in each first leaf spring 3 may be approximately the same (see FIG. 5).

[0049] In this modification, the first leaf springs 3 are also arranged so that the grooves protrude in the same direction. However, this is not limiting, and the grooves of each first leaf spring 3 may protrude in a different direction from the grooves of adjacent first leaf springs 3.

[0050] [2. Second Embodiment] [(1) Overview] The heat exchange system 1 of the second embodiment differs from that of the first embodiment in the configuration of the buffer member 2 provided in the heat exchanger 10 (see FIGS. 6A to 6C). Below, the differences between the heat exchange system 1 of the second embodiment and the first embodiment will be described.

[0051] [(2) Cushioning material] The buffer member 2 of the second embodiment has a plurality of second leaf springs 5 ​​and a plurality of support portions 52 (see FIGS. 6A to 6C). Each second leaf spring 5 and each support portion 52 is disposed in the flow path 16 of the heat exchanger 10 and is made of a metal material such as aluminum or stainless steel. It is desirable that each second leaf spring 5 and each support portion 52 are also made of the same metal material as the outer shell member 11.

[0052] [(3) Second leaf spring] Each second leaf spring 5 is a plate-shaped member, and the portions of each second leaf spring 5 that generate a restoring force based on the spring constant are separated from each other. Each second leaf spring 5 has a root portion 50 and two side portions 51 (see FIGS. 6A to 6C).

[0053] The base portion 50 is an elongated portion that extends substantially linearly along the extension direction, and is, for example, plate-shaped. Both ends of the base portion 50 in the extension direction are connected to the support portions 52, respectively. The two side portions 51 are, for example, substantially rectangular plate-shaped portions that protrude from both ends of the base portion 50 in the width direction perpendicular to the extension direction. Specifically, the end forming the long side of each side portion 51 is connected to the base portion 50. Hereinafter, the end of each side portion 51 opposite the base portion 50 will be referred to as the tip portion 51A. The tip portion 51A corresponds to the long side of the side portion 51 and extends substantially linearly. The tip portions 51A of the two side portions 51 extend substantially parallel to each other.

[0054] That is, the second leaf spring 5 has a groove protruding in the thickness direction T, and the cross section perpendicular to the extension direction of the base portion 50 is, for example, substantially V-shaped. Of course, the shape of the cross section is not limited to this, and may be, for example, substantially U-shaped.

[0055] [(4) Support part] The support portions 52 are rod-shaped portions that extend substantially linearly, extend along a first reference plane R1, which is an imaginary plane that is substantially parallel to the first and second wall portions 12, 13, and are arranged substantially parallel to each other at substantially equal intervals (see FIGS. 6A to 6C). As an example, the support portions 52 extend along the longitudinal direction L and are arranged side by side along the lateral direction S. However, the present invention is not limited to this, and the support portions 52 may also extend along the lateral direction S and be arranged side by side along the longitudinal direction L.

[0056] [(5) Placement of the second leaf spring] The second leaf springs 5 ​​are arranged in a matrix across the entire heat exchange medium flow path 16 (see FIGS. 6A to 6C). As an example, three rows of second leaf springs 5 ​​extending in the longitudinal direction L are formed in the flow path 16. These rows are aligned along the short-side direction S, with a row of second leaf springs 5 ​​arranged between adjacent support portions 52. The second leaf springs 5 ​​in each row are aligned along the short-side direction S with the second leaf springs 5 ​​in the adjacent row.

[0057] In addition, each second leaf spring 5 is arranged so that the extension direction of the root portion 50 is approximately perpendicular to the support portion 52, in other words, so that the extension direction is approximately aligned with the short direction S, and both ends of the extension direction of the root portion 50 are connected to the support portion 52.

[0058] Each support portion 52 and the root portion 50 of each second leaf spring 5 extend along the first reference plane R1. The tip portion 51A of each side portion 51 of each second leaf spring 5 extends along a second reference plane R2, which is an imaginary plane substantially parallel to the first reference plane R1 and is provided for that second leaf spring 5. The height H of each groove-shaped second leaf spring 5 is the distance between the first reference plane R1 and the second reference plane R2 corresponding to that second leaf spring 5. The height H of each second leaf spring 5 is substantially uniform. The height H (i.e., the shape) of each second leaf spring 5 is uniquely determined, and the height H of each second leaf spring 5 may not coincide with the height H of other second leaf springs 5.

[0059] Furthermore, the spring constants of the second leaf springs 5 ​​when a force is applied in the direction of height H (hereinafter simply referred to as spring constants) are, for example, substantially uniform. Furthermore, the spring constants of the second leaf springs 5 ​​are, for example, substantially the same.

[0060] Each support portion 52 is located on the first wall portion 12 side, and the tip portion 51A of each second leaf spring 5 is located on the second wall portion 13 side. Similarly to the first embodiment, each second leaf spring 5 and each support portion 52 is disposed in the flow path 16 without being fixed to the outer shell member 11. Therefore, in the second embodiment, a generated distance similar to that in the first embodiment occurs. The generated distance is determined by the height H of the second leaf spring 5 located near the pressing portion of the first or second wall portion 12, 13.

[0061] [(6) Distribution of occurrence distance] As in the first embodiment, the cushioning member 2 of the second embodiment is configured so that the generated distance becomes longer along the longitudinal direction L toward the center C, and also becomes longer along the lateral direction S toward the center C (see Figures 6A to 6C).

[0062] Each of the first and second wall portions 12, 13 has a plurality of blocks B, each of which is substantially rectangular (see FIG. 7A). In the second embodiment, the blocks B are rectangular regions located in front of each row of second leaf springs 5 ​​extending in the longitudinal direction L. Each block B extends from near one end to near the other end in the lateral direction S of the row of second leaf springs 5 ​​located in front of it, and also extends from one end to the other end in the longitudinal direction L of the first or second wall portion 12, 13. The blocks B are lined up adjacent to each other along the lateral direction S and are arranged across the entire area of ​​each of the first and second wall portions 12, 13.

[0063] As described above, in the flow path 16, rows of second leaf springs 5 ​​extending along the longitudinal direction L are formed, and in each row, the height H of the second leaf springs 5 ​​decreases toward the central portion C. Therefore, in each block B, the generated distance is distributed so that it increases toward the central portion C along the longitudinal direction L. Note that the buffer member 2 may have a portion where the generated distance is gradually increased toward the central portion C along the longitudinal direction L, and a portion where the generated distance is increased in stages. Alternatively, the buffer member 2 may have a portion where the generated distance is gradually or staged increased toward the central portion C along the longitudinal direction L.

[0064] As described above, the second leaf springs 5 ​​have a constant height H, and the root portion 50 and each tip portion 51A extend along the short-side direction S. In the flow path 16, three second leaf springs 5 ​​are arranged side by side along the short-side direction S, but the height H of the central second leaf spring 5 is lower than the height H of the second leaf springs 5 ​​at both ends.

[0065] Therefore, in each block B, the generation distance is distributed approximately uniformly along the short-side direction S. At each position in the long-side direction L, the generation distance of the central block B is longer than the generation distance of the blocks B at both ends. In other words, in the cushioning material 2, the generation distance is distributed so that it gradually increases along the short-side direction S toward the center C. Of course, this is not a limitation, and in the cushioning material 2, the generation distance may be distributed so that it gradually increases along the short-side direction S toward the center C.

[0066] [(7) Modification] In the second embodiment, the spring constants of the second leaf springs 5 ​​are approximately the same, and the spring constants are distributed approximately uniformly throughout the cushioning member 2. However, in a cushioning member 2 according to a modification of the second embodiment, each second leaf spring 5 is provided with its own spring constant (in other words, restoring force) by adjusting, for example, the plate thickness or the shape of the side portions 51. The cushioning member 2 is configured so that the spring constant decreases toward the center C along the longitudinal direction L, and also decreases toward the center C along the lateral direction S.

[0067] Specifically, in each row of second leaf springs 5 ​​extending in the longitudinal direction L, the spring constant of the second leaf springs 5 ​​located closer to the center C becomes smaller, and in each row of second leaf springs 5 ​​extending in the lateral direction S, the spring constant of the second leaf springs 5 ​​located closer to the center C becomes smaller.

[0068] In other words, the buffer member 2 is configured so that the spring constant gradually decreases along the longitudinal direction L toward the central portion C, and also so that the spring constant gradually decreases along the lateral direction S toward the central portion C. Of course, this is not limiting, and the buffer member 2 may also be configured so that the spring constant gradually decreases along the longitudinal direction L and the lateral direction S toward the central portion C.

[0069] Furthermore, while the spring constant of each second leaf spring 5 is set as described above, the buffer member 2 may be configured so that the generated distance is approximately uniform. In other words, the height H of each second leaf spring 5 may be approximately the same (see FIG. 7B).

[0070] In the second embodiment, the orientations of all second leaf springs 5 ​​are adjusted so that the extension direction of the root portions 50 substantially coincides with the short-side direction S. However, this is not limiting, and the orientation of each second leaf spring 5 can be adjusted as appropriate. Specifically, as shown in FIG. 8A , most of the second leaf springs 5 ​​may be arranged so that the extension direction of the root portions 50 substantially coincides with the short-side direction S, while some of the second leaf springs 5 ​​may be arranged so that the extension direction of the root portions 50 is inclined with respect to the short-side direction S. This allows the heat exchange medium flowing through the flow paths 16 to be agitated, thereby enabling better heat exchange with the battery cells 4.

[0071] 3. Third Embodiment The third embodiment relates to a buffer member 6 arranged between multiple stacked battery cells 4 (see FIGS. 8B, 9A, and 9B). Each battery cell 4 is configured in the same manner as the battery cell 4 of the first embodiment. The multiple battery cells 4 are stacked so that their main surfaces 40 face each other, and an arrangement space A extending in the longitudinal direction L and the lateral direction S is formed between the main surfaces 40 of adjacent battery cells 4. A buffer member 6 is arranged in each arrangement space A to protect the battery cell 4. Note that a pack member for holding the position of the buffer member 6 may be provided between the multiple stacked battery cells 4 with the buffer member 6 sandwiched therebetween.

[0072] The buffer member 6 of the third embodiment has the same configuration as the buffer member 2 of the first or second embodiment. That is, the buffer member 6 of the third embodiment may have a plurality of first leaf springs 3 configured similarly to the first embodiment or the modified example of the first embodiment (see FIGS. 8B and 9A). These first leaf springs 3 are arranged in the arrangement space A in the same manner as the plurality of first leaf springs 3 are arranged in the flow path 16 of the heat exchanger 10. That is, the plurality of first leaf springs 3 of the buffer member 6 are arranged in the arrangement space A from one end to the other in the longitudinal direction L. Furthermore, each first leaf spring 3 extends from one end to the other in the lateral direction S of the arrangement space A.

[0073] Alternatively, the buffer member 6 of the third embodiment may have a plurality of second leaf springs 5 ​​configured similarly to the second embodiment or the modified example of the second embodiment (see FIGS. 6A and 9B). These second leaf springs 5 ​​are arranged in the arrangement space A in the same manner as the plurality of second leaf springs 5 ​​are arranged in the flow path 16 of the heat exchanger 10. That is, the plurality of second leaf springs 5 ​​of the buffer member 6 are arranged in the arrangement space A in a matrix along the longitudinal direction L and the lateral direction S.

[0074] It goes without saying that the cushioning member 6 has a distribution of generated distances and spring constants similar to the first embodiment, the modified example of the first embodiment, the second embodiment, or the modified example of the second embodiment.

[0075] [4. Effects] (1) When deterioration over time occurs in a flat battery cell 4, the center of each main surface 40 facing each other in the thickness direction may expand, causing the battery cell 4 to deform so that the thickness increases from the edge toward the center, as shown in Fig. 10. In contrast, in the buffer members 2 of the heat exchangers 10 of the first and second embodiments, the expansion distances are distributed so that they increase toward the center C in the longitudinal direction L and the lateral direction S.

[0076] That is, even if the first and second wall portions 12, 13 are deformed due to expansion of the center of each main surface 40 of the battery cell 4, if there is an expansion distance, after the expansion has progressed to a certain extent, the first and second wall portions 12, 13 begin to press against the buffer member 2 from both sides. This applies a restoring force from the buffer member 2 to the first and second wall portions 12, 13, and as a result, the first and second wall portions 12, 13 are pressed against the battery cell 4.

[0077] In contrast, the distance over which the shock absorbers 2 expand increases toward the center C, and as the expansion progresses toward the center C, the shock absorbers 2 deform and begin to generate a restoring force. In other words, even if the center of each main surface 40 of the battery cell 4 expands, the shock absorbers 2 can deform to accommodate this expansion. This prevents localized application of restoring force to the center of the main surface 40, encouraging more uniform compression of the entire main surface 40. This prevents load concentration on the heat exchanger 10 and the battery cells 4, thereby preventing damage to the heat exchanger 10 and the battery cells 4. Furthermore, excessive deformation of the shock absorbers 2 can be prevented, and as a result, plastic deformation of the shock absorbers 2 can be prevented.

[0078] (2) Furthermore, in the buffer member 2 of the modified examples of the first and second embodiments, the spring constant is distributed so that it decreases toward the center C in the longitudinal direction L and the lateral direction S. Therefore, even if the center of each main surface 40 of the battery cell 4 expands and the buffer member 2 is pressed from both sides by the first and second wall portions 12, 13, the first and second wall portions 12, 13 and the buffer member 2 can deform appropriately in response to the expansion. This also prevents excessive restoring force from being generated in the center C of the buffer member 2 and its surroundings.

[0079] In other words, even if the center of each main surface 40 of the battery cell 4 expands, it is possible to prevent a localized restoring force from being applied toward the center of the main surface 40, and promote more uniform pressure across the entire main surface 40. This prevents the concentration of load on the heat exchanger 10 and the battery cells 4, thereby preventing damage to the heat exchanger 10 and the battery cells 4.

[0080] (3) In the first embodiment, by making the grooves of adjacent first leaf springs 3 protrude in different directions (see FIGS. 3A and 3B), it is possible to agitate the heat exchange medium flowing through the flow path 16. This allows for better heat exchange in the battery cells 4. In addition, the pressure applied from the buffer member 2 to the outer shell member 11 can be dispersed, thereby reducing damage to the outer shell member 11 and the battery cells 4.

[0081] (4) In the second embodiment and the modified example of the second embodiment, the buffer member 2 has a plurality of second leaf springs 5 ​​each having a unique height H and spring constant. Therefore, by appropriately arranging the plurality of second leaf springs 5 ​​in the flow path 16, it is possible to appropriately distribute the generated distance and / or the restoring force. Therefore, it is possible to more effectively suppress the concentration of the load.

[0082] (5) In the first and second embodiments, the generated distance is adjusted by the height H of the groove of the first or second leaf spring 3, 5 included in the buffer member 2. This makes it possible to appropriately distribute the generated distance.

[0083] (6) Furthermore, in the cushioning member 6 of the third embodiment, as in the cushioning members 2 of the first and second embodiments, even if the center of each main surface 40 of a battery cell 4 expands, the entire main surface 40 is encouraged to be pressed more uniformly. This prevents the concentration of load on the cushioning member 6 or the battery cell 4, thereby preventing damage to the cushioning member 6 or the battery cell 4.

[0084] 5. Other Embodiments (1) In the first embodiment, the buffer member 2 has a plurality of first leaf springs 3, but the buffer member 2 may be composed of a single leaf spring. In the first embodiment, for example, the number of first leaf springs, the number of grooves in each first leaf spring, the extending direction of the grooves, and the protruding direction of the grooves can be determined appropriately depending on the distribution of the generated distance and spring constant in the buffer member 2.

[0085] Also in the second embodiment, for example, the number of second leaf springs, the orientation of the root portion 50, and the direction in which the side portion 51 protrudes from the root portion 50 can be determined appropriately depending on the distribution of the generation distance and spring constant in the buffer member 2.

[0086] (2) In the first embodiment, a plurality of first leaf springs 3 are arranged side by side along the longitudinal direction L. However, this is not limiting, and in the first embodiment, while the generated distance and spring constant are similarly determined, for example, a plurality of first leaf springs 3 may be arranged side by side along the transverse direction S, or a plurality of first leaf springs may be arranged side by side along both the longitudinal direction L and the transverse direction S.

[0087] (3) In addition, in the buffer member 2 of the second embodiment, other springs (for example, coil springs) may be arranged instead of the second leaf springs 5. In this case, the length of the coil springs corresponds to the height H of the second leaf springs 5, and the length of each coil spring may be adjusted to be the same as the height H of the second leaf springs 5, thereby distributing the generated distance of the buffer member 2.

[0088] The first leaf spring 3 and the second leaf spring 5 included in the buffer member 2 may be made of a material other than metal. Furthermore, the buffer member 2 may have an elastic member made of resin or the like instead of a spring. Even in such a case, the buffer member 2 is configured to distribute the generated distance in the same manner, and to distribute the restoring force in the same manner as the buffer members 2 of the first and second embodiments.

[0089] (4) In the first to third embodiments, the cushioning members 2, 6 have an occurrence distance that increases toward the center C along the longitudinal direction L, and an occurrence distance that increases toward the center C along the lateral direction S. However, this is not limiting, and the cushioning members 2, 6 may be configured so that the occurrence distance increases toward the center C only along the longitudinal direction L or the lateral direction S, and the distribution of the occurrence distance along the lateral direction S or the longitudinal direction L may be determined arbitrarily.

[0090] Furthermore, in the modified examples of the first and second embodiments or the third embodiment, the spring constant of the buffer members 2, 6 decreases toward the central portion C along the longitudinal direction L, and also decreases toward the central portion C along the lateral direction S. However, this is not limiting, and the buffer members 2, 6 are configured so that the spring constant decreases toward the central portion C only along the longitudinal direction L or the lateral direction S, and the distribution of the spring constant along the lateral direction S or the longitudinal direction L may be determined arbitrarily.

[0091] (5) Multiple functions of one component in the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments. [Explanation of symbols]

[0092] 1...heat exchange system, 10...heat exchanger, 11...outer shell member, 12...first wall portion, 13...second wall portion, 14...side wall portion, 15...end portion, 16...flow path, 17...inlet portion, 18...outlet portion, B...block, L...longitudinal direction, S...transverse direction, T...thickness direction, 2...buffer member, C...central portion, 3...first leaf spring, 30...main body portion, 31...middle groove portion, 31A...bottom portion, 32...end groove portion, 32A...bottom portion, H...height of groove portion, 4...battery cell, 40...main surface, 5...second leaf spring, 50...root portion, 51...side portion, 51A...tip portion, 52...support portion, R1...first reference surface, R2...second reference surface, 6...buffer member, A...arrangement space.

Claims

1. A heat exchanger configured to exchange heat with a battery cell, an outer shell member having a flow path for a heat exchange medium provided therein; an elastic buffer member disposed in the flow path of the heat exchange medium; the outer shell member has a first wall portion extending in a substantially planar shape and a second wall portion which faces the first wall portion in a facing direction across the heat exchange medium flow path and extends substantially parallel to the first wall portion, the outer shell member being configured to abut against the battery cells at the first and / or second wall portions; the buffer member is disposed along the first and second wall portions, and configured such that a generating distance becomes longer toward a center portion along a first direction and / or a restoring force becomes lower toward the center portion along the first direction, the first direction is a direction substantially parallel to the first and second wall portions, The generating distance is a distance that a part of the first or second wall portion needs to be displaced in the facing direction in order to generate a restoring force of the buffer member. heat exchanger.

2. 2. The heat exchanger of claim 1, The buffer member is configured such that the generation distance becomes longer toward the center portion along the first direction. heat exchanger.

3. 2. The heat exchanger of claim 1, the buffer member is configured such that the generated distance becomes longer along the first direction toward the central portion and the generated distance becomes longer along the second direction toward the central portion, and / or the restoring force becomes lower along the first direction toward the central portion and the restoring force becomes lower along the second direction toward the central portion, The second direction is a direction that is substantially parallel to the first and second wall portions and is substantially perpendicular to the first direction. heat exchanger.

4. A heat exchanger according to any one of claims 1 to 3, the buffer member has a plurality of first leaf springs arranged along the first and second wall portions, Each of the plurality of first leaf springs has a main body portion and at least one groove portion protruding from the main body portion along the facing direction, each of the plurality of first leaf springs is arranged to extend along the first and second wall portions; The at least one groove in one of two adjacent first leaf springs protrudes toward the first wall portion, and the at least one groove in the other of the adjacent first leaf springs protrudes toward the second wall portion. heat exchanger.

5. A heat exchanger according to any one of claims 1 to 3, the buffer member has a plurality of second leaf springs arranged side by side along the first and second wall portions, Each of the plurality of second leaf springs has a unique shape and / or a unique restoring force, and has a root portion and two side portions protruding from the root portion. heat exchanger.

6. 2. The heat exchanger of claim 1, The buffer member is configured as a leaf spring and has a plurality of grooves protruding in the facing direction, The plurality of grooves are aligned along the first direction, The buffer member is configured such that the height of the groove portion decreases toward the center portion along the first direction, and the generation distance increases toward the center portion along the first direction. heat exchanger.

7. A buffer member configured to be disposed facing a main surface of a battery cell that extends in a substantially planar shape, the buffer member is disposed along the main surface, and configured such that a generating distance becomes longer toward a center portion along a first direction and / or a restoring force becomes lower toward the center portion along the first direction, the first direction is a direction substantially parallel to the main surface, The generating distance is a distance that each portion of the main surface needs to be displaced in a direction substantially perpendicular to the main surface in order to generate a restoring force of the buffer member. Cushioning material.

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