Battery module

Abstract

To provide a battery module capable of reducing a size of a device scale as well as improving a cooling function of a battery cell while securing a binding function of the battery cell.SOLUTION: A battery module comprises: a housing having a housing space where a plurality of battery cells are housed arranged in a lamination state; and a plurality of separation boards provided in the housing so as to separate the housing space for each battery cell at an interval that sandwiches each of the plurality of battery cells in an arrangement direction of the plurality of battery cells. Each of the plurality of separation boards comprises: an elastic body having a hollow projection part that is concaved in a view from the other side in the arrangement direction while being projected to one side in the arrangement direction; and a cooling board that has a higher heat transmission ratio as compared with that of the elastic body, and is bonded with the elastic body so as to cover a cooling path due to the concave of the hollow projection part. The hollow projection part applies a load to each battery cell that is opposite in the arrangement direction, and the cooling board performs a heat exchange between each battery cell and a coolant in the cooling path in contact in the arrangement direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a battery module. [Background technology]

[0002] Conventionally, battery modules have been proposed that include a plurality of battery cells arranged adjacent to each other and constrained in the arrangement direction of the plurality of battery cells. For example, Patent Document 1 discloses a battery module (battery assembly) that includes a plurality of battery cells arranged in a predetermined direction, a buffer plate that is constrained together with the plurality of battery cells in a state in which a load is applied in the arrangement direction, and a cooling plate for cooling the plurality of battery cells.

[0003] In the battery module described in Patent Document 1, the buffer plate has a deformation portion that allows deformation of the battery cell in the thickness direction, and is arranged between the battery cells so as to be in contact with one end surface of the battery cell in the thickness direction. Such a buffer plate absorbs the expansion of the battery cell by deforming the deformation portion in accordance with the expansion of the battery cell in the thickness direction. The internal pressure of the deformation portion of the buffer plate is adjusted by a hydraulic pressure adjustment mechanism, and the load (surface pressure) applied to the battery cell is controlled to be kept constant based on the pressure measured by a pressure sensor between the battery cells. Meanwhile, the cooling plate is arranged between the battery cells so as to be in contact with the other end surface of the battery cell in the thickness direction (the surface opposite to the buffer plate). Such a cooling plate has a refrigerant supply path, and cools the battery cell by heat exchange between the refrigerant flowing through the supply path and the battery cell.

[0004] Patent Document 2 discloses a battery module including a housing that houses a plurality of battery cells arranged in a stacked state in a storage space, and a plurality of partition plates that divide the storage space at intervals that sandwich each of the plurality of battery cells in the arrangement direction. In the battery module described in Patent Document 2, each of the plurality of partition plates includes an action part in which a cooling flow path is formed to allow a refrigerant to flow for cooling the battery cells. The action part is made of a soft resin that can deform in response to the pressure of the refrigerant in the cooling flow path, applies a load to the battery cells in response to the pressure of the refrigerant in the cooling flow path, and cools the battery cells by heat exchange between the battery cells and the refrigerant. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2014-157747 A [Patent Document 2] JP 2022-128335 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the battery module described in the above-mentioned Patent Document 1, in order to ensure both the function of restraining the multiple battery cells with an appropriate load while absorbing deformation in the thickness direction of the battery cells (hereinafter referred to as the restraining function) and the function of cooling the restrained multiple battery cells (hereinafter referred to as the cooling function), it is necessary to arrange separate buffer plates and cooling plates alternately between the multiple battery cells. Therefore, spaces required for arranging the buffer plates and the cooling plates are required between the multiple battery cells, making it difficult to reduce the size of the battery module.

[0007] In recent years, the performance of battery modules has improved, such as by increasing the number and capacity of battery cells housed in a housing, and the amount of heat generated by the battery cells during charging and discharging tends to increase. However, in the battery module described in Patent Document 2 above, it is sometimes difficult to sufficiently cool such battery cells. For this reason, in the field of battery modules, there is a demand for improving the cooling function of the battery cells.

[0008] The present invention has been made in consideration of the above circumstances, and aims to provide a battery module that can improve the cooling function of the battery cells while ensuring the restraint function of the battery cells, and can also reduce the size of the device. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems and achieve the object, a battery module according to the present invention comprises a housing having an accommodation space in which a plurality of battery cells are arranged in a stacked manner, and a plurality of partition plates provided in the housing at intervals that sandwich each of the plurality of battery cells in an arrangement direction of the plurality of battery cells so as to separate the accommodation space for each of the plurality of battery cells, each of the plurality of partition plates comprising: an elastic body having a hollow protrusion that protrudes to one side of the arrangement direction and is recessed when viewed from the other side of the arrangement direction; and a cooling plate having a higher thermal conductivity than the elastic body and joined to the elastic body so as to cover a cooling flow path formed by the recess of the hollow protrusion on the other side of the arrangement direction, the hollow protrusion applying a load to a battery cell of the plurality of battery cells that faces the arrangement direction, and the cooling plate performing heat exchange between a battery cell of the plurality of battery cells that is in contact with the arrangement direction and a refrigerant circulating inside the cooling flow path.

[0010] In addition, the battery module of the present invention is characterized in that, in the above invention, the cooling plate is a metal plate or a resin plate that can deform in response to expansion and contraction of battery cells that are in contact with the battery cells in the arrangement direction among the plurality of battery cells.

[0011] In addition, in the battery module according to the present invention, in the above invention, the battery module further includes a heat insulating material interposed between each of the plurality of battery cells and the elastic body.

[0012] In the battery module according to the present invention, in the above invention, the hollow protrusion is formed so as to extend in a cross direction that crosses the arrangement direction.

[0013] In addition, the battery module according to the present invention is characterized in that, in the above invention, the hollow protrusions are provided on the elastic body so as to be aligned in a direction perpendicular to the arrangement direction and the intersecting direction.

[0014] In addition, the battery module of the present invention, in the above invention, is characterized in that it comprises a pump that sends the refrigerant to the cooling flow path through piping at a variable flow rate, a pressure sensor that detects the pressure between the refrigerant and a battery cell among the plurality of battery cells that faces the hollow protrusion in the arrangement direction, and a control unit that causes the pump to adjust the flow rate of the refrigerant so that the pressure detected by the pressure sensor is within an allowable range for the battery cell to which the load is applied. Effect of the Invention

[0015] The battery module according to the present invention has the advantage that it is possible to improve the cooling function of the battery cells while ensuring the restraining function of the battery cells, and to reduce the size of the device. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a perspective view showing an example of the configuration of a battery pack applied to a battery module according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a top view showing one configuration example of a battery pack applied to the battery module according to the embodiment of the present invention. [Diagram 3] FIG. 3 is a cross-sectional view showing an example of the configuration of the battery pack shown in FIG. 2 taken along line AA. [Figure 4] FIG. 4 is a perspective view showing an example of a configuration of a battery cell in an embodiment of the present invention. [Diagram 5] FIG. 5 is a perspective view showing an example of the configuration of a casing of a battery pack according to an embodiment of the present invention. [Figure 6] FIG. 6 is a top view of the housing shown in FIG. [Figure 7] FIG. 7 is a perspective view showing a configuration example of a partition plate in an embodiment of the present invention. [Figure 8] FIG. 8 is a perspective view showing an example of a configuration of the rear side of the partition plate shown in FIG. [Figure 9] FIG. 9 is a schematic cross-sectional view showing one configuration example of the partition plate shown in FIG. 7 taken along the line BB. [Figure 10] FIG. 10 is a schematic diagram showing an example of a change in state of the partition plate in the embodiment of the present invention. [Figure 11] FIG. 11 is an explanatory diagram illustrating the flow of the refrigerant in the battery pack according to the embodiment of the present invention. [Figure 12] FIG. 12 is a schematic diagram showing a configuration example of a battery module according to an embodiment of the present invention. [Figure 13] FIG. 13 is a flow chart showing an example of the operation of the battery module according to the embodiment of the present invention. [Figure 14] FIG. 14 is a schematic cross-sectional view showing one configuration example of a partition plate according to the first modified example of the present invention. [Figure 15] FIG. 15 is a schematic cross-sectional view showing a configuration example of a partition plate according to the second modification of the present invention. [Figure 16] FIG. 16 is a schematic cross-sectional view showing a configuration example of a partition plate according to the third modified example of the present invention. [Figure 17] FIG. 17 is a schematic cross-sectional view showing one configuration example of a partition plate according to the fourth modified example of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a preferred embodiment of the battery module according to the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to this embodiment. It should be noted that the drawings are schematic, and the dimensional relationship between elements, the ratio of elements, and the like may differ from the actual ones. The drawings may also include parts with different dimensional relationships and ratios. In addition, the same components are denoted by the same reference numerals in each drawing.

[0018] (Battery pack) First, the configuration of a battery pack applied to a battery module according to an embodiment of the present invention will be described. FIG. 1 is a perspective view showing an example of a configuration of a battery pack applied to a battery module according to an embodiment of the present invention. FIG. 2 is a top view showing an example of a configuration of a battery pack applied to a battery module according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing an example of a configuration of the battery pack taken along line AA of FIG. 2. As shown in FIGS. 1 to 3, a battery pack 10 according to this embodiment includes a plurality of battery cells 11, a housing 20 that houses the plurality of battery cells 11, and a plurality of partition plates 30 that divide a housing space 28 of the housing 20. As shown in FIGS. 1 to 3, the battery pack 10 includes a heat insulating material 39 for suppressing heat conduction between the plurality of battery cells 11, an inlet pipe 41 and an inlet branch pipe 42 for introducing a refrigerant for cooling the plurality of battery cells 11 into the housing 20, and an outlet junction pipe 43 and an outlet pipe 44 for leading the refrigerant used for cooling the plurality of battery cells 11 to the outside of the housing 20.

[0019] As shown in Figs. 1 and 2, the multiple battery cells 11 are arranged in a stacked manner and housed in the housing space 28 of the housing 20. In this embodiment, for example, as shown in Figs. 1 and 2, four rows of battery cell groups 11-1 to 11-4 are housed in the housing space 28 of the housing 20. Each of these battery cell groups 11-1 to 11-4 is formed by a multiple battery cells 11 arranged in a stacked manner. For example, each of the battery cell groups 11-1 to 11-4 includes 26 battery cells 11. In this case, the total number of battery cells 11 housed in the housing space 28 is 104. It should be noted that the number of battery cells 11 does not limit the present invention.

[0020] FIG. 4 is a perspective view showing an example of a configuration of a battery cell in an embodiment of the present invention. As shown in FIG. 4, the battery cell 11 includes an outer case 12, a lid portion 16, and a pair of electrode terminals 17, 18. The outer case 12 is a bottomed box-shaped body having abdominal surface portions 13a, 13b, side surface portions 14a, 14b, and a bottom portion 15, and houses the internal electrodes, separators, and the like (not shown) that constitute the battery cell 11. In this outer case 12, the abdominal surface portions 13a, 13b are end surface portions that face the thickness direction of the battery cell 11, and the side surface portions 14a, 14b are end surface portions that face the width direction of the battery cell 11. The areas of the abdominal surface portions 13a, 13b are larger than those of the side surface portions 14a, 14b and the bottom portion 15. The lid portion 16 is attached to an opening of the outer case 12 by welding or the like to close the opening. The lid portion 16 is provided with a pair of electrode terminals 17, 18. For example, one of the pair of electrode terminals 17, 18 is a positive terminal and the other is a negative terminal. Examples of materials that can be used to form the exterior case 12, the lid portion 16, and the electrode terminals 17, 18 include metals such as aluminum.

[0021] As shown in Figs. 1 to 3, such battery cells 11 are arranged so that abdominal surface portions 13a, 13b face each other in the thickness direction of the battery cells 11, and are accommodated in the accommodation space 28 of the housing 20. That is, the arrangement direction D1 of the stacked battery cells 11 is the arrangement direction (stacking direction) of the battery cells 11 in each of, for example, four rows of battery cell groups 11-1 to 11-4, and is the same as the thickness direction of the battery cells 11. In addition, in this embodiment, the width direction D2 of the assembled battery 10 is the same as the width direction of the battery cells 11 in a state accommodated in the housing 20. The above-mentioned battery cell groups 11-1 to 11-4 are accommodated so that the battery cells 11 are arranged adjacent to each other in the width direction D2, as shown in Figs. 1 and 2, for example. The height direction D3 of the assembled battery 10 is a direction perpendicular to the arrangement direction D1 and the width direction D2, and is the same as the height direction of the battery cells 11 in a state accommodated in the housing 20, for example.

[0022] The above-mentioned arrangement direction D1, width direction D2, and height direction D3 are the same for each component of the battery pack 10. For convenience of explanation, the positive side of the arrangement direction D1 may be referred to as the front side or front side, and the negative side of the arrangement direction D1 may be referred to as the rear side or back side. The positive side of the width direction D2 may be referred to as the right side, and the negative side of the width direction D2 may be referred to as the left side. The positive side of the height direction D3 may be referred to as the upper side, and the negative side of the height direction D3 may be referred to as the lower side. These front-rear (front-rear), left-right, and up-down directions do not limit the present invention.

[0023] The housing 20 accommodates the multiple battery cells 11. FIG. 5 is a perspective view showing one configuration example of the housing of the battery pack according to the embodiment of the present invention. FIG. 6 is a top view of the housing shown in FIG. 5. In detail, as shown in FIGS. 5 and 6, the housing 20 has a bottom 21 and side portions 22a, 22b, 22c, and 22d, and is a bottomed box-shaped structure with an open upper side in the height direction D3. The side portions 22a and 22b are a pair of side portions facing each other in the arrangement direction D1 of the multiple battery cells 11. Of these side portions 22a and 22b, the one side portion 22a is provided at one end of the bottom portion 21 in the arrangement direction D1, and the other side portion 22b is provided at the other end of the bottom portion 21 in the arrangement direction D1. The side portions 22c and 22d are a pair of side portions facing each other in the width direction D2 of the multiple battery cells 11. Of these side portions 22c, 22d, one side portion 22c is provided at one end portion of the bottom portion 21 in the width direction D2, and the other side portion 22d is provided at the other end portion of the bottom portion 21 in the width direction D2.

[0024] As shown in FIGS. 5 and 6, the housing 20 includes a plurality of end plates 23a, 23b, 23c, 23d, 23e, 23f, 23g, and 23h, and a plurality of support plates 24a, 24b, 24c, and 24d.

[0025] Specifically, as shown in FIG. 6, the end plates 23a and 23b are disposed at each end of the accommodation chamber group 29-1 in the arrangement direction D1 of the accommodation space 28 of the housing 20, in which the battery cell group 11-1 (see FIGS. 1 and 2) is accommodated. For example, one end plate 23b is erected on the bottom 21 of the housing 20 so as to contact the inner wall surface of the side portion 22b of the housing 20. As a result, the end plate 23b is supported by this side portion 22b. The other end plate 23a is erected on the bottom 21 of the housing 20 so as to face the end plate 23b at a predetermined distance in the arrangement direction D1. This end plate 23a is supported by a support plate 24a described later. These end plates 23a and 23b fix the battery cell group 11-1 accommodated in the accommodation chamber group 29-1 of the housing 20 in a state in which they are sandwiched in the arrangement direction D1.

[0026] As shown in FIG. 6, the end plates 23c and 23d are disposed at each end of the housing chamber group 29-2 in the arrangement direction D1, in which the battery cell group 11-2 (see FIGS. 1 and 2) is housed, in the housing space 28 of the housing 20. For example, the end plate 23d is erected on the bottom 21 so as to contact the inner wall surface of the side portion 22b of the housing 20, similar to the end plate 23b described above, and is thereby supported by the side portion 22b. The other end plate 23c is erected on the bottom 21 of the housing 20 so as to face the end plate 23d at a predetermined distance in the arrangement direction D1. The end plate 23c is supported by a support plate 24b described later. These end plates 23c and 23d fix the battery cell group 11-2 housed in the housing chamber group 29-2 of the housing 20 in a state in which they are sandwiched in the arrangement direction D1.

[0027] As shown in FIG. 6, the end plates 23e and 23f are disposed at each end of the accommodation chamber group 29-3 in the arrangement direction D1 of the accommodation space 28 of the housing 20, in which the battery cell group 11-3 (see FIGS. 1 and 2) is accommodated. For example, one end plate 23f is erected on the bottom 21 so as to contact the inner wall surface of the side portion 22b of the housing 20, similar to the above-mentioned end plates 23b and 23d, and is thereby supported by this side portion 22b. The other end plate 23e is erected on the bottom 21 of the housing 20 so as to face the end plate 23f at a predetermined distance in the arrangement direction D1. This end plate 23e is supported by a support plate 24c described later. These end plates 23e and 23f fix the battery cell group 11-3 accommodated in the accommodation chamber group 29-3 of the housing 20 in a state in which they are sandwiched in the arrangement direction D1.

[0028] As shown in FIG. 6, the end plates 23g and 23h are disposed at each end of the accommodation chamber group 29-4 in the arrangement direction D1 of the accommodation space 28 of the housing 20, in which the battery cell group 11-4 (see FIGS. 1 and 2) is accommodated. For example, one end plate 23h is erected on the bottom 21 so as to contact the inner wall surface of the side portion 22b of the housing 20, similar to the above-mentioned end plates 23b, 23d, and 23f, and is thereby supported by this side portion 22b. The other end plate 23g is erected on the bottom 21 of the housing 20 so as to face the end plate 23h at a predetermined distance in the arrangement direction D1. This end plate 23g is supported by a support plate 24d described later. These end plates 23g and 23h fix the battery cell group 11-4 accommodated in the accommodation chamber group 29-4 of the housing 20 in a state in which they are sandwiched in the arrangement direction D1.

[0029] Of the above-mentioned multiple end plates 23a, 23b, 23c, 23d, 23e, 23f, 23g, and 23h, the front end plates 23a, 23c, 23e, and 23g are preferably arranged to line up with each other in the width direction D2 of the housing 20. Similarly, the rear end plates 23b, 23d, 23f, and 23h are preferably arranged to line up with each other in the width direction D2 along the side portion 22b of the housing 20.

[0030] The plurality of support plates 24a, 24b, 24c, and 24d support the front end plates 23a, 23c, 23e, and 23g, respectively. In detail, as shown in FIG. 6, the support plate 24a is erected on the bottom 21 of the housing 20 so as to contact the front end plate 23a of the pair of end plates 23a and 23b in the housing chamber group 29-1 of the housing 20. The support plate 24a supports the end plate 23a. The support plate 24b is erected on the bottom 21 of the housing 20 so as to contact the front end plate 23c of the pair of end plates 23c and 23d in the housing chamber group 29-2 of the housing 20. The support plate 24b supports the end plate 23c. The support plate 24c is erected on the bottom 21 of the housing 20 so as to contact the front end plate 23e of the pair of end plates 23e, 23f in the housing chamber group 29-3 of the housing 20. The support plate 24c supports this end plate 23e. The support plate 24d is erected on the bottom 21 of the housing 20 so as to contact the front end plate 23g of the pair of end plates 23g, 23h in the housing chamber group 29-4 of the housing 20. The support plate 24d supports this end plate 23g.

[0031] 5, an inlet branch pipe 42, which will be described later, is joined to the support plates 24a, 24b, and 24c described above. These support plates 24a, 24b, and 24c support this inlet branch pipe 42. An outlet junction pipe 43, which will be described later, is joined to the support plates 24b, 24c, and 24d described above. These support plates 24b, 24c, and 24d support this outlet junction pipe 43.

[0032] Housing 20 having the above-mentioned configuration has storage space 28 in which multiple battery cells 11 (see FIGS. 1 and 2) are arranged in a stacked manner, as shown in, for example, Figures 5 and 6. Storage space 28 of housing 20 is an internal space formed by bottom 21 of housing 20, a pair of left and right side portions 22c, 22d, and multiple end plates 23a, 23b, 23c, 23d, 23e, 23f, 23g, and 23h. This storage space 28 is partitioned into individual battery cells 11 by multiple partition plates 30 provided in housing 20. 5 and 6, for example, the accommodation space 28 is divided into a first row of accommodation chambers 29-1 sandwiched in the arrangement direction D1 by a pair of end plates 23a, 23b, a second row of accommodation chambers 29-2 sandwiched in the arrangement direction D1 by a pair of end plates 23c, 23d, a third row of accommodation chambers 29-3 sandwiched in the arrangement direction D1 by a pair of end plates 23e, 23f, and a fourth row of accommodation chambers 29-4 sandwiched in the arrangement direction D1 by a pair of end plates 23g, 23h. Furthermore, each of the four rows of accommodation chambers 29-1 to 29-4 is divided into a plurality of accommodation chambers 29 for each battery cell 11 by a plurality of partition plates 30.

[0033] Examples of the material for the housing 20 include metals and resins. Examples of the metals include aluminum, copper, iron, and alloys. Examples of the alloys include aluminum alloys, copper alloys, and iron alloys. Examples of the resins include polypropylene. Among these, metals are preferable as the material for the housing 20 from the viewpoints of strength and heat dissipation of the housing 20.

[0034] Further, examples of the materials constituting the end plates 23a, 23b, 23c, 23d, 23e, 23f, 23g, and 23h and the support plates 24a, 24b, 24c, and 24d include resins, such as polypropylene, that are harder than the partition plates 30, and metals. Among these, from the viewpoint of bonding with the housing 20, a material similar to that of the housing 20, particularly metals, is preferable.

[0035] The above-mentioned connection between the housing 20 and the end plates 23a, 23b, 23c, 23d, 23e, 23f, 23g, and 23h may be made by welding (fusion), or by a method other than welding, such as screw fastening or insert molding. The same applies to the connection between the housing 20 and the support plates 24a, 24b, 24c, and 24d.

[0036] The multiple partition plates 30 have the functions of dividing the storage space 28 of the housing 20 into individual battery cells 11, cooling each of the multiple battery cells 11 stored in the storage space 28, and constraining these multiple battery cells 11 within the storage space 28.

[0037] 1 to 3, the partition plates 30 are provided in the housing 20 at intervals that sandwich each of the plurality of battery cells 11 in the arrangement direction D1, so as to separate the storage space 28 of the housing 20 into each of the plurality of battery cells 11. For example, the partition plates 30 are arranged in a line in each of the arrangement direction D1 and the width direction D2, and are joined to the housing 20, so as to separate the storage space 28 into each of the battery cells 11 included in the four rows of battery cell groups 11-1 to 11-4. In this embodiment, as shown in FIGS. 5 and 6, the partition plates 30 separate the storage space 28 into storage chambers 29 for the respective battery cells 11 at the above-mentioned intervals in the arrangement direction D1 of the battery cells 11. The storage chamber groups 29-1 to 29-4 shown in FIGS. 5 and 6 each include a plurality of storage chambers 29 that are lined up in the arrangement direction D1, and are adjacent to each other in the width direction D2. Hereinafter, the plurality of partition plates 30 separating the storage chamber group 29-1 may be abbreviated as the partition plates 30 of the storage chamber group 29-1. Similarly, the plurality of partition plates 30 separating the storage chamber groups 29-2 to 29-4 may be abbreviated as the partition plates 30 of the storage chamber group 29-2, the partition plates 30 of the storage chamber group 29-3, and the partition plates 30 of the storage chamber group 29-4.

[0038] For example, in each of the partition plates 30 of the storage chamber group 29-1, one end of the partition plate 30 in the width direction D2 is joined to the side portion 22c of the housing 20, and the other end of the partition plate 30 in the width direction D2 is joined to one end of the partition plate 30 of the adjacent storage chamber group 29-2 in the width direction D2. In each of the partition plates 30 of the storage chamber group 29-2, the other end of the partition plate 30 in the width direction D2 is joined to one end of the partition plate 30 of the adjacent storage chamber group 29-3 in the width direction D2. In each of the partition plates 30 of the storage chamber group 29-3, the other end of the partition plate 30 in the width direction D2 is joined to one end of the partition plate 30 of the adjacent storage chamber group 29-4 in the width direction D2. In each of the partition plates 30 of the storage chamber group 29-4, the other end of the partition plate 30 in the width direction D2 is joined to the side portion 22d of the housing 20. Further, the plurality of partition plates 30 are joined in the arrangement direction D1 at the above-mentioned intervals in each of the storage chamber groups 29-1 to 29-4 via refrigerant flow pipes, which will be described later.

[0039] The joining method between the side ends of the partition plates 30 or between the side ends of the partition plates 30 and the side parts 22c, 22d of the housing 20 may be welding (welding), bonding using an adhesive, or fitting the side parts of the partition plates 30 into recesses (not shown) provided in the side parts 22c, 22d of the housing 20. Alternatively, the joining method may be a combination of two or more of these methods. Also, each of the multiple partition plates 30 may be erected on the bottom part 21 of the housing 20 by joining one end (lower end) of the partition plate 30 in the height direction D3 to the bottom part 21 of the housing 20.

[0040] As shown in FIG. 3, each of the partition plates 30 includes a sheet-like elastic body 31 having a plurality of hollow protrusions 32 that form cooling flow paths 33, which are paths for the coolant to cool the battery cells 11, and a cooling plate 34 having a higher thermal conductivity than the elastic body 31. The hollow protrusions 32 are portions of the elastic body 31 that protrude toward one side of the arrangement direction D1. The cooling flow paths 33 are formed by recesses (grooves) of the hollow protrusions 32 that are recessed when viewed from the other side of the arrangement direction D1, and allow the coolant to flow through the cooling flow paths 33. The cooling plate 34 is joined to the rear side (back side) of the elastic body 31, and closes the openings of the recesses (cooling flow paths 33) of the hollow protrusions 32 in the arrangement direction D1. That is, the cooling plate 34 is in direct contact with the coolant flowing through the inside of the cooling flow paths 33. Details of the configuration of the partition plate 30 will be described later.

[0041] In this partition plate 30, the hollow protrusions 32 expand and contract or scale by utilizing their own elasticity and the pressure of the refrigerant in the cooling flow passages 33. As a result, the hollow protrusions 32 come into direct or indirect contact with the battery cells 11 facing one side in the arrangement direction D1, and apply a load to the battery cells 11. In addition, the cooling plate 34 comes into contact with the battery cells 11 facing the other side in the arrangement direction D1 by utilizing the elasticity of the hollow protrusions 32 and the pressure of the refrigerant. The cooling plate 34 exchanges heat between the battery cells 11 in contact with the refrigerant, thereby cooling the battery cells 11.

[0042] 3, for example, the partition plate 30-1 has the hollow protrusion 32 protruding toward the positive side of the arrangement direction D1 indirectly contacting the abdominal surface portion 13b of the battery cell 11a that faces the elastic body 31 in the same direction via the heat insulating material 39. The hollow protrusion 32 applies a load to the battery cell 11a while absorbing the expansion or contraction deformation of the battery cell 11a in the arrangement direction D1 by utilizing the pressure of the refrigerant in the cooling flow path 33, etc. As a result, the partition plate 30-1 cooperates with the adjacent partition plates 30-3 and the like aligned in the arrangement direction D1 to sandwich the battery cell 11a in the arrangement direction D1, and restrains the battery cell 11a within the storage chamber 29 of the housing 20 with an appropriate load (see FIGS. 5 and 6). At the same time, the partition plate 30-1 brings the cooling plate 34 on the rear side of the elastic body 31 into contact with the battery cell 11b facing the negative side of the arrangement direction D1, and performs heat exchange between this battery cell 11b and the refrigerant in the cooling flow path 33. In this way, the partition plate 30-1 cools the battery cell 11b.

[0043] As shown in FIG. 3, of the battery cells 11a and 11b adjacent to each other in the arrangement direction D1, the cooling of one of the battery cells 11a is performed by the partition plate 30-3 adjacent to the partition plate 30-1 on the positive side of the arrangement direction D1. The cooling method of the battery cell 11a by the partition plate 30-3 is the same as the cooling method of the battery cell 11b by the partition plate 30-1 described above. Moreover, the deformation due to expansion and contraction of the other battery cell 11b is absorbed by the partition plate 30-2 adjacent to the partition plate 30-1 on the negative side of the arrangement direction D1. At the same time, a load is applied to the battery cell 11b by the partition plate 30-2. The action of the partition plate 30-2 on the battery cell 11b is the same as the action of the partition plate 30-1 on the battery cell 11a described above.

[0044] The heat insulating material 39 is a member that suppresses heat conduction between each of the multiple battery cells 11. In particular, the heat insulating material 39 is a sheet-like heat insulating material that is soft enough not to inhibit the action (deformation absorption and load application) of the elastic body 31 of the partition plate 30 on the above-mentioned battery cells 11. The heat insulating material 39 is interposed between each of the multiple battery cells 11 and the elastic body 31, thereby suppressing heat conduction between the battery cells 11.

[0045] For example, as shown in FIG. 3, the heat insulating material 39 is provided at one end of the elastic body 31 of the partition plate 30-1 in the arrangement direction D1 (the end opposite to the cooling plate 34). More specifically, the heat insulating material 39 is joined to the top surface (projecting end surface) of the hollow protrusion 32 formed in the elastic body 31. In this case, the heat insulating material 39 is interposed between the elastic body 31 of the partition plate 30-1 and the battery cell 11a facing the elastic body 31 on the positive side of the arrangement direction D1. The elastic body 31 uses the elasticity of the hollow protrusion 32 and the pressure of the refrigerant in the cooling flow path 33 to bring the heat insulating material 39 into contact with the abdominal surface portion 13b of the battery cell 11a. The heat insulating material 39 blocks heat conduction between the battery cells 11a, 11b adjacent to each other in the arrangement direction D1, for example. As a result, the heat insulating material 39 prevents the heat generated at a high temperature in the event of an abnormality in the battery cell 11a from being transferred to the adjacent battery cell 11b. In particular, even if the battery cell 11a experiences thermal runaway due to overcharging, aging, abnormal usage, or the like, the heat insulating material 39 blocks heat transfer from the thermally runaway battery cell 11a to the adjacent battery cell 11b. This makes it possible to prevent damage to the battery cell 11b due to heat. At the same time, the thermally runaway battery cell 11a is cooled by the cooling plate 34 of the partition plate 30-3 that is in surface contact with the battery cell 11a in the arrangement direction D1. This eliminates the thermal runaway of the battery cell 11a.

[0046] The inlet pipe 41 and the inlet branch pipe 42 are pipes for making the refrigerant flow into each cooling flow passage 33 (see FIG. 3) of the plurality of partition plates 30. In detail, as shown in FIGS. 1, 2, 5, and 6, the inlet pipe 41 is inserted into a through hole formed in the front side portion 22a of the housing 20, and is piped so as to extend along the left side portion 22c and joined to the inlet branch pipe 42. As a result, the inlet pipe 41 communicates with a supply pipe (not shown) that supplies the refrigerant to the battery pack 10 and the inlet branch pipe 42. The inlet branch pipe 42 is piped so as to branch off from the inlet pipe 41, and is joined to the support plates 24a, 24b, and 24c so as to communicate the inlet pipe 41 with each cooling flow passage 33 of the plurality of partition plates 30. For example, as shown in FIG. 5, the inlet branch pipe 42 branches off for each row of the four rows of the storage chamber groups 29-1 to 29-4 and is joined to the inlet of the partition plate 30. The inlet branch pipe 42 causes the refrigerant flowing in from the inlet pipe 41 to flow through the inlets to each of the cooling flow paths 33 of the partition plates 30 for each row of the accommodation chamber groups 29-1 to 29-4.

[0047] The outlet junction pipe 43 and the outlet pipe 44 are pipes for allowing the refrigerant, which has cooled each of the battery cells 11, to flow from each of the cooling passages 33 to the outside of the battery pack 10. In detail, as shown in Figs. 1, 2, 5, and 6, the outlet junction pipe 43 is arranged to connect each of the cooling passages 33 of the partition plates 30 to the outlet pipe 44, and is joined to the support plates 24b, 24c, and 24d. For example, as shown in Fig. 5, the outlet junction pipe 43 is joined to the outlets of the partition plates 30 for each of the four rows of the storage chamber groups 29-1 to 29-4. The outlet junction pipe 43 is joined to the outlet pipe 44 so as to connect the outlets of the partition plates 30 to the outlet pipe 44. The outlet junction pipe 43 allows the refrigerant, which has cooled each of the battery cells 11, to flow from the outlets of the partition plates 30 to the outlet pipe 44. 1, 2, 5, and 6, the outlet pipe 44 is inserted into a through hole formed in the front side portion 22a of the housing 20, and is arranged to extend along the right side portion 22d and joined to the outlet junction pipe 43. In this way, the outlet pipe 44 communicates between an outflow pipe (not shown) outside the battery pack 10 and the outlet junction pipe 43. The outlet pipe 44 allows the refrigerant that has flowed in (joined) from the outlet junction pipe 43 to flow toward the outflow pipe.

[0048] Next, the partition plate 30 in the embodiment of the present invention will be described in detail. FIG. 7 is a perspective view showing one configuration example of the partition plate in the embodiment of the present invention. FIG. 7 shows the partition plate 30 as viewed from the front side (elastic body 31 side). FIG. 8 is a perspective view showing one configuration example of the back side of the partition plate shown in FIG. 7. FIG. 8 shows the partition plate 30 as viewed from the cooling plate 34 side. FIG. 9 is a cross-sectional schematic diagram showing one configuration example of the partition plate shown in FIG. 7 in the cross section of line BB. As shown in FIGS. 7 to 9, the partition plate 30 includes an elastic body 31 having hollow protrusions 32 and cooling flow paths 33, and a cooling plate 34 having a higher thermal conductivity than the elastic body 31.

[0049] 7 and 9, the elastic body 31 is a sheet-like member in which a plurality of hollow protrusions 32 are integrally formed via a base portion 31a. For example, materials constituting the base portion 31a of the elastic body 31 include elastic resins such as olefin-based elastomers or silicone rubber, and low-elasticity resins having lower elasticity than the elastic resins. Examples of the low-elasticity resins include flexible resins.

[0050] As shown in Figs. 7 and 9, the hollow protrusion 32 is a hollow protrusion that protrudes from the base 31a of the elastic body 31 to one side of the arrangement direction D1 (positive side in Figs. 7 and 9) and is recessed to the other side of the arrangement direction D1 (negative side in Figs. 7 and 9). That is, the hollow protrusion 32 is in a protruding state when viewed from one side of the arrangement direction D1 and is recessed when viewed from the other side of the arrangement direction D1. For example, as shown in Fig. 9, the hollow protrusion 32 is formed so that its cross section has a hollow trapezoidal shape tapering from the base 31a side (cooling plate 34 side) toward the positive side (protruding direction) of the arrangement direction D1. Also, as shown in Fig. 7, the hollow protrusion 32 is formed so as to extend in an intersecting direction intersecting with the arrangement direction D1. In this embodiment, the intersecting direction is the same as the width direction D2 of the partition plate 30. As shown in, for example, FIGS. 7 and 9, the hollow protrusions 32 are provided on the elastic body 31 so as to be aligned in a direction perpendicular to the arrangement direction D1 and the intersecting direction (height direction D3 in this embodiment).

[0051] Examples of the material constituting the hollow protrusion 32 include the same elastic or low elastic resin as the above-mentioned base portion 31a, or a resin softer than the base portion 31a. Among them, the material constituting the hollow protrusion 32 is particularly preferably a soft resin that can deform in response to the pressure of the refrigerant in the cooling flow path 33.

[0052] The cooling flow paths 33 are flow paths for circulating the coolant that cools the battery cells 11 described above. In detail, as shown in FIG. 9, the cooling flow paths 33 are formed by recesses in the hollow protrusions 32 on the other side of the arrangement direction D1, and extend in the same direction (intersecting direction) as the hollow protrusions 32. The other side of the arrangement direction D1 referred to here is the opposite side to the protruding direction of the hollow protrusions 32, that is, the rear side of the hollow protrusions 32. For example, the cooling flow paths 33 form rectangular grooves in the cross section of the hollow protrusions 32 shown in FIG. 9. The partition plate 30 has the same number of cooling flow paths 33 as the hollow protrusions 32 on the rear side of the elastic body 31. The cooling flow paths 33 circulate the coolant from one end side to the other end side in the intersecting direction.

[0053] As shown in FIG. 7, the elastic body 31 has hollow ends 35a and 35b on both sides in the width direction D2. Of these hollow ends 35a and 35b, one hollow end 35a is an end on one side (negative side in FIG. 7) of the elastic body 31 in the width direction D2, and is formed to form a concave space on the same side as the cooling flow path 33 formed by the recess of the hollow protrusion 32 described above. The concave space formed by this hollow end 35a leads to the inlet of the cooling flow path 33. The other hollow end 35b is an end on the other side (positive side in FIG. 7) of the elastic body 31 in the width direction D2, and is formed to form a concave space on the same side as the cooling flow path 33, similar to the hollow end 35a. The concave space formed by this hollow end 35b leads to the outlet of the cooling flow path 33.

[0054] As shown in FIG. 7, the elastic body 31 includes an inlet 36a and an outlet 36b. As shown in FIG. 7, the inlet 36a is provided in the elastic body 31 so as to extend from the hollow end 35a described above toward the positive side of the arrangement direction D1. The inlet 36a communicates with the cooling passage 33 through the space of the hollow end 35a described above, and functions as an inlet for the coolant into the cooling passage 33. The outlet 36b is provided in the elastic body 31 so as to extend from the hollow end 35b described above toward the positive side of the arrangement direction D1, as shown in FIG. 7. The outlet 36b communicates with the cooling passage 33 through the space of the hollow end 35b described above, and functions as an outlet for the coolant from the cooling passage 33.

[0055] The cooling plate 34 cools the battery cells 11 by heat exchange between the refrigerant in the cooling flow passage 33 and the battery cells 11. In detail, the cooling plate 34 is made of a material having a higher thermal conductivity than the elastic body 31, and is joined to the elastic body 31 from the back side of the hollow protrusion 32 (the negative side of the arrangement direction D1) as shown in Figs. 8 and 9. As described above, the hollow protrusion 32 protrudes to one side of the arrangement direction D1, and the cooling flow passage 33 is formed by a recess in the hollow protrusion on the other side of the arrangement direction D1. The cooling plate 34 is joined to the elastic body 31 so as to cover such cooling flow passage 33 from the other side of the arrangement direction D1. In this embodiment, the cooling plate 34 is joined to the back side of the elastic body 31 so as to cover each space formed by the hollow ends 35a, 35b of the elastic body 31 together with the above-mentioned cooling flow passage 33. The joining of the cooling plate 34 and the elastic body 31 may be by welding using heat or light, or may be by adhesion using an adhesive. For example, it is preferable to form a fine uneven structure on each of the bonding surfaces between the cooling plate 34 and the elastic body 31, and bond these bonding surfaces together by the anchor effect.

[0056] As shown in FIG. 8, the cooling plate 34 includes communication openings 37a and 37b. As shown in FIG. 8, the communication opening 37a is provided in the cooling plate 34 so as to extend from the cooling plate 34 to the negative side of the arrangement direction D1 at a position aligned with the above-mentioned inlet 36a in the arrangement direction D1. The communication opening 37a communicates with the inlet 36a through the space of the hollow end portion 35a. By joining the inlet 36a and the communication opening 37a of each partition plate 30 facing each other in the arrangement direction D1, a pipe for allowing the refrigerant to flow into each of the multiple partition plates 30 aligned in the arrangement direction D1 is formed. As shown in FIG. 8, the communication opening 37b is provided in the cooling plate 34 so as to extend from the cooling plate 34 to the negative side of the arrangement direction D1 at a position aligned with the above-mentioned outlet 36b (see FIG. 7) in the arrangement direction D1. The communication port 37b communicates with the outlet port 36b through the space of the hollow end portion 35b. By joining the outlet port 36b and the communication port 37b of each of the partition plates 30 facing each other in the arrangement direction D1, a pipeline is formed for causing the refrigerant to flow out from each of the multiple partition plates 30 aligned in the arrangement direction D1.

[0057] Examples of the material for the cooling plate 34 include metals or resins that have excellent thermal conductivity and can be easily deformed by an external force. Specifically, the cooling plate 34 is preferably a metal plate or resin plate that has a higher thermal conductivity than the elastic body 31 and can be deformed following the expansion and contraction of the battery cells that are in contact with the arrangement direction D1 among the multiple battery cells 11 arranged in a stacked manner. Examples of the metal constituting the metal plate include aluminum, copper, iron, and alloys. Examples of the alloy include aluminum alloys containing aluminum, copper alloys containing copper, and iron alloys containing iron. Examples of the resin constituting the resin plate include high thermal conductive resins (such as silicone resins) that are harder than the elastic body 31 and have high thermal conductivity. Among these, it is particularly preferable that the cooling plate 34 is a metal plate.

[0058] In the partition plate 30 having the above-mentioned configuration, the elastic body 31 increases and decreases the reaction force of the hollow protrusion 32 in accordance with the increase and decrease of the pressure of the refrigerant in the cooling flow passage 33. In this embodiment, the reaction force of the hollow protrusion 32 is a force (e.g., elasticity) that pushes back an external force applied to the hollow protrusion 32. When the pressure of the refrigerant in the cooling flow passage 33 is extremely small, such as when no refrigerant is present inside the cooling flow passage 33, such hollow protrusion 32 has almost no reaction force that pushes back an external force and is easily crushed by pressure. In addition, as the pressure of the refrigerant in the cooling flow passage 33 increases, the hollow protrusion 32 increases the reaction force and becomes more elastic, and as the pressure of the refrigerant in the cooling flow passage 33 decreases, the hollow protrusion 32 decreases the reaction force and becomes more elastic. Such a hollow protrusion 32 comes into contact with a battery cell among the multiple battery cells 11 described above that faces the arrangement direction D1, and while deforming in accordance with the expansion and contraction of the battery cell, applies the above-mentioned reaction force corresponding to the combined force of its own elasticity and the pressure of the refrigerant in the cooling flow path 33 as a load to the battery cell.

[0059] 10 is a schematic diagram showing an example of a state change of a partition plate in an embodiment of the present invention. As shown in FIG. 10, the partition plate 30 causes the hollow protrusions 32 to protrude from the base portion 31a of the elastic body 31 due to a reaction force corresponding to a resultant force of the elasticity inherent to the hollow protrusions 32 of the elastic body 31 and the pressure of the refrigerant 80 in the cooling flow passage 33. As a result, the elastic body 31 is in a state where the hollow protrusions 32 contact the battery cells 11a facing each other in the arrangement direction D1 (see FIG. 3) among the above-mentioned multiple battery cells 11 via the insulating material 39 (state S1). In this state S1, the hollow protrusions 32 press the battery cells 11a due to the reaction force that increases with the increase in the pressure of the refrigerant 80, and apply a load equivalent to the reaction force to the battery cells 11a.

[0060] Here, the battery cell 11 expands or contracts due to its charging state and the like. The contraction of the battery cell 11 is a deformation in which the expanded battery cell 11 returns to its pre-expansion state. As shown in FIG. 10, when the battery cell 11a expands, the hollow protrusion 32 receives the expanded battery cell 11a with a reaction force and maintains a contact state with the battery cell 11a due to the pressure of the refrigerant 80 and the like (state S2). In this state S2, the hollow protrusion 32 absorbs the expansion of the battery cell 11a with the reaction force and applies a reaction force (load) corresponding to the pressure of the refrigerant 80 and the like to the battery cell 11a. When the battery cell 11a contracts, the hollow protrusion 32 maintains a contact state with the battery cell 11a by utilizing the pressure of the refrigerant 80 and the like while applying a reaction force to the contracted battery cell 11a. That is, the hollow protrusion 32 changes from state S2 shown in FIG. 10 to state S1. In this state S1, the hollow protrusion 32 absorbs the contraction of the battery cell 11a by a reaction force, and applies a reaction force (load) to the battery cell 11a according to the pressure of the refrigerant 80, etc. As described above, the hollow protrusion 32 repeatedly changes between states S1 and S2 in accordance with the expansion and contraction of the battery cell 11a.

[0061] 10, the partition plate 30 causes the cooling plate 34 on the rear side of the elastic body 31 to come into contact with the battery cell 11b facing the other side of the arrangement direction D1 (the side opposite the hollow protrusion 32) due to the above-mentioned reaction force. In this case, the hollow protrusion 32 also applies a load equivalent to the above-mentioned reaction force to this battery cell 11b. Due to the action of this hollow protrusion 32, the cooling plate 34 maintains a state of contact with this battery cell 11b. In this state S1, the cooling plate 34 exchanges heat between the battery cell 11b in contact with the arrangement direction D1 and the refrigerant 80 flowing inside the cooling flow path 33, thereby cooling the battery cell 11b.

[0062] 10, when the battery cell 11b expands, the cooling plate 34 maintains contact with the battery cell 11b due to the action of the hollow protrusions 32 and deforms (curves) in response to the expansion of the battery cell 11b. In this case, the cooling plate 34 continues to cool the battery cell 11b by heat exchange with the refrigerant 80, as in the case of the state S1. When the battery cell 11b contracts, the cooling plate 34 maintains contact with the battery cell 11b due to the action of the hollow protrusions 32 and deforms in response to the contraction of the battery cell 11b. That is, the cooling plate 34 changes from state S2 to state S1 shown in FIG. 10. Even in this case, the cooling plate 34 continues to cool the battery cell 11b by heat exchange with the refrigerant 80. The cooling plate 34 repeats the change between states S1 and S2 together with the hollow protrusions 32 in response to the expansion and contraction of the battery cell 11b.

[0063] Next, the flow of the refrigerant in the battery pack 10 of this embodiment will be described. Fig. 11 is an explanatory diagram for explaining the flow of the refrigerant in the battery pack in this embodiment of the present invention. Fig. 11 shows a schematic diagram of the battery pack 10 as viewed diagonally from above the front. In Fig. 11, solid arrows typically indicate the flow of the refrigerant 80 flowing into each of the multiple partition plates 30, and dashed arrows typically indicate the flow of the refrigerant 80 flowing out of each of the multiple partition plates 30.

[0064] As shown in FIG. 11, in the battery pack 10, an inflow path for the refrigerant 80 is formed by the inlet pipe 41, the inlet branch pipe 42, and the inlet pipe 38a (in the present embodiment, the inlet pipes 38a-1 to 38a-4). The inflow path is connected to the inlets of the cooling channels 33 (see FIG. 9) of the partition plates 30. The inlet pipe 38a is formed by joining the inlets 36a (see FIG. 7) and the communication ports 37a (see FIG. 8) of the partition plates 30 facing each other in the arrangement direction D1. In addition, as shown in FIG. 11, in the battery pack 10, an outflow path for the refrigerant 80 is formed by the outlet pipe 38b (in the present embodiment, the outlet pipes 38b-1 to 38b-4), the outlet junction pipe 43, and the outlet pipe 44. The outlets of the cooling channels 33 are connected to the outflow path. The outlet pipe 38b is formed by joining the outlets 36b (see FIG. 7) and the communication ports 37b (see FIG. 8) of the partition plates 30 facing each other in the arrangement direction D1. In this embodiment, the refrigerant 80 flows through the battery pack 10 so as to flow sequentially through the inflow path, the cooling channels 33, and the outflow path.

[0065] 11 , the refrigerant 80 flows from the inlet pipe 41 into the inlet branch pipe 42 in the battery pack 10. The refrigerant 80 in the inlet branch pipe 42 branches and flows through the inlet pipe 38a-1 in the partition plate 30 of the housing chamber group 29-1, the inlet pipe 38a-2 in the partition plate 30 of the housing chamber group 29-2, the inlet pipe 38a-3 in the partition plate 30 of the housing chamber group 29-3, and the inlet pipe 38a-4 in the partition plate 30 of the housing chamber group 29-4.

[0066] The refrigerant 80 in the inlet pipe 38a-1 flows from the inlet pipe 38a-1 through the internal space of the hollow end 35a (see FIG. 7) of the partition plate 30 in each of the storage chamber groups 29-1 into each of the cooling channels 33. The refrigerant 80 then flows through each of the cooling channels 33 in one direction from the inlet pipe 38a-1 to the outlet pipe 38b-1 (in FIG. 11, the positive direction from the negative side to the positive side in the width direction D2) to cool each of the battery cells 11 in the storage chamber group 29-1. In parallel with this, the refrigerant 80 in the inlet pipe 38a-2 flows from the inlet pipe 38a-2 into each of the cooling channels 33 of the partition plates 30 of the storage chamber group 29-2 in the same manner as above, and flows through each of the cooling channels 33 in one direction to cool each of the battery cells 11 in the storage chamber group 29-2. As described above, the refrigerant 80 in the inlet pipe 38a-3 flows from the inlet pipe 38a-3 into each cooling flow passage 33 of the partition plate 30 of the accommodation chamber group 29-3, and cools each battery cell 11 in the accommodation chamber group 29-3 while flowing in one direction inside each cooling flow passage 33. As described above, the refrigerant 80 in the inlet pipe 38a-4 flows from the inlet pipe 38a-4 into each cooling flow passage 33 of the partition plate 30 of the accommodation chamber group 29-4, and cools each battery cell 11 in the accommodation chamber group 29-4 while flowing in one direction inside each cooling flow passage 33.

[0067] 11, after cooling each battery cell 11 in the accommodation chamber group 29-1, the refrigerant 80 flows from each cooling flow path 33 through the internal space of the hollow end portion 35b (see FIG. 7) of the partition plate 30 and into the outlet pipe 38b-1. The refrigerant 80 in the outlet pipe 38b-1 merges with the refrigerant 80 flowing out from each of the partition plates 30 of the accommodation chamber group 29-1 and flows into the outlet junction pipe 43. In parallel with this, the refrigerant 80 after cooling each battery cell 11 in the accommodation chamber group 29-2 flows from each cooling flow path 33 into the outlet pipe 38b-2, and, as described above, flows into the outlet junction pipe 43 while merging with the refrigerant 80 flowing out from each of the partition plates 30 of the accommodation chamber group 29-2. As described above, the refrigerant 80 after cooling each battery cell 11 in the storage chamber group 29-3 flows from each cooling flow path 33 into the outlet pipe 38b-3, merges with the refrigerant 80 flowing out from each of the partition plates 30 of the storage chamber group 29-3, and flows into the outlet junction pipe 43. As described above, the refrigerant 80 after cooling each battery cell 11 in the storage chamber group 29-4 flows from each cooling flow path 33 into the outlet pipe 38b-4, and flows into the outlet junction pipe 43, while merging with the refrigerant 80 flowing out from each of the partition plates 30 of the storage chamber group 29-4.

[0068] The refrigerant 80 that has flowed (merged) into the outlet junction pipe 43 from the outlet pipes 38b-1 to 38b-4 as described above flows from the outlet junction pipe 43 into the outlet pipe 44. Thereafter, the refrigerant 80 flows through the outlet pipe 44 and flows out from the outlet pipe 44 to the outside of the battery pack 10.

[0069] The coolant 80 is not particularly limited as long as it is a fluid that can flow through each cooling flow passage 33 of the partition plate 30. For example, the coolant 80 may be a liquid such as cooling water or cooling oil, a gas such as cold air, or a mixed fluid of these liquids and gases.

[0070] (Battery module) Next, the configuration of a battery module according to an embodiment of the present invention will be described. Fig. 12 is a schematic diagram showing one configuration example of a battery module according to an embodiment of the present invention. As shown in Fig. 12, a battery module 1 according to an embodiment of the present invention includes the above-mentioned battery pack 10, a pump 61, a pressure sensor 62, an upstream valve 63, a downstream valve 64, and a control unit 68. The battery module 1 also includes piping 70 for allowing a refrigerant 80 to flow in and out of the battery pack 10. The piping 70 is provided with a cooling device 69 for cooling the refrigerant 80.

[0071] 12, a supply pipe 71 is connected to the inlet pipe 41 of the battery pack 10, and an outlet pipe 72 is connected to the outlet pipe 44 of the battery pack 10. The supply pipe 71 communicates between the pump 61 and the inlet pipe 41 of the battery pack 10 via an upstream valve 63. The outlet pipe 72 communicates between the outlet pipe 44 of the battery pack 10 and a cooling device 69 via a downstream valve 64. A circulation pipe 73 is connected to the cooling device 69 and the pump 61, which communicates between them. The supply pipe 71, the outlet pipe 72, and the circulation pipe 73 form piping 70 that forms a circulation path for refrigerant 80 that passes from the pump 61 through the battery pack 10 and the cooling device 69 in this order and returns to the pump 61.

[0072] The pump 61 is constituted by an electric pump or the like, and is provided in the middle of the piping 70 as shown in FIG. 12. For example, the supply pipe 71 is connected to the outlet side of the pump 61, and the circulation pipe 73 is connected to the inlet side of the pump 61. The pump 61 sends out the refrigerant 80 through the piping 70 to the cooling flow passage 33 (see FIG. 3) of the battery pack 10 at a variable flow rate. In detail, the pump 61 generates a constant-direction flow (see the dashed arrow in FIG. 12) of the refrigerant 80 inside the piping 70. That is, the pump 61 sucks the refrigerant 80 through the outlet pipe 72, the circulation pipe 73, etc., and pressure-feeds the refrigerant 80 to the battery pack 10 through the supply pipe 71, etc. At this time, the pump 61 adjusts the flow rate of the refrigerant 80 based on the control by the control unit 68, and sends out the refrigerant 80 at the adjusted flow rate to the battery pack 10.

[0073] The pump 61 is driven by energy (electricity, etc.) from a power source of a moving body or device on which the battery module 1 is mounted. For example, when the battery module 1 is mounted on a vehicle, the pump 61 is driven by energy supplied from the power source of the vehicle. In this case, the pump 61 stops driving when the vehicle is stopped or the like and energy is not being supplied from the power source. As a result, the coolant 80 is no longer supplied from the pump 61 to the battery pack 10.

[0074] The pressure sensor 62 detects the pressure between the battery cells 11 (see FIGS. 1 to 3) in the assembled battery 10 and the refrigerant 80. In detail, as shown in FIG. 12, the pressure sensor 62 is provided, for example, in the middle of the outflow pipe 72 (in this embodiment, at a location near the downstream side of the downstream valve 64). The pressure sensor 62 detects the pressure of the refrigerant 80 flowing out of the assembled battery 10 through the outflow pipe 72, as an example of the pressure between the battery cells 11 in the assembled battery 10 and the refrigerant 80. Here, the pressure of the refrigerant 80 increases and decreases with an increase and decrease in the flow rate of the refrigerant 80 sent to the assembled battery 10 by the pump 61, and in the assembled battery 10, the pressure is applied from the refrigerant 80 in the cooling flow passage 33 to the battery cells 11 via the hollow protrusion 32 (see FIG. 3). The battery cell 11 is one of the multiple battery cells 11 in the assembled battery 10 that faces the hollow protrusion 32 in the arrangement direction D1. Each time the pressure sensor 62 detects such a pressure of the refrigerant 80, it transmits an electrical signal indicative of the detected pressure to the control unit 68.

[0075] The upstream valve 63 and the downstream valve 64 are valves for maintaining the pressure of the refrigerant 80 in each cooling flow passage 33 of the battery pack 10 in a state in which the refrigerant 80 is not supplied to the battery pack 10. In detail, as shown in FIG. 12, the upstream valve 63 is provided in a middle part of a supply pipe 71 leading to the inlet pipe 41 of the battery pack 10, for example, a part between the inlet pipe 41 of the battery pack 10 and the pump 61. In this embodiment, the supply pipe 71 is a pipe upstream of the cooling flow passage 33 of the battery pack 10 in the flow direction of the refrigerant 80. In addition, the downstream valve 64 is provided in a middle part of an outlet pipe 72 leading to the outlet pipe 44 of the battery pack 10, for example, near the downstream side of the outlet pipe 44 of the battery pack 10. In this embodiment, the outlet pipe 72 is a pipe downstream of the cooling flow passage 33 of the battery pack 10 in the flow direction of the refrigerant 80.

[0076] The upstream valve 63 and the downstream valve 64 are both open when the refrigerant 80 is being circulated by the pump 61. On the other hand, when the flow of the refrigerant 80 is stopped by stopping the operation of the pump 61, the upstream valve 63 and the downstream valve 64 are both closed. As a result, the upstream valve 63 and the downstream valve 64 prevent the outflow of the refrigerant 80 from the battery pack 10, and maintain the pressure of the refrigerant 80 in each cooling flow path 33 in the battery pack 10.

[0077] The control unit 68 controls each component of the battery module 1. In detail, the control unit 68 is configured with a memory, a CPU, etc., and controls the operation of each of the pump 61, the upstream valve 63, and the downstream valve 64 described above.

[0078] For example, the control unit 68 causes the pump 61 to adjust the flow rate of the refrigerant 80 so that the pressure detected by the pressure sensor 62 falls within a range acceptable for the battery cells 11 of the battery pack 10. In this embodiment, the pressure range acceptable for the battery cells 11 of the battery pack 10 is set by upper and lower limits of the pressure between the refrigerant 80 in the cooling flow passage 33 of the battery pack 10 and the battery cells 11. The upper limit of the pressure is the maximum pressure of the refrigerant 80 that satisfies both the first and second conditions below. The first condition is that the exterior case 12 (see FIG. 4 ) and the internal electrode (not shown) of the battery cells 11 in the battery pack 10 are kept in contact with each other. The second condition is that the battery cells 11 in the battery pack 10 are not damaged. On the other hand, the lower limit of the pressure is the minimum pressure of the refrigerant 80 when the hollow protrusion 32 of the partition plate 30 in the battery pack 10 restrains the battery cells 11 by the pressure of the refrigerant 80 in the cooling flow passage 33. These upper and lower limits of the pressure of the refrigerant 80 can be derived, for example, by experiments, simulations, or the like.

[0079] Furthermore, the control unit 68 monitors the operating state of the pump 61 continuously or intermittently at predetermined intervals, and when the pump 61 is stopped, controls the upstream valve 63 and the downstream valve 64 to be closed. On the other hand, when the pump 61 is operating, the control unit 68 controls the upstream valve 63 and the downstream valve 64 to be opened.

[0080] The cooling device 69 cools the refrigerant 80 used to cool the battery cells 11 in the battery pack 10. In detail, as shown in FIG. 12, the cooling device 69 is provided in the middle of the piping 70. For example, an outlet pipe 72 is connected to the inlet side of the cooling device 69, and a circulation pipe 73 is connected to the outlet side of the cooling device 69. The cooling device 69 recovers the used refrigerant 80 from the outlet pipe 44 of the battery pack 10 through the outlet pipe 72, and cools the recovered refrigerant 80. The refrigerant 80 cooled by the cooling device 69 is sucked into the pump 61 through the circulation pipe 73, and is again pressure-fed from the pump 61 to the battery pack 10 through the supply pipe 71. The cooling device 69 may be used in common with an air conditioner for air conditioning.

[0081] Next, the operation of the battery module 1 according to the embodiment of the present invention will be described. Fig. 13 is a flow diagram showing an example of the operation of the battery module according to the embodiment of the present invention. In order to ensure both the restraining function and the cooling function for the multiple battery cells 11 housed in the casing 20, the battery module 1 appropriately executes each process of steps S101 to S107 shown in Fig. 13.

[0082] 13, the battery module 1 detects the pressure between the battery cells 11 and the refrigerant 80 in the assembled battery 10 (step S101). In step S101, the pressure sensor 62 measures the pressure of the refrigerant 80 in the outflow pipe 72 leading to the outlet pipe 44 of the assembled battery 10 as the pressure between the battery cells 11 and the refrigerant 80. In this embodiment, the pressure of the refrigerant 80 in the outflow pipe 72 is the pressure of the refrigerant 80 that is pumped from the pump 61, flows through the assembled battery 10, and then flows out of the assembled battery 10. In the assembled battery 10, the pressure of the refrigerant 80 generates a reaction force (load) that the hollow protrusions 32 of the partition plate 30 apply to the battery cells 11. The pressure sensor 62 detects the pressure of the refrigerant 80 and transmits an electric signal indicating the detected pressure to the control unit 68.

[0083] After executing step S101, the battery module 1 judges whether or not the detected pressure (hereinafter referred to as pressure P) is within the range of pressure allowed for the battery cells 11 of the battery pack 10 (step S102). In step S102, the control unit 68 receives an electrical signal from the pressure sensor 62, and acquires the pressure indicated in the received electrical signal, i.e., the pressure P of the refrigerant 80 detected by the pressure sensor 62. Next, the control unit 68 calculates a pressure P of the refrigerant 80 and an upper reference value P for the pressure P. H and the lower reference value P L Compare with.

[0084] Here, the upper reference value P H and the lower reference value P L is a reference value for determining whether the pressure P of the refrigerant 80 is within a range permitted for the battery cell 11 (hereinafter referred to as the pressure tolerance range), and is preset in the control unit 68. For example, the upper reference value PH is the lower reference value P L The upper limit of the pressure tolerance range of battery cell 11 is P max Within the range of less than (P L <P H <P max The lower reference value P L is the lower limit of the pressure tolerance range P min Above, upper reference value P H Within the range of less than (P min <P L <P H The control unit 68 determines the pressure P and the upper reference value P H and the lower reference value P L and thereby judges whether the pressure P is within the allowable pressure range of the battery cell 11.

[0085] In step S102, the pressure P of the refrigerant 80 is set to the upper reference value P H If P≧P H ), the battery module 1 reduces the flow rate of the coolant 80 supplied to the battery pack 10 (step S103). In step S103, the control unit 68 controls the pump 61 to reduce the flow rate of the coolant 80. The pump 61 reduces the flow rate of the coolant 80 based on the control by the control unit 68, and pumps the coolant 80 after the flow rate reduction to the battery pack 10 through the supply pipe 71. As a result, the coolant 80 after the flow rate reduction flows from the inlet pipe 41 into the battery pack 10, flows through the cooling flow path 33 of the partition plate 30, and flows out from the outlet pipe 44 to the outflow pipe 72. That is, the flow rate of the coolant 80 in the cooling flow path 33 is adjusted to the flow rate after the reduction by the pump 61. The pressure of the coolant 80 decreases as the flow rate of the coolant 80 decreases.

[0086] Here, the pressure P of the refrigerant 80 is the upper reference value P HIn the above cases, the hollow protrusions 32 of the partition plates 30 in the battery pack 10 are in a state of expanding in a direction pressing against the battery cells 11. Therefore, the load that the hollow protrusions 32 apply to the battery cells 11 in response to the pressure of the refrigerant 80 in the cooling flow paths 33 and the like is increasing so as to approach the upper limit allowable for the battery cells 11. However, the pressure of the refrigerant 80 in the cooling flow paths 33 is reduced in step S103, thereby suppressing the increase in the load. As a result, the load is controlled to a load within the allowable range for the battery cells 11 (preferably a constant load).

[0087] On the other hand, in step S102, the pressure P of the refrigerant 80 is lower than the lower reference value P L Above, upper reference value P H If it is less than (step S102, P L <P<P H ), the battery module 1 maintains the current flow rate of the refrigerant 80 supplied to the battery pack 10 (step S104). In step S104, the control unit 68 controls the pump 61 to maintain the current flow rate of the refrigerant 80. Based on the control by the control unit 68, the pump 61 maintains the flow rate of the refrigerant 80 at the current flow rate, and pumps the refrigerant 80 at this flow rate through the supply pipe 71 to the battery pack 10. As a result, the refrigerant 80 at the above flow rate flows through the battery pack 10 and flows out to the outflow pipe 72, just like in the case of step S103 described above. That is, the flow rate and pressure of the refrigerant 80 in the cooling flow path 33 are maintained at the current levels. Here, when the pressure P of the refrigerant 80 is increased to P L <P<P H In this case, in the battery pack 10 , the load that the hollow protrusion 32 applies to the battery cell 11 in response to the pressure of the coolant 80 in the cooling flow passage 33 and the like is controlled to within the allowable range of the battery cell 11 .

[0088] In step S102, the pressure P of the refrigerant 80 is set to the lower reference value P L If P≦P L), the battery module 1 increases the flow rate of the coolant 80 supplied to the battery pack 10 (step S105). In step S105, the control unit 68 controls the pump 61 to increase the flow rate of the coolant 80. The pump 61 increases the flow rate of the coolant 80 based on the control by the control unit 68, and pumps the coolant 80 after the increased flow rate through the supply pipe 71 to the battery pack 10. As a result, the coolant 80 after the increased flow rate flows through the battery pack 10 and flows out to the outflow pipe 72, similarly to the cases of steps S103 and S104 described above. That is, the flow rate of the coolant 80 in the cooling flow passage 33 is adjusted to the flow rate after the increase by the pump 61. The pressure of the coolant 80 increases with the increase in the flow rate of the coolant 80.

[0089] Here, the pressure P of the refrigerant 80 is the lower reference value P L In the following cases, the battery cells 11 in the battery pack 10 are in a state of expanding in a direction pressing the hollow protrusions 32 of the partition plate 30. That is, the hollow protrusions 32 are crushed by the battery cells 11, and the cooling flow paths 33 are deformed to contract their volume. At this time, the flow rate of the refrigerant 80 in the cooling flow paths 33 decreases, and the pressure P of the refrigerant 80 decreases. Therefore, the load applied to the battery cells 11 by the hollow protrusions 32 according to the pressure of the refrigerant 80 in the cooling flow paths 33 and the like decreases to approach the lower limit allowed for the battery cells 11. However, the pressure of the refrigerant 80 in the cooling flow paths 33 increases in step S105, so that the decrease in the load is suppressed. As a result, the load is controlled to a load (preferably a constant load) within the allowable range of the battery cells 11.

[0090] After executing step S103, step S104, or step S105 described above, the battery module 1 determines whether the pump 61 is in a stopped state (step S106). In step S106, the control unit 68 monitors the operating state of the pump 61, and determines whether the pump 61 is in an operating state or a stopped state based on the monitoring result.

[0091] If the pump 61 is operating (step S106, No), the battery module 1 returns to the above-mentioned step S101 and repeats the processes from step S101 onward. In this case, the upstream valve 63 and the downstream valve 64 are open, and the pump 61 pressure-feeds the refrigerant 80 to the battery pack 10.

[0092] On the other hand, when the pump 61 is stopped (step S106, Yes), the battery module 1 closes the upstream valve 63 and the downstream valve 64 (step S107). In step S107, the control unit 68 controls both the upstream valve 63 and the downstream valve 64 to be closed. The upstream valve 63 switches from an open state to a closed state based on the control by the control unit 68 to close the supply pipe 71. In parallel with this, the downstream valve 64 switches from an open state to a closed state based on the control by the control unit 68 to close the outflow pipe 72. Note that the control unit 68 may control the upstream valve 63 and the downstream valve 64 in order of which valve first, or may control them simultaneously. After executing step S107, the battery module 1 returns to the above-mentioned step S106 and repeats the processes from step S106 onwards.

[0093] As described above, in the battery module 1 according to the embodiment of the present invention, the housing 20 has an accommodation space 28 in which the plurality of battery cells 11 are arranged in a stacked manner, and the plurality of partition plates 30 are provided in the arrangement direction D1 of the plurality of battery cells 11 so as to separate the accommodation space 28 into the respective battery cells 11 at intervals sandwiching the respective battery cells 11. Each of the plurality of partition plates 30 includes an elastic body 31 having a hollow protrusion 32 that protrudes to one side of the arrangement direction D1 and is recessed when viewed from the other side of the arrangement direction D1, and a cooling plate 34 that has a higher thermal conductivity than the elastic body 31 and is joined to the elastic body 31 so as to cover the cooling flow path 33 formed by the recess of the hollow protrusion 32 on the other side of the arrangement direction D1. In this battery module 1, the hollow protrusion 32 applies a load to the battery cells of the plurality of battery cells 11 that face the arrangement direction D1, and in parallel with this, the cooling plate 34 exchanges heat between the battery cells of the plurality of battery cells 11 that are in contact with the arrangement direction D1 and the refrigerant 80 in the cooling flow path 33.

[0094] Therefore, the hollow protrusions 32 that protrude from the front side of the elastic body 31 under the pressure of the refrigerant 80 in the cooling flow passages 33 absorb the expansion or contraction of the battery cells 11 in the thickness direction (arrangement direction D1) while restraining the multiple battery cells 11 in the storage space 28 of the housing 20 with an appropriate load according to the pressure of the refrigerant 80, and each of the multiple battery cells 11 can be cooled by the cooling plate 34 that directly contacts the refrigerant 80 in the cooling flow passages 33 on the back side of the elastic body 31. Therefore, the above-mentioned restraining function and cooling function for the battery cells 11 can be combined in a single component, the partition plate 30, and the arrangement space required for a first component such as a buffer plate that performs the above-mentioned restraining function and the arrangement space required for a second component such as a cooling plate that performs the above-mentioned cooling function can be consolidated into the arrangement space of a single component, the partition plate 30. Furthermore, the cooling plate 34 has superior thermal conductivity compared to the hollow protrusions 32 of the elastic body 31, so that each battery cell 11 can be cooled more efficiently than in the case of heat exchange between the refrigerant 80 and the battery cells 11 via the hollow protrusions 32. As a result, the battery cell cooling function can be improved while maintaining the restraint function of the battery cells, and the device scale of the battery module can be reduced. Furthermore, the cost of the battery module can be reduced.

[0095] Furthermore, the hollow protrusions 32 of the partition plate 30 that act on the battery cells 11 are configured to deform in response to the pressure of the refrigerant 80 in the cooling flow paths 33. Therefore, the elastic body 31 having the hollow protrusions 32 and the cooling flow paths 33 can be formed from a low-elasticity resin, not just a high-elasticity resin. As a result, there is no need to consider the creep of the hollow protrusions 32 when absorbing the expansion or contraction of the battery cells 11, so that an inexpensive elastic resin can be selected as the constituent material of the elastic body 31, which can facilitate cost reduction of the battery module 1.

[0096] Furthermore, in the battery module 1 according to the embodiment of the present invention, the cooling plate 34 described above is made of a metal plate or resin plate that can deform in response to the expansion and contraction of the battery cells 11 that contact it in the arrangement direction D1. Therefore, even if the battery cells expand and contract, the battery cells 11 and the cooling plate 34 can be constantly maintained in surface contact with each other, thereby ensuring high cooling efficiency of the battery cells 11 by the cooling plate 34.

[0097] Furthermore, in the battery module 1 according to the embodiment of the present invention, the pump 61 sends out the refrigerant 80 at a variable flow rate to the cooling flow passage 33 of the partition plate 30 of the assembled battery 10 through the piping 70, the pressure sensor 62 detects the pressure between the refrigerant 80 and the battery cells 11 of the assembled battery 10 (specifically, the battery cells 11 facing the hollow protrusions 32 in the arrangement direction D1), and the control unit 68 causes the pump 61 to adjust the flow rate of the refrigerant 80 so that the pressure P detected by the pressure sensor 62 is within the allowable pressure range of the battery cells 11 of the assembled battery 10. Therefore, before a load applied to the battery cells 11 according to the pressure of the refrigerant 80 in the cooling flow passage 33 from the hollow protrusions 32 of the partition plate 30 exceeds an upper limit of the allowable range of the battery cells 11, the pressure of the refrigerant 80 can be lowered to reduce the load to within the allowable range, and before the load falls below a lower limit of the allowable range of the battery cells 11, the pressure of the refrigerant 80 can be increased to increase the load to within the allowable range. This makes it possible to constantly apply a load within the above-mentioned allowable range to the battery cells 11, and further makes it possible to control the load applied to the battery cells 11 to a constant value within the above-mentioned allowable range.

[0098] (Variation 1) Next, a first modified example of the partition plate 30 included in the battery pack 10 in the embodiment of the present invention will be described. FIG. 14 is a schematic cross-sectional view showing one configuration example of the partition plate according to the first modified example of the present invention. FIG. 14 shows the cross-sectional configuration of the partition plate 30A according to the first modified example, seen from the same viewpoint as the schematic cross-sectional view of the partition plate 30 shown in FIG. 9. As shown in FIG. 14, the partition plate 30A according to the first modified example includes an elastic body 31A instead of the elastic body 31 of the partition plate 30 in the above-mentioned embodiment. The elastic body 31A includes a cooling flow path 33A instead of the cooling flow path 33 in the above-mentioned embodiment. Although not particularly shown, the battery pack according to the first modified example includes the partition plate 30A of the first modified example instead of the partition plate 30 of the above-mentioned embodiment. The battery module according to the first modified example includes the battery pack according to the first modified example instead of the battery pack 10 of the above-mentioned embodiment. The other configurations are the same as those of the above-mentioned embodiment, and the same components are given the same reference numerals.

[0099] As shown in FIG. 14, the cooling flow path 33A is formed by a recess on the back side (the other side of the arrangement direction D1) of the hollow protrusion 32 protruding from the base portion 31a of the elastic body 31A to one side in the arrangement direction D1. In detail, as shown in FIG. 14, the cross section of the cooling flow path 33A in this modified example 1 is trapezoidal in shape tapered toward the protruding direction of the hollow protrusion 32, unlike the rectangular cross section (see FIG. 9) of the cooling flow path 33 in the above-mentioned embodiment. The cooling flow path 33A can pass the refrigerant 80 through it, similarly to the cooling flow path 33 in the above-mentioned embodiment. The constituent material of the elastic body 31A in this modified example 1 is the same as the constituent material of the elastic body 31 in the above-mentioned embodiment.

[0100] The battery module according to the present modified example 1 includes a battery pack provided with the above-described partition plate 30A, and other configurations are the same as those of the above-described embodiment. Therefore, in the present modified example 1, it is possible to provide a battery module that can achieve the same effects as those of the above-described embodiment.

[0101] (Variation 2) Next, a second modification of the partition plate 30 included in the battery pack 10 in the embodiment of the present invention will be described. FIG. 15 is a schematic cross-sectional view showing one configuration example of the partition plate according to the second modification of the present invention. FIG. 15 shows a cross-sectional configuration of the partition plate 30B according to the second modification, seen from the same viewpoint as the schematic cross-sectional view of the partition plate 30 shown in FIG. 9. As shown in FIG. 15, the partition plate 30B according to the second modification includes an elastic body 31B instead of the elastic body 31 of the partition plate 30 in the above-mentioned embodiment. The elastic body 31B includes a hollow protrusion 32B instead of the hollow protrusion 32 in the above-mentioned embodiment. Although not particularly shown, the battery pack according to the second modification includes the partition plate 30B of the second modification instead of the partition plate 30 of the above-mentioned embodiment. The battery module according to the second modification includes the battery pack according to the second modification instead of the battery pack 10 of the above-mentioned embodiment. The other configurations are the same as those of the above-mentioned embodiment, and the same components are given the same reference numerals.

[0102] As shown in Fig. 15, the hollow protrusion 32B is a hollow protrusion that protrudes from the base 31a of the elastic body 31B to one side of the arrangement direction D1 (positive side in this modified example 2) and is recessed on the other side of the arrangement direction D1 (negative side in this modified example 2). Although not particularly shown, the hollow protrusion 32B is formed to extend in a cross direction intersecting the arrangement direction D1 (for example, the same direction as the width direction D2) like the hollow protrusion 32 of the above-mentioned embodiment (see Fig. 7). Also, as shown in Fig. 15, unlike the hollow protrusion 32 (see Fig. 9) having a hollow trapezoidal cross section described above, the hollow protrusion 32B is formed to have a hollow rectangular shape (hollow columnar shape) whose cross section protrudes from the base 31a side (cooling plate 34 side) toward the positive side (protruding direction) of the arrangement direction D1. Like the hollow protrusion 32 in the embodiment described above, this hollow protrusion 32B can act on the battery cell 11 (see FIG. 3) facing it in the arrangement direction D1 by utilizing the pressure of the coolant 80 in the cooling flow passage 33, etc.

[0103] In the present modified example 2, the elastic body 31B preferably has a plurality of hollow protrusions 32B as described above arranged in a direction perpendicular to the arrangement direction D1 and the intersecting direction (for example, the height direction D3) like the hollow protrusions 32 of the elastic body 31 in the above-mentioned embodiment. The constituent material of the elastic body 31B is the same as the constituent material of the elastic body 31 described above.

[0104] The battery module according to the present modified example 2 includes a battery pack provided with the above-described partition plate 30B, and other configurations are the same as those of the above-described embodiment. Therefore, in the present modified example 2, it is possible to provide a battery module that can achieve the same effects as those of the above-described embodiment.

[0105] (Variation 3) Next, a third modification of the partition plate 30 included in the battery pack 10 in the embodiment of the present invention will be described. FIG. 16 is a schematic cross-sectional view showing one configuration example of the partition plate according to the third modification of the present invention. FIG. 16 shows a cross-sectional configuration of the partition plate 30C according to the third modification, seen from the same viewpoint as the schematic cross-sectional view of the partition plate 30 shown in FIG. 9. As shown in FIG. 16, the partition plate 30C according to the third modification includes an elastic body 31C instead of the elastic body 31 of the partition plate 30 in the above-mentioned embodiment. The elastic body 31C includes a hollow protrusion 32C instead of the hollow protrusion 32 in the above-mentioned embodiment. Although not particularly shown, the battery pack according to the third modification includes the partition plate 30C of the third modification instead of the partition plate 30 of the above-mentioned embodiment. The battery module according to the third modification includes the battery pack according to the third modification instead of the battery pack 10 of the above-mentioned embodiment. The other configurations are the same as those of the above-mentioned embodiment, and the same components are given the same reference numerals.

[0106] As shown in FIG. 16, the hollow protrusion 32C is a hollow protrusion that protrudes from the base 31a of the elastic body 31C to one side of the arrangement direction D1 (positive side in this modified example 3) and is recessed to the other side of the arrangement direction D1 (negative side in this modified example 3). Although not particularly shown, the hollow protrusion 32C is formed to extend in a cross direction intersecting with the arrangement direction D1 (for example, the same direction as the width direction D2) like the hollow protrusion 32 of the above-mentioned embodiment (see FIG. 7). Also, as shown in FIG. 16, unlike the hollow protrusion 32 (see FIG. 9) having a hollow trapezoidal cross section described above, the hollow protrusion 32C is formed to have a cross section that combines a hollow trapezoidal shape and a hollow rectangular shape. In detail, as shown in FIG. 16, the hollow protrusion 32C includes an outer protrusion having a hollow trapezoidal cross section and an inner protrusion that is integrally formed inside the outer protrusion and has a hollow rectangular cross section. In the present modified example 3, the cooling flow passage 33 is formed by a recess in the inner protrusion on the back side of the hollow protrusion 32C. Like the hollow protrusion 32 in the above-described embodiment, this hollow protrusion 32C can act on the battery cells 11 (see FIG. 3) facing in the arrangement direction D1 by utilizing the pressure of the refrigerant 80 in the cooling flow passage 33.

[0107] In the present modified example 3, the elastic body 31C preferably includes a plurality of hollow protrusions 32C as described above arranged in a direction perpendicular to the arrangement direction D1 and the intersecting direction (for example, the height direction D3) like the hollow protrusions 32 of the elastic body 31 in the above-mentioned embodiment. The constituent material of the elastic body 31C is the same as the constituent material of the elastic body 31 described above.

[0108] The battery module according to the present modified example 3 includes a battery pack provided with the above-described partition plate 30C, and other configurations are the same as those of the above-described embodiment. Therefore, in the present modified example 3, it is possible to provide a battery module that can achieve the same effects as those of the above-described embodiment.

[0109] (Variation 4) Next, a fourth modification of the partition plate 30 included in the battery pack 10 in the embodiment of the present invention will be described. FIG. 17 is a schematic cross-sectional view showing one configuration example of the partition plate according to the fourth modification of the present invention. FIG. 17 shows a cross-sectional configuration of the partition plate 30D according to the fourth modification, seen from the same viewpoint as the schematic cross-sectional view of the partition plate 30 shown in FIG. 9. As shown in FIG. 17, the partition plate 30D according to the fourth modification includes an elastic body 31D instead of the elastic body 31 of the partition plate 30 in the above-mentioned embodiment. The elastic body 31D includes a hollow protrusion 32D instead of the hollow protrusion 32 in the above-mentioned embodiment, and includes a cooling flow path 33A instead of the cooling flow path 33. Although not particularly shown, the battery pack according to the fourth modification includes the partition plate 30D of the fourth modification instead of the partition plate 30 of the above-mentioned embodiment. The battery module according to the fourth modification includes the battery pack according to the fourth modification instead of the battery pack 10 of the above-mentioned embodiment. The other configurations are the same as those of the above-described embodiment, and the same components are denoted by the same reference numerals.

[0110] As shown in FIG. 17, the hollow protrusion 32D is a hollow protrusion that protrudes from the base 31a of the elastic body 31D to one side of the arrangement direction D1 (positive side in this modified example 4) and is recessed to the other side of the arrangement direction D1 (negative side in this modified example 4). Although not particularly shown, the hollow protrusion 32D is formed to extend in a cross direction intersecting with the arrangement direction D1 (for example, the same direction as the width direction D2) like the hollow protrusion 32 of the above-mentioned embodiment (see FIG. 7). Also, as shown in FIG. 17, unlike the hollow protrusion 32 (see FIG. 9) that has a hollow trapezoidal cross section, the hollow protrusion 32D is formed to have a cross section that combines a hollow trapezoidal shape and a hollow rectangular shape. In detail, as shown in FIG. 17, the hollow protrusion 32D includes an outer protrusion having a hollow rectangular cross section and an inner protrusion that is integrally formed inside the outer protrusion and has a hollow trapezoidal cross section. In the present modification 4, the cooling flow passage 33A is formed by a recess in the inner protrusion on the back side of the hollow protrusion 32D. That is, the cross-sectional shape of the cooling flow passage 33A is a trapezoid that tapers toward the protruding direction of the hollow protrusion 32D, similar to the above-mentioned modification 1. Like the hollow protrusion 32 in the above-mentioned embodiment, this hollow protrusion 32D can act on the battery cells 11 (see FIG. 3) facing in the arrangement direction D1 by utilizing the pressure of the refrigerant 80 in the cooling flow passage 33A, etc.

[0111] In the present modification 4, the elastic body 31D preferably includes a plurality of hollow protrusions 32D as described above arranged in a direction perpendicular to the arrangement direction D1 and the intersecting direction (for example, height direction D3) like the hollow protrusions 32 of the elastic body 31 in the above-mentioned embodiment. The constituent material of the elastic body 31D is the same as the constituent material of the elastic body 31 described above.

[0112] The battery module according to the present modification 4 includes a battery pack provided with the above-mentioned partition plate 30D, and other configurations are the same as those of the above-mentioned embodiment. Therefore, in the present modification 4, it is possible to provide a battery module that can enjoy the same effects as those of the above-mentioned embodiment.

[0113] In the above-described embodiment and modified examples 1 to 4, the storage space 28 of the housing 20 is divided by a plurality of partition plates into four rows of storage chambers arranged in the width direction, but the present invention is not limited to this. For example, the plurality of partition plates may divide the storage space of the housing into each of the storage chambers in one row of the storage chamber group, or into each of the storage chambers in two or more rows of the storage chamber group. Furthermore, the number of partition plates dividing the storage space may be the number necessary to divide the storage space according to the stored battery cells, and may be, for example, two or more.

[0114] In the above-described embodiment and modified examples 1 to 4, the partition plates that separate the four rows of storage chambers are joined so as to be continuous from one side to the other side in the width direction of the housing, but the present invention is not limited to this. For example, each of the partition plates may be formed as a horizontally elongated partition plate having a width that extends from one side to the other side in the width direction of the housing.

[0115] In the above-described embodiment and modified examples 1 to 4, the flow paths of the coolant that cools the battery cells (inlet pipe 41, inlet branch pipe 42, outlet junction pipe 43, outlet pipe 44, inlet pipe 38a, and outlet pipe 38b) are piped so as to be exposed inside the housing, but the present invention is not limited to this. For example, a flow space for the coolant may be provided inside each side of the housing to which the side ends of the partition plates are joined, and the coolant may be made to flow from an inlet pipe provided in one side of the housing through the flow space in that one side into each of the cooling flow paths of the multiple partition plates, the coolant that has flowed through each of the cooling flow paths may be made to merge into a flow space formed in the other side of the housing, and the merged coolant may be made to flow out of the housing from an outlet pipe provided in that other side.

[0116] In addition, in the above-mentioned embodiment and modified examples 1 to 4, the number of each of the hollow protrusions and cooling channels provided in one partition plate is nine, but the present invention is not limited to this. For example, the number of each of the hollow protrusions and cooling channels provided in one partition plate may be one, or two or more.

[0117] In addition, in the above-described embodiment and modified examples 1 to 4, the hollow protrusions and cooling channels extending in the width direction of the partition plate are exemplified, but the present invention is not limited to this. For example, the hollow protrusions and cooling channels provided in the partition plate may extend in a direction across the battery cells from the upstream side to the downstream side of the coolant flow path in the partition plate, and the extension direction of the hollow protrusions and cooling channels may be inclined with respect to the width direction.

[0118] In the above-described embodiment and modifications 1 to 4, the cooling flow passage having a rectangular cross section is formed in the elastic body of the partition plate, but the present invention is not limited to this. For example, the cooling flow passage of the partition plate may be formed so that its cross section is circular or elliptical.

[0119] In the above-mentioned embodiment and modified examples 1 to 4, the refrigerant inlet pipe is provided near the upper end of the housing in the height direction, and the refrigerant outlet pipe is provided near the lower end (bottom) of the housing in the height direction, but the present invention is not limited to this. For example, the refrigerant inlet pipe and outlet pipe may be provided at desired positions (upper end, lower end, center, etc.) on the side of the housing. Furthermore, the number of each of these inlet pipes and outlet pipes is not limited to one as described above, and may be multiple.

[0120] In the above-described embodiment and modifications 1 to 4, a pressure sensor is provided in the supply pipe leading to the inlet pipe of the battery pack, and this pressure sensor detects the pressure of the refrigerant in this supply pipe as the pressure between the battery cells in the battery pack and the refrigerant, but the present invention is not limited to this. For example, a pressure sensor may be provided between a battery cell located at one end in the arrangement direction of multiple battery cells contained in the battery pack and an end plate, and the pressure applied to the battery cell from the hollow protrusion of the partition plate may be detected as the pressure between the battery cells in the battery pack and the refrigerant.

[0121] In the above-described embodiment and modifications 1 to 4, the piping that forms a refrigerant circulation path is illustrated as the piping that is connected to the battery pack, but the present invention is not limited to this. The piping that is connected to the inlet pipe of the battery pack and the piping that is connected to the outlet pipe of the battery pack do not need to be in communication with each other, that is, they do not need to be piping that forms a refrigerant circulation path.

[0122] In the above-mentioned embodiment and modified examples 1 to 4, the flow rate of the coolant flowing through the battery pack is controlled by controlling the pump based on the pressure of the coolant detected by the pressure sensor, but the present invention is not limited to this. For example, the flow rate of the coolant flowing through the battery pack may be controlled based on the voltage of the battery cells in the battery pack based on the phenomenon that the higher the voltage of the battery cell (i.e., the higher the charge level), the greater the expansion of the battery cell, and the lower the voltage of the battery cell (i.e., the lower the charge level), the smaller the expansion of the battery cell. In detail, a voltmeter may be provided in the battery pack instead of the pressure sensor, and the voltmeter may measure the voltage of the battery cells in the battery pack. When the measured voltage is higher than or equal to an upper reference value, the control unit may control the pump to reduce the flow rate of the coolant, and when the measured voltage is lower than or equal to a lower reference value, the control unit may control the pump to increase the flow rate of the coolant.

[0123] In the above-described embodiment and modified examples 1 to 4, a heat insulating material is interposed between the hollow protrusions of the partition plate (hollow protrusions of the elastic body) and the battery cells, but the present invention is not limited to this. For example, the heat insulating material may be integrated with the base portion of the elastic body by a technique such as insert molding, or may be interposed between the hollow protrusions of the elastic body and the battery cells. Alternatively, the heat insulating material may not be provided between the battery cells. In this case, the hollow protrusions of the partition plate may be in direct contact with the abdominal surface portions of the battery cells that face each other in the above-described arrangement direction.

[0124] Furthermore, the present invention is not limited to the above-mentioned embodiment and modifications 1 to 4, and the present invention also includes configurations in which the above-mentioned components are appropriately combined. In addition, other embodiments, examples, operation techniques, etc. made by those skilled in the art based on the above-mentioned embodiment and modifications 1 to 4 are all included in the scope of the present invention. [Explanation of symbols]

[0125] 1 Battery module 10 Battery pack 11, 11a, 11b Battery cells 11-1~11-4 Battery cell group 12 Outer case 13a, 13b Ventral part 14a, 14b side part 15 Bottom 16 Lid 17, 18 Electrode terminal 20. Cabinet 21 Bottom 22a, 22b, 22c, 22d Side 23a, 23b, 23c, 23d, 23e, 23f, 23g, 23h End plates 24a, 24b, 24c, 24d Support plate 28 Containment Space 29 Containment Room Containment rooms 29-1~29-4 30, 30A, 30B, 30C, 30D, 30-1~30-3 Partition plate 31, 31A, 31B, 31C, 31D Elastic body 31a Base 32, 32B, 32C, 32D hollow protrusion 33, 33A Cooling Channel 34 Cooling plate 35a, 35b hollow end 36a Inlet 36b Outlet 37a, 37b communication port 38a, 38a-1~38a-4 Inlet pipe 38b, 38b-1~38b-4 Outlet pipe 39 Insulation 41 Inlet pipe 42 Inlet branch pipe 43 Outlet merge pipe 44 Outlet pipe 61 Pump 62 Pressure Sensor 63 Upstream valve 64 Downstream valve 68 Control Unit 69 Cooling device 70 Piping 71 Supply pipe 72 Outflow pipe 73 Circulation tube 80 Refrigerant D1 Array direction D2 width direction D3 Height direction

Claims

1. a housing having a storage space in which a plurality of battery cells are arranged in a stacked manner; a plurality of partition plates provided in the housing at intervals that sandwich each of the plurality of battery cells in an arrangement direction of the plurality of battery cells so as to separate the storage space into each of the plurality of battery cells; Equipped with Each of the plurality of partition plates is an elastic body having a hollow protrusion that protrudes to one side in the arrangement direction and is recessed when viewed from the other side in the arrangement direction; a cooling plate having a higher thermal conductivity than the elastic body and joined to the elastic body so as to cover a cooling flow path formed by a recess of the hollow protrusion on the other side of the arrangement direction; Equipped with the hollow protrusion applies a load to battery cells that face each other in the arrangement direction among the plurality of battery cells, the cooling plate performs heat exchange between a battery cell among the plurality of battery cells that is in contact with the battery cell in the arrangement direction and a refrigerant that flows through the cooling flow path. A battery module comprising:

2. the cooling plate is a metal plate or a resin plate that can deform in response to expansion and contraction of a battery cell that is in contact with the cooling plate in the arrangement direction among the plurality of battery cells. The battery module according to claim 1 .

3. a heat insulating material interposed between each of the plurality of battery cells and the elastic body; 3. The battery module according to claim 1 or 2.

4. The hollow protrusion is formed so as to extend in a cross direction intersecting the arrangement direction.

3. The battery module according to claim 1 or 2.

5. The hollow protrusions are provided on the elastic body so as to be aligned in a direction perpendicular to the arrangement direction and the intersecting direction. The battery module according to claim 4 .

6. a pump that delivers the coolant to the cooling passage through a pipe at a variable flow rate; a pressure sensor that detects a pressure between the refrigerant and a battery cell that faces the hollow protrusion in the arrangement direction among the plurality of battery cells; a control unit that causes the pump to adjust the flow rate of the coolant so that the pressure detected by the pressure sensor is within an allowable range for the battery cell to which the load is applied; and The battery module according to claim 1 or 2, further comprising:

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