Battery module

Abstract

To provide a battery module equipped with heating means that is efficient in heating (heat retention).SOLUTION: A battery module includes n stacked battery cells (n is an integer of 2 or greater) and m resin separators (m=n-1) inserted between adjacent stacked battery cells, at least one of the m resin separators has a heater function capable of generating heat.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to the structure of a battery module in which a plurality of battery cells are stacked.

Background Art

[0002] Patent Document 1 discloses a battery module (battery pack) in which a battery stack formed by stacking a plurality of battery cells is housed in a case serving as a housing. In this battery module, it is described that a heater substrate is installed on the bottom surface of the case to warm the lower surface of the battery stack (the bottom wall of each battery cell) at low temperatures when the performance deteriorates.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional battery module described in Patent Document 1, a heater substrate is installed on the bottom surface of the case. Therefore, only one surface of the heater substrate is in contact with the battery stack, and heat generated for heating escapes from the other surface that is not in contact with the battery stack. Thus, the conventional battery module has a problem that the efficiency of heating (heat retention) of the battery cells is not good.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a battery module provided with heating means having good heating (heat retention) efficiency.

Means for Solving the Problems

[0006] To solve the above problems, one aspect of the disclosed technology is a battery module including n battery cells (n is an integer of 2 or more) to be stacked, and m resin separators (m = n - 1) respectively inserted between adjacent battery cells in the stack, wherein at least one of the m resin separators has a heat-generable heater function.

Advantages of the Invention

[0007] According to the battery module of the present disclosure, since the resin separator having a heater function is provided between battery cells, the generated heat is less likely to escape to the outside, and the heating (heat retention) efficiency can be improved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0009] The battery module of the present disclosure incorporates a heater function in the resin separator inserted between battery cells having a stacked structure. As a result, heat is generated between battery cells, so the amount of heat escaping to the outside can be suppressed, and the battery cells can be efficiently heated.

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. For the purpose of easy understanding, the up-down, left-right, front-back directions are defined in advance as shown in each drawing, and the embodiments are described according to this definition.

[0011] <Embodiment> FIG. 1 is a schematic diagram for explaining the structure of a battery module 100 according to an embodiment of the present disclosure. The battery module 100 illustrated in FIG. 1 includes a storage case 110 and a battery stack 120 in its configuration.

[0012] The storage case 110 is a substantially box-shaped member formed of an insulating material such as resin, with one surface (upper side) being open. This storage case 110 is a housing for inserting the battery stack 120 from the opening surface and storing the battery stack 120. Although various shape processes such as a handle for carrying and holes for taking out connection terminals are also applied to the storage case 110, since they are not the main points of the present disclosure technology, their illustrations and descriptions are omitted.

[0013] The battery stack 120 is a structure in which a plurality of battery cells are electrically connected. FIG. 2 shows an exploded perspective view for explaining the detailed structure of the battery stack 120. The battery stack 120 shown in FIG. 2 is a laminate in which a plurality of battery cells 121a to 121d and a plurality of resin separators 122a to 122e are alternately stacked in the front-rear direction (lamination direction). Note that the number of battery cells 121a to 121d laminated as the battery stack 120 is not limited to the number shown in FIG. 2.

[0014] The plurality of battery cells 121a to 121d are substantially flat-plate-shaped rectangular unit batteries made of a secondary battery such as a lithium-ion battery, for example.

[0015] The plurality of resin separators 122a to 122e are substantially flat-plate-shaped members made of an insulating material such as resin that can electrically insulate between two adjacent battery cells among the plurality of battery cells 121a to 121d when laminated. Further, the plurality of resin separators 122a to 122e also have a function of a spacer for adjusting so that a uniform constant load is applied to each of the plurality of battery cells 121a to 121d in a state where the battery stack 120 is stored in the storage case 110.

[0016] Among these multiple resin separators 122a to 122e, at least one has a heat-generable heater function. In this embodiment, resin separators 122b and 122d have a heat-generable heater function. FIG. 3 shows an exploded perspective view for explaining the structures of resin separators 122b and 122d having a heater function. The resin separators 122b and 122d having a heater function shown in FIG. 3 include a base resin plate 1221, a metal heater pattern 1222, and a cover resin plate 1223.

[0017] The metal heater pattern 1222 is a heating member formed by shaping the wiring of a metal material (for example, copper, aluminum, stainless steel) that generates heat when energized into a bellows-shaped pattern. The wire diameter (thickness) of the wiring is smaller than the thickness (front-rear direction) of the resin separators 122b and 122d.

[0018] The base resin plate 1221 is a substantially flat plate-shaped member having insulation such as resin. A depression 12211 for accommodating the metal heater pattern 1222 is formed in the central portion of the base resin plate 1221.

[0019] The cover resin plate 1223 is a substantially flat plate-shaped member having insulation such as resin, similar to the base resin plate 1221. The cover resin plate 1223 is formed into a shape that fits into the depression 12211 of the base resin plate 1221, and is fitted onto the base resin plate 1221 from above the metal heater pattern 1222 accommodated in the depression 12211. Note that this fitting may be performed by press-fitting or by adhesion.

[0020] In this way, by sandwiching the metal heater pattern 1222 between the base resin plate 1221 and the cover resin plate 1223, resin separators 122b and 122d with a flat surface incorporating a heater are completed. The metal heater pattern 1222 is not exposed on the resin surface so as not to come into contact with and cause an electrical short to the battery cells 121a to 121d in the state of the completed resin separators 122b and 122d, and is arranged at a position where both of the sandwiched battery cells can be uniformly heated.

[0021] <Function and Effect> In the battery module 100 according to the present embodiment having the above-described structure, the resin separator 122b having a heater function is disposed sandwiched between the battery cell 121a and the battery cell 121b. With this arrangement, the battery cell 121a is heated by heat radiation from one surface (front side) of the heated resin separator 122b, and the battery cell 121b is heated by heat radiation from the other surface (rear side) of the heated resin separator 122b. Further, in the battery module 100, the resin separator 122d having a heater function is disposed sandwiched between the battery cell 121c and the battery cell 121d. With this arrangement, the battery cell 121c is heated by heat radiation from one surface (front side) of the heated resin separator 122d, and the battery cell 121d is heated by heat radiation from the other surface (rear side) of the heated resin separator 122d.

[0022] That is, in the structure of the battery module 100 according to the present embodiment, since both planes of the resin separators 122b and 122d are in close contact with the battery cells 121a to 121d, respectively, the area through which the heat generated in the resin separators 122b and 122d escapes to the outside is extremely reduced. Therefore, since it is difficult for heat to escape to the outside, the battery cells 121a to 121d can be heated (kept warm) efficiently and quickly.

[0023] Further, in the structure of the battery module 100 according to the present embodiment, by restraining the plurality of battery cells 121a to 121d with a constant load by the storage case 110 and the plurality of resin separators 122a to 122e, the resin separators 122b and 122d having the built-in metal heater pattern 1222 and the plurality of battery cells 121a to 121d can be sufficiently brought into close contact with each other. Therefore, the heat conduction sheet that was necessary in the structure of the conventional battery module can be omitted.

Industrial Applicability

[0024] The present disclosure can be applied to a battery module in which a plurality of battery cells are stacked.

Description of Symbols

[0025] 100 Battery Module 110 Storage Case 120 Battery Stack 121a - 121d Battery Cells 122a - 122e Resin Separators 1221 Base Resin Plate 1222 Metal Heater Pattern 1223 Cover Resin Plate 12211 Depression

Claims

**Claim 1** n battery cells to be stacked (n is an integer of 2 or more), m resin separators (m = n - 1) respectively inserted between the adjacent battery cells when stacked, A battery module comprising: At least one of the m resin separators has a heat-generable heater function. Battery module. **Claim 2** The battery module according to claim 1, wherein the resin separator having the heater function and the resin separator not having the heater function are alternately inserted between the battery cells. **Claim 3** The battery module according to claim 1 or 2, wherein the resin separator having the heater function is formed by sandwiching a heater pattern made of metal between two resin plates.

Images