Manufacturing method for battery module

Abstract

A manufacturing method for a battery module including: a first step for attaching, to each of a plurality of cylindrical cells, a cylindrical cover member for covering the outer circumferential surface of the cell; a second step for positioning a first cell group in which a plurality of first cells among the plurality of cells to which the cover members are attached are arranged in a first direction orthogonal to the axial direction of the first cells, a second cell group in which a plurality of second cells among the plurality of cells to which the cover members are attached are arranged in the first direction, and a tabular temperature control plate such that the first cell group and the second cell group face each other in a second direction orthogonal to the axial direction and the first direction, and that the temperature control plate is positioned in a space between the first cell group and the second cell group; and a third step for pressing a first surface of the temperature control plate in the second direction by using the first cell group and pressing a second surface of the temperature control plate in the second direction by using the second cell group, thereby performing corrugation on the temperature control plate.

Description

Method for Manufacturing Battery Module

[0001] The present invention relates to a method for manufacturing a battery module.

[0002] For example, Patent Document 1 discloses a battery pack in which a plurality of cells are arranged on both sides of a corrugated separator. In the battery pack of Patent Document 1, heat from the cells is transferred to the separator including a heat-conductive skeleton member and dissipated.

[0003] Japanese Unexamined Patent Publication No. 2012-160260

[0004] As an example of a battery module, there is one having a configuration in which a plurality of cylindrical cells are arranged on both surfaces of a corrugated temperature control plate. In a battery module having such a configuration, positional displacement of cells relative to the corrugated temperature control plate may occur during manufacturing. When cell positional displacement occurs, the heat transfer performance between the cells and the temperature control plate may vary.

[0005] Accordingly, an object of the present invention is to provide a method for manufacturing a battery module that can suppress positional displacement of cells relative to a temperature control plate.

[0006] In order to solve the above problem, a method for manufacturing a battery module according to an embodiment of the present invention comprises: a first step of attaching, to each of a plurality of cylindrical cells, a cylindrical cover member that covers an outer peripheral surface of the cell; a second step of arranging the first cell group, the second cell group and the temperature control plate such that a first cell group, in which a plurality of first cells among the plurality of cells attached with the cover members are arranged in a first direction perpendicular to the axial direction of the first cells, and a second cell group, in which a plurality of second cells among the plurality of cells attached with the cover members are arranged in the first direction, are positioned opposite to each other in a second direction perpendicular to both the axial direction and the first direction, and a flat temperature control plate is located in a space between the first cell group and the second cell group; and a third step of corrugating the temperature control plate by pressing a first surface of the temperature control plate in the second direction by the first cell group and pressing a second surface of the temperature control plate in the second direction by the second cell group.

[0007] According to the present invention, it is possible to suppress misalignment of cells relative to the temperature control plate.

[0008] Figure 1 is a schematic plan view showing an example of the configuration of a battery module according to this embodiment. Figure 2 is a flowchart illustrating the manufacturing method of the battery module according to this embodiment. Figure 3 is a plan view illustrating the mounting process, the arrangement process, and the corrugation process. Figure 4 is a plan view showing the state after the corrugation process is completed. Figure 5 is a plan view illustrating the removal process. Figure 6 is a side view illustrating the removal process. Figure 7 is a plan view showing the state after the removal process is completed. Figure 8 is a plan view illustrating the bonding process.

[0009] Embodiments of the present invention will be described in detail below with reference to the attached drawings. The specific dimensions, materials, numerical values, etc., shown in these embodiments are merely examples to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0010] (Battery Module Configuration) Figure 1 is a schematic plan view showing an example of the configuration of the battery module 1 according to this embodiment. In Figure 1, the X direction indicates, for example, the height direction of the battery module 1, the Y direction indicates the direction perpendicular to the X direction, and the Z direction indicates the direction perpendicular to both the X and Y directions.

[0011] The battery module 1 may be mounted on a vehicle 2, such as an electric vehicle equipped with a motor-generator as a power source. The vehicle 2 is not limited to an electric vehicle; it may also be a hybrid electric vehicle equipped with both a motor-generator and an engine as power sources. Furthermore, the battery module 1 is not limited to being mounted on a vehicle 2; it may be mounted on various devices.

[0012] The battery module 1 includes a case 10, a first cell group 12, a second cell group 14, and a temperature control plate 16. The first cell group 12, the second cell group 14, and the temperature control plate 16 are housed inside the case 10. Each of the first cell group 12 and the second cell group 14 contains a plurality of cells 20. Hereafter, for the sake of convenience, the first cell group 12 and the second cell group 14 will be referred to collectively as simply "cell group" without distinction.

[0013] Cell 20 is a single cell of a rechargeable secondary battery, such as a lithium-ion battery. Cell 20 is formed in a cylindrical shape. Note that the cylindrical shape here is not limited to a cylinder with an annular cross-section, but may also include a cylindrical shape with a circular cross-section. Furthermore, the cylindrical shape here is not limited to a perfect circle on its outer circumference, but for example, the outer circumference may be elliptical. Although not shown in the figures, each of the multiple cells 20 is electrically connected via wires and busbars.

[0014] Each of the multiple cells 20 is positioned upright relative to the bottom surface of the case 10 such that the axis of the cell 20 is in the height direction of the battery module 1 (X direction in Figure 1).

[0015] The first cell group 12 includes multiple first cells from a plurality of cells 20. The first cell group 12 is configured such that the plurality of first cells are arranged in a first direction (Y direction in Figure 1) perpendicular to the axis direction of the first cells. In other words, the first cell group 12 is configured such that the axis direction of each of the plurality of cells 20 is the X direction, and the plurality of cells 20 are arranged in the Y direction.

[0016] In the example shown in Figure 1, the first cell group 12 consists of three cells 20 arranged in the Y direction. However, the number of cells 20 constituting the first cell group 12 may be multiple, and may be two or less, or four or more.

[0017] The second cell group 14 is a cell group configured separately from the first cell group 12. The second cell group 14 includes multiple second cells from among multiple cells 20. The second cells are arranged so that their axial direction is aligned with the axial direction of the first cell. The second cell group 14 is configured by arranging multiple second cells in the first direction (Y direction in Figure 1) as described above. In other words, the second cell group 14 is configured so that the axial direction of each of the multiple cells 20 is in the X direction, and these multiple cells 20 are aligned in the Y direction. Thus, the first direction is the direction in which the multiple cells 20 of the first cell group 12 are aligned, as well as the direction in which the multiple cells 20 of the second cell group 14 are aligned.

[0018] In the example in Figure 1, the second cell group 14 is shown as four cells 20 arranged in the Y direction. However, the number of cells 20 constituting the second cell group 14 may be multiple, and may be 3 or less, or 5 or more. The number of cells 20 constituting the second cell group 14 may be the same as or different from the number of cells 20 constituting the first cell group 12.

[0019] The temperature control plate 16 is positioned between the first cell group 12 and the second cell group 14. The temperature control plate 16 is formed in a corrugated shape. The temperature control plate 16 is positioned such that the length direction corresponding to the direction of wave propagation on the temperature control plate 16 is the same as the direction in which the cells 20 of the cell group are aligned (i.e., the first direction).

[0020] A first cell group 12 is connected to the first surface 22 of the temperature control plate 16 via a heat transfer material 30. Each cell 20 of the first cell group 12 is housed in the trough of the wave formed on the first surface 22 of the temperature control plate 16. A second cell group 14 is connected to the second surface 24 of the temperature control plate 16, opposite to the first surface 22, via a heat transfer material 30. Each cell 20 of the second cell group 14 is housed in the trough of the wave formed on the second surface 24 of the temperature control plate 16.

[0021] The heat transfer material 30 is made of a material that has thermal conductivity. In addition to having heat transfer properties, the heat transfer material 30 also has adhesive properties. During the manufacturing process of the battery module 1, the heat transfer material 30 is fluid, and when the battery module 1 is completed, it becomes hardened. The heat transfer material 30, a fluid gel-like substance, hardens to bond the temperature control plate 16 to each cell 20. Once the temperature control plate 16 and each cell 20 are bonded by the heat transfer material 30, heat exchange becomes possible between the temperature control plate 16 and each cell 20 via the heat transfer material 30.

[0022] Although not shown in the diagram, a flow path for the heat transfer medium is formed inside the temperature control plate 16. The temperature control plate 16 exchanges heat between the heat transfer medium flowing through the internal flow path and each of the cells 20 in the first cell group 12 and the second cell group 14. Through this heat exchange, the temperature of each of the cells 20 in the first cell group 12 and the second cell group 14 is adjusted.

[0023] The battery module 1 includes at least one unit 40 in which a first cell group 12 is connected to a first surface 22 of a temperature control plate 16, and a second cell group 14 is connected to a second surface 24 of the same temperature control plate 16.

[0024] The battery module 1 may include multiple units 40. When it includes multiple units 40, the multiple units 40 are stacked in a second direction (Z direction in Figure 1) that is perpendicular to the axial direction and the first direction of the cell 20. In this case, an insulating sheet may be provided between adjacent units 40.

[0025] The battery module 1 has a predetermined hardened filler 42 filling the gaps between the units 40 in the case 10. This fixes the position of each component with the filler. Note that the battery module 1 does not necessarily need to be filled with the filler 42.

[0026] (Method for Manufacturing a Battery Module) Figure 2 is a flowchart illustrating the method for manufacturing the battery module 1 according to this embodiment. Hereafter, for the sake of convenience in explanation, the method for manufacturing the battery module 1 according to this embodiment may be simply referred to as "this manufacturing method."

[0027] As shown in Figure 2, this manufacturing method includes an installation step S10, a placement step S12, a corrugation process S14, a removal step S16, and a bonding step S18. Each step of this manufacturing method may be performed by a manufacturing machine, by a person, or by a combination of a manufacturing machine and a person.

[0028] (Mounting process S10) Figure 3 is a plan view illustrating the mounting process S10, the placement process S12, and the corrugation process S14. Figure 4 is a plan view showing the state after the corrugation process S14 has been completed.

[0029] As shown in Figure 3, this manufacturing method utilizes a cover member 50 that covers the outer circumference of the cell 20. The cover member 50 is made of a relatively high-strength metal material, such as carbon steel. The cover member 50 is formed in a cylindrical shape capable of housing the cell 20 inside. The outer and inner surfaces of the cover member 50 may be elliptical to match the shape of the cell's outer circumference. The inner diameter of the cover member 50 is substantially equal to the outer diameter of the cell 20. The inner diameter of the cover member 50 may include a tolerance sufficient to allow the cover member 50 to be attached to and detached from the cell 20. Both axial ends of the cover member 50 are open.

[0030] In installation step S10, a cover member 50 is attached to each of the multiple cells 20. More specifically, in installation step S10, the cell 20 is inserted into the interior of the cover member 50 through one end of the cover member 50. In installation step S10, the cover member 50 is attached to both the cells 20 that will constitute the first cell group 12 and the cells 20 that will constitute the second cell group 14.

[0031] (Placement Step S12) In placement step S12, the flat temperature control plate 16, the multiple cells 20 with the cover member 50 attached, the first pressing jig 60, and the second pressing jig 62 are placed on the bottom surface of the case 10, but they may also be placed on a predetermined workbench. Hereafter, for the sake of explanation, the cells 20 with the cover member 50 attached may be referred to as covered cells.

[0032] In the arrangement step S12, a first cell group 12 is formed by arranging multiple first cells from among multiple covered cells in a first direction (Y direction in Figure 3) perpendicular to the axial direction, with the axial direction of the first cell being the X direction. Also in the arrangement step S12, a second cell group 14 is formed by arranging multiple second cells from among multiple covered cells in a first direction (Y direction in Figure 3) perpendicular to the axial direction, with the axial direction of the second cell being the X direction. The first cell group 12 and the second cell group 14 are arranged opposite each other in the axial direction of the covered cells and in the second direction (Z direction in Figure 3) perpendicular to the first direction. There is space between the first cell group 12 and the second cell group 14.

[0033] The spacing between adjacent covered cells in the first cell group 12 is substantially the same as the spacing between adjacent covered cells in the second cell group 14. Multiple covered cells in the first cell group 12 are positioned offset in the first direction (Y direction in Figure 3) by half the spacing between adjacent covered cells in the first cell group 12 relative to multiple covered cells in the second cell group 14.

[0034] In the placement process S12, the temperature control plate 16 is a flat plate that has not undergone corrugation processing. In the placement process S12, the flat temperature control plate 16 is placed in the space between the first cell group 12 and the second cell group 14. The temperature control plate 16 is placed so that its length direction is in the direction in which the first cell group 12 and the second cell group 14 are aligned (Y direction in Figure 3). The temperature control plate 16 is placed upright on the bottom surface of the case 10 so that its width direction, which is perpendicular to its length direction and thickness direction, is the X direction in Figure 3.

[0035] Although not shown in the diagram, at least one end of the temperature control plate 16 in the longitudinal direction is gripped by a predetermined gripping member. This maintains the position of the temperature control plate 16. The gripping member is configured to grip the temperature control plate 16 in a manner that does not interfere with the corrugation process of the temperature control plate 16.

[0036] In this way, during the arrangement step S12, the first cell group 12, the second cell group 14, and the temperature control plate 16 are arranged such that the flat temperature control plate 16 is located in the space between the first cell group 12 and the second cell group 14, which are located opposite each other.

[0037] In the placement step S12, the temperature control plate 16 may be placed after the first cell group 12 and the second cell group 14 are placed, or the first cell group 12 and the second cell group 14 may be placed after the temperature control plate 16 is placed. In the placement step S12, either the first cell group 12 or the second cell group 14 may be placed first, or both the first cell group 12 and the second cell group 14 may be placed substantially simultaneously. In the placement step S12, the first cell group 12, the second cell group 14 and the temperature control plate 16 may be placed substantially simultaneously.

[0038] The first pressing jig 60 and the second pressing jig 62 are blocks having recesses capable of accommodating a covered cell. The recesses of the first pressing jig 60 and the second pressing jig 62 may be formed, for example, in a semicircular shape. The depth of the recesses of the first pressing jig 60 and the second pressing jig 62 may be set to a value substantially the same as the outer radius of the cover member 50, for example.

[0039] The first pressing jig 60 is positioned on the side opposite to the temperature control plate 16 relative to the first cell group 12 with the cover member 50 attached. The first pressing jig 60 is positioned so that the covered cells of the first cell group 12 are accommodated in its recess. The first pressing jig 60 is positioned, for example, in a one-to-one correspondence for each cell 20 of the first cell group 12. The first pressing jig 60 may be integrated across multiple covered cells of the first cell group 12.

[0040] The second pressing jig 62 is positioned on the side opposite to the temperature control plate 16 relative to the second cell group 14 with the cover member 50 attached. The second pressing jig 62 is positioned so that the covered cells of the second cell group 14 are accommodated in its recess. The second pressing jig 62 is positioned, for example, in a one-to-one correspondence for each cell 20 of the second cell group 14. The second pressing jig 62 may be integrated across multiple covered cells of the second cell group 14.

[0041] Furthermore, in the arranging step S12, the first pressing jig 60 may be arranged after the first cell group 12 is arranged, and the second pressing jig 62 may be arranged after the second cell group 14 is arranged. In the arranging step S12, the first cell group 12 may be arranged after the first pressing jig 60 is arranged, and the second cell group 14 may be arranged after the second pressing jig 62 is arranged. In the arranging step S12, the first cell group 12 and the first pressing jig 60 may be arranged substantially concurrently in parallel. In the arranging step S12, the second cell group 14 and the second pressing jig 62 may be arranged substantially concurrently in parallel.

[0042] (Corrugating step S14) In the corrugating step S14, as shown by the open arrow A10 in FIG. 3, the first surface 22 of the flat temperature adjustment plate 16 is pressed in the second direction (Z direction in FIG. 3) by the first cell group 12 with the cover member 50 attached thereto. At the same time, in the corrugating step S14, as shown by the open arrow A12 in FIG. 3, the second surface 24 of the flat temperature adjustment plate 16 is pressed in the second direction (Z direction in FIG. 3) by the second cell group 14 with the cover member 50 attached thereto. Accordingly, corrugation is performed on the flat temperature adjustment plate 16.

[0043] For example, the first pressing jig 60 and the second pressing jig 62 may be connected to a pressurizing device. Then, the pressurizing device may move the first pressing jig 60 and the second pressing jig 62 in directions approaching each other.

[0044] Accordingly, the side surface of each covered cell in the first cell group 12 is pressed against the first surface 22 of the temperature adjustment plate 16, and the side surface of each covered cell in the second cell group 14 is pressed against the second surface 24 of the temperature adjustment plate 16. When the temperature adjustment plate 16 is pressed, each covered cell of the first cell group 12 deforms the temperature adjustment plate 16 so as to dent toward the second cell group 14 side, and each covered cell of the second cell group 14 deforms the temperature adjustment plate 16 so as to dent toward the first cell group 12 side.

[0045] By doing so, as shown in FIG. 4, the temperature control plate 16 is corrugated, and the temperature control plate 16 is plastically deformed into a corrugated shape. More specifically, in the first surface 22 of the temperature control plate 16, valleys are formed in portions of the first cell group 12 against which the respective covered cells are pressed. In the second surface 24 of the temperature control plate 16, valleys are formed in portions of the second cell group 14 against which the respective covered cells are pressed.

[0046] As described above, since at least one end in the extending direction of the temperature control plate 16 is gripped by a predetermined gripping member, the position of the temperature control plate 16 is maintained in a state where the corrugation processing is completed.

[0047] As shown in FIG. 4, in a state where the corrugation processing of the temperature control plate 16 is completed, the position of each of the plurality of covered cells is located in a valley of the corrugated temperature control plate 16. That is, in a state where the corrugation step S14 is completed, each of the plurality of cells 20 is arranged at an appropriate position with respect to the corrugated temperature control plate 16.

[0048] As described above, in the present manufacturing method, positional displacement of the cells 20 relative to the temperature control plate 16 can be suppressed by performing corrugation processing on the temperature control plate 16 with the cells 20 to which the cover members 50 are attached. As a result, in the present manufacturing method, it is possible to suppress variation in heat transfer performance between the cells 20 and the temperature control plate 16 in the manufactured battery module 1.

[0049] Further, in the present manufacturing method, both the corrugation processing of the temperature control plate 16 and the positioning of the cells 20 with respect to the temperature control plate 16 can be performed in the same step. Therefore, in the present manufacturing method, the manufacturing process of the battery module 1 can be simplified.

[0050] Further, in the present manufacturing method, since corrugation processing of the temperature control plate 16 is performed in a state where the cover member 50 is attached to the cell 20, the cover member 50 can prevent the cell 20 from being damaged during the corrugation processing of the temperature control plate 16.

[0051] Furthermore, the cover member 50 is not limited to a cylindrical shape; at least the side facing the temperature control plate 16 should be arc-shaped, similar to the side of the cell 20.

[0052] (Removal process S16) Figure 5 is a plan view illustrating the removal process S16. Figure 6 is a side view illustrating the removal process S16. Figure 7 is a plan view showing the state after the removal process S16 has been completed.

[0053] As shown in Figure 5, a retaining jig 70 is used in the removal process S16. The retaining jig 70 is formed in a rod shape. The outer diameter of the retaining jig 70 is smaller than the inner diameter of the cover member 50. The length of the retaining jig 70 is longer than the length of the cover member 50.

[0054] In the removal process S16, the holding jig 70 presses down on the first axial end face of the cell 20 in the axial direction, thereby maintaining the position of the cell 20. In other words, the holding jig 70 presses down on the first end face of the cell 20 in a direction toward the second end face opposite to the first end face.

[0055] More specifically, the second end face of cell 20 is in contact with a predetermined plane. For example, the second end face of cell 20 is in contact with the bottom surface of case 10, but it may also be in contact with a predetermined workbench. The first end face of cell 20 is oriented upward. The first axial end of the holding jig 70 is in contact with the first end face of cell 20. The holding jig 70 is positioned to extend along the axial direction of cell 20. The same number of holding jigs 70 as there are cells 20 are prepared and one is placed for each cell 20.

[0056] A force is applied to the holding jig 70 that moves it toward the cell 20. As a result, the second end face of the cell 20 is supported by the bottom surface of the case 10, and the first end face of the cell 20 is pressed by the holding jig 70 toward the second end face of the cell 20. In other words, the position of the cell 20 is maintained by the predetermined plane and the holding jig 70.

[0057] In the removal process S16, with the position of each cell 20 held by the holding jig 70, the first pressing jig 60 and the second pressing jig 62 are removed from the side of the covered cell.

[0058] In the removal process S16, after the first pressing jig 60 and the second pressing jig 62 are removed, the cover member 50 is removed from each of the cells 20 while the positions of the multiple cells 20 are maintained, as shown in Figure 6.

[0059] More specifically, after the first pressing jig 60 and the second pressing jig 62 are removed, the position of the cell 20 is continued to be held by the holding jig 70. While the position of the cell 20 is being held by the holding jig 70, the cover member 50 is moved in the direction toward the holding jig 70 in the axial direction of the cell 20, as shown by the white arrow in Figure 6. In this way, the cover member 50 is pulled out from each of the multiple cells 20.

[0060] The length of the cover member 50 may be longer than the length of the cell 20. In this embodiment, the upper end of the cover member 50 will protrude above the upper end of the cell 20. In the removal step S16, the portion of the cover member 50 that protrudes above the upper end of the cell 20 may be gripped by a predetermined gripping member, and the cover member 50 may be pulled up relative to the cell 20 by the gripping member.

[0061] Thus, in this manufacturing method, after the temperature control plate 16 has been processed to create a corrugated surface, the positions of the multiple cells 20 are maintained, and the first pressing jig 60, the second pressing jig 62, and the cover member 50, which are ultimately unnecessary for the battery module 1, are removed.

[0062] As a result, in this manufacturing method, even if the first pressing jig 60, the second pressing jig 62, and the cover member 50 are removed, misalignment of the cell 20 relative to the temperature control plate 16 can be suppressed.

[0063] Furthermore, in this manufacturing method, the position of the cell 20 is maintained by the holding jig 70 when the first pressing jig 60, the second pressing jig 62, and the cover member 50 are removed, thus more reliably suppressing displacement of the cell 20.

[0064] After the removal of the cover member 50 is complete, the position of the cell 20 is continued to be held by the holding jig 70, as shown in Figure 7.

[0065] Furthermore, after the removal of the cover member 50 is complete, as shown in Figure 7, a gap substantially equal to the thickness of the cover member 50 is created between each cell 20 of the first cell group 12 and the first surface 22 of the temperature control plate 16. Similarly, a gap substantially equal to the thickness of the cover member 50 is created between each cell 20 of the second cell group 14 and the second surface 24 of the temperature control plate 16. From these observations, it can be seen that the cover member 50 not only protects the cells 20 when the temperature control plate 16 is subjected to corrugation processing, but also functions as a spacer that creates a predetermined gap between the cells 20 and the temperature control plate 16.

[0066] (Bonding process S18) Figure 8 is a plan view illustrating bonding process S18. As shown in Figure 8, a first spill prevention jig 80 and a second spill prevention jig 82 are used in bonding process S18.

[0067] The first spill prevention jig 80 and the second spill prevention jig 82 have recesses capable of accommodating the cells 20. The first spill prevention jig 80 is formed such that, with the cells 20 of the first cell group 12 accommodating it in its recess, its tip contacts the first surface 22 of the temperature control plate 16. The second spill prevention jig 82 is formed such that, with the cells 20 of the second cell group 14 accommodating it in its recess, its tip contacts the second surface 24 of the temperature control plate 16.

[0068] The first spill prevention fixture 80 is arranged for each cell 20 in the first cell group 12, for example, in a one-to-one correspondence with each cell 20. The first spill prevention fixture 80 may be integrated across multiple cells 20 in the first cell group 12. The second spill prevention fixture 82 is arranged for each cell 20 in the second cell group 14, for example, in a one-to-one correspondence with each cell 20. The second spill prevention fixture 82 may be integrated across multiple cells 20 in the second cell group 14.

[0069] In bonding step S18, with the position of the cells 20 held by the holding jig 70, the first spill prevention jig 80 is attached to the sides of multiple cells 20 of the first cell group 12, and the second spill prevention jig 82 is attached to the sides of multiple cells 20 of the second cell group 14.

[0070] When the first spill prevention jig 80 is attached to a cell 20 of the first cell group 12, a first gap is defined in the first cell group 12 by the side surface of the cell 20, the first surface 22 of the temperature control plate 16, and the first spill prevention jig 80. Similarly, when the second spill prevention jig 82 is attached to a cell 20 of the second cell group 14, a second gap is defined in the second cell group 14 by the side surface of the cell 20, the second surface 24 of the temperature control plate 16, and the second spill prevention jig 82.

[0071] In bonding step S18, a fluid, gel-like heat transfer material 30 is injected into the defined first and second gaps. After the heat transfer material 30 is injected, drying is performed until the heat transfer material 30 hardens. Once the heat transfer material 30 hardens, the cells 20 of the first cell group 12 are bonded to the first surface 22 of the temperature control plate 16 via the heat transfer material 30, and the cells 20 of the second cell group 14 are bonded to the second surface 24 of the temperature control plate 16 via the heat transfer material 30.

[0072] In bonding step S18, after the drying of the heat transfer material 30 is complete, the first spill prevention jig 80 and the second spill prevention jig 82 are removed. Subsequently, the first end of the holding jig 70 that was in contact with the cell 20 is separated from the cell 20, and the holding jig 70 releases its ability to hold the position of the cell 20.

[0073] Thus, in this manufacturing method, after the cover member 50 is removed from the cell 20, a heat-conductive heat transfer material 30 is introduced between the cell 20 and the temperature control plate 16. Therefore, in this manufacturing method, the cell 20 can be bonded to the temperature control plate 16 with the position of the cell 20 relative to the temperature control plate 16 determined. In other words, in this manufacturing method, heat exchange between the temperature control plate 16 and the cell 20 is possible via the heat transfer material 30 while suppressing misalignment of the cell 20 relative to the temperature control plate 16. As a result, in this manufacturing method, variations in the heat transfer performance between the cell 20 and the temperature control plate 16 can be suppressed in the battery module 1 after manufacturing.

[0074] Furthermore, in this manufacturing method, the thickness of the cover member 50 may be set to substantially the same value as the target value of the thickness of the cured heat transfer material 30 provided between the cell 20 and the temperature control plate 16. The thickness of the cover member 50 may also be a value that deviates from the target value of the cured heat transfer material 30 by an acceptable margin of error.

[0075] For example, the thickness of the heat transfer material 30 after curing may be set to a specific value of 0.3 mm to 1 mm, taking into consideration both the adhesive performance between the cell 20 and the temperature control plate 16 and the heat transfer performance between the cell 20 and the temperature control plate 16. In that case, the thickness of the cover member 50 may be set to a specific value of 0.3 mm to 1 mm, similar to the thickness of the heat transfer material 30 after curing.

[0076] As described above, when the cover member 50 is removed from the cell 20 after the temperature control plate 16 has been corrugated, a gap substantially equal to the thickness of the cover member 50 is created between the cell 20 and the temperature control plate 16. In this manufacturing method, by sending a fluid heat transfer material 30 into the gap after the cover member 50 has been removed and curing it, the thickness of the cured heat transfer material 30 can be easily set to the target value. As a result, this manufacturing method makes it possible to achieve appropriate adhesive performance and heat transfer performance of the heat transfer material 30.

[0077] In the case of a battery module 1 including multiple units 40, each step in Figure 2 may be performed in parallel for the multiple units 40, or each step in Figure 2 may be repeated for each unit 40.

[0078] Although not shown in the flowchart of Figure 2, after the bonding process S18, a predetermined fluid filler 42 is introduced into the case 10. Subsequently, the filler 42 is dried and hardened.

[0079] Embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these embodiments. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention.

[0080] 1 Battery module 12 First cell group 14 Second cell group 16 Temperature control plate 20 Cell 22 First surface 24 Second surface 30 Heat transfer material 50 Cover member 70 Holding jig

Claims

1. A method for manufacturing a battery module, comprising: a first step of attaching a cylindrical cover member to each of a plurality of cylindrical cells to cover the outer surface of the cell; a second step of arranging the first cell group, the second cell group and the temperature control plate such that a plurality of first cells from the plurality of cells to which the cover member is attached are arranged in a first direction perpendicular to the axial direction of the first cell, and a plurality of second cells from the plurality of cells to which the cover member is attached are arranged in a first direction, facing each other in a second direction perpendicular to the axial direction and the first direction, and a flat temperature control plate is positioned in the space between the first cell group and the second cell group; and a third step of processing the temperature control plate to create a corrugated shape by pressing the first surface of the temperature control plate in the second direction with the first cell group and pressing the second surface of the temperature control plate in the second direction with the second cell group.

2. A method for manufacturing a battery module according to claim 1, further comprising a fourth step of removing the cover member from each of the plurality of cells while maintaining the positions of the plurality of cells after the third step.

3. The method for manufacturing a battery module according to claim 2, wherein the fourth step is to press the first end face of the cell in the axial direction against the first end face of the cell in the axial direction using a predetermined jig having an outer diameter smaller than the inner diameter of the cover member, thereby holding the position of the cell, and then pull out the cover member from each of the plurality of cells.

4. A method for manufacturing a battery module according to claim 2, further comprising a fifth step of introducing a fluid heat transfer material into the gap between the outer circumferential surface of each of the plurality of cells and the temperature control plate after corrugation processing, after the fourth step.

5. The method for manufacturing a battery module according to claim 4, wherein the thickness of the cover member is set to substantially the same value as the target value of the thickness of the cured heat transfer material provided between the cell and the temperature control plate.

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