Power storage device and method for manufacturing a power storage device

Abstract

A power storage device (100) comprises a power storage module (10), a thermally conductive material (40) having a thermally conductive layer (41) stacked on the power storage module (10) in a Z-direction, and a cooler (30) stacked on the thermally conductive layer (41) in the Z-direction. The cooler (30) comprises a contact surface (32) that comes into contact with the thermally conductive layer (41) and an outer surface (33) that opposes the contact surface (32). The cooler (30) has a through-hole (31) through which the contact surface (32) communicates with the outer surface (33).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This non-provisional application is based on Japanese Patent Application No. 2024-008873 filed with the Japan Patent Office on January 24, 2024, the entire contents of which are hereby incorporated by reference. BACKGROUND area

[0002] The present disclosure relates to a power storage device and a method of manufacturing a power storage device. Description of the state of the art

[0003] Japanese Patent No. 2023-046670 discloses a power storage device comprising a casing accommodating stacks of power storage devices, a cooler, and a thermally conductive material disposed between the casing and the cooler. The thermally conductive material is enclosed (under pressure) between the cooler and the stacks (the casing) to expand. SUMMARY

[0004] In the power storage device device described in Japanese Patent Application No. 2023-046670, air entrapment occurs in the thermally conductive material located between the cooler and the power storage modules during manufacturing, resulting in a reduction in the cooling efficiency of the power storage stacks (power storage module) by the cooler.

[0005] The present disclosure was made to solve the problem described above. The object of the present disclosure is to provide a power storage device and a method for manufacturing a power storage device that can suppress a decrease in the cooling efficiency of a power storage module when a thermally conductive material is provided between a cooler and the power storage module.

[0006] A power storage device according to a first aspect of the present disclosure includes: a power storage module having a plurality of power storage cells; a thermally conductive material having a thermally conductive layer stacked on the power storage module in a stacking direction; and a cooler stacked on the thermally conductive layer in the stacking direction. The cooler includes a first surface that comes into contact with the thermally conductive layer and a second surface opposite to the first surface. The cooler has a through-hole that causes the first surface to communicate with the second surface.

[0007] In the power storage device according to the first aspect of the present disclosure, the through-hole through which the first surface communicates with the second surface is formed in the cooler. This allows air trapped between the cooler and the power storage module to be discharged from the through-hole when the thermally conductive material (thermally conductive layer) is pressurized by the cooler and the power storage module. As a result, the pressurization cannot be hindered by the air. This can suppress deterioration of contact between the cooler and the thermally conductive material (thermally conductive layer) and contact between the power storage module and the thermally conductive material (thermally conductive layer). This can suppress a reduction in the cooling efficiency of the power storage module by the cooler.

[0008] In the power storage device according to the first aspect described above, the thermally conductive material preferably includes a filling portion formed adjacent to the thermally conductive layer and filling the through-hole. The filling portion contacts an inner surface of the through-hole. With this configuration, the contact area between the cooler and the thermally conductive material can be increased by a portion of the inner surface area in contact with the filling portion. This can further suppress a reduction in the cooling efficiency of the power storage module by the cooler.

[0009] In this case, the thermally conductive material preferably includes a protrusion formed adjacent to the filling portion and protruding from the through-hole to a side opposite the thermally conductive layer. The protrusion is in contact with the second surface. With this configuration, the contact area between the thermally conductive material and the cooler can be increased, and deformation of the cooler in the direction in which the through-hole passes can also be suppressed.

[0010] In the power storage device according to the first aspect described above, the through-hole is preferably formed at a location where the through-hole overlaps a central portion of the power storage module in the stacking direction in a direction intersecting the stacking direction. This easily traps air in the central portion of the power storage module in the direction intersecting the stacking direction. Thus, the above-described configuration can effectively exhaust air from the through-hole.

[0011] In the power storage device according to the first aspect described above, the through-hole is preferably formed at a position where the through-hole overlaps one end of the power storage module in a direction intersecting the stacking direction. This makes it easy for the thermally conductive material at the end of the power storage module in the direction intersecting the stacking direction to peel off due to external shocks or the like. Thus, the above-described configuration can suppress deterioration of the contact between the thermally conductive material and the power storage module at the end of the power storage module, effectively preventing the thermally conductive material from peeling off the power storage module.

[0012] In the power storage device according to the first aspect described above, the plurality of power storage cells are preferably arranged in an arrangement direction that intersects the stacking direction. The through-hole is formed at a position where the through-hole overlaps a gap between adjacent power storage cells in the arrangement direction of the plurality of power storage cells in the stacking direction. With this configuration, the air trapped between the power storage cells can be easily discharged from the through-hole. This can also prevent deterioration of the contact between the cooler and the heat-conducting material and the contact between the power storage module and the heat-conducting material.

[0013] In this case, a width of the through-hole in the arrangement direction is preferably smaller than a width of each of the plurality of power storage cells in the arrangement direction. With this configuration, the contact area between the cooler and the thermally conductive material can be made larger than when the width of the through-hole is not smaller than the width of the power storage cell. Also, an excessive increase in the amount of thermally conductive material (thermally conductive layer) between the power storage module and the cooler that is pushed out to the through-hole can be more effectively suppressed than when the width of the through-hole is not smaller than the width of the power storage cell.

[0014] In the power storage device in which the power storage module includes a plurality of power storage cells, the width of the through-hole in the arrangement direction is preferably larger than the distance between adjacent power storage cells of the plurality of power storage cells in the arrangement direction. With this configuration, the air trapped between the cooler and the power storage module can be discharged from the through-hole more efficiently than when the width of the through-hole is not larger than the above-described distance. Compared with the case where the width of the through-hole is not larger than the above-described distance, the pushing out of the heat-conducting material (heat-conducting layer) between the power storage module and the cooler to the through-hole is facilitated, as if it were pushed into the gap between the power storage cells.

[0015] In this case, the through-hole is preferably formed to extend over at least two or more power storage cells of the plurality of power storage cells in the array direction. In this configuration, the gap between the power storage cells may slightly overlap the through-hole in the stacking direction.

[0016] A method for manufacturing a power storage device according to a second aspect of the present disclosure includes: a preparation step of preparing a cooler having a first surface and a second surface opposite to the first surface and having at least one through-hole that causes the first surface to communicate with the second surface; an application step of applying a thermally conductive material to at least one of the first surfaces of the cooler and a power storage module including a plurality of power storage cells; a stacking step of stacking the cooler and the power storage module after the application step such that the thermally conductive material comes into contact with the power storage module and the first surface of the cooler, respectively;and a pressing step in which, after the stacking step, either the cooler or the power storage module is pressed toward the other cooler or the power storage module;

[0017] In the method for manufacturing a power storage device according to the second aspect of the present disclosure, as described above, one of the power storage module and the cooler having at least one through-hole that causes the first surface to communicate with the second surface is pressed against the other of the power storage module and the cooler. In this way, the pressing step can be performed while purging the air trapped between the cooler and the power storage module from the through-hole. As a result, a method for manufacturing a power storage device capable of suppressing a reduction in the cooling efficiency of a power storage module by a cooler can be provided.

[0018] In the method for manufacturing a power storage device according to the second aspect described above, the at least one through-hole preferably includes a plurality of through-holes. The pressing step is the step of pressing a portion of the cooler provided between through-holes of the plurality of through-holes toward the power storage module. This configuration can suppress the adhesion of the thermally conductive material in the through-hole to a device used in pressing, etc., when the thermally conductive material is forced out toward the through-hole in the pressing step.

[0019] The foregoing and other objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description of the present disclosure when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing a configuration of a power storage device according to an embodiment. Fig. 2 is a perspective view showing a configuration of a power memory cell according to the embodiment. Fig. 3 is a plan view of a cooler according to the embodiment, seen from the side Z1. Fig. 4 is a sectional view along the line IV-IV of Fig. 3. Fig. 5 is a sectional view along the line VV of Fig. 3. Fig. 6 is a flowchart showing a method of manufacturing a power storage device according to the embodiment. Fig. 7 is a sectional view showing a power storage module and a thermally conductive material after performing step S2 of Fig. 6 shows. Fig. 8 is a sectional view showing the power storage module, the thermally conductive material, and the cooler after performing step S3 of Fig. 6 shows. Fig. 9 is a view showing a pressing member and the pressing member formed in step S4 of Fig. 6 shows the cooler used, seen from side Z1. Fig. 10 is a first view showing a cross section of a power storage device according to a modification of the embodiment. Fig. 11 is a second view showing a cross section of a power storage device according to a modification of the embodiment. Fig. 12 is a third view showing a cross section of a power storage device according to a modification of the embodiment. Fig. 13 shows a modification of step S2 of Fig. 6. Fig. 14 shows a modification of step S4 of Fig. 6. Fig. 15 is a fourth view showing a cross section of a power storage device according to a modification of the embodiment. DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Embodiments of the present disclosure will be described in detail below with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and their description will not be repeated.

[0021] The vertical direction is referred to herein as the Z direction. Specifically, the upward and downward directions of the extension direction are referred to as the Z1 direction and the Z2 direction, respectively. The X direction and the Y direction are each a direction orthogonal to the Z direction (ie, a horizontal direction). The X direction is orthogonal to the Y direction. The X direction and the Z direction are examples of the "arrangement direction" and the "stacking direction" in the context of the present disclosure, respectively. <Konfiguration der Leistungsspeichervorrichtung>

[0022] Fig. Figure 1 is a perspective view showing a configuration of a power storage device 100 according to the present embodiment. The power storage device 100 is, for example, a device for storing electric energy for driving an electric vehicle (not shown). Fig. For example, the X direction shown in Figure 1 is the forward-backward direction of the electric vehicle. The Y direction is the right-left direction of the electric vehicle. The power storage device 100 may be housed in an electrical device (e.g., a stationary power storage device) other than the electric vehicle.

[0023] The power storage device 100 includes a power storage module 10, a housing 20, a cooler 30, and a thermally conductive material 40. A plurality of power storage modules 10 may be provided. For example, a plurality of power storage modules 10 may be arranged adjacent to one another in the X direction.

[0024] Fig. Figure 2 is a perspective view showing the structure of one of a plurality of power storage cells 11 included in the power storage module 10. The power storage cells 11 have the same structure and the same orientation. Each of the power storage cells 11 is shaped to extend in the Y direction. Specifically, the power storage cell 11 has the shape of a prism extending in the Y direction. The power storage cells 11 are arranged (stacked) in the X direction (see Fig. 3).

[0025] The power storage cell 11 has a length L1 in the Y direction. The power storage cell 11 has a length L2 in the X direction. The length L1 is greater than the length L2. In other words, the power storage cell 11 has the Y direction as its longitudinal direction. The power storage cell 11 also has a height H in the Z direction. The height H is less than the length L1. The height H is greater than the length L2. Each of the power storage cells 11 can be arranged to extend in the X direction.

[0026] As in Fig. 1, the power storage module 10 is housed in a housing 20. The housing 20 includes an upper housing 21 and a lower housing 22. The power storage module 10 is housed in the space defined by the connection of the upper housing 21 to the lower housing 22. The cooler 30 is also housed in the space described above. The configuration of the housing 20 is not limited to the Fig. 1. For example, the power storage module 10 may be arranged (housed) in a housing without a top case.

[0027] The cooler 30 cools the power storage module 10. The cooler 30 is arranged above (on the Z1 side) the power storage module 10. The cooler 30 is provided to cover the power storage module 10 from the Z1 side. Specifically, the cooler 30 is stacked on a thermally conductive layer 41 (described later) contained in the thermally conductive material 40 in the Z direction. The cooler 30 has a plate shape extending along the XY plane. A flow path (not shown) through which a coolant flows is formed in the cooler 30.

[0028] Fig. 3 is a plan view of the cooler 30 as seen from the side Z1. As in Fig. 3, each of the power storage cells 11 is covered from the Z1 side by the cooler 30. In the cooler 30, several (in Fig. 3 five through holes 31 are formed. The through holes 31 are formed in the central portion and at the four corners of the cooler 30. The through hole 31 has a circular (full-circle) shape when viewed from the Z1 side. The arrangement position and number of the through holes 31 in the cooler 30 are not limited to the examples described above. The through holes 31 will be described in detail later.

[0029] Fig. 4 is a sectional view along the line IV-IV of Fig. 1. The thermally conductive material 40 includes a thermally conductive layer 41 stacked on the power storage module 10 in the Z direction. The thermally conductive layer 41 is arranged on the end faces 11a of the power storage cells 11 on the Z1 side. The thermally conductive layer 41 is sandwiched between the power storage module 10 and the cooler 30 in the Z direction. In other words, the thermally conductive layer 41 is in contact with both the power storage module 10 and the cooler 30.

[0030] The cooler 30 has a contact surface 32 and an outer surface 33. The contact surface 32 is in contact with the thermally conductive layer 41. The outer surface 33 is a surface opposite the contact surface 32. The contact surface 32 and the outer surface 33 are examples of the "first surface" and the "second surface," respectively, within the scope of this disclosure.

[0031] Air may be trapped between the cooler and the power storage module. Therefore, during the manufacturing of a power storage device, the air may impede the pressurization of the heat-conducting layer by the cooler and the power storage module. In such a case, the contact between the cooler and the heat-conducting layer, and the contact between the power storage module and the heat-conducting layer, may deteriorate. This leads to a reduction in the cooling efficiency of the power storage module by the cooler.

[0032] In the present embodiment, the through-hole 31 is formed such that the contact surface 32 communicates with the outer surface 33. In other words, the through-hole 31 is provided so that the space on the contact surface 32 side communicates (connects) with the space on the outer surface 33 side. This allows the air trapped between the cooler 30 and the power storage module 10 to be discharged from the through-hole 31 during the manufacture of the power storage device 100.

[0033] The through-hole 31 is a hole (through hole) extending in the Z direction. The through-hole 31 extends orthogonally to the thermally conductive layer 41 and the cooler 30. The through-hole 31 is shaped to extend rectilinearly in the Z direction. The width W1 of the through-hole 31 in the X direction does not change depending on the position in the Z direction. In other words, the width W1 remains constant regardless of the position in the Z direction. The width W1 is an example of the "width of the through-hole in the arrangement direction" in the present disclosure.

[0034] The thermally conductive material 40 includes a filling portion 42. The filling portion 42 is a portion of the thermally conductive material 40 that fills through the through-hole 31. The filling portion 42 is formed adjacent to the thermally conductive layer 41. The filling portion 42 is a portion that is pushed out (released) from the area between the cooler 30 and the power storage module 10 through the through-hole 31 when the thermally conductive material 40 between the cooler 30 and the power storage module 10 is pressurized.

[0035] The filling portion 42 is in contact with an inner surface 31a of the through-hole 31. Specifically, the filling portion 42 fills the entire interior of the through-hole 31. In other words, there is no space within the through-hole 31 where the heat-conducting material 40 is not present.

[0036] The thermally conductive material 40 has a protrusion 43. The protrusion 43 is a portion that protrudes from the through-hole 31 to the side opposite the thermally conductive layer 41 (Z1 side). The protrusion 43 is formed adjacent to the filling portion 42. The protrusion 43 is a portion of the thermally conductive material 40 that overflows (leaks) from the through-hole 31 when the thermally conductive material 40 is forced into the through-hole 31 as described above.

[0037] The projection 43 is in contact with the outer surface 33 of the cooler 30. The projection 43 includes a contact surface 43a that comes into contact with the outer surface 33. The contact surface 43a is shaped, for example, to surround the through-hole 31. In other words, the contact surface 43a has an annular shape.

[0038] The width W1 of the through-hole 31 in the X direction is smaller than the width W2 of each of the power storage cells 11 in the X direction. The width W1 is also larger than the distance D between adjacent power storage cells 11 in the X direction. For example, the width W1 may be no less than twice the distance D. The width W1 may also be no more than four-fifths of the width W2. The width of the through-hole 31 means a hole size (diameter) of the through-hole 31. The width W2 is an example of the "width of each of the plurality of power storage cells in the arrangement direction" in the present disclosure.

[0039] The through-hole 31 is formed at a position where the through-hole 31 overlaps a gap G in the Z direction between adjacent power storage cells 11 in the X direction. Specifically, the gap G is located at a position where the gap G in the Z direction overlaps the central portion of the through-hole 31 in the X direction. The distance D described above is the width of the gap G in the X direction.

[0040] The through-hole 31 is formed to extend across two power storage cells 11 in the X direction. Specifically, the through-hole 31 is provided across two power storage cells 11 with a gap G therebetween, overlapping the through-hole 31 in the Z direction.

[0041] Again referring to Fig. 3 is the through-opening 31 arranged in the middle of the cooler 30 (through-opening 31 in Fig. 4) is formed at a position where the through-hole 31 overlaps a central portion 10a of the power storage module 10 in the Z direction. The central portion 10a is located at the center of the power storage module 10 in both the X direction and the Y direction.

[0042] The through-holes 31 arranged in the four corners of the cooler 30 are formed at locations where the through-holes 31 overlap the ends (10b, 10c) of the power storage module 10 in the X direction. The end 10b is an X1-side end of the power storage module 10. The end 10c is an X2-side end of the power storage module 10.

[0043] Of the four through-holes 31 arranged at four corners of the cooler 30, two through-holes 31 are formed on the X1 side at positions where these through-holes 31 overlap the Z-direction end 10b. One of these two through-holes 31 on the X1 side is also arranged at a position where this through-hole 31 overlaps an end 10d of the Y1 side power storage module 10 in the Z direction. The other of these two through-holes 31 on the X1 side is also arranged at a position where the other through-hole 31 overlaps an end 10e of the Y2 side power storage module 10 in the Z direction.

[0044] Of the four through-holes 31 described above, two through-holes 31 on the X2 side are arranged at positions where these through-holes 31 overlap the end 10c in the Z direction. One of these two through-holes 31 on the X2 side is also arranged at a position where this through-hole 31 overlaps the end 10d of the power storage module 10 in the Z direction. The other of these two through-holes 31 on the X2 side is also arranged at a position where the other through-hole 31 overlaps the end 10e of the power storage module 10 in the Z direction.

[0045] Fig. 5 is a sectional view along the line VV of Fig. 3. The configurations of the through hole 31 and the heat-conducting material 40 in Fig. 5 are the same as in Fig. 4, so that a redundant description is omitted below. <Verfahren zur Herstellung einer Leistungsspeichervorrichtung>

[0046] Hereinafter, a method of manufacturing the power storage device 100 will be described with reference to Fig. 6 to 9. The method for manufacturing the power storage device 100 is not limited to the Fig. 6 shown manufacturing process.

[0047] In step S1, the step of preparing the cooler 30 is performed. Specifically, a cooler 30 is provided, which includes a contact surface 32 and an outer surface 33 and has through-openings 31 through which the contact surface 32 communicates with the outer surface 33.

[0048] In step S2, thermally conductive material 40 is applied to the power storage module 10. In particular, thermally conductive material 40 is applied to the end surface 11a (see Fig. 7) each power storage cell 11. The thermally conductive material 40 may be applied to each power storage cell 11 before the power storage cells 11 are arranged in the X direction, or the thermally conductive material 40 may be applied to each power storage cell 11 after the power storage cells 11 have been arranged in the X direction. Although Fig. 7 shows an example in which the thermally conductive materials 40 applied to the respective power storage cells 11 are connected (integrated) to each other, the thermally conductive materials 40 of the respective power storage cells 11 may be spaced apart from each other at this time.

[0049] In step S3, the stacking of the power storage module 10 and the cooler 30 is performed. As in Fig. As shown in Figure 8, the cooler 30 is arranged (stacked) on the thermally conductive material 40, which is stacked on the power storage module 10. As a result, the thermally conductive material 40 comes into contact with the power storage module 10 and the contact surface 32 of the cooler 30, respectively.

[0050] In step S4, the cooler 30 is pressed against the power storage module 10. Consequently, the thermally conductive material 40 between the cooler 30 and the power storage module 10 is pressurized. As shown in Fig. 9, the cooler 30 is formed by a plurality of (in Fig. 9 four) pressing elements 110, which are arranged on the Z1 side of the cooler 30, are pressed to the Z2 side.

[0051] Each of the pressing elements 110 presses a portion 34 of the cooler 30 provided between the through-holes 31. Specifically, the pressing elements 110 press the respective portions 34 between the through-hole 31 corresponding to the central portion 10a and the four through-holes 31 corresponding to the ends (10b to 10e). The pressing elements 110 can press the cooler 30 (portions 34) simultaneously with the same pressing force.

[0052] Since the thermally conductive material 40 is pressurized in the pressing step of step S4, air is released from the through-hole 31, and the thermally conductive material 40 is also forced through the through-hole 31. In this way, the filling portion 42 and the protrusion 43 are formed. In other words, the thermally conductive material 40 is deformed to form the filling portion 42 and the protrusion 43.

[0053] As described above, the cooler 30 in the present embodiment has a through-hole 31 through which the contact surface 32 communicates with the outer surface 33. This causes air trapped between the cooler 30 and the power storage module 10 to be discharged from the through-hole 31 when the thermally conductive material 40 is pressurized by the cooler 30 and the power storage module 10. This can further improve the adhesion between the thermally conductive material 40 (thermally conductive layer 41) and the cooler 30 and the power storage module 10. This can improve the cooling efficiency of the power storage module 10 by the cooler 30.

[0054] In the present embodiment, the thermally conductive material 40 includes a filler portion 42 formed adjacent to the thermally conductive layer 41 and filling the through-hole 31. The filler portion 42 is in contact with the inner surface 31a of the through-hole 31. This allows the contact area between the thermally conductive material 40 and the cooler 30 to be increased by an amount equal to the inner surface 31a. Since the filler portion 42, which is part of the thermally conductive material 40, has entered through the through-hole 31, misalignment of the cooler 30 can be suppressed.

[0055] In the present embodiment, the thermally conductive material 40 includes a protrusion 43 formed adjacent to the filling portion 42 and protruding from the through-hole 31 to the side opposite the thermally conductive layer 41. The protrusion 43 contacts the outer surface 33. Consequently, the contact area between the thermally conductive material 40 and the cooler 30 can be increased by the amount of the contact area between the protrusion 43 and the outer surface 33. Since the protrusion 43 contacts the outer surface 33, misalignment of the cooler 30 can be suppressed by the contact area between the protrusion 43 and the outer surface 33.

[0056] The embodiment in which the thermally conductive material 40 has a filling portion 42 and a protrusion 43 is included in the above description, but the present disclosure is not limited thereto. The thermally conductive material may not include the filling portion 42 and the protrusion 43. In the embodiment shown in Fig. 10, a thermally conductive material 140 contains, for example, only the thermally conductive layer 41. In the example shown in Fig. 11, a thermally conductive material 240 comprises only one thermally conductive layer 141. The thermally conductive layer 141 has a cavity V formed at a location where the cavity V overlaps the through-opening 31 in the Z direction. In the example shown in Fig. 12, a thermally conductive material 340 comprises only the thermally conductive layer 41 and the filling portion 42.

[0057] The example in which thermally conductive material 40 is applied to the power storage module 10 is described in the method for manufacturing the power storage device 100 in the present embodiment, but the present disclosure is not limited thereto. As in step S12 of Fig. 13, thermally conductive material 40 may be applied to the cooler 30 (contact surface 32).

[0058] The example in which the cooler 30 is pressed against the power storage module 10 is described in the method for manufacturing the power storage device 100 in the above embodiment, but the present disclosure is not limited thereto. As in step S14 of Fig. As shown in Figure 14, the power storage module 10 can be pressed toward the cooler 30. The cooler 30 can be pressed toward the power storage module 10, and the power storage module 10 can also be pressed toward the cooler 30.

[0059] The embodiment in which the portion 34 between the through-holes 31 is pressed by the pressing member 110 is described above, but the present disclosure is not limited thereto. For example, the pressing member 110 may be arranged to block the through-hole 31.

[0060] The embodiment in which the through-hole 31 extends in the Z direction is included in the above description, but the present disclosure is not limited thereto. For example, a through-hole may extend such that it is inclined with respect to the Z direction. A through-hole may also be non-rectilinear. For example, the through-hole may have a bent, curved, or other section.

[0061] However, the embodiment in which the filling portion 42 is in contact with the inner surface 31a of the through-hole 31 is not limited thereto in the present disclosure. The filling portion that fills the through-hole 31 may be spaced apart from the inner surface 31a.

[0062] The embodiment in which the through-hole 31 is formed at a position where the through-hole 31 overlaps the central portion 10a and the ends (10b to 10e) of the power storage module 10 in the Z direction is included in the above description, but the present disclosure is not limited thereto. The through-hole 31 may be formed at a position where the through-hole 31 overlaps only one of the central portions 10a and a single end (10b to 10e) in the Z direction. Through-holes 31 may be formed at positions where the through-hole 31 overlaps some of the ends 10b to 10e in the Z direction. The position where the through-hole 31 is arranged with respect to the power storage module 10 is not limited to the above-described example.

[0063] The embodiment in which the through-hole 31 corresponding to the central portion 10a is formed at a location where the through-hole 31 overlaps the gap G between the power storage cells 11 in the Z direction is described in the above embodiment, but the present disclosure is not limited thereto. For example, as shown in Fig. 15, the through-hole 31 corresponding to the central portion 10a may be formed at a position where the through-hole 31 does not overlap the gap G in the Z direction, but overlaps only one power storage cell 11 in the Z direction.

[0064] However, the embodiment in which the width W1 of the through-hole 31 in the X direction is smaller than the width W2 of the power storage cell 11 in the X direction is not limited thereto in the present disclosure. The width W1 must not be smaller than the width W2.

[0065] However, the embodiment in which the width W1 is greater than the distance D between the power storage cells 11 is not limited thereto in the present disclosure. The width W1 must not be greater than the distance D.

[0066] The embodiment in which the through-hole 31 in the cooler 30 is arranged over two power storage cells 11 is described in the above description, but the present disclosure is not limited thereto. A through-hole arranged over three or more power storage cells 11 can be formed in the cooler.

[0067] The embodiment in which the cooler 30 is pressed by the pressing member 110 is included in the above description, but the present disclosure is not limited thereto. For example, a base on which either the power storage module 10 or the cooler 30 is placed may be moved toward the other power storage module 10 and the cooler 30 to pressurize the thermally conductive material 40.

[0068] The embodiment in which the cooler 30 is arranged above the power storage module 10 is described in the above description, but the present disclosure is not limited thereto. A cooler may also be arranged below or to the side of the power storage module 10.

[0069] The embodiment in which the X-direction, the Y-direction, and the Z-direction are orthogonal to each other is described in the above example, but the present disclosure is not limited thereto. At least two directions of the X-direction, the Y-direction, and the Z-direction may intersect each other without being orthogonal to each other.

[0070] The embodiment in which the through-hole 31 has the shape of a perfect circle as viewed along the Z direction is described, but the present disclosure is not limited thereto. The through-hole may have a rectangular shape or the shape of an elongated hole as viewed along the Z direction.

[0071] The configurations (methods) of the embodiment and the changes described above can be combined with each other.

[0072] Although the embodiments of the present disclosure have been described, the embodiments disclosed herein are in all respects illustrative and not restrictive. The scope of the present disclosure is defined by the terms of the claims and is intended to include all changes within the scope and meaning consistent with the terms of the claims. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2024-008873

[0001] JP 2023-046670 [0003, 0004]

Claims

[1] Power storage device (100) comprising: a power storage module (10) having a plurality of power storage cells (11); a thermally conductive material (40, 140, 240, 340) having a thermally conductive layer (41, 141) stacked on the power storage module in a stacking direction; and a cooler (30) stacked in the stacking direction on the heat-conducting layer, wherein the cooler a first surface (32) in contact with the heat-conducting layer, and has a second surface (33) opposite the first surface, and the cooler has a through-opening (31) which causes the first surface to communicate with the second surface. [2] Power storage device according to claim 1, wherein the thermally conductive material has a filling portion (42) formed adjacent to the thermally conductive layer and filling the through-hole, and the filling section is in contact with an inner surface (31a) of the through opening. [3] Power storage device according to claim 2, wherein the heat-conducting material has a projection (43) formed adjacent to the filling portion and projecting from the through-hole to a side opposite the heat-conducting layer, and the projection is in contact with the second surface. [4] The power storage device according to any one of claims 1 to 3, wherein the through-hole is formed at a position where the through-hole in the stacking direction overlaps a central portion (10a) of the power storage module in a direction intersecting the stacking direction. [5] The power storage device according to any one of claims 1 to 3, wherein the through-hole is formed at a position where the through-hole in the stacking direction overlaps one end (10b, 10c, 10d, 10e) of the power storage module in a direction intersecting the stacking direction. [6] Power storage device according to one of claims 1 to 3, wherein the plurality of power storage cells are arranged in a direction intersecting the stacking direction and the through-hole is formed at a position where the through-hole overlaps a gap (G) in the stacking direction between power storage cells that are adjacent to each other in the arrangement in the direction among the plurality of power storage cells. [7] The power storage device according to claim 6, wherein a width (W1) of the through hole in the arrangement direction is smaller than a width (W2) of each of the plurality of power storage cells in the arrangement direction. [8] The power storage device according to claim 6, wherein a width (W1) of the through-hole in the arrangement direction is greater than a distance (D) between power storage cells adjacent to each other in the arrangement direction among the plurality of power storage cells. [9] The power storage device according to claim 8, wherein the through-hole extends in the arrangement direction over at least two or more power storage cells among the plurality of power storage cells. [10] A method of manufacturing a power storage device (100), the method comprising: a preparation step of preparing a cooler (30) having a first surface (32) and a second surface (33) opposite the first surface, the cooler having at least one through-hole (31) establishing a connection between the first surface and the second surface; an application step of applying a thermally conductive material (40, 140, 240, 340) to at least one of the first surfaces of the cooler and a power storage module (10) having a plurality of power storage cells (11); a stacking step of stacking the cooler and the power storage module after the application step such that the thermally conductive material comes into contact with the power storage module and the first surface of the cooler; and a pressing step to press either the cooler or the power storage module towards the other element after the stacking step.

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