Spacer

Abstract

To provide a spacer which can suppress degradation of power storage cells caused by heat generation.SOLUTION: A spacer 20 comprises: a plate 30 provided with a plurality of ribs; and a heat conduction member 40. When in an arrangement condition arranged between power storage cells adjacent to each other, the plate 30 includes: a first region R1 including a first facing region R10 which faces a power collection part of a power storage element and a second facing region R20 which faces a central part of the power storage element; and a second region R2 including regions R3, R4 which are located between the first facing region R10 and the second facing region R20. The plurality of ribs include: a first rib 32 which defines the first region R1 and the second region R2; and second ribs 33, 34, and 35 which are provided in the first facing region R10 and the second facing region R20. In the arrangement condition, the first region R1 is provided so as to extend upward from a lower end of the power storage cell, and the heat conduction member 40 is provided in the first region R1, when viewed from an alignment direction in which the adjacent power storage cells are aligned.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a spacer, and more particularly to a spacer disposed between adjacent energy storage cells. [Background technology]

[0002] Conventionally, as a spacer arranged between adjacent batteries (energy storage cells), Japanese Patent Application Laid-Open No. 2022-62288 (Patent Document 1) discloses a plate-shaped spacer whose upper region is composed of a heat conduction suppressing portion and whose lower region is composed of a heat conduction promoting portion. In the region above the battery that contacts the heat conduction suppressing portion, heat transfer to the adjacent battery is suppressed, and in the region below the battery that contacts the heat conduction promoting portion, heat transfer to the adjacent battery is promoted. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-62288 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the current collector and current collecting member of the electrode body, which generate a lot of heat, are arranged on the upper side of the battery, and the configuration of Patent Document 1 does not allow the current collector and current collecting member to be sufficiently cooled, and therefore, battery degradation cannot be sufficiently suppressed.

[0005] The present disclosure has been made in view of the above-described problems, and an object of the present disclosure is to provide a spacer that can suppress deterioration of a storage cell due to heat generation. [Means for solving the problem]

[0006] A spacer according to the present disclosure accommodates an electric storage element and is disposed between adjacent electric storage cells. The spacer includes a plate provided with a plurality of ribs and a heat-conducting member partially filling the gap between the electric storage cell and the plate. When the plate is disposed between the adjacent electric storage cells, the plate includes a first region including a first facing region facing a current collector of the electric storage element and a second facing region facing a central portion of the electric storage element, and a second region including a region located between the first facing region and the second facing region. The plurality of ribs include a first rib defining the first region and the second region, and second ribs provided in the first facing region and the second facing region. When viewed from the arrangement direction in which the adjacent electric storage cells are arranged, in the above-described arrangement, the first region is disposed so as to extend upward from the lower end of the electric storage cell. The heat-conducting member is provided in the first region.

[0007] According to the above configuration, the heat-conducting member is provided in the first region, which includes the first facing region facing the current collector portion where the electric storage element is likely to generate heat and the second facing region facing the central portion, and which is provided so as to extend upward from the lower end side of the electric storage cell. As a result, when a cooler for cooling the electric storage cell is provided at the bottom of the electric storage cell, the heat-conducting member, which is provided over a relatively wide area corresponding to the region where the temperature of the electric storage cell becomes high, can efficiently conduct heat from the electric storage cell to the cooler. As a result, deterioration of the electric storage cell due to heat generation can be suppressed.

[0008] In the spacer according to the present disclosure, the second region may not be provided with the heat-conducting member, and the region located between the first opposing region and the second opposing region may not be provided with the rib.

[0009] According to the above configuration, the expansion of the energy storage cell is permitted by the region located between the first opposing region and the second opposing region, and the electrolyte can be retained in the portion of the energy storage cell that is permitted to expand, thereby suppressing high-rate degradation.

[0010] In the spacer according to the present disclosure, the first opposing region and the second opposing region may be provided so as to narrow toward the lower end of the energy storage cell in the arranged state.

[0011] According to the above configuration, the area between the first facing area and the second facing area can be widened. This area allows the expansion of the storage cell, and by widening the portion of the storage cell that is allowed to expand, more electrolyte can be retained. As a result, high-rate degradation can be effectively suppressed. [Effects of the Invention]

[0012] According to the present disclosure, it is possible to provide a spacer that can suppress deterioration of a power storage cell due to heat generation. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view of an electricity storage module according to an embodiment. [Figure 2] FIG. 2 is a diagram for explaining a detailed configuration of a storage cell according to an embodiment. [Figure 3] FIG. 2 is a front view of the spacer according to the embodiment. [Figure 4] 10A to 10C are diagrams for explaining the function of a spacer according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

[0015] 1 is a schematic cross-sectional view of an electricity storage device according to an embodiment. Referring to FIG. 1, an electricity storage module 100 according to the embodiment will be described.

[0016] As shown in FIG. 1, the energy storage module 100 includes an energy storage stack 1, a heat transfer member 50, and a cooler 60.

[0017] The energy storage stack 1 includes a plurality of energy storage cells 10 and a plurality of spacers 20, 20A, and 20B. The spacers 20, 20A, and 20B and the energy storage cells 10 are arranged alternately in a predetermined arrangement direction (DR1 direction). The spacers 20, 20A, and 20B are made of, for example, an insulating member.

[0018] The spacer 20A is arranged at one end of the energy storage stack 1 in the arrangement direction. The spacer 20B is arranged at the other end of the energy storage stack 1 in the arrangement direction. A plurality of energy storage cells 10 and a plurality of spacers 20 are arranged between the spacer 20A and the spacer 20B. The spacer 20 is arranged between the energy storage cells 10 adjacent to each other in the arrangement direction. The spacer 20 includes a plate 30 and a heat conduction member 40. A detailed configuration of the spacer 20 will be described later with reference to FIG. 3.

[0019] The heat conducting member 50 is disposed between the power storage stack 1 and the cooler 60. More specifically, the heat conducting member 50 is disposed between the bottom surface of the power storage stack 1 and the top surface of the cooler 60. The heat conducting member 50 is made of, for example, grease or the like having thermal conductivity.

[0020] The cooler 60 is disposed below the power storage stack 1. The cooler 60 cools the power storage stack 1. The cooler 60 is configured, for example, so that a refrigerant flows inside the cooler 60. The cooler 60 may be of an air-cooled type or a liquid-cooled type.

[0021] 2 is a diagram for explaining the detailed configuration of the storage cell according to the embodiment. The configuration of the storage cell 10 will be described with reference to FIG.

[0022] 2, the energy storage cell 10 is, for example, a rechargeable secondary battery such as a lithium ion battery. The energy storage cell 10 includes a housing case 11, an electrode assembly 14 as an energy storage element, a positive electrode external terminal 17, a negative electrode external terminal 18, insulators 191 and 192, and current collecting members 193 and 194.

[0023] The storage case 11 includes a storage section 12 in the shape of a bottomed square cylinder, and a sealing plate 13 that seals the opening of the storage section 12. The storage case 11 contains an electrode assembly 14 and an electrolyte solution therein. A positive electrode external terminal 17 and a negative electrode external terminal 18 are provided on the outside of the storage case 11. Specifically, the positive electrode external terminal 17 and the negative electrode external terminal 18 are attached to the sealing plate 13. The positive electrode external terminal 17 and the negative electrode external terminal 18 are arranged side by side in the width direction (W direction). The width direction is a direction perpendicular to the arrangement direction (DR1 direction) and the up-down direction (T direction).

[0024] The insulator 191 electrically insulates the positive electrode external terminal 17 from the casing 11. The insulator 192 electrically insulates the negative electrode external terminal 18 from the casing 11. The insulators 191 and 192 are arranged on the sealing plate 13.

[0025] The electrode body 14 has a positive electrode plate, a negative electrode plate, and a separator (none of which are shown), and the positive electrode plate and negative electrode plate are wound around a winding axis with the separator interposed between them. The positive electrode plate has a metal foil and a positive electrode active material layer provided on the surface of the metal foil. The negative electrode plate has a metal foil and a negative electrode active material layer provided on the surface of the metal foil. A positive electrode current collector 15 and a negative electrode current collector 16 are provided on both ends of the electrode body 14 in the winding axis direction, respectively. The electrode body 14 is housed in the housing case 11 so that the winding axis direction is parallel to the width direction.

[0026] The positive electrode current collector 15 is formed by bundling uncoated portions of the metal foil of the positive electrode plate that are not coated with a positive electrode active material layer, while the negative electrode current collector 16 is formed by bundling uncoated portions of the metal foil of the negative electrode plate that are not coated with a negative electrode active material layer.

[0027] In this embodiment, the electrode assembly 14 will be described as a so-called wound electrode assembly, but is not limited to this. The electrode assembly 14 may also be a laminated electrode assembly in which positive and negative electrode plates are stacked with a separator interposed therebetween. In this case, the positive electrode current collector 15 is formed by bundling positive electrode tabs provided on the positive electrode plates, and the negative electrode current collector 16 is formed by bundling negative electrode tabs provided on the negative electrode plates.

[0028] The current collecting member 193 electrically connects the positive electrode current collecting portion 15 and the positive electrode external terminal 17. The current collecting member 193 is electrically insulated from the casing 11 (specifically, the sealing plate 13) by an insulator (not shown).

[0029] The current collecting member 194 electrically connects the negative electrode current collecting portion 16 and the negative electrode external terminal 18. The current collecting member 194 is electrically insulated from the casing 11 (specifically, the sealing plate 13) by an insulator (not shown).

[0030] The bottom of the housing 11 is thermally connected to the cooler 60 via the heat conducting member 50. Furthermore, as shown in FIG. 1 again, the heat conducting member 40 also abuts against the heat conducting member 50. As a result, the side surface of the housing 11 in contact with the heat conducting member 40 is also thermally connected to the cooler 60 via the heat conducting member 40 and the heat conducting member 50.

[0031] 3 is a front view of the spacer according to the embodiment, and the spacer 20 will be described in detail with reference to FIG.

[0032] As shown in FIG. 3 , the plate 30 is provided with a plurality of ribs (a first rib 32 and second ribs 34, 35, and 36, which will be described later). The plate 30 has a generally plate-like shape. The plate 30 has a front surface 30a and a back surface 30b. The front surface 30a faces one side of the arrangement direction when the plate 30 is arranged between adjacent energy storage cells 10. The back surface 30b faces the other side of the arrangement direction when the plate 30 is arranged as described above. A plurality of ribs are provided on each of the front surface 30a and the back surface 30b.

[0033] In the above-described arrangement, the plate 30 includes a first region R1 including a first opposing region R10 facing the current collecting portions (positive electrode current collecting portion 15 and negative electrode current collecting portion 16) of the electrode body 14 and a second opposing region R20 facing the center of the electrode body 14, and a second region R2 including regions R3 and R4 located between the first opposing region R10 and the second opposing region R20.

[0034] The first opposing region R10 includes a region R11 opposing the positive electrode current collector 15 and a region R12 corresponding to the negative electrode current collector 16. The second region R2 further includes a region R5 located outside a side rib 321 (described later) and a region R6 located outside a side rib 322. The region R3 is located between the region R11 and the second opposing region R20, and the region R4 is located between the region R12 and the second opposing region R20.

[0035] The plurality of ribs include a first rib 32 that defines the first region R1 and the second region R2, and second ribs 35, 36, 34 that are provided in the first opposing region R10 and the second opposing region R20.

[0036] The first rib 32 includes side ribs 321, 322 and inner ribs 323 to 326. The side ribs 321, 322 and the inner ribs 323 to 326 are arranged side by side in the width direction.

[0037] The side rib 321 is disposed on one side in the width direction. For example, in the above-described arrangement, the side rib 321 is disposed so as to overlap the positive electrode current collecting portion 15. The side rib 322 is disposed on the other side in the width direction. In the above-described arrangement, the side rib 322 is disposed so as to overlap the negative electrode current collecting portion 16.

[0038] The side ribs 321, 322 define both ends of the first region R1 in the width direction. The side ribs 321, 322 extend substantially parallel to the up-down direction (direction T). In the above-described arrangement, the side ribs 321, 322 are provided so as to extend upward from the lower end 10b (see FIG. 1 ) of the energy storage cell 10 when viewed from the arrangement direction. When viewed from the arrangement direction, the upper ends of the side ribs 321, 322 are located above the positive electrode current collector 15 and the negative electrode current collector 16. More specifically, the upper ends of the side ribs 321, 322 are located between the positive electrode current collector 15, the negative electrode current collector 16, and the sealing plate 13.

[0039] The inner ribs 323 to 326 are disposed between the side ribs 321 and 322 .

[0040] When viewed from the arrangement direction in the above-described arrangement state, the inner ribs 323, 324 extend upward from the lower end 10b of the energy storage cell 10. The inner rib 323 is disposed closer to the side rib 321 than the inner rib 324.

[0041] The inner ribs 323, 324 are arranged in an inverted V shape. The inner rib 323 is inclined so as to move away from the side rib 321 as it extends upward. The inner rib 324 is inclined so as to move closer to the side rib 321 as it extends upward. The upper ends of the inner ribs 323 and 324 are connected at a position lower than the upper ends of the side ribs 321, 322. The above-mentioned region R3 is formed between the inner rib 323 and the inner rib 324.

[0042] The inner ribs 325, 326 are arranged between the inner rib 324 and the side rib 322. When viewed from the arrangement direction in the above-mentioned arrangement state, the inner ribs 325, 326 extend upward from the lower end portions 10b of the energy storage cells 10. The inner rib 325 is arranged closer to the side rib 322 than the inner rib 326.

[0043] The inner ribs 325, 326 are arranged in an inverted V shape. The inner rib 325 is inclined so as to move away from the side rib 322 as it extends upward. The inner rib 326 is inclined so as to move closer to the side rib 322 as it extends upward. The upper ends of the inner ribs 325 and 326 are connected at a position lower than the upper ends of the side ribs 321, 322. The above-mentioned region R4 is formed between the inner ribs 325 and 326.

[0044] A region R11 that constitutes a part of the first facing region R10 is formed between the side rib 321 and the inner rib 323. A region R12 that constitutes a part of the first facing region R10 is formed between the side rib 322 and the inner rib 325. The first facing region R10 (more specifically, the regions R11, R12) is provided so that the region narrows downward. The first facing region R10 is provided so that the region narrows toward the lower end 10b of the energy storage cell 10 in the above-mentioned arrangement state. A second facing region R20 is formed between the inner rib 324 and the inner rib 326.

[0045] The second ribs 34 are provided in the second opposing region R20. The second ribs 34 are arranged in a line at intervals in the up-down direction. Each of the second ribs 34 extends in the width direction. The second ribs 34 are provided so as to be able to press against the center of the energy storage cell 10.

[0046] The second ribs 35 are provided in the region R11. The second ribs 35 are arranged in a line at intervals in the up-down direction. The second ribs 35 extend in the width direction. The second ribs 35 are provided so as to be able to press the energy storage cells 10 in portions corresponding to the positive electrode current collector portions 15. Ends of the second ribs 35 located on one side in the width direction (the side of the side rib 321) overlap the positive electrode current collector portions 15 when viewed from the arrangement direction in the above-mentioned arrangement state.

[0047] The second ribs 36 are provided in the region R12. The second ribs 36 are arranged in a line at intervals in the up-down direction. The second ribs 35 extend in the width direction. The second ribs 35 are provided so as to be able to press the portions of the energy storage cells 10 corresponding to the negative electrode current collecting portions 16. The ends of the second ribs 35 located on the other side in the width direction (the side of the side rib 322) overlap the positive electrode current collecting portions 15 when viewed from the arrangement direction in the above-mentioned arrangement state.

[0048] The heat conducting member 40 partially fills the gap between the energy storage cell 10 and the plate 30. The heat conducting member 40 is provided in the first region R1. When viewed from the arrangement direction in the above-mentioned arrangement state, the first region R1 is provided so as to extend upward from the lower end 10b of the energy storage cell 10. When viewed from the arrangement direction in the above-mentioned arrangement state, the upper end of the heat conducting member 40 is located between the positive electrode current collecting portion 15 and the negative electrode current collecting portion 16 and the sealing plate 13, and overlaps with a portion of the current collecting members 193, 194. The heat conducting member 40 is made of thermally conductive grease or the like.

[0049] The second region R2 (more specifically, regions R3 to R5) is not provided with the heat conduction member 40. Furthermore, the second region R2 is not provided with ribs.

[0050] Spacers 20A and 20B have a configuration almost identical to that of spacer 20, but spacer 20A has ribs (first and second ribs) only on the back surface 30b side, while spacer 20B has ribs (first and second ribs) only on the front surface 30a side.

[0051] Fig. 4 is a diagram for explaining the function of the spacer according to the embodiment. In Fig. 4, regions R35 to R38 in the energy storage cell 10 where the temperature increases are indicated by dashed lines, a central portion R34 of the energy storage cell 10 is indicated by a two-dot chain line, and expansion regions R41 and R42 of the energy storage cell 10 are indicated by a one-dot chain line.

[0052] In the energy storage cell 10, current tends to concentrate in the positive electrode current collector 15, the negative electrode current collector 16, and the current collectors 193 and 194, which tend to generate a lot of heat. As a result, as indicated by the dashed lines, the temperatures tend to rise in regions R35, R36, R37, and R38 corresponding to the positive electrode current collector 15, the negative electrode current collector 16, and the current collectors 193 and 194.

[0053] As described above, by providing the heat conduction member 40 in the first region R1, heat from the regions R35, R36, R37, and R38 can be efficiently conducted to the cooler 60 via the heat conduction member 40 and the heat conduction member 50. In particular, by providing the heat conduction member 40 in the first facing region R10, it is possible to concentrate and cool the portions of the energy storage cells 10 that are likely to become hot. This makes it possible to suppress a temperature rise in the energy storage cells 10 compared to when the heat conduction member 40 is provided over the entire area of ​​the spacer.

[0054] In addition, since the heat conductive member 40 is provided over a relatively wide range such as the first facing region R10 and the second facing region 20, it is possible to suppress temperature variations in the energy storage cells 10. In this case, if grease is used as the heat conductive member 40, it is possible to increase the adhesion between the heat conductive member 40 and the energy storage cells, thereby more effectively suppressing temperature variations.

[0055] As described above, the spacer 20 according to the embodiment can suppress deterioration of the storage cells 10 due to heat generation, and can improve the capacity of the storage cells 10.

[0056] Furthermore, the second ribs 34, 35, 36 press the energy storage cells 10 so as to suppress expansion in the portions corresponding to the current collecting portions and central portions of the energy storage cells 10, thereby making it possible to suppress deposition of Li.

[0057] Furthermore, as described above, since no ribs are provided in the second region R2, the regions R3 and R4 located between the first opposing region R10 and the second opposing region R20 can allow expansion of the energy storage cell 10 as shown in the regions R41 and R42. By retaining the electrolyte in the expansion regions R41 and R42 that expand partially at positions toward the center of the energy storage cell 10 in this manner, high-rate degradation can be suppressed.

[0058] Furthermore, by narrowing the first facing region R10 and the second facing region R20 downward, the regions R3 and R4 located between the first facing region R10 and the second facing region R20 can be widened. This widens the expansion regions R41 and R42 in the energy storage cell 10 where expansion is permitted, allowing more electrolyte to be retained. As a result, high-rate degradation can be further suppressed.

[0059] (Other variations) In the above description, the power storage module 100 is provided with the cooler 60, but the present invention is not limited to this. A heat dissipation mechanism may be provided instead of the cooler 60.

[0060] The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0061] 1 Energy storage stack, 10 Energy storage cell, 10b Lower end, 11 Housing case, 12 Housing portion, 13 Sealing plate, 14 Electrode body, 15 Positive electrode current collecting portion, 16 Negative electrode current collecting portion, 17 Positive electrode external terminal, 18 Negative electrode external terminal, 20, 20A, 20B Spacer, 30 Plate, 30a Front surface, 30b Back surface, 32 First rib, 34, 35, 36 Second rib, 40 Heat conducting member, 50 Heat conducting member, 60 Cooler, 100 Energy storage module, 191, 192 Insulator, 193, 194 Current collecting member, 321, 322 Side rib, 323, 324, 325, 326 Inner rib, R1 First region, R2 2nd area, R3, R4, R5, R6, R11, R12, R35, R36, R37, R38 area, R10 first opposing area, R20 second opposing area, R34 center, R41, R42 expansion area.

Claims

1. A spacer that accommodates a storage element and is disposed between adjacent storage cells, a plate provided with a plurality of ribs; a heat conduction member that partially fills a gap between the storage cell and the plate, When the plate is disposed between the adjacent energy storage cells, the plate includes a first region including a first opposing region facing a current collecting portion of the energy storage element and a second opposing region facing a central portion of the energy storage element, and a second region including a region located between the first opposing region and the second opposing region, the plurality of ribs include a first rib defining the first region and the second region, and a second rib provided in the first opposing region and the second opposing region; In the arrangement state, when viewed from an arrangement direction in which the adjacent energy storage cells are arranged, the first region is provided so as to extend upward from a lower end of the energy storage cell, The heat conducting member is provided in the first region.

2. The heat conduction member is not provided in the second region, The spacer according to claim 1 , wherein the rib is not provided in the region located between the first opposing region and the second opposing region.

3. The spacer according to claim 1 , wherein the first facing region and the second facing region are provided so as to narrow toward the lower end of the energy storage cell in the arranged state.

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