Battery pack and energy storage device

Abstract

The application relates to the technical field of energy storage power supply, and particularly discloses a battery pack and an energy storage device. The battery pack comprises a battery cell support and a plurality of battery cells. The battery cell support is provided with at least two assembly grooves which are spaced apart, and each assembly groove comprises at least two sub-assembly grooves which are connected in communication. Each battery cell is assembled in a sub-assembly groove, so that the plurality of battery cells can be separated to form a plurality of battery cell groups. The spacing between adjacent battery cell groups is greater than the spacing between adjacent battery cells in a battery cell group. The battery pack can promote the heat spread of adjacent battery cells in a battery cell group, reduce the risk of a chain reaction caused by thermal runaway of the whole battery pack, and reduce the risk of a battery cell heat spread test failure in the battery pack, thereby improving the success rate of the battery cell heat spread test in the battery pack and meeting the requirements of safety certification regulations.

Description

Technical Field

[0001] This application relates to the field of energy storage power technology, and in particular to a battery pack and energy storage device. Background Technology

[0002] Energy storage devices contain battery packs. When designing battery packs, it is necessary to conduct cell thermal propagation tests on the cells inside. There are also relevant safety certifications in the industry, and the standards are constantly being improved.

[0003] In related technologies, cell thermal runaway testing requires thermal runaway from one thermally runaway cell to trigger thermal runaway in adjacent cells. This test aims to simulate the most common causes of fires in energy storage devices. Currently, in most products in the industry, cell thermal runaway easily leads to a chain reaction during the above test, resulting in test failure and failure to meet safety certification requirements. Utility Model Content

[0004] In view of this, this application provides a battery pack and energy storage device that can not only promote the thermal propagation of the battery cells, but also reduce the risk of a chain reaction in the battery pack that could lead to test failure.

[0005] One embodiment of this application provides a battery pack. The battery pack includes a cell support and a plurality of cells. The cell support has at least two spaced-apart mounting slots, each mounting slot including at least two interconnected sub-mounting slots. Each cell is assembled in one sub-mounting slot, so that the plurality of cells can be separated to form a plurality of cell groups. The spacing between adjacent cell groups is greater than the spacing between adjacent cells in a cell group.

[0006] In the aforementioned battery pack, the smaller spacing (i.e., close proximity) between cells in each cell group improves heat conduction between cells, promoting heat propagation within the battery pack. Conversely, the larger spacing (i.e., more spaced out) between cell groups reduces the risk of the entire battery pack going out of control due to heat propagation from all cells. This improves the success rate of thermal propagation testing for the battery pack, meeting safety certification requirements.

[0007] In some embodiments of this application, the spacing between adjacent cells in the cell assembly is less than 1 mm.

[0008] By limiting the spacing between adjacent cells in each cell group to less than 1mm, better heat conduction between cells can be ensured, which is beneficial for promoting heat propagation. When any cell in a cell group experiences thermal runaway, the heat generated by the runaway cell can be rapidly conducted to adjacent cells, thereby causing thermal runaway in adjacent cells, i.e., heat propagation.

[0009] In some embodiments of this application, the spacing between adjacent battery cell groups is greater than 1 mm.

[0010] By limiting the spacing between adjacent cell groups to more than 1mm, it can be ensured that the cell groups are at a safe distance. This helps to reduce the risk that the entire battery pack will become uncontrollable due to the spacing between cell groups being too small, which could lead to a chain reaction and cause the battery pack's thermal propagation test to fail.

[0011] In some embodiments of this application, each assembly slot contains two sub-assembly slots, which are spaced apart.

[0012] In some embodiments of this application, each assembly slot contains three sub-assembly slots. The three sub-assembly slots are spaced apart, and the center line connecting the three sub-assembly slots forms a straight line, an L-shape, or a triangle.

[0013] In some embodiments of this application, the cell support is further provided with a drain channel, which is configured to connect adjacent sub-assembly channels in each assembly channel.

[0014] When any cell in the battery pack experiences thermal runaway, the leaking trigger electrolyte can flow along the drain channels to adjacent cells, causing thermal runaway in those cells as well—a phenomenon known as thermal propagation within the battery pack. The drain channels help to better facilitate this thermal propagation.

[0015] In some embodiments of this application, the cell support has protruding ribs in each sub-assembly slot. The protruding ribs support the ends of the cell so that the cell support and the cell are spaced apart.

[0016] By setting the ribs, a gap can be formed between the cell support and the cell, reducing the risk that the trigger electrolyte leaking during thermal runaway of the cell cannot be discharged quickly due to the cell support blocking the end of the cell. This is beneficial to promote the thermal spread of the cell.

[0017] In some embodiments of this application, the ribs are configured as an integral structure with the cell support.

[0018] By constructing the ribs as an integral part of the cell support structure, the structural strength of the ribs can be improved, which helps to ensure that the ribs can always stably support the end of the cell. Secondly, the assembly process of the battery pack can be simplified, which helps to improve the assembly efficiency of the battery pack.

[0019] In some embodiments of this application, the cell support includes at least two sub-supports, and the multiple sub-supports are detachably connected, with each sub-support corresponding to an assembly slot.

[0020] During the battery pack manufacturing process, production and installation personnel can assemble multiple sub-frames and cells simultaneously, which helps improve the assembly efficiency of the battery pack. For example, cells and sub-frames can be assembled independently first, and then the sub-frames with assembled cells can be connected to form a battery pack.

[0021] One embodiment of this application provides an energy storage device. The energy storage device includes a housing and a battery pack as described in any of the above embodiments. The battery pack is installed inside the housing.

[0022] The aforementioned energy storage device uses the same battery pack. The smaller spacing (i.e., close proximity) between cells in each cell group improves heat conduction, promoting thermal propagation within the battery pack. Simultaneously, the larger spacing (i.e., more spaced out) between cell groups reduces the risk of the entire battery pack going out of control due to thermal propagation from all cells. This improves the success rate of thermal propagation tests, meeting safety certification requirements. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation on the scope.

[0024] Figure 1 This is a schematic diagram of the structure of an energy storage device provided in an embodiment of this application; Figure 2 This is an exploded view of an energy storage device provided in one embodiment of this application; Figure 3 This is a schematic diagram of the structure of a battery pack provided in one embodiment of this application; Figure 4 This is a schematic diagram of the structure of a battery cell assembly provided in an embodiment of this application; Figure 5 This is an exploded view of a battery cell assembly provided in one embodiment of this application; Figure 6 A schematic diagram of a battery pack in which two cells form a cell group, according to an embodiment of this application; Figure 7 A schematic diagram of the sub-support structure when the number of sub-assembly slots provided in one embodiment of this application is two; Figure 8 A schematic diagram of the sub-support structure is provided in one embodiment of this application when the number of sub-assembly slots is three and the center line connecting the three sub-assembly slots is a straight line. Figure 9 The following is a schematic diagram of the structure of a sub-support when the number of sub-assembly slots provided in one embodiment of this application is three, and the center line connecting the three sub-assembly slots forms an L-shape; Figure 10 A schematic diagram of the sub-support structure is provided when the number of sub-assembly slots provided in one embodiment of this application is three, and the center line connecting the three sub-assembly slots forms a triangle. Figure 11 for Figure 4 The diagram shows a cross-sectional view of the battery cell assembly after it has been cut along line AA.

[0025] Explanation of key component symbols: 100. Energy storage device; 10. Battery pack; 20. Housing; 11. Cell support; 12. Cell; 13. Cell assembly; 111. Assembly slot; 112. Drainage slot; 113. Sub-support; 114. Rib; 1111. Sub-assembly slot; X, First direction; Y, Second direction. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0028] Energy storage devices contain battery packs. When designing battery packs, it is necessary to conduct cell thermal propagation tests on the cells inside. There are also relevant safety certifications in the industry, and the standards are constantly being improved.

[0029] In related technologies, cell thermal runaway testing requires thermal runaway from one thermally runaway cell to trigger thermal runaway in adjacent cells. This test aims to simulate the most common causes of fires in energy storage devices. Currently, in most products in the industry, cell thermal runaway easily leads to a chain reaction during the above test, resulting in test failure and failure to meet safety certification requirements.

[0030] One embodiment of this application provides a battery pack. The battery pack includes a cell support and a plurality of cells. The cell support has at least two spaced-apart mounting slots, each mounting slot including at least two interconnected sub-mounting slots. Each cell is assembled in one sub-mounting slot, so that the plurality of cells can be separated to form a plurality of cell groups. The spacing between adjacent cell groups is greater than the spacing between adjacent cells in a cell group.

[0031] In the aforementioned battery pack, the smaller spacing (i.e., close proximity) between cells in each cell group improves heat conduction between cells, promoting heat propagation within the battery pack. Conversely, the larger spacing (i.e., more spaced out) between cell groups reduces the risk of the entire battery pack going out of control due to heat propagation from all cells. This improves the success rate of cell heat propagation testing, meeting safety certification requirements.

[0032] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0033] Please refer to the following: Figure 1 and Figure 2 One embodiment of this application provides an energy storage device 100. The energy storage device 100 has the functions of storing and discharging electricity, and can be used for household backup power, backup power in production units, outdoor work, outdoor recreation, etc.

[0034] In some embodiments, the energy storage device 100 includes a battery pack 10 and a housing 20. The battery pack 10 is installed inside the housing 20, which isolates the battery pack 10 from the external environment. The battery pack 10 is used to store and supply electricity to the energy storage device 100. The battery pack 10 can also be used as a standalone device to output DC power, or it can be stacked together with an inverter module.

[0035] In some embodiments, the energy storage device 100 includes a power conversion module (not shown) that is electrically connected to the battery pack 10. The power conversion module is used to control the AC / DC conversion of the output current of the battery pack 10. The energy storage device 100 equipped with the power conversion module can be a small portable power supply, a residential energy storage power supply, an industrial or commercial energy storage power supply, or a containerized energy storage power supply, etc.

[0036] In some embodiments, the power conversion module may be omitted. An energy storage device 100 without a power conversion module can be used independently. An energy storage device 100 without a power conversion module typically only outputs DC power. When used independently, an energy storage device 100 without a power conversion module can be used in conjunction with an energy storage device 100 with a power conversion module as a power system providing additional battery capacity.

[0037] Please refer to the following: Figures 3 to 6In some embodiments, the battery pack 10 includes a cell support 11 and a plurality of cells 12. The cell support 11 has at least two spaced-apart mounting slots 111, each mounting slot 111 including at least two interconnected sub-mounting slots 1111. Each cell 12 is mounted in one sub-mounting slot 1111, so that the plurality of cells 12 can be separated to form a plurality of cell groups 13. The spacing between adjacent cell groups 13 is greater than the spacing between adjacent cells 12 in a cell group 13.

[0038] Understandably, during the thermal propagation test of the battery pack 10, when any cell 12 within the battery pack 10 experiences thermal runaway, due to the small spacing between the cells 12 in each cell group 13 (i.e., the cells 12 in each cell group 13 are adjacent to each other), the heat generated by the runaway cell 12 and the triggering electrolyte of the spray valve can be quickly conducted to the adjacent cells 12 in the corresponding cell group 13, thereby triggering thermal runaway in the adjacent cells 12, which in turn promotes thermal propagation in the battery pack 10. The aforementioned triggering electrolyte includes, but is not limited to, electrolyte, high-temperature gas, and burning particles.

[0039] Meanwhile, since the spacing between each cell group 13 is relatively large (that is, each cell group 13 is also far apart from each other), the heat conduction between cell groups 13 is relatively slow, which can prevent heat spread between adjacent cell groups 13 and reduce the risk of the entire battery pack 10 going out of control due to a chain reaction caused by heat spread of all cells 12 in the battery pack 10.

[0040] The battery pack 10 provided in this application can promote the thermal spread of adjacent cells 12 within the cell group 13, while reducing the risk of thermal runaway of the entire battery pack 10 causing a chain reaction that leads to the failure of the thermal spread test of the battery pack 10. This is beneficial to improving the success rate of the thermal spread test of the battery pack 10 and meeting the requirements of safety certification regulations.

[0041] In some embodiments, the spacing between adjacent cells 12 in the cell group 13 is less than 1 mm. By limiting the spacing between adjacent cells 12 in each cell group 13 to less than 1 mm, better heat conduction between cells 12 can be ensured, which is beneficial to better promote heat spread of cells 12.

[0042] Understandably, when any one of the cells 12 in the cell pack 12 experiences thermal runaway, the heat generated by the runaway cell 12 can be rapidly conducted to the adjacent cells 12 in the corresponding cell group 13, thereby causing the adjacent cells 12 to experience thermal runaway, that is, thermal propagation.

[0043] For example, in the cell group 13, the spacing between adjacent cells 12 is 0.5 mm. By limiting the spacing between adjacent cells 12 in each cell group 13 to 0.5 mm, the risk of increased assembly difficulty between the cells 12 and the cell support 11 due to the excessively small spacing between adjacent cells 12 can be reduced.

[0044] In other embodiments, the spacing between adjacent cells 12 in the cell group 13 may also be other suitable sizes. This application does not limit this, and those skilled in the art can choose according to the actual situation.

[0045] In some embodiments, the spacing between adjacent cell groups 13 is greater than 1 mm. By limiting the spacing between adjacent cell groups 13 to greater than 1 mm, it can be ensured that each cell group 13 is at a safe distance, which helps to better reduce the risk that the entire battery pack 10 will run out of control due to the spacing between cell groups 13 being too small, thereby triggering a chain reaction that leads to the failure of the thermal propagation test of the battery pack 10.

[0046] For example, the spacing between adjacent cell groups 13 is 1.5 mm. It should be noted that by limiting the spacing between adjacent cell groups 13 to 1.5 mm, the overall volume of the battery pack 10 can be reduced while meeting the safe distance between each cell group 13, which is beneficial for the miniaturization design of the energy storage device 100.

[0047] In other embodiments, the spacing between adjacent battery cell groups 13 may also be other suitable sizes. This application does not limit this, and those skilled in the art can choose according to the actual situation.

[0048] Please refer to the following: Figure 6 and Figure 7 In some embodiments, each assembly slot 111 contains two sub-assembly slots 1111, which are spaced apart. When a battery cell 12 is assembled into the corresponding sub-assembly slot 1111, every two battery cells 12 form a battery cell group 13.

[0049] Please see Figure 8 In some embodiments, each assembly slot 111 contains three sub-assembly slots 1111. The three sub-assembly slots 1111 are spaced apart, and the center line connecting the three sub-assembly slots 1111 is a straight line. When a battery cell 12 is assembled into the corresponding sub-assembly slot 1111, every three battery cells 12 form a battery cell group 13, and the three battery cells 12 are arranged in a straight line.

[0050] Please see Figure 9In some embodiments, each assembly slot 111 contains three sub-assembly slots 1111. The three sub-assembly slots 1111 are spaced apart, and the center line connecting the three sub-assembly slots 1111 forms an L-shape. When a battery cell 12 is assembled into the corresponding sub-assembly slot 1111, every three battery cells 12 form a battery cell group 13, and the three battery cells 12 are distributed in an L-shape.

[0051] Please see Figure 10 In some embodiments, each assembly slot 111 contains three sub-assembly slots 1111. The three sub-assembly slots 1111 are spaced apart, and the center line connecting the three sub-assembly slots 1111 forms a triangle. When a battery cell 12 is assembled into the corresponding sub-assembly slot 1111, every three battery cells 12 form a battery cell group 13, and the three battery cells 12 are distributed in a triangular pattern.

[0052] Please refer to the following: Figure 5 , Figure 7 and Figure 11 In some embodiments, the cell support 11 is further provided with a drainage groove 112, which is configured to connect adjacent sub-assembly grooves 1111 in each assembly groove 111. The arrangement of the drainage groove 112 is beneficial to better promote the heat spread of the cell 12.

[0053] Understandably, when any cell 12 in the cell pack 13 experiences thermal runaway, the trigger electrolyte leaked from the runaway cell 12 can flow along the drainage groove 112 to the adjacent cell 12, thereby causing the adjacent cell 12 to experience thermal runaway, that is, the battery pack 10 experiences thermal propagation.

[0054] Please refer to the following: Figure 3 , Figure 4 and Figure 7 In some embodiments, the cell support 11 includes at least two sub-supports 113, and the multiple sub-supports 113 are detachably connected, with each sub-support 113 corresponding to an assembly slot 111.

[0055] During the production of the battery pack 10, production and installation personnel can assemble multiple sub-supports 113 and battery cells 12 simultaneously, which helps to improve the assembly efficiency of the battery pack 10. For example, production and installation personnel can first assemble the battery cells 12 and sub-supports 113 independently, and then connect multiple sub-supports 113 equipped with battery cells 12 to form the battery pack 10.

[0056] It is worth noting that there is no order requirement for the "assembly between multiple sub-supports 113" and the "assembly between battery cell 12 and corresponding sub-support 113" in this application. Production and installation personnel can also connect multiple sub-supports 113 to form battery cell support 11 first, and then assemble the battery cell 12 into the corresponding sub-assembly slot 1111. Those skilled in the art can choose according to the actual situation.

[0057] Please refer to the following: Figure 7 and Figure 11 In some embodiments, the cell support 11 has a rib 114 in each sub-assembly slot 111. The rib 114 supports the end of the cell 12 so that the cell support 11 and the cell 12 are spaced apart.

[0058] By setting the rib 114, a gap can be formed between the cell support 11 and the cell 12, reducing the risk that the trigger electrolyte leaked during thermal runaway of the cell 12 cannot be discharged quickly due to the cell support 11 blocking the end of the cell 12, which is conducive to promoting the thermal spread of the cell 12.

[0059] In some embodiments, the rib 114 is configured as an integral part of the cell support 11. This improves the structural strength of the rib 114, ensuring that it can always stably support the end of the cell 12. It also simplifies the assembly process of the battery pack 10, thereby improving the assembly efficiency of the battery pack 10.

[0060] Furthermore, those skilled in the art should recognize that the above embodiments are merely illustrative of this application and are not intended to limit this application. Any appropriate changes and variations made to the above embodiments within the essential spirit and scope of this application fall within the scope of this application's disclosure.

Claims

1. A battery pack, characterized in that, include: The battery cell support has at least two spaced-apart assembly slots, each of which includes at least two interconnected sub-assembly slots. Multiple battery cells are assembled in one of the sub-assembly slots, so that the multiple battery cells can be separated to form multiple battery cell groups; the spacing between adjacent battery cell groups is greater than the spacing between adjacent battery cells in the battery cell group.

2. The battery pack according to claim 1, characterized in that, In the battery cell assembly, the spacing between adjacent battery cells is less than 1 mm.

3. The battery pack according to claim 2, characterized in that, The spacing between adjacent battery cell groups is greater than 1 mm.

4. The battery pack according to claim 1, characterized in that, In each of the assembly slots, there are two sub-assembly slots, and the two sub-assembly slots are distributed at intervals.

5. The battery pack according to claim 1, characterized in that, In each of the assembly slots, there are three sub-assembly slots, which are spaced apart, and the center line connecting the three sub-assembly slots is a straight line, an L-shape, or a triangle.

6. The battery pack according to any one of claims 1 to 5, characterized in that, The cell support is also provided with a drain channel, which is configured to connect adjacent sub-assembly slots in each of the assembly slots.

7. The battery pack according to claim 6, characterized in that, The cell support has a raised rib in each of the sub-assembly slots, and the raised rib supports the end of the cell so that the cell support and the cell are spaced apart.

8. The battery pack according to claim 7, characterized in that, The protruding rib is constructed as an integral part of the battery cell support.

9. The battery pack according to any one of claims 1 to 5, characterized in that, The cell support includes at least two sub-supports, and multiple sub-supports are detachably connected. Each sub-support is provided with a corresponding assembly slot.

10. An energy storage device, characterized in that, It includes a housing and a battery pack as described in any one of claims 1 to 9, wherein the battery pack is installed in the housing.

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