Battery pack

Abstract

This application relates to a battery pack, comprising: a housing with two opposing open ends; a base plate assembly connected to the housing to close one of the open ends; a cell assembly connected to the base plate assembly, the cell assembly comprising multiple cells; the base plate assembly comprising a first insulating partition, a support plate, and a base plate stacked along a first direction, the support plate having multiple first hollow areas penetrating its thickness direction, each first hollow area corresponding to a first explosion-proof valve of a cell in the first direction, the support plate and the base plate forming an exhaust space, the first direction being the height direction of the cells; the first insulating partition is configured to be ruptured under the action of thermal runaway gas generated by the cells, thereby allowing the thermal runaway gas to flow through the first hollow areas into the exhaust space. This battery pack can achieve directional discharge of thermal runaway gas and achieve thermoelectric separation, reducing the risk of thermal propagation of cells and ensuring the safety of the battery pack.

Description

Technical Field

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

[0002] With the rapid expansion and development of the new energy market, the market share of new energy vehicles is gradually increasing. Based on this, people are paying more and more attention to and demanding more from the core component of new energy vehicles: the power battery. The power battery not only needs to provide good power performance, but also needs to have extremely superior stability, meaning that even in the event of an emergency, it can ensure the personal safety of passengers.

[0003] However, currently, when a battery cell experiences thermal runaway, the thermal runaway gas generated by the cell carries a large amount of high-temperature gas and impurities and is released indiscriminately, increasing the risk of thermal propagation within the cell. Utility Model Content

[0004] In view of this, embodiments of this application provide a battery pack to solve at least one problem existing in the background art.

[0005] In a first aspect, embodiments of this application provide a battery pack, the battery pack comprising:

[0006] The enclosure includes two opposing open ends;

[0007] A base plate assembly is connected to the housing to close one of the open ends and forms an accommodating cavity with the housing;

[0008] A cell assembly is connected to the base plate assembly and located within the accommodating cavity; the cell assembly includes multiple cells.

[0009] The base plate assembly includes a first insulating partition, a support plate, and a base plate stacked along a first direction. The support plate is provided with a plurality of first hollow areas that penetrate its thickness direction. Each first hollow area is provided in the first direction corresponding to the first explosion-proof valve of the battery cell. The support plate and the base plate form an exhaust space. The first direction is the height direction of the battery cell.

[0010] The first insulating partition is configured to be able to break through under the action of thermal runaway gas generated by the battery cell, thereby allowing the thermal runaway gas to flow through the first hollow area into the exhaust space.

[0011] In conjunction with the first aspect of this application, in an optional embodiment, the first insulating partition is provided with a first weak connection portion in the region corresponding to the first explosion-proof valve in the first direction, and the thickness a of the first weak connection portion is less than the thickness A of the first insulating partition.

[0012] In conjunction with the first aspect of this application, in an optional embodiment, a plurality of the first hollow areas on the support plate are arranged in a regular hexagonal array, and adjacent first hollow areas are separated by connecting ribs to form a honeycomb structure.

[0013] In conjunction with the first aspect of this application, in an optional embodiment, the base plate assembly further includes a second insulating partition, the second insulating partition being disposed on the side of the support plate opposite to the first insulating partition, and the first insulating partition, the support plate, and the second insulating partition being stacked sequentially.

[0014] In conjunction with the first aspect of this application, in an optional embodiment, the second insulating partition is provided with a second weak connection portion, the second weak connection portion being disposed corresponding to the first hollow area in the first direction, and the thickness b of the second weak connection portion being less than the thickness B of the second insulating partition;

[0015] The first weak connection portion and the second weak connection portion are arranged opposite to each other and are configured to be able to be broken through sequentially by the thermal runaway gas generated by the battery cell, so that the thermal runaway gas can flow through the first weak connection portion, the first hollow area, and the second weak connection portion and then enter the exhaust space.

[0016] In conjunction with the first aspect of this application, in an optional embodiment, in the first direction, the surface of the support plate facing the first insulating partition has a first concave structure, the first concave structure matching the outer edge of the first insulating partition to embed the first insulating partition in the first concave structure, and / or the surface of the support plate facing the second insulating partition has a second concave structure, the second concave structure matching the outer edge of the second insulating partition to embed the second insulating partition in the second concave structure.

[0017] In conjunction with the first aspect of this application, in an optional embodiment, the housing is provided with a stepped structure on the side near the bottom plate assembly, and the first insulating partition is connected to the support plate via the stepped structure.

[0018] In conjunction with the first aspect of this application, in an optional embodiment, in the first direction, the housing is provided with a first chamber and a second chamber that are isolated from each other, the first chamber being in communication with the exhaust space, and the second chamber being not in communication with the first chamber;

[0019] The battery pack also includes a second explosion-proof valve, which is located on the outer surface of the housing and communicates with the first chamber.

[0020] In conjunction with the first aspect of this application, in an optional embodiment, in the first direction, the housing is further provided with a third chamber, a fourth chamber and a fifth chamber, the third chamber being connected to the fourth chamber and the first chamber, and the fifth chamber being not connected to the third chamber, the fourth chamber and the second chamber.

[0021] In conjunction with the first aspect of this application, in an optional embodiment, the housing is provided with a plurality of first exhaust holes, the plurality of first exhaust holes communicating with the exhaust space and the first chamber, the plurality of first exhaust holes surrounding the exhaust space; at least some of the first exhaust holes are provided on the side of the stepped structure facing the receiving cavity.

[0022] The battery pack provided in this application embodiment includes a base plate assembly comprising a first insulating partition, a support plate, and a base plate stacked along a first direction. The support plate has multiple first hollow areas extending through its thickness direction. Each first hollow area is corresponding to a first explosion-proof valve of the battery cell in the first direction. An exhaust space is formed between the support plate and the base plate. Thermal runaway gas generated by the battery cell can break through the first insulating partition and flow into the exhaust space, thereby achieving directional discharge of thermal runaway gas and enabling thermoelectric separation, reducing the risk of thermal propagation of the battery cell, and ensuring the safety of the battery pack.

[0023] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0025] Figure 1 This is a three-dimensional structural schematic diagram of the battery pack provided in an embodiment of this application;

[0026] Figure 2 This is an exploded view of the battery pack structure provided in an embodiment of this application;

[0027] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0028] Figure 4 This is another schematic diagram of the battery pack provided in an embodiment of this application;

[0029] Figure 5 This is a cross-sectional schematic diagram of the battery pack provided in an embodiment of this application;

[0030] Figure 6 for Figure 5 Enlarged view of point B in the middle;

[0031] Figure 7 This is a partial cross-sectional schematic diagram of the battery pack provided in an embodiment of this application.

[0032] Figure label:

[0033] 100. Battery pack;

[0034] 10. Housing; 11. Stepped structure; 12. First chamber; 13. Second chamber; 14. Third chamber; 15. Fourth chamber; 16. Fifth chamber; 17. First exhaust port; 18. Isolation plate;

[0035] 20. Base plate assembly; 21. First insulating partition; 211. First weak connection part; 22. Bearing plate; 221. First hollow area; 222. Connecting rib; 223. First concave structure; 23. Base plate; 24. Exhaust space; 25. Second insulating partition; 251. Second weak connection part; 252. Groove;

[0036] 30. Battery cell module; 31. Battery cell; 311. First explosion-proof valve;

[0037] 40. Second explosion-proof valve;

[0038] 50. Liquid cooling assembly; 51. Liquid cooling plate;

[0039] 60. Top cover. Detailed Implementation

[0040] To make the technical solution and beneficial effects of this utility model more apparent and understandable, a detailed description is provided below by listing specific embodiments. The accompanying drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which this application pertains.

[0041] In the description of this utility model, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of simplifying the description of this utility model and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. In other words, they should not be construed as limitations on this utility model.

[0042] In this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating the relative importance of the indicated features or the number of indicated technical features. Therefore, a feature specified as "first" or "second" can explicitly indicate that at least one of those features is included. In the description of this utility model, "multiple" means at least two, such as two, three, etc.; "several" means at least one, such as one, two, three, etc., unless otherwise explicitly specified.

[0043] In this utility model, unless otherwise explicitly defined, the terms "installation," "connection," "linking," "fixing," and "setting," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can also refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0044] In this utility model, unless otherwise explicitly defined, the terms "above," "on top of," "above," "over," "below," "below," "below," or "below" for "first feature above second feature" can refer to direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Furthermore, "above," "above," and "over" for "first feature above second feature" can mean the first feature is directly above or diagonally above the second feature, or simply indicates that the horizontal height of the first feature is higher than the horizontal height of the second feature. Similarly, "below," "below," and "below" for "first feature below second feature" can mean the first feature is directly below or diagonally below the second feature, or simply indicates that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0045] Please refer to Figures 1 to 5 This application provides a battery pack 100, which includes a top cover 60, a housing 10, a bottom plate assembly 20, and a cell assembly 30. The housing 10 has two opposing open ends. The bottom plate assembly 20 and the top cover 60 are respectively connected to the two open ends of the housing 10. The top cover 60, the bottom plate assembly 20, and the housing 10 form a receiving cavity. The cell assembly 30 is connected to the bottom plate assembly 20 and located in the receiving cavity. The cell assembly 30 includes a plurality of cells 31.

[0046] The material of the top cover 60 can be sheet metal or composite material, such as SMC, PCM, or RTM. The top cover 60 can be connected to the housing 10 by bolts, or by other connection methods, which are not limited in this embodiment.

[0047] The frame can be made of 6-series aluminum and sealed by extrusion welding.

[0048] The battery cell 31 is equipped with a first explosion-proof valve 311. The first explosion-proof valve 311 mainly serves to prevent explosions and allow ventilation. When thermal runaway does not occur, the first explosion-proof valve 311 primarily functions to allow ventilation, which can also be understood as regulating the air pressure inside and outside the battery cell 31. In the event of thermal runaway in the battery cell 31, the first explosion-proof valve 311 opens, allowing the gas inside the battery cell 31 to be rapidly discharged, thus preventing accidents such as explosions of the battery pack 100. The first explosion-proof valve 311 can be a pin-type explosion-proof valve or a spring-type explosion-proof valve; this embodiment does not limit the specific type of the first explosion-proof valve 311.

[0049] The base plate assembly 20 includes components along a first direction (i.e., Figure 2 The first insulating partition 21, the support plate 22 and the bottom plate 23 are stacked in the direction of arrow s1 shown in the figure. The support plate 22 is provided with a plurality of first hollow areas 221 that penetrate its thickness direction. Each first hollow area 221 is corresponding to the first explosion-proof valve 311 of the battery cell 31 in the first direction. The support plate 22 and the bottom plate 23 form an exhaust space 24. The first direction is the height direction of the battery cell 31.

[0050] The first insulating partition 21 is configured to be able to break through under the action of thermal runaway gas generated by the battery cell 31, thereby allowing the thermal runaway gas to flow through the first hollow area 221 and enter the exhaust space 24.

[0051] The base plate 23 serves as the bottom protective plate of the battery pack 100, providing protection, sealing, and increasing the overall structural strength of the battery pack 100. The base plate 23 can be a profile plate or a stamped plate, but it is not limited to these. The base plate 23 and the housing 10 can be fixedly connected by friction stir welding or by bolts; this embodiment does not impose specific limitations.

[0052] In this embodiment, the thermal runaway gas generated by the cell 31 breaks through the first insulating partition 21 and enters the exhaust space 24 through the first hollow area 221 of the support plate 22. This enables the directional discharge of the thermal runaway gas and achieves thermoelectric separation, preventing heat spread within the battery pack and ensuring the safety of the battery pack 100.

[0053] In an optional embodiment, the battery pack 100 further includes a liquid cooling assembly 50, which includes a liquid cooling plate 51 located between adjacent cells to cool the cells.

[0054] In an optional embodiment, the first insulating partition 21 may be made of a non-metallic material, such as mica board, epoxy board, or other composite materials. The first insulating partition 21 has good insulation and withstand voltage performance, with an insulation resistance greater than 500MΩ and a leakage current less than 0.1mA. Compared to metallic materials, the non-metallic material used in the first insulating partition 21 provides better thermal insulation performance, offering favorable conditions for heat preservation of the battery cell 31. The first insulating partition 21 can be connected to the carrier plate 22 by bonding or hot pressing.

[0055] In an optional embodiment, the support plate 22 may be made of an alloy material, such as aluminum alloy, with an insulating coating sprayed on its surface. When the thermal runaway gas generated by the battery cell 31 flows through the first hollow area 221, it comes into contact with the support plate 22 and exchanges heat, thereby reducing the gas temperature. Non-metallic materials may also be used to reduce weight; however, this embodiment does not impose specific limitations.

[0056] In one alternative embodiment, please refer to Figure 3 , Figure 5 and Figure 6 The first insulating partition 21 has a first weak connection portion 211 in the area corresponding to the first explosion-proof valve 311 in the first direction. The thickness a of the first weak connection portion 211 is less than the thickness A of the first insulating partition 21.

[0057] The ratio of the thickness a of the first weak connection portion 211 to the thickness A of the first insulating partition 21 is not specifically limited in this embodiment of the application, but can be set according to requirements, for example: 1:2, 3:4.

[0058] A first weak connection portion 211 corresponding to the first explosion-proof valve 311 is provided on the first insulating partition 21. This allows the first explosion-proof valve 311 of the battery cell 31 to be opened smoothly, thereby breaking the first weak connection portion 211 of the first insulating partition 21. This allows the thermal runaway gas generated by the battery cell 31 to be discharged downward through the first insulating partition 21, preventing the gas from spreading laterally. In other embodiments, the first weak connection portion 211 can also be a cross-shaped pre-marked or circular pre-marked structure to ensure that after the first explosion-proof valve 311 is opened, the first weak connection portion 211 breaks preferentially along the marked line. The marking depth can be 60%-90% of the first insulating partition 21, and is not specifically limited here, but can be set according to requirements.

[0059] The first insulating partition 21 may be located on the side of the support plate 22 closer to the upper cover 60, or it may be located on the side of the support plate 22 away from the upper cover 60. This application embodiment does not limit the location of the partition 21.

[0060] In an optional embodiment, the first weak connection portion 211 is a first groove 252 provided on the first insulating partition 21, and the depth of the first groove 252 is less than the thickness of the first insulating partition 21. Of course, the first weak connection portion 211 is not limited to the first groove 252.

[0061] In an optional embodiment, the plurality of first hollow areas 221 provided on the support plate 22 are arranged in a regular hexagonal array, and adjacent first hollow areas 221 are separated by connecting ribs 222, forming a honeycomb structure.

[0062] The support plate 22 is made of aluminum. Utilizing the characteristics of aluminum, such as low density, light weight, high rigidity, strong load-bearing capacity, good performance, and strong impact resistance, it improves the overall performance of the bottom of the battery pack 100. While reducing the weight of the battery pack 100, it can increase space utilization, reduce energy consumption, and improve the driving range of the electrical device. In addition, the honeycomb structure of the support plate 22 also has good buffering and can absorb the energy from bottom impacts and other working conditions, and provides good space utilization for the battery pack 100.

[0063] The density of the honeycomb structure of the bearing plate 22 can be set according to specific needs. The denser the honeycomb structure, the more significant its buffering and energy absorption effects.

[0064] The battery cell 31 can be a cylindrical battery cell 31. In the first direction, the top of the battery cell 31 is provided with a terminal post, and the bottom of the battery cell 31 is provided with an explosion-proof valve, but it is not limited to this. After the battery cell 31 experiences thermal runaway gas, the thermal runaway gas is discharged from the first explosion-proof valve 311 at the bottom of the battery cell 31, breaks through the first weak connection part 211 of the first insulating partition 21, flows through the first hollow area 221 of the support plate 22, and is discharged from the exhaust space 24.

[0065] In one alternative embodiment, please refer to Figure 3 , Figure 5 and Figure 6 The base plate assembly 20 also includes a second insulating partition 25, which is disposed on the side of the support plate 22 away from the first insulating partition 21. The first insulating partition 21, the support plate 22 and the second insulating partition 25 are stacked in sequence.

[0066] A first insulating partition 21 and a second insulating partition 25 are respectively provided on both sides of the bearing plate 22 to achieve multiple protections, avoid the insulation structure failure caused by the continuous impact of high temperature gas on the single-layer insulating partition, and further improve the heat preservation effect of the battery cell 31.

[0067] In an optional embodiment, the second insulating partition 25 is provided with a second weak connection portion 251, which is disposed corresponding to the first hollow area 221 in a first direction. The thickness b of the second weak connection portion 251 is less than the thickness B of the second insulating partition 25. The first weak connection portion 211 is disposed opposite to the second weak connection portion 251 and is configured to be able to be broken through sequentially by the thermal runaway gas generated by the cell 31, so that the thermal runaway gas can flow through the first weak connection portion 211, the first hollow area 221, and the second weak connection portion 251 and then enter the exhaust space 24.

[0068] This can be understood as follows: the thermal runaway gas generated by the battery cell 31 is discharged from the first explosion-proof valve 311, breaks through the first weak connection 211 on the first insulating partition 21, flows through the first hollow area 221 on the support plate 22, breaks through the second weak connection 251 of the second insulating partition 25, and then enters the exhaust space 24. The thermal runaway gas breaks through layer by layer, forming a directional exhaust path, ensuring that the gas under high temperature and pressure is released in an orderly manner through a preset channel, avoiding disordered jetting that could lead to thermal spread to adjacent battery cells.

[0069] In one alternative embodiment, in the first direction, the surface of the support plate 22 facing the first insulating partition 21 is provided with a first concave structure 223, the first concave structure 223 matches the outer edge of the first insulating partition 21 to embed the first insulating partition 21 into the first concave structure 223, and / or the surface of the support plate 22 facing the second insulating partition 25 is provided with a second concave structure (not shown in the figure), the second concave structure matches the outer edge of the second insulating partition 25 to embed the second insulating partition 25 into the second concave structure.

[0070] In this embodiment, embedding the first insulating partition 21 and the second insulating partition 25 into the first concave structure 223 and the second concave structure respectively improves the connection strength between the first insulating partition 21 and the second insulating partition 25 and the support plate 22. Furthermore, it reduces the space occupied by the support plate 22, the first insulating partition 21, and the second insulating partition 25, thereby improving space utilization. Since the first insulating partition 21 and the second insulating partition 25 have the same structure, and the first concave structure 223 and the second concave structure are also the same, a single mold can be used during production, saving mold costs and reducing overall costs. Of course, the structures of the first insulating partition 21 and the second insulating partition 25, as well as the first concave structure 223 and the second concave structure, can also be different.

[0071] In one alternative embodiment, please refer to Figure 7 The enclosure 10 has a stepped structure 11 on the side near the base plate assembly 20, and the first insulating partition 21 is connected to the support plate 22 via the stepped structure 11. The stepped structure 11 provided in the enclosure 10 can reduce the lateral space occupied by the support plate 22 and facilitate the installation between the support plate 22 and the enclosure 10.

[0072] In one alternative embodiment, please refer to Figure 5 and Figure 7 In the first direction (that is, Figure 7 As shown by arrow s1 in the diagram, the housing 10 has a first chamber 12 and a second chamber 13 that are isolated from each other. The first chamber 12 is connected to the exhaust space 24, while the second chamber 13 is not connected to the first chamber 12. The battery pack 100 also includes a second explosion-proof valve 40, which is located on the outer surface of the housing 10 and is connected to the first chamber 12.

[0073] The first chamber 12 and the second chamber 13 are located inside the side beam of the housing 10. When the battery cell 31 generates thermal runaway gas, the thermal runaway gas is discharged from the first explosion-proof valve 311 of the battery cell 31 and flows along... Figure 5 As shown by the arrow, the thermal runaway gas is discharged from the first explosion-proof valve 311 of the cell 31, breaking through the first insulating partition 21, flowing through the first hollow area 221 of the support plate 22, breaking through the second insulating partition 25, entering the exhaust space 24 and flowing to the first chamber 12. Finally, the thermal runaway gas is discharged from the housing 10 from the second explosion-proof valve 40 connected to the first chamber 12.

[0074] The first chamber 12 and the second chamber 13 are not connected, which ensures that thermal runaway gas will not enter the seal between the housing 10 and the top cover 60 through the second chamber 13. This greatly reduces the risk of thermal runaway gas entering the battery pack 100 due to the failure of the seal between the housing 10 and the top cover 60. It also keeps the exhaust channel of the battery pack 100 isolated from the electrical compartment, thereby improving the safety of the battery pack 100.

[0075] In an optional embodiment, in the first direction, the housing 10 is further provided with a third chamber 14, a fourth chamber 15 and a fifth chamber 16. The third chamber 14 is connected to the fourth chamber 15 and the first chamber 12, while the fifth chamber 16 is not connected to the third chamber 14, the fourth chamber 15 and the second chamber 13.

[0076] The fifth chamber 16 is not connected to the third chamber 14, and the second chamber 13, the fifth chamber 16 and other chambers are not connected. It can be understood that the fifth chamber 16 and the second chamber 13 provide double protection to further ensure that thermal runaway gas will not enter the seal between the housing 10 and the top cover 60 through the second chamber 13 and the fifth chamber 16, thus ensuring the isolation effect between the exhaust channel of the battery pack 100 and the electrical compartment, thereby improving the safety of the battery pack 100.

[0077] In addition, the flow of thermal runaway gas through the first chamber 12, the third chamber 14 and the fourth chamber 15 can increase the flow path of the thermal runaway gas, thereby increasing the energy lost by the thermal runaway gas during the flow process and reducing the energy discharged from the second explosion-proof valve 40, thus reducing the degree of harm caused by the thermal runaway gas.

[0078] Furthermore, the third chamber 14, the fourth chamber 15, and the first chamber 12 are separated by an isolation plate 18. The isolation plate 18 is provided with flow holes, through which the thermal runaway gas flows to the second explosion-proof valve 40 and is discharged from the battery pack 100. The isolation plate 18 can block part of the flow of thermal runaway gas, thereby allowing the thermal runaway gas to flow back and forth during the discharge process. During the back and forth flow, energy is lost, thereby reducing the energy of the thermal runaway gas when it is discharged from the second explosion-proof valve 40.

[0079] More chambers can be provided on the housing 10 to further increase the length of the thermal runaway gas flow path. The embodiments of this application do not specifically limit the number of chambers, and can be selected according to needs.

[0080] In one alternative embodiment, please refer to Figure 7 The housing 10 is provided with a plurality of first exhaust holes 17, which are connected to the exhaust space 24 and the first chamber 12. The plurality of first exhaust holes 17 are arranged around the exhaust space 24, and at least some of the first exhaust holes 17 are arranged on the side of the stepped structure 11 facing the receiving cavity.

[0081] Multiple first exhaust ports 17 are arranged around the exhaust space 24, which can improve the discharge efficiency of thermal runaway gas in the exhaust space 24 and avoid the accumulation of a large amount of thermal runaway gas.

[0082] It should be understood that the above embodiments are exemplary and are not intended to encompass all possible implementations included in the claims. Various modifications and changes can be made to the above embodiments without departing from the scope of this disclosure. Similarly, the various technical features of the above embodiments can be arbitrarily combined to form other embodiments of this application that may not be explicitly described. Therefore, the above embodiments only illustrate several implementations of this application and do not limit the scope of protection of this patent application.

Claims

1. A battery pack, characterized in that, The battery pack (100) includes: The housing (10) includes two opposing open ends; The base plate assembly (20) is connected to the housing (10) to close one of the open ends and forms a receiving cavity with the housing (10); A battery cell assembly (30) is connected to the base plate assembly (20) and located within the accommodating cavity, the battery cell assembly (30) comprising a plurality of battery cells (31); The base plate assembly (20) includes a first insulating partition (21), a support plate (22) and a base plate (23) stacked along a first direction. The support plate (22) has a plurality of first hollow areas (221) penetrating its thickness direction. Each first hollow area (221) is corresponding to the first explosion-proof valve (311) of the battery cell (31) in the first direction. The support plate (22) and the base plate (23) form an exhaust space (24). The first direction is the height direction of the battery cell (31). The first insulating partition (21) is configured to be able to break through under the action of thermal runaway gas generated by the battery cell (31), thereby allowing the thermal runaway gas to flow through the first hollow area (221) and enter the exhaust space (24).

2. The battery pack according to claim 1, characterized in that, The first insulating partition (21) has a first weak connection part (211) in the area corresponding to the first explosion-proof valve (311) in the first direction, and the thickness a of the first weak connection part (211) is less than the thickness A of the first insulating partition (21).

3. The battery pack according to claim 1, characterized in that, The first hollow areas (221) on the support plate (22) are arranged in a regular hexagonal array, and adjacent first hollow areas (221) are separated by connecting ribs (222) to form a honeycomb structure.

4. The battery pack according to claim 2, characterized in that, The base plate assembly (20) further includes a second insulating partition (25), which is disposed on the side of the support plate (22) away from the first insulating partition (21). The first insulating partition (21), the support plate (22) and the second insulating partition (25) are stacked in sequence.

5. The battery pack according to claim 4, characterized in that, The second insulating partition (25) is provided with a second weak connection part (251), which is provided in the first direction corresponding to the first hollow area (221). The thickness b of the second weak connection part (251) is less than the thickness B of the second insulating partition (25). The first weak connection portion (211) and the second weak connection portion (251) are arranged opposite to each other and are configured to be able to be broken through in sequence by the thermal runaway gas generated by the battery cell (31), so that the thermal runaway gas can flow through the first weak connection portion (211), the first hollow area (221), and the second weak connection portion (251) and enter the exhaust space (24).

6. The battery pack according to claim 4, characterized in that, In the first direction, the surface of the support plate (22) facing the first insulating partition (21) is provided with a first concave structure (223), the first concave structure (223) matches the outer edge of the first insulating partition (21) to embed the first insulating partition (21) into the first concave structure (223), and / or the surface of the support plate (22) facing the second insulating partition (25) is provided with a second concave structure, the second concave structure matches the outer edge of the second insulating partition (25) to embed the second insulating partition (25) into the second concave structure.

7. The battery pack according to claim 1, characterized in that, The housing (10) has a stepped structure (11) on the side near the bottom plate assembly (20), and the first insulating partition (21) is connected to the bearing plate (22) via the stepped structure (11).

8. The battery pack according to claim 7, characterized in that, In the first direction, the housing (10) is provided with a first chamber (12) and a second chamber (13) that are isolated from each other. The first chamber (12) is connected to the exhaust space (24), and the second chamber (13) is not connected to the first chamber (12). The battery pack (100) also includes a second explosion-proof valve (40), which is located on the outer surface of the housing (10) and communicates with the first chamber (12).

9. The battery pack according to claim 8, characterized in that, In the first direction, the housing (10) is further provided with a third chamber (14), a fourth chamber (15) and a fifth chamber (16). The third chamber (14) is connected to the fourth chamber (15) and the first chamber (12), and the fifth chamber (16) is not connected to the third chamber (14), the fourth chamber (15) and the second chamber (13).

10. The battery pack according to claim 8, characterized in that, The housing (10) is provided with a plurality of first exhaust holes (17), which are connected to the exhaust space (24) and the first chamber (12). The plurality of first exhaust holes (17) surround the exhaust space (24); at least some of the first exhaust holes (17) are located on the side of the stepped structure (11) facing the receiving cavity.

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