Battery pack and vehicle

Abstract

A battery pack (100) and a vehicle (200). The battery pack (100) comprises at least one first battery module (1), at least one second battery module (2), and a liquid cooling system (3), wherein the second battery module (2) and the first battery module (1) are stacked in a first direction; the liquid cooling system (3) comprises a first liquid cooling plate (31) and a second liquid cooling plate (32); the first liquid cooling plate (31) is located at one end of the first battery module (1) and is located between the first battery module (1) and the second battery module (2); and the second liquid cooling plate (32) is located at the end of the second battery module (2) distant from the first battery module (1).

Description

Battery pack and vehicle

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 28, 2023, with application number 202323617645.3. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a battery pack and a vehicle. Background Art

[0003] The 46-inch large cylindrical battery cell is larger in size, capable of holding more charge, and has higher capacity and energy density. With the serialized production of 46-inch large cylindrical battery cells both domestically and internationally, the design of battery systems based on these cells has become an important research and development direction for new energy vehicle battery systems. SUMMARY OF THE INVENTION

[0004] However, the relevant technologies have not fully considered the thermal safety and liquid cooling requirements of the battery system, and lack effective liquid cooling measures, resulting in the need to improve the thermal safety of the current double-layer battery system based on 46-type large cylindrical cells.

[0005] The present application provides a battery pack. The battery pack includes at least one first battery module, at least one second battery module, and a liquid cooling system. The second battery module and the first battery module are stacked in a first direction to form a double-layer battery module. The liquid cooling system includes a first liquid cooling plate and a second liquid cooling plate. The first liquid cooling plate is located at one end of the first battery module and between the first and second battery modules. The second liquid cooling plate is located at an end of the second battery module away from the first battery module.

[0006] The present application also provides a vehicle, which includes the battery pack described above. Beneficial effects

[0007] The battery cell provided in the present application can form a double-layer battery module by stacking the first battery module and the second battery module. When the battery pack containing the double-layer battery module is installed in a vehicle, the vertical space of the entire vehicle can be fully utilized to meet the vehicle's high energy and long endurance requirements. The first liquid cooling plate and the second liquid cooling plate are respectively attached to the top of the first battery module and the second battery module, and can effectively liquid-cool the locations of the first battery module and the second battery module with higher heat generation during the operation of the battery pack, thereby meeting the liquid cooling requirements of the battery pack and improving the thermal safety of the battery pack.

[0008] The vehicle provided in this application, by providing the battery pack described above, can meet the vehicle's high energy and long endurance requirements and can improve thermal safety performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG1 is an exploded view of a battery pack provided in an embodiment of the present application;

[0010] FIG2 is a perspective view of a battery pack provided in an embodiment of the present application;

[0011] FIG3 is a cross-sectional view taken along line BB in FIG2 ;

[0012] FIG4 is a cross-sectional view taken along line AA in FIG2 ;

[0013] FIG5 is a schematic diagram of a thermal runaway pressure relief process of a second battery module provided in an embodiment of the present application;

[0014] FIG6 is a perspective view of a box provided in an embodiment of the present application;

[0015] FIG7 is a schematic structural diagram of a first liquid cooling plate provided in an embodiment of the present application;

[0016] FIG8 is a schematic structural diagram of a vehicle provided in an embodiment of the present application.

[0017] Description of reference numerals:

[0018] 100. Battery pack; 1. First battery module; 10. First pressure relief chamber; 11. First cell tray; 12. First cell; 13. First integrated busbar; 2. Second battery module; 20. Second pressure relief chamber; 21. Second cell tray; 22. Second cell; 23. Second integrated busbar; 3. Liquid cooling system; 31. First liquid cooling plate; 311. Liquid cooling unit; 312. Connecting unit; 313. Avoidance unit; 32. Second liquid cooling plate; 4. Box; 41. Pressure relief channel; 42. Connecting column; 43. Crossbeam; 5. Box cover; 51. Connecting hole; 6. Module frame; 7. Support assembly; 71. Support beam; 711. Through hole; 8. Thermal insulation assembly;

[0019] 200. Vehicle. Modes for Carrying Out the Invention

[0020] In the description of this application, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0021] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, with the first feature having a higher horizontal height than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly below and obliquely below the second feature, with the first feature having a lower horizontal height than the second feature.

[0022] In the description of this embodiment, terms such as "upper," "lower," "left," "right," "front," and "rear" are used to refer to positions or locations based on the positions or locations shown in the accompanying drawings. These terms are intended to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and do not have any special meanings.

[0023] As shown in Figures 1, 3, and 5, an embodiment of the present application provides a battery pack 100, including at least one first battery module 1, at least one second battery module 2, and a liquid cooling system 3. The second battery module 2 and the first battery module 1 are stacked in a first direction X to form a double-layer battery module.

[0024] By stacking the first battery module 1 and the second battery module 2 in the first direction X to form a double-layer battery module, a battery pack 100 including the double-layer battery module can be formed. When the battery pack 100 is installed in a vehicle, the vertical space of the entire vehicle can be fully utilized to meet the vehicle's high energy and long endurance requirements.

[0025] It should be noted that the battery pack 100 provided in the embodiment of the present application may include only one double-layer battery module or multiple double-layer battery modules. For example, as shown in Figure 1, the battery pack also includes three double-layer battery modules. That is, the three second battery modules 2 are stacked on top of the three first battery modules 1. By including multiple double-layer battery modules in the same battery pack 100, the integration of the battery pack 100 can be improved, further meeting the vehicle's long-range requirements.

[0026] As shown in Figures 1 and 5 , the liquid cooling system 3 includes a first liquid cooling plate 31 and a second liquid cooling plate 32. The first liquid cooling plate 31 is located at one end of the first battery module 1 and between the first battery module 1 and the second battery module 2. The second liquid cooling plate 32 is located at the end of the second battery module 2 away from the first battery module 1.

[0027] Specifically, the first and second liquid cooling plates 31 and 32 are attached to the tops of the first and second battery modules 1 and 2, respectively, thereby effectively cooling the locations of the battery pack 100 that generate the most heat during operation, thereby improving the thermal safety and reliability of the battery pack 100. The tops of the first and second battery modules 1 and 2 refer to the ends of the battery cells of the first and second battery modules 1 and 2 where the tabs are located.

[0028] It should be understood that the exploded view shown in FIG1 is only used to illustrate the components included in the battery pack 100 provided in the embodiment of the present application, and is not used to limit the positional relationship between the various components.

[0029] In some embodiments, the battery pack 100 further includes a box body 4 and a box cover 5. The box body 4 has a receiving cavity, and the first battery module 1, the second battery module 2 and the liquid cooling system 3 are all disposed in the receiving cavity. The box cover 5 covers the box body 4.

[0030] The box body 4 and the box cover 5 form a shell structure that accommodates the first battery module 1, the second battery module 2 and the liquid cooling system 3, which can provide effective protection for the first battery module 1, the second battery module 2 and the liquid cooling system 3 and improve the overall structural stability of the battery pack 100.

[0031] In some embodiments, as shown in Figures 3-5, the first battery module 1 includes a first battery cell tray 11, a plurality of first battery cells 12 and a first integrated busbar 13. The first battery cell tray 11 is arranged at the bottom of the box body 4 and forms a first pressure relief chamber 10 with the box body 4. The plurality of first battery cells 12 are installed in the first battery cell tray 11. The first integrated busbar 13 is arranged on the side of the plurality of first battery cells 12 away from the first battery cell tray 11 and is connected to the plurality of first battery cells 12. The box body 4 is provided with a pressure relief channel 41, and the first pressure relief chamber 10 is respectively connected to the pressure relief channel 41 and the explosion-proof valves of the plurality of first battery cells 12.

[0032] Specifically, the first battery cell tray 11 is arranged in the box body 4, and the first battery cell tray 11 is spaced apart from the bottom of the box body 4, thereby forming a first pressure relief chamber 10; a plurality of holes are opened in the first battery cell tray 11, and the position of each hole corresponds to the position of the explosion-proof valve at the bottom of each first battery cell 12, and a pressure relief channel 41 is opened at the bottom of the box body 4. After the first battery cell tray 11 and the box body 4 form the first pressure relief chamber 10, the first pressure relief chamber 10 is respectively connected to the pressure relief channel 41 and the explosion-proof valves of the plurality of first battery cells 12; when thermal runaway occurs in one or more of the first battery cells 12, the pressure relief gas can be released into the first pressure relief chamber 10 through the explosion-proof valve of the first battery cell 12, and then released to the outside of the battery pack 100 through the pressure relief channel 41 connected to the first pressure relief chamber 10.

[0033] Exemplarily, as shown in Figures 3 and 5, the battery pack 100 includes three first battery modules 1, each of which has the same structure and includes a first battery cell tray 11, multiple first battery cells 12 and a first integrated busbar 13; the three first battery cell trays 11 are arranged at intervals in the box body 4, forming a first pressure relief chamber 10 with the box body 4, and a pressure relief channel 41 is opened at the bottom circumferential position of the box body 4. The first pressure relief chamber 10 is connected to the outside through the pressure relief channel 41 for releasing the pressure relief gas.

[0034] In some embodiments, as shown in Figures 3-5, the battery pack 100 further includes a module frame 6, which is disposed above the first liquid cold plate 31. The second battery module 2 includes a second cell tray 21, a plurality of second cells 22, and a second integrated busbar 23. The second cell tray 21 is disposed on a side of the module frame 6 away from the first liquid cold plate 31, and the second cell tray 21 and the module frame 6 form a second pressure relief chamber 20. A plurality of second cells 22 are installed in the second cell tray 21. The second integrated busbar 23 is disposed on a side of the plurality of second cells 22 away from the second cell tray 21 and is connected to the plurality of second cells 22.

[0035] A support assembly 7 is provided between the first battery cell tray 11 and the module frame 6 , and a through hole 711 is opened in the support assembly 7 ; the first pressure relief chamber 10 and the second pressure relief chamber 20 are connected through the through hole 711 , and the second pressure relief chamber 20 is connected to the explosion-proof valves of the plurality of second battery cells 22 .

[0036] Among them, the support component 7 can support the module frame 6 and the second battery module 2 located above the module frame 6. At the same time, the support component 7 is provided with a longitudinal through hole 711, through which the first pressure relief chamber 10 and the second pressure relief chamber 20 can be connected; a plurality of holes are also provided in the second battery cell tray 21, and the position of each hole corresponds to the position of the explosion-proof valve of each second battery cell 22. When one or more of the second battery cells 22 experience thermal runaway, the pressure relief gas can be released into the second pressure relief chamber 20 through the explosion-proof valve at the bottom of the second battery cell 22, and then enter the first pressure relief chamber 10 through the through hole 711 in the support component 7, and finally released to the outside of the battery pack through the pressure relief channel 41 connected to the first pressure relief chamber 10.

[0037] For example, as shown in Figures 3 and 4, the support assembly 7 includes multiple support beams 71, which are respectively arranged at the four corners and the middle portion of the length direction of the first battery cell tray 11, and can provide good support for the module frame 6 and the second battery module 2. Each support beam 71 has a through hole 711 in the vertical direction, and the first pressure relief chamber 10 and the second pressure relief chamber 20 are connected through the through hole 711. Among them, the module frame 6 can be an aluminum alloy module frame.

[0038] Figure 5 is a schematic diagram of the pressure relief process when thermal runaway occurs in the second battery cell 22 of the second battery module 2. The arrows in the figure indicate the flow direction of the pressure relief gas. When thermal runaway occurs in one of the second battery cells 22, the pressure relief gas is released from the explosion-proof valve of the second battery cell 22, enters the second pressure relief chamber 20 through the corresponding hole in the second battery cell tray 21, enters the first pressure relief chamber 10 through the through hole 711 in the support assembly 7, and is finally released out of the battery pack 100 through the pressure relief channel 41 connected to the first pressure relief chamber 10.

[0039] In the embodiment of the present application, a first pressure relief chamber 10 and a second pressure relief chamber 20 are respectively connected to the explosion-proof valves of the first battery cell 12 and the second battery cell 22, and the second pressure relief chamber 20 is connected to the first pressure relief chamber 10, and the first pressure relief chamber 10 is connected to the outside through a pressure relief channel 41 provided on the box body 4, thereby forming a relatively sealed pressure relief space. When thermal runaway occurs in the battery cell, gas-electric isolation can be achieved to prevent the pressure relief gas from affecting other components in the battery pack 100, thereby further improving the thermal safety performance of the battery pack 100.

[0040] In some embodiments, as shown in Figure 5, the battery pack 100 also includes a thermal insulation component 8, which is located between the first liquid cooling plate 31 and the second battery module 2, and / or the thermal insulation component is located on the side surface of the second liquid cooling plate 32 facing away from the second battery module 2.

[0041] The thermal insulation assembly 8 can effectively isolate the gas released during thermal runaway. For example, when the second battery module 2 experiences thermal runaway, the thermal insulation assembly 8 can prevent the depressurized gas generated by the second battery module 2 from damaging the first liquid cooling plate 31 and the first battery module 1 located below.

[0042] Exemplarily, as shown in FIG5 , the heat insulation assembly 8 is located between the first liquid cooling plate 31 and the second battery module 2 and is attached to the surface of the first liquid cooling plate 31 to isolate the heat generated by the second battery module 2 during operation or thermal runaway.

[0043] In some embodiments, the thermal insulation component 8 is a mica board, which has excellent high temperature resistance and can improve the thermal insulation effect.

[0044] In some embodiments, the battery pack 100 further includes a first thermally conductive structural adhesive layer and a second thermally conductive structural adhesive layer. The first thermally conductive structural adhesive layer is disposed between the first liquid cooling plate 31 and the first battery module 1 , and the second thermally conductive structural adhesive layer is disposed between the second liquid cooling plate 32 and the second battery module 2 .

[0045] That is to say, the first liquid cooling plate 31 and the first battery module 1 are fixedly connected by the first heat-conducting structural adhesive layer, and the second liquid cooling plate 32 and the second battery module 2 are fixedly connected by the second heat-conducting structural adhesive, which can improve the stability of the connection while ensuring the thermal conductivity of the liquid cooling plate.

[0046] In some embodiments, as shown in FIG7 , the first liquid cooling plate 31 and the second liquid cooling plate 32 are provided with an avoidance portion 313 , and the avoidance portion 313 corresponds to the position of the components in the box body 4 ; and / or, the avoidance portion 313 corresponds to the position of the components of the box cover 5 .

[0047] Specifically, the avoidance portion 313 includes at least one of various forms such as protrusion, depression and hollowing. By providing the avoidance portion 313, the first liquid cooling plate 31 and the second liquid cooling plate 32 can be prevented from interfering with components in the box body 4 and the box cover 5.

[0048] In some embodiments, a plurality of connecting posts 42 are provided in the box body 4 , and connecting holes 51 are opened in the box cover 5 at positions corresponding to the connecting posts 42 , and the connecting posts 42 are inserted into the connecting holes 51 , and the positions of the avoidance portions 313 and the connecting posts 42 correspond to each other.

[0049] For example, the multiple connecting columns 42 provided in the box body 4 are internal threaded columns, and the box cover 5 is provided with connecting holes 51 at corresponding positions. The box cover 5 and the box body 4 can be fixedly connected by bolts, thereby improving the stability of the overall structure.

[0050] 6 , two crossbeams 43 are provided in the middle of the height direction of the box body 4, and two connecting posts 42 are provided on each crossbeam 43. The connecting posts 42 and the connecting holes 51 cooperate to form a middle ceiling structure, which can be used to lift the battery pack 100.

[0051] Furthermore, when the battery pack 100 includes multiple first battery modules 1 and multiple second battery modules 2, the first liquid cooling plate 31 and the second liquid cooling plate 32 need to cover the multiple first battery modules 1 and the second battery modules 2, respectively. As shown in Figure 7, taking the first liquid cooling plate 31 as an example, the first liquid cooling plate 31 includes a liquid cooling portion 311 and a connecting portion 312. The liquid cooling portion 311 is provided with a liquid cooling flow channel. Each liquid cooling portion 311 can effectively cover one of the first battery modules 1, thereby improving the heat dissipation capacity of the first battery module 1. The connecting portion 312 is used to connect two adjacent liquid cooling portions 311. The avoidance portion 313 is provided in the connecting portion 312 and is hollowed out to avoid the position of the connecting column 42 to avoid interference with the connecting column 42.

[0052] That is, the avoidance portion 313 in the first liquid cooling plate 31 avoids the position of the connecting column 42 , and a hollow is formed at the position corresponding to the connecting column 42 , thereby avoiding interference between the first liquid cooling plate 31 and the connecting column 42 .

[0053] It should be noted that if other components in the battery pack 100 interfere with the first and / or second liquid cooling plates 31 and 32, other relief portions 313 may be provided at the corresponding locations where interference occurs. For example, relief portions 313 may be provided at locations corresponding to the support assembly 7 in the first liquid cooling plate 31. In some embodiments, the first and second battery cells 12 and 22 are 46-inch large cylindrical cells.

[0054] The 46-type large cylindrical battery cell is larger in size, can hold more charge, and has higher capacity and energy density. Exemplarily, the 46-type large cylindrical battery cell includes at least one of the 4680 battery cell, the 4695 battery cell, and the 46120 battery cell.

[0055] In a second aspect, as shown in FIG8 , an embodiment of the present application provides a vehicle 200 comprising the battery pack 100 as described above.

[0056] In an embodiment of the present application, a battery pack 100 including a double-layer battery module can be formed by stacking the first battery module 1 and the second battery module 2. When the battery pack 100 is installed in the vehicle 200, the Z-direction space of the entire vehicle can be fully utilized to meet the high energy and long endurance requirements of the vehicle 200. A first liquid cooling plate 31 and a second liquid cooling plate 32 are respectively provided on the top of the first battery module 1 and the second battery module 2, which can effectively liquid-cool the first battery module 1 and the second battery module 2 during operation of the battery pack, meet the liquid cooling requirements of the battery pack 100, improve the thermal safety and reliability of the battery pack 100, and thus improve the safety of the vehicle 200.

Claims

1. A battery pack comprising at least one first battery module, at least one second battery module and a liquid cooling system; The second battery module and the first battery module are stacked in a first direction to form a double-layer battery module; The liquid cooling system comprises a first liquid cooling plate and a second liquid cooling plate; The first liquid cooling plate is located at one end of the first battery module and between the first battery module and the second battery module; The second liquid cooling plate is located at an end of the second battery module away from the first battery module.

2. The battery pack according to claim 1, further comprising a box body and a box cover; The first battery module, the second battery module and the liquid cooling plate are all arranged in the box; The box cover is covered on the box body.

3. The battery pack according to claim 2, wherein, The first battery module includes a first battery cell tray, a plurality of first battery cells and a first integrated busbar; The first battery cell tray is disposed at the bottom of the box body and forms a first pressure relief chamber with the box body; A plurality of the first battery cells are installed on the first battery cell tray; The first integrated busbar is disposed on a side of the plurality of first battery cells away from the first battery cell tray and is connected to the plurality of first battery cells; The box body is provided with a pressure relief channel, and the first pressure relief chamber is respectively connected with the pressure relief channel and the explosion-proof valves of the first battery cells.

4. The battery pack according to claim 3, further comprising a module frame, wherein the module frame is disposed between the first liquid cooling plate and the second battery module; The second battery module includes a second battery cell tray, a plurality of second battery cells and a second integrated busbar; The second battery cell tray is arranged on a side of the module frame away from the first liquid cooling plate, and the second battery cell tray and the module frame form a second pressure relief chamber; A plurality of the second battery cells are installed on the second battery cell tray; The second integrated busbar is disposed on a side of the plurality of second battery cells away from the second battery cell tray and is connected to the plurality of second battery cells; A support assembly is provided between the first battery cell tray and the module frame, and a through hole is provided in the support assembly; the first pressure relief chamber and the second pressure relief chamber are connected through the through hole, and the second pressure relief chamber is connected with explosion-proof valves of the plurality of second battery cells.

5. The battery pack according to claim 4, wherein, The support assembly includes a plurality of support beams, and the through holes are opened on the support beams.

6. The battery pack according to any one of claims 1-5, further comprising a thermal insulation component, wherein the thermal insulation component is located between the first liquid cooling plate and the second battery module, and / or the thermal insulation component is located on a side surface of the second liquid cooling plate away from the second battery module.

7. The battery pack according to claim 6, wherein, The heat insulation component is a mica board.

8. The battery pack according to any one of claims 1 to 7, further comprising a first thermally conductive structural adhesive layer and a second thermally conductive structural adhesive layer; The first heat-conductive structural adhesive layer is disposed between the first liquid cooling plate and the first battery module; The second heat-conductive structural adhesive layer is arranged between the second liquid cooling plate and the second battery module.

9. The battery pack according to any one of claims 2-5, wherein, The first liquid cooling plate and the second liquid cooling plate are provided with avoidance portions, and the positions of the avoidance portions correspond to the components in the box body; and / or, the positions of the avoidance portions correspond to the components of the box cover.

10. The battery pack according to claim 9, wherein, A plurality of connecting columns are arranged in the box body, connecting holes are formed at positions corresponding to the connecting columns in the box cover, the connecting columns are inserted into the connecting holes, and the positions of the avoidance portions correspond to the connecting columns.

11. The battery pack according to claim 10, wherein, A plurality of cross beams are arranged in the box body, and the connecting columns are arranged on the cross beams.

12. The battery pack according to claim 11, wherein, The connecting column includes an internally threaded column, and a bolt passes through the connecting hole and is fixedly connected to the connecting column so as to fixedly connect the box cover and the box body.

13. The battery pack according to any one of claims 9-12, wherein, The first liquid cooling plate and the second liquid cooling plate include a liquid cooling portion and a connecting portion; Each of the liquid cooling portions respectively covers one of the first battery modules or the second battery modules, and the connecting portion is configured to connect two adjacent liquid cooling portions.

14. The battery pack according to claim 13, wherein, The avoidance portion is arranged on the connecting portion.

15. A vehicle, comprising the battery pack according to any one of claims 1-14.

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