Battery pack and electric device

Abstract

Disclosed are a battery pack and an electric device. In the battery pack, a first flow guide cavity is provided inside a side wall; a third explosion-proof valve is provided on a case; a first tray is provided inside the case, and a second flow guide cavity is provided inside the first tray; a first battery module is arranged on the first tray, and a first explosion-proof valve is provided at the end of first battery cells facing the first tray; a second tray is provided on the side of the first battery module facing away from the first tray, and a third flow guide cavity is provided inside the second tray; and a second battery module is arranged on the second tray, and a second explosion-proof valve is provided at the end of second battery cells facing the second tray.

Description

Battery packs and electrical equipment

[0001] This application claims priority to Chinese Patent Application No. 2024211681424, filed on May 27, 2024, entitled "Battery Pack and Electrical Equipment", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, specifically to a battery pack and electrical equipment. Background Technology

[0003] In a dual-layer battery pack, although exhaust channels are provided for the battery cells in the upper and lower layers to release thermal runaway gases, there is a risk that thermal runaway gases released from the upper battery cells may leak into the lower battery cells, and vice versa. This increases the risk of thermal runaway gas propagation within the battery pack and affects the safety of the battery pack. Invention Overview

[0004] In a first aspect, embodiments of this application provide a battery pack having intersecting first and third directions. The battery pack includes: a housing with an internal receiving cavity, the housing including two sidewalls disposed opposite each other along the first direction, at least one of the sidewalls having a first flow guiding cavity inside; a first tray disposed in the receiving cavity, the first tray having a second flow guiding cavity inside, the second flow guiding cavity communicating with the first flow guiding cavity; and a first battery pack including a plurality of first battery cells, the first battery pack being stacked with the first tray along the third direction, the end of each first battery cell facing the first tray having a first explosion-proof valve, the thermal runaway gas generated by the first battery cell being able to pass through the first explosion-proof valve. The gas is discharged into the second guide cavity; the second tray is disposed on the side of the first battery pack facing away from the first tray in the third direction, and the second tray has a third guide cavity inside, which is connected to the first guide cavity; the second battery pack is disposed on the side of the second tray facing away from the first battery pack in the third direction, and the second battery pack includes a plurality of second battery cells. Along the third direction, the end of the second battery cell facing the second tray is provided with a second explosion-proof valve, and the thermal runaway gas generated by the second battery cell can be discharged into the third guide cavity through the second explosion-proof valve; the third explosion-proof valve is disposed on the housing, and the air inlet of the third explosion-proof valve is connected to the first guide cavity.

[0005] Secondly, embodiments of this application also provide an electrical device, including the battery pack as described above. Attached Figure Description

[0006] Figure 1 is a schematic diagram of the battery pack provided in an embodiment of this application;

[0007] Figure 2 is an exploded view of Figure 1;

[0008] Figure 3 is a top view of the battery pack provided in the embodiment of this application after the cover plate has been removed;

[0009] Figure 4 is a schematic diagram of the structure of the battery pack provided in the embodiment of this application after removing the cover plate, BDU module and BMS module;

[0010] Figure 5 is a sectional view along line AA of Figure 4;

[0011] Figure 6 is an enlarged structural diagram of point B in Figure 5;

[0012] Figure 7 is a schematic diagram of the combined structure of the battery pack, including the housing, the first tray, the first battery pack, and the third explosion-proof valve, provided in an embodiment of this application.

[0013] Figure 8 is a schematic diagram of the combined structure of the battery pack housing, the first tray, and the third explosion-proof valve provided in the embodiment of this application.

[0014] Figure 9 is a cross-sectional view along the CC direction of Figure 8;

[0015] Figure 10 is an enlarged structural diagram of point D in Figure 9;

[0016] Figure 11 is a schematic diagram of the combined structure of the battery pack housing, the first tray, the second tray, and the third explosion-proof valve provided in the embodiment of this application.

[0017] Figure 12 is a sectional view along the EE direction of Figure 11;

[0018] Figure 13 is an enlarged structural diagram of point F in Figure 12;

[0019] Figure 14 is a schematic diagram of the side wall of the battery pack housing provided in the embodiment of this application;

[0020] Figure 15 is a schematic diagram of the end wall of the battery pack housing provided in the embodiment of this application;

[0021] Figure 16 is a schematic diagram of the first angle structure of the first tray in the battery pack provided in the embodiment of this application;

[0022] Figure 17 is a schematic diagram of the second angle structure of the first tray in the battery pack provided in the embodiment of this application;

[0023] Figure 18 is a schematic diagram of the first angle structure of the second tray in the battery pack provided in the embodiment of this application;

[0024] Figure 19 is a schematic diagram of the second angle structure of the second tray in the battery pack provided in the embodiment of this application;

[0025] Figure 20 is a schematic diagram of the liquid cooling system in the battery pack provided in an embodiment of this application;

[0026] Figure 21 is a schematic diagram of the structure of the first battery cell in the battery pack provided in the embodiment of this application;

[0027] Figure 22 is a schematic diagram of the structure of the second battery cell in the battery pack provided in the embodiment of this application. Implementation methods of this application

[0028] This application provides a secondary battery and a battery pack. To make the purpose, technical solution, and effects of this application clearer and more explicit, the following detailed description is provided with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining this application and are not intended to limit this application.

[0029] This embodiment provides an electrical device, including a battery pack 1, which serves as the power supply for the device. The electrical device may be, but is not limited to, mobile devices (e.g., mobile phones, laptops), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.

[0030] In some embodiments of this application, a battery pack 1 is provided. Referring to Figures 1-22, the battery pack 1 includes: a housing 10, a first tray 20, a first battery pack 30, a second tray 40, a second battery pack 50, and a third explosion-proof valve 60. The battery pack 1 has a first direction X, a second direction Y, and a third direction Z that intersect each other in pairs. Specifically, in the embodiments shown in Figures 1-13, the first direction X, the second direction Y, and the third direction Z are orthogonal to each other in pairs.

[0031] Referring to Figures 2-3 and 7-8, the housing 10 has an internal receiving cavity 101. Referring to Figures 1-2 and 7-9, the housing 10 includes two side walls 11 arranged opposite each other along a first direction X. Specifically, the two side walls 11 include a first side wall 11a and a second side wall 11b. At least one side wall 11 has a first flow guiding cavity 110 inside. The first flow guiding cavity 110 extends along a second direction Y. Specifically, in the embodiments shown in Figures 9-10 and 12-14, the first side wall 11a and the second side wall 11b are respectively provided with the first flow guiding cavity 110. Referring to Figures 1-2 and 5-8, the housing 10 further includes two end walls 12 arranged opposite each other along the second direction Y. Specifically, the two end walls 12 include a first end wall 12a and a second end wall 12b. Referring to Figure 2, the housing 10 also includes a bottom wall 14 and a top wall 15 arranged opposite each other along the third direction Z. Both the bottom wall 14 and the top wall 15 have through openings along the third direction Z. The first side wall 11a, the first end wall 12a, the second side wall 11b, and the second end wall 12b are connected end to end in sequence to form a shell structure with openings at both ends. The bottom wall 14 and the top wall 15 respectively cover the openings at both ends to form the housing 10. In the specific embodiments shown in Figures 1-13, the first direction X is parallel to the width direction of the housing 10, the second direction Y is parallel to the length direction of the housing 10, and the third direction Z is parallel to the height direction of the housing 10.

[0032] Referring to Figures 2-3, 5-6, 8-13 and 16-17, the first tray 20 is disposed in the receiving cavity 101. Referring to Figures 6, 10, 13 and 17, the first tray 20 is provided with a second flow guiding cavity 201, which is connected to the first flow guiding cavity 110.

[0033] Referring to Figures 2-7, the first battery pack 30 is disposed in the receiving cavity 101. The first battery pack 30 and the first tray 20 are stacked along the third direction Z. The first battery pack 30 includes a plurality of first battery cells 31. Referring to Figures 6 and 21, the first battery cell 31 has a first explosion-proof valve 311 at one end facing the first tray 20 in the third direction Z. The thermal runaway gas generated by the first battery cell 31 can be discharged into the second guide cavity 201 of the first tray 20 through the first explosion-proof valve 311.

[0034] Referring to Figures 2-6 and 11-13, the second tray 40 is disposed on the side of the first battery pack 30 facing away from the first tray 20 in the third direction Z. In other words, the second tray 40 and the first battery pack 30 are spaced apart along the third direction Z. Referring to Figures 6 and 13, the second tray 40 is provided with a third flow guiding cavity 401 inside, and the third flow guiding cavity 401 is connected to the first flow guiding cavity 110.

[0035] Referring to Figures 2-6, the second battery pack 50 is disposed on the side of the second tray 40 facing away from the first tray 20 in the third direction Z. The second battery pack 50 includes a plurality of second battery cells 51. Referring to Figures 6 and 22, the end of the second battery cell 51 facing the second tray 40 in the third direction Z is provided with a second explosion-proof valve 511. The thermal runaway gas generated by the second battery cell 51 can be discharged into the third guide cavity 401 of the second tray 40 through the second explosion-proof valve 511.

[0036] The third explosion-proof valve 60 is installed on the housing 10. The air inlet of the third explosion-proof valve 60 is connected to the first guide cavity 110. In some implementations, the third explosion-proof valve 60 is inserted into the first side wall 11a or the second side wall 11b. In some implementations, one third explosion-proof valve 60 is installed on the first side wall 11a and the second side wall 11b respectively. The specific choice can be made according to the actual use requirements.

[0037] In a dual-layer battery pack, although exhaust channels are provided for the battery cells in the upper and lower layers to release thermal runaway gases, there is a risk that the thermal runaway gases released from the upper battery cells may leak into the lower battery cells, and similarly, there is a risk that the thermal runaway gases released from the lower battery cells may leak into the upper battery cells. The leaked thermal runaway gases can spread to battery cells that have not yet experienced thermal runaway and cause them to experience thermal runaway, thereby increasing the risk of thermal runaway spreading within the battery pack and affecting the safety of the battery pack.

[0038] The battery pack 1 provided in this application embodiment has a first flow guide cavity 110 inside the side wall 11, a third explosion-proof valve 60 is set on the housing 10, the air inlet of the third explosion-proof valve 60 is connected to the first flow guide cavity 110, a first tray 20 is set inside the housing cavity 101 of the housing 10, a second flow guide cavity 201 is set inside the first tray 20 and the second flow guide cavity 201 is connected to the first flow guide cavity 110, a first battery pack 30 is set on the first tray 20, and a first explosion-proof valve 311 is set at the end of the first battery cell 31 in the first battery pack 30 facing the first tray 20 in the third direction Z. The thermal runaway gas generated by the first battery cell 31 can be discharged to the second guide cavity 201 through the first explosion-proof valve 311, and then discharged into the first guide cavity 110 through the second guide cavity 201. A second tray 40 is provided on the side of the first battery pack 30 away from the first tray 20. A third guide cavity 401 is provided inside the second tray 40 and is connected to the first guide cavity 110. The second battery pack 50 is placed on the second tray 40. A second explosion-proof valve 511 is provided at the end of the second battery cell 51 in the second battery pack 50 facing the second tray 40 in the third direction Z. The thermal runaway gas generated by the second battery cell 51 can be discharged into the third guide cavity 401, and then discharged into the first guide cavity 110 through the third guide cavity 401. The gas is placed in the first guide cavity 110, so that the thermal runaway gas generated by the first battery cell 31 and the thermal runaway gas generated by the second battery cell 51 are both discharged into the first guide cavity 110. The gas is then discharged to the outside of the battery pack 1 in a timely and smooth manner through the third explosion-proof valve 60 connected to the first guide cavity 110. This prevents the thermal runaway gas generated by the first battery cell 31 from leaking into the second battery pack 50 during the discharge process, and also prevents the thermal runaway gas generated by the second battery cell 51 from leaking into the first battery pack 30 during the discharge process. This effectively reduces the risk of thermal runaway gas spreading to other battery cells that have not experienced thermal runaway due to leakage, and ensures the safety of the battery pack 1.

[0039] In some embodiments, referring to Figures 2-7, 21, and 22, the first battery cell 31 and the second battery cell 51 are cylindrical batteries. In other implementations, the first battery cell 31 and the second battery cell 51 can be prismatic batteries or other irregularly shaped batteries, as long as the first explosion-proof valve 311 is disposed at the end of the first battery cell 31 facing the first tray 20, and the second explosion-proof valve 511 is disposed at the end of the second battery cell 51 facing the second tray 40.

[0040] In some embodiments, referring to Figures 8-9 and 16, the first tray 20 has a support surface 21 facing the first battery pack 30 in the third direction Z. The first battery pack 30 is disposed on the support surface 21. Referring to Figures 6, 8-12 and 16, a first through hole 22 is provided on the support surface 21 in the third direction Z. The first through hole 22 communicates with the second guide cavity 201. The number of first through holes 22 corresponds one-to-one with the number of first battery cells 31. The first explosion-proof valve 311 on the first battery cell 31 is disposed opposite to the first through hole 22 in the third direction Z. The thermal runaway gas generated by the first battery cell 31 is discharged into the second guide cavity 201 through the first explosion-proof valve 311 and the first through hole 22.

[0041] In some embodiments, referring to FIG6, the second tray 40 has a second through hole 41 on the side facing the second battery pack 50 in the third direction Z. The second through hole 41 penetrates the side of the second tray 40 facing the second battery pack 50 in the third direction Z. The second through hole 41 communicates with the third guide cavity 401. The number of second through holes 41 corresponds one-to-one with the number of second battery cells 51. The second explosion-proof valve 511 on the second battery cell 51 is disposed opposite to the second through hole 41 in the third direction Z. The thermal runaway gas generated by the second battery cell 51 is discharged into the third guide cavity 401 through the second explosion-proof valve 511 and the second through hole 41.

[0042] In some embodiments, referring to FIG15, at least one end wall 12 of the housing 10 is provided with a fourth flow guide cavity 120. Specifically, in the embodiments shown in FIG5 and FIG6, the first end wall 12a and the second end wall 12b are both provided with a fourth flow guide cavity 120. The fourth flow guide cavity 120 extends along the first direction X and is connected to the first flow guide cavity 110. Referring to FIG1-FIG and FIG5-FIG6, a third explosion-proof valve 60 is disposed on the end wall 12. Specifically, in the embodiments shown in FIG5 and FIG6, the third explosion-proof valve 60 is disposed on the first end wall 12a, and the air inlet end of the third explosion-proof valve 60 is connected to the fourth flow guide cavity 120. Since the first sidewall 11a, the first endwall 12a, the second sidewall 11b, and the second endwall 12b are sequentially connected end to end, the first guide cavity 110 in the sidewall 11 is connected to the fourth guide cavity 120 in the endwall 12. This allows the thermal runaway gas generated by the first battery cell 31 and the thermal runaway gas generated by the second battery cell 51 to enter the fourth guide cavity 120 through the first guide cavity 110, and then be discharged to the outside of the battery pack 1 through the third explosion-proof valve 60. The fourth guide cavity 120 extends the discharge path of the thermal runaway gas entering the first guide cavity 110, thereby reducing the temperature and / or pressure of the thermal runaway gas and minimizing damage to the components of the electrical equipment caused by excessively high temperature and / or pressure of the thermal runaway gas discharged to the outside of the battery pack 1.

[0043] In some embodiments, referring to Figures 9, 10 and 14, the housing 10 further includes at least one first baffle 131, which is disposed in the first flow guide cavity 110 and internally connected to the side wall 11 to divide the first flow guide cavity 110 into at least two partitions 1100 spaced apart along the third direction Z. The second flow guide cavity 201 in the first tray 20 communicates with one of the at least two partitions 1100, and the third flow guide cavity 401 in the second tray 40 communicates with the other of the at least two partitions 1100. The first baffle 131 divides the first flow guide cavity 110 into at least two spaced-apart cavities 1100. This prevents thermal runaway gas generated by the first battery cell 31 from leaking into the second battery pack 50 through the third flow guide cavity 401 after entering the first flow guide cavity 110, and similarly prevents it from leaking into the first battery pack 30 through the second flow guide cavity 201. This further reduces the risk of thermal runaway gas spreading within the battery pack 1 and improves the safety of the battery pack 1. "Internal connection" means that the first baffle 131 is located within the first flow guide cavity 110 on the inner side of the side wall 11 and is connected to the side wall 11.

[0044] In the specific embodiments shown in Figures 10 and 13, there are three first baffles 131, spaced apart along the third direction Z, dividing the first guide cavity 110 into a first partition 1101, a second partition 1102, a third partition 1103, and a fourth partition 1104, also spaced apart along the third direction Z. The first partition 1101 communicates with the second guide cavity 201, and the third guide cavity 1101 communicates with the fourth partition 1104. A third explosion-proof valve 60 is disposed on the side wall 11, and its inlet is connected to both the first partition 1101 and the fourth partition 1104.

[0045] In some embodiments, referring to Figures 6 and 15, the housing 10 further includes at least one second baffle 132, which is disposed in the fourth flow guide cavity 120 and internally connected to the end wall 12 to divide the fourth flow guide cavity 120 into at least two cavities 1200 spaced apart along the third direction Z. The partition 1100 connected to the second flow guide cavity 201 is connected to one of the at least two cavities 1200, and the partition 1100 connected to the third flow guide cavity 401 is connected to the other of the at least two cavities 1200. The second baffle 132 divides the fourth guide cavity 120 into at least two spaced cavities 1200. This prevents the thermal runaway gas generated by the first battery cell 31 from leaking into the second battery pack 50 through the first guide cavity 110 after entering the fourth guide cavity 120 via the first guide cavity 110, due to the obstruction of the second baffle 132. Similarly, the thermal runaway gas generated by the second battery cell 51 is also prevented from leaking into the first battery pack 30 through the first guide cavity 110 after entering the fourth guide cavity 120 via the first guide cavity 110, due to the obstruction of the second baffle 132. This further reduces the risk of thermal runaway gas spreading inside the battery pack 1 and improves the safety of the battery pack 1.

[0046] In the embodiment shown in Figure 6, there are two second baffles 132, spaced apart along the third direction Z, dividing the fourth guide cavity 120 into a first cavity 1201, a second cavity 1202, and a third cavity 1203 spaced apart along the third direction Z. A partition 1100 connected to the second guide cavity 201 is connected to the first cavity 1201. Specifically, the first partition 1101 is connected to the first cavity 1201, and the partition 1100 connected to the third guide cavity 401 is connected to the third cavity 1203. Specifically, the fourth partition 1104 is connected to the third cavity 1203. In the embodiment shown in Figure 6, the third explosion-proof valve 60 is disposed on the first end wall 12a. The air inlet of the third explosion-proof valve 60 is connected to the second cavity 1202, and the air inlet of the third explosion-proof valve 60 is also connected to both the first cavity 1201 and the third cavity 1203.

[0047] In some embodiments, referring to Figures 7-14, a first protrusion 112 protrudes from the sidewall 11 facing the first tray 20 along the first direction X. Referring to Figures 11-13, the second tray 40 and the first protrusion 112 are stacked along the third direction Z, with the first protrusion 112 supporting the second tray 40. Specifically, in the embodiments shown in Figures 7-14, the first sidewall 11a and the second sidewall 11b respectively protrude from the side facing the first tray 20 in the first direction X, with the two first protrusions 112 cooperating to form support for both ends of the second tray 40 in the first direction X. By using the first protrusion 112 to design the second tray 40 inside the housing 10, no additional support structure is needed inside the housing 10, thereby improving the space utilization inside the housing 10 and increasing the energy density of the battery pack 1. To ensure the assembly stability of the second tray 40 and the second battery pack 50 within the housing 10, after the second tray 40 and the second battery pack 50 are assembled, potting compound can be injected into the receiving cavity 101 to ensure assembly stability.

[0048] In some embodiments, referring to Figures 7-10 and 13-14, along the third direction Z, the side of the first protrusion 112 facing the second tray 40 has a second guide hole 113 communicating with the first guide cavity 110. Referring to Figures 13 and 19, the side of the second tray 40 facing the first tray 20 has a second exhaust hole 42 communicating with the third guide cavity 401. Referring to Figure 13, the second exhaust hole 42 and the second guide hole 113 communicate to connect the third guide cavity 401 and the first guide cavity 110. The arrangement of the second exhaust hole 42 and the second guide hole 113 ensures that after the thermal runaway gas generated by the second battery cell 51 enters the third guide cavity 401, it can only be discharged into the first guide cavity 110 through the second exhaust holes 42 opened at both ends of the second tray 40 in the first direction X, thereby preventing the thermal runaway gas entering the third guide cavity 401 from being discharged through other parts of the second tray 40, avoiding leakage of thermal runaway gas, and reducing the risk of thermal propagation.

[0049] In some embodiments, referring to Figures 9-10, 13, and 14, a first guide hole 111 communicating with the first guide cavity 110 is formed on the side of the sidewall 11 facing the first tray 20 along the first direction X. Referring to Figures 10 and 17, a first exhaust hole 23 communicating with the second guide cavity 201 is formed at one end of the first tray 20 facing the sidewall 11. Referring to Figure 10, along the first direction X, the first tray 20 abuts against the sidewall 11, and the first guide hole 111 communicates with the first exhaust hole 23 to connect the second guide cavity 201 and the first guide cavity 110. The design of the first exhaust port 23 and the first guide port 111 ensures that the thermal runaway gas generated by the first battery cell 31 can only be discharged into the first guide port 110 through the first exhaust port 23 at both ends of the first tray 20 in the first direction X after entering the second guide cavity 201. This prevents the thermal runaway gas in the second guide cavity 201 from being discharged through other parts of the first tray 20, avoids leakage of thermal runaway gas, and reduces the risk of thermal spread.

[0050] In some embodiments, referring to Figures 7-14, a second protrusion 114 is provided on the side of the sidewall 11 facing the first tray 20 along the first direction X. Referring to Figure 14, the second protrusion 114 includes a mounting surface 1141 facing the first tray 20, and the mounting surface 1141 is inclined to form a slope. Referring to Figures 16 and 17, the first tray 20 includes an end face 202 facing the sidewall 11, that is, the first tray 20 includes two end faces 202 arranged opposite to each other along the first direction X, and the end faces 202 are inclined to form a slope. Referring to Figure 17, a first vent 23 is opened on the end face 202. Along the first direction X, the first tray 20 abuts against the sidewall 11, and the end face 202 abuts against the mounting surface 1141 of the second protrusion 114. The sloping design of the mounting surface 1141, in conjunction with the inclined design of the end face 202, enhances the connection stability between the first tray 20 and the side wall 11, preventing the first tray 20 from separating from the side wall 11 when the battery pack 1 shakes. This also prevents thermal runaway gas entering the first guide cavity 110 through the second guide cavity 201 from leaking at the connection between the first exhaust port 23 and the first guide hole 111, thus reducing the risk of heat propagation.

[0051] In some embodiments, referring to FIG2, the battery pack 1 further includes a first partition 24, which is disposed between the first tray 20 and the first battery pack 30. The first partition 24 is configured to be ruptured by the thermal runaway gas generated by the first battery cell 31 under a preset pressure, so that the thermal runaway gas is discharged into the second guide cavity 201 through the first explosion-proof valve 311 and the first through hole 22. The first partition 24 can form a barrier between the second guide cavity 201 and the first battery cell 31 that has not experienced thermal runaway. That is, the first partition 24 corresponding to the first battery cell 31 that has not experienced thermal runaway is not ruptured, thus avoiding the thermal runaway gas entering the second guide cavity 201 from having a thermal impact on the first battery cell 31 that has not experienced thermal runaway, thereby preventing the spread of thermal runaway and ensuring the safety of the battery pack 1.

[0052] In some embodiments, the first partition 24 may be a mica board or a mica sheet made of multiple layers of mica paper.

[0053] In some embodiments, referring to FIG2, the battery pack 1 further includes a second partition 43, which is disposed between the second tray 40 and the second battery pack 50. The second partition 43 is configured to be ruptured by the thermal runaway gas generated by the second battery cell 51 under a preset pressure, thereby allowing the thermal runaway gas to be discharged into the third flow channel 401 through the second explosion-proof valve 511 and the second through hole 41. The arrangement of the second partition 43 can form a barrier between the third flow channel 401 and the second battery cell 51 that has not experienced thermal runaway. That is, the second partition 43 corresponding to the second battery cell 51 that has not experienced thermal runaway is not ruptured, thus preventing the thermal runaway gas entering the third flow channel 401 from having a thermal impact on the second battery cell 51 that has not experienced thermal runaway, thereby preventing the spread of thermal runaway and ensuring the safety of the battery pack 1.

[0054] In some embodiments, the second partition 43 may be a mica board or a mica sheet made of multiple layers of mica paper.

[0055] In some embodiments, referring to Figures 2-4, 6, and 20, the battery pack 1 further includes a plurality of first liquid cooling plates 71, a plurality of second liquid cooling plates 72, a shunt pipe 73, a manifold 74, a first liquid inlet pipe 711, a first liquid outlet pipe 712, a second liquid inlet pipe 721, a second liquid outlet pipe 722, a liquid inlet connector 75, and a liquid outlet connector 76. Referring to Figure 6, the plurality of first liquid cooling plates 71 are spaced apart along a third direction Z between the first tray 20 and the second tray 40, and the first battery cell 31 is disposed between two adjacent first liquid cooling plates 71. Specifically, the first liquid cooling plates 71 are spaced apart along a third direction Z. Extending in the X direction, a plurality of first liquid cooling plates 71 are spaced apart along the second direction Y, and at least one first battery cell 31 is disposed between two adjacent first liquid cooling plates 71. A plurality of second liquid cooling plates 72 are spaced apart along the third direction Z on the side of the second tray 40 facing away from the first tray 20 in the third direction X. A second battery cell 51 is disposed between two adjacent second liquid cooling plates 72. Specifically, the second liquid cooling plates 72 extend in the first direction X, a plurality of second liquid cooling plates 72 are spaced apart along the second direction Y, and at least one second battery cell 51 is disposed between two adjacent second liquid cooling plates 72. Referring to Figure 20, one end of a plurality of first liquid cooling plates 71 along the first direction X is connected through a first liquid inlet pipe 711, and the other end is connected through a first liquid outlet pipe 712. One end of a plurality of second liquid cooling plates 72 along the first direction X is connected through a second liquid inlet pipe 721, and the other end is connected through a second liquid outlet pipe 722. Referring to Figures 3 and 4, a liquid inlet connector 75 and a liquid outlet connector 76 are respectively disposed on the end wall 12. Specifically, in the embodiments shown in Figures 3 and 4, a liquid inlet connector 75 and a liquid outlet connector 76 are respectively disposed on the second end wall 12b. Referring to Figure 20, the first liquid inlet pipe 711 and the second liquid inlet pipe 721 are connected to the liquid inlet connector 75 through a diverter pipe 73, and the first liquid outlet pipe 712 and the second liquid outlet pipe 722 are connected to the liquid outlet connector 76 through a manifold pipe 74. The distribution pipe 73 allows the inlet connector 75 to simultaneously supply heat-conducting fluid to the first liquid cooling plate 71 and the second liquid cooling plate 72. The manifold 74 allows the heat-conducting fluid in the first liquid cooling plate 71 and the second liquid cooling plate 72 to be discharged through the outlet connector 76, thereby realizing the circulation of heat-conducting fluid in the first liquid cooling plate 71 and the second liquid cooling plate 72, improving the flow efficiency of heat-conducting fluid, improving heat transfer efficiency, and achieving a balanced cooling effect between the first battery cell 31 and the second battery cell 51. It can also improve the space utilization inside the housing 10, thereby increasing the energy density of the battery pack 1.

[0056] In some embodiments, both the first liquid cooling plate 71 and the second liquid cooling plate 72 are made of aluminum alloy, which has good strength and rigidity, and the surface is coated with an insulating layer to avoid short circuits between the cells.

[0057] In some embodiments, the first liquid cooling plate 71 and the second liquid cooling plate 72 may also be made of non-metallic materials, such as PA12, PPO, PPS and other plastic materials, which have good strength and rigidity. The plastic materials themselves have good insulation properties, so there is no need to spray an additional insulation layer, thereby reducing the cost of the first liquid cooling plate 71 and the second liquid cooling plate 72.

[0058] In some embodiments, referring to FIG3, along the second direction Y, the length of the first tray 20 is L1mm and the length of the second tray 40 is L2mm, satisfying L2<L1.

[0059] In some embodiments, referring to FIG3, the distance between the two end walls 12 is L3mm. Specifically, the distance between the sides of the first end wall 12a and the second end wall 12b that are opposite to each other in the second direction Y is L3mm, satisfying L1<L3.

[0060] In some embodiments, L2 < L3.

[0061] In some embodiments, L1+L2>L3.

[0062] When L1, L2, and L3 satisfy any of the above relationships, the number of second battery cells 51 in the second battery pack 50 arranged along the second direction Y can be less than the number of first battery cells 31 in the first battery pack 30 arranged along the second direction Y. This makes reasonable use of the length space of the battery pack 1 in the second direction Y. While ensuring that the first battery cells 31 and the second battery cells 51 are arranged in a concentrated manner, space can be provided in the receiving cavity 101 located above the first battery pack 30 for the battery management module and supporting devices such as the shunt pipe 73 and the busbar 74, thereby improving space utilization. Moreover, when L1, L2, and L3 satisfy any of the above relationships, the battery pack 1 can meet the voltage requirements of the electrical equipment through reasonable spatial layout, saving space, reducing assembly difficulty, eliminating the need for auxiliary components such as series and parallel cables, and making the overall structure more compact.

[0063] In some embodiments, referring to Figures 2 and 3, the battery pack 1 further includes a BMS module 81 and a BDU module 82. BMS stands for Battery Management System, and BDU stands for Battery Disconnect Unit. Along the second direction Y, a first accommodating cavity is defined between the first battery pack 30 and the end wall 12, and the BMS module 81 is disposed in the first accommodating cavity. A second accommodating cavity is defined between the second battery pack 50 and the end wall 12, and the BDU module 82 is disposed in the second accommodating cavity. The BMS module 81 and the BDU module 82 are spaced apart along the third direction Z. Referring to Figure 2, the BMS module 81 includes a plurality of control boards 811 spaced apart along the first direction X. Referring to Figure 3, the BDU module 82 includes a plurality of connectors 821 spaced apart along the first direction X. Specifically, the plurality of connectors 821 include signal connectors, high-voltage connectors, and fast-charging connectors.

[0064] In some embodiments, referring to FIG2, the battery pack 1 further includes a bottom plate 91 and a first cover plate 92. The bottom plate 91 covers the bottom wall 14 of the housing 10, and the first cover plate 92 covers the top wall 15 of the housing 10. Referring to FIG2, the first cover plate 92 is provided with a third protrusion 921. Specifically, the first cover plate 92 protrudes on the side facing away from the bottom plate 91 in the third direction Z to form the third protrusion 921 to accommodate the second battery pack 50. The BDU module 82 is disposed on the side of the first cover plate 92 facing away from the bottom plate 91 in the third direction Z, and is spaced apart from the third protrusion 921 along the second direction Y. The second cover plate 93 covers the BDU module 82.

[0065] In some embodiments, after the first tray 20, the first battery pack 30, the second tray 40, the second battery pack 50, and other parts inside the battery pack 1 are assembled with the housing 10, the first tray 20, the first battery pack 30, the second tray 40, the second battery pack 50, and other parts are cured into one piece by injecting glue (e.g., potting compound) into the housing 10, thereby achieving the effect of fixing the components inside the housing 10. The potting compound can enter the receiving cavity 101 of the housing 10 through the gaps and gaps between the components, so that the first cover plate 92, the bottom plate 91 and all the components inside the housing 10 are bonded together. After the potting compound is cured, the battery pack 1 forms a whole and has good mechanical properties.

[0066] The technical solutions provided by the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A battery pack having intersecting first and third directions, wherein, The battery pack includes: The box has an internal cavity, and the box includes two side walls arranged opposite each other along the first direction, and at least one of the side walls has a first flow guide cavity inside. A first tray is disposed in the receiving cavity, and a second flow guiding cavity is provided inside the first tray, the second flow guiding cavity being in communication with the first flow guiding cavity; The first battery pack includes multiple first battery cells. Along the third direction, the first battery pack is stacked with the first tray. The first battery cell is provided with a first explosion-proof valve at one end facing the first tray. The thermal runaway gas generated by the first battery cell can be discharged to the second guide cavity through the first explosion-proof valve. The second tray is disposed on the side of the first battery pack facing away from the first tray in the third direction. The second tray has a third flow guiding cavity inside, and the third flow guiding cavity is connected to the first flow guiding cavity. The second battery pack is disposed on the side of the second tray facing away from the first battery pack in the third direction. The second battery pack includes a plurality of second battery cells. Along the third direction, a second explosion-proof valve is provided at one end of the second battery cell facing the second tray. The thermal runaway gas generated by the second battery cell can be discharged to the third guide cavity through the second explosion-proof valve. A third explosion-proof valve is installed on the housing, and the air inlet of the third explosion-proof valve is connected to the first guide cavity.

2. The battery pack as claimed in claim 1, wherein, The battery pack also has a second direction, wherein the first direction, the second direction, and the third direction intersect each other; The housing also includes two end walls arranged opposite each other along the second direction, one of the side walls and one of the end walls are connected, and at least one of the end walls is provided with a fourth flow guiding cavity inside, and the fourth flow guiding cavity is in communication with the first flow guiding cavity; The third explosion-proof valve is disposed on the end wall, and the air inlet of the third explosion-proof valve is connected to the fourth flow guide cavity.

3. The battery pack as described in claim 2, wherein, The housing further includes at least one first baffle, which is disposed in the first flow guide cavity and internally connected to the side wall to divide the first flow guide cavity into at least two partitions spaced apart along the third direction. The second flow guide cavity communicates with one of the at least two partitions, and the third flow guide cavity communicates with the other of the at least two partitions.

4. The battery pack as claimed in claim 2, wherein, The housing further includes at least one second baffle, which is disposed in the fourth flow guide cavity and internally connected to the end wall to divide the fourth flow guide cavity into at least two cavities spaced apart along the third direction. The partition cavity connected to the second flow guide cavity is connected to one of the at least two cavities, and the partition cavity connected to the third flow guide cavity is connected to the other of the at least two cavities.

5. The battery pack as described in claim 2, wherein, The housing further includes at least one first baffle, which is disposed in the first flow guide cavity and internally connected to the side wall to divide the first flow guide cavity into at least two partitions spaced apart along the third direction. The second flow guide cavity communicates with one of the at least two partitions, and the third flow guide cavity communicates with the other of the at least two partitions. The housing further includes at least one second baffle, which is disposed in the fourth flow guide cavity and internally connected to the end wall to divide the fourth flow guide cavity into at least two cavities spaced apart along the third direction. The partition cavity connected to the second flow guide cavity is connected to one of the at least two cavities, and the partition cavity connected to the third flow guide cavity is connected to the other of the at least two cavities.

6. The battery pack as claimed in claim 1, wherein, Along the first direction, a first protrusion is provided on the side of the sidewall facing the first tray; The second tray and the first protrusion are stacked along the third direction, and the first protrusion is used to support the second tray; Along the third direction, the first protrusion has a second flow hole on the side facing the second tray that communicates with the first flow cavity, and the second tray has a second exhaust hole on the side facing the first tray that communicates with the third flow cavity. The second exhaust hole communicates with the second flow hole to connect the third flow cavity and the first flow cavity.

7. The battery pack as claimed in claim 1, wherein, Along the first direction, the sidewall facing the first tray has a first flow guide hole communicating with the first flow guide cavity, and the first tray has a first exhaust hole communicating with the second flow guide cavity at one end facing the sidewall; Along the first direction, the first tray abuts against the side wall, and the first vent hole communicates with the first guide hole to connect the second guide cavity and the first guide cavity.

8. The battery pack as claimed in claim 7, wherein, Along the first direction, a second protrusion is provided on the side of the sidewall facing the first tray. The second protrusion includes a mounting surface facing the first tray. The mounting surface is inclined to form a slope. The first tray includes an end face facing the sidewall. The end face is inclined to form a slope. The first guide hole is formed on the mounting surface, and the first exhaust hole is formed on the end face; Along the first direction, the end face abuts against the mounting surface.

9. The battery pack as claimed in claim 1, wherein, The battery pack also includes a first separator, which is disposed between the first tray and the first battery pack. The first separator is configured to be ruptured by thermal runaway gas generated by the first battery cell under a preset pressure.

10. The battery pack of claim 1, wherein, The battery pack also includes a second separator disposed between the second tray and the second battery pack. The second separator is configured to be ruptured by thermal runaway gas generated by the second battery cell under a preset pressure.

11. The battery pack of claim 1, wherein, The battery pack also includes a first separator, which is disposed between the first tray and the first battery pack. The first separator is configured to be ruptured by thermal runaway gas generated by the first battery cell under a preset pressure. The battery pack also includes a second separator disposed between the second tray and the second battery pack. The second separator is configured to be ruptured by thermal runaway gas generated by the second battery cell under a preset pressure.

12. The battery pack as claimed in claim 2, wherein, The battery pack also includes multiple first liquid cooling plates, multiple second liquid cooling plates, a shunt pipe, a manifold, a first liquid inlet pipe, a first liquid outlet pipe, a second liquid inlet pipe, a second liquid outlet pipe, a liquid inlet connector, and a liquid outlet connector; Multiple first liquid cooling plates are spaced apart between the first tray and the second tray, and the first battery cell is disposed between two adjacent first liquid cooling plates; Multiple second liquid cooling plates are spaced apart on the side of the second tray facing away from the first tray in the third direction, and the second battery cell is disposed between two adjacent second liquid cooling plates; One end of one of the multiple first liquid cooling plates is connected through the first liquid inlet pipe, and the other end is connected through the first liquid outlet pipe; One end of one of the multiple second liquid cooling plates is connected through the second liquid inlet pipe along the first direction, and the other end is connected through the second liquid outlet pipe; The inlet connector and the outlet connector are respectively disposed on the end wall. The first inlet pipe and the second inlet pipe are connected to the inlet connector through the diverter pipe. The first outlet pipe and the second outlet pipe are connected to the outlet connector through the manifold pipe.

13. The battery pack as claimed in claim 2, wherein, Along the second direction, the length of the first tray is L1mm, the length of the second tray is L2mm, and the distance between the two end walls is L3mm, satisfying at least one of the following conditions: 1) L2 < L1; 2) L1 < L3; 3) L2 < L3; 4) L1+L2>L3.

14. The battery pack as claimed in claim 2, wherein, The battery pack 1 also includes a BMS module and a BDU module; Along the second direction, a first receiving cavity is defined between the first battery pack and the end wall, and the BMS module is disposed in the first receiving cavity. A second receiving cavity is defined between the second battery pack and the end wall, and the BDU module is disposed in the second receiving cavity. The BMS module and the BDU module are spaced apart along the third direction.

15. An electrical appliance, wherein, Includes the battery pack as described in any one of claims 1 to 14.

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