Battery pack and electric apparatus

Abstract

The present application provides a battery pack and an electric apparatus. The battery pack comprises a lower housing, a battery unit composed of a plurality of battery cells arranged side by side, a cooling structure and an exhaust structure. The cooling structure comprises a bottom liquid cooling plate provided on the lower housing and a plurality of side liquid cooling plates provided on the bottom liquid cooling plate side by side, a mounting space for a single battery cell is defined between the bottom liquid cooling plate and two adjacent side liquid cooling plates, and an explosion-proof valve of each battery cell is provided towards the bottom liquid cooling plate. The exhaust structure comprises a bottom exhaust cavity formed between the bottom liquid cooling plate and the lower housing, and side exhaust cavities formed in side portions of the lower housing and used for communicating the bottom exhaust cavity and the atmosphere, exhaust holes having one-to-one correspondence to the explosion-proof valves are formed in the bottom liquid cooling plate, and the exhaust holes are communicated with the bottom exhaust cavity. In the battery pack of the present application, the internal temperatures of the battery cells can be quickly raised or lowered, ensuring a balanced temperature across all the battery cells, and avoiding the accumulation of high-temperature fumes in the battery pack, thereby improving the safety of the battery pack.

Description

Battery packs and electrical devices

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application with application number CN202322661868.3 and title “Battery Pack and Electrical Device” filed with the Patent Office of China on September 28, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of new energy battery pack structure and thermal safety technology, and in particular to a battery pack and an electrical device having the battery pack. Background Art

[0004] Because pouch cells are encapsulated with aluminum-plastic film, they are weaker than prismatic cells and are more likely to spread to other cells if thermal runaway occurs. Existing power battery systems often use liquid cooling plates to cool the cells to reduce the risk of overheating or underheating of individual cells during use.

[0005] However, existing technologies employ single-plate liquid cooling plates installed below or above the battery cells, resulting in a simple structure and poor cooling and heating performance. In particular, the temperature in the center of the battery cell cannot be quickly adjusted, resulting in a large temperature difference between the center and the outside of the battery cell. This makes it impossible to meet the heating and cooling requirements of extreme operating conditions, as well as the cooling requirements required in thermal runaway situations. Furthermore, because most existing battery cells have explosion-proof valves installed on the side, the smoke mixture released by the explosion-proof valves can only be discharged through a single path. Failure to discharge the smoke mixture in a timely manner can easily lead to a sharp increase in pressure and temperature within the battery pack, which can easily cause the battery pack to explode, compromising passenger safety.

[0006] Application Contents

[0007] In view of this, the present application aims to propose a battery pack that can quickly heat or cool the internal temperature of the battery cell to balance the temperature of the entire battery cell, and can provide a venting path for the vent valve to avoid the accumulation of high-temperature smoke inside the battery pack, thereby improving the safety of the battery pack.

[0008] In a first aspect, the present application provides a battery pack, comprising a lower housing, a battery unit consisting of a plurality of battery cells arranged side by side, a cooling structure, and an exhaust structure;

[0009] The cooling structure includes a bottom liquid cooling plate provided on the lower shell, and a plurality of side liquid cooling plates provided side by side on the bottom liquid cooling plate, wherein an installation space for a single battery cell is defined between the bottom liquid cooling plate and two adjacent side liquid cooling plates, and an explosion-proof valve of each battery cell is provided toward the bottom liquid cooling plate;

[0010] The exhaust structure includes a bottom exhaust cavity formed between the bottom liquid cooling plate and the bottom of the lower shell, and a side exhaust cavity formed on the side of the lower shell and used to connect the bottom exhaust cavity and the atmosphere. The bottom liquid cooling plate is provided with exhaust holes corresponding to the explosion-proof valves, and the exhaust holes are connected to the bottom exhaust cavity.

[0011] Beneficial Effects: By disposing a bottom liquid cooling plate on the lower housing and side liquid cooling plates arranged side by side above the bottom liquid cooling plate, with the side liquid cooling plates positioned between two adjacent battery cells, the heat transfer area is increased, enabling rapid heating or cooling of the internal temperature of the battery cells, thereby achieving temperature balance across the entire battery cell. Furthermore, by disposing a bottom exhaust cavity between the bottom liquid cooling plate and the lower housing, as well as a side exhaust cavity connecting the bottom exhaust cavity to the atmosphere, high-temperature flue gas is discharged from the bottom exhaust cavity into the side exhaust cavity and then into the atmosphere, preventing high-temperature flue gas from accumulating inside the battery pack and improving battery pack safety.

[0012] In an optional embodiment, the bottom liquid cooling plate is provided with a first liquid inlet channel and a first liquid outlet channel that are oppositely arranged, and a plurality of first communication channels that are provided between the first liquid inlet channel and the first liquid outlet channel for connecting the two;

[0013] The first liquid inlet channel is used to input the cooling medium into each of the first communication channels;

[0014] The first liquid outlet channel is used to output the cooling medium in each of the first communication channels to the outside.

[0015] Beneficial effect: The first liquid inlet channel and the first liquid outlet channel are arranged in communication with each other on the bottom liquid cooling plate, so that the cooling medium can circulate in the bottom liquid cooling plate, thereby improving the cooling effect of the bottom liquid cooling plate.

[0016] In an optional embodiment, the side liquid cooling plate is provided with a plurality of second communication channels spaced apart along its length direction;

[0017] The bottom end of each second communication channel is communicated with one of the adjacent first communication channels.

[0018] Beneficial Effect: Providing a second connecting channel on the side liquid cooling plate facilitates the flow of cooling medium in a directional manner along the length of the side liquid cooling plate, improving the cooling effect. The second connecting channel connects to the first connecting channel, allowing the cooling medium to flow from the bottom liquid cooling plate to the side liquid cooling plate, ensuring temperature balance between the bottom and sides of the battery cell and improving the safety of the battery cell.

[0019] In an optional embodiment, a plurality of the first communicating channels are provided between two adjacent side liquid cooling plates, and one of the first communicating channels is provided at the bottom of the side liquid cooling plate;

[0020] The bottom end of each second communication channel on the liquid cooling plate is communicated with the first communication channel located at the bottom of the side liquid cooling plate.

[0021] Beneficial effect: Each second connecting channel is connected to the first connecting channel, so that the cooling medium located in the bottom liquid cooling plate can flow into the side liquid cooling plate along multiple second connecting channels, thereby ensuring the temperature balance of the bottom and side of each battery cell and improving the safety of battery cell use.

[0022] In an optional embodiment, the bottom liquid cooling plate and the plurality of side liquid cooling plates are integrally formed; and / or,

[0023] A plurality of battery core units are provided on the lower shell.

[0024] In an optional embodiment, two explosion-proof valves are provided at the bottom of each battery cell, and the exhaust holes are provided in a one-to-one correspondence with the explosion-proof valves.

[0025] Beneficial effect: By setting the explosion-proof valve at the bottom of the battery cell corresponding to the exhaust hole of the bottom liquid cooling plate, the high-temperature flue gas of the battery cell is discharged from the exhaust hole into the bottom exhaust cavity and then into the atmosphere through the side exhaust cavity.

[0026] In an optional embodiment, the lower shell includes a frame with a hollow interior, and a bottom guard plate provided at the bottom of the frame and convex downwardly;

[0027] The frame is provided with a mounting portion located above the bottom guard plate, the mounting portion is used to mount the bottom liquid cooling plate, and the bottom exhaust cavity is formed between the bottom guard plate and the bottom liquid cooling plate.

[0028] In an optional embodiment, side beams are respectively provided around the frame, and the mounting portion is relatively provided at the bottom of the two side beams.

[0029] The side exhaust cavity is formed in the side beam, a connecting cavity is provided in the mounting portion, and the connecting cavity is used to connect the bottom exhaust cavity and the side exhaust cavity.

[0030] Beneficial effects: Side beams are arranged around the frame, and the side exhaust cavity is formed in the side beam. The bottom exhaust cavity and the side exhaust cavity are connected through the connecting cavity, which can effectively discharge more smoke out of the battery pack, reduce the pressure in the battery pack during thermal runaway, and avoid battery pack explosion.

[0031] In an optional embodiment, the mounting portion is provided with a plurality of first cavities spaced apart along its width direction, and the side beam is provided with a plurality of second cavities spaced apart along its height direction;

[0032] The plurality of first cavities that are connected to each other constitute the connected cavity body, and the plurality of second cavities that are connected to each other constitute the side exhaust cavity.

[0033] In a second aspect, the present application also provides an electrical device, which is equipped with the battery pack described above.

[0034] Beneficial effect: By providing the battery pack as described above, the temperature balance of the battery cells inside the battery pack can be improved, damage to the battery cells caused by local excessive temperature can be avoided, and the battery pack can have better gas discharge capacity, thereby ensuring the safety of the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0036] FIG1 is a schematic diagram of the three-dimensional structure of a battery pack according to an embodiment of the present application;

[0037] FIG2 is a schematic diagram of the three-dimensional structure of the cooling structure according to an embodiment of the present application;

[0038] FIG3 is a schematic diagram of the connection between the cooling structure and the battery cell according to an embodiment of the present application;

[0039] FIG4 is a schematic diagram of the three-dimensional structure of the frame according to an embodiment of the present application;

[0040] FIG5 is a schematic cross-sectional view of the battery pack according to an embodiment of the present application, taken along the X direction in the middle of the battery cell;

[0041] FIG6 is a partial enlarged view of point I in FIG3;

[0042] FIG7 is a schematic diagram of a partial connection structure between the first communicating channel and the second communicating channel according to an embodiment of the present application;

[0043] FIG8 is a schematic diagram of the connection structure between the frame, the battery cell, and the lower housing according to an embodiment of the present application;

[0044] FIG9 is a schematic diagram of the cross-sectional structure of the mounting portion and the side beam according to an embodiment of the present application.

[0045] Description of reference numerals:

[0046] 1-lower housing; 2-battery unit; 3-cooling structure; 4-exhaust structure;

[0047] 101-frame; 102-bottom guard plate;

[0048] 201-battery cell;

[0049] 301- bottom liquid cooling plate; 302- side liquid cooling plate;

[0050] 401- bottom exhaust chamber; 402- side exhaust chamber;

[0051] 1011-installation part; 1012-side beam; 1013-first cavity; 1014-second cavity; 1015-vent; 1016-vent;

[0052] 3011-first communication channel; 3012-exhaust hole;

[0053] 3021-second connecting channel; 3022-third connecting channel. DETAILED DESCRIPTION

[0054] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of this application.

[0055] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0056] This embodiment relates to a battery pack, which includes a lower housing 1, a battery unit 2 consisting of multiple battery cells 201 arranged side by side, a cooling structure 3, and an exhaust structure 4. The cooling structure 3 includes a bottom liquid cooling plate 301 disposed on the lower housing 1, and multiple side liquid cooling plates 302 disposed side by side on the bottom liquid cooling plate 301. The bottom liquid cooling plate 301 and two adjacent side liquid cooling plates 302 define a mounting space for a single battery cell 201, and the explosion-proof valve of each battery cell 201 is positioned toward the bottom liquid cooling plate 301.

[0057] In addition, the exhaust structure 4 includes a bottom exhaust chamber 401 formed between the bottom liquid cooling plate 301 and the lower shell 1, and a side exhaust chamber 402 formed on the side of the lower shell 1 and used to connect the bottom exhaust chamber 401 and the atmosphere. The bottom liquid cooling plate 301 is provided with exhaust holes 3012 corresponding to the explosion-proof valves, and the exhaust holes 3012 are connected to the bottom exhaust chamber 401.

[0058] The battery pack of this embodiment has a bottom liquid cooling plate 301 disposed on the lower housing 1, and side liquid cooling plates 302 arranged side by side above the bottom liquid cooling plate 301. The side liquid cooling plates 302 are positioned between two adjacent battery cells 201, thereby increasing the heat transfer area, thereby rapidly heating or cooling the internal temperature of the battery cells 201 and achieving temperature uniformity across the battery cells 201. Furthermore, a bottom exhaust chamber 401 is provided between the bottom liquid cooling plate 301 and the lower housing 1, as well as a side exhaust chamber 402 connecting the bottom exhaust chamber 401 to the atmosphere. This allows high-temperature flue gas to be discharged from the bottom exhaust chamber 401 into the side exhaust chamber 402 and then into the atmosphere, preventing the accumulation of high-temperature flue gas within the battery pack and improving battery pack safety.

[0059] Based on the above overall concept, an exemplary structure of the battery pack of this embodiment is shown in Figure 1. The battery pack mainly consists of a lower housing 1 and a battery unit 2 arranged from bottom to top. The battery unit 2 is composed of multiple battery cells 201 arranged in parallel, with a side liquid cooling plate 302 located between every two battery cells 201. The bottom of each battery cell 201 abuts against the bottom liquid cooling plate 301.

[0060] As shown in Figures 1 and 2, the cooling structure 3 of this embodiment consists of a bottom liquid cooling plate 301 and multiple side liquid cooling plates 302, which are arranged perpendicular to each other. The side liquid cooling plates 302 are welded to the bottom liquid cooling plate 301 or integrally formed. As shown in Figure 1, the battery cells 201 of this embodiment use short blade battery cells 201. To increase the capacity of the battery cells 201, as shown in Figure 2, the battery cells 201 of this embodiment are four integrated modules arranged in a rectangular array on the bottom liquid cooling plate 301.

[0061] The battery cells 201 of each integrated module are arranged in multiple rows along the lengthwise X-direction of the bottom liquid cooling plate 301. In this embodiment, the number of battery cells 201 is not limited and can be adjusted as needed. The structural arrangement of the cooling structure 3 can be adaptively adjusted according to the number of battery cells 201.

[0062] Preferably, the bottom liquid cooling plate 301 of this embodiment is provided with a first liquid inlet channel and a first liquid outlet channel disposed opposite each other, as well as a plurality of first connecting channels 3011 disposed between the first liquid inlet channel and the first liquid outlet channel for connecting the two. The first liquid inlet channel is used to input cooling medium into each first connecting channel 3011, and the first liquid outlet channel is used to output cooling medium from each first connecting channel 3011.

[0063] As a specific implementation of this embodiment, the bottom liquid cooling plate 301 has a first liquid inlet channel and a first liquid outlet channel. The first liquid inlet channel is connected to the outlet of an external cooling device or heating device, and the first liquid outlet channel is used to connect to the inlet of the external cooling device, thereby forming a circulating cooling channel or heating channel, improving the cooling effect of the bottom liquid cooling plate.

[0064] Preferably, based on the state shown in Figure 6, a plurality of second connecting channels 3021 are arranged at intervals along the length direction of the side liquid cooling plate 302, and the second connecting channels 3021 extend along the height direction of the side liquid cooling plate 302, and the bottom end of each second connecting channel 3021 is connected to one of the adjacent first connecting channels 3011.

[0065] In addition, it should be pointed out that, as shown in Figures 2 and 6, the second connecting channel 3021 is a long hole arranged along the height direction of the side liquid cooling plate 302, and a third connecting channel 3022 is also provided along the length direction of the side liquid cooling plate 302, which is vertically connected to the second connecting channel 3021, and multiple third connecting channels 3022 are arranged at intervals along the height direction.

[0066] The first connecting channel 3011 communicates with the second connecting channel 3021 and the third connecting channel 3022, enabling communication between the bottom liquid cooling plate 301 and the side liquid cooling plate 302. This allows the cooling medium to flow through the sides and bottom of the battery cells 201, increasing the heat transfer area and facilitating temperature uniformity across the battery cells 201. Furthermore, the provision of multiple second connecting channels 3021 on the side liquid cooling plate 302 facilitates the cooling medium to flow in multiple directions along the length of the side liquid cooling plate 302, enhancing the cooling effect.

[0067] As a feasible embodiment, multiple first connecting channels 3011 are provided between adjacent side liquid cooling plates 302, with one first connecting channel 3011 located at the bottom of the side liquid cooling plate 302. The bottom ends of the second connecting channels 3021 on the side liquid cooling plates 302 are connected to the first connecting channels 3011 located at the bottom of the side liquid cooling plates 302. Specifically, as shown in Figures 2 and 7, the first connecting channels 3011 of this embodiment are located directly below the side liquid cooling plates 302 and in the middle between the two side liquid cooling plates 302. This arrangement further increases the heat transfer area of ​​the bottom liquid cooling plate 301 and improves the heat transfer effect at the bottom.

[0068] To improve the exhaust function of the explosion-proof valves in the battery cells 201, two explosion-proof valves are provided at the bottom of each battery cell 201 in this embodiment, with exhaust holes 3012 corresponding to each explosion-proof valve. Specifically, as shown in Figures 1 to 4, an explosion-proof valve is provided on the side of the battery cell 201 facing the bottom liquid cooling plate 301, and two explosion-proof valves are arranged in parallel on the side of each battery cell 201 to improve exhaust efficiency and quickly alleviate thermal runaway. Furthermore, by correspondingly providing the explosion-proof valves at the bottom of the battery cell 201 with the exhaust holes 3012 in the bottom liquid cooling plate 301, high-temperature flue gas from the battery cell 201 can be discharged from the exhaust holes 3012 into the bottom exhaust chamber 401, and then into the atmosphere through the side exhaust chamber 402.

[0069] To facilitate the installation of cooling structure 3, lower housing 1 includes a hollow frame 101 and a bottom guard plate 102, positioned downwardly and convexly at the bottom of frame 101. Frame 101 is provided with a mounting portion 1011, located above bottom guard plate 102. Mounting portion 1011 is used to mount bottom liquid cooling plate 301. Bottom exhaust cavity 401 is formed between bottom guard plate 102 and bottom liquid cooling plate 301. Specifically, as shown in Figure 4, frame 101 is formed into a rectangular parallelepiped structure with a notch at the bottom.

[0070] Still as shown in Figures 4 and 5, a mounting portion 1011 extends from the inner cavity of the frame 101 toward the middle. The bottom of the bottom liquid cooling plate 301 is mounted on the mounting portion 1011. As mentioned above, this embodiment is an integrated module with four battery cells 201. Cross-shaped horizontal and vertical beams are provided in the middle of the frame 101. The vertical beams extend along the X-direction, and the bottom of the vertical beams is cross-connected to the horizontal beams. Two mounting portions 1011 are provided on either side of the lower end of the vertical beams. The horizontal and vertical beams divide the bottom of the frame 101 into four gaps.

[0071] Furthermore, side beams 1012 are provided around the frame 101, and mounting portions 1011 are provided at the bottoms of the two side beams 1012. The side exhaust cavities 402 are formed within the side beams 1012, and a connecting cavity is provided within the mounting portion 1011, and the connecting cavity is used to connect the bottom exhaust cavity 401 and the side exhaust cavity 402. Specifically, as shown in Figures 4 and 5, the side beams 1012 and the mounting portion 1011 form an L-shape, thereby enclosing a hollow cavity to facilitate the installation of the cooling structure 3.

[0072] In addition, as shown in Figures 1 and 8, the bottom guard plate 102 of this embodiment is formed into a flat plate-like structure, and its shape is adapted to the shape of the frame 101. There are upwardly protruding ribs on both sides of the bottom guard plate 102, and the middle part of the bottom guard plate 102 is concave relative to the ribs. The cavity formed between the concave part and the bottom liquid cooling plate 301 is the bottom exhaust cavity 401. In addition, the side exhaust cavity 402 is formed in the side beam 1012, and the bottom exhaust cavity 401 and the side exhaust cavity 402 are connected by a connecting cavity, which can effectively discharge more smoke out of the battery pack, reduce the pressure in the battery pack during thermal runaway, and avoid battery pack explosion.

[0073] Furthermore, the mounting portion 1011 is provided with a plurality of first cavities 1013 arranged at intervals along its own width direction, and the side beam 1012 is provided with a plurality of second cavities 1014 arranged at intervals along its own height direction. The plurality of first cavities 1013 arranged in a connected manner constitute a connected cavity body, and the plurality of second cavities 1014 arranged in a connected manner constitute a side exhaust cavity 402.

[0074] In terms of specific structure, as shown in Figures 8 and 9, the installation part 1011 is connected to the side beam 1012 and is formed as one piece, and a accommodating cavity is formed inside the two. The installation part 1011 is divided into two first cavities 1013 by a partition. The first cavity 1013 near the middle of the accommodating cavity has a vent 1015 provided at the bottom, and the partition between the two adjacent first cavities 1013 has a vent 1016 for the circulation of high-temperature flue gas.

[0075] Still as shown in FIG9 , in this embodiment, four second cavities 1014 are arranged along the height direction of the side beam 1012. The lowest second cavity 1014 is located at the intersection of the mounting portion 1011 and the side beam 1012. Two adjacent second cavities 1014 are separated by a partition, and the partition is also formed with a vent hole 1016. In this embodiment, the side exhaust cavity 402 is formed as multiple interconnected second cavities 1014. In addition, a vent hole 1016 is also provided on the side surface of one of the second cavities 1014, which is connected to the atmosphere.

[0076] As indicated by the arrows in FIG8 , the high-temperature flue gas released from the explosion-proof valve of the battery cell 201 enters the bottom exhaust cavity 401 through the exhaust hole 3012, then enters the mounting portion 1011 through the vent 1015 provided on the first cavity 1013, and passes into the second cavity 1014, and then enters the atmosphere through the vent 1016 connected to the atmosphere, thereby achieving the purpose of releasing the high-temperature gas in the battery pack.

[0077] The battery pack of this embodiment features a bottom liquid cooling plate 301 and side liquid cooling plates 302 disposed above the lower housing 1. The side liquid cooling plates 302 are positioned between two adjacent battery cells 201 to increase the heat transfer area, enabling rapid heating or cooling of the internal temperature of the battery cells 201 and achieving temperature uniformity across the battery cells 201. Furthermore, a bottom exhaust cavity 401 is provided between the bottom liquid cooling plate 301 and the lower housing 1, as well as a side exhaust cavity 402 connecting the bottom exhaust cavity 401 to the atmosphere. This allows high-temperature fumes to be discharged from the bottom exhaust cavity 401 into the side exhaust cavity 402 and then into the atmosphere, preventing the accumulation of high-temperature fumes within the battery pack and improving battery pack safety.

[0078] This embodiment also relates to an electrical device, in which the above-mentioned battery pack is installed.

[0079] The electrical device of this embodiment, by providing the above-mentioned battery pack, can improve the temperature balance of the battery cells 201 inside the battery pack, avoid damage to the battery cells 201 caused by local excessive temperature, and enable the battery pack to have better air discharge capacity, thereby ensuring the safety of the electrical device.

[0080] Although the embodiments of the present application have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations shall fall within the scope defined by the appended claims. Industrial Applicability

[0081] The battery pack described in this application utilizes a bottom liquid cooling plate disposed on the lower housing and side liquid cooling plates disposed above the bottom liquid cooling plate. The side liquid cooling plates are positioned between adjacent battery cells to increase the heat transfer area, thereby rapidly heating or cooling the internal temperature of the battery cells and achieving temperature uniformity across the entire battery cell. Furthermore, a bottom exhaust chamber is provided between the bottom liquid cooling plate and the lower housing, as well as a side exhaust chamber connecting the bottom exhaust chamber to the atmosphere. This allows high-temperature flue gas to be discharged from the bottom exhaust chamber into the side exhaust chamber and then into the atmosphere, preventing the accumulation of high-temperature flue gas within the battery pack and improving battery pack safety.

Claims

1. A battery pack, characterized in that: It includes a lower shell, a battery unit consisting of a plurality of battery cells arranged side by side, a cooling structure and an exhaust structure; The cooling structure includes a bottom liquid cooling plate arranged on the lower shell, and a plurality of side liquid cooling plates arranged side by side on the bottom liquid cooling plate, and an installation space for a single battery cell is defined between the bottom liquid cooling plate and two adjacent side liquid cooling plates, and an explosion-proof valve of each battery cell is arranged toward the bottom liquid cooling plate; The exhaust structure includes a bottom exhaust cavity formed between the bottom liquid cooling plate and the bottom of the lower shell, and a side exhaust cavity formed on the side of the lower shell and used to connect the bottom exhaust cavity and the atmosphere. The bottom liquid cooling plate is provided with exhaust holes corresponding to the explosion-proof valves, and the exhaust holes are connected to the bottom exhaust cavity.

2. The battery pack according to claim 1, characterized in that: The bottom liquid cooling plate is provided with a first liquid inlet channel and a first liquid outlet channel which are arranged opposite to each other, and a plurality of first connecting channels which are arranged between the first liquid inlet channel and the first liquid outlet channel and are used to connect the two; The first liquid inlet channel is used to input the cooling medium into each of the first connecting channels; The first liquid outlet channel is used to output the cooling medium in each of the first connecting channels to the outside.

3. The battery pack according to claim 2, characterized in that: The side liquid cooling plate is provided with a plurality of second communication channels arranged at intervals along its length direction; The bottom end of each of the second communication channels is communicated with one of the adjacent first communication channels.

4. The battery pack according to claim 3, characterized in that: A plurality of the first communicating channels are provided between two adjacent side liquid cooling plates, and one of the first communicating channels is provided at the bottom of the side liquid cooling plate; The bottom end of each of the second communication channels on the side liquid cooling plate is communicated with the first communication channel located at the bottom of the side liquid cooling plate.

5. The battery pack according to claim 1, characterized in that: The bottom liquid cooling plate and the plurality of side liquid cooling plates are integrally formed; and / or, A plurality of the battery core units are arranged on the lower shell.

6. The battery pack according to claim 1, characterized in that: Two explosion-proof valves are provided at the bottom of each battery cell, and the exhaust holes are provided in one-to-one correspondence with the explosion-proof valves.

7. The battery pack according to any one of claims 1 to 6, characterized in that: The lower shell includes a frame with a hollow interior, and a bottom guard plate disposed at the bottom of the frame and convexly arranged downward; The frame is provided with a mounting portion located above the bottom guard plate, the mounting portion is used to mount the bottom liquid cooling plate, and the bottom exhaust cavity is formed between the bottom guard plate and the bottom liquid cooling plate.

8. The battery pack according to claim 7, characterized in that: Side beams are respectively arranged around the frame, and the mounting portion is relatively arranged at the bottom of the two side beams. The side exhaust cavity is formed in the side beam, a connecting cavity is provided in the mounting portion, and the connecting cavity is used to connect the bottom exhaust cavity and the side exhaust cavity.

9. The battery pack according to claim 8, characterized in that: The mounting portion is provided with a plurality of first cavities spaced apart along its width direction, and the side beam is provided with a plurality of second cavities spaced apart along its height direction; A plurality of the first cavities that are connected to each other constitute the connected cavity, and a plurality of the second cavities that are connected to each other constitute the side exhaust cavity.

10. An electrical device, characterized in that: The electrical device is provided with a battery pack according to any one of claims 1 to 9.

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