Battery pack

Abstract

The utility model provides a battery pack which comprises a shell and a battery cell module, the shell comprises a bottom plate and a side plate, the bottom plate and the side plate enclose to form an accommodating cavity, the surface, facing the accommodating cavity, of the bottom plate is provided with at least one convex rib, the battery cell module is fixed in the accommodating cavity through structural adhesive, the battery cell module comprises a plurality of rows of battery cells and a plurality of liquid cooling plates, a liquid cooling plate is arranged between at least every two rows of battery cells, the two rows of battery cells and the liquid cooling plate are fixed through heat-conducting glue, the battery cells are erected on the convex ribs, and pressure release valves of the battery cells are arranged between the convex ribs. According to the battery pack disclosed by the utility model, not only can the use of peripheral structural members such as a battery cell tray and a plastic bracket be reduced, the total weight of the battery pack be reduced, the energy density of the battery pack be improved and the production cost of the battery pack be reduced, but also the influence of battery cell thermal runaway on other battery cells which are not subjected to thermal runaway can be reduced, and the safety of the battery pack is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery pack. Background Art

[0002] As people's environmental awareness continues to increase, replacing fossil fuel-driven vehicles with electric vehicles to achieve zero emissions and zero pollution has become one of the development trends of electric vehicles in the future. Among them, the battery pack is the core power source of electric vehicles.

[0003] The battery pack of the related art usually encapsulates the battery cells into battery modules through peripheral structural parts such as battery trays and plastic brackets, and then integrates the modules into the battery case as units. This arrangement not only increases the total weight of the battery pack, resulting in low energy density of the battery pack, but also increases the production cost of the battery pack. Utility Model Content

[0004] The embodiments of the present utility model provide a battery pack, which can reduce the total weight of the battery pack, improve the energy density of the battery pack and reduce the production cost of the battery pack.

[0005] An embodiment of the utility model provides a battery pack, comprising:

[0006] A shell, the shell comprising a bottom plate and side plates connected to the periphery of the bottom plate, the bottom plate and the side plates enclose a receiving cavity, and the surface of the bottom plate facing the receiving cavity is provided with at least one convex rib;

[0007] The battery cell module is fixed in the accommodating cavity by structural adhesive. The battery cell module includes multiple rows of battery cells and a plurality of liquid cooling plates. At least one liquid cooling plate is arranged between every two rows of battery cells. The two rows of battery cells and one liquid cooling plate are fixed by thermal conductive adhesive. The battery cells are mounted on convex ribs, and the pressure relief valve of the battery cells is arranged between the convex ribs.

[0008] In one embodiment, a plurality of first pressure relief channels are formed between the bottom plate and the convex ribs, and the battery cells and the structural adhesive are sealed and covered on the plurality of first pressure relief channels.

[0009] In one embodiment, the battery cell module further includes a flame retardant layer, which is fixed to the convex rib by structural adhesive, and multiple rows of the battery cells and a plurality of the liquid cooling plates are fixed to a side of the flame retardant layer away from the convex rib by structural adhesive.

[0010] In one embodiment, the battery cell is a cylindrical battery cell and the side wall of the battery cell is matched with the side wall of the liquid cooling plate, and the side wall of the battery cell and the side wall of the liquid cooling plate are bonded and fixed by thermal conductive adhesive.

[0011] In one embodiment, a cover plate is further included, wherein the cover plate is fixed to a side of the side plate away from the bottom plate, and a glue injection hole is provided on the cover plate.

[0012] In one embodiment, a battery management system and a battery cut-off unit are further included, and a partition beam is provided on the surface of the bottom plate facing the accommodating cavity, and the partition beam divides the bottom plate into a first area and a second area. The rib is provided in the first area, and the battery management system and the battery cut-off unit are fixed to the second area by structural adhesive.

[0013] In one embodiment, a positioning boss is provided in the second area, and the positioning boss is configured to position the battery management system and the battery cut-off unit.

[0014] In one embodiment, the side plate is provided with a plurality of first pressure relief ports corresponding to the plurality of first pressure relief channels, and each of the first pressure relief channels is communicated with the first pressure relief port corresponding to it.

[0015] In one embodiment, a second pressure relief port is further provided on the side plate, an explosion-proof valve is provided at the second pressure relief port, a second pressure relief channel is provided in the side plate, a plurality of the first pressure relief ports are connected to the second pressure relief channel, and the second pressure relief channel is connected to the second pressure relief port.

[0016] In one embodiment, the side panel includes a first side panel, a second side panel and two third side panels arranged opposite to each other, the first side panel is arranged opposite to the second side panel, the two ends of the two third side panels are respectively connected to the first side panel and the second side panel, the first pressure relief port is arranged on the inner side wall of the second side panel, and the second pressure relief port is arranged on the outer side wall of the first side panel.

[0017] In one embodiment, the first side plate, the second side plate and the two third side plates are all hollow, the internal spaces of the two third side plates are connected to the internal space of the first side plate and the internal space of the second side plate, and the internal spaces of the first side plate, the second side plate and the two third side plates jointly form the second pressure relief channel.

[0018] Beneficial effects of the embodiments of the utility model:

[0019] In an embodiment of the utility model, the battery cell module is fixed in the accommodating cavity by structural adhesive, and the battery cell and the liquid cooling plate are fixed by thermal conductive adhesive, which can reduce the use of peripheral structural parts such as battery cell trays and plastic brackets, reduce the total weight of the battery pack, improve the energy density of the battery pack and reduce the production cost of the battery pack; the battery cell is mounted on the ribs, and the pressure relief valve of the battery cell is arranged between the ribs, which can prevent the flame generated by thermal runaway of the battery cell from spraying to an adjacent row of battery cells, reduce the impact of thermal runaway of the battery cell on other battery cells that have not experienced thermal runaway, and improve the safety of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 is an exploded schematic diagram of a battery pack provided in an embodiment of the utility model;

[0022] Figure 2 It is a schematic diagram of the structure of a battery pack with assembled battery cell modules provided in an embodiment of the utility model;

[0023] Figure 3 It is a partial enlarged schematic diagram of a battery cell module provided by an embodiment of the utility model;

[0024] Figure 4 The embodiment of the utility model provides Figure 3 A partial enlarged schematic diagram of point B in the middle;

[0025] Figure 5 It is a structural schematic diagram of a housing provided by an embodiment of the utility model;

[0026] Figure 6 The embodiment of the utility model provides Figure 5 A local enlarged schematic diagram of the middle A;

[0027] Figure 7 It is a schematic diagram of the structure of a battery pack equipped with a battery management system and a battery disconnection unit provided in an embodiment of the utility model;

[0028] Figure 8 It is a structural schematic diagram of a side plate provided by an embodiment of the utility model;

[0029] Fig. 9 It is a structural schematic diagram of the second side plate provided in an embodiment of the utility model.

[0030] The following are the descriptions of the reference numerals:

[0031] 10. Shell; 20. Battery cell module; 30. Cover plate; 40. Battery management system; 50. Battery cut-off unit; 60. Explosion-proof valve; 70. Foam glue; 11. Bottom plate; 12. Side plate; 13. Raised rib; 14. Partition beam; 15. Positioning boss; 21. Battery cell; 22. Liquid cooling plate; 23. Flame retardant layer; 24. Structural glue; 25. Structural glue; 31. Glue filling hole; 111. First area; 112. Second area; 121. First pressure relief port; 122. Second pressure relief port; 123. First side plate; 124. Second side plate; 125. Third side plate. DETAILED DESCRIPTION

[0032] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved more clearly, the technical solutions of the present invention are further explained below with reference to the accompanying drawings and through specific implementation methods.

[0033] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the present utility model, unless otherwise clearly specified and limited, the first feature "above" or "below" the second feature may include the first and second features directly contacting, or may include the first and second features not directly contacting but contacting through another feature between them. Moreover, the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature. In the description of this embodiment, the terms "above", "below", "left" and "right" and other directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation to the present utility model. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0035] The inventors have discovered through research that battery packs of related art usually encapsulate battery cells into battery modules through peripheral structural parts such as battery trays and plastic brackets, and then integrate the modules into a battery case as units. This arrangement has at least the following problems: ① Peripheral structural parts such as battery trays and plastic brackets greatly increase the total weight of the battery pack, resulting in low energy density of the battery pack; ② Peripheral structural parts such as battery trays and plastic brackets not only increase the production cost of the battery pack, but also complicate the assembly process of the battery pack, greatly increasing the labor cost of assembling the battery pack.

[0036] In order to solve the above problems, Figures 1 to 9 As shown, this embodiment provides a battery pack, which includes: a shell 10 and a battery cell module 20, wherein the shell 10 includes a bottom plate 11 and a side plate 12 connected to the periphery of the bottom plate 11, the bottom plate 11 and the side plate 12 enclose a receiving cavity, and at least one convex rib 13 is provided on the surface of the bottom plate 11 facing the receiving cavity, the battery cell module 20 is fixed in the receiving cavity by structural adhesive, the battery cell module 20 includes multiple rows of battery cells 21 and a plurality of liquid cooling plates 22, a liquid cooling plate 22 is provided between at least every two rows of battery cells 21, two rows of battery cells 21 and a liquid cooling plate 22 are fixed by thermal conductive adhesive, the battery cells 21 are mounted on the convex rib 13, and the pressure relief valve of the battery cells 21 is provided between the convex ribs 13.

[0037] The battery pack in this embodiment fixes the cell module 20 in the accommodating cavity by structural adhesive, and fixes the cell 21 and the liquid cooling plate 22 by thermal conductive adhesive, which can reduce the use of peripheral structural parts such as cell trays and plastic brackets, reduce the total weight of the battery pack, improve the energy density of the battery pack and reduce the production cost of the battery pack. In addition, the cell 21 is mounted on the convex ribs 13, and the pressure relief valve of the cell 21 is set between the convex ribs 13, which can prevent the flame generated by the thermal runaway of the cell 21 from spraying to the adjacent row of cells 21, reduce the impact of the thermal runaway of the cell 21 on other cells 21 that have not experienced thermal runaway, and improve the safety of the battery pack.

[0038] In some embodiments, a plurality of first pressure relief channels are formed between the bottom plate 11 and the convex rib 13, and the battery cells 21 and the structural adhesive seal cover the plurality of first pressure relief channels. Such a configuration can form a plurality of independent first pressure relief channels, thereby preventing the flame generated by thermal runaway of the battery cell 21 from spraying onto an adjacent row of battery cells 21, reducing the impact of thermal runaway of the battery cell 21 on other battery cells 21 that have not experienced thermal runaway, and improving the safety of the battery pack.

[0039] In some embodiments, the side panel 12 is formed by welding aluminum extrusions, and the bottom plate 11 and the side panel 12 are fixed by stir friction welding. The side panel 12 is fixed to the bottom plate 11 by stir friction welding, which can not only reduce the deformation of the shell 10 caused by the connection, but also avoid the accumulation of welding slag affecting the assembly.

[0040] In some embodiments, continue to refer to Figure 1 As shown, the battery module 20 also includes a flame retardant layer 23, which is fixed to the rib 13 by structural adhesive, and multiple rows of battery cells 21 and a number of liquid cooling plates 22 are fixed to the side of the flame retardant layer 23 away from the rib 13 by structural adhesive 24. When the battery cell 21 has thermal runaway, the high-temperature gas and flame generated by the thermal runaway break through the pressure relief valve and the flame retardant layer 23, gather in the first pressure relief channel, and are led out of the battery pack through the first pressure relief channel. Since the pressure relief valve of the adjacent battery cell 21 that has not experienced thermal runaway is blocked by the flame retardant layer 23, other battery cells 21 that have not experienced thermal runaway can be unaffected by the high-temperature gas and flame, thereby avoiding the occurrence of chain thermal runaway.

[0041] During the specific battery pack assembly process, a tooling fixture can be used to first bond and fix the side walls of the battery cell 21 and the side walls of the liquid cooling plate 22 with thermal conductive adhesive, and then a layer of structural adhesive is applied to the bottom surfaces of the battery cell 21 and the liquid cooling plate 22. The flame retardant layer 23 is then fixed to the bottom surfaces of the battery cell 21 and the liquid cooling plate 22 with the structural adhesive to form a battery cell module 20. Subsequently, structural adhesive is applied to the edge of the bottom plate 11 and the ribs 13, and the battery cell module 20 is placed on the bottom plate 11. Pressure is applied to the battery cell module 20 through the tooling until the structural adhesive solidifies.

[0042] It should be noted that the flame retardant layer 23 can be formed by splicing a plurality of flame retardant sub-layers, that is, a flame retardant sub-layer can be arranged corresponding to one or more battery cells 21, so that a single damaged flame retardant sub-layer can be replaced later. Furthermore, the material of the flame retardant layer 23 is mica. The flame retardant layer 23 made of mica can not only ensure the fireproof performance, but also effectively avoid the thickness of the flame retardant layer 23 being too thick. Of course, the material of the flame retardant layer 23 can also be other materials with flame retardant effects. The material selection of the flame retardant layer 23 can be determined according to the UL94-V0 flame retardant grade, and this application does not impose any restrictions on this.

[0043] In some embodiments, reference Figures 2 to 4 As shown, the liquid cooling plate 22 is a serpentine liquid cooling plate, the battery cell 21 is a cylindrical battery cell 21, the side wall of the battery cell 21 is adapted to the side wall of the liquid cooling plate 22, the side wall of the battery cell 21 and the side wall of the liquid cooling plate 22 are bonded and fixed by a thermal conductive adhesive 25, the liquid cooling plate 22 is set as a serpentine liquid cooling plate and is arranged between two rows of battery cells 21, when the coolant flows through the internal flow channel of the liquid cooling plate 22, the liquid cooling plate 22 can cool and dissipate heat for the two rows of battery cells 21 at the same time, and the cooling efficiency is greatly improved.

[0044] In some embodiments, continue to refer to Figure 1As shown, the battery pack also includes a cover plate 30, which is fixed to a side of the side plate 12 away from the bottom plate 11. The cover plate 30 may be a sheet metal stamping structure. The cover plate 30 covers the upper opening of the shell 10, thereby protecting the components inside the shell 10 and preventing damage to the components inside the shell 10.

[0045] In some embodiments, a groove is provided on a side of the side panel 12 away from the bottom panel 11. When the cover panel 30 is fixed to the side of the side panel 12 away from the bottom panel 11, sealant can be applied in the groove, and then the cover panel 30 is installed on the side of the side panel 12 away from the bottom panel 11, and pressure is applied to the cover panel 30 with a tool until the sealant solidifies. The cover panel 30 is fixed to the side panel 12 by the sealant, which can reduce the complexity of the assembly process of the battery pack and reduce the labor cost of assembling the battery pack.

[0046] Further, continue to refer to Figure 1 As shown, a glue injection hole 31 is provided on the cover plate 30. After the cover plate 30 is fixed to the side of the side plate 12 away from the bottom plate 11, the foam glue 70 can be injected into the accommodating cavity through the glue injection hole 31. After the excess foam glue 70 overflows from the glue injection hole 31, sealant is applied to the glue injection port for sealing and waterproofing. By injecting the foam glue 70 into the accommodating cavity, all the components in the accommodating cavity can be solidified into a whole, thereby enhancing the strength of the battery pack and preventing the internal components of the battery pack from loosening. In addition, the foam glue 70 can improve the insulation between the internal components of the battery pack and prevent the components from short circuiting.

[0047] In some embodiments, reference Figure 5 and Figure 7 As shown, the battery pack also includes a battery management system (BMS) 40 and a battery disconnect unit (BDU) 50. A partition beam 14 is also provided on the surface of the bottom plate 11 facing the accommodating cavity. The partition beam 14 separates the bottom plate 11 into a first area 111 and a second area 112. The rib 13 is provided in the first area 111. The battery management system 40 and the battery disconnect unit 50 are fixed to the second area 112 by structural adhesive 24.

[0048] Further, continue to refer to Figure 5As shown, the second area 112 is provided with a positioning boss 15, and the positioning boss 15 is configured to position the battery management system 40 and the battery cut-off unit 50. During the installation of the battery management system 40 and the battery cut-off unit 50, structural adhesive can be applied to the area corresponding to the positioning boss 15 on the bottom plate 11, and then the battery management system 40 and the battery cut-off unit 50 are installed in the area corresponding to the positioning boss 15, and tooling is used to apply pressure to the battery management system 40 and the battery cut-off unit 50 until the structural adhesive solidifies. By fixing the battery management system 40 and the battery cut-off unit 50 with the structural adhesive, the use of bolts can be reduced, thereby reducing the labor cost of assembling the battery pack.

[0049] In some embodiments, reference Figures 5 to 9 As shown, the side plate 12 is provided with a plurality of first pressure relief ports 121 corresponding to the plurality of first pressure relief channels, and the plurality of first pressure relief ports 121 are arranged at one end of the side plate 12 close to the bottom plate 11, and each first pressure relief channel is connected to the first pressure relief port 121 corresponding to it. Figure 5 As shown, the convex rib 13 divides the pressure relief cavity into 13 independent first pressure relief channels, and the side plate 12 is provided with 13 first pressure relief ports corresponding to the 13 first pressure relief channels respectively.

[0050] In some embodiments, continue to refer to Figures 5 to 9 As shown, a second pressure relief port 122 is further provided on the side panel 12, an explosion-proof valve 60 is provided at the second pressure relief port 122, a second pressure relief channel is provided in the side panel 12, a plurality of first pressure relief ports 121 are connected to the second pressure relief channel, and the second pressure relief channel is connected to the second pressure relief port 122. When thermal runaway occurs in the battery cell 21, the high-temperature gas and flame gathered in the first pressure relief channel reach the second pressure relief channel through the first pressure relief port 121, and then are guided out of the battery pack through the second pressure relief port 122 by the second pressure relief channel, thereby achieving normal and smooth pressure relief of the battery pack and avoiding thermal runaway of the entire battery pack.

[0051] In some embodiments, continue to refer to Figures 5 to 9 As shown, the side plate 12 includes a first side plate 123, a second side plate 124, and two third side plates 125 arranged oppositely, the first side plate 123 and the second side plate 124 are arranged oppositely, the two ends of the two third side plates 125 are respectively connected to the first side plate 123 and the second side plate 124, the first pressure relief port 121 is arranged on the inner side wall of the second side plate 124, and the second pressure relief port 122 is arranged on the outer side wall of the first side plate 123. For example, the first side plate 123 can be a front side plate, the second side plate 124 is a rear side plate arranged oppositely to the front side plate, the two third side plates 125 are a left side plate and a right side plate arranged oppositely, the first pressure relief port is arranged on the inner side wall of the rear side plate, and the second pressure relief port 122 is arranged on the outer side wall of the front side plate.

[0052] In some embodiments, the second pressure relief port 122 may be provided in plurality, and the plurality of second pressure relief ports 122 are all provided on the outer side wall of the first side plate 123, for example, Figure 5 As shown, two second pressure relief ports 122 are provided, and the two second pressure relief ports 122 are respectively provided at the two ends of the outer wall of the first side plate 123. When thermal runaway occurs in the battery cell 21, the high-temperature gas and flame generated by the thermal runaway can be discharged through the multiple second pressure relief ports 122, thereby increasing the pressure relief speed of the battery pack.

[0053] In some embodiments, the first side plate 123, the second side plate 124 and the two third side plates 125 are all hollow, and the internal spaces of the two third side plates 125 are connected to the internal spaces of the first side plate 123 and the internal spaces of the second side plate 124, and the internal spaces of the first side plate 123, the second side plate 124 and the two third side plates 125 together form a second pressure relief channel. Figure 8 As shown, when thermal runaway occurs in the battery cell 21, the high-temperature gas and flame gathered in the first pressure relief channel reach the inner space of the second side plate 124 through the first pressure relief port 121, and then reach the inner space of the first side plate 123 from the inner space of the second side plate 124 through the inner spaces of the two third side plates 125, and then are guided out of the battery pack from the inner space of the first side plate 123 through the second pressure relief port 122, thereby achieving normal and smooth pressure relief of the battery pack.

[0054] The above is a detailed introduction to the embodiments of the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for technicians in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A battery pack, characterized in that: include: A shell, the shell comprising a bottom plate and side plates connected to the periphery of the bottom plate, the bottom plate and the side plates enclose a receiving cavity, and the surface of the bottom plate facing the receiving cavity is provided with at least one convex rib; The battery cell module is fixed in the accommodating cavity by structural adhesive. The battery cell module includes multiple rows of battery cells and a plurality of liquid cooling plates. At least one liquid cooling plate is arranged between every two rows of battery cells. The two rows of battery cells and one liquid cooling plate are fixed by thermal conductive adhesive. The battery cell is mounted on the convex ribs, and the pressure relief valve of the battery cell is arranged between the convex ribs.

2. The battery pack according to claim 1, characterized in that: A plurality of first pressure relief channels are formed between the bottom plate and the convex ribs, and the battery cells and the structural adhesive seal and cover the plurality of first pressure relief channels.

3. The battery pack according to claim 1, characterized in that: The battery module also includes a flame retardant layer, which is fixed to the convex rib by structural adhesive, and multiple rows of battery cells and a plurality of liquid cooling plates are fixed to a side of the flame retardant layer away from the convex rib by structural adhesive.

4. The battery pack according to claim 1, characterized in that: The battery core is a cylindrical battery core and the side wall of the battery core is matched with the side wall of the liquid cooling plate. The side wall of the battery core and the side wall of the liquid cooling plate are bonded and fixed by heat conductive adhesive.

5. The battery pack according to claim 1, characterized in that: It also includes a cover plate, which is fixed to a side of the side plate away from the bottom plate, and a glue injection hole is provided on the cover plate.

6. The battery pack according to any one of claims 1 to 5, characterized in that: It also includes a battery management system and a battery cut-off unit. A partition beam is provided on the surface of the bottom plate facing the accommodating cavity. The partition beam divides the bottom plate into a first area and a second area. The convex rib is provided in the first area. The battery management system and the battery cut-off unit are fixed to the second area by structural adhesive.

7. The battery pack according to claim 6, characterized in that: The second area is provided with a positioning boss, and the positioning boss is configured to position the battery management system and the battery cut-off unit.

8. The battery pack according to claim 2, characterized in that: The side plate is provided with a plurality of first pressure relief ports corresponding to the plurality of first pressure relief channels respectively, and each of the first pressure relief channels is communicated with the first pressure relief port corresponding to it.

9. The battery pack according to claim 8, characterized in that: The side plate is also provided with a second pressure relief port, an explosion-proof valve is provided at the second pressure relief port, a second pressure relief channel is provided in the side plate, a plurality of the first pressure relief ports are connected to the second pressure relief channel, and the second pressure relief channel is connected to the second pressure relief port.

10. The battery pack according to claim 9, characterized in that: The side panel includes a first side panel, a second side panel and two third side panels arranged opposite to each other, the first side panel is arranged opposite to the second side panel, two ends of the two third side panels are respectively connected to the first side panel and the second side panel, the first pressure relief port is arranged on the inner side wall of the second side panel, and the second pressure relief port is arranged on the outer side wall of the first side panel.

11. The battery pack according to claim 10, characterized in that: The first side plate, the second side plate and the two third side plates are all hollow, the internal spaces of the two third side plates are connected with the internal space of the first side plate and the internal space of the second side plate, and the internal spaces of the first side plate, the second side plate and the two third side plates jointly form the second pressure relief channel.

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