Battery cell and battery pack

Abstract

The invention relates to the technical field of batteries, in particular to a single battery and a battery pack, the single battery comprises a shell and a pole group, a containing cavity for containing the pole group is formed in the shell, the shell comprises a first shell part, a bent shell part and a second shell part which are sequentially arranged in the first direction, and the first shell part and the second shell part are parallel to each other; the first shell part and the second shell part are staggered by a preset distance in the second direction, and the bent shell part is connected with the first shell part and the second shell part. When the plurality of battery cells are stacked in the second direction, two adjacent battery cells abut against each other through the bent shell portions of each other, so that expansion gaps are formed between two adjacent first shell portions and between two adjacent second shell portions. According to the battery monomer and the battery pack provided by the invention, the expansion pressure of the battery pack box body is effectively relieved, the safety of the battery pack is improved, and the sealing performance of the battery pack is ensured.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell and a battery pack. Background Art

[0002] With the development of battery technology, the safety of battery pack use and the energy density of battery pack have become key factors in determining the core competitiveness of batteries.

[0003] However, during the use of the battery, as the battery pack is used for a longer time, the volume of the battery cells in the battery pack will continue to expand. Some types of battery cells even swell and deform greatly, resulting in a very large expansion force acting on the box, often reaching tens or even thousands of Newtons, especially in the module end area. This expansion force poses a huge test to the strength of the box and may even cause the box to crack, which not only affects the sealing of the entire battery pack, but also affects the safety of the battery pack. Summary of the invention

[0004] The purpose of the present application is to provide a battery cell and a battery pack, so as to solve to a certain extent the technical problem existing in the prior art that during the use of the battery, as the use time of the battery pack increases, the volume of the battery cell in the battery pack will continue to expand, and some types of battery cells even expand and deform greatly, resulting in a very large expansion force acting on the box, often reaching tens or thousands of Newtons, especially in the module end area. This expansion force poses a huge test to the strength of the box and may even cause the box to crack, which not only affects the sealing of the entire battery pack, but also affects the safety of the battery pack.

[0005] According to a first aspect of the present application, a battery cell is provided, comprising a shell and an electrode group, wherein a housing cavity for accommodating the electrode group is provided in the shell, wherein the shell comprises a first shell portion, a curved shell portion, and a second shell portion sequentially arranged along a first direction, wherein the first shell portion and the second shell portion are parallel to each other, and the first shell portion and the second shell portion are staggered by a predetermined distance along a second direction, wherein the curved shell portion connects the first shell portion and the second shell portion, and the second direction intersects the first direction;

[0006] When the plurality of battery cells are stacked along the second direction, two adjacent battery cells abut against each other via their bent shell portions, so that an expansion gap is formed between two adjacent first shell portions and between two adjacent second shell portions.

[0007] Preferably, the battery cell includes a first end and a second end opposite to each other in a third direction, and the third direction intersects a plane defined by both the first direction and the second direction;

[0008] The battery cell also includes a first edge portion and a second edge portion, both of which are arranged at a first end of the battery cell, the first edge portion is arranged at an end of the first shell portion in the first direction away from the second shell portion, and the second edge portion is arranged at an end of the second shell portion in the first direction away from the first shell portion.

[0009] Preferably, an exhaust cavity communicating with the accommodating cavity is provided inside the first edge portion and inside the second edge portion;

[0010] An explosion-proof valve is provided on one side of both the first edge portion and the second edge portion facing the second end of the battery cell.

[0011] Preferably, defined in the second direction, relative to the second shell portion, the misalignment direction of the first shell portion is a first misalignment direction, and the opposite direction of the first misalignment direction is a second misalignment direction;

[0012] The first edge portion protrudes by the predetermined distance along the first misalignment direction relative to the end surface of the first shell portion in the first misalignment direction;

[0013] The second edge portion protrudes by the predetermined distance along the second misaligned direction relative to an end surface of the second shell portion in the second misaligned direction.

[0014] According to the second aspect of the present application, a battery pack is provided, comprising a plurality of battery cells as described in any of the above technical solutions, thus having all the beneficial technical effects of the battery cells, which are not described in detail herein. The plurality of battery cells are stacked along the second direction to form a battery module.

[0015] Preferably, it further comprises two side beams extending along the second direction, the battery module is arranged between the two side beams, and the first edge portion and the second edge portion of each battery cell are overlapped with the two side beams respectively;

[0016] An exhaust passage is arranged in the side beam, and the exhaust passages of the two side beams are respectively connected to the explosion-proof valve of the first edge portion and the explosion-proof valve of the second edge portion.

[0017] Preferably, the side beam comprises an inner side wall and an outer side wall which are opposite to each other and spaced apart in the first direction, and the exhaust passage is arranged between the inner side wall and the outer side wall;

[0018] In the third direction, the size of the inner side wall is smaller than that of the outer side wall, so as to form a supporting groove on the inner side of the side beam, and the first edge portion or the second edge portion can be embedded in the supporting groove;

[0019] An exhaust hole communicating with the exhaust channel is disposed on the bottom surface of the supporting groove, and the exhaust hole is disposed corresponding to the explosion-proof valve of the first edge portion or the second edge portion.

[0020] Preferably, a cooling channel extending along the second direction is provided in the inner side wall, one or more cooling channels are provided in the inner side wall, and at least a portion of the battery module is in contact with the inner side wall.

[0021] Preferably, when there are multiple cooling channels, the multiple cooling channels are arranged at intervals along the third direction;

[0022] The side beam further includes a reinforcing rib connecting the inner side wall and the outer side wall;

[0023] The reinforcing rib is arranged between two adjacent cooling channels;

[0024] The reinforcing rib is provided with a vent hole penetrating the reinforcing rib along the third direction.

[0025] Preferably, it also includes:

[0026] Two cross beams extending along the first direction, the two cross beams being respectively connected to two ends of the two side beams to form a frame surrounding the battery module;

[0027] A bottom plate, fixed to the bottom of the frame, for supporting the battery module;

[0028] The liquid cooling plate is arranged between the bottom plate and the battery module.

[0029] Compared with the prior art, the beneficial effects of this application are:

[0030] The battery cell provided in the present application is connected by a curved shell to a first shell and a second shell that are arranged in parallel and staggered in a second direction (i.e., the stacking direction of the battery cells in the battery pack), so that when a plurality of battery cells are stacked along the second direction, two adjacent battery cells abut against each other via each other's curved shell portions to form an expansion gap between the two adjacent first shell portions and between the two adjacent second shell portions. In this way, as the battery cell is used, the volume gradually expands, and the battery pack can use the expansion gap formed between the two adjacent battery cells to release the expansion force of the battery cell, effectively relieve the expansion pressure of the battery pack case, improve the safety of the battery pack, and ensure the sealing of the battery pack.

[0031] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. 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 paying any creative work.

[0033] Figure 1 A schematic diagram of the isometric structure of a battery cell provided in an embodiment of the present application;

[0034] Figure 2 A schematic diagram of the side structure of a battery cell provided in an embodiment of the present application;

[0035] Figure 3 A schematic diagram of the isometric structure of a battery module provided in an embodiment of the present application;

[0036] Figure 4 for Figure 3 The enlarged structural schematic diagram of the battery module provided at A;

[0037] Figure 5 for Figure 3 The enlarged structural schematic diagram of the battery module provided at B;

[0038] Figure 6 for Figure 3 The enlarged structural diagram of the battery module provided at C;

[0039] Figure 7 A schematic diagram of the exploded structure of a battery pack provided in an embodiment of the present application;

[0040] Figure 8 A schematic diagram of the top view of the box provided in an embodiment of the present application;

[0041] Fig. 9 for Figure 8 A schematic diagram of the cross-sectional structure of the provided battery module obtained by cutting along the DD direction;

[0042] Fig.10 for Fig. 9 The enlarged structural schematic diagram of the battery module provided at E;

[0043] Fig.11 A partial schematic diagram of the cross-section structure of a battery pack provided in an embodiment of the present application;

[0044] Fig.12 This is a schematic diagram of the axonometric structure of the box provided in an embodiment of the present application.

[0045] Reference numerals:

[0046] 1-battery cell; 10-expansion gap; 100-battery module; 11-first shell; 12-second shell; 13-bent shell; 131-first convex surface; 132-first concave surface; 133-second convex surface; 134-second concave surface; 14-first edge; 15-second edge; 16-explosion-proof valve; 21-side beam; 211-outer wall; 212-inner wall; 213-supporting groove; 214-reinforcement rib; 215-exhaust hole; 216-liquid inlet pipe; 217-liquid outlet pipe; 218-vent; 22-cross beam; 23-bottom plate; 24-partition beam; 25-exhaust channel; 26-cooling channel; 3-liquid cooling plate.

[0047] F1-first direction; F2-second direction; F21-first misalignment direction; F22-second misalignment direction; F3-third direction. DETAILED DESCRIPTION

[0048] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0049] The components of the embodiments of the present application generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents the selected embodiments of the present application.

[0050] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0051] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0052] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0053] Refer to the following Figures 1 to 11 The present invention describes a battery cell and a battery pack according to some embodiments of the present application.

[0054] See also Figures 1 to 11 As shown, an embodiment of the first aspect of the present application provides a battery cell, which includes a shell and a pole group, wherein a housing cavity for accommodating the pole group is provided in the shell, and the shell includes a first shell portion 11, a curved shell portion 13, and a second shell portion 12 sequentially arranged along a first direction F1, the first shell portion 11 and the second shell portion 12 are parallel to each other, and the first shell portion 11 and the second shell portion 12 are staggered by a predetermined distance along a second direction F2, and the curved shell portion 13 connects the first shell portion 11 and the second shell portion 12. When a plurality of battery cells 1 are stacked along the second direction F2, two adjacent battery cells 1 abut against each other via the curved shell portions 13 to form an expansion gap 10 between two adjacent first shell portions 11 and between two adjacent second shell portions 12.

[0055] According to the monomer provided by the above-mentioned technical features, the first shell and the second shell that are arranged in parallel and staggered in the second direction F2 (i.e., the stacking direction of the battery monomers 1 in the battery pack) are connected by a curved shell, so that when a plurality of battery monomers 1 are stacked along the second direction F2, two adjacent battery monomers 1 abut against each other via each other's curved shell portions 13 to form an expansion gap 10 between the two adjacent first shell portions 11 and between the two adjacent second shell portions 12. In this way, as the battery monomer 1 is used, the volume gradually expands, and the battery pack can use the expansion gap 10 formed between the two adjacent battery monomers 1 to release the expansion force of the battery monomer 1, effectively relieve the expansion pressure of the battery pack case, improve the safety of the battery pack and ensure the sealing of the battery pack.

[0056] like Figures 1 to 12 As shown, F1 shown in the figure may be an example of the first direction F1, and F21 shown in the figure may be an example of the second direction F2, wherein the first direction F1 may intersect with the second direction F2. Figures 1 to 11As shown, the first direction F1 may be perpendicular to the second direction F2, so as to adapt to the structure of most square battery packs. For the convenience of description, the direction intersecting the plane determined by the first direction F1 and the second direction F2 is defined as a third direction F3. The F3 shown in the figure may be an example of the third direction F3. Preferably, as Figures 1 to 11 As shown, the third direction F3 may be perpendicular to a plane defined by both the first direction F1 and the second direction F2 , so as to accommodate the structures of most square battery packs.

[0057] In addition, if Figure 2 As shown, for the convenience of description, in the second direction F2, the misalignment direction of the first shell portion 11 relative to the second shell portion 12 is defined as a first misalignment direction F21, and conversely, the opposite direction of the first misalignment direction F21 is defined as a second misalignment direction F22.

[0058] Preferably, if Figure 1 and Figure 2 As shown, the first shell portion 11, the second shell portion 12 and the curved shell portion 13 are all equal thickness structures in the second direction F2. In other words, the equal thickness structure can be understood as the two end faces of the structure opposite to each other in the second direction F2 being arranged parallel to each other to facilitate the stacking of the battery cells 1 along the second direction F2.

[0059] Preferably, if Figure 1 and Figure 2 As shown, the thicknesses of the first shell portion 11 , the second shell portion 12 and the curved shell portion 13 in the second direction F2 are all equal to ensure the uniform distribution of the battery cells 1 in the first direction F1 .

[0060] Preferably, the thickness of the battery cell 1 in the second direction F2 may be 10 mm to 30 mm.

[0061] Preferably, if Figure 4 As shown, the end surface of the above-mentioned curved shell portion 13 in the first misalignment direction F21 may include a first convex surface 131 and a first concave surface 132 connected to each other, wherein the first convex surface 131 is used to connect the end surface of the first shell portion 11 in the first misalignment direction F21, and the first concave surface 132 is used to connect the end surface of the second shell portion 12 in the first misalignment direction F21, so as to form a smooth transition between the first shell portion 11 and the second shell portion 12 on one side in the first misalignment direction F21.

[0062] Similarly, if Figure 4As shown, the end surface of the above-mentioned curved shell portion 13 in the second misalignment direction F22 may include a second convex surface 133 and a second concave surface 134 connected to each other, wherein the second convex surface 133 is used to connect the end surface of the second shell portion 12 in the second misalignment direction F22, and the second concave surface 134 is used to connect the end surface of the first shell portion 11 in the second misalignment direction F22, so as to form a smooth transition between the first shell portion 11 and the second shell portion 12 on one side in the second misalignment direction F22.

[0063] Preferably, if Figure 3 and Figure 4 As shown, when multiple battery cells 1 are stacked along the second direction F2, two adjacent battery cells 1 abut against each other via the first convex surface 131 of one and the second convex surface 133 of the other (or via the second convex surface 133 of one and the first convex surface 131 of the other) to form an expansion gap 10 between two adjacent first shell portions 11 and between two adjacent second shell portions 12.

[0064] Preferably, if Figure 3 and Figure 4 As shown, the first convex surface 131, the second convex surface 133, the first concave surface 132 and the second concave surface 134 are all partial cylindrical surfaces. Preferably, the central angle corresponding to the partial cylindrical surface can be 120° to 150°, which can not only ensure the smoothness of the surface of the curved shell portion 13, but also ensure the abutment stability of two adjacent battery cells 1 when multiple battery cells 1 are stacked along the second direction F2.

[0065] In an embodiment, further, Figure 2 , Figure 3 and Figure 5 As shown, the first edge portion 14 protrudes a predetermined distance (i.e. Figure 2 L value shown). Correspondingly, Figure 2 , Figure 3 and Figure 6 As shown, the second edge portion 15 protrudes a predetermined distance (i.e. Figure 2 L value shown), so that when multiple battery cells 1 are stacked along the second direction F2, in addition to abutting each other via the bent shell portions 13, two adjacent battery cells 1 can also abut via the first edge portion 14 and the second edge portion 15, thereby increasing the abutment area of ​​the two adjacent battery cells 1 to further increase the stacking stability of the two adjacent battery cells 1.

[0066] Preferably, the predetermined distance may be equal to the final expansion amount of the battery cell 1 to reduce the impact of the expansion of the battery cell 1 on the total volume of the battery module 100. Optionally, the predetermined distance may be 0.5 mm to 2 mm to accommodate the final expansion amount of most battery cells 1.

[0067] Optionally, the size of the battery cell 1 in the first direction F1 may be 300 mm to 12 mm to be suitable for the size of current battery packs.

[0068] In an embodiment, Figure 1 , Figure 3 , Figure 5 and Figure 6 As shown, the battery cell 1 may include a first end and a second end opposite to each other in the third direction F3. The battery cell 1 may also include a first edge portion 14 and a second edge portion 15 both disposed at the first end of the battery cell 1, the first edge portion 14 being disposed at an end of the first shell portion 11 away from the second shell portion 12 in the first direction F1, and the second edge portion 15 being disposed at an end of the second shell portion 12 away from the first shell portion 11 in the first direction F1, so that when the battery cell 1 is loaded into the battery pack case, the battery pack case can achieve the limitation of the battery cell 1 and the case in the third direction F3 by supporting the first edge portion 14 and the second edge portion 15.

[0069] Preferably, although not shown in the figure, the interior of the first edge portion 14 and the interior of the second edge portion 15 may be provided with an exhaust cavity communicating with the accommodation cavity. Figure 3 , Figure 5 and Figure 6 As shown, explosion-proof valves 16 are provided on one side of the first edge 14 and the second edge 15 facing the second end of the battery cell 1, so that the battery cell 1 can achieve thermal runaway exhaust through the part of the battery pack body supporting the first edge 14 and the second edge 15.

[0070] See also Figures 3 to 11 The embodiment of the second aspect of the present application also provides a battery pack, comprising a plurality of battery cells as described in any of the above embodiments, and thus having all the beneficial technical effects of the battery cell 1, which will not be elaborated here.

[0071] Specifically, Figure 3 As shown, the battery pack may include a plurality of the above-mentioned battery cells 1 , and the plurality of battery cells 1 are stacked along the second direction F2 to form a battery module 100 .

[0072] Preferably, the battery pack may further include a box for accommodating the battery module 100 .

[0073] Preferably, if Figures 7 to 11As shown, the box body may include two side beams 21 extending along the second direction F2, the battery module 100 may be arranged between the two side beams 21, and the first edge portion 14 and the second edge portion 15 of each of the battery cells 1 may overlap the two side beams 21 respectively to limit the position of the battery module 100 in the box body.

[0074] Preferably, if Fig. 9 and Fig.10 As shown, an exhaust channel 25 may be provided in the side beam 21 , and the exhaust channels 25 of the two side beams 21 are respectively connected to the explosion-proof valve 16 of the first edge portion 14 and the explosion-proof valve 16 of the second edge portion 15 , so as to facilitate the directional discharge of the gas discharged from the explosion-proof valve 16 through the exhaust channel 25 .

[0075] Preferably, if Fig. 9 and Fig.10 As shown, the side beam 21 may include an inner wall 212 and an outer wall 211 that are opposite to each other and spaced apart in the first direction F1, and the exhaust channel 25 is disposed between the inner wall 212 and the outer wall 211. In this way, the exhaust channel 25 is integrated into the structural space of the side beam 21, thereby effectively saving the space utilization rate of the battery pack. Moreover, compared with the traditional box body in which the exhaust channel 25 is disposed on the bottom plate 23, the exhaust channel 25 is disposed on the side beam 21, and the battery pack is further utilized to realize electrical and thermal separation, thereby improving the safety of the battery pack.

[0076] In an embodiment, Fig. 9 and Fig.10 As shown, a cooling channel 26 extending along the second direction F2 may also be provided in the inner wall 212. At least a portion of the battery module 100 is in contact with the inner wall 212. On the one hand, the heat dissipation efficiency of the battery pack can be effectively improved. On the other hand, the cooling channel 26 is adjacent to the exhaust channel 25. When thermal runaway exhaust occurs in the battery pack, the cooling channel 26 can quickly cool the thermal runaway gas discharged into the exhaust channel 25, thereby further improving the safety of the battery pack.

[0077] Preferably, if Fig. 9 and Fig.10 As shown, a plurality of cooling channels 26 may be disposed in the inner side wall 212 , and the plurality of cooling channels 26 are disposed at intervals along the third direction F3 to increase the distribution area of ​​the cooling channels 26 and improve the cooling efficiency of the side beam 21 .

[0078] Preferably, if Fig. 9 and Fig.10 As shown, the side beam 21 may further include a reinforcing rib 214 connecting the inner side wall 212 and the outer side wall 211 to improve the strength of the side beam 21. Fig. 9 and Fig.10As shown, the reinforcing rib 214 can be disposed between two adjacent cooling channels 26 , which, on the one hand, ensures the stability of the arrangement of the reinforcing rib 214 , and, on the other hand, prevents the cooling channel 26 from being squeezed by the reinforcing rib 214 and deformed.

[0079] Preferably, if Fig.11 As shown, the reinforcing rib 214 may be provided with a vent hole 218 penetrating the reinforcing rib 214 along a third direction F3, so as to facilitate the connection between the two parts of the exhaust channel 25 separated by the reinforcing rib 214, thereby ensuring the effective exhaust space of the exhaust channel 25 and improving the safety of the battery pack.

[0080] Furthermore, if Figure 7 As shown, the box body may further include a bottom plate 23 and a liquid cooling plate 3. The bottom plate 23 is fixed to the bottom of the two side beams 21 to support the battery module 100. The liquid cooling plate 3 may be disposed between the bottom plate 23 and the battery module 100 to further improve the cooling efficiency of the battery pack.

[0081] Preferably, if Figure 7 , Figure 8 and Fig.12 As shown, in the third direction F3, the size of the inner wall 212 is smaller than the size of the outer wall 211, so as to form a supporting groove 213 on the inner side of the side beam 21, and the first edge portion 14 or the second edge portion 15 can be embedded in the supporting groove 213, so that the battery module 100 can be completely wrapped by the side beam 21 to ensure the safety of the battery pack.

[0082] Correspondingly, if Figure 7 , Figure 8 and Fig.12 As shown, the bottom surface of the supporting groove 213 is provided with an exhaust hole 215 connected to the exhaust channel 25 , and the exhaust hole 215 is correspondingly provided with the explosion-proof valve 16 of the first edge portion 14 or the second edge portion 15 to achieve the communication between the exhaust cavity and the exhaust channel 25 .

[0083] Correspondingly, the vent holes 218 and the exhaust holes 215 can be arranged in a one-to-one correspondence to ensure the smooth exhaust of each explosion-proof valve 16 .

[0084] Preferably, if Figure 7 , Figure 8 and Fig.12 As shown, the box body may further include two cross beams 22 extending along the first direction F1, and the two cross beams 22 are respectively connected to the two ends of the two side beams 21 to form a frame surrounding the battery module 100, so as to achieve comprehensive protection of the battery module 100 by the box body.

[0085] Preferably, if Figure 7 , Figure 8 and Fig.12As shown, the box body may further include a partition beam 24 extending along a first direction F1, and the two ends of the partition beam 24 are respectively connected to two side beams 21 to separate the frame body into a first chamber and a second chamber, wherein the battery module 100 may be disposed in the first chamber.

[0086] Optionally, not shown in the figures, the battery pack may further include a control device and a pipe connection device. Both the control device and the pipe connection device may be disposed in the second chamber, which is beneficial to the integration of functional modules of the battery pack and facilitates the installation and maintenance of the battery pack.

[0087] Alternatively, if Figure 8 and Fig.12 As shown, the side beam 21 may also be provided with a liquid inlet pipe 216 and a liquid outlet pipe 217 connected to the cooling channel 26 to achieve liquid cooling circulation in the cooling channel 26 .

[0088] Preferably, if Figure 8 and Fig.12 As shown, the liquid inlet pipe 216 and the liquid outlet pipe 217 can be arranged in the second cavity to facilitate docking with the pipeline connecting device.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell, characterized in that: The invention comprises a shell and a pole group, wherein a housing cavity for accommodating the pole group is arranged in the shell, wherein the shell comprises a first shell portion, a curved shell portion and a second shell portion sequentially arranged along a first direction, wherein the first shell portion and the second shell portion are parallel to each other, and the first shell portion and the second shell portion are staggered by a predetermined distance along a second direction, wherein the curved shell portion connects the first shell portion and the second shell portion, and the second direction intersects with the first direction; When the plurality of battery cells are stacked along the second direction, two adjacent battery cells abut against each other via their bent shell portions, so that an expansion gap is formed between two adjacent first shell portions and between two adjacent second shell portions.

2. The battery cell according to claim 1, characterized in that: The battery cell includes a first end and a second end opposite to each other in a third direction, the third direction intersecting a plane defined by both the first direction and the second direction; The battery cell also includes a first edge portion and a second edge portion, both of which are arranged at a first end of the battery cell, the first edge portion is arranged at an end of the first shell portion in the first direction away from the second shell portion, and the second edge portion is arranged at an end of the second shell portion in the first direction away from the first shell portion.

3. The battery cell according to claim 2, characterized in that: The first edge portion and the second edge portion are both provided with exhaust cavities communicating with the accommodating cavity; An explosion-proof valve is provided on one side of both the first edge portion and the second edge portion facing the second end of the battery cell.

4. The battery cell according to claim 3, characterized in that: It is defined that in the second direction, relative to the second shell portion, the misalignment direction of the first shell portion is a first misalignment direction, and the opposite direction of the first misalignment direction is a second misalignment direction; The first edge portion protrudes by the predetermined distance along the first misalignment direction relative to the end surface of the first shell portion in the first misalignment direction; The second edge portion protrudes by the predetermined distance along the second misaligned direction relative to an end surface of the second shell portion in the second misaligned direction.

5. A battery pack, characterized in that: Comprising a plurality of battery cells as claimed in claim 3 or 4, the plurality of battery cells are stacked along the second direction to form a battery module.

6. The battery pack according to claim 5, characterized in that: It also includes two side beams extending along the second direction, the battery module is arranged between the two side beams, and the first edge portion and the second edge portion of each battery cell are overlapped with the two side beams respectively; An exhaust passage is arranged in the side beam, and the exhaust passages of the two side beams are respectively connected to the explosion-proof valve of the first edge portion and the explosion-proof valve of the second edge portion.

7. The battery pack according to claim 6, characterized in that: The side beam comprises an inner side wall and an outer side wall which are opposite to each other and spaced apart in the first direction, and the exhaust passage is arranged between the inner side wall and the outer side wall; In the third direction, the size of the inner side wall is smaller than that of the outer side wall, so as to form a supporting groove on the inner side of the side beam, and the first edge portion or the second edge portion can be embedded in the supporting groove; An exhaust hole communicating with the exhaust channel is disposed on the bottom surface of the supporting groove, and the exhaust hole is disposed corresponding to the explosion-proof valve of the first edge portion or the second edge portion.

8. The battery pack according to claim 7, characterized in that: The inner side wall is provided with a cooling channel extending along the second direction, the inner side wall is provided with one or more cooling channels, and at least a portion of the battery module is in contact with the inner side wall.

9. The battery pack according to claim 8, characterized in that: When there are multiple cooling channels, the multiple cooling channels are arranged at intervals along the third direction; The side beam further includes a reinforcing rib connecting the inner side wall and the outer side wall; The reinforcing rib is arranged between two adjacent cooling channels; The reinforcing rib is provided with a vent hole penetrating the reinforcing rib along the third direction.

10. The battery pack according to claim 6, characterized in that: Also includes: Two cross beams extending along the first direction, the two cross beams being respectively connected to two ends of the two side beams to form a frame surrounding the battery module; A bottom plate, fixed to the bottom of the frame, for supporting the battery module; The liquid cooling plate is arranged between the bottom plate and the battery module.

Images