Battery cells, batteries and electrical devices

Abstract

The present application discloses a battery cell (10), a battery (1) and an electrical device. The battery cell (10) comprises a housing (11), an electrode assembly (12) and an exhaust bracket (17). The housing (11) comprises a first wall (113). The electrode assembly (12) is accommodated in the housing (11). The exhaust bracket (17) is fixed to a side of the first wall (113) facing the electrode assembly (12) and is used to support the electrode assembly (12) when the battery cell (10) experiences thermal runaway. The exhaust bracket (17) is provided with a first channel (171) extending along a first direction (x), the first direction (x) intersecting with a thickness direction (z) of the first wall (113). Each first channel (171) is provided corresponding to an electrode assembly (12). Based on the above arrangement, the risk of cracking or even explosion of the battery cell (10) can be reduced, and the reliability of the battery cell (10) can be improved.

Description

Technical Field

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

[0002] In some cases, the battery cell includes a housing, an end cap, an electrode assembly, and an insulating member. The end cap is covered on the housing. The electrode assembly and the insulating member are arranged in a space enclosed by the housing and the end cap. The insulating member is arranged between the end cap and the electrode assembly to insulate and isolate the end cap and the electrode assembly.

[0003] However, in the event of thermal runaway of the battery cell, the insulating member may melt, causing the electrode assembly to move toward the end cap and block the exhaust passage, thereby preventing gas from being discharged. Utility Model Content

[0004] The embodiments of the present application provide a battery cell, a battery and an electrical device, which are intended to solve the problem that when a battery cell has thermal runaway, the insulating part may melt, causing the electrode assembly to move toward the end cover and block the exhaust channel, hindering gas discharge.

[0005] The technical solution adopted in the embodiment of the present application is:

[0006] In a first aspect, a battery cell is provided, the battery cell comprising:

[0007] a housing including a first wall;

[0008] an electrode assembly housed in the housing;

[0009] The exhaust bracket is fixed to the side of the first wall facing the electrode assembly and is used to support the electrode assembly in the event of thermal runaway of the battery cell. The exhaust bracket is provided with a first channel extending along a first direction, the first direction intersecting with the thickness direction of the first wall, and each first channel is provided corresponding to an electrode assembly.

[0010] The battery cell provided in the embodiment of the present application can support the electrode assembly through the exhaust bracket fixed to the first wall in the event of thermal runaway, so as to prevent the portion of the electrode assembly supported by the exhaust bracket from moving toward the first wall. Based on this, an exhaust channel flowing along the first direction can be formed between the portion of the electrode assembly supported by the exhaust bracket and the first wall through the first channel of the exhaust bracket, thereby promoting the circulation of the internal space of the battery cell, and promoting the gas generated by the thermal runaway of the electrode assembly to flow to the directional exhaust position of the first wall, especially promoting the gas generated on the side of the electrode assembly to flow to the directional exhaust position of the first wall, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly and the shell, and reducing the risk of cracking of the shell (especially the connection seam of the shell). In addition, each first channel of the exhaust bracket is also respectively arranged corresponding to an electrode assembly, based on which, the first channel can be enabled to discharge the gas generated by the thermal runaway of the electrode assembly corresponding to it in a targeted, timely and rapid manner, thereby optimizing the exhaust effect and exhaust efficiency. As a result, the risk of cracking or even explosion of the battery cells (especially at the welds) can be effectively reduced, and the reliability of the battery cells can be improved.

[0011] In some embodiments, a plurality of electrode assemblies are provided, and each electrode assembly is arranged along a second direction, and the second direction is perpendicular to the first direction;

[0012] The exhaust bracket is provided with two first channels, the two first channels are arranged at intervals along the second direction, and the two first channels are arranged corresponding to two of the electrode assemblies.

[0013] By adopting the above scheme, in the case of thermal runaway of the battery cell, at least two electrode assemblies can be supported by the exhaust bracket to prevent the corresponding parts of the at least two electrode assemblies from moving toward the first wall, so that a larger gap space and exhaust space can be supported between each electrode assembly and the first wall through the exhaust bracket. On this basis, two parallel exhaust channels can be formed between the two electrode assemblies and the first wall through the two first channels of the exhaust bracket spaced along the second direction and penetrating along the first direction. Based on this, it is convenient for the exhaust bracket to focus on, timely and quickly exhaust the gas generated by the thermal runaway of at least two electrode assemblies through the two first channels, so that the exhaust area of ​​the exhaust bracket can be optimized on the basis of taking into account the structural strength and support strength of the exhaust bracket, and the exhaust effect and exhaust efficiency can be optimized, so that the directional and rapid exhaust of the gas can be promoted, the risk of gas accumulation in the small space enclosed by the side of the electrode assembly and the shell can be reduced, the risk of cracking or even explosion of the battery cell (especially at the weld) can be reduced, and the reliability of the battery cell can be improved.

[0014] In some embodiments, the two first channels of the exhaust bracket are symmetrically distributed about a center line of the first wall along the second direction.

[0015] By adopting the above scheme, by making the two first channels of the exhaust bracket symmetrically distributed about the center line of the first wall along the second direction, when the battery cell has thermal runaway, the two first channels of the exhaust bracket can be made to discharge the gas generated by the thermal runaway of the central electrode assembly in a focused, timely and rapid manner. Based on this, the exhaust effect and exhaust efficiency of the exhaust bracket on the middle area of ​​each electrode assembly can be optimized, which can promote the directional and rapid discharge of gas, reduce the risk of gas accumulation in the small space enclosed by the side of the electrode assembly and the shell, reduce the risk of cracking or even explosion of the battery cell (especially the middle area of ​​the connection seam of the shell), and improve the reliability of the battery cell.

[0016] Furthermore, by symmetrically distributing the two first channels of the exhaust bracket about the center line of the first wall along the second direction, the layout of the first channels of the exhaust bracket can be balanced and optimized. Based on this, in the case of thermal runaway of the battery cell, the exhaust bracket can provide a balanced exhaust effect through the two first channels on the opposite sides of the center line of the first wall along the second direction, thereby optimizing the exhaust effect and exhaust efficiency, reducing the risk of gas accumulation on one side, reducing the risk of cracking or even explosion of the battery cell, and improving the reliability of the battery cell.

[0017] In some embodiments, a plurality of exhaust brackets are provided.

[0018] By adopting the above scheme, multiple exhaust brackets can be set up so that when thermal runaway occurs in the battery cell, the electrode assembly can be supported together by the multiple exhaust brackets. Based on this, the supporting effect of each exhaust bracket on the electrode assembly can be enhanced, the supporting pressure of each exhaust bracket can be dispersed and uniform, and each exhaust bracket can support a stable and larger gap space and exhaust space between each electrode assembly and the first wall, thereby promoting the connectivity of the internal space of the battery cell, promoting the directional and rapid discharge of gas, and reducing the risk of cracking or even explosion of the battery cell (especially at the weld).

[0019] In some embodiments, at least two exhaust brackets are spaced apart from each other along the first direction.

[0020] By adopting the above scheme, by arranging at least two exhaust brackets at intervals along the first direction, it is convenient for these exhaust brackets to support the same part of the electrode assembly together. Based on this, it is convenient to support a stable gap space and exhaust space between the same part of the electrode assembly and the first wall through these exhaust brackets in the case of thermal runaway of the battery cell, and reduce the risk of the exhaust channel being disconnected and partially blocked due to the partial abutment of the electrode assembly to the first wall. Thereby, the internal space of the battery cell can be stably and reliably connected, the directional and rapid exhaust of gas can be promoted, and the risk of cracking or even explosion of the battery cell (especially at the weld) can be reduced.

[0021] In some embodiments, at least two exhaust brackets are disposed at opposite ends of the first wall along the first direction.

[0022] By adopting the above scheme, by arranging at least two exhaust brackets at opposite ends of the first wall along the first direction, the supporting effect of the exhaust bracket at the end of the first wall along the first direction can be optimized, the spatial connectivity between the end and the middle of the first wall along the first direction can be promoted, and the gas can be directed to flow from the end to the middle of the first wall along the first direction. Based on this, the internal space of the battery cell can be reliably connected, especially the space between the end and the middle of the first wall along the first direction can be connected, so as to promote the directional and rapid discharge of gas, reduce the risk of gas accumulation in the small space enclosed by the side of the electrode assembly and the shell, and reduce the risk of cracking or even explosion of the battery cell (especially at the weld).

[0023] In some embodiments, the battery cell further includes an insulating member, which is disposed on a side of the first wall facing the electrode assembly and insulates and isolates the first wall and the electrode assembly. A receiving cavity is disposed on a side of the insulating member facing the first wall, and the exhaust bracket is received in the receiving cavity.

[0024] By adopting the above scheme, during the normal use of the battery cell and in the early stage of thermal runaway of the battery cell, the first wall and the electrode assembly can be insulated and isolated by an unmelted insulating member arranged on the side of the first wall facing the electrode assembly, so as to reduce the risk of short circuit, current leakage and the like. In addition, a receiving cavity can be provided by the insulating member to accommodate the exhaust bracket, so that the exhaust bracket can share space with the insulating member in the thickness direction of the first wall, thereby reducing the additional space occupied by the exhaust bracket in the thickness direction of the first wall, and improving the space utilization and energy density of the battery cell. In addition, the strength of the corresponding area of ​​the insulating member can be correspondingly enhanced by the exhaust bracket to enhance the supporting effect of the corresponding area of ​​the insulating member on the electrode assembly, thereby stabilizing the position and structure of the electrode assembly, reducing the relative movement or shaking of the electrode assembly, and reducing the risk of loosening or deformation of the electrode assembly.

[0025] By adopting the above scheme, when a battery cell undergoes thermal runaway and the insulating member melts because the thermal runaway temperature of the battery cell exceeds its melting point, the electrode assembly can be supported by the exhaust bracket exposed to the insulating member to prevent the portion of the electrode assembly supported by the exhaust bracket from moving toward the first wall, thereby creating a gap space and an exhaust space between the electrode assembly and the first wall, and facilitating the connection of the internal space of the battery cell through the first channel of the exhaust bracket, thereby promoting the directional and rapid discharge of gas and reducing the risk of cracking or even explosion of the battery cell (especially at the weld).

[0026] In some embodiments, the insulating member includes a main body and a plurality of bosses, the plurality of bosses are arranged at intervals along the first direction, the main body is connected to the bosses and to the first wall; the accommodating cavity is provided in the bosses.

[0027] By adopting the above solution, the insulating member can reliably insulate and isolate the first wall and the electrode assembly by being connected to the main body on the side of the first wall facing the electrode assembly, thereby reducing the risk of short circuit, current leakage, etc. The insulating member can also abut the electrode assembly by being connected to the boss on the side of the main body facing the electrode assembly to fill the gap between the electrode assembly and the first wall, thereby tightly fixing the electrode assembly, thereby reducing the relative movement or shaking of the electrode assembly, stabilizing the position and structure of the electrode assembly, and reducing the risk of loosening or deformation of the electrode assembly.

[0028] By adopting the above scheme, since the thickness of the insulating part at the position corresponding to the boss is relatively large, by setting a receiving cavity at the position corresponding to the boss of the insulating part, it is easy to process the receiving cavity, and it is also easy to process a larger-sized receiving cavity to accommodate the exhaust bracket. Based on this, on the one hand, the processing convenience of the receiving cavity can be improved, and the impact of the processing of the receiving cavity on the structural strength of the insulating part can be reduced, stress concentration can be reduced, and the risk of damage to the insulating part can be reduced, thereby maintaining the insulation isolation and other functions of the insulating part, and improving the performance and service life of the insulating part. On the other hand, the receiving cavity can accommodate more parts of the exhaust bracket, and the exhaust bracket can share as much space as possible with the insulating part in the thickness direction of the first wall, thereby reducing the additional space occupied by the exhaust bracket in the thickness direction of the first wall, and improving the space utilization and energy density of the battery cell.

[0029] In some embodiments, the cross-sectional area of ​​the first channel of the exhaust bracket is S1, the area of ​​the side surface of the corresponding boss along the first direction is S2, the capacity of the battery cell is C, and the mass percentage of nickel in the positive electrode active material contained in the battery cell is N;

[0030] 0.125*(C / 40)*N≤S1≤0.25*S2.

[0031] By adopting the above scheme, according to the capacity C of the battery cell and the mass percentage N of nickel in the positive electrode active material in the battery cell, by making the cross-sectional area S1 of a first channel greater than or equal to 0.125*(C / 40)*N, the exhaust bracket can provide sufficient exhaust area through the first channel with sufficient cross-sectional area in the event of thermal runaway of the battery cell, thereby optimizing the exhaust effect and exhaust efficiency and reducing the risk of cracking or even explosion of the battery cell (especially at the weld).

[0032] On this basis, according to the area S2 of the side surface along the first direction of the corresponding boss accommodating the exhaust bracket, the cross-sectional area S1 of the first channel can be made less than or equal to 0.25*S2 to coordinate the sizes of the first channel and the exhaust bracket so that the exhaust bracket can be accommodated in the accommodating cavity opened by the insulating member, thereby allowing the exhaust bracket to share as much space as possible with the insulating member, thereby improving the space utilization and energy density of the battery cell.

[0033] In some embodiments, the insulating member has a first end surface along the first direction, the first end surface is provided with at least one second channel, and the second channel is connected to the side surface of the insulating member facing the first wall.

[0034] By adopting the above scheme, when a battery cell undergoes thermal runaway and the insulating member does not melt because the thermal runaway temperature of the battery cell does not exceed its melting point, the second channel provided on the first end face of the insulating member can promote the circulation of the internal space of the battery cell, and can enable the gas generated by the thermal runaway of the electrode assembly to flow to the directional exhaust position of the first wall, especially the gas generated on the side of the electrode assembly to flow to the directional exhaust position of the first wall through the second channel, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly and the outer shell, and reducing the risk of cracking of the outer shell (especially the connecting seam of the outer shell).

[0035] In some embodiments, the total occupied area of ​​each second channel on the first end surface is S3, the area of ​​the first end surface is S4, the capacity of the battery cell is C, and the mass percentage of nickel in the positive electrode active material contained in the battery cell is N;

[0036] 0.125*(C / 10)*N≤S3≤0.5*S4.

[0037] By adopting the above scheme, according to the capacity C of the battery cell and the mass percentage N of nickel in the positive electrode active material in the battery cell, by making the total occupied area S3 of the second channels on the first end face greater than or equal to 0.125*(C / 10)*N, when thermal runaway occurs in the battery cell and the insulating member does not melt because the thermal runaway temperature of the battery cell does not exceed its melting point, the insulating member can provide sufficient exhaust area through the second channels, thereby optimizing the exhaust effect and exhaust efficiency and reducing the risk of cracking or even explosion of the battery cell (especially at the weld).

[0038] On this basis, according to the area S4 of the first end face, the total occupied area S3 of the second channels on the first end face can be made less than or equal to 0.5*S4 to coordinate the area ratio of each second channel on the first end face, so that the total occupied area of ​​each second channel on the first end face is not too large, thereby reducing the impact of the setting of each second channel on the structural strength of the insulating part (especially the boss), reducing stress concentration, reducing the risk of damage to the insulating part, thereby maintaining the insulation isolation and other functions of the insulating part, and improving the performance and service life of the insulating part.

[0039] In some embodiments, the melting point of the exhaust bracket is greater than the melting point of the insulation.

[0040] By adopting the above scheme, by making the melting point of the exhaust bracket greater than the melting point of the insulating member, the exhaust bracket can be made difficult for the insulating member to melt. Based on this, when the battery cell undergoes thermal runaway and the insulating member melts because the thermal runaway temperature of the battery cell exceeds its melting point, the exhaust bracket can be exposed to the insulating member and support the electrode assembly in a difficult-to-melt, unmelted form to prevent the portion of the electrode assembly supported by the exhaust bracket from moving toward the first wall, thereby supporting a gap space and an exhaust space between the electrode assembly and the first wall, and facilitating the connection of the internal space of the battery cell through the first channel of the exhaust bracket, thereby promoting the directional and rapid discharge of gas, and reducing the risk of cracking or even explosion of the battery cell (especially at the weld).

[0041] In some embodiments, the exhaust bracket is a metal piece.

[0042] By adopting the above solution, by making the exhaust bracket a metal part, on the one hand, it is easy to process and connect the exhaust bracket, especially to conveniently, quickly and firmly fix the exhaust bracket to the first wall by welding. On the other hand, the exhaust bracket can have a higher structural strength and melting point, and can maintain a stable shape and reliably support the electrode assembly in the event of thermal runaway of the battery cell.

[0043] In some embodiments, the exhaust bracket is a non-metallic part.

[0044] By adopting the above solution, the exhaust bracket is made of non-metallic parts, which can reduce the weight of the exhaust bracket and reduce the cost of the exhaust bracket. It is also convenient for the processing, forming and connection and fixing of the exhaust bracket. For example, the exhaust bracket can be fixed to the first wall by bonding or other methods.

[0045] In some embodiments, the exhaust bracket includes a connecting portion and at least one supporting portion, the connecting portion is connected to the first wall, and the supporting portion is connected to a side of the connecting portion facing away from the first wall.

[0046] By adopting the above solution, the exhaust bracket can be reliably fixed to the first wall through the connecting portion. Based on this, the installation position and installation state of the exhaust bracket can be fixed relative to the first wall. In this way, in the case of thermal runaway of the battery cell, even under the action of air pressure impact force or other forces, the exhaust bracket can stabilize its installation position and installation state, thereby enabling the exhaust bracket to reliably function, reducing the risk of the exhaust bracket damaging the diaphragm of the electrode assembly due to displacement, and reducing the risk of the exhaust bracket damaging the diaphragm of the electrode assembly and causing new short circuits, overheating, smoke, fire, etc.

[0047] On this basis, the exhaust bracket can also reliably support the electrode assembly by connecting to the support portion on the side of the connecting portion away from the first wall in the event of thermal runaway of the battery cell. Based on this, the exhaust bracket can support the gap space and exhaust space between the electrode assembly and the first wall, and the exhaust bracket can promote the connection of the internal space of the battery cell through the first channel, thereby optimizing the structure, utility and performance of the exhaust bracket.

[0048] In some embodiments, two supporting portions are provided, and the two supporting portions are provided at opposite ends of the connecting portion, and each supporting portion and the connecting portion enclose a first channel.

[0049] By adopting the above solution, the exhaust bracket can optimize its structure and supporting effect through the two supporting parts disposed at the opposite ends of the connecting part. Based on this, in the case of thermal runaway of the battery cell, the exhaust bracket can support the electrode assembly in a balanced and stable manner through the two supporting parts, so that the exhaust bracket can support a stable and large gap space and exhaust space between the electrode assembly and the first wall.

[0050] On this basis, the exhaust bracket can also form two parallel exhaust channels through the two first channels formed by the two supporting parts to optimize the exhaust area of ​​the exhaust bracket, optimize the exhaust effect and exhaust efficiency, thereby promoting the directional and rapid discharge of gas, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly and the outer shell, reducing the risk of cracking or even explosion of the battery cell (especially at the weld), and improving the reliability of the battery cell.

[0051] In some embodiments, the supporting portion includes a first supporting wall and a second supporting wall, the first supporting wall is vertically connected to the connecting portion, and the second supporting wall is bent and connected to an end of the first supporting wall away from the connecting portion.

[0052] By adopting the above solution, the support part can enhance its own structural strength by setting the first support wall and the second support wall, so that the support part can reliably play a supporting role. Based on this, in the case of thermal runaway of the battery cell, the support part of the exhaust bracket can be supported between the connecting part and the second support wall through the first support wall, and abut against the electrode assembly through the second support wall, so as to reliably support the electrode assembly. In this way, the structure of the exhaust bracket can be optimized, so that the exhaust bracket can support a stable and large gap space and exhaust space between the electrode assembly and the first wall.

[0053] Furthermore, according to the angle between the first support wall and the second support wall, as well as the size design of the first support wall and the size design of the second support wall, the cross-sectional area of ​​the first channel enclosed by the support portion and the connecting portion can be adjusted, thereby optimizing the exhaust area of ​​the exhaust bracket, and optimizing the exhaust effect and exhaust efficiency.

[0054] In some embodiments, one end of each second supporting wall away from the first supporting wall is spaced apart from another second supporting wall.

[0055] By adopting the above scheme, the two second support walls of the exhaust bracket can be spaced apart from each other. Based on this, on the one hand, it is convenient for operators to flexibly and conveniently perform the connection (such as welding) operation between the exhaust bracket and the first wall through the space between the two second support walls, thereby improving the connection convenience of the exhaust bracket. On the other hand, the processing of the two support parts can be made independent of each other, which can facilitate the processing and forming of the exhaust bracket by means of pier forming, thereby improving the convenience of processing and forming of the exhaust bracket.

[0056] On the other hand, the two second support walls can be made to move independently of each other. Based on this, when the support portion supports the electrode assembly, the second support wall can be bent relative to the first support wall toward the connecting portion under the action of impact force or other external force, so that the second support wall, the first support wall and the connecting portion can form a triangular stable structure. In this way, the structure and supporting effect of the exhaust bracket can be optimized, the exhaust bracket can be made to support the exhaust space between the electrode assembly and the first wall permanently and reliably, the exhaust bracket can be made to provide a first channel between the electrode assembly and the first wall for the circulation of gas, and the risk of the exhaust bracket being crushed by impact force or other external force and blocking the exhaust channel can be reduced, thereby improving the performance and service life of the exhaust bracket, and optimizing the exhaust effect and exhaust efficiency.

[0057] In some embodiments, one end of each second supporting wall away from the first supporting wall is connected to another second supporting wall via a weak portion.

[0058] By adopting the above solution, the ends of the two second support walls of the exhaust bracket that are close to each other can be connected via the weak portion. Based on this, in the early stage of the exhaust bracket supporting the electrode assembly, the exhaust bracket can support the electrode assembly together by supporting each other via the two connected second support walls, thereby optimizing the supporting effect of the exhaust bracket on the electrode assembly.

[0059] In the later stage when the exhaust bracket supports the electrode assembly, the second support wall can be bent toward the connecting part relative to the first support wall to which it is connected under the action of impact force or other external force, so that the second support wall, the first support wall and the connecting part can form a triangular stable structure, and the two second support walls can be arranged at an angle along the weak part. In this way, the structure and supporting effect of the exhaust bracket can be optimized, the exhaust bracket can be supported to form an exhaust space between the electrode assembly and the first wall in a long-term and reliable manner, the exhaust bracket can be provided with a first channel for gas circulation between the electrode assembly and the first wall in a long-term manner, and the risk of the exhaust bracket being crushed by impact force or other external force and blocking the exhaust channel can be reduced, thereby improving the performance and service life of the exhaust bracket, and optimizing the exhaust effect and exhaust efficiency.

[0060] In some embodiments, the exhaust bracket is welded to the first wall.

[0061] By adopting the above solution, by welding the exhaust bracket to the first wall, the connection convenience, connection strength, connection firmness and durability between the exhaust bracket and the first wall can be improved, and the risk of loosening or detachment between the exhaust bracket and the first wall can be reduced.

[0062] In some embodiments, the exhaust bracket is made of the same material as the first wall.

[0063] By adopting the above solution, by making the material of the exhaust bracket the same as that of the first wall, welding of the exhaust bracket and the first wall can be facilitated, which can help improve the connection convenience and connection strength between the exhaust bracket and the first wall.

[0064] In a second aspect, a battery is provided, the battery comprising the battery cell provided in the embodiment of the present application.

[0065] By adopting the above solution, the battery can reduce the risk of battery explosion by applying the battery cells provided in the embodiments of the present application, thereby improving the reliability and service life of the battery.

[0066] In a third aspect, an electrical device is provided, which includes the battery provided in an embodiment of the present application, or the battery cell provided in an embodiment of the present application.

[0067] By adopting the above solution, the electrical device can improve the reliability and service life of the electrical device by applying the battery or battery cell provided in the embodiment of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] In order to clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments of the present application or the exemplary technical description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0069] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0070] Figure 2 An exploded schematic diagram of a battery provided in some embodiments of the present application;

[0071] Figure 3 An exploded schematic diagram of a battery cell provided in some embodiments of the present application;

[0072] Figure 4 for Figure 3 An exploded schematic diagram of a partial structure of a battery cell is provided;

[0073] Figure 5 A front view of a battery cell provided for some embodiments of the present application;

[0074] Figure 6 for Figure 5 A cross-sectional view along AA is provided;

[0075] Figure 7 A schematic diagram of the structure of a first wall, an adapter, an explosion-proof valve and an exhaust bracket provided in some embodiments of the present application;

[0076] Figure 8 A front view of an exhaust bracket provided for some embodiments of the present application, wherein an end of each second support wall away from the first support wall is spaced apart from another second support wall;

[0077] Fig. 9 for Figure 8 A schematic diagram of a deformed form of an exhaust bracket is provided;

[0078] Fig.10 A front view of an exhaust bracket provided for some other embodiments of the present application, wherein one end of each second support wall away from the first support wall is connected to another second support wall through a weak portion;

[0079] Fig.11 for Fig.10 Schematic diagrams of deformed forms of exhaust brackets are provided.

[0080] Among them, the reference numerals in the figure are:

[0081] 1-battery, 2-controller, 3-motor; 100-battery unit, 200-box, 201-first part, 202-second part;

[0082] 10-battery cell, 11-housing, 111-shell, 112-end cover, 113-first wall, L-center line of the first wall along the second direction; 12-electrode assembly, 121-electrode body, 122-ear, 122a-positive electrode ear, 122b-negative electrode ear; 13-insulating member, 131-body, 132-boss, 133-opening, 134-accommodating cavity, 135-first end surface, 136-second channel; 14-electrode terminal, 14a-positive electrode terminal, 14b-negative electrode terminal; 15-adapter, 15a-positive electrode adaptor, 15b-negative electrode adaptor; 16-explosion-proof valve; 17-exhaust bracket, 171-first channel, 172-connecting part, 173-supporting part, 1731-first supporting wall, 1732-second supporting wall, 174-weak part; x-first direction, z-thickness direction of the first wall, y-second direction. DETAILED DESCRIPTION

[0083] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clear and understandable, the application is described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain this application and are not used to limit this application.

[0084] In the description of the present application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0085] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0086] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 this application can be understood according to specific circumstances.

[0087] A battery cell is the smallest unit for storing and outputting electrical energy. In some cases, a battery cell includes a shell, an end cap, an electrode assembly, and an insulating member. The end cap is fitted to the shell. The end cap and the shell are components that cooperate with each other to form the internal environment of the battery cell. The space enclosed by the shell and the end cap is isolated from the external environment and can be used to accommodate components such as the electrode assembly and the insulating member. The electrode assembly is arranged in the space enclosed by the shell and the end cap, and the electrode assembly is the component in the battery cell where the electrochemical reaction occurs. The insulating member is arranged in the space enclosed by the shell and the end cap, and in particular, between the end cap and the electrode assembly. The insulating member is a component used to insulate and isolate the end cap and the electrode assembly.

[0088] Thermal runaway may occur in battery cells under the influence of factors such as overheating, overcharging or external damage. In the event of thermal runaway of a battery cell, gas will be generated inside the battery cell. The gas will be discharged in the direction close to the end cap, and the strong air pressure will cause the electrode assembly to move in the direction close to the end cap. In addition, as the thermal runaway temperature of the battery cell increases, the insulating member may melt, causing the electrode assembly to move in the direction close to the end cap and abut against the end cap under the impact of the air pressure, causing the exhaust channel between the electrode assembly and the end cap to be blocked and closed, thereby hindering the discharge of gas, especially the discharge of gas generated on the side of the electrode assembly. In this way, part of the gas will accumulate on the side of the electrode assembly, between the end cap and the shell. As the gas accumulates and the air pressure increases, the battery cell, especially the connection between the end cap and the shell, is prone to cracking and even explosion.

[0089] Therefore, the embodiment of the present application provides a battery cell, which can support the electrode assembly through the exhaust bracket fixed to the first wall in the event of thermal runaway, so as to prevent the portion of the electrode assembly supported by the exhaust bracket from moving toward the first wall. Based on this, an exhaust channel flowing along the first direction can be formed between the portion of the electrode assembly supported by the exhaust bracket and the first wall through the first channel of the exhaust bracket, thereby promoting the circulation of the internal space of the battery cell, and promoting the gas generated by the thermal runaway of the electrode assembly to flow to the directional exhaust position of the first wall, especially promoting the gas generated on the side of the electrode assembly to flow to the directional exhaust position of the first wall, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly and the shell, and reducing the risk of cracking of the shell (especially the connection seam of the shell). In addition, each first channel of the exhaust bracket is also respectively arranged corresponding to an electrode assembly, based on which, the first channel can be enabled to discharge the gas generated by the thermal runaway of the electrode assembly corresponding to it in a targeted, timely and rapid manner, thereby optimizing the exhaust effect and exhaust efficiency. As a result, the risk of cracking or even explosion of the battery cells (especially at the welds) can be effectively reduced, and the reliability of the battery cells can be improved.

[0090] The battery cell disclosed in the embodiment of the present application can be a lithium-ion secondary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery or a magnesium-ion battery, etc. The battery cell can be cylindrical, flat, rectangular or other shapes, etc. The battery cell can be packaged in different ways to form a cylindrical battery cell, a square battery cell or a soft-pack battery cell, etc.

[0091] The battery cells disclosed in the embodiments of the present application can be used independently or in combination with other battery cells to form a modular battery that can provide high voltage and capacity, such as a battery module, a battery module or a battery pack.

[0092] The battery cells and batteries disclosed in the embodiments of the present application can be used in electrical devices that use battery cells and batteries as power sources, or in various energy storage systems that use battery cells and batteries as energy storage elements. The electrical device may be, but is not limited to, a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, and the like. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, and the like.

[0093] In order to illustrate the technical solution provided by the present application, the following is a detailed description with reference to specific drawings and embodiments, and taking "the electrical device being a vehicle" as an example.

[0094] See also Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application. The vehicle may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 1 is provided inside the vehicle, and the battery 1 may be provided at the bottom, head or tail of the vehicle. The battery 1 is used to power the vehicle, for example, the battery 1 can be used as an operating power source for the vehicle. The vehicle may also include a controller 2 and a motor 3, and the controller 2 is used to control the battery 1 to power the motor 3, for example, for starting, navigating and driving the vehicle. Working power requirements.

[0095] In some embodiments of the present application, the battery 1 can be used not only as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0096] See also Figure 2 , Figure 2 The exploded schematic diagram of the battery 1 provided in some embodiments of the present application. The battery 1 comprises a battery cell 100 and a box body 200 , wherein the battery cell 100 is accommodated in the box body 200 .

[0097] The box body 200 is used to provide a storage space for components such as the battery cell 100. The box body 200 can provide dustproof, waterproof and protective protection for the battery cell 100 and other components contained therein, and can reduce the impact of external liquids or other foreign matter on the effectiveness and performance of the battery cell 100 and other components, and can effectively extend the service life of the battery 1.

[0098] Among them, the box body 200 can adopt a variety of structures. In some embodiments, the box body 200 may include a first part 201 and a second part 202, the first part 201 and the second part 202 cover each other, and the first part 201 and the second part 202 jointly define a storage space for accommodating the battery unit 100. The second part 202 may be a hollow structure with one end open, and the first part 201 may be a plate-like structure, and the first part 201 covers the open side of the second part 202, so that the first part 201 and the second part 202 jointly define a storage space; the first part 201 and the second part 202 may also be hollow structures with one side open, and the open side of the first part 201 covers the open side of the second part 202.

[0099] The box body 200 may be in various shapes, such as a cylinder, a cuboid, etc.

[0100] The box body 200 may be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0101] The battery cell 100 is an energy storage unit that can convert chemical energy into electrical energy. In the battery 1, one battery cell 100 can be provided, or at least two battery cells 100 can be provided. In the case where at least two battery cells 100 are provided, the at least two battery cells 100 can be connected in series, in parallel, or in mixed connection. Mixed connection means that at least two battery cells 100 are connected in series and in parallel.

[0102] The battery unit 100 may be a battery cell 10 (eg Figure 3 As shown). At least two battery cells 10 can be directly connected in series, in parallel or in mixed connection, and then the whole formed by at least two battery cells 10 is accommodated in the box body 200. Among them, the battery cell 10 can be a lithium-ion secondary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery or a magnesium-ion battery, etc. The battery cell 10 can be cylindrical, flat, rectangular or other shapes, etc. The battery cell 10 can be packaged in different ways to form a cylindrical battery cell, a square battery cell or a soft-pack battery cell, etc.

[0103] Alternatively, the battery unit 100 may be a battery module or a battery module. At least two battery cells 10 may be connected in series, in parallel, or in a hybrid connection to form a modular structure, i.e., a battery module or a battery module; at least two battery modules or battery modules may then be connected in series, in parallel, or in a hybrid connection to form a whole, and accommodated in the box 200.

[0104] Of course, the battery 1 may also include other structures, for example, the battery 1 may also include a busbar component (not shown in the figure) for realizing electrical connection between at least two battery cells 100. For another example, the battery 1 may also include a power distribution device (not shown in the figure) for serving as a control unit for distributing energy of the battery 1 and distributing high voltage to the battery 1.

[0105] Of course, in some embodiments, the battery 1 may not include the box body 200, but at least two battery cells 10 are electrically connected and formed into a whole through necessary fixing structures and then assembled into an electrical device.

[0106] See also Figure 3 , Figure 3 The exploded schematic diagram of the battery cell 10 provided in some embodiments of the present application. The battery cell 10 is the smallest unit for storing and outputting electric energy. The battery cell 10 includes a housing 11, an electrode assembly 12, an insulating member 13, an electrode terminal 14, an adapter 15, an explosion-proof valve 16, an electrolyte (not shown in the figure), and other components.

[0107] The outer shell 11 is a component that isolates the internal environment of the battery cell 10 from the external environment. The outer shell 11 may include a shell 111 and an end cover 112. The end cover 112 is a component that covers the opening of the shell 111 to isolate the internal environment of the battery cell 10 from the external environment. In some embodiments, the shape of the end cover 112 can be adapted to the shape of the shell 111 to match the shell 111. In some embodiments, the end cover 112 can be made of a material with a certain hardness and strength, so that the end cover 112 is not easily deformed when squeezed and collided, so that the battery cell 10 can have a higher structural strength and the reliability performance can also be improved. Among them, the material of the end cover 112 can be diversified, and the end cover 112 can be made of copper, iron, aluminum, stainless steel, aluminum alloy, plastic and other materials.

[0108] The shell 111 is a component used to cooperate with the end cap 112 to form the internal environment of the battery cell 10. The internal environment formed by the shell 111 and the end cap 112 can be used to accommodate the electrode assembly 12, the insulating member 13, the electrolyte and other components. In some embodiments, the shell 111 and the end cap 112 can be independent components, and an opening can be set on the shell 111, and the end cap 112 is made to cover the opening at the opening to form the internal environment of the battery cell 10. In some embodiments, the end cap 112 and the shell 111 can also be integrated. Specifically, the end cap 112 and the shell 111 can form a common connection surface before other components are put into the shell. When it is necessary to encapsulate the interior of the shell 111, the end cap 112 is made to cover the shell 111. Among them, the shell 111 can be of various shapes and sizes, such as a cuboid, a cylinder, a hexagonal prism, etc. The shape of the shell 111 can be determined according to the shape and size of the electrode assembly 12. The material of the housing 111 can be varied, and the housing 111 can be made of copper, iron, aluminum, stainless steel, aluminum alloy, plastic, and other materials.

[0109] The electrode assembly 12 is a component in the battery cell 10 where an electrochemical reaction occurs. The housing 11 may include one or at least two electrode assemblies 12. The electrode assembly 12 includes a positive electrode sheet (not shown in the figure), a negative electrode sheet (not shown in the figure) and a separator (not shown in the figure), which separates the positive electrode sheet from the negative electrode sheet. The positive electrode sheet, the separator and the negative electrode sheet can be processed by winding, stacking or other methods to form the electrode assembly 12. In the electrode assembly 12, the parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the electrode body 121 of the electrode assembly 12, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute a pole ear 122, which is the current transmission end of the electrode assembly 12 for transmitting current. The tab 122 of the positive electrode sheet is the positive electrode tab 122a, and the tab 122 of the negative electrode sheet is the negative electrode tab 122b. The positive electrode tab 122a and the negative electrode tab 122b can be located together at one end of the electrode body 121 or respectively at both ends of the electrode body 121.

[0110] The electrolyte is the liquid that soaks the electrode assembly 12. The battery cell 10 mainly relies on the movement of active ions between the positive electrode plate and the negative electrode plate to work. When the battery cell 10 is charged, the positive electrode plate will generate active ions, and the active ions provided by the positive electrode plate can penetrate the pores of the diaphragm, move to the negative electrode plate via the electrolyte, and embed into the negative active material of the negative electrode plate. Conversely, when the battery cell 10 is discharged, the active ions embedded in the negative active material of the negative electrode plate escape, and the active ions escaped from the negative electrode plate can penetrate the pores of the diaphragm, move to the positive electrode plate via the electrolyte, and embed into the positive active material of the positive electrode plate. Among them, the active ions can be lithium ions, sodium ions, and the like.

[0111] The electrode terminal 14 is a component electrically connected to the electrode assembly 12 and used to output or input electrical energy. The electrode terminal 14 includes a positive electrode terminal 14a and a negative electrode terminal 14b. The positive electrode terminal 14a is electrically connected to the positive electrode tab 122a of the electrode assembly 12. The negative electrode terminal 14b is electrically connected to the negative electrode tab 122b of the electrode assembly 12. The electrode terminal 14 can be installed in the housing 11 and stabilize the installation position and installation state relative to the housing 11. In some embodiments, the electrode terminal 14 can be installed in the housing 11 by flanging and riveting.

[0112] The adapter 15 is a current collecting member electrically connected between the tab 122 of the electrode assembly 12 and the corresponding electrode terminal 14. The adapter 15 may also be referred to as an adapter connector, a current collecting plate or an adapter sheet, etc. The adapter 15 has a conductive property and is made of a conductive material. The material of the adapter 15 may include aluminum, aluminum alloy, copper, copper alloy, copper-aluminum alloy, etc. The adapter 15 includes a positive electrode adapter 15a and a negative electrode adapter 15b. The positive tab 122a of the electrode assembly 12 may be electrically connected to the positive electrode terminal 14a through the positive electrode adapter 15a, and the negative tab 122b of the electrode assembly 12 may be electrically connected to the negative electrode terminal 14b through the negative electrode adapter 15b to form a current loop. In some embodiments, the adapter 15 may be connected to the tab 122 of the electrode assembly 12 by welding, abutment, etc. The adapter 15 may be connected to the electrode terminal 14 by welding, abutment, etc. The shape of the adapter 15 can be various, such as square, round, special-shaped, etc.

[0113] The insulating member 13 is a component with insulating properties. The insulating member 13 is arranged in the outer shell 11, especially between the electrode assembly 12 and the wall portion of the outer shell 11 having the electrode terminal 14 (such as the end cover 112). On the basis that the pole ear 122 of the electrode assembly 12 and the corresponding electrode terminal 14 can be electrically connected, the insulating member 13 can be used to insulate and isolate the electrode assembly 12 and the wall portion of the outer shell 11 having the electrode terminal 14 to reduce the risk of short circuit, current leakage and the like. In addition, the insulating member 13 can also be fixed to the wall portion of the outer shell 11 having the electrode terminal 14, and abut the electrode assembly 12 to fill the gap between the electrode assembly 12 and the wall portion of the outer shell 11, and tightly fix the electrode assembly 12, so that the electrode assembly 12 will not move or shake relatively during the use of the battery cell 10, which is conducive to maintaining the structural integrity of the battery cell 10 and reducing the risk of loosening or deformation of the electrode assembly 12.

[0114] In some embodiments, an explosion-proof valve 16 may also be provided on the housing 11, and the explosion-proof valve 16 may be used to release the internal pressure when the internal pressure (or temperature) of the battery cell 10 reaches a threshold value. Correspondingly, an opening 133 is provided at the position of the insulating member 13 corresponding to the explosion-proof valve 16, and the opening 133 connects the side of the insulating member 13 close to the electrode assembly 12 and the side of the insulating member 13 close to the explosion-proof valve 16, and is used to allow the gas generated by the thermal runaway of the battery cell 10 to flow from the opening 133 to the explosion-proof valve 16 when the internal pressure (or temperature) of the battery cell 10 reaches a threshold value, and to be discharged directionally through the explosion-proof valve 16.

[0115] See also Figure 3 , Figure 4 , Figure 5 , Figure 6 Some embodiments of the present application provide a battery cell 10, which includes a shell 11, an electrode assembly 12 and an exhaust bracket 17. The shell 11 includes a first wall 113. The electrode assembly 12 is accommodated in the shell 11. The exhaust bracket 17 is fixed to the side of the first wall 113 facing the electrode assembly 12, and is used to support the electrode assembly 12 in the event of thermal runaway of the battery cell 10. The exhaust bracket 17 is provided with a first channel 171 that runs through along a first direction x, and the first direction x intersects with the thickness direction z of the first wall 113. Each first channel 171 is provided corresponding to an electrode assembly 12.

[0116] It should be noted that the housing 11 is a component that isolates the internal environment of the battery cell 10 from the external environment. In addition, other related descriptions of the housing 11 can be found in the above text, and will not be repeated here.

[0117] The first wall 113 is a wall portion of the housing 11 for directional exhaust, and the first wall 113 may be a top wall, a bottom wall, or a side wall of the housing 11. In some embodiments, the housing 11 may include a shell 111 and an end cover 112 covering the shell 111, and the end cover 112 may be the first wall 113. In some embodiments, an explosion-proof valve 16 may be provided on the first wall 113, and the explosion-proof valve 16 may be used to release the internal pressure when the internal pressure (or temperature) of the battery cell 10 reaches a threshold value, allowing the gas generated by thermal runaway of the battery cell 10 to be directional discharged through the explosion-proof valve 16.

[0118] It should also be noted that the electrode assembly 12 is a component in the battery cell 10 where an electrochemical reaction occurs. The battery cell 10 may be provided with one or at least two electrode assemblies 12. The electrode assembly 12 may be accommodated in the internal space enclosed by the housing 11. In addition, other related descriptions of the electrode assembly 12 may be referred to above, and will not be repeated here.

[0119] It should also be noted that the exhaust bracket 17 is fixed to the side of the first wall 113 facing the electrode assembly 12, that is, the exhaust bracket 17 is arranged between the first wall 113 and the electrode assembly 12, and is fixedly connected to the first wall 113. Based on this, the installation position and installation state of the exhaust bracket 17 can be fixed relative to the first wall 113, so that in the case of thermal runaway of the battery cell 10, even under the action of air pressure impact force or other forces, the exhaust bracket 17 can also stabilize its installation position and installation state, thereby enabling the exhaust bracket 17 to reliably function, and reducing the risk of the exhaust bracket 17 damaging the diaphragm of the electrode assembly 12 due to displacement, and reducing the risk of the exhaust bracket 17 damaging the diaphragm of the electrode assembly 12 and causing additional short circuit, overheating, smoke, fire, etc. The fixing method of the exhaust bracket 17 to the first wall 113 can be, but not limited to, welding, riveting, bonding, etc.

[0120] The exhaust bracket 17 is used to support the electrode assembly 12 in the event of thermal runaway of the battery cell 10. That is, in the event of thermal runaway of the battery cell 10, the exhaust bracket 17 can be supported between the first wall 113 and the electrode assembly 12 to prevent the portion of the electrode assembly 12 supported by the exhaust bracket 17 from moving toward the first wall 113 under the impact of air pressure. Based on this, the exhaust bracket 17 can be used to support a gap space and an exhaust space between the first wall 113 and the portion of the electrode assembly 12 supported by the exhaust bracket 17. Of course, in the event of thermal runaway of the battery cell 10, the portion of the electrode assembly 12 that is not supported by the exhaust bracket 17 may still move toward the first wall 113 under the impact of air pressure and abut against the first wall 113. Of course, in some embodiments, the exhaust bracket 17 can support the electrode assembly 12 regardless of whether the battery cell 10 has thermal runaway.

[0121] The exhaust bracket 17 is provided with a first channel 171 extending along a first direction x. The first direction x intersects with the thickness direction z of the first wall 113. In some embodiments, the first direction x is perpendicular to the thickness direction z of the first wall 113, and in particular, the first direction x may be parallel to the length direction of the electrode assembly 12. Based on this, in the event of thermal runaway of the battery cell 10, especially when the exhaust bracket 17 is supported between the first wall 113 and the electrode assembly 12, an exhaust channel can be formed through the first channel 171 to promote the connectivity of the internal space of the battery cell 10, especially to enable the gas generated by the thermal runaway of the battery cell 10 to flow between the first wall 113 and the electrode assembly 12 through the first channel 171, and especially to enable the gas generated on the side of the electrode assembly 12 to flow to the directional exhaust position of the first wall 113 (for example, the explosion-proof valve 16) through the first channel 171, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell 10, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the outer shell 11, reducing the risk of cracking of the outer shell 11 (especially the connecting seam of the outer shell 11), and reducing the risk of cracking or even explosion of the battery cell 10.

[0122] The exhaust bracket 17 is provided with first channels 171 whose number is less than or equal to the number of electrode assemblies 12, and each first channel 171 is provided corresponding to one electrode assembly 12. Figure 3 , Figure 4 , Figure 6 As shown, in some embodiments, there are four electrode assemblies 12, and the exhaust channel is provided with two first channels 171, and the two first channels 171 are arranged corresponding to two of the electrode assemblies 12. Based on this, the first channels 171 can be enabled to discharge the gas generated by the thermal runaway of the electrode assembly 12 arranged corresponding thereto in a targeted, timely and rapid manner, thereby optimizing the exhaust effect.

[0123] In summary, the battery cell 10 provided in the embodiment of the present application can support the electrode assembly 12 through the exhaust bracket 17 fixed to the first wall 113 in the event of thermal runaway, so as to prevent the portion of the electrode assembly 12 supported by the exhaust bracket 17 from moving toward the direction close to the first wall 113. Based on this, an exhaust channel flowing along the first direction x can be formed between the portion of the electrode assembly 12 supported by the exhaust bracket 17 and the first wall 113 through the first channel 171 of the exhaust bracket 17, thereby promoting the circulation of the internal space of the battery cell 10, and promoting the gas generated by the thermal runaway of the electrode assembly 12 to flow to the directional exhaust position of the first wall 113, especially promoting the gas generated at the side of the electrode assembly 12 to flow to the directional exhaust position of the first wall 113, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell 10, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the shell 11, and reducing the risk of cracking of the shell 11 (especially the connection seam of the shell 11). In addition, each first channel 171 of the exhaust bracket 17 is also respectively arranged corresponding to an electrode assembly 12, based on which the first channel 171 can be enabled to discharge the gas generated by the thermal runaway of the electrode assembly 12 corresponding thereto in a targeted, timely and rapid manner, thereby optimizing the exhaust effect and exhaust efficiency. Thus, the risk of cracking or even explosion of the battery cell 10 (especially at the weld) can be effectively reduced, and the reliability of the battery cell 10 can be improved.

[0124] This embodiment is particularly suitable for battery cells 10 such as high-nickel or high-nickel plus silicon systems, which may have a more violent thermal runaway reaction.

[0125] See also Figure 3 , Figure 4 , Figure 6 In some embodiments of the present application, a plurality of electrode assemblies 12 are provided, and each electrode assembly 12 is arranged along the second direction y, and the second direction y is perpendicular to the first direction x. The exhaust bracket 17 is provided with two first channels 171, and the two first channels 171 are arranged at intervals along the second direction y, and the two first channels 171 are arranged corresponding to two of the electrode assemblies 12.

[0126] It should be noted that at least two electrode assemblies 12 may be provided in the battery cell 10. Each electrode assembly 12 may be arranged side by side along a second direction y perpendicular to the first direction x. In this case, the exhaust bracket 17 may be provided with two first channels 171 both extending along the first direction x, and the two first channels 171 are arranged at intervals along the second direction y, and the two first channels 171 are arranged corresponding to two of each electrode assembly 12. Figure 3 , Figure 4 , Figure 6As shown, in some embodiments, four electrode assemblies 12 are provided, and the four electrode assemblies 12 are arranged side by side along the second direction y. The exhaust bracket 17 is provided with two first channels 171 , and the two first channels 171 are arranged corresponding to two of the four electrode assemblies 12 .

[0127] By adopting the above-mentioned scheme, in the event of thermal runaway of the battery cell 10, at least two electrode assemblies 12 can be supported by the exhaust bracket 17 to prevent the corresponding parts of the at least two electrode assemblies 12 from moving toward the first wall 113, so that a larger gap space and exhaust space can be supported between each electrode assembly 12 and the first wall 113 through the exhaust bracket 17. On this basis, two first channels 171 of the exhaust bracket 17, which are spaced apart along the second direction y and pass through the first direction x, can form two parallel exhaust channels between the two electrode assemblies 12 and the first wall 113. Based on this, the exhaust bracket 17 can be conveniently used to discharge the gas generated by the thermal runaway of at least two electrode assemblies 12 in a focused, timely and rapid manner through the two first channels 171. Therefore, the exhaust area of ​​the exhaust bracket 17 can be optimized on the basis of taking into account the structural strength and support strength of the exhaust bracket 17, and the exhaust effect and efficiency can be optimized, thereby promoting the directional and rapid exhaust of the gas, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the outer shell 11, reducing the risk of cracking or even explosion of the battery cell 10 (especially at the weld), and improving the reliability of the battery cell 10.

[0128] Of course, in other embodiments, according to the number of electrode assemblies 12 , the exhaust bracket 17 may be provided with one or at least three first channels 171 as needed, and each first channel 171 may be provided corresponding to one electrode assembly 12 .

[0129] See also Figure 3 , Figure 6 , Figure 7 In some embodiments of the present application, the two first channels 171 of the exhaust bracket 17 are symmetrically distributed about the center line L of the first wall 113 along the second direction y.

[0130] It should be noted that the two first channels 171 of the exhaust bracket 17 may be symmetrically arranged relative to the center line L of the first wall 113 along the second direction y, that is, the two first channels 171 of the exhaust bracket 17 are symmetrically arranged, and the symmetry line coincides with the center line L of the first wall 113 along the second direction y. In combination with the previous embodiment, the two first channels 171 of the exhaust bracket 17 will be arranged corresponding to the two electrode assemblies 12 centrally arranged in each electrode assembly 12.

[0131] Since the gas generated by thermal runaway of the electrode assembly 12 located at the end side of each electrode assembly 12 arranged side by side along the second direction y may flow to the side away from the adjacent electrode assembly 12, but the exhaust path of the gas generated by thermal runaway of the electrode assembly 12 located in the middle is significantly less, resulting in a greater risk of gas generated by thermal runaway of the middle electrode assembly 12 accumulating in the small space enclosed by the side of the electrode assembly 12 and the outer shell 11. In addition, compared with the corner area of ​​the connection seam of the outer shell 11, the connection strength of the middle area of ​​the connection seam of the outer shell 11 will be relatively weak. Therefore, by adopting the above scheme, by making the two first channels 171 of the exhaust bracket 17 symmetrically distributed about the center line L of the first wall 113 along the second direction y, in the event of thermal runaway of the battery cell 10, the two first channels 171 of the exhaust bracket 17 can be enabled to focus on, promptly and quickly exhaust the gas generated by thermal runaway of the electrode assembly 12 in the center. Based on this, we can focus on optimizing the exhaust effect and efficiency of the exhaust bracket 17 on the middle area of ​​each electrode assembly 12, which can promote the directional and rapid exhaust of gas, reduce the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the outer shell 11, and reduce the risk of cracking or even explosion of the battery cell 10 (especially the middle area of ​​the connection seam of the outer shell 11), thereby improving the reliability of the battery cell 10.

[0132] Furthermore, by symmetrically distributing the two first channels 171 of the exhaust bracket 17 about the center line L of the first wall 113 along the second direction y, the layout of the first channels 171 of the exhaust bracket 17 can be balanced and optimized. Based on this, in the case of thermal runaway of the battery cell 10, the exhaust bracket 17 can provide a balanced exhaust effect on the opposite sides of the center line L of the first wall 113 along the second direction y through the two first channels 171, thereby optimizing the exhaust effect and exhaust efficiency, reducing the risk of gas accumulation on one side, reducing the risk of cracking or even explosion of the battery cell 10, and improving the reliability of the battery cell 10.

[0133] Of course, in other embodiments, the two first channels 171 of the exhaust bracket 17 may be symmetrically arranged or asymmetrically arranged. When the two first channels 171 of the exhaust bracket 17 are symmetrically arranged, the symmetry line between the two first channels 171 may deviate from the center line L of the first wall 113 along the second direction y.

[0134] See also Figure 3 , Figure 4 , Figure 7 In some embodiments of the present application, a plurality of exhaust brackets 17 are provided.

[0135] By adopting the above scheme, a plurality of exhaust brackets 17 can be provided so that when thermal runaway occurs in the battery cell 10, the electrode assembly 12 can be supported together by the plurality of exhaust brackets 17. Based on this, the supporting effect of each exhaust bracket 17 on the electrode assembly 12 can be enhanced, the supporting pressure of each exhaust bracket 17 can be dispersed and uniform, and each exhaust bracket 17 can support a stable and larger gap space and exhaust space between each electrode assembly 12 and the first wall 113, thereby promoting the connectivity of the internal space of the battery cell 10, promoting the directional and rapid discharge of gas, and reducing the risk of cracking or even explosion of the battery cell 10 (especially at the weld).

[0136] Of course, in other embodiments, only one exhaust bracket 17 may be provided.

[0137] See also Figure 3 , Figure 4 , Figure 7 In some embodiments of the present application, at least two exhaust brackets 17 are arranged at intervals along the first direction x.

[0138] It should be noted that, when there are multiple exhaust brackets 17, at least two exhaust brackets 17 are arranged side by side and spaced apart along the first direction x. Moreover, at least two exhaust brackets 17 arranged side by side and spaced apart along the first direction x can support the same part of the electrode assembly 12 together.

[0139] In some embodiments, all exhaust brackets 17 are arranged side by side and spaced apart along the first direction x.

[0140] In other embodiments, among the exhaust brackets 17, some of the exhaust brackets 17 are arranged side by side and spaced apart along the first direction x, and the remaining exhaust brackets 17 are flexibly arranged as needed, for example, the exhaust brackets 17 may be arranged in a matrix.

[0141] By adopting the above solution, by arranging at least two exhaust brackets 17 at intervals along the first direction x, it is convenient for these exhaust brackets 17 to support the same part of the electrode assembly 12 together. Based on this, it is convenient to support a stable gap space and exhaust space between the same part of the electrode assembly 12 and the first wall 113 through these exhaust brackets 17 in the case of thermal runaway of the battery cell 10, and reduce the risk of the exhaust channel being disconnected and partially blocked due to the partial abutment of this part of the electrode assembly 12 to the first wall 113. In this way, the internal space of the battery cell 10 can be stably and reliably connected, the directional and rapid exhaust of gas can be promoted, and the risk of cracking or even explosion of the battery cell 10 (especially at the weld) can be reduced.

[0142] See also Figure 3 , Figure 4 , Figure 7In some embodiments of the present application, at least two exhaust brackets 17 are disposed at opposite ends of the first wall 113 along the first direction x.

[0143] It should be noted that when there are multiple exhaust brackets 17, at least two exhaust brackets 17 are disposed at opposite ends of the first wall 113 along the first direction x. These exhaust brackets 17 may be arranged side by side along the first direction x, or may not be arranged side by side along the first direction x.

[0144] By adopting the above scheme, by arranging at least two exhaust brackets 17 at opposite ends of the first wall 113 along the first direction x, the supporting effect of the exhaust bracket 17 at the end of the first wall 113 along the first direction x can be optimized, the spatial connection between the end and the middle of the first wall 113 along the first direction x can be promoted, and the gas can be directed to flow from the end to the middle of the first wall 113 along the first direction x. Based on this, the internal space of the battery cell 10 can be reliably connected, especially the space between the end and the middle of the first wall 113 along the first direction x can be connected, so as to promote the directional and rapid discharge of gas, reduce the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the shell 11, and reduce the risk of cracking or even explosion of the battery cell 10 (especially at the weld).

[0145] This embodiment is particularly suitable for application in combination with "at least two exhaust brackets 17 are arranged at intervals along the first direction x". That is, at least two exhaust brackets 17 are arranged at opposite ends of the first wall 113 along the first direction x, and these exhaust brackets 17 are arranged at intervals along the first direction x. Figure 3 , Figure 4 , Figure 7 As shown, in some embodiments, two exhaust brackets 17 are provided, and the two exhaust brackets 17 are arranged at intervals along the first direction x and are respectively arranged at opposite ends of the first wall 113 along the first direction x. Such an arrangement can combine the advantages of the two embodiments, comprehensively optimize the supporting effect of the exhaust bracket 17, and facilitate the exhaust bracket 17 to support a suitable, stable, and larger exhaust space between each electrode assembly 12 and the first wall 113.

[0146] Of course, in other embodiments, the plurality of exhaust brackets 17 may be arranged in other ways, such as a circular array arrangement.

[0147] See also Figure 3 , Figure 4 , Figure 6 In some embodiments of the present application, the battery cell 10 further includes an insulating member 13. The insulating member 13 is disposed on a side of the first wall 113 facing the electrode assembly 12, and insulates and isolates the first wall 113 and the electrode assembly 12. A receiving cavity 134 is disposed on a side of the insulating member 13 facing the first wall 113, and the exhaust bracket 17 is received in the receiving cavity 134.

[0148] It should be noted that the insulating member 13 is a component with insulating properties. The material of the insulating member 13 may be, but is not limited to, polypropylene (PP) material, polyphenylene sulfide (PPS) material, or soluble polytetrafluoroethylene (PFA) material. The insulating member 13 is disposed in the housing 11, in particular, on the side of the first wall 113 facing the electrode assembly 12, that is, between the first wall 113 and the electrode assembly 12. The insulating member 13 is connected to the first wall 113, and the connection method can be fixed connection or detachable connection, such as bonding, etc.

[0149] During normal use of the battery cell 10, the insulating member 13 can insulate and isolate the first wall 113 and the electrode assembly 12 without affecting the electrical connection between the tab 122 of the electrode assembly 12 and the corresponding electrode terminal 14, so as to reduce the risk of short circuit, current leakage and the like. Of course, the insulating member 13 can also play other roles. For example, the insulating member 13 can be fixed to the first wall 113 and abut the electrode assembly 12 to fill the gap between the electrode assembly 12 and the first wall 113, and tightly fix the electrode assembly 12, so that the electrode assembly 12 will not move or shake relatively during the use of the battery cell 10, and the structural integrity of the battery cell 10 can be maintained, and the risk of loosening or deformation of the electrode assembly 12 can be reduced.

[0150] The material of the insulating member 13 can be flexibly set as needed so that the insulating member 13 has a desired melting point. In the case of thermal runaway of the battery cell 10, the insulating member 13 may not melt, or may melt when the thermal runaway temperature of the battery cell 10 exceeds its melting point.

[0151] It should also be noted that a receiving cavity 134 is provided on one side of the insulating member 13 facing the first wall 113, and one receiving cavity 134 can be used to receive one or more exhaust brackets 17. That is, the receiving cavity 134 can be arranged in alignment with at least one exhaust bracket 17 fixed to the first wall 113, so that the exhaust bracket 17 can be received in the corresponding receiving cavity 134.

[0152] By adopting the above scheme, during the normal use of the battery cell 10 and in the early stage of thermal runaway of the battery cell 10, the first wall 113 and the electrode assembly 12 can be insulated and isolated by the unmelted insulating member 13 disposed on the side of the first wall 113 facing the electrode assembly 12, so as to reduce the risk of short circuit, current leakage and the like. In addition, the accommodating cavity 134 can be provided by the insulating member 13 to accommodate the exhaust bracket 17, so that the exhaust bracket 17 can share space with the insulating member 13 in the thickness direction z of the first wall 113, thereby reducing the additional space occupied by the exhaust bracket 17 in the thickness direction z of the first wall 113, and improving the space utilization and energy density of the battery cell 10. In addition, the strength of the corresponding area of ​​the insulating member 13 can be correspondingly enhanced by the exhaust bracket 17 to enhance the supporting effect of the corresponding area of ​​the insulating member 13 on the electrode assembly 12, thereby stabilizing the position and structure of the electrode assembly 12, reducing the relative movement or shaking of the electrode assembly 12, and reducing the risk of loosening or deformation of the electrode assembly 12.

[0153] By adopting the above scheme, when the battery cell 10 undergoes thermal runaway and the insulating member 13 melts because the thermal runaway temperature of the battery cell 10 exceeds its melting point, the electrode assembly 12 can be supported by the exhaust bracket 17 exposed to the insulating member 13 to prevent the portion of the electrode assembly 12 supported by the exhaust bracket 17 from moving toward the first wall 113, thereby supporting a gap space and an exhaust space between the electrode assembly 12 and the first wall 113, and facilitating the communication of the internal space of the battery cell 10 through the first channel 171 of the exhaust bracket 17, thereby promoting the directional and rapid discharge of gas, and reducing the risk of cracking or even explosion of the battery cell 10 (especially at the weld).

[0154] Of course, in other embodiments, if the surface of the exhaust bracket 17 has insulating properties, for example, the surface of the exhaust bracket 17 has an insulating layer, or the exhaust bracket 17 is a non-metallic part, etc., the insulating part 13 can be omitted, and the exhaust bracket 17 can directly support the electrode assembly 12 to play the role of "insulating and isolating the first wall 113 and the electrode assembly 12" and "blocking the electrode assembly 12 from moving toward the first wall 113".

[0155] See also Figure 3 , Figure 4 In some embodiments of the present application, the insulating member 13 includes a main body 131 and a plurality of bosses 132. The plurality of bosses 132 are arranged at intervals along the first direction x. The main body 131 connects the bosses 132 and the first wall 113. The accommodating cavity 134 is provided in the bosses 132.

[0156] It should be noted that the main body 131 is the portion of the insulating member 13 connected to the first wall 113 facing the electrode assembly 12, and is mainly used to insulate and isolate the first wall 113 from the electrode assembly 12. The main body 131 and the first wall 113 may be connected by, but not limited to, bonding or other methods.

[0157] The insulating member 13 includes at least one boss 132. When at least two bosses 132 are provided, the bosses 132 are arranged spaced apart from each other along the first direction x. The boss 132 is a convex structure of the insulating member 13 connected to the side of the main body 131 facing the electrode assembly 12. The boss 132 and the main body 131 can be connected as one piece or as a separate body. The boss 132 is used to abut the electrode assembly 12, that is, the side of the boss 132 away from the main body 131 abuts against the electrode assembly 12.

[0158] By adopting the above solution, the insulating member 13 can reliably insulate and isolate the first wall 113 and the electrode assembly 12 through the main body 131 connected to the first wall 113 facing the electrode assembly 12, thereby reducing the risk of short circuit, current leakage, etc. The insulating member 13 can also abut the electrode assembly 12 through the boss 132 connected to the main body 131 facing the electrode assembly 12 to fill the gap between the electrode assembly 12 and the first wall 113, and tightly fix the electrode assembly 12, thereby reducing the relative movement or shaking of the electrode assembly 12, stabilizing the position and structure of the electrode assembly 12, and reducing the risk of loosening or deformation of the electrode assembly 12.

[0159] It should also be noted that the thickness of the insulating member 13 is greater at the position corresponding to the boss 132. The thickness of the insulating member 13 is the dimension of the insulating member 13 along the thickness direction z of the first wall 113. Therefore, it is convenient to set the accommodating cavity 134 at the position of the insulating member 13 corresponding to the boss 132 to accommodate the exhaust bracket 17.

[0160] By adopting the above scheme, since the thickness of the insulating member 13 at the position corresponding to the boss 132 is relatively large, by providing the accommodating cavity 134 at the position corresponding to the boss 132 of the insulating member 13, it is convenient to process the accommodating cavity 134, and it is also convenient to process a larger accommodating cavity 134 to accommodate the exhaust bracket 17. Based on this, on the one hand, the processing convenience of the accommodating cavity 134 can be improved, and the influence of the processing of the accommodating cavity 134 on the structural strength of the insulating member 13 can be reduced, stress concentration can be reduced, and the risk of damage to the insulating member 13 can be reduced, so that the insulation isolation and other functions of the insulating member 13 can be maintained, and the use performance and service life of the insulating member 13 can be improved. On the other hand, the accommodating cavity 134 can accommodate more parts of the exhaust bracket 17, so that the exhaust bracket 17 can share as much space as possible with the insulating member 13 in the thickness direction z of the first wall 113, so that the additional occupied space of the exhaust bracket 17 in the thickness direction z of the first wall 113 can be reduced, and the space utilization rate and energy density of the battery cell 10 can be improved.

[0161] See also Figure 3 , Figure 4 , Figure 8 In some embodiments of the present application, the cross-sectional area of ​​the first channel 171 of the exhaust bracket 17 is S1, the area of ​​the side surface of the corresponding boss 132 along the first direction x is S2, the capacity of the battery cell 10 is C, and the mass percentage of nickel in the positive electrode active material contained in the battery cell 10 is N. 0.125*(C / 40)*N≤S1≤0.25*S2.

[0162] It should be noted that the cross section of the first channel 171 of the exhaust bracket 17 is the cross section of the first channel 171 perpendicular to the first direction x. The cross-sectional area S1 of the first channel 171 is the area of ​​the cross section of the first channel 171 perpendicular to the first direction x. Figure 8 As shown, in some embodiments, the cross-sectional shape of the first channel 171 of the exhaust bracket 17 is rectangular, and the cross-sectional area S1 of the first channel 171 of the exhaust bracket 17 is equal to the length of the first support wall 1731 multiplied by the length of the second support wall 1732 .

[0163] The "corresponding boss 132" refers to the boss 132 that accommodates the exhaust bracket 17. The corresponding boss 132 has two opposite side surfaces along the first direction x, and the area S2 of the side surface of the corresponding boss 132 along the first direction x may be the area of ​​any one of the two side surfaces.

[0164] It should also be noted that the capacity C of the battery cell 10 refers to the amount of electrical energy that the battery cell 10 can store. It is usually expressed in ampere-hours (Ah), that is, the current that can be provided per hour of discharge. The size of the capacity C of the battery cell 10 depends on the characteristics and design of the chemical reaction inside the battery cell 10, and the capacity C of different types of battery cells 10 will be different. In some embodiments, the capacity C of the battery cell 10 can be measured by a charge and discharge test. The steps of measuring the capacity C of the battery cell 10 may include: charging the battery cell 10 to a fully charged state so that the chemical substances inside the battery cell 10 are fully charged; discharging the battery cell 10 with a known constant current and measuring the discharge time; using the current and time data during the discharge process, the capacity C of the battery cell 10 is calculated by the formula, the capacity C of the battery cell 10 (unit: ampere-hour, Ah) = current (unit: ampere, A) * time (unit: hour, h).

[0165] It should also be noted that the electrode assembly 12 includes a positive electrode sheet, a negative electrode sheet and a separator, and the separator separates the positive electrode sheet from the negative electrode sheet. The positive electrode sheet, the separator and the negative electrode sheet can be processed by winding, stacking or other methods to form the electrode assembly 12. Among them, the positive electrode sheet includes a positive current collector and a positive active layer, and the positive active layer is arranged on the side of the positive current collector along the thickness direction. The area of ​​the positive current collector where the positive active layer is not arranged can be used as a positive electrode ear 122a, and the positive electrode ear 122a is the current output end of the positive electrode sheet. Among them, the material of the positive current collector may include but is not limited to aluminum and the like. The positive active material of the positive active layer may include but is not limited to nickel, manganese, cobalt and the like. The positive active material composition of different types of battery cells 10 will be different.

[0166] The positive electrode active material contained in the battery cell 10 is the positive electrode active material of the positive electrode active layer of all positive electrode sheets contained in the battery cell 10. The mass percentage content N of nickel in the positive electrode active material in the battery cell 10 is equal to: (mass of nickel / total mass of positive electrode active material)*100%. In some embodiments, a chemical analysis instrument, such as an atomic absorption spectrometer (AAS), an inductively coupled plasma emission spectrometer (ICP-OES) or a mass spectrometer (MS), etc., can be used to analyze the element content in the sample to determine the mass percentage content N of nickel in the positive electrode active material in the battery cell 10. In other embodiments, a certain mass of sample can be taken, then dissolved or converted into a form suitable for analysis, and then the nickel content in the solution can be measured using a chemical analysis instrument, and then the mass percentage content N of nickel in the positive electrode active material in the battery cell 10 can be calculated by comparing the nickel content in the sample with the content of other elements.

[0167] Since the larger the capacity C of the battery cell 10, the larger the gas production of the battery cell 10 during thermal runaway, the greater the exhaust demand. Also, due to the difference in the system of the battery cell 10, the larger the mass percentage N of nickel in the positive electrode active material in the battery cell 10, the faster the gas production rate of the battery cell 10 during thermal runaway, the larger the gas production, and the greater the exhaust demand. Therefore, the cross-sectional area S1 of the first channel 171 of the exhaust bracket 17 is closely related to the capacity C of the battery cell 10 and the mass percentage N of nickel in the positive electrode active material in the battery cell 10.

[0168] By adopting the above scheme, according to the capacity C of the battery cell 10 and the mass percentage N of nickel in the positive electrode active material in the battery cell 10, by making the cross-sectional area S1 of a first channel 171 greater than or equal to 0.125*(C / 40)*N, the exhaust bracket 17 can provide sufficient exhaust area through the first channel 171 with sufficient cross-sectional area in the event of thermal runaway of the battery cell 10, thereby optimizing the exhaust effect and exhaust efficiency and reducing the risk of cracking or even explosion of the battery cell 10 (especially at the weld).

[0169] On this basis, according to the area S2 of the side surface of the corresponding boss 132 accommodating the exhaust bracket 17 along the first direction x, by making the cross-sectional area S1 of the first channel 171 less than or equal to 0.25*S2, the sizes of the first channel 171 and the exhaust bracket 17 can be coordinated so that the exhaust bracket 17 can be accommodated in the accommodating cavity 134 opened by the insulating member 13, so that the exhaust bracket 17 can share as much space as possible with the insulating member 13, thereby improving the space utilization and energy density of the battery cell 10.

[0170] See also Figure 3 , Figure 4 In some embodiments of the present application, the insulating member 13 has a first end surface 135 along the first direction x, and the first end surface 135 is provided with at least one second channel 136 , and the second channel 136 is connected to the side of the insulating member 13 facing the first wall 113 .

[0171] It should be noted that the insulating member 13 has two opposite end surfaces along the first direction x, and at least one of the two end surfaces may be the first end surface 135. The first end surface 135 is provided with one or more second channels 136, and the second channels 136 are bent and extended and connected to the side of the insulating member 13 facing the first wall 113. In some embodiments, the bent extension path of the second channel 136 may be in a right angle.

[0172] By adopting the above scheme, when the battery cell 10 has thermal runaway and the insulating member 13 has not melted because the thermal runaway temperature of the battery cell 10 has not exceeded its melting point, the second channel 136 provided on the first end surface 135 of the insulating member 13 can promote the circulation of the internal space of the battery cell 10, and can enable the gas generated by the thermal runaway of the electrode assembly 12 to flow to the directional exhaust position of the first wall 113, especially to enable the gas generated on the side of the electrode assembly 12 to flow to the directional exhaust position of the first wall 113 through the second channel 136, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell 10, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the outer shell 11, and reducing the risk of cracking of the outer shell 11 (especially the connecting seam of the outer shell 11).

[0173] See also Figure 3 , Figure 4 In some embodiments of the present application, the total occupied area of ​​each second channel 136 on the first end surface 135 is S3, the area of ​​the first end surface 135 is S4, the capacity of the battery cell 10 is C, and the mass percentage of nickel in the positive electrode active material contained in the battery cell 10 is N. 0.125*(C / 10)*N≤S3≤0.5*S4.

[0174] It should be noted that one or more second channels 136 may be provided on the first end surface 135, and the total occupied area of ​​each second channel 136 on the first end surface 135 is S3. S3 is less than or equal to 0.5*S4, that is, less than or equal to one half of the area of ​​the first end surface 135. In this way, the total occupied area of ​​each second channel 136 on the first end surface 135 can be controlled not to be too large, so as to reduce the influence of the arrangement of each second channel 136 on the structural strength of the insulating member 13 (especially the boss 132).

[0175] It should also be noted that the capacity C of the battery cell 10 refers to the amount of electrical energy that the battery cell 10 can store. It is usually expressed in ampere-hours (Ah), that is, the current that can be provided per hour of discharge. The size of the capacity C of the battery cell 10 depends on the characteristics and design of the chemical reaction inside the battery cell 10, and the capacity C of different types of battery cells 10 will be different. In some embodiments, the capacity C of the battery cell 10 can be measured by a charge and discharge test. The steps of measuring the capacity C of the battery cell 10 may include: charging the battery cell 10 to a fully charged state so that the chemical substances inside the battery cell 10 are fully charged; discharging the battery cell 10 with a known constant current and measuring the discharge time; using the current and time data during the discharge process, the capacity C of the battery cell 10 is calculated by the formula, the capacity C of the battery cell 10 (unit: ampere-hour, Ah) = current (unit: ampere, A) * time (unit: hour, h).

[0176] It should also be noted that the electrode assembly 12 includes a positive electrode sheet, a negative electrode sheet and a separator, and the separator separates the positive electrode sheet from the negative electrode sheet. The positive electrode sheet, the separator and the negative electrode sheet can be processed by winding, stacking or other methods to form the electrode assembly 12. Among them, the positive electrode sheet includes a positive current collector and a positive active layer, and the positive active layer is arranged on the side of the positive current collector along the thickness direction. The area of ​​the positive current collector where the positive active layer is not arranged can be used as a positive electrode ear 122a, and the positive electrode ear 122a is the current output end of the positive electrode sheet. Among them, the material of the positive current collector may include but is not limited to aluminum and the like. The positive active material of the positive active layer may include but is not limited to nickel, manganese, cobalt and the like. The positive active material composition of different types of battery cells 10 will be different.

[0177] The positive electrode active material contained in the battery cell 10 is the positive electrode active material of the positive electrode active layer of all positive electrode sheets contained in the battery cell 10. The mass percentage content N of nickel in the positive electrode active material in the battery cell 10 is equal to: (mass of nickel / total mass of positive electrode active material)*100%. In some embodiments, a chemical analysis instrument, such as an atomic absorption spectrometer (AAS), an inductively coupled plasma emission spectrometer (ICP-OES) or a mass spectrometer (MS), etc., can be used to analyze the element content in the sample to determine the mass percentage content N of nickel in the positive electrode active material in the battery cell 10. In other embodiments, a certain mass of sample can be taken, then dissolved or converted into a form suitable for analysis, and then the nickel content in the solution can be measured using a chemical analysis instrument, and then the mass percentage content N of nickel in the positive electrode active material in the battery cell 10 can be calculated by comparing the nickel content in the sample with the content of other elements.

[0178] Since the larger the capacity C of the battery cell 10, the larger the gas production of the battery cell 10 during thermal runaway, the greater the exhaust demand. Also, due to the difference in the system of the battery cell 10, the larger the mass percentage N of nickel in the positive electrode active material in the battery cell 10, the faster the gas production rate of the battery cell 10 during thermal runaway, the larger the gas production, and the greater the exhaust demand. Therefore, the total occupied area S3 of each second channel 136 on the first end surface 135 is closely related to the capacity C of the battery cell 10 and the mass percentage N of nickel in the positive electrode active material in the battery cell 10.

[0179] By adopting the above scheme, according to the capacity C of the battery cell 10 and the mass percentage N of nickel in the positive electrode active material in the battery cell 10, by making the total occupied area S3 of each second channel 136 on the first end face 135 greater than or equal to 0.125*(C / 10)*N, when the battery cell 10 has thermal runaway and the insulating member 13 has not melted because the thermal runaway temperature of the battery cell 10 does not exceed its melting point, the insulating member 13 can provide sufficient exhaust area through each second channel 136, thereby optimizing the exhaust effect and exhaust efficiency, and reducing the risk of cracking or even explosion of the battery cell 10 (especially at the weld).

[0180] On this basis, according to the area S4 of the first end face 135, by making the total occupied area S3 of each second channel 136 on the first end face 135 less than or equal to 0.5*S4, the area ratio of each second channel 136 to the first end face 135 can be coordinated, so that the total occupied area of ​​each second channel 136 on the first end face 135 is not too large, thereby reducing the influence of the setting of each second channel 136 on the structural strength of the insulating member 13 (especially the boss 132), reducing stress concentration, and reducing the risk of damage to the insulating member 13, thereby maintaining the insulation isolation and other functions of the insulating member 13, and improving the performance and service life of the insulating member 13.

[0181] See also Figure 3 , Figure 4 , Figure 6 In some embodiments of the present application, the melting point of the exhaust bracket 17 is greater than the melting point of the insulating member 13. It should be noted that the exhaust bracket 17 is made of a high temperature resistant and non-melting material, so that the melting point of the exhaust bracket 17 is greater than the melting point of the insulating member 13.

[0182] By adopting the above scheme, by making the melting point of the exhaust bracket 17 greater than the melting point of the insulating member 13, the exhaust bracket 17 can be made difficult to melt than the insulating member 13. Based on this, when the battery cell 10 has thermal runaway and the insulating member 13 melts because the thermal runaway temperature of the battery cell 10 exceeds its melting point, the exhaust bracket 17 can be exposed to the insulating member 13, and in a difficult-to-melt, unmelted state, it can support the electrode assembly 12 to prevent the portion of the electrode assembly 12 supported by the exhaust bracket 17 from moving toward the first wall 113, so that a gap space and an exhaust space can be supported between the electrode assembly 12 and the first wall 113, and the first channel 171 of the exhaust bracket 17 can be facilitated to promote the communication of the internal space of the battery cell 10, so as to promote the directional and rapid discharge of gas, and reduce the risk of cracking or even explosion of the battery cell 10 (especially at the weld).

[0183] See also Figure 3 , Figure 4In some embodiments of the present application, the exhaust bracket 17 is a metal member. That is, the exhaust bracket 17 is made of metal material.

[0184] By adopting the above solution, by making the exhaust bracket 17 a metal part, on the one hand, it is easy to process and connect the exhaust bracket 17, especially to conveniently, quickly and firmly fix the exhaust bracket 17 to the first wall 113 by welding. On the other hand, the exhaust bracket 17 can have a high structural strength and melting point, and can maintain a stable shape and reliably support the electrode assembly 12 in the event of thermal runaway of the battery cell 10.

[0185] This embodiment is particularly suitable for application in combination with the embodiments related to the insulating part 13, so that the exhaust bracket 17, which is a metal part, is hidden and accommodated in the accommodating cavity 134 of the insulating part 13 during normal use of the battery cell 10. Based on this, the exhaust bracket 17, which is a metal part, and the electrode assembly 12 can be insulated and isolated by the insulating part 13, thereby reducing the risk of short circuit, current leakage and the like.

[0186] Of course, in other embodiments, the surface of the exhaust bracket 17 which is a metal part may be provided with an insulating layer so that the exhaust bracket 17 which is a metal part is insulated and isolated from the electrode assembly 12. In this case, the exhaust bracket 17 which is a metal part may not be used in combination with the relevant embodiments of the insulating part 13.

[0187] See also Figure 3 , Figure 4 In some embodiments of the present application, the exhaust bracket 17 is a non-metallic part. That is, the exhaust bracket 17 is made of a non-metallic material. For example, the exhaust bracket 17 can be a ceramic part, etc.

[0188] By adopting the above solution, the exhaust bracket 17 is made of a non-metallic part, which can reduce the weight of the exhaust bracket 17 and reduce the cost of the exhaust bracket 17. It is also convenient for the exhaust bracket 17 to be processed, formed, connected and fixed. For example, the exhaust bracket 17 can be fixed to the first wall 113 by bonding or the like.

[0189] Since the exhaust bracket 17, which is a non-metallic part, can be insulated and isolated from the electrode assembly 12, this embodiment can be applied in combination with the embodiments related to the insulating member 13, so that the exhaust bracket 17, which is a non-metallic part, is hidden and accommodated in the accommodation cavity 134 of the insulating member 13 during the normal use of the battery cell 10. This embodiment can also be applied without being combined with the embodiments related to the insulating member 13, so that the exhaust bracket 17, which is a non-metallic part, is exposed during the normal use of the battery cell 10.

[0190] See also Figure 3 , Figure 4 , Figure 8 , Fig. 9In some embodiments of the present application, the exhaust bracket 17 includes a connecting portion 172 and at least one supporting portion 173 , the connecting portion 172 is connected to the first wall 113 , and the supporting portion 173 is connected to a side of the connecting portion 172 facing away from the first wall 113 .

[0191] It should be noted that the connection portion 172 is a portion of the exhaust bracket 17 connected to the first wall 113. The connection between the connection portion 172 and the first wall 113 may be achieved by, but not limited to, welding or other methods.

[0192] The exhaust bracket 17 includes at least one support portion 173. When at least two support portions 173 are provided, the support portions 173 are arranged at intervals from each other. The support portion 173 is connected to the side of the connecting portion 172 away from the first wall 113. The support portion 173 and the connecting portion 172 can be connected in one piece or in a separate piece. The support portion 173 is used to support the electrode assembly 12 in the event of thermal runaway of the battery cell 10.

[0193] By adopting the above solution, the exhaust bracket 17 can be reliably fixed to the first wall 113 through the connecting portion 172. Based on this, the installation position and installation state of the exhaust bracket 17 can be fixed relative to the first wall 113, so that in the case of thermal runaway of the battery cell 10, even under the action of air pressure impact force or other forces, the exhaust bracket 17 can stabilize its installation position and installation state, thereby enabling the exhaust bracket 17 to reliably function, reducing the risk of the exhaust bracket 17 damaging the diaphragm of the electrode assembly 12 due to displacement, and reducing the risk of the exhaust bracket 17 damaging the diaphragm of the electrode assembly 12 and causing additional short circuits, overheating, smoke, fire, etc.

[0194] On this basis, the exhaust bracket 17 can also reliably support the electrode assembly 12 through the support portion 173 connected to the side of the connection portion 172 away from the first wall 113 when the battery cell 10 has thermal runaway. Based on this, the exhaust bracket 17 can support the gap space and exhaust space between the electrode assembly 12 and the first wall 113, and the exhaust bracket 17 can promote the communication of the internal space of the battery cell 10 through the first channel 171, so as to optimize the structure, utility and performance of the exhaust bracket 17.

[0195] See also Figure 3 , Figure 4 , Figure 8 , Fig. 9 In some embodiments of the present application, two support portions 173 are provided, and the two support portions 173 are respectively disposed at opposite ends of the connecting portion 172 , and each support portion 173 and the connecting portion 172 enclose a first channel 171 .

[0196] It should be noted that there are two support portions 173, one of which is disposed at one end of the connecting portion 172, and the other support portion 173 is disposed at the other end of the connecting portion 172. Each support portion 173 and the connecting portion 172 can enclose a first channel 171, that is, the exhaust bracket 17 has two first channels 171.

[0197] By adopting the above solution, the exhaust bracket 17 can optimize its structure and supporting function through the two supporting parts 173 disposed at opposite ends of the connecting part 172. Based on this, in the case of thermal runaway of the battery cell 10, the exhaust bracket 17 can support the electrode assembly 12 in a balanced and stable manner through the two supporting parts 173, so that the exhaust bracket 17 can support a stable and large gap space and exhaust space between the electrode assembly 12 and the first wall 113.

[0198] On this basis, the exhaust bracket 17 can also form two parallel exhaust channels through the two first channels 171 formed by the two supporting parts 173 to optimize the exhaust area of ​​the exhaust bracket 17, optimize the exhaust effect and exhaust efficiency, thereby promoting the directional and rapid discharge of gas, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the outer shell 11, reducing the risk of cracking or even explosion of the battery cell 10 (especially at the weld), and improving the reliability of the battery cell 10.

[0199] See also Figure 3 , Figure 4 , Figure 8 , Fig. 9 In some embodiments of the present application, the support portion 173 includes a first support wall 1731 and a second support wall 1732 , the first support wall 1731 is vertically connected to the connecting portion 172 , and the second support wall 1732 is bent and connected to an end of the first support wall 1731 away from the connecting portion 172 .

[0200] It should be noted that the first support wall 1731 is a portion of the support portion 173 connected to the connection portion 172. One end of the first support wall 1731 is connected to the connection portion 172, and the first support wall 1731 and the connection portion 172 may be connected in one piece or in a separate piece. The other end of the first support wall 1731 is extended in a direction away from the connection portion 172. The first support wall 1731 is perpendicular to the connection portion 172.

[0201] The second support wall 1732 is connected to one end of the first support wall 1731 away from the connecting portion 172, and is arranged at an angle with the first support wall 1731. The second support wall 1732 and the first support wall 1731 can be connected as one piece or separately. The angle between the second support wall 1732 and the first support wall 1731 can be, but is not limited to, a right angle. The first support wall 1731 is used to support the second support wall 1732, and the second support wall 1732 is used to support the electrode assembly 12 in the event of thermal runaway of the battery cell 10.

[0202] By adopting the above solution, the support portion 173 can enhance its own structural strength by setting the first support wall 1731 and the second support wall 1732, so that the support portion 173 can reliably play a supporting role. Based on this, in the case of thermal runaway of the battery cell 10, the support portion 173 of the exhaust bracket 17 can be supported between the connecting portion 172 and the second support wall 1732 through the first support wall 1731, and abut against the electrode assembly 12 through the second support wall 1732, so as to reliably support the electrode assembly 12. In this way, the structure of the exhaust bracket 17 can be optimized, so that the exhaust bracket 17 can support a stable and large gap space and exhaust space between the electrode assembly 12 and the first wall 113.

[0203] Furthermore, according to the angle between the first support wall 1731 and the second support wall 1732, as well as the size design of the first support wall 1731 and the size design of the second support wall 1732, the cross-sectional area of ​​the first channel 171 formed between the support portion 173 and the connecting portion 172 can be adjusted, thereby optimizing the exhaust area of ​​the exhaust bracket 17, and optimizing the exhaust effect and exhaust efficiency.

[0204] Of course, in other embodiments, the support portion 173 may include only the first support wall 1731 but not the second support wall 1732 .

[0205] See also Figure 3 , Figure 4 , Figure 8 , Fig. 9 In some embodiments of the present application, one end of each second support wall 1732 away from the first support wall 1731 is spaced apart from another second support wall 1732 .

[0206] It should be noted that the exhaust bracket 17 has two supporting parts 173, and each of the two supporting parts 173 has a second supporting wall 1732. Therefore, the exhaust bracket 17 has two second supporting walls 1732. One end of each second supporting wall 1732 away from the first supporting wall 1731 is spaced apart from the other second supporting wall 1732, that is, the ends of the two second supporting walls 1732 that are close to each other are spaced apart.

[0207] By adopting the above solution, the two second support walls 1732 of the exhaust bracket 17 can be arranged at intervals. Based on this, on the one hand, it is convenient for operators to flexibly and conveniently perform the connection (such as welding) operation between the exhaust bracket 17 and the first wall 113 through the interval space between the two second support walls 1732, thereby improving the connection convenience of the exhaust bracket 17. On the one hand, the processing of the two support parts 173 can be made independent of each other, and it is convenient to process and form the exhaust bracket 17 by means of pier forming, thereby improving the convenience of processing and forming the exhaust bracket 17.

[0208] On the other hand, the two second support walls 1732 can be made to move independently of each other. Based on this, when the support portion 173 supports the electrode assembly 12, the second support wall 1732 can be bent toward the connecting portion 172 relative to the first support wall 1731 under the action of impact force or other external force, so that the second support wall 1732, the first support wall 1731 and the connecting portion 172 can form a triangular stable structure. In this way, the structure and supporting effect of the exhaust bracket 17 can be optimized, the exhaust bracket 17 can be made to support the exhaust space between the electrode assembly 12 and the first wall 113 permanently and reliably, and the exhaust bracket 17 can be made to provide the first channel 171 between the electrode assembly 12 and the first wall 113 for the circulation of gas, which can reduce the risk of the exhaust bracket 17 being crushed by impact force or other external force and blocking the exhaust channel, thereby improving the performance and service life of the exhaust bracket 17, and optimizing the exhaust effect and exhaust efficiency.

[0209] See also Figure 3 , Figure 4 , Fig.10 , Fig.11 In some embodiments of the present application, one end of each second support wall 1732 away from the first support wall 1731 is connected to another second support wall 1732 through a weak portion 174 .

[0210] It should be noted that the exhaust bracket 17 has two supporting portions 173, and each of the two supporting portions 173 has a second supporting wall 1732. Therefore, the exhaust bracket 17 has two second supporting walls 1732. One end of each second supporting wall 1732 away from the first supporting wall 1731 is connected to the other second supporting wall 1732 through a weak portion 174, that is, the ends of the two second supporting walls 1732 close to each other are connected through the weak portion 174. The structural strength of the weak portion 174 is weaker than the structural strength of other positions of the second supporting portion 173. The weak portion 174 may be, but is not limited to, a thin-wall feature.

[0211] By adopting the above solution, the ends of the two second support walls 1732 of the exhaust bracket 17 that are close to each other can be connected via the weak portion 174. Based on this, in the early stage of the exhaust bracket 17 supporting the electrode assembly 12, the exhaust bracket 17 can support the electrode assembly 12 together by supporting each other via the two connected second support walls 1732, thereby optimizing the supporting effect of the exhaust bracket 17 on the electrode assembly 12.

[0212] In the later stage when the exhaust bracket 17 supports the electrode assembly 12, the second support wall 1732 can be bent toward the connecting portion 172 relative to the first support wall 1731 connected to each other under the action of impact force or other external force, so that the second support wall 1732, the first support wall 1731 and the connecting portion 172 can form a triangular stable structure, and the two second support walls 1732 can be arranged at an angle along the weak portion 174. In this way, the structure and supporting effect of the exhaust bracket 17 can be optimized, the exhaust bracket 17 can be supported between the electrode assembly 12 and the first wall 113 to form an exhaust space permanently and reliably, the exhaust bracket 17 can be provided between the electrode assembly 12 and the first wall 113 to provide a first channel 171 for circulating gas, and the risk of the exhaust bracket 17 being crushed by impact force or other external force to block the exhaust channel can be reduced, thereby improving the performance and service life of the exhaust bracket 17, and optimizing the exhaust effect and exhaust efficiency.

[0213] See also Figure 3 , Figure 4 In some embodiments of the present application, the exhaust bracket 17 is welded to the first wall 113 .

[0214] By adopting the above solution, by welding the exhaust bracket 17 to the first wall 113, the connection convenience, connection strength, connection firmness and durability between the exhaust bracket 17 and the first wall 113 can be improved, and the risk of loosening or detachment between the exhaust bracket 17 and the first wall 113 can be reduced.

[0215] Of course, in other embodiments, the exhaust bracket 17 and the first wall 113 may be fixedly connected by other means, such as riveting.

[0216] See also Figure 3 , Figure 4 In some embodiments of the present application, the material of the exhaust bracket 17 is the same as that of the first wall 113 .

[0217] It should be noted that the material of the exhaust bracket 17 is the same as that of the first wall 113. For example, the material of the first wall 113 is aluminum, and the material of the exhaust bracket 17 is also aluminum.

[0218] By adopting the above solution, by making the material of the exhaust bracket 17 the same as that of the first wall 113, the exhaust bracket 17 and the first wall 113 can be easily welded, which can help improve the connection convenience and connection strength between the exhaust bracket 17 and the first wall 113.

[0219] Of course, in other embodiments, the material of the exhaust bracket 17 and the material of the first wall 113 may be set differently.

[0220] See also Figures 3 to 9 In summary, the present application provides a specific example of a battery cell 10 based on the above embodiments. The battery cell 10 includes a housing 11 , an electrode assembly 12 , an exhaust bracket 17 and an insulating member 13 .

[0221] The housing 11 isolates the internal environment of the battery cell 10 from the external environment. The housing 11 includes a first wall 113. An explosion-proof valve 16 is disposed on the first wall 113.

[0222] The electrode assembly 12 is accommodated in the housing 11. Four electrode assemblies 12 are provided, and each electrode assembly 12 is arranged along the second direction y.

[0223] The insulating member 13 is arranged on the side of the first wall 113 facing the electrode assembly 12. The insulating member 13 has an insulating property, and the insulating member 13 insulates and isolates the first wall 113 and each electrode assembly 12. The insulating member 13 includes a main body 131 and three bosses 132. Each boss 132 is arranged at intervals along the first direction x, wherein two bosses 132 are arranged at opposite ends of the insulating member 13 along the first direction x. The main body 131 connects each boss 132 and connects the first wall 113. Two accommodating cavities 134 are arranged on the side of the insulating member 13 facing the first wall 113, and the two accommodating cavities 134 are arranged at opposite ends of the insulating member 13 along the first direction x, and are arranged at corresponding positions of the bosses 132. The end faces of the insulating member 13 at opposite ends along the first direction x are both first end faces 135. The first end face 135 is provided with four second channels 136 arranged in a staggered manner with the accommodating cavities 134. The second channels 136 are connected to the side of the insulating member 13 facing the first wall 113.

[0224] Two exhaust brackets 17 are provided, and the two exhaust brackets 17 are arranged at intervals along the first direction x and are respectively provided at opposite ends of the first wall 113 along the first direction x. The exhaust brackets 17 are welded to a side of the first wall 113 facing the electrode assembly 12 and are accommodated in the corresponding accommodation cavity 134 .

[0225] Each exhaust bracket 17 is provided with two first channels 171, the two first channels 171 are arranged at intervals along the second direction y, and both are connected along the first direction x, the two first channels 171 are arranged corresponding to two of the electrode assemblies 12, and the two first channels 171 are symmetrically distributed about the center line L of the first wall 113 along the second direction y. The first direction x intersects with the thickness direction z of the first wall 113, and the second direction y is perpendicular to the first direction x.

[0226] The exhaust bracket 17 is a metal part. The material of the exhaust bracket 17 is the same as that of the first wall 113 , both of which are aluminum. The melting point of the exhaust bracket 17 is greater than the melting point of the insulating member 13 .

[0227] The exhaust bracket 17 includes a connecting portion 172 and two supporting portions 173. The connecting portion 172 is connected to the first wall 113. The two supporting portions 173 are connected to the side of the connecting portion 172 away from the first wall 113, and are respectively arranged at opposite ends of the connecting portion 172. Each supporting portion 173 includes a first supporting wall 1731 and a second supporting wall 1732, the first supporting wall 1731 is vertically connected to the connecting portion 172, and the second supporting wall 1732 is bent and connected to one end of the first supporting wall 1731 away from the connecting portion 172. One end of each second supporting wall 1732 away from the first supporting wall 1731 is spaced apart from another second supporting wall 1732. Each supporting portion 173 and the connecting portion 172 enclose a first channel 171.

[0228] Based on the above structure, during the normal use of the battery cell 10, the first wall 113 and the electrode assembly 12 can be insulated and isolated by the unmelted insulating member 13 disposed on the side of the first wall 113 facing the electrode assembly 12, so as to reduce the risk of short circuit, current leakage and the like. In addition, the accommodating cavity 134 can be provided by the insulating member 13 to accommodate the exhaust bracket 17, so that the exhaust bracket 17 can share space with the insulating member 13 in the thickness direction z of the first wall 113, thereby reducing the additional space occupied by the exhaust bracket 17 in the thickness direction z of the first wall 113, and improving the space utilization and energy density of the battery cell 10. In addition, the strength of the corresponding area of ​​the insulating member 13 can be correspondingly enhanced by the exhaust bracket 17 to enhance the supporting effect of the corresponding area of ​​the insulating member 13 on the electrode assembly 12, thereby stabilizing the position and structure of the electrode assembly 12, reducing the relative movement or shaking of the electrode assembly 12, and reducing the risk of loosening or deformation of the electrode assembly 12.

[0229] In the early stage of thermal runaway of the battery cell 10, that is, when the battery cell 10 has thermal runaway and the insulating member 13 has not melted, the second channel 136 provided on the first end surface 135 of the insulating member 13 can promote the circulation of the internal space of the battery cell 10, so that the gas generated by the thermal runaway of the electrode assembly 12 can flow to the explosion-proof valve 16 of the first wall 113, and especially the gas generated on the side of the electrode assembly 12 can flow to the explosion-proof valve 16 of the first wall 113 through the second channel 136, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell 10, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the outer shell 11, reducing the risk of cracking of the outer shell 11 (especially the connecting seam of the outer shell 11), and improving the reliability of the battery cell 10.

[0230] In the late stage of thermal runaway of the battery cell 10, that is, when the battery cell 10 is in thermal runaway and the insulating member 13 is melted, the electrode assembly 12 can be supported by the exhaust bracket 17 exposed on the insulating member 13 to prevent the portion of the electrode assembly 12 supported by the exhaust bracket 17 from moving toward the first wall 113. Based on this, an exhaust channel flowing along the first direction x can be formed between the portion of the electrode assembly 12 supported by the exhaust bracket 17 and the first wall 113 through the first channel 171 of the exhaust bracket 17, thereby promoting the circulation of the internal space of the battery cell 10, and promoting the gas generated by the thermal runaway of the electrode assembly 12 to flow to the explosion-proof valve 16 of the first wall 113, especially promoting the gas generated at the side of the electrode assembly 12 to flow to the explosion-proof valve 16 of the first wall 113, thereby promoting the directional discharge of the gas generated by the thermal runaway of the battery cell 10, reducing the risk of gas accumulation in the small space enclosed by the side of the electrode assembly 12 and the shell 11, and reducing the risk of cracking of the shell 11 (especially the connection seam of the shell 11). In addition, each first channel 171 of the exhaust bracket 17 is also respectively arranged corresponding to an electrode assembly 12, based on which the first channel 171 can be enabled to discharge the gas generated by the thermal runaway of the electrode assembly 12 corresponding thereto in a targeted, timely and rapid manner, thereby optimizing the exhaust effect and exhaust efficiency. As a result, the risk of cracking or even explosion of the battery cell 10 (especially at the weld) can be effectively reduced, and the reliability of the battery cell 10 can be improved.

[0231] Furthermore, even if the second support wall 1732 of the exhaust bracket 17 is bent toward the connecting portion 172 relative to the first support wall 1731 under the action of impact or other external forces, the second support wall 1732, the first support wall 1731 and the connecting portion 172 can form a triangular stable structure and continue to play a supporting role. Thus, the structure and supporting effect of the exhaust bracket 17 can be optimized, so that the exhaust bracket 17 can permanently and reliably support the exhaust space between the electrode assembly 12 and the first wall 113, and the exhaust bracket 17 can permanently provide the first channel 171 between the electrode assembly 12 and the first wall 113 for the circulation of gas, which can reduce the risk of the exhaust bracket 17 being crushed by impact or other external forces and blocking the exhaust channel, thereby improving the performance and service life of the exhaust bracket 17, and optimizing the exhaust effect and exhaust efficiency.

[0232] See also Figure 2 , Figure 3 Some embodiments of the present application provide a battery 1, and the battery 1 includes a battery cell 10 provided in an embodiment of the present application.

[0233] By adopting the above solution, the battery 1 can reduce the risk of explosion of the battery 1 by applying the battery cell 10 provided in the embodiment of the present application, thereby improving the reliability and service life of the battery 1.

[0234] See also Figure 1 , Figure 3 Some embodiments of the present application provide an electrical device, which includes a battery 1 provided in an embodiment of the present application, or a battery cell 10 provided in an embodiment of the present application.

[0235] By adopting the above solution, the electrical device can improve the reliability and service life of the electrical device by applying the battery 1 or the battery cell 10 provided in the embodiment of the present application.

[0236] The above are only optional embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A battery cell, wherein: The battery cell comprises: a housing including a first wall; an electrode assembly, contained in the housing; An exhaust bracket is fixed to the side of the first wall facing the electrode assembly, and is used to support the electrode assembly in the event of thermal runaway of the battery cell. The exhaust bracket is provided with a first channel extending along a first direction, and the first direction intersects with the thickness direction of the first wall. Each of the first channels is arranged corresponding to one of the electrode assemblies.

2. The battery cell according to claim 1, wherein: There are a plurality of electrode assemblies, each of which is arranged along a second direction, and the second direction is perpendicular to the first direction; The exhaust bracket is provided with two first channels, the two first channels are arranged at intervals along the second direction, and the two first channels are arranged corresponding to two of the electrode assemblies.

3. The battery cell according to claim 2, wherein: The two first channels of the exhaust bracket are symmetrically distributed about a center line of the first wall along the second direction.

4. The battery cell according to claim 1, wherein: There are a plurality of exhaust brackets, and at least two of the exhaust brackets are arranged at intervals along the first direction.

5. The battery cell according to claim 1, wherein: There are a plurality of exhaust brackets, and at least two of the exhaust brackets are disposed at opposite ends of the first wall along the first direction.

6. The battery cell according to claim 1, wherein: The battery cell further includes an insulating member, which is disposed on a side of the first wall facing the electrode assembly and insulates and isolates the first wall and the electrode assembly. A receiving cavity is disposed on a side of the insulating member facing the first wall, and the exhaust bracket is received in the receiving cavity.

7. The battery cell according to claim 6, wherein: The insulating member includes a main body and a plurality of bosses, wherein the plurality of bosses are arranged at intervals along the first direction, the main body is connected to each of the bosses and is connected to the first wall; and the accommodating cavity is arranged on the bosses.

8. The battery cell according to claim 7, wherein: The cross-sectional area of ​​the first channel of the exhaust bracket is S1, the area of ​​the side surface of the corresponding boss along the first direction is S2, the capacity of the battery cell is C, and the mass percentage of nickel in the positive electrode active material contained in the battery cell is N; 0.125*(C / 40)*N≤S1≤0.25*S2.

9. The battery cell according to any one of claims 6 to 8, wherein: The insulating member has a first end surface along the first direction. The first end surface is provided with at least one second channel. The second channel is connected to the side surface of the insulating member facing the first wall.

10. The battery cell according to claim 9, wherein: The total occupied area of ​​each of the second channels on the first end surface is S3, the area of ​​the first end surface is S4, the capacity of the battery cell is C, and the mass percentage of nickel in the positive electrode active material contained in the battery cell is N; 0.125*(C / 10)*N≤S3≤0.5*S4.

11. The battery cell according to any one of claims 6 to 8, wherein: The melting point of the exhaust bracket is greater than the melting point of the insulating member.

12. The battery cell according to any one of claims 6 to 8, wherein: The exhaust bracket is a metal part.

13. The battery cell according to any one of claims 1 to 8, wherein: The exhaust bracket is a non-metallic part.

14. The battery cell according to any one of claims 1 to 8, wherein: The exhaust bracket includes a connecting portion and at least one supporting portion, wherein the connecting portion is connected to the first wall, and the supporting portion is connected to a side of the connecting portion facing away from the first wall.

15. The battery cell according to claim 14, wherein: There are two support parts, and the two support parts are arranged at opposite ends of the connecting part. Each support part and the connecting part enclose one first channel.

16. The battery cell according to claim 15, wherein: The supporting portion includes a first supporting wall and a second supporting wall, wherein the first supporting wall is vertically connected to the connecting portion, and the second supporting wall is bent and connected to an end of the first supporting wall away from the connecting portion.

17. The battery cell according to claim 16, wherein: One end of each of the second supporting walls away from the first supporting wall is spaced apart from another second supporting wall.

18. The battery cell according to claim 16, wherein: One end of each of the second supporting walls away from the first supporting wall is connected to another second supporting wall via a weak portion.

19. The battery cell according to any one of claims 1 to 8, wherein: The exhaust bracket is welded to the first wall.

20. The battery cell according to any one of claims 1 to 8, wherein: The exhaust bracket is made of the same material as the first wall.

21. A battery, wherein: The battery comprises the battery cell according to any one of claims 1 to 20.

22. An electrical device, wherein: The electrical device comprises the battery according to claim 21, or the battery cell according to any one of claims 1-20.

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