Battery cell, battery and electric device

Abstract

The invention provides a battery monomer, a battery and a power utilization device, the battery monomer comprises a shell used for accommodating an electrode assembly, the shell comprises a wall part, the outer surface of the wall part is provided with an accommodating groove extending along a first direction, the bottom wall of the accommodating groove is provided with a first through hole, and the first through hole is used for communicating a space in the shell with an accommodating cavity of the accommodating groove; at least part of the ventilation assembly is arranged in the containing groove, the ventilation assembly and the bottom wall of the containing groove are arranged in a spaced mode, the ventilation assembly comprises a fixing piece and a ventilation film, the fixing piece is connected with the wall part, a second through hole extending in the first direction is formed in the fixing piece, and the ventilation film comprises a covering part and a connecting part arranged around the covering part; the covering part covers the second through hole in the first direction and is used for discharging gas in the battery monomer, and the connecting part is connected with the fixing piece; and at least one part of the supporting piece is clamped between the bottom wall of the accommodating groove and the connecting part. And the battery monomer is good in sealing performance and high in reliability.

Description

Battery cells, batteries, and electrical devices 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] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the sustainable development of the automotive industry. For electric vehicles, battery technology is a key factor in their development.

[0003] In the related art, battery cells have the problem of sealing failure and leakage, which affects the reliability of the battery cells.

[0004] Summary of the Invention

[0005] An embodiment of the present application provides a battery cell, a battery, and an electrical device. The battery cell has good sealing performance and high reliability.

[0006] In the first aspect, the present application provides a battery cell, a shell for accommodating an electrode assembly, the shell including a wall portion, an outer surface of the wall portion being provided with a receiving groove extending in a first direction, a bottom wall of the receiving groove being provided with a first through hole, the first through hole being used to connect the space inside the shell with the receiving cavity of the receiving groove; a breathable component being at least partially disposed in the receiving groove and spaced apart from the bottom wall of the receiving groove, the breathable component including a fixing member and a breathable membrane, the fixing member being connected to the wall portion, the fixing member being provided with a second through hole extending in the first direction, the breathable membrane including a covering portion and a connecting portion arranged around the covering portion, the covering portion being arranged to cover the second through hole in the first direction for discharging gas inside the battery cell, the connecting portion being connected to the fixing member; a support member, at least a portion of which is clamped between the bottom wall of the receiving groove and the connecting portion.

[0007] A breathable component is provided on the wall of its shell. The breathable component includes a fixing part and a breathable membrane. A second through hole extending along a first direction is provided on the fixing part. The breathable membrane includes a covering part and a connecting part provided around the covering part. The covering part covers the second through hole provided in the first direction and is used to discharge the gas inside the battery cell. The gas inside the battery cell can flow to the covering part through the first through hole and be discharged to the outside of the battery cell through the second through hole, thereby avoiding excessive gas accumulation leading to thermal runaway of the battery cell. The connecting part is connected to the fixing part and blocks the electrolyte inside the battery cell from flowing to the outside of the battery cell through the breathable membrane. The provision of the support part can provide support to the connecting part, reduce the risk of failure of the composite interface between the connecting part and the fixing part, and ensure the tightness of the connection between the two. This reduces the probability of leakage due to sealing failure of the battery cell and improves the reliability of the battery cell.

[0008] In some embodiments, the support member is annular as a whole, is disposed around the first through hole, and is sealed and fitted with the connecting portion and the bottom wall of the accommodating groove respectively.

[0009] This arrangement allows the support member to block the path of electrolyte from the battery cell to the composite interface between the connector and the fixing member, reducing or preventing electrolyte flow to the composite interface between the connector and the fixing member, thereby ensuring a tight connection between the two. This effectively reduces the probability of leakage from battery cell seal failure and improves the reliability of the battery cell.

[0010] In some embodiments, a groove is provided on a surface of a bottom wall of the receiving tank facing the ventilation component, and the support member is partially received in the groove.

[0011] Through the above-mentioned setting, the support member can be limited by the groove, which is beneficial to the installation and positioning of the support member. Moreover, during the operation of the battery cell, the support member can be prevented from moving in the receiving groove to affect the support of the connecting part, thereby ensuring the support of the composite interface between the connecting part and the fixing member.

[0012] In some embodiments, the accommodating groove includes a first accommodating section and a second accommodating section distributed along a first direction, the first accommodating section is recessed from the outer surface of the wall portion, the radial dimension of the first accommodating section is larger than the maximum radial dimension of the second accommodating section, a first step surface is connected between the side wall surface of the first accommodating section and the side wall surface of the second accommodating section, the fixing member is at least partially located in the first accommodating section and supported on the first step surface, and at least part of the breathable membrane and / or at least part of the support member is arranged in the second accommodating section.

[0013] By adopting the above-mentioned structure of the receiving groove, the first step surface can provide support for the fixing member in the first direction, ensuring the support and positioning of the fixing member and the connection between the fixing member and the wall. At the same time, the first and second receiving sections can accommodate and protect the various components of the ventilation assembly.

[0014] In some embodiments, along the first direction, the depth of the first accommodating section is H1, and the thickness of the fixing member is T, wherein 0.3≤H1 / T≤2.5.

[0015] By setting the value range of H1 / T to 0.3 to 2.5, the first accommodating section can not only limit the fixing part, but also make the thickness of the fixing part in the first direction moderate. When connected with the wall portion, it can not only ensure the connection area between the side wall of the first accommodating section, but also reduce the size of the fixing part protruding from the first accommodating section in the first direction, thereby ensuring the assembly and connection effect of the fixing part in the accommodating groove.

[0016] In some embodiments, 1≤H1 / T≤2.5.

[0017] By ensuring that 1≤H1 / T≤2.5, the fixing part can be positioned entirely within the first accommodating section, thereby ensuring connection with the side wall of the first accommodating section. At the same time, the fixing part does not protrude from the wall, thereby ensuring smooth assembly without interfering with the installation of the battery cell gas component.

[0018] In some embodiments, the second containment section includes a first sub-containment section and a second sub-containment section distributed along the first direction, the radial dimension of the first sub-containment section is larger than the radial dimension of the second sub-containment section and smaller than the radial dimension of the first containment section, a first step surface is connected between the side wall surface of the first sub-containment section and the side wall surface of the first containment section, at least part of the breathable membrane is located in the first sub-containment section, and at least part of the support member is located in the second sub-containment section.

[0019] Through the above arrangement, the accommodating groove can be in the form of a stepped groove with gradually decreasing radial dimensions, which can not only ensure the accommodating requirements for the fixing part, breathable membrane and support part, but also ensure the installation and limiting requirements of the three.

[0020] In some embodiments, along the first direction, the depth of the first sub-containing section is H2, and the thickness of the breathable membrane is M, wherein 0≤H2-M≤0.7 mm.

[0021] By ensuring that 0≤H2-M≤0.7 mm, interference between the breathable membrane and the first sub-accommodating section during assembly can be prevented, thereby ensuring connection between the fixing member and the wall portion.

[0022] In some embodiments, along the first direction, the depth of the second sub-accommodating section is H3, and the thickness of the support member is Q, wherein 0.1≤H3 / Q≤0.95.

[0023] By ensuring that 0.1≤H3 / Q≤0.95, the support member can be in a compressed state when installed between the bottom wall and the connecting portion, ensuring close contact with the bottom wall and the connecting portion, achieving isolation of the electrolyte, and improving the sealing of the battery cell.

[0024] In some embodiments, along the radial direction of the first through hole, there is a gap between the support member and the side wall of the second sub-accommodating section.

[0025] Through the above arrangement, when the fixing member is connected to the wall by welding or other means, the heat generated by welding will not affect the supporting member. Moreover, when the supporting member adopts an elastic sealing ring, the above arrangement can also leave compression deformation space for the elastic sealing ring to ensure the sealing effect.

[0026] In some embodiments, along the radial direction of the first through hole, the outer diameter of the second sub-accommodating section is D1, and the outer diameter of the supporting member is D2, wherein 0.2≤D2 / D1≤0.95.

[0027] In some embodiments, the support member includes an elastic sealing ring that is compressed in a first direction and clamped between the connecting portion and the bottom wall of the accommodating groove.

[0028] By providing the support member with an elastic sealing ring, and by compressing the elastic sealing ring in the first direction and clamping it between the connecting portion and the bottom wall of the receiving groove, a compressive force can be applied in the first direction to the composite interface between the connecting portion and the fixing member. This not only provides support for the connecting portion, but also prevents separation between the connecting portion and the fixing member at the composite interface, thereby ensuring sealing. Furthermore, this arrangement ensures a sealed fit between the elastic sealing ring, the bottom wall of the receiving groove, and the connecting portion, allowing the elastic sealing ring to block the path of electrolyte within the battery cell from flowing to the composite interface between the connecting portion and the fixing member, reducing or preventing electrolyte flow to the composite interface between the connecting portion and the fixing member, and effectively ensuring a tight connection between the two.

[0029] In some embodiments, the number of the elastic sealing rings is more than two, and the more than two elastic sealing rings are coaxially arranged and distributed along the radial direction of the first through hole.

[0030] By making the number of elastic sealing rings more than two, more than two elastic sealing rings can provide multiple barrier protections, effectively blocking the path for the electrolyte inside the battery cell to flow to the connection composite interface between the connecting part and the fixing part, reducing or avoiding the flow of electrolyte to the connection composite interface between the connecting part and the fixing part.

[0031] In some embodiments, along the first direction, the orthographic projection of the elastic sealing ring is in the shape of a circular ring, an elliptical ring, or a polygonal ring.

[0032] By making the positive projection of the elastic sealing ring in the first direction into a circular ring, an elliptical ring or a polygonal ring, it is possible to ensure the support of the connecting part and the fixing part at various locations in the circumference of the first through hole. At the same time, it is possible to ensure the surrounding requirements of the first through hole and block the path of the electrolyte inside the battery cell to flow to the connection composite interface between the connecting part and the fixing part.

[0033] In some embodiments, there are multiple second through holes, which are spaced apart and distributed on the fixing member.

[0034] By ensuring that there are two or more second through-holes, exhaust requirements can be met. At the same time, the size of each second through-hole can be moderate, preventing an excessively large diameter from affecting the strength of the fixing, and preventing an excessively small diameter from affecting ventilation efficiency. Furthermore, the area between two adjacent second through-holes can be attached to a breathable membrane. When gas from the battery cell acts on the breathable membrane during discharge through the membrane to the exterior of the battery cell, the fixing can provide a force opposite to the internal pressure of the battery cell to the membrane in the area between the two adjacent second through-holes, reducing deformation of the breathable membrane, improving the overall internal pressure resistance of the breathable assembly, and thereby improving the reliability of the battery cell.

[0035] In some embodiments, the diameter of the second through hole ranges from 0.5 mm to 3 mm.

[0036] By setting the diameter of the second through hole to a value range of 0.5mm-3mm, the exhaust requirements of the second through hole can be guaranteed, which is conducive to setting the number of second through holes to more than two, and the strength of the fixing part can also be guaranteed, thereby improving the ventilation efficiency of the second through hole.

[0037] In some embodiments, there is one second through hole, and along the radial direction of the first through hole, the minimum vertical distance between the outer edge of the breathable membrane and the hole wall of the second through hole is N, and the value range of N is 1mm-6mm; or, there are multiple second through holes, and along the radial direction of the first through hole, there are multiple minimum vertical distances between the outer edge of the breathable membrane and the hole walls of the multiple second through holes, the minimum value of the multiple minimum vertical distances is N, and the value range of N is 1mm-6mm.

[0038] With the above arrangement, no matter one or more breathable membranes are used, the distance between the hole wall of the second through hole and the edge of the breathable membrane can be moderate, thereby ensuring the bonding strength between the breathable membrane and the fixing member and ensuring the ventilation effect.

[0039] In some embodiments, along the radial direction of the first through hole, a first vertical distance between an outer edge of the breathable membrane and an outer edge of the fixing member is d, and a value range of d is 1 mm-5 mm.

[0040] By setting the value range of d to 1mm-5mm, the value of d can be made moderate, which is beneficial for preventing the residual heat of laser welding from melting the breathable membrane when the fixing part is connected to the wall by welding or other methods. At the same time, it can also avoid the value of d being too large, ensuring the number of breathable holes and thus ensuring the breathable effect.

[0041] In some embodiments, the housing includes a shell and an end cover assembly, the shell has an opening, the end cover assembly is arranged to close the opening, and one of the shell and the end cover assembly includes a wall portion.

[0042] In a second aspect, the present application provides a battery comprising the above-mentioned battery cell.

[0043] In a third aspect, the present application provides an electrical device comprising the above-mentioned battery, which is used to provide electrical energy.

[0044] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0046] FIG1 is a schematic structural diagram of a vehicle provided in one embodiment of the present application;

[0047] FIG2 is a schematic structural diagram of a battery pack provided in one embodiment of the present application;

[0048] FIG3 is a schematic diagram of the exploded structure of a battery cell provided in one embodiment of the present application;

[0049] FIG4 is a schematic diagram of a partial structure of a battery cell provided in one embodiment of the present application;

[0050] FIG5 is a cross-sectional view taken along the AA direction in FIG4 ;

[0051] FIG6 is a partial enlarged view of point B in FIG5 ;

[0052] FIG7 is a partial exploded view of a battery cell provided in one embodiment of the present application;

[0053] FIG8 is a partial cross-sectional view of a battery cell provided in another embodiment of the present application;

[0054] FIG9 is a partially enlarged view of a battery cell provided in yet another embodiment of the present application.

[0055] Reference numerals in the specific embodiments are as follows: 1000 - vehicle; 100 - battery; 200 - controller; 300 - motor; 10 - housing; 11 - first portion; 12 - second portion; 20 - battery cell; 201 - housing; 21 - casing; 22 - electrode assembly; 221 - positive electrode tab; 222 - negative electrode tab; 23 - end cap assembly; 231 - wall portion; 232 - receiving groove; 2321 - bottom wall; 2321a - first through hole; 2321b - groove; 2322 - first receiving section; 2323 - second receiving section; 2323a - first sub-receiving section; 2323b - second sub-receiving section; 2324 - first step surface; 233 - cover plate; 234 - insulating member; 235 - first electrode terminal; 236 - second electrode terminal; 24 - Breathable assembly; 241 - Fixing member; 2411 - Second through hole; 242 - Breathable membrane; 2421 - Covering portion; 2422 - Connecting portion; 25 - Support member; 251 - Elastic sealing ring; 235 - Positive electrode terminal; 236 - Negative electrode terminal; X - First direction; Y - Radial direction. DETAILED DESCRIPTION

[0056] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0057] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in an embodiment of the present application should have the common meanings understood by technicians in the field to which an embodiment of the present application belongs.

[0058] In the description of one embodiment of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", 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 one embodiment of 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 cannot be understood as a limitation on one embodiment of the present application.

[0059] In addition, the technical terms "first," "second," etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly indicate the number of the technical features indicated. In the description of an embodiment of the present application, the meaning of "plurality" is more than two, unless otherwise specifically defined.

[0060] In the description of an embodiment of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in an embodiment of the present application based on the specific circumstances.

[0061] In the description of one embodiment of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0062] Currently, market developments indicate that power batteries are becoming increasingly widely used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As power battery applications continue to expand, market demand is also growing.

[0063] In related technologies, in order to prevent thermal runaway of battery cells, a corresponding vent assembly is provided on the battery cells. During the long-term use and cycling of the battery cells, the composite interfaces between the components of the vent assembly may fail, resulting in failure of the battery cell seal and leakage, thus affecting the reliability of the battery cell.

[0064] In order to alleviate the problem of battery cell leakage due to seal failure, a support member can be provided to support the corresponding components in the vent assembly, thereby reducing the risk of composite interface failure between the components of the vent assembly and thereby improving the reliability of the battery cell.

[0065] Based on the above considerations, in order to alleviate the problem of leakage caused by seal failure in battery cells, a battery cell is designed, which includes a shell, a vent assembly, and a support member. The shell is used to accommodate the electrode assembly, and includes a wall portion. The outer surface of the wall portion is provided with a receiving groove extending in a first direction. The bottom wall of the receiving groove is provided with a first through hole. The first through hole is used to connect the space inside the shell with the receiving cavity of the receiving groove; the vent assembly is at least partially disposed in the receiving groove and spaced apart from the bottom wall of the receiving groove. The vent assembly includes a fixing member and a vent membrane. The fixing member is connected to the wall portion. The fixing member is provided with a second through hole extending in the first direction. The vent membrane includes a covering portion and a connecting portion provided around the covering portion. The covering portion is provided in the first direction to cover the second through hole and is used to discharge gas inside the battery cell. The connecting portion is connected to the fixing member; the support member is at least partially clamped between the bottom wall of the receiving groove and the connecting portion.

[0066] In such a battery cell, since a support member is provided and at least a portion of the support member is clamped between the bottom wall of the accommodating groove and the connecting portion, the support member can provide supporting force to the connecting portion, thereby preventing the connecting portion from separating from the fixing member, alleviating the problem of battery cell sealing failure and leakage, and improving the reliability of the battery cell.

[0067] The technical solution described in one embodiment of the present application is applicable to batteries and electrical devices using batteries.

[0068] Electrical devices may include vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may include fuel vehicles, gas vehicles, or new energy vehicles. New energy vehicles may include pure electric vehicles, hybrid vehicles, or extended-range vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. 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, etc. One embodiment of the present application does not impose any special restrictions on the above-mentioned electrical devices.

[0069] It should be understood that the technical solution described in one embodiment of the present application is not limited to the batteries and electrical equipment described above, but can also be applied to all batteries including boxes and electrical equipment using batteries. However, for the sake of simplicity, the following embodiments are explained using electric vehicles as an example.

[0070] Please refer to FIG1 , which is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of the present application. A battery 100 is disposed inside the vehicle 1000. The battery 100 can be disposed at the bottom, head, or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000.

[0071] The vehicle 1000 may further include a controller 200 and a motor 300 . The controller 200 is used to control the battery 100 to supply power to the motor 300 , for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0072] In some embodiments of the present application, the battery 100 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0073] Please refer to FIG. 2 , which is a schematic structural diagram of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 20 . The housing 10 is used to accommodate the battery cell 20 .

[0074] The housing 10 is a component that houses the battery cells 20, providing a storage space for the battery cells 20. The housing 10 can have various structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap to define a storage space for the battery cells 20. The first portion 11 and the second portion 12 can have various shapes, such as a rectangular parallelepiped or a cylinder. The first portion 11 can be a hollow structure with one side open, and the second portion 12 can also be a hollow structure with one side open. The open side of the second portion 12 overlaps the open side of the first portion 11, forming the housing 10 with a storage space. Alternatively, the first portion 11 can be a hollow structure with one side open, and the second portion 12 can be a plate-like structure. The second portion 12 overlaps the open side of the first portion 11, forming the housing 10 with a storage space. The first portion 11 and the second portion 12 can be sealed by a sealing element, such as a sealing ring, sealant, etc.

[0075] In the battery 100, there can be one or more battery cells 20. If there are multiple battery cells 20, the multiple battery cells 20 can be connected in series, parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. Multiple battery cells 20 can be connected in series, parallel, or in a hybrid connection to form a battery module, which is then connected in series, parallel, or in a hybrid connection to form a whole and housed within the housing 10. Alternatively, all battery cells 20 can be directly connected in series, parallel, or in a hybrid connection, and then the whole battery module can be housed within the housing 10.

[0076] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 can be cylindrical, flat, rectangular, or in other shapes. A battery cell 20 is the smallest unit that makes up a battery.

[0077] As shown in Figure 3, please further refer to Figures 3 to 7. Figure 4 is a schematic diagram of the local structure of a battery cell provided in an embodiment of the present application, Figure 5 is a cross-sectional view along the AA direction in Figure 4, Figure 6 is a local enlarged view of point B in Figure 5, and Figure 7 is a local exploded view of a battery cell provided in an embodiment of the present application.

[0078] An embodiment of the present application provides a battery cell 20, including a shell 201, an electrode assembly 22, a breathable assembly 24 and a support member 25. The shell 201 is used to accommodate the electrode assembly 22. The shell 201 includes a wall portion 231. The outer surface of the wall portion 231 is provided with a receiving groove 232 extending along a first direction X. A first through hole 2321a is provided on the bottom wall 2321 of the receiving groove 232. The first through hole 2321a is used to connect the space inside the shell 201 with the receiving cavity of the receiving groove 232. The vent assembly 24 is at least partially disposed within the receiving groove 232 and spaced apart from the bottom wall 2321 of the receiving groove 232. The vent assembly 24 includes a fixing member 241 and a vent membrane 242. The fixing member 241 is connected to the wall portion and is provided with a second through hole 2411 extending in the first direction X. The vent membrane 242 includes a covering portion 2421 and a connecting portion 2422 disposed around the covering portion 2421. The covering portion 2421 is disposed in the first direction X to cover the second through hole 2411 and is used to discharge gas from the battery cell 20. The connecting portion 2422 is connected to the fixing member 241. At least a portion of the support member 25 is clamped between the bottom wall 2321 of the receiving groove 232 and the connecting portion 2422.

[0079] The housing 201 may include a shell 21 and an end cap assembly 23. Optionally, the shell 21 and the end cap assembly 23 may be an integral structure. Of course, in some embodiments, the shell 21 and the end cap assembly 23 may be separate bodies, with the shell 21 having an opening and the end cap assembly 23 enclosing the opening.

[0080] The end cover assembly 23 can generally include a cover plate 233, which can be set to close the opening of the shell 21. The wall portion 231 of the outer shell 201 can include at least one of the side wall and the bottom wall of the shell 21, and can also include the cover plate 233 of the end cover assembly 23.

[0081] Optionally, the end cap assembly 23 may further include an insulating member 234, which may be used to isolate the electrode assembly 22 and the cover plate 233 in the housing 21 to reduce the risk of short circuit. For example, the insulating member 234 may include plastic, rubber, or the like.

[0082] Optionally, the end cap assembly 23 may further include an electrode terminal, which is used to electrically connect to the electrode assembly 22. The end cap assembly 23 may include one electrode terminal. If there is one electrode terminal, the electrode terminal is disposed on the cover plate 233. The electrode terminal may be one of a first electrode terminal 235 and a second electrode terminal 236. Optionally, the electrode terminal may be disposed in the center of the cover plate 233, or may be disposed offset from the center of the cover plate 233. Optionally, the end cap assembly 23 may include two electrode terminals. If there are two electrode terminals, the two electrode terminals may include a first electrode terminal 235 and a second electrode terminal 236. The first electrode terminal 235 and the second electrode terminal 236 may be disposed on the cover plate 233.

[0083] The electrode assembly 22 is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies 22 may be contained in the housing 21. The electrode assembly 22 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive electrode tab 221 and the negative electrode tab 222 may be located together at one end of the main body or respectively at both ends of the main body. The positive electrode tab 221 may be connected to one of the first electrode terminal 235 and the second electrode terminal 236, and the negative electrode tab 222 may be connected to the other of the first electrode terminal 235 and the second electrode terminal 236. During the charge and discharge process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte.

[0084] Along the first direction X, the depth of the accommodating groove 232 is less than the thickness of the wall portion 231 , and the bottom wall 2321 can be understood as the bottom area of ​​the accommodating groove 232 in the first direction X.

[0085] The first through hole 2321 a may be provided through the bottom wall 2321 of the receiving groove 232 along the first direction X. The shape of the first through hole 2321 a may be circular, elliptical, polygonal, or the like.

[0086] The breathable component 24 may be partially located in the receiving groove 232 , or may be completely located in the receiving groove 232 .

[0087] The fixing member 241 can be a component mounted on the wall portion 231. For example, the fixing member 241 can include a plate-like structure mounted on the wall portion 231. When the plate-like structure is provided, a second through hole 2411 can be provided above the plate-like structure. Of course, the fixing member 241 can also be an annular structure to ensure the circulation of gas.

[0088] The number of second through holes 2411 provided on the fixing member 241 can be one, or two or more. When there are two or more second through holes 2411, the two or more second through holes 2411 can be spaced apart. The two or more second through holes 2411 can be arranged in rows and columns, or in an array, or can be distributed sequentially along a circular trajectory, or can be distributed sequentially along a straight or curved trajectory. When there are two or more second through holes 2411, the breathable membrane 242 layer 2322 covers each second through hole 2411 in the first direction XX.

[0089] The shape of the second through hole 2411 can be circular, elliptical, or oval.

[0090] The breathable membrane 242 is ventilated and can be made of materials such as PP (polypropylene), PE (polyethylene), and PU (polyurethane). Gas within the battery cell 20 must pass through the breathable membrane 242 to be exhausted. The breathable membrane 242 allows gas within the battery cell 20 to flow to the outside while preventing moisture and other substances from entering the battery cell 20.

[0091] The covering portion 2421 has a breathable function and can be made of a breathable material. The connecting portion 2422 can also have a breathable function and can be made of a breathable material. Of course, the connecting portion 2422 can also not have a breathable function, that is, it can also be made of a non-breathable material.

[0092] The covering portion 2421 may be located on the inner side of the connecting portion 2422. The connecting portion 2422 is in a full ring shape and is arranged around the covering portion 2421. The two may be an integral structure. Of course, they may also be made of separate parts and connected into an integral structure.

[0093] When the number of the second through holes 2411 is two or more, the orthographic projection of the covering portion 2421 in the first direction X covers each of the second through holes 2411 .

[0094] The connection portion 2422 of the breathable membrane 242 can be connected to the fixing member 241 by bonding, chemical bonding, or the like.

[0095] The support member 25 can be an annular structure disposed around the first through hole 2321a, or can include multiple support members, which can be spaced apart or spliced ​​together in sequence.

[0096] In an optional embodiment of the present application, a battery cell is provided with a vent assembly 24 disposed on the wall portion 231 of its housing 201. The vent assembly 24 includes a fixing member 241 and a vent membrane 242. The fixing member 241 is provided with a second through hole 2411 extending along a first direction X. The vent membrane 242 includes a covering portion 2421 and a connecting portion 2422 disposed around the covering portion 2421. The covering portion 2421 is disposed in the first direction X to cover the second through hole 2411 and to discharge gas from within the battery cell 20. Gas from within the battery cell 20 can flow through the first through hole 2321a to the covering portion 2421 and then be discharged to the exterior of the battery cell 20 through the second through hole 2411, thereby preventing thermal runaway of the battery cell 20 caused by excessive gas accumulation. The connecting portion 2422 is connected to the fixing member 241 and, through the vent membrane 242, blocks the flow of electrolyte from the battery cell 20 to the exterior of the battery cell 20. The support member 25 provides support to the connection portion 2422, reducing the risk of failure at the interface between the connection portion 2422 and the fixing member 241, and ensuring a tight connection between the two. This in turn reduces the probability of leakage due to seal failure in the battery cell 20 and improves the reliability of the battery cell 20.

[0097] In some embodiments, the support member 25 is annular as a whole, is disposed around the first through hole 2321 a , and is sealed and fitted with the connecting portion 2422 and the bottom wall 2321 of the receiving groove 232 , respectively.

[0098] The support member 25 may be in the shape of a closed circular ring, an elliptical ring, or a polygonal ring. Along the first direction X, the orthographic projection of the first through hole 2321 a is located inside the support member 25 .

[0099] The support member 25 can achieve a sealed fit by closely contacting the connecting portion 2422 and the bottom wall 2321 of the receiving groove 232. For example, the support member 25 can be made of an elastic structure, and closely contacting the support member 25 by being squeezed in the first direction X, thereby ensuring a sealed fit. Of course, the support member 25 can also achieve a sealed fit by being adhesively connected to the connecting portion 2422 and the bottom wall 2321 of the receiving groove 232.

[0100] This arrangement allows the support member 25 to block the path of electrolyte within the battery cell 20 from flowing toward the interface between the connecting portion 2422 and the fixing member 241, reducing or preventing electrolyte from flowing there and ensuring a tight connection between the two. This effectively reduces the probability of leakage due to seal failure in the battery cell 20 and improves the reliability of the battery cell 20.

[0101] In some optional embodiments, a groove 2321 b is provided on a surface of the bottom wall 2321 of the accommodating groove 232 facing the breathable component 24 , and the supporting member 25 is partially accommodated in the groove 2321 b .

[0102] The shape of the groove 2321b can match the bottom shape of the support member 25. When the support member 25 is in a full ring shape, the groove 2321b can be an annular groove. When the support member 25 includes multiple support bodies, the groove 2321b can be an annular groove, or it can be a plurality of groove bodies arranged corresponding to each support body.

[0103] Through the above-mentioned setting, the support member 25 can be limited by the groove 2321b, which is beneficial to the installation and positioning of the support member 25. Moreover, during the operation of the battery cell 20, the support member 25 can be prevented from moving in the receiving groove 232 to affect the support of the connecting part 2422, thereby ensuring the support of the composite interface between the connecting part 2422 and the fixing member 241.

[0104] Referring to FIG. 3 to FIG. 7 , in some optional embodiments, the support member 25 includes an elastic sealing ring 251 , which is compressed in the first direction X and clamped between the connecting portion 2422 and the bottom wall 2321 of the receiving groove 232 .

[0105] The number of elastic sealing rings 251 included in the support member 25 can be one or more than two. When there are more than two, the radial Y dimensions of the more than two elastic sealing rings 251 can gradually increase, and the more than two elastic sealing rings 251 can be distributed along the radial Y of the first through hole 2321a.

[0106] The elastic sealing ring 251 is disposed around the first through hole 2321 a.

[0107] When the bottom wall 2321 of the accommodating groove 232 includes a groove 2321b, each elastic sealing ring 251 may be provided with a groove 2321b, and a side portion of the elastic sealing ring 251 in the first direction X may be snapped into the corresponding groove 2321b.

[0108] By providing the support member 25 with an elastic sealing ring 251, and by compressing and clamping the elastic sealing ring 251 between the connecting portion 2422 and the bottom wall 2321 of the receiving groove 232 in the first direction X, a compressive force can be applied to the interface between the connecting portion 2422 and the fixing member 241 in the first direction X. This not only provides support for the connecting portion 2422, but also prevents separation between the connecting portion 2422 and the fixing member 241 at the interface, thereby ensuring a tight seal. Furthermore, this arrangement ensures a sealed fit between the elastic sealing ring 251, the bottom wall 2321 of the receiving groove 232, and the connecting portion 2422, allowing the support member 25 to block the path of electrolyte within the battery cell 20 from flowing to the interface between the connecting portion 2422 and the fixing member 241, thereby reducing or preventing electrolyte flow to the interface between the connecting portion 2422 and the fixing member 241, and effectively ensuring a tight connection between the two.

[0109] As shown in FIG. 8 , in some optional embodiments, the number of the elastic sealing rings 251 is more than two, and the more than two elastic sealing rings 251 are coaxially arranged and distributed along the radial direction Y of the first through hole 2321 a .

[0110] The number of the elastic sealing rings 251 can be two, three or more, and can be specifically set according to the remaining space of the accommodating groove 232 and the connection composite area between the connecting portion 2422 and the fixing member 241 .

[0111] The two or more elastic sealing rings 251 can be arranged successively in the radial direction Y of the first through hole 2321a, or can be arranged at intervals, and the interval arrangement can be selected.

[0112] By making the number of elastic sealing rings 251 more than two, more than two elastic sealing rings 251 can provide multiple blocking protections, effectively blocking the path of the electrolyte inside the battery cell 20 to flow to the connection composite interface between the connecting part 2422 and the fixing part 241, reducing or avoiding the flow of electrolyte to the connection composite interface between the connecting part 2422 and the fixing part 241, and ensuring the reliability of the connection composite interface.

[0113] In some optional embodiments, along the first direction X, the orthographic projection of the elastic sealing ring 251 is in the shape of a circular ring, an elliptical ring, or a polygonal ring.

[0114] Along the first direction X, the orthographic projection of the elastic sealing ring 251 can be a circular ring, an elliptical ring, or a polygonal ring.

[0115] By making the positive projection of the elastic sealing ring 251 in the first direction X into a circular ring, an elliptical ring or a polygonal ring, the support effect on the connecting portion 2422 and the fixing member 241 at various locations in the circumferential direction of the first through hole 2321a can be guaranteed. At the same time, the surrounding requirements for the first through hole 2321a can be guaranteed, blocking the path for the electrolyte inside the battery cell 20 to flow to the connection composite interface between the connecting portion 2422 and the fixing member 241.

[0116] Please refer to Figures 3 to 8. In some optional embodiments, the accommodating groove 232 includes a first accommodating section 2322 and a second accommodating section 2323 distributed along the first direction X. The first accommodating section 2322 is recessed from the outer surface of the wall portion 231. The radial dimension of the first accommodating section 2322 is greater than the maximum radial dimension of the second accommodating section 2323. A first step surface 2324 is connected between the side wall surface of the first accommodating section 2322 and the side wall surface of the second accommodating section 2323. The fixing member 241 is at least partially located in the first accommodating section 2322 and supported on the first step surface 2324. At least a portion of the breathable membrane 242 and / or at least a portion of the support member 25 is arranged in the second accommodating section 2323.

[0117] The radial dimension of the first accommodating section 2322 may be greater than the radial dimension of each portion of the second accommodating section 2323 .

[0118] Along the first direction X, the radial dimension of the second accommodating section 2323 can remain unchanged, that is, the second accommodating section 2323 can adopt a hole with a constant cross-section. Of course, along the first direction X, the radial dimension of the second accommodating section 2323 can also change, that is, the second accommodating section 2323 can also adopt a stepped hole shape.

[0119] At least part or all of the breathable membrane 242 can be located in the second accommodating section 2323, and at least part or all of the support member 25 can be located in the second accommodating section 2323. Of course, at least part or all of the support member 25 and at least part or all of the breathable membrane 242 can also be located in the second accommodating section 2323.

[0120] By adopting the above-described structure of the receiving groove 232, the first stepped surface 2324 can provide support for the fixing member 241 in the first direction X, ensuring the support and positioning of the fixing member 241 and the connection between the fixing member 241 and the wall portion 231. At the same time, the first receiving section 2322 and the second receiving section 2323 can accommodate and protect the various components of the breathable assembly 24.

[0121] In some embodiments, along the first direction X, the depth of the first accommodating section 2322 is H1, and the thickness of the fixing member 241 is T, wherein 0.3≤H1 / T≤2.5.

[0122] The thickness of the fixing member 241 is the maximum thickness of the fixing member 241 in the first direction X. Optionally, the fixing member 241 may be a plate-shaped structure.

[0123] The ratio H1 / T of the depth of the first accommodating section 2322 to the thickness of the fixing member 241 can be any value between 0.3 and 2.5, including the two extreme values ​​of 0.3 and 2.5. H1 / T can be any value between 0.5 and 2. Some optional examples include 0.8, 1, 1.3, 1.5, 1.7, 1.9, etc.

[0124] By setting the value range of H1 / T to 0.3 to 2.5, the first accommodating section 2322 can not only limit the fixing part 241, but also make the thickness of the fixing part 241 in the first direction X moderate. When connected with the wall portion 231, it can not only ensure the connection area between the side wall of the first accommodating section 2322, but also reduce the size of the fixing part 241 protruding from the first accommodating section 2322 in the first direction X, thereby ensuring the assembly and connection effect of the fixing part 241 in the accommodating groove 232.

[0125] In some optional embodiments, a ratio H1 / T of the depth H1 of the first accommodating section 2322 to the thickness T1 of the fixing member 241 may be in the range of 1≤H1 / T≤2.5.

[0126] The value range of H1 / T can be any value between 1 and 2.5, including the two end values ​​of 1 and 2.5. It can be optionally 1.2≤H1 / T≤2. In some optional embodiments, the value of H1 / T can be 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, etc.

[0127] By ensuring that 1≤H1 / T≤2.5, the fixing member 241 can be ensured to be located entirely in the first accommodating section 2322, thereby ensuring the connection requirements with the side wall of the first accommodating section 2322. At the same time, the fixing member 241 can be prevented from protruding from the wall portion 231, thereby ensuring smooth assembly and not interfering with the installation of the gas components of the battery cell 20.

[0128] In some optional embodiments, the second accommodating section 2323 includes a first sub-accommodating section 2323a and a second sub-accommodating section 2323b distributed along the first direction X, the radial dimension of the first sub-accommodating section 2323a is larger than the radial dimension of the second sub-accommodating section 2323b and smaller than the radial dimension of the first accommodating section 2322, and a first step surface 2324 is connected between the side wall surface of the first sub-accommodating section 2323a and the side wall surface of the first accommodating section 2322, at least a portion of the breathable membrane 242 is located in the first sub-accommodating section 2323a, and at least a portion of the support member 25 is located in the second sub-accommodating section 2323b.

[0129] Along the first direction X, the first sub-accommodating section 2323a is located between the first accommodating section 2322 and the second sub-accommodating section 2323b. Along the first direction X, the accommodating groove 232 may be in the form of a stepped groove with a radial dimension gradually decreasing.

[0130] The battery cell 20 provided in the embodiment of the present application, through the above-mentioned configuration, can accommodate the fixing member 241 by using the first accommodating section 2322, accommodate the breathable membrane 242 by using the first sub-accommodating section 2323a, and accommodate at least part of the support member 25 by using the second sub-accommodating section 2323b.

[0131] Through the above arrangement, the accommodating groove 232 can be in the form of a stepped groove with gradually decreasing radial dimensions, which can not only ensure the accommodation requirements for the fixing member 241, the breathable membrane 242 and the support member 25, but also ensure the installation and limiting requirements of the three.

[0132] In some optional embodiments, along the first direction X, the depth of the first sub-accommodating section 2323a is H2, and the thickness of the breathable membrane 242 is M, wherein 0≤H2-M≤0.7 mm.

[0133] The difference H2-M between the depth H2 of the first sub-accommodating section 2323a and the thickness M of the breathable membrane 242 can be any value between 0 and 0.7, including 0 and 0.7 mm. H2-M can be any value between 0 and 0.5. In some embodiments, H2-M can be 0.1 mm, 0.2 mm, 0.3 mm, or 0.4 mm.

[0134] By ensuring that 0≤H2-M≤0.7 mm, interference between the breathable membrane 242 and the first sub-accommodating section 2323 a can be prevented during assembly, thereby ensuring the connection between the fixing member 241 and the wall portion 231 .

[0135] In some optional embodiments, along the first direction X, the depth of the second sub-accommodating section 2323 b is H3, and the thickness of the support member 25 is Q, wherein 0.1≤H3 / Q≤0.95.

[0136] The ratio H3 / Q of the depth H3 of the second sub-accommodating section 2323b to the thickness Q of the support member 25 can be any value in the range of 0.1 to 0.95, including the two end values ​​of 0.1 and 0.95. In some optional embodiments, the range of H3 / Q can be any value in the range of 0.2 to 0.95, and H3 / Q can be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0137] When the support member 25 is an elastic sealing ring 251, the thickness Q of the support member 25 is the thickness of the support member 25 in a free state. In other words, when the support member 25 includes the elastic sealing ring 251, the thickness of the support member 25 can be understood as the thickness of the elastic sealing ring 251 in the first direction X when it is not subjected to external force, i.e., not compressed.

[0138] By ensuring that 0.1≤H3 / Q≤0.95, the support member 25 can be in a compressed state when installed between the bottom wall 2321 and the connecting portion 2422, ensuring close contact with the bottom wall 2321 and the connecting portion 2422, achieving isolation of the electrolyte, and improving the sealing of the battery cell 20.

[0139] In some embodiments, along the radial direction Y of the first through hole 2321 a , there is a gap between the support member 25 and the sidewall of the second sub-accommodating section 2323 b .

[0140] With the above arrangement, when the fixing member 241 is connected to the wall portion 231 by welding or other methods, the heat generated by the welding will not affect the support member 25. Furthermore, when the support member 25 adopts the elastic sealing ring 251, the above arrangement can also leave space for the elastic sealing ring 251 to compress and deform, thereby ensuring a good sealing effect.

[0141] In some embodiments, along the radial direction Y of the first through hole 2321 a , the outer diameter of the second sub-accommodating section 2323 b is D1 , and the outer diameter of the support member 25 is D2 , wherein 0.2≤D2 / D1≤0.95.

[0142] The outer diameter of the support member 25 can be understood as the vertical distance between the outermost surface of the support member 25 and its center. For example, when the support member 25 includes a single elastic sealing ring 251, the outer diameter of the support member 25 can be understood as the vertical distance between the outermost surface of the elastic sealing ring 251 and its center. When the support member 25 includes two or more elastic sealing rings 251, the outer diameter of the support member 25 can be understood as the vertical distance between the outermost surface of the outermost elastic sealing ring 251 and its center.

[0143] The ratio D2 / D1 between the outer diameter D2 of the support member 25 and the outer diameter D1 of the second sub-containing section 2323b can be any value between 0.2 and 0.95, including the two end values ​​of 0.2 and 0.95, and can be any value between 0.3 and 0.95. For example, it can be 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0144] By ensuring that 0.2≤D2 / D1≤0.95, it is effectively ensured that when the fixing member 241 is connected to the wall portion 231 by welding or other means, the heat generated by the welding will not affect the support member 25. Furthermore, when the support member 25 uses the elastic sealing ring 251, the above arrangement is conducive to leaving space for the elastic sealing ring 251 to compress and deform, thereby ensuring a good sealing effect.

[0145] The number of the second through hole 2411 provided on the fixing member 241 may be one.

[0146] Of course, in some optional embodiments, the number of the second through holes 2411 can be multiple and distributed at intervals on the fixing member 241 .

[0147] Of course, there can be more than two second through holes 2411. When there are more than two, the two or more second through holes 2411 can be spaced apart. The two or more second through holes 2411 can be arranged in rows and columns or in an array, or can be distributed sequentially along a circular trajectory, or can be distributed sequentially along a straight or curved trajectory. When there are more than two second through holes 2411, the breathable membrane 242 covers each second through hole 2411 in the first direction X.

[0148] By ensuring that there are two or more second through holes 2411, exhaust requirements can be met. At the same time, the size of each second through hole 2411 can be moderate, preventing the second through hole 2411 from being too large in diameter and affecting the strength of the fixing member 241, and preventing the second through hole 2411 from being too small in diameter and affecting ventilation efficiency. Furthermore, the area between two adjacent second through holes 2411 can be attached to the breathable membrane 242. When the gas inside the battery cell 20 acts on the breathable membrane 242 during discharge through the breathable membrane 242 to the outside of the battery cell 20, the fixing member 241 can provide a force opposite to the internal pressure of the battery cell 20 to the breathable membrane 242 in the area between the two adjacent second through holes 2411, thereby reducing the deformation of the breathable membrane 242, improving the overall internal pressure resistance of the breathable assembly 24, and thereby improving the reliability of the battery cell 20.

[0149] In some optional embodiments, the diameter N1 of the second through hole 2411 ranges from 0.5 mm to 3 mm.

[0150] The diameter N1 of the second through hole 2411 may be any value between 0.5 mm and 3 mm, including the two end values ​​of 0.5 mm and 3 mm, and may be 1 mm to 2 mm, such as 1.3 mm, 1.5 mm, 1.8 mm, etc.

[0151] By setting the diameter N1 of the second through hole 2411 to a value range of 0.5mm-3mm, the exhaust requirement of the second through hole 2411 can be guaranteed, which is conducive to setting the number of second through holes 2411 to more than two, and the strength of the fixing part 241 can also be guaranteed, thereby improving the ventilation efficiency of the second through hole 2411.

[0152] There can be multiple second through holes 2411. Along the radial direction of the first through hole 2321a, there are multiple minimum vertical distances between the outer edge of the breathable membrane 242 and the hole walls of the multiple second through holes 2411. The minimum value of the multiple minimum vertical distances N2 ranges from 1mm to 6mm.

[0153] Of course, in some optional embodiments, the number of the second through hole 2411 is one, and along the radial direction Y of the first through hole 2321a, the minimum vertical distance N2 between the outer edge of the breathable membrane 242 and the hole wall of the second through hole 2411 ranges from 1 mm to 6 mm.

[0154] When the number of the second through hole 2411 is one, the minimum vertical distance N2 between the outer edge of the breathable membrane 242 and the hole wall of the second through hole 2411 can be any value between 1mm and 6mm, including 1mm, 6mm, and can be optionally 2mm to 5mm. For example, 2mm, 3mm, 4mm, and 5mm can be used.

[0155] When there are multiple second through holes 2411, the plurality of second through holes 2411 may be located closer to the outer edge of the gas permeable membrane 242 or further away from the outer edge of the gas permeable membrane 242 in the radial direction Y relative to the first through hole 2321a. The minimum vertical distance N2 between the second through hole 2411 located outward in the radial direction Y and closest to the edge of the gas permeable membrane 242 and the gas permeable edge may be any value between 1 mm and 6 mm, including 1 mm and 6 mm, and may optionally be between 2 mm and 5 mm, and illustratively, may be 2 mm, 3 mm, 4 mm, or 5 mm.

[0156] With the above arrangement, regardless of whether one or more breathable membranes 242 are used, the distance between the hole wall of the second through hole 2411 and the edge of the breathable membrane 242 can be moderate, thereby ensuring the bonding strength between the breathable membrane 242 and the fixing member 241 while ensuring the ventilation effect.

[0157] In some optional embodiments, along the radial direction Y of the first through hole 2321 a , a first vertical distance between the outer edge of the breathable membrane 242 and the outer edge of the fixing member 241 is d, and the value range of d is 1 mm-5 mm.

[0158] The value range of d can be any value between 1mm-5mm, including the two end values ​​of 1mm and 5mm, and can be selected as any value between 1.5mm-4mm. For example, 2mm, 3mm, etc. can be used.

[0159] By setting the value range of d to 1mm-5mm, the value of d can be made moderate, which is beneficial for preventing the residual heat of laser welding from melting the breathable membrane 242 when the fixing member 241 is connected to the wall portion 231 by welding or other methods. At the same time, it can also avoid the value of d being too large, ensuring the number of breathable holes and thus ensuring the breathable effect.

[0160] In the battery cells provided by some embodiments of the present application, along the first direction X, the first accommodating section 2322 may be located on a side of the second accommodating section 2323 that is away from the electrode assembly 22 .

[0161] Of course, as shown in FIG. 9 , the first accommodating section 2322 may also be located on the side of the second accommodating section 2323 facing the electrode assembly 22 .

[0162] The shell 21 and the end cap assembly 23 together form the outer shell 201 of the battery cell 100. The shell 21 is a component that cooperates with the end cap assembly 23 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 22, electrolyte, and other components. The shell 21 and the end cap assembly 23 can be independent components. An opening can be provided in the shell 21, and the end cap assembly 23 is closed at the opening to form the internal environment of the battery cell 20. Alternatively, the end cap assembly 23 and the shell 21 can be integrated. Specifically, the end cap assembly 23 and the shell 21 can form a common connection surface before other components are inserted into the shell. When the interior of the shell 21 needs to be encapsulated, the end cap assembly 23 is closed to the shell 21. The shell 21 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 21 can be determined based on the specific shape and size of the electrode assembly 22. The shell 21 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0163] The battery cell 20 provided in the embodiment of the present application includes a shell 201, a breathable component 24 and a support member 25. The shell 201 includes a shell 21 and an end cover component 23. The shell 21 has an opening, and the end cover component 23 is set to close the opening. The wall portion 231 can be a cover plate 233 of the end cover component 23. The outer surface of the wall portion 231 is provided with a receiving groove 232 extending along the first direction X. The breathable component 24 is at least partially disposed in the receiving groove 232 and between the bottom wall 2321 of the receiving groove 232. The breathable component 24 is arranged to be separated, and the breathable component 24 includes a fixing part 241 and a breathable membrane 242. The fixing part 241 is connected to the wall part, and a plurality of second through holes 2411 extending along the first direction X are provided on the fixing part 241. The breathable membrane 242 includes a covering part 2421 and a connecting part 2422 arranged around the covering part 2421. The covering part 2421 is arranged to cover the second through holes 2411 in the first direction X, and is used to discharge the gas inside the battery cell 20. The connecting part 2422 is connected to the fixing part 241. The accommodating groove 232 includes a first accommodating section 2322 and a second accommodating section 2323 distributed along the first direction X. The first accommodating section 2322 is recessed from the outer surface of the wall portion 231. The radial Y dimension of the first accommodating section 2322 is greater than the maximum radial Y dimension of the second accommodating section 2323. The second accommodating section 2323 includes a first sub-accommodating section 2323a and a second sub-accommodating section 2323b distributed along the first direction X. The radial Y dimension of the first sub-accommodating section 2323a is greater than the radial Y dimension of the second sub-accommodating section 2323b and smaller than the radial Y dimension of the first accommodating section 2322. A first step surface 2324 is connected between the side wall surface of the first sub-accommodating section 2323a and the side wall surface of the first accommodating section 2322. At least a portion of the breathable membrane 242 is located within the first sub-accommodating section 2323a, and at least a portion of the support member 25 is located within the second sub-accommodating section 2323b. The support member 25 is generally annular and is disposed around the first through hole 2321a. It seals and engages with the connecting portion 2422 and the bottom wall 2321 of the receiving groove 232, respectively. The support member 25 includes an elastic sealing ring 251, which is compressed and clamped between the connecting portion 2422 and the bottom wall 2321 of the receiving groove 232 in the first direction X. A groove 2321b is formed on the bottom wall 2321 of the receiving groove 232 on one side facing the vent assembly 24. The elastic sealing portion of the support member 25 is partially accommodated in the groove 2321b.

[0164] According to some embodiments of the present application, the present application further provides a battery, comprising the battery cell 20 described in any of the above solutions.

[0165] According to some embodiments of the present application, the present application further provides an electrical device, comprising the battery described in any of the above schemes, and the battery is used to provide electrical energy to the electrical device.

[0166] The power-consuming device may be any of the aforementioned devices or systems using batteries.

[0167] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: Electrode assembly, A shell, used to accommodate the electrode assembly, the shell comprising a wall portion, an outer surface of the wall portion is provided with a receiving groove extending along a first direction, a bottom wall of the receiving groove is provided with a first through hole, and the first through hole is used to connect the space inside the shell with the receiving cavity of the receiving groove; a breathable component, at least partially disposed in the receiving groove and spaced apart from the bottom wall of the receiving groove, the breathable component comprising a fixing member and a breathable membrane, the fixing member being connected to the wall portion, the fixing member being provided with a second through hole extending along the first direction, the breathable membrane comprising a covering portion and a connecting portion disposed around the covering portion, the covering portion being provided to cover the second through hole in the first direction for discharging gas inside the battery cell, the connecting portion being connected to the fixing member; The support member has at least a portion clamped between the bottom wall of the accommodating groove and the connecting portion.

2. The battery cell according to claim 1, characterized in that: The support member is annular as a whole, is arranged around the first through hole, and is sealed and matched with the connecting portion and the bottom wall of the accommodating groove respectively.

3. The battery cell according to claim 1 or 2, characterized in that: A groove is formed on a surface of a bottom wall of the receiving groove facing the air permeable component, and a portion of the support member is received in the groove.

4. The battery cell according to any one of claims 1 to 3, characterized in that: The accommodating groove includes a first accommodating section and a second accommodating section distributed along the first direction, the first accommodating section is recessed from the outer surface of the wall portion, the radial dimension of the first accommodating section is greater than the maximum radial dimension of the second accommodating section, a first step surface is connected between the side wall surface of the first accommodating section and the side wall surface of the second accommodating section, the fixing member is at least partially located in the first accommodating section and supported on the first step surface, and at least part of the breathable membrane and / or at least part of the support member are arranged in the second accommodating section.

5. The battery cell according to claim 4, characterized in that: Along the first direction, the depth of the first accommodating section is H1, and the thickness of the fixing member is T, wherein 0.3≤H1 / T≤2.

5.

6. The battery cell according to claim 5, characterized in that: 1≤H1 / T≤2.

5.

7. The battery cell according to any one of claims 4 to 6, characterized in that: The second containing section includes a first sub-containing section and a second sub-containing section distributed along the first direction, the radial dimension of the first sub-containing section is larger than the radial dimension of the second sub-containing section and smaller than the radial dimension of the first containing section, the first step surface is connected between the side wall surface of the first sub-containing section and the side wall surface of the first containing section, at least part of the breathable membrane is located in the first sub-containing section, and at least part of the support member is located in the second sub-containing section.

8. The battery cell according to claim 7, characterized in that: Along the first direction, the depth of the first sub-containing section is H2, and the thickness of the breathable membrane is M, wherein 0≤H2-M≤0.7 mm.

9. The battery cell according to claim 7 or 8, characterized in that: Along the first direction, the depth of the second sub-accommodating section is H3, and the thickness of the supporting member is Q, wherein 0.1≤H3 / Q≤0.

95.

10. The battery cell according to any one of claims 7 to 9, characterized in that: Along the radial direction of the first through hole, there is a gap between the support member and the side wall of the second sub-accommodating section.

11. The battery cell according to claim 10, characterized in that: Along the radial direction of the first through hole, the outer diameter of the second sub-accommodating section is D1, and the outer diameter of the supporting member is D2, wherein 0.2≤D2 / D1≤0.

95.

12. The battery cell according to any one of claims 1 to 11, characterized in that: The support member includes an elastic sealing ring, which is compressed in the first direction and clamped between the connecting portion and the bottom wall of the accommodating groove.

13. The battery cell according to claim 12, characterized in that: The number of the elastic sealing rings is more than two, and the more than two elastic sealing rings are coaxially arranged and distributed along the radial direction of the first through hole.

14. The battery cell according to claim 12 or 13, characterized in that: Along the first direction, the orthographic projection of the elastic sealing ring is in the shape of a circular ring, an elliptical ring or a polygonal ring.

15. The battery cell according to any one of claims 1 to 14, characterized in that: The number of the second through holes is plural and they are distributed at intervals on the fixing member.

16. The battery cell according to claim 15, characterized in that: The diameter of the second through hole ranges from 0.5 mm to 3 mm.

17. The battery cell according to any one of claims 1 to 16, characterized in that: There is one second through hole, and along the radial direction of the first through hole, the minimum vertical distance between the outer edge of the breathable membrane and the hole wall of the second through hole is N, and the value range of N is 1mm-6mm; Or, there are multiple second through holes, and along the radial direction of the first through holes, there are multiple minimum vertical distances between the outer edge of the breathable membrane and the hole walls of the multiple second through holes, the minimum value of the multiple minimum vertical distances is N, and the value range of N is 1mm-6mm.

18. The battery cell according to any one of claims 1 to 17, characterized in that: Along the radial direction of the first through hole, a first vertical distance between the outer edge of the breathable membrane and the outer edge of the fixing member is d, and the value range of d is 1 mm-5 mm.

19. The battery cell according to any one of claims 1 to 18, characterized in that: The housing includes a shell and an end cover assembly, the shell has an opening, the end cover assembly is arranged to close the opening, and one of the shell and the end cover assembly includes the wall portion.

20. A battery, characterized in that: Comprising a battery cell as claimed in any one of claims 1 to 19.

21. An electrical device, characterized in that: Comprising a battery as claimed in claim 20, the battery is used to provide electrical energy.

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