Battery cell, battery device, and electric device
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-02
- Publication Date
- 2026-06-23
Smart Images
Figure CN224400584U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to a battery cell, a battery device, and an electrical device. Background Technology
[0002] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing.
[0003] In the development of battery technology, improving the reliability of individual battery cells is a key research direction. Utility Model Content
[0004] This application provides a battery cell, a battery device, and an electrical device that can improve the reliability of the battery cell.
[0005] In a first aspect, embodiments of this application provide a battery cell, which includes a housing, an electrode assembly, an end cap, and a pressure relief mechanism. The housing has a receiving cavity, and an opening is provided on one side of the receiving cavity along a first direction. The electrode assembly is disposed within the receiving cavity. The end cap is disposed over the opening of the housing and includes a cover body, a filter element, and an insulating element. The cover body has a pressure relief port, and the filter element and the insulating element are disposed on the side of the cover body facing the electrode assembly. The pressure relief mechanism is disposed at the pressure relief port, and the projection of the filter element along the first direction at least partially overlaps with the projection of the pressure relief mechanism along the first direction. The filter element includes a mesh portion and a support portion stacked along the first direction. The mesh portion is used to block at least some solid particles inside the battery cell from passing through, and the melting point of the support portion is greater than the melting point of the insulating element.
[0006] In the above solution, by providing an insulating component on the side of the cover facing the electrode assembly, the electrical connection components inside the housing can be isolated from the cover, reducing the risk of short circuits. This also effectively supports the end face of the electrode assembly, reducing the possibility of the electrode assembly moving along the first direction. By providing a filter component on the side of the cover facing the electrode assembly, the filter component includes a screen portion and a support portion stacked along the first direction. The projection of the filter component along the first direction at least partially overlaps with the projection of the pressure relief mechanism along the first direction. When a battery cell experiences thermal runaway, because the melting point of the support portion is set higher than that of the insulating component, even if the insulating component melts, the support portion can still provide mechanical support. The screen portion has a high-temperature gas-solid separation effect, allowing the gas generated by thermal runaway to pass smoothly when the pressure relief mechanism opens the valve, while blocking at least some solid particles inside the battery cell from passing through. This reduces the phenomenon of high-temperature hot solid particles igniting the thermal runaway gas caused by thermal runaway of the battery cell, improving the reliability of the battery cell.
[0007] In some embodiments, the filter element is disposed between the insulator and the cover, with at least a portion of the insulator covering the side of the filter element facing the electrode assembly.
[0008] In the above solution, by placing the filter between the insulating member and the cover, and by using at least a portion of the insulating member to cover the side facing the electrode assembly, the supporting and insulating effect of the insulating member on the electrode assembly can be improved, thereby further enhancing the reliability of the battery cell.
[0009] In some embodiments, the screen portion is located on the side of the support portion facing the electrode assembly.
[0010] In the above solution, by setting the screen part on the side of the support part facing the electrode assembly, the screen part is closer to the electrode assembly. When the battery cell experiences thermal runaway, the screen part can preferentially intercept solid particles, reducing the possibility of solid particles reaching the pressure relief mechanism or other areas of the cover.
[0011] In some embodiments, the screen portion is located on the side of the support portion away from the electrode assembly.
[0012] In the above solution, by setting the screen part on the side of the support part away from the electrode assembly, the support part is closer to the electrode assembly. When the battery cell experiences thermal runaway, the support part with a higher melting point can withstand the direct impact of high-temperature airflow, effectively protecting the screen part and preventing it from being damaged or blocked prematurely due to high temperature or particle impact to a certain extent.
[0013] In some embodiments, the support is a metal component.
[0014] In the above solution, by setting the support part as a metal part, the support strength of the support part can be guaranteed to a certain extent.
[0015] In some embodiments, the filter element further includes a first insulating layer, at least a portion of which is disposed on the side of the support facing the electrode assembly.
[0016] In the above solution, by providing a first insulating layer on the side of the support facing the electrode assembly, even if the insulating component melts when the battery cell experiences thermal runaway, the risk of a short circuit caused by direct contact between the support and the electrode assembly can be reduced, thereby further improving the reliability of the battery cell.
[0017] In some embodiments, the melting point of the first insulating layer is greater than the melting point of the insulating element.
[0018] In the above scheme, by setting the melting point of the first insulating layer to be greater than that of the insulating component, the first insulating layer is less likely to melt when the battery cell experiences thermal runaway, thereby improving the thermal stability of the first insulating layer.
[0019] In some embodiments, the melting point of the screen portion is greater than the melting point of the insulating element.
[0020] In the above scheme, by setting the melting point of the screen part to be greater than that of the insulating part, the stability of the screen part can be improved when the battery cell experiences thermal runaway.
[0021] In some embodiments, the screen part is made of metal.
[0022] In the above solution, by setting the screen part as a metal part, the stability of the screen part can be improved, making the screen part less prone to deformation or melting.
[0023] In some embodiments, the filter element further includes a second insulating layer that wraps around the surface of the screen portion.
[0024] In the above solution, by wrapping a second insulating layer on the surface of the screen, even if the insulating component melts when the battery cell experiences thermal runaway, the risk of a short circuit caused by direct contact between the screen and the electrode assembly can be reduced, thereby further improving the reliability of the battery cell.
[0025] In some embodiments, the melting point of the second insulating layer is greater than the melting point of the insulating element.
[0026] In the above scheme, by setting the melting point of the second insulating layer to be greater than that of the insulating component, the second insulating layer is less likely to melt when the battery cell experiences thermal runaway, thereby improving the thermal stability of the second insulating layer.
[0027] In some embodiments, the melting point of the support is greater than or equal to 300°C, which can ensure to a certain extent that the support is not prone to melting when the battery cell experiences thermal runaway.
[0028] In some embodiments, the screen part is provided with a plurality of screen holes, and the support part is provided with a plurality of connecting holes, which are respectively connected to the pressure relief port and the receiving cavity; the area of the screen holes is smaller than the area of the connecting holes.
[0029] In the above scheme, by setting the area of the mesh hole to be smaller than the area of the connecting hole, the high-temperature and high-pressure gas inside the battery cell can be discharged to the outside of the casing more smoothly through the connecting hole when thermal runaway occurs, and at least some high-temperature solid particles are intercepted by the mesh hole.
[0030] In some embodiments, the area of a single mesh hole is S1, and the area of a single connected hole is S2, wherein S1 and S2 satisfy: 0.001≤S1 / S2≤0.1.
[0031] In the above scheme, by limiting the area ratio of a single mesh hole to a single connecting hole to a suitable range, the probability of at least some high-temperature solid particles being intercepted when a battery cell experiences thermal runaway can be further increased.
[0032] In some embodiments, the projection of the mesh hole along the first direction and the projection of the connecting hole along the first direction at least partially overlap, which enables high-temperature and high-pressure gas to be discharged to the outside of the casing more smoothly through the connecting hole and the mesh hole when the battery cell experiences thermal runaway.
[0033] In some embodiments, the screen section is provided with a plurality of screen holes, and the area of a single screen hole is less than or equal to 0.25 mm. 2 .
[0034] In the above scheme, by setting the area of a single screen hole within a suitable range, it is possible to ensure to a certain extent that when a battery cell experiences thermal runaway, at least some high-temperature solid particles cannot be ejected from the screen hole to the outside of the casing.
[0035] In some embodiments, the projection of the pressure relief port along the first direction falls within the projection of the screen portion along the first direction, and the projection area of the pressure relief port along the first direction is smaller than the projection area of the screen portion along the first direction. This can ensure to a certain extent that when a battery cell experiences thermal runaway, at least some solid particles separate from the high-temperature gas and cannot be discharged from the pressure relief port.
[0036] Secondly, embodiments of this application also provide a battery device, including a battery cell of any of the above embodiments.
[0037] Thirdly, embodiments of this application also provide an electrical device, including the aforementioned battery device, which is used to provide electrical energy.
[0038] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description
[0039] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0040] Figure 1 This is a schematic diagram of the vehicle structure according to some embodiments of this application;
[0041] Figure 2 Exploded views of battery devices according to some embodiments of this application;
[0042] Figure 3 This is a schematic diagram of the structure of a battery module according to some embodiments of this application;
[0043] Figure 4 This is an exploded structural diagram of a battery cell according to some embodiments of this application;
[0044] Figure 5 This is a partially exploded structural diagram of a battery cell according to some embodiments of this application;
[0045] Figure 6 This is an exploded structural diagram of the support portion according to some embodiments of this application;
[0046] Figure 7 This is a cross-sectional schematic diagram of the support portion and the first insulating layer in some embodiments of this application;
[0047] Figure 8 This is a cross-sectional schematic diagram of the screen portion and the second insulating layer in some embodiments of this application;
[0048] Figure 9 This is an exploded structural diagram of the filter element in some embodiments of this application.
[0049] Explanation of reference numerals in the attached figures:
[0050] 1000, Vehicle; 100, Battery unit; 200, Controller; 300, Motor; 10, Top cover; 30, Housing; 400, Battery module; 20, Battery cell; 21, End cap; 22, Housing; 221, Receiving cavity; 222, Opening; 23, Electrode assembly; 24, Pressure relief mechanism; 40, Cover; 41, Pressure relief port; 50, Filter element; 51, Mesh screen; 511, Mesh screen hole; 52, Support part; 521, Connecting hole; 522, Bottom wall; 523, Side wall; 53, First insulating layer; 54, Second insulating layer; 60, Insulating element; X, First direction. Detailed Implementation
[0051] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.
[0052] In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the allowable tolerance range. "Parallel" is not parallel in the strict sense, but within the allowable tolerance range.
[0053] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.
[0054] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0055] In this application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., and the embodiments of this application are not limited thereto. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited thereto. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, cuboid / square battery cells, and pouch battery cells, and the embodiments of this application are not limited thereto.
[0056] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.
[0057] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells into a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.
[0058] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cell assemblies housed within the housing.
[0059] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be housed in the housing by fixing the battery module in the housing.
[0060] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.
[0061] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.
[0062] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.
[0063] Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside the vehicle 1000, and the battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.
[0064] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.
[0065] Please refer to Figure 2 , Figure 2 This is an exploded view of the apparatus provided in some embodiments of this application. The battery device 100 includes a battery housing and battery cells 20. In some embodiments, the battery housing may include a top cover 10 and a housing 30, with the top cover 10 and housing 30 covering each other, and the top cover 10 and housing 30 together defining a receiving cavity for receiving the battery cells 20. The housing 30 may be a hollow structure with one end open, and the top cover 10 may be a plate-like structure, with the top cover 10 covering the open side of the housing 30 so that the top cover 10 and housing 30 together define the receiving cavity; the top cover 10 and housing 30 may also be hollow structures with one side open, with the open side of the top cover 10 covering the open side of the housing 30. Of course, the battery housing formed by the top cover 10 and housing 30 can be of various shapes, such as a cylinder, a cuboid, etc.
[0066] Figure 3 This is a schematic diagram of the structure of a battery module according to some embodiments of this application. In the battery device 100, there can be multiple battery cells 20, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 20 are connected in both series and parallel. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed manner, and then the whole assembly of multiple battery cells 20 is housed in a housing. Of course, the battery device 100 can also be in the form of multiple battery cells 20 first connected in series, parallel, or in a mixed manner to form a battery module 400, and then multiple battery modules 400 are connected in series, parallel, or in a mixed manner to form a whole and housed in a housing. The battery device 100 may also include other structures. For example, the battery device 100 may also include a busbar component for realizing the electrical connection between multiple battery cells 20.
[0067] Each battery cell 20 can be a secondary battery cell or a primary battery cell; it can also be a lithium-sulfur battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, but is not limited to these. The battery cell 20 can be cylindrical, flat, cuboid, or other shapes.
[0068] When thermal runaway occurs inside the casing of a battery cell, a large amount of gas is generated, mainly composed of hydrogen, carbon monoxide, and alkanes, causing a rapid increase in internal pressure. This gas is typically released to the outside through a pressure relief mechanism on the end cap. However, the high internal temperature weakens the adhesion of the active material, allowing some of the runaway gas to escape with it. Furthermore, molten metal beads produced by thermal melting at high temperatures can also be carried out of the casing with the runaway gas. In the presence of sufficient oxygen from the outside air, the high-temperature solid particles ejected during thermal runaway may ignite a gas-solid reaction, reducing the reliability of the battery cell.
[0069] To address the aforementioned technical problems, this application provides a battery cell. By providing an insulating component on the side of the end cap facing the electrode assembly, the electrical connection components inside the housing can be isolated from the end cap, reducing the risk of short circuits. This also effectively supports the end face of the electrode assembly, reducing the possibility of the electrode assembly moving along a first direction. A filter component is provided on the side of the end cap facing the electrode assembly. This filter component includes a screen portion and a support portion stacked along the first direction. The projection of the filter component along the first direction at least partially overlaps with the projection of the pressure relief mechanism along the first direction. When the battery cell experiences thermal runaway, since the melting point of the support portion is set higher than that of the insulating component, even if the insulating component melts, the support portion can still provide mechanical support. The screen portion has a high-temperature gas-solid separation effect. When the pressure relief mechanism opens the valve, the gas generated by thermal runaway can pass smoothly, while the screen portion blocks at least some solid particles inside the battery cell from passing through. This reduces the phenomenon that high-temperature hot solid particles ejected due to thermal runaway of the battery cell ignite the thermal runaway gas, improving the reliability of the battery cell.
[0070] Please refer to Figure 4 , Figure 4This is an exploded structural diagram of a battery cell provided in some embodiments of this application. In a first aspect, embodiments of this application provide a battery cell 20, which includes a housing 22, an electrode assembly 23, an end cap 21, and a pressure relief mechanism 24. The housing 22 forms a receiving cavity 221, and an opening 222 is provided on one side of the receiving cavity 221 along a first direction X. The electrode assembly 23 is disposed within the receiving cavity 221. The end cap 21 covers the opening 222 of the housing 22, and the end cap 21 includes a cover body 40, a filter element 50, and an insulating element 60. The cover body 40 is provided with a pressure relief port. 41. The filter element 50 and the insulating element 60 are disposed on the side of the cover 40 facing the electrode assembly 23; the pressure relief mechanism 24 is disposed at the pressure relief port 41, and the projection of the filter element 50 along the first direction X at least partially overlaps with the projection of the pressure relief mechanism 24 along the first direction X; the filter element 50 includes a mesh portion 51 and a support portion 52 stacked along the first direction X, the mesh portion 51 is used to block at least part of the solid particles inside the battery cell 20 from passing through, and the melting point of the support portion 52 is greater than the melting point of the insulating element 60.
[0071] Battery cell 20 refers to the smallest unit that makes up a battery. End cap 21 refers to a component that covers the opening of housing 22 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 21 can be adapted to the shape of housing 22 to fit it. Optionally, the cap 40 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that end cap 21 is less prone to deformation under pressure and impact, giving battery cell 20 higher structural strength and improved safety performance. Electrode terminals can be used to electrically connect to electrode assembly 23 for outputting or inputting electrical energy into battery cell 20. Pressure relief mechanism is used to release internal pressure when the internal pressure or temperature of battery cell 20 reaches a threshold. The material of end cap 21 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment does not impose any special limitations on this.
[0072] The insulating component 60 is located between the cover 40 and the electrode assembly 23. The insulating component 60 can be a plastic part, either pre-molded as a single piece of plastic or assembled from various plastic components, and is made of insulating material. The insulating component 60 can also be made of other materials, such as rubber. The insulating component 60 has two main functions: first, it isolates the electrical connection components within the housing 22 from the cover 40 to reduce the risk of short circuits; second, it provides effective support to the end face of the electrode assembly 23. After the electrode assembly 23 is installed in the housing and the end cap 21 is welded, the internal core of the electrode assembly 23 is under slight pressure, which can easily affect the core's lifespan or cause a short circuit. Therefore, the insulating component 60 needs to effectively support the end face of the core to reduce the possibility of the electrode assembly 23 moving up and down.
[0073] The filter element 50 can be fixed to the cover 40 by welding, snap-fitting, or riveting; or the filter element 50 and the cover 40 can be integrally formed into a single structure. The screen portion 51 of the filter element 50 can be disposed between the support portion 52 and the cover 40, or it can be disposed on the side of the support portion 52 facing the electrode assembly 23. The screen portion 51 is provided with a plurality of screen holes 511 penetrating along the first direction X. The screen holes 511 can be rectangular, circular, elliptical, or other shapes. The area of a single screen hole 511 is small. For example, the screen holes 511 of the screen portion 51 can be greater than or equal to 6 mesh and less than or equal to 20 mesh, which can intercept at least part of the solid particles inside the casing 22 from escaping to the outside of the casing 22 when the battery cell 20 experiences thermal runaway.
[0074] The screen portion 51 can be disposed close to the support portion 52 along the first direction X, or it can be disposed at intervals. For example, a connecting hole 521 is provided in the support portion 52 along the first direction X. The area of a single connecting hole 521 can be larger than the area of a single screen hole 511. The screen portion 51 is disposed close to the support portion 52 along the first direction X. When the battery cell 20 experiences thermal runaway, high-temperature and high-pressure gas can be discharged through the connecting hole 521 of the support portion 52, the screen hole 511 of the screen portion 51, and the pressure relief port 41. At least some high-temperature solid particles are intercepted by the screen portion 51 and cannot be discharged outside the casing 22. Alternatively, the support portion 52 can be provided with a through-hole 521 in other directions. For example, if the first direction X is the up-down direction, then the through-hole 521 is provided on the side of the support portion 52. The through-hole 521 of the support portion 52 does not correspond to the screen hole 511 of the screen portion 51 in the first direction X. This can also allow the high-temperature and high-pressure gas to be discharged to the outside when the battery cell 20 experiences thermal runaway, while at least some high-temperature solid particles are intercepted.
[0075] The projection of the filter element 50 along the first direction X and the projection of the pressure relief mechanism 24 along the first direction X can partially overlap, or the projection of the filter element 50 along the first direction X can fall into the projection of the pressure relief mechanism 24 along the first direction X, so that when the battery cell 20 generates heat, the high temperature gas can be discharged more smoothly from the pressure relief port 41.
[0076] The filter element 50 can be disposed between the insulating element 60 and the pressure relief mechanism 24, with the insulating element 60 covering the filter element 50; or the surface of the filter element 50 can be provided with an insulating coating, or a through hole can be provided on the insulating element 60, through which the filter element 50 is exposed.
[0077] The melting point of the support part 52 is greater than that of the insulating part 60. For example, the support part 52 may include high-melting-point polymer materials such as polyimide, metal materials such as aluminum alloy, or ceramic materials, which have high melting points. Even if the insulating part 60 melts due to high temperature when the battery cell 20 undergoes thermal runaway, the support part 52 can still support the electrode assembly 23, which to a certain extent prevents the electrode assembly 23 from rising and blocking the pressure relief port 41, so that the high-temperature gas can be smoothly discharged to the outside of the housing 22 through the pressure relief port 41.
[0078] In the above solution, by providing an insulating member 60 on the side of the cover 40 facing the electrode assembly 23, the electrical connection components inside the housing 22 can be isolated from the cover 40, thereby reducing the risk of short circuits. This also effectively supports the end face of the electrode assembly 23, reducing the possibility of the electrode assembly 23 moving along the first direction X. By providing a filter member 50 on the side of the cover 40 facing the electrode assembly 23, the filter member 50 includes a mesh portion 51 and a support portion 52 stacked along the first direction X. The projection of the filter member 50 along the first direction X at least partially overlaps with the projection of the pressure relief mechanism 24 along the first direction X. When the battery cell 20 experiences thermal runaway, since the melting point of the support portion 52 is set to be greater than the melting point of the insulating member 60, even if the insulating member 60 melts, the support portion 52 can still provide mechanical support. The screen section 51 has the effect of high-temperature gas-solid separation. When the pressure relief mechanism 24 opens the valve, the gas generated by thermal runaway can pass through smoothly. The screen section 51 also blocks at least some solid particles inside the battery cell 20 from passing through, thereby reducing the phenomenon that the high-temperature hot solid particles ejected due to thermal runaway of the battery cell 20 will ignite the thermal runaway gas, and improving the reliability of the battery cell 20.
[0079] In some embodiments, the filter element 50 is disposed between the insulating element 60 and the cover 40, and at least a portion of the insulating element 60 covers the side of the filter element 50 facing the electrode assembly 23.
[0080] Vent holes may be provided on the insulating component 60, which are connected to the receiving cavity 221 inside the housing 22 and the pressure relief port 41 respectively. When the battery cell 20 experiences thermal runaway, the high-temperature and high-pressure gas inside the housing 22 can be discharged to the outside of the housing 22 through the vent holes of the insulating component 60, the connecting hole 521 of the support part 52, the screen hole 511 of the screen part 51, and finally through the pressure relief port 41.
[0081] The insulating component 60 may partially cover the filter component 50. For example, the vent of the insulating component 60 may correspond to the filter component 50, or the vent of the insulating component 60 may be located below the connecting hole 521 of the support portion 52 of the filter component 50. This allows the high-temperature and high-pressure gas inside the casing 22 to be discharged to the outside of the casing 22 at the shortest path and fastest speed when the battery cell 20 experiences thermal runaway. Alternatively, the vent of the insulating component 60 may not correspond to the connecting hole 521 of the support portion 52 of the filter component 50, and the insulating component 60 may completely cover the filter component 50.
[0082] In the above solution, by placing the filter element 50 between the insulating element 60 and the cover 40, and by using at least a portion of the insulating element 60 to cover the side of the electrode assembly 23, the supporting and insulating effect of the insulating element 60 on the electrode assembly 23 can be improved, thereby further enhancing the reliability of the battery cell 20.
[0083] Figure 5 This is a partially exploded structural diagram of a battery cell according to some embodiments of this application.
[0084] like Figure 5 As shown, in some embodiments, the screen portion 51 is located on the side of the support portion 52 facing the electrode assembly 23.
[0085] For example, the first direction X is the vertical direction, the screen part 51 is located on the upper side of the support part 52, the screen part 51 can be fixed to the support part 52, or the screen part 51 and the support part 52 can be unfixed.
[0086] Figure 6 This is an exploded structural diagram of the support portion according to some embodiments of this application.
[0087] like Figure 6 As shown, the support portion 52 may include a bottom wall 522 and a side wall 523. The bottom wall 522 is located on the side of the screen portion 51 facing the electrode assembly 23, and the side wall 523 is disposed on the outer periphery of the bottom wall 522. The bottom wall 522 is provided with a connecting hole 521 for gas to pass through. The side wall 523 may be arranged around the outer periphery of the bottom wall 522, or multiple spaced side walls 523 may be provided on the outer periphery of the bottom wall 522. The side wall 523 and the cover 40 may be connected by welding, snap-fitting, or riveting.
[0088] In the above solution, by setting the screen 51 on the side of the support 52 facing the electrode assembly 23, the screen 51 is closer to the electrode assembly 23. When the battery cell 20 experiences thermal runaway, the screen 51 can preferentially intercept solid particles, reducing the possibility of solid particles reaching the pressure relief mechanism 24 or other areas of the cover 40.
[0089] Figure 4 This is an exploded structural diagram of a battery cell according to some embodiments of this application.
[0090] like Figure 4 As shown, in some other embodiments, the screen portion 51 is located on the side of the support portion 52 opposite to the electrode assembly 23.
[0091] For example, the first direction X is the vertical direction, the screen part 51 is located on the lower side of the support part 52, and the screen part 51 can be fixed to the support part 52 by means of bonding, welding, snap-fitting, etc.
[0092] In the above scheme, by setting the screen part 51 on the side of the support part 52 away from the electrode assembly 23, the support part 52 is closer to the electrode assembly 23. When the battery cell 20 experiences thermal runaway, the support part 52 with a higher melting point can withstand the direct impact of the high-temperature airflow, effectively protecting the screen part 51 and preventing the screen part 51 from being damaged or blocked prematurely due to high temperature or particle impact to a certain extent.
[0093] In some embodiments, the support portion 52 is a metal component.
[0094] The support part 52 can be formed by materials such as aluminum and aluminum alloy. It has a large structural strength, not only does it have thermal stability, so it is not easy to melt when the battery cell 20 experiences thermal runaway, but it is also not easy to deform.
[0095] In the above solution, by setting the support part 52 as a metal part, the support strength of the support part 52 can be guaranteed to a certain extent.
[0096] Figure 7 This is a cross-sectional schematic diagram of the support portion and the first insulating layer in some embodiments of this application.
[0097] like Figure 7 As shown, in some embodiments, the filter element 50 further includes a first insulating layer 53, at least a portion of which is disposed on the side of the support 52 facing the electrode assembly 23.
[0098] The first insulating layer 53 can be formed in various ways. For example, an insulating coating can be formed on the surface of the support portion 52 by coating, spraying, or impregnation. The coating material can be a material with good insulation and heat resistance, such as ceramic, glass, or high-temperature resistant polymer (e.g., polyimide). Alternatively, the first insulating layer 53 can also be an independent insulating film, such as a mica sheet or a high-temperature resistant insulating film, fixed to the surface of the support portion 52 by bonding, hot pressing, or other methods.
[0099] At least a portion of the first insulating layer 53 is disposed on the side of the support portion 52 facing the electrode assembly 23. This can mean that the first insulating layer 53 completely covers the entire surface of the support portion 52 facing the electrode assembly 23, or that the first insulating layer 53 only covers a portion of the support portion 52, such as covering a critical area of the support portion 52 that may come into contact with the electrode assembly 23 or other live parts, or covering the solid portion of the support portion 52 other than the area where the connecting hole 521 is provided. When the support portion 52 has a connecting hole 521, the first insulating layer 53 can avoid the connecting hole 521 to a certain extent to prevent blockage of the gas passage, allowing for smooth gas discharge in the event of thermal runaway. The first insulating layer 53 can also cover the edge or wall of the connecting hole 521 to provide more comprehensive insulation protection. Furthermore, the first insulating layer 53 can extend further to the sidewall 523 or other surfaces of the support portion 52 to provide even more comprehensive insulation protection.
[0100] In the above solution, by providing a first insulating layer 53 on the side of the support portion 52 facing the electrode assembly 23, when the battery cell 20 experiences thermal runaway, even if the insulating component 60 melts, the risk of a short circuit caused by direct contact between the support portion 52 and the electrode assembly 23 can be reduced, thereby further improving the reliability of the battery cell 20.
[0101] In some embodiments, the melting point of the first insulating layer 53 is greater than the melting point of the insulating element 60.
[0102] When thermal runaway occurs in the battery cell 20, the insulating component 60 will reach its melting temperature and soften or melt before the first insulating layer 53. Since the insulating component 60 is typically made of conventional insulating materials such as plastics, its melting point is relatively low, making it prone to losing structural integrity and insulation performance under extreme high temperatures. In contrast, the first insulating layer 53 uses high-melting-point materials (such as ceramics, mica, polyimide, etc.), which can maintain its solid state and insulating properties at higher temperatures, thus preventing direct contact between the support portion 52 and the electrode assembly 23 or other charged components to a certain extent.
[0103] For example, when the battery cell 20 experiences thermal runaway, the temperature will exceed 150°C. If the insulating component 60 is made of common plastic materials such as polypropylene (PP, melting point about 160°C-170°C) or polyethylene (PE, melting point about 120°C-130°C), then the first insulating layer 53 can be made of materials with a melting point higher than 300°C, such as polyimide (PI, no obvious melting point, long-term use temperature can reach above 300°C), ceramic coating (melting point usually exceeds 1000°C), mica sheet (temperature resistance above 800°C), or glass fiber composite materials.
[0104] In the above scheme, by setting the melting point of the first insulating layer 53 to be greater than that of the insulating component 60, the first insulating layer 53 is less likely to melt when the battery cell 20 experiences thermal runaway, thereby improving the thermal stability of the first insulating layer 53.
[0105] In some embodiments, the melting point of the mesh section 51 is greater than the melting point of the insulating member 60.
[0106] When thermal runaway occurs in the battery cell 20, the insulating component 60 will reach its melting temperature and soften or melt before the screen portion 51. Since the insulating component 60 is typically made of conventional insulating materials such as plastics, its melting point is relatively low, making it prone to losing structural integrity and insulation performance at high temperatures. In contrast, the screen portion 51 is made of high-melting-point materials (such as metals, high-temperature resistant polymers, or ceramics), which can maintain its solid state and structural morphology at higher temperatures, ensuring, to a certain extent, the filtration effect of at least some high-temperature solid particles.
[0107] The melting point of the screen section 51 is higher than that of the insulating component 60. The specific value range can be set according to the design operating temperature of the battery cell 20 and the expected temperature of thermal runaway. For example, when the battery cell 20 experiences thermal runaway, the temperature will exceed 150°C. If the insulating component 60 is made of common plastic materials such as polypropylene (PP, melting point approximately 160°C-170°C) or polyethylene (PE, melting point approximately 120°C-130°C), then the screen section 51 can be made of materials with a melting point higher than 300°C. If the metal screen section 51 is made of aluminum (melting point approximately 660°C), copper (melting point approximately 1083°C), or stainless steel (melting point approximately 1400°C-1500°C), it has excellent high-temperature resistance. If high-temperature resistant polymers such as polyimide (with no obvious melting point, long-term operating temperature can reach above 300°C) or polyetheretherketone (PEEK, melting point approximately 343°C), or ceramic materials (melting point usually exceeds 1000°C) are used, the high melting point requirement can also be met.
[0108] In the above solution, by setting the melting point of the screen section 51 to be greater than that of the insulating member 60, the stability of the screen section 51 can be improved when the battery cell 20 experiences thermal runaway.
[0109] In some embodiments, the screen portion 51 is a metal part.
[0110] The screen section 51 can be made of metal parts such as stainless steel, aluminum, aluminum alloy, nickel, nickel alloy, copper, or copper alloy. Metal materials usually have high melting points. For example, the melting point of aluminum is about 660°C, and the melting point of stainless steel is about 1400°C-1500°C, which is much higher than the melting point of the plastic materials used in conventional insulating parts 60 (such as polypropylene, which has a melting point of about 160°C-170°C).
[0111] Furthermore, the metal component, serving as the screen part 51, possesses excellent mechanical strength and structural stability. During normal operation of the battery cell 20, the screen part 51 needs to withstand the vibrations, impacts, and pressures that may arise from the electrode assembly 23, as well as the pressure during assembly. In the event of thermal runaway, the screen part 51 also needs to withstand the impact of high-temperature, high-pressure airflow and the collision of solid particles. The metal material has high tensile strength, yield strength, and toughness, which can resist these mechanical and thermal stresses to a certain extent, reducing the risk of deformation, breakage, or detachment of the screen part 51.
[0112] In the above solution, by setting the screen part 51 as a metal part, the stability of the screen part 51 can be improved, making the screen part 51 less prone to deformation or melting.
[0113] Figure 8 This is a cross-sectional schematic diagram of the screen portion and the second insulating layer in some embodiments of this application.
[0114] like Figure 8 As shown, in some embodiments, the filter element 50 further includes a second insulating layer 54, which wraps around the surface of the screen portion 51.
[0115] The screen section 51 is made of a metallic material (such as stainless steel, aluminum, or aluminum alloy) to meet the requirements of high melting point and high strength. Metallic materials have good electrical conductivity. If the screen section 51 comes into direct contact with the electrode assembly 23 or other live parts during normal operation or thermal runaway of the battery cell 20, a short circuit may occur. The second insulating layer 54, by forming an electrical isolation layer on the surface of the screen section 51, reduces this short circuit risk.
[0116] The second insulating layer 54 can be formed on the surface of the screen section 51 by a coating process, such as spraying, dipping, brushing, or electrophoretic deposition, to uniformly cover the surface of the metal wire or screen plate of the screen section 51 with insulating material. The coating material can be ceramic material (such as alumina, zirconium oxide), glass glaze, high-temperature resistant polymer (such as polyimide, polyetheretherketone), or other materials with good insulation and heat resistance properties.
[0117] The second insulating layer 54 can also be attached to the surface of the screen section 51 by physical wrapping or bonding. For example, a pre-formed insulating film or insulating paper can be bonded to the surface of the screen section 51 and fixed by adhesive or hot pressing. For the screen section 51 with a woven metal wire mesh structure, a method of weaving insulating fibers and metal wires can be used, so that the insulating material directly becomes part of the screen structure, thereby achieving the wrapping of the insulating layer during the forming process.
[0118] The second insulating layer 54 can cover either partially or completely. Complete coverage means the second insulating layer 54 covers all exposed surfaces of the screen portion 51, including the wire surface, mesh edges, and the surrounding area of the screen portion 51, providing the most comprehensive insulation protection. Partial coverage, on the other hand, only covers critical areas of the screen portion 51 that may come into contact with the electrode assembly 23 or other live parts, such as the surface of the screen portion 51 facing the electrode assembly 23, or the edge portion of the screen portion 51.
[0119] In the above solution, by wrapping the surface of the screen portion 51 with a second insulating layer 54, when the battery cell 20 experiences thermal runaway, even if the insulating component 60 melts, the risk of a short circuit caused by direct contact between the screen portion 51 and the electrode assembly 23 can be reduced, thereby further improving the reliability of the battery cell 20.
[0120] In some embodiments, the melting point of the second insulating layer 54 is greater than the melting point of the insulating element 60.
[0121] Since the insulating component 60 is typically made of conventional insulating materials such as plastic, its melting point is relatively low, making it prone to losing structural integrity and insulation performance under extreme high temperatures. The second insulating layer 54, however, can be made of high-melting-point materials (such as ceramics, mica, polyimide, glass fiber composites, etc.), which can maintain solid-state and insulating properties at higher temperatures. When the battery cell 20 experiences thermal runaway, the insulating component 60 may melt first, but the second insulating layer 54 wrapped around the surface of the screen portion 51 can still maintain its insulating function, preventing direct contact between the conductive screen portion 51 and the electrode assembly 23 or other charged components, thus reducing the risk of short circuits caused by early failure of the insulating component 60.
[0122] The second insulating layer 54 can be made of materials with a melting point higher than 300°C, such as ceramic coatings (e.g., alumina, zirconium oxide, with melting points typically exceeding 2000°C) which have extremely high temperature resistance; mica sheets (with a temperature resistance of over 800°C) can also meet the high melting point requirements; high-temperature resistant polymers such as polyimide (PI, with no obvious melting point, and a long-term operating temperature of over 300°C) and polyether ether ketone (PEEK, with a melting point of approximately 343°C); and glass fiber composite materials (with a softening point typically above 500°C) also possess good heat resistance properties.
[0123] In the above scheme, by setting the melting point of the second insulating layer 54 to be greater than that of the insulating component 60, the second insulating layer 54 is less likely to melt when the battery cell 20 experiences thermal runaway, thereby improving the thermal stability of the second insulating layer 54.
[0124] In some embodiments, the melting point of the support portion 52 is greater than or equal to 300°C.
[0125] The material of the support part 52 can be aluminum alloy (such as 6061 aluminum alloy, melting point about 580℃-650℃), stainless steel (melting point about 1400℃-1500℃), pure copper or copper alloy (melting point about 1000℃-1083℃), titanium alloy (melting point about 1600℃-1700℃) and other metallic materials, or inorganic non-metallic materials such as alumina ceramic (melting point about 2050℃) and silicon nitride ceramic (melting point about 1900℃).
[0126] In the above scheme, by having the melting point of the support part 52 greater than or equal to 300°C, it is possible to ensure to a certain extent that the support part 52 is not prone to melting when the battery cell 20 experiences thermal runaway.
[0127] Figure 9 This is an exploded structural diagram of the filter element in some embodiments of this application.
[0128] like Figure 9 As shown, in some embodiments, the screen part 51 is provided with a plurality of screen holes 511, and the support part 52 is provided with a plurality of connecting holes 521, which are respectively connected to the pressure relief port 41 and the receiving cavity 221; the area of the screen hole 511 is smaller than the area of the connecting hole 521.
[0129] The mesh opening 511 can be circular, square, hexagonal, or other regular or irregular shapes. The area of the mesh opening 511 refers to the projected area of a single mesh opening 511 on a plane perpendicular to the first direction X. Similarly, the connecting hole 521 on the support 52 can be circular, rectangular, elongated, or other shapes. The area of the connecting hole 521 refers to the projected area of a single connecting hole 521 on a plane perpendicular to the first direction X.
[0130] The mesh screen holes 511 and the connecting holes 521 together form the gas flow path from the receiving cavity 221 to the pressure relief port 41. The main function of the mesh screen holes 511 is to intercept at least some solid particles while allowing gas to pass through. Therefore, the area of a single mesh screen hole 511 is smaller than the area of a single connecting hole 521 to block particles within a certain size range. The main function of the connecting holes 521 is to provide the main channel for gas flow and also serve as part of the support 52, providing mechanical support. Therefore, the connecting holes 521 can be designed to be larger to reduce gas flow resistance, allowing the large amount of gas generated during thermal runaway to be discharged quickly.
[0131] In the above scheme, by setting the area of the mesh hole 511 to be smaller than the area of the connecting hole 521, the high temperature and high pressure gas inside the battery cell 20 can be discharged from the outside of the casing 22 more smoothly through the connecting hole 521 when thermal runaway occurs, and at least some high temperature solid particles are intercepted by the mesh hole 511.
[0132] In some embodiments, the area of a single mesh hole 511 is S1, and the area of a single connecting hole 521 is S2, wherein S1 and S2 satisfy: 0.001≤S1 / S2≤0.1.
[0133] S1 / S2 can be any value between 0.001 and 0.1. For example, S1 / S2 can be 0.001, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09 or 0.1.
[0134] In the above scheme, by limiting the area ratio of a single mesh hole 511 to a single connecting hole 521 within a suitable range, the probability of high-temperature solid particles being intercepted when the battery cell 20 experiences thermal runaway can be further increased.
[0135] In some embodiments, the projection of the mesh hole 511 along the first direction X at least partially overlaps with the projection of the connecting hole 521 along the first direction X.
[0136] When viewed from the first direction X, the screen holes 511 on the screen section 51 and the connecting holes 521 on the support section 52 overlap in the projection plane. This projection overlap can be complete, meaning the entire projection of the screen holes 511 falls within the projection range of the connecting holes 521; or it can be partial, meaning a portion of the projection of the screen holes 511 overlaps with a portion of the projection of the connecting holes 521. Both complete and partial overlap provide a relatively direct path for gas flow.
[0137] In the above scheme, by setting the projection of the screen hole 511 along the first direction X to at least partially overlap with the projection of the connecting hole 521 along the first direction X, it is possible to make the high temperature and high pressure gas more smoothly discharged to the outside of the housing 22 through the connecting hole 521 and the screen hole 511 when the battery cell 20 experiences thermal runaway.
[0138] In some embodiments, the screen portion 51 is provided with a plurality of screen holes 511, and the area of a single screen hole 511 is less than or equal to 0.25 mm. 2 .
[0139] For example, the area of a single mesh opening 511 can be 0.01 mm. 2 0.05mm 2 0.1mm 2 0.15mm 2 0.18mm 2 0.2mm 2 0.22mm 2 0.25mm 2 wait.
[0140] The area of a single mesh opening 511 is less than or equal to 0.25 mm. 2 This means that the 511 mesh size can intercept particles larger than 0.25mm. 2 High-temperature solid particles of various sizes. When thermal runaway occurs in the battery cell 20, solid particles that may be generated inside include fragments of electrode active material, current collector metal debris, molten membrane residue, electrolyte decomposition products, etc. These particles have a wide size distribution, with the projected area of most particles exceeding 0.25 mm². By controlling the area of the mesh openings 511 below this value, these larger particles cannot pass directly through the mesh openings 511 and are thus intercepted on the side of the mesh section 51 facing the electrode assembly 23, reducing the possibility of them being ejected to the outside of the housing 22 by the airflow.
[0141] In the above scheme, by setting the area of a single mesh hole 511 within a suitable range, it can be ensured to a certain extent that when the battery cell 20 experiences thermal runaway, at least some high-temperature solid particles cannot be ejected from the mesh hole 511 to the outside of the casing 22.
[0142] In some embodiments, the projection of the pressure relief port 41 along the first direction X falls within the projection of the screen portion 51 along the first direction X, and the projection area of the pressure relief port 41 along the first direction X is smaller than the projection area of the screen portion 51 along the first direction X.
[0143] The projection of the pressure relief port 41 along the first direction X falls within the projection of the screen portion 51 along the first direction X. This means that when viewed from the first direction X, the entire outline of the pressure relief port 41 is within the boundary range of the screen portion 51. In other words, the screen portion 51 completely covers the area where the pressure relief port 41 is located in space. Any substance moving from the receiving cavity 221 toward the pressure relief port 41 must first pass through the area occupied by the screen portion 51. The projected area of the pressure relief port 41 along the first direction X is smaller than the projected area of the screen portion 51 along the first direction X, further confirming that the coverage area of the screen portion 51 is larger than the size of the opening 222 of the pressure relief port 41. The screen portion 51 is not only aligned with the pressure relief port 41 in position, but also has redundancy in size. Even if there is a certain deviation in assembly or slight displacement during thermal runaway, the screen portion 51 can still maintain effective coverage of the pressure relief port 41.
[0144] The above scheme can, to a certain extent, ensure that when the battery cell 20 experiences thermal runaway, at least some solid particles separate from the high-temperature gas and cannot be discharged from the pressure relief port 41.
[0145] Secondly, embodiments of this application also provide a battery device 100, including a battery cell 20 of any of the above embodiments.
[0146] Thirdly, embodiments of this application also provide an electrical device, including the aforementioned battery device 100, which is used to provide electrical energy.
[0147] According to some embodiments of this application, this application provides a battery cell, which includes a housing, an electrode assembly, an end cap, and a pressure relief mechanism. The housing has a receiving cavity with an opening on one side of the cavity along a first direction. The electrode assembly is disposed within the receiving cavity. The end cap covers the opening of the housing and includes a cover body, a filter element, and an insulating element. The cover body has a pressure relief port, and the filter element and the insulating element are disposed on the side of the cover body facing the electrode assembly. The pressure relief mechanism is disposed at the pressure relief port, and the projection of the filter element along the first direction at least partially overlaps with the projection of the pressure relief mechanism along the first direction. The filter element includes a mesh portion and a support portion stacked along the first direction, and the melting point of the support portion is greater than the melting point of the insulating element. The filter element is disposed between the insulating element and the cover body, and at least a portion of the insulating element covers the side of the filter element facing the electrode assembly.
[0148] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.
Claims
1. A battery cell, characterized in that, include: The housing has a receiving cavity, and an opening is provided on one side of the receiving cavity along a first direction; The electrode assembly is disposed within the receiving cavity; An end cap is provided over the opening of the housing. The end cap includes a cover body, a filter element, and an insulating element. The cover body is provided with a pressure relief port. The filter element and the insulating element are provided on the side of the cover body facing the electrode assembly. A pressure relief mechanism is provided at the pressure relief port, wherein the projection of the filter element along the first direction at least partially overlaps with the projection of the pressure relief mechanism along the first direction; The filter element includes a screen portion and a support portion stacked along the first direction. The screen portion is used to block at least some solid particles inside the battery cell from passing through, and the melting point of the support portion is greater than the melting point of the insulating element.
2. The battery cell according to claim 1, characterized in that, The filter element is disposed between the insulating element and the cover, and at least a portion of the insulating element covers the side of the filter element facing the electrode assembly.
3. The battery cell according to claim 1, characterized in that, The screen portion is located on the side of the support portion facing the electrode assembly.
4. The battery cell according to claim 1, characterized in that, The screen portion is located on the side of the support portion opposite to the electrode assembly.
5. The battery cell according to claim 1, characterized in that, The support part is a metal component.
6. The battery cell according to claim 5, characterized in that, The filter element further includes a first insulating layer, at least a portion of which is disposed on the side of the support facing the electrode assembly.
7. The battery cell according to claim 6, characterized in that, The melting point of the first insulating layer is greater than the melting point of the insulating component.
8. The battery cell according to claim 1, characterized in that, The melting point of the screen is greater than that of the insulating component.
9. The battery cell according to claim 1, characterized in that, The screen part is made of metal.
10. The battery cell according to claim 9, characterized in that, The filter element further includes a second insulating layer, which wraps around the surface of the screen portion.
11. The battery cell according to claim 10, characterized in that, The melting point of the second insulating layer is greater than the melting point of the insulating component.
12. The battery cell according to claim 1, characterized in that, The melting point of the support is greater than or equal to 300°C.
13. The battery cell according to claim 1, characterized in that, The screen part is provided with multiple screen holes, and the support part is provided with multiple connecting holes. The connecting holes are respectively connected to the pressure relief port and the receiving cavity; the area of the screen holes is smaller than the area of the connecting holes.
14. The battery cell according to claim 13, characterized in that, The area of a single mesh hole is S1, and the area of a single connecting hole is S2, wherein S1 and S2 satisfy: 0.001≤S1 / S2≤0.
1.
15. The battery cell according to claim 13, characterized in that, The projection of the mesh opening along the first direction at least partially overlaps with the projection of the connecting hole along the first direction.
16. The battery cell according to claim 1, characterized in that, The screen section is provided with multiple screen holes, and the area of a single screen hole is less than or equal to 0.25 mm. 2 .
17. The battery cell according to claim 1, characterized in that, The projection of the pressure relief port along the first direction falls within the projection of the screen portion along the first direction, and the projection area of the pressure relief port along the first direction is smaller than the projection area of the screen portion along the first direction.
18. A battery device, characterized in that, Includes the battery cell according to any one of claims 1-17.
19. An electrical appliance, characterized in that, Includes the battery device according to claim 18, the battery device being used to provide electrical energy.