Top cover assembly, battery monomer, battery and electric device

Abstract

The application belongs to the technical field of batteries, and discloses a top cover assembly, a battery monomer, a battery and an electric device. The top cover assembly comprises a top cover sheet and a pole. The top cover sheet has a first through hole penetrating in a second direction. The pole is arranged on the top cover sheet. The pole comprises at least one second connecting part and at least two first connecting parts arranged in a first direction. Each second connecting part is connected with two adjacent first connecting parts. The two adjacent first connecting parts are located on one side of the top cover sheet and are used for being connected with the same electric connecting piece. At least part of the second connecting part penetrates into the first through hole and is used for being connected with a tab. Each first connecting part is provided with a first welding area used for being connected with the electric connecting piece. The first welding areas of the two adjacent first connecting parts are arranged in the first direction. The battery provided by the application has a large connecting area between the electric connecting piece and the pole, and the connecting strength is high.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a top cover assembly, a battery cell, a battery, and an electrical device. Background Technology

[0002] In battery cell structural design, terminals are typically used to connect the tabs of the electrode assembly to external electrical connectors to allow current to flow in or out of the electrode assembly. Therefore, the current-carrying capacity of the terminals affects the charge / discharge capability and safety performance of the battery cell. In related technologies, battery cells consisting of a top cover assembly, electrode assembly, and casing often have limited width. This limited space restricts the design dimensions of the terminals, resulting in weaker current-carrying capacity and hindering improvements in the battery cell's charge / discharge performance and safety. Utility Model Content

[0003] The purpose of this application is to provide a top cover assembly, a battery cell, a battery, and an electrical device to solve the technical problem that the existing electrode post design is too wide and not suitable for battery cells with a smaller width.

[0004] Based on the above concept, the technical solution adopted in this application is:

[0005] Top cover assembly, including:

[0006] Top cover plate, having a first through hole extending in a second direction;

[0007] An electrode post is disposed on the top cover plate. The electrode post includes at least one second connecting portion and at least two first connecting portions arranged along a first direction, and each second connecting portion is connected to two adjacent first connecting portions. The two adjacent first connecting portions are located on one side of the top cover plate and are used to connect to the same electrical connector. At least a portion of the second connecting portion passes through the first through hole and is used to connect to the electrode tab. The first direction is the length direction of the top cover plate, and the second direction is the thickness direction of the top cover plate.

[0008] Each of the first connecting parts is provided with a first welding area, which is used to connect with the electrical connector. The first welding areas of two adjacent first connecting parts are spaced apart along the first direction.

[0009] In one or more embodiments of this application, the second connecting portion is provided with a second welding area, the second welding area being used to connect with the electrode tab, and along the second direction, there is a height difference between each of the first welding area and the second welding area.

[0010] In one or more embodiments of this application, along the first direction, a first wall is respectively connected to the opposite sides of the second connecting portion, and the end of each first wall away from the second connecting portion is connected to the corresponding first connecting portion.

[0011] In one or more embodiments of this application, along a third direction, a second wall is respectively connected to the opposite sides of the second connecting portion, and along the first direction, each second wall is connected between two adjacent first connecting portions; the third direction is the width direction of the top cover plate;

[0012] Along the circumference of the second connecting portion, each of the first walls is connected between two adjacent second walls, and the two first walls, the two second walls, and the second connecting portion together form a recess.

[0013] In one or more embodiments of this application, each of the second walls is further provided with a flange portion, the flange portion being connected to one end face of the second wall along the second direction and extending in the third direction away from the second connecting portion; along the third direction, the end face of the flange portion is flush with the end faces of the two adjacent first connecting portions.

[0014] In one or more embodiments of this application, the dimension of the first connecting portion in the third direction is W1, and the dimension of the flange portion in the third direction is W2, wherein:

[0015] 7mm≤W1≤32mm; and / or,

[0016] 1mm≤W2≤3mm; and / or,

[0017] 1%≤W2 / W1≤20%.

[0018] In one or more embodiments of this application, along the second direction, the second connecting portion includes a first metal layer and a second metal layer stacked together; the surface of the first metal layer facing away from the second metal layer is provided with a surface for welding the electrode tab;

[0019] The first metal layer extends into the first connecting portion at both ends in the first direction.

[0020] In one or more embodiments of this application, in the first direction, the distance between the end face of the first metal layer and the end face of the corresponding first connecting portion that is away from the second connecting portion is L1; the dimension of the first connecting portion in the first direction is L2;

[0021] 5mm≤L1≤25mm; and / or, 70%≤L1 / L2≤90%.

[0022] In one or more embodiments of this application, the first connecting portion has a groove on the side surface opposite to the top cover sheet. Along the first direction, the groove is located on the side of the first welding area facing the second connecting portion and extends along the third direction.

[0023] Along the second direction, the bottom wall of the groove is provided with a through second hole.

[0024] In one or more embodiments of this application, the top cover assembly further includes:

[0025] A first insulating component is fixedly connected to the pole post and the top cover plate. The first insulating component includes a first insulating part and a second insulating part connected together. The first insulating part is disposed between the first connecting part and the top cover plate, and the second insulating part covers the circumferential sidewall of the first connecting part. The first insulating component also includes a third insulating part, and a fourth insulating part and a fifth insulating part, both connected to the third insulating part. The third insulating part is disposed on the side of the top cover plate opposite to the first connecting part. The fourth insulating part passes through the top cover plate and is connected to the second insulating part. The fifth insulating part is disposed between the hole wall of the first through hole and the second connecting part.

[0026] The second insulating member is disposed on the side of the top cover plate away from the first connecting part. The second insulating member is provided with a third through hole corresponding to the first through hole. The third through hole penetrates the thickness direction of the second insulating member. The second connecting part passes through the first through hole and the third through hole in sequence.

[0027] A sealing ring is fitted onto the pole post, and the pole post, the first insulating part, the top cover plate and the fifth insulating part surround to form a receiving cavity, and the sealing ring is disposed in the receiving cavity.

[0028] In one or more embodiments of this application, a first insulating member includes a first insulating portion, a sixth insulating portion, and a seventh insulating portion connected together. The first insulating portion is disposed between the first connecting portion and the top cover plate. The sixth insulating portion is disposed between the hole wall of the first through hole and the second connecting portion. The seventh insulating portion is disposed on the side of the top cover plate opposite to the first connecting portion. On a dummy plane perpendicular to the second direction, the orthographic projection of the seventh insulating portion overlaps with the orthographic projection of the top cover plate.

[0029] The second insulating member is disposed on the side of the top cover plate away from the first connecting portion. The second insulating member has a third through hole corresponding to the first through hole. The third through hole penetrates the thickness direction of the second insulating member. The second connecting portion passes through the first through hole and the third through hole in sequence. The circumferential outer edge of the seventh insulating portion has a first inclined structure. The second insulating member has a second inclined structure that matches the first inclined structure. The second inclined structure abuts against the first inclined structure.

[0030] In one or more embodiments of this application, the first wall is a fused portion, and along a third direction, the size of the first wall is smaller than the size of the first connecting portion and the second connecting portion, wherein the third direction is the width direction of the top cover plate.

[0031] In one or more embodiments of this application, along the second direction, the surface of the second connecting portion near the first connecting portion is recessed, and the surface of the second connecting portion away from the first connecting portion is correspondingly protruded to form a protrusion. The protrusions are provided in the second welding area, and there are multiple protrusions.

[0032] In one or more embodiments of this application, a first insulating member is further included, the first insulating member being fixedly connected to the pole post and the top cover plate;

[0033] The surface of the electrode post in contact with the first insulating member is provided with a first nanopore, and the first insulating member is at least partially embedded in the first nanopore; and / or

[0034] The surface of the top cover sheet that contacts the first insulating member is provided with a second nanopore, and the first insulating member is at least partially embedded in the second nanopore.

[0035] In one or more embodiments of this application, the dimension of the first connecting part in the third direction is W1, the dimension of the top cover plate in the third direction is H2, the dimension of the first connecting part in the first direction is H3, the dimension of the top cover plate in the first direction is H4, and the dimension of the pole post in the first direction is H5;

[0036] 7mm≤W1≤32mm; and / or, 14mm≤H2≤40mm; and / or, 50%≤W1 / H2≤80%; and / or, 7mm≤H3≤28mm; and / or, 35mm≤H5≤80mm; and / or, 3%≤H3 / H4≤10%; and / or, 20%≤H3 / H5≤35%.

[0037] Battery cells, including:

[0038] The shell has an opening;

[0039] An electrode assembly having tabs is housed within the housing;

[0040] The aforementioned top cover assembly is installed over the opening of the housing.

[0041] The battery includes multiple electrical connectors and multiple battery cells as described above, with two adjacent battery cells connected by one of the electrical connectors.

[0042] The two adjacent first connection portions of the pole are welded to the same electrical connector, and along the first direction, the weld marks formed by the welding of the two first connection portions to the electrical connector are spaced apart.

[0043] In one or more embodiments of this application, along the second direction, the projection of the second connection portion and the projection of the electrical connector do not coincide or partially coincide.

[0044] A battery includes multiple electrical connectors and multiple battery cells, with adjacent battery cells connected by one of the electrical connectors; each battery cell includes: a housing having an opening; an electrode assembly having tabs, the electrode assembly being housed within the housing; and a top cover assembly covering the opening of the housing, the top cover assembly including:

[0045] Top cover plate, having a first through hole extending in a second direction;

[0046] An electrode post is disposed on the top cover plate. The electrode post includes at least one second connecting portion and at least two first connecting portions arranged along a first direction, and each second connecting portion is connected to two adjacent first connecting portions. The two adjacent first connecting portions are located on one side of the top cover plate and are used to connect to the same electrical connector. At least a portion of the second connecting portion passes through the first through hole and is used to connect to the electrode tab. The first direction is the length direction of the top cover plate, and the second direction is the thickness direction of the top cover plate.

[0047] Along the first direction, the welding of two adjacent first connecting portions to the electrical connector forms weld marks spaced apart.

[0048] The electrical device includes a battery cell as described above; or, the electrical device includes a battery as described above.

[0049] The beneficial effects of this application are:

[0050] The terminal post includes a second connecting portion for connecting the tab and a first connecting portion for connecting the electrical connector. The second connecting portion and the first connecting portion are arranged along the length direction of the top cover plate, so that the length direction of the terminal post is the same as the length direction of the top cover plate. When the width of the battery cell is small, the width of the top cover plate is small, but the length of the top cover plate is usually still large. This makes it easier to arrange a longer terminal post, reduces the influence of the width edge of the top cover plate on the size of the second connecting portion and the first connecting portion, and ensures the connection area between the terminal post and the electrical connector. Furthermore, there are at least two first connecting portions, and two adjacent first connecting portions in the first direction are connected to the same electrical connector, which can further increase the connection area between the terminal post and the electrical connector, thereby improving the current carrying capacity, connection strength and connection reliability of the terminal post and the electrical connector. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this application and these drawings without creative effort.

[0052] Figure 1 This is a schematic diagram of the structure of a battery provided in an embodiment of this application;

[0053] Figure 2 This is a schematic diagram of the structure of a single battery cell provided in an embodiment of this application;

[0054] Figure 3 This is an embodiment of the present application. Figure 2 A cross-sectional view of the battery cell shown;

[0055] Figure 4 This is an embodiment of the present application. Figure 3 The enlarged view at point A is shown below;

[0056] Figure 5 This is a schematic diagram of the structure of a cover plate assembly provided in an embodiment of this application;

[0057] Figure 6 This is an embodiment of the present application. Figure 5 An exploded view of the cover plate assembly shown;

[0058] Figure 7 This is a schematic diagram of the structure of a pole provided in an embodiment of this application;

[0059] Figure 8 This is a schematic diagram of another pole post structure provided in an embodiment of this application;

[0060] Figure 9This is an embodiment of the present application. Figure 8 Top view of the pole shown;

[0061] Figure 10 This is a schematic diagram of the structure of a first insulating element provided in an embodiment of this application;

[0062] Figure 11 This is a schematic diagram of another pole post structure provided in the embodiments of this application;

[0063] Figure 12 This is an embodiment of the present application. Figure 11 A schematic diagram of the pole piece from another perspective;

[0064] Figure 13 This is a schematic diagram of another battery structure provided in an embodiment of this application;

[0065] Figure 14 This is a schematic diagram of another battery cell provided in an embodiment of this application;

[0066] Figure 15 This is an embodiment of the present application. Figure 14 A top view of the battery cell shown;

[0067] Figure 16 This is an embodiment of the present application. Figure 15 The BB section view shown;

[0068] Figure 17 This is an embodiment of the present application. Figure 16 The enlarged view at point C is shown below;

[0069] Figure 18 This is an embodiment of the present application. Figure 14 Exploded view of the top cover assembly of the middle battery cell;

[0070] Figure 19 This is a schematic diagram of the structure of the first insulating member and the second insulating member provided in the embodiments of this application;

[0071] Figure 20 This is an embodiment of the present application. Figure 19 Side view of the structure shown;

[0072] Figure 21 This is a schematic diagram of the structure of another battery provided in the embodiments of this application;

[0073] Figure 22 This is an embodiment of the present application. Figure 21 The DD section view shown;

[0074] Figure 23 This is an embodiment of the present application. Figure 22 The enlarged view at point E is shown below;

[0075] Figure 24 This is an exploded view of another cover plate assembly provided in an embodiment of this application;

[0076] Figure 25 This is a schematic diagram of another pole post structure provided in the embodiments of this application;

[0077] Figure 26 This is a schematic diagram of a partial cross-sectional view of the battery provided in an embodiment of this application;

[0078] Figure 27 This is a schematic diagram of an electrical device provided in an embodiment of this application;

[0079] Figure 28 This is a schematic diagram of another electrical device provided in an embodiment of this application;

[0080] Figure 29 This is a schematic diagram of another electrical device provided in the embodiments of this application.

[0081] Explanation of reference numerals in the attached figures:

[0082] 1000, Battery; 100, Battery Cell; 10, Top Cover Assembly; 1, Top Cover Sheet; 11, First Through Hole; 12, Injection Hole; 13, First Shallow Groove; 2, Terminal Post; 21, Second Connecting Part; 211, Second Welding Area; 212, First Metal Layer; 213, Second Metal Layer; 214, Protrusion; 22, First Connecting Part; 221, First Welding Area; 222, Groove; 223, Second Through Hole; 23, First Wall; 24, Second Wall; 25, Recess; 26, Flanged Edge; 27, Second Shallow Groove; 3, First Insulation 31. First insulating part; 311. Bending part; 32. Second insulating part; 33. Sixth insulating part; 34. Seventh insulating part; 341. First inclined structure; 35. Eighth insulating part; 36. Third insulating part; 37. Fourth insulating part; 38. Fifth insulating part; 4. Second insulating element; 41. Third through hole; 45. Second inclined structure; 5. Sealing ring; 6. Pressure relief mechanism; 20. Housing; 30. Electrode assembly; 301. Electrode tab; 200. Electrical connector; X, First direction; Z, Second direction; Y, Third direction. Detailed Implementation

[0083] To make the technical problems solved by this application, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of this application will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining this application and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not all of them.

[0084] It should be understood that the phrase "an embodiment" or "one embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in one embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0085] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0086] In the description of this application, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0087] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. In the description of this embodiment, unless otherwise specified, "multiple" specifically refers to two or more.

[0088] In the description of this embodiment, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of description and simplification of operation. They 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 of this application. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0089] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on the other component or it can be located in between the component.

[0090] The technical solution of this application will be further described below with reference to the accompanying drawings and specific embodiments.

[0091] In related technologies, along the width direction of the top cover assembly, the pole is provided with a first connecting part located in the middle and two second connecting parts located on both sides of the first connecting part. The first connecting part is used for welding with the electrical connector, and the second connecting part is used for welding with the tabs of the electrode assembly. However, in related technologies, for battery cells with relatively small widths, the width design space of the top cover assembly is limited, which restricts the design size of the pole. Consequently, the welding area of ​​the first connecting part and the electrical connector is limited, resulting in weak current carrying capacity of the pole and the electrical connector, low connection strength and connection reliability, which is not conducive to improving the charging and discharging performance and safety performance of the battery cell.

[0092] Based on the above considerations, this application provides an electrical device, a battery, a battery cell, and a top cover assembly.

[0093] like Figures 27 to 29 As shown, the electrical devices disclosed in this application can be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, power tools, energy storage devices, amusement equipment, elevators and lifting equipment, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, or electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.; energy storage devices can be energy storage walls, base station energy storage, container energy storage, etc.; amusement equipment can be carousels, drop towers, etc.

[0094] like Figures 27 to 29As shown, an embodiment of this application describes an electrical device using a vehicle as an example. The vehicle 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 1000 is installed inside the vehicle, and the battery 1000 can be located at the bottom, front, or rear of the vehicle. The battery 1000 can be used to power the vehicle; for example, the battery 1000 can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor. The controller is used to control the battery 1000 to supply power to the motor, for example, for the vehicle's starting, navigation, and driving power needs. The battery 1000 can not only serve as the vehicle's operating power source but also as the vehicle's driving power source, replacing or partially replacing gasoline or natural gas to provide driving power to the vehicle.

[0095] As one embodiment of the battery 1000, the battery 1000 can be a battery pack or a battery module. When the battery 1000 is a battery pack, the battery pack specifically includes a battery management system (BMS) and multiple battery cells. The multiple battery cells can be electrically connected in series, parallel, or a combination of series and parallel connections, and communicate with the battery management system, which controls and monitors the operating status of each battery cell. Alternatively, the multiple battery cells can first be combined with a module management system to form a battery module, and then the multiple battery modules can be electrically connected in series, parallel, or a combination of series and parallel connections to form a battery pack together with the battery management system.

[0096] For example, such as Figure 1 As shown, multiple battery cells 100 can be installed on supporting structures such as housings, frames, and brackets. The individual battery cells 100 and the battery management system can be electrically connected through electrical connectors 200, which can be busbars.

[0097] The aforementioned battery cell 100 can be a secondary battery or a primary battery, and can also be a lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery. Its external outline can be cylindrical, flat, cuboid, or other shapes, but is not limited to these. Specifically, in this embodiment, the aforementioned battery cell 100 is a lithium-ion square battery.

[0098] As one embodiment of the battery cell 100, please refer to Figures 2 to 4A battery cell 100 refers to the smallest unit that makes up a battery. The battery cell 100 includes a housing 20, an electrode assembly 30, a top cover assembly 10, and other functional components. At least one end of the housing 20 has an opening, and the top cover assembly 10 covers the opening of the housing 20 to isolate the internal environment of the battery cell 100 from the external environment. The housing 20 has a cavity inside to accommodate the electrode assembly 30 within the cavity. The housing 20 is a component used to cooperate with the top cover assembly 10 to form the internal environment of the battery cell 100, wherein the formed internal environment can accommodate the electrode assembly 30, electrolyte, and other components. The housing 20 and the top cover assembly 10 can be independent components. An opening can be provided on the housing 20, and the top cover assembly 10 closes the opening to form the internal environment of the battery cell 100. The housing 20 can have various shapes and sizes, such as cylindrical, cuboid, hexagonal prism, etc. Specifically, the shape of the housing 20 can be determined according to the specific shape and size of the electrode assembly 30. The shell 20 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. This application embodiment does not impose any special restrictions on this.

[0099] As one embodiment of the electrode assembly 30, the electrode assembly 30 is a component in the battery cell 100 that undergoes an electrochemical reaction with the electrolyte. The housing 20 may contain one or more electrode assemblies 30. The electrode assembly 30 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. During the charging and discharging process of the battery cell 100, active ions (e.g., lithium ions) repeatedly insert and extract between the positive and negative electrode sheets. The separator, disposed between the positive and negative electrode sheets, can reduce short circuits between the positive and negative electrodes while allowing active ions to pass through. This application does not impose any particular limitation on the type of separator; any known porous separator with good chemical and mechanical stability can be selected. The positive electrode sheet may include a positive current collector and positive active material layers coated on opposite sides of the positive current collector. The negative electrode sheet may include a negative current collector and negative active material layers coated on opposite sides of the negative current collector. The portions of the positive and negative electrode plates containing active material constitute the main body of the electrode assembly 30, while the portions of the positive and negative electrode plates without active material each constitute a tab 301. That is, the electrode assembly 30 has tabs 301. The positive and negative tabs can be located together at one end of the main body or at opposite ends of the main body. The electrode assembly 30 is covered with an insulating film to reduce the risk of short circuits.

[0100] In some embodiments, each electrode assembly 30 extends a positive electrode tab and a negative electrode tab toward the end face of the top cover assembly 10, respectively. During the charging and discharging process of the battery 1000, the positive electrode active material and the negative electrode active material react with the electrolyte, and the electrode tab 301 connects to the terminal post 2 to form a current loop.

[0101] In some optional embodiments, the housing 20 includes two sets of electrode assemblies 30, each set of electrode assemblies 30 including one electrode assembly 30, and the two sets of electrode assemblies 30 are arranged side by side along the thickness direction of the housing 20. The two sets of positive electrode tabs of the two sets of electrode assemblies 30 are arranged opposite each other as positive electrodes, and the two sets of negative electrode tabs of the two sets of electrode assemblies 30 are arranged opposite each other as negative electrodes. The two sets of positive electrode tabs and the two sets of negative electrode tabs are spaced apart along the length direction of the housing 20. In other embodiments, the housing 20 may also include at least two sets of electrode assemblies 30, each set of electrode assemblies 30 may be one electrode assembly 30 or multiple electrode assemblies 30, which is not limited here. When each set of electrode assemblies 30 includes multiple electrode assemblies 30, the positive electrode tabs of each electrode assembly 30 are brought together to form one set of positive electrode tabs, and the negative electrode tabs are brought together to form one set of negative electrode tabs.

[0102] It should be noted that the length direction of the housing 20 is also the length direction of the top cover assembly 10 or the length direction of the electrode assembly 30, the thickness direction of the housing 20 is also the width direction of the top cover assembly 10 or the thickness direction of the electrode assembly 30, and the height direction of the housing 20 is also the height direction of the electrode assembly 30 or the thickness direction of the top cover sheet 1.

[0103] Before the electrode assembly 30 is installed into the housing 20, the electrode tabs 301 of the electrode assembly 30 are first assembled with the top cover assembly 10, for example, the electrode post 2 of the top cover assembly 10 is welded to the electrode tabs 301 of the electrode assembly 30, and then the electrode assembly 30 is installed into the housing 20.

[0104] As one embodiment of the top cover assembly 10, please refer to Figures 6 to 7 The top cover assembly 10 includes a top cover sheet 1, which covers the opening of the housing 20. The shape of the top cover sheet 1 can be adapted to the shape of the housing 20 to fit the opening. The top cover sheet 1 can be made of a material with a certain hardness and strength (such as aluminum alloy or aluminum), so that the top cover sheet 1 is less prone to deformation under pressure and impact, enabling the battery cell 100 to have higher structural strength and improved safety performance. The material of the top cover sheet 1 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this.

[0105] For example, such as Figure 6As shown, the top cover plate 1 has a first through hole 11 extending along the second direction Z. The first through hole 11 is used to install functional components, for example, the first through hole 11 is used to install the pole post 2.

[0106] In at least one possible implementation, such as Figure 5 and Figure 6 As shown, functional components such as pole posts 2, first insulating components 3, second insulating components 4, and pressure relief mechanisms 6 can be provided on the top cover plate 1. The top cover plate 1 and the functional components such as pole posts 2, first insulating components 3, second insulating components 4, and pressure relief mechanisms 6 provided on the top cover plate 1 together constitute the top cover assembly 10.

[0107] The terminal 2 can be electrically connected to the electrode assembly 30 for outputting or inputting electrical energy into the battery cell 100. The terminal 2 includes a positive terminal and a negative terminal. The positive terminal is connected to the positive electrode tab, thereby introducing the positive current of the battery cell into the interior of the housing 20 or leading it out to the exterior of the housing 20. The negative terminal is connected to the negative electrode tab, thereby introducing the negative current of the battery cell 100 into the interior of the housing 20 or leading it out to the exterior of the housing 20. The positive and negative terminals of adjacent battery cells 100 can be electrically connected in series, parallel, or in a mixed manner using electrical connectors.

[0108] It should be noted that the "terminal 2" mentioned in this application can be either a positive terminal or a negative terminal (unless otherwise specified). The "tab 301" mentioned in this application can be either a positive or a negative tab (unless otherwise specified), as long as the tab connected to the positive terminal is the positive tab and the tab connected to the negative terminal is the negative tab.

[0109] It should be noted that the first direction X, the second direction Z, and the third direction Y described in this application intersect each other. That is, the first direction X intersects the second direction Z, the first direction X intersects the third direction Y, and the second direction Z intersects the third direction Y. In some embodiments, the first direction X, the second direction Z, and the third direction Y are mutually perpendicular. The first direction X described in this application can be the length direction of the top cover plate 1, that is, the length direction of the electrode post 2, that is, the length direction of the electrode assembly 30 or the housing 20. The second direction Z can be the height direction of the electrode post 2, that is, the thickness direction of the top cover plate 1, that is, the height direction of the electrode assembly 30 or the housing 20. The third direction Y can be the width direction of the top cover plate 1, that is, the width direction of the electrode post 2, that is, the width direction of the electrode assembly 30 or the housing 20.

[0110] In at least one possible implementation, such as Figure 6 and Figure 7As shown, the electrode post 2 includes at least one second connecting portion 21 and at least two first connecting portions 22 arranged along a first direction X. The second connecting portions 21 are used to connect to the tabs 301 of the electrode assembly 30, and the first connecting portions 22 are used to connect to the electrical connector 200. Each second connecting portion 21 is connected to two adjacent first connecting portions 22, that is, the second connecting portions 21 and the first connecting portions 22 are arranged alternately. Two adjacent first connecting portions 22 are located on one side of the top cover plate 1, that is, two first connecting portions 22 connected to the same second connecting portion 21 are located on the same side of the top cover plate 1 and are used to connect to the same electrical connector 200, thereby increasing the connection area between the electrode post 2 and the electrical connector 200. In this embodiment, the first connecting portions 22 are provided on the side of the top cover plate 1 facing the outside of the housing 20 to facilitate connection with the electrical connector 200. At least a portion of the second connecting part 21 passes through the first through hole 11 to facilitate connection between the second connecting part 21 and the electrode tab 301. In this embodiment, at least two first connecting parts 22 can be arranged at intervals along the first direction X, that is, the two first connecting parts 22 are arranged at intervals along the length direction of the electrode post 2.

[0111] The second connecting part 21 of this application embodiment can be directly welded to the tab 301. Therefore, at least part of the second connecting part 21 passes through the first through hole 11 and extends into the housing 20 to be directly connected to the tab 301. No adapter structure is required, which reduces the use of parts, reduces the cost of the battery cell 100, and at the same time reduces the internal resistance of the battery cell 100 and increases the energy density of the battery cell 100.

[0112] In some other embodiments, the number of second connecting portions 21 is not limited to one, but can be two or more. The number of second connecting portions 21 is related to the number of first connecting portions 22. A second connecting portion 21 is provided between two adjacent first connecting portions 22. For example, when the number of first connecting portions 22 is 2, the number of second connecting portions 21 is 1. When the number of first connecting portions 22 is 3, the number of second connecting portions 21 is 2. When the number of first connecting portions 22 is 4, the number of second connecting portions 21 is 3, and so on. The first connecting portions 22 and the second connecting portions 21 are arranged alternately along the first direction X. For example, when the number of first connecting portions 22 is 3 and the number of second connecting portions 21 is 2, the pole post 2 along the first direction X includes a first connecting portion 22, a second connecting portion 21, a first connecting portion 22, a second connecting portion 21, and a first connecting portion 22 connected in sequence.

[0113] This embodiment of the application takes the example of two sets of electrode assemblies 30 arranged inside the housing 20, with each set of electrode assemblies 30 containing one electrode assembly 30. Since two electrode assemblies 30 can be arranged along the third direction Y inside the housing 20, the two electrode assemblies 30 can extend positive and negative electrode tabs from the same end. The two positive electrode tabs are arranged at intervals along the third direction Y, and the two negative electrode tabs are arranged at intervals along the third direction Y. The two sets of positive electrode tabs and the two sets of negative electrode tabs are arranged at intervals along the first direction X. Therefore, each electrode post 2 is provided with two first connecting parts 22 and one second connecting part 21. The two positive electrode tabs are connected to the same second connecting part 21, and the two negative electrode tabs are connected to the same second connecting part 21.

[0114] In this embodiment, as Figure 6 As shown, each first connecting portion 22 is provided with a first welding area 221. The first welding area 221 is used to connect with the electrical connector 200. The first welding areas 221 of two adjacent first connecting portions 22 are spaced apart along the first direction X and can be welded to the same electrical connector 200. It should be noted that the first welding area 221 can be part or all of the surface of the first connecting portion 22 that is away from the top cover plate 1. This embodiment does not limit this. The first welding areas 221 of two adjacent first connecting portions 22 being spaced apart along the first direction X can also be understood as: along the first direction X, the weld marks formed by welding two adjacent first connecting portions 22 to the electrical connector 200 are spaced apart.

[0115] The top cover assembly 10 provided in this embodiment includes a pole 2 comprising a second connecting portion 21 for connecting a tab 301 and a first connecting portion 22 for connecting an electrical connector 200. The second connecting portion 21 and the first connecting portion 22 are arranged along the length direction of the top cover sheet 1, such that the length direction of the pole 2 is the same as the length direction of the top cover sheet 1. When the width of the battery cell 100 is small, the width of the top cover sheet 1 is also small, but the length of the top cover sheet 1 is usually still large. This facilitates the arrangement of a longer pole 2, reduces the influence of the width edge of the top cover sheet 1 on the dimensions of the second connecting portion 21 and the first connecting portion 22, and ensures the connection area between the pole 2 and the electrical connector 200. Furthermore, at least two first connecting portions 22 are provided, and two adjacent first connecting portions 22 in the first direction X are connected to the same electrical connector 200, thereby further increasing the connection area between the pole 2 and the electrical connector 200, and thus improving the connection strength and reliability between the pole 2 and the electrical connector 200.

[0116] In some alternative implementations, such as Figure 6 or Figure 12As shown, the second connecting portion 21 is provided with a second welding area 211. The second welding area 211 is used to connect with the tab 301. In this embodiment, along the second direction Z, there is a height difference between each first welding area 221 and the second welding area 211. That is, the weld marks formed by the second connecting portion 21 connecting to the tab 301 and the weld marks formed by the first connecting portion 22 connecting to the electrical connector 200 are misaligned in the height direction. This arrangement facilitates the direct welding of the second connecting portion 21 to the tab 301 and also facilitates the direct welding of the first connecting portion 22 to the electrical connector 200. This ensures that the first connecting portion 22 will not interfere or obstruct the welding of the tab 301, and the second connecting portion 21 will not interfere or obstruct the welding of the electrical connector 200. This reduces the difficulty of welding operations, ensures welding quality, and thus ensures the safety of the battery cell 100.

[0117] In some embodiments, please continue to see Figure 7 Along the first direction X, a first wall 23 is connected to each of the opposite sides of the second connecting part 21. The two first walls 23 correspond one-to-one with the two connected first connecting parts 22. The end of each first wall 23 away from the second connecting part 21 is connected to the corresponding first connecting part 22 to realize the connection between the second connecting part 21 and the first connecting part 22.

[0118] In some alternative embodiments, such as Figure 7 As shown, the width of the first wall 23 can be relatively large. For example, the width of the first wall 23 is slightly smaller than the width of the second connecting part 21 or the first connecting part 22. In this way, the connection strength between the second connecting part 21 and the first connecting part 22 can be guaranteed, and the overcurrent resistance can be effectively reduced.

[0119] In other alternative embodiments, such as Figure 8 and Figure 9 As shown, the first wall 23 can be relatively narrow, that is, the width of the first wall 23 can be significantly smaller than the width of the second connecting portion 21 or the first connecting portion 22. In this embodiment, along the third direction Y, the size of the first wall 23 is smaller than the size of the first connecting portion 22 and the second connecting portion 21. In this case, the first wall 23 is a fuse. The fuse is used to melt when the temperature of the electrode post 2 is higher than a preset value, so as to cut off the electrical connection between the battery cell 100 where the electrode post 2 is located and the electrical connector 200, thereby reducing the impact on the entire battery and improving the safety of the battery. Thus, when an abnormality occurs in the circuit during actual use, because the overcurrent area of ​​the fuse is small, the temperature rise at the fuse is faster, and the fuse can melt quickly, thereby cutting off the circuit in time and greatly improving the safety of the battery.

[0120] In at least one embodiment, the top cover assembly 10 includes a first insulating member 3, which is fixedly connected to the pole post 2 and the top cover plate 1. That is, the pole post 2 and the top cover plate 1 are fixedly connected by the first insulating member 3. With this configuration, the first insulating member 3 can be used for both the connection between the pole post 2 and the top cover plate 1 and for insulation and sealing between them, making the first insulating member 3 more functional and simplifying the structure of the top cover assembly 10.

[0121] In some embodiments, a second nanopore (not shown) is provided on the surface of the top cover plate 1 and the first insulating member 3 that are in contact, and the first insulating member 3 is at least partially embedded in the second nanopore. This increases the bonding strength and sealing performance between the first insulating member 3 and the top cover plate 1. During manufacturing, the nanopore structure can be formed on the top cover plate 1 by chemical etching, thereby increasing the contact surface area between the first insulating member 3 and the top cover plate 1 and improving the bonding strength and sealing performance. By providing the second nanopore, the first insulating member 3 can be injection molded using a nano-injection molding process, facilitating the processing and manufacturing of the first insulating member 3. When the first insulating member 3 has a portion located on the side of the top cover plate 1 facing the tab 301, the second nanopore can also simultaneously form the outer and inner portions of the first insulating member 3 on the top cover plate 1, saving processing steps.

[0122] In at least one possible embodiment, the surfaces of the electrode post 2 and the first insulating member 3 that come into contact may be provided with first nanopores (not shown in the figure), and the first insulating member 3 is at least partially embedded in the first nanopores. This increases the bonding strength and sealing performance between the first insulating member 3 and the top electrode post 2. During manufacturing, the nanopore structure can be formed on the electrode post 2 by chemical etching, thereby increasing the contact surface area between the first insulating member 3 and the electrode post 2 and improving the bonding strength and sealing performance. By providing the first nanopores, the first insulating member 3 can be injection molded using a nano-injection molding process. When the first insulating member 3 has a portion located on the side of the top cover plate 1 facing the tab 301, the first nanopores can simultaneously form both the outer and inner portions of the first insulating member 3 on the top cover plate 1, saving processing steps.

[0123] Exemplarily, this embodiment provides a first insulating member 3, such as Figure 6 and Figure 10 As shown, the first insulating member 3 includes a first insulating portion 31, a sixth insulating portion 33, and a seventh insulating portion 34 connected together. Wherein, as... Figure 4As shown, both the first insulating part 31 and the seventh insulating part 34 are connected to the sixth insulating part 33. The first insulating part 31 is disposed between the first connecting part 22 and the top cover plate 1, and is used for insulation between the first connecting part 22 and the top cover plate 1. In this embodiment, the first insulating part 31 and the first connecting part 22 can be provided in a one-to-one correspondence, with each first insulating part 31 disposed between the corresponding first connecting part 22 and the top cover plate 1. The sixth insulating part 33 is disposed between the hole wall of the first through hole 11 and the second connecting part 21, and is used for insulation between the second connecting part 21 and the top cover plate 1. The seventh insulating part 34 is disposed on the side of the top cover plate 1 facing away from the first connecting part 22, and on a virtual plane perpendicular to the second direction Z, the orthographic projection of the seventh insulating part 34 overlaps with the orthographic projection of the top cover plate 1, that is, the orthographic projection of the seventh insulating part 34 along the second direction Z on the virtual plane at least partially coincides with the orthographic projection of the top cover plate 1 along the second direction Z on the virtual plane. The seventh insulating part 34 is provided to cooperate with the second insulating member 4, thereby further improving the sealing effect between the top cover plate 1 and the pole post 2. On the other hand, the seventh insulating part 34 can be bent toward the top cover plate 1 to form a hook structure. For example, the seventh insulating part 34 can abut against the surface of the top cover plate 1 facing the inside of the housing 20, so that the top cover plate 1 can limit the first insulating member 3 in the first direction X, reducing the risk that the first insulating member 3 will move away from the inside of the housing 20 and separate from the top cover plate 1, thereby ensuring the sealing function.

[0124] In this embodiment, the sixth insulating part 33 is annular and is disposed on the outer periphery of the second connecting part 21. The seventh insulating part 34 is connected to the end of the second connecting part 21 away from the sixth insulating part 33 and is annular.

[0125] It is understandable that when the pole post 2 includes the first wall 23, the first insulating member 3 also has a portion disposed between the first wall 23 and the top cover plate 1, for example, as Figure 10 As shown, the first insulating member 3 also includes an eighth insulating portion 35. (As indicated...) Figure 4 As shown, each sixth insulating part 33 is connected to the first insulating part 31 by an eighth insulating part 35, which covers the first wall 23 to achieve insulation between the first wall 23 and the top cover plate 1.

[0126] In at least one possible implementation, please refer to Figure 4 The edge of the first insulating portion 31 can be bent toward the first connecting portion 22 to form a bent portion 311. The bent portion 311 is used to abut against the circumferential side of the first connecting portion 22, thereby reducing the risk of short circuit between the circumferential side of the first connecting portion 22 and the top cover plate 1, and further improving the safety of the battery cell 100. Exemplarily, the bent portion 311 is annular. In this embodiment, the first connecting portion 22 has a portion protruding from the bent portion 311 to facilitate better contact with the electrical connector 200.

[0127] It is understandable that the first insulating part 31 may also be a flat plate structure disposed between the bottom of the first connecting part 22 and the top cover plate 1, but this embodiment does not limit it to this.

[0128] Optionally, the sixth insulating part 33 may or may not cover the outer surface of the second connecting part 21. When the outer surface of the second connecting part 21 is not covered, the second connecting part 21 may be combined with other heat dissipation structures to better dissipate heat from the pole post 2.

[0129] In at least one possible implementation, the top cover assembly 10 further includes a second insulating member 4 for insulation between the electrode tab 301 and the top cover sheet 1, and between the electrode assembly 30 and the top cover sheet 1. Exemplarily, such as... Figure 4 As shown, the second insulating member 4 is located on the side of the top cover plate 1 facing away from the first connecting portion 22, that is, the second insulating member 4 is located on the side of the top cover plate 1 facing the electrode assembly 30. The second insulating member 4 has a third through hole 41 corresponding to the first through hole 11, and the first through hole 11 and the third through hole 41 are connected. The third through hole 41 penetrates the thickness direction of the second insulating member 4, that is, the third through hole 41 is disposed along the thickness direction of the second insulating member 4. The thickness direction of the second insulating member 4 is the same as the second direction Z. The second connecting portion 21 passes through the first through hole 11 and the third through hole 41 in sequence and connects to the electrode tab 301. The portion of the second insulating member 4 without the third through hole 41 can cover the surface of the top cover plate 1 facing the electrode assembly 30, thereby achieving insulation.

[0130] In at least one possible implementation, such as Figure 10 As shown, the outer circumferential edge of the seventh insulating portion 34 has a first inclined structure 341, as... Figure 6 As shown, the second insulating member 4 has a second inclined structure 45 that matches the first inclined structure 341, such as Figure 4 As shown, the second inclined structure 45 abuts against the first inclined structure 341. By setting the first inclined structure 341 and the second inclined structure 45 to cooperate with each other, the first insulating member 3 and the second insulating member 4 can abut better. The surface of the first inclined structure 341 facing the second inclined structure 45 is inclined, and the surface of the second inclined structure 45 facing the first inclined structure 341 is inclined. This allows the first inclined structure 341 and the second inclined structure 45 to have a larger abutment area, thereby effectively improving the sealing and insulation effect. Furthermore, when subjected to compression, the first inclined structure 341 and the second inclined structure 45 can fit together more tightly, thereby reducing the risk of insulation failure and further improving the reliability and safety of the battery cell 100.

[0131] By providing a first insulating component 3 and a second insulating component 4, the processing and assembly difficulty of the insulating components can be reduced while ensuring the insulation and sealing effect. For example, the first insulating component 3 and the second insulating component 4 can be made of plastic materials, such as PP, PE, PPS, etc.

[0132] In some optional embodiments, the second connecting portion 21 and the electrode tab 301 can be connected by welding. The welding method can be laser welding or pressure welding. When pressure welding is used between the second connecting portion 21 and the electrode tab 301, in some possible embodiments, such as... Figure 11 and Figure 12 As shown, along the second direction Z, the surface of the second connecting portion 21 near the first connecting portion 22 is recessed, and the surface of the second connecting portion 21 away from the first connecting portion 22 is correspondingly raised to form a protrusion 214. Multiple protrusions 214 are provided in the second welding area 211. By providing the protrusions 214, during the pressure welding process, the protrusions 214 can melt and better connect with the tab 301, thereby improving the connection strength between the second connecting portion 21 and the tab 301. By providing multiple protrusions 214, the uniformity of welding with the tab 301 can be improved, reducing the risk of weak connection areas and further ensuring connection strength. It should be noted that the surface of the second connecting portion 21 near the first connecting portion 22 can also be understood as the surface of the second connecting portion 21 facing the electrical connector 200. The surface of the second connecting portion 21 away from the first connecting portion 22 can also be understood as the surface of the second connecting portion 21 facing the tab 301.

[0133] In at least one possible implementation, the pole post 2 can be formed by bending a sheet metal, that is, the pole post 2 in this embodiment can be a one-piece structure. In this embodiment, the protrusion 214 can be formed by stamping on the second connecting portion 21 to reduce manufacturing difficulty and improve production efficiency.

[0134] In at least one possible implementation, this embodiment also provides a pole post 2, which differs from the pole post 2 described above in that: the pole post 2 includes not only a first wall 23, but also a second wall 24.

[0135] For example, such as Figures 13 to 19 As shown, along the third direction Y, a second wall 24 is connected to each of the opposite sides of the second connecting portion 21. Each second connecting portion 21 corresponds to two second walls 24, which are connected to the two sides of the second connecting portion 21 along the third direction Y. The second walls 24 can extend along the second direction Z. Along the first direction X, each second wall 24 is connected between two adjacent first connecting portions 22, that is, two adjacent first connecting portions 22 are connected as one unit through the second wall 24.

[0136] Please see Figure 14Along the circumference of the second connecting portion 21, each first wall 23 connects between two adjacent second walls 24, such that the two first walls 23, the two second walls 24, and the corresponding second connecting portion 21 together form a recess 25. It can be seen that... Figures 13 to 19 The second connecting part 21 of the pole post 2 shown is sealed on both sides in the third direction Y.

[0137] In at least one possible implementation, the pole post 2, which includes the first wall 23 and the second wall 24, can be formed by deep drawing of sheet metal to facilitate the processing and manufacturing of the pole post 2.

[0138] In some embodiments, such as Figure 14 and Figure 15 As shown, each second wall 24 is also provided with a flange 26, that is, each second wall 24 is connected to a flange 26. The flange 26 is connected to one end face of the corresponding second wall 24 along the second direction Z. Specifically, one end of the second wall 24 in the second direction Z is connected to the second connecting part 21, and the other end of the second wall 24 in the second direction Z is connected to the flange 26. Figure 15 As shown, each flange 26 extends in the third direction Y away from the second connecting part 21, so that the flange 26 does not interfere with the welding of the second connecting part 21 and the tab 301.

[0139] The electrode post 2 provided in this embodiment features a flanged portion 26 connected to a second wall 24, which in turn connects to a second connecting portion 21, allowing the second connecting portion 21 to connect with the flanged portion 26. The flanged portion 26 can be coplanar with the first connecting portion 22 in the second direction Z, enabling the electrode post 2 to be formed entirely by a deep drawing process, thus reducing the difficulty of the deep drawing process. Furthermore, the flanged portion 26 can also contact the electrical connector 200, further increasing the contact area between the electrode post 2 and the electrical connector 200, thereby improving connection reliability.

[0140] In at least one possible implementation, such as Figure 15 As shown, along the third direction Y, the end face of the flange 26 is flush with the end faces of the two adjacent first connecting parts 22, making the overall structure of the electrode post 2 more regular, which facilitates processing and setting of insulating parts. Furthermore, the flange 26 does not additionally increase the width of the electrode post 2, allowing it to be used in batteries with high width requirements. Additionally, the flange 26 can connect two connected first connecting parts 22, reducing the risk of deformation of the first connecting parts 22 along the third direction Y. It should be noted that the second connecting part 21 is connected to first walls 23 at both ends along the third direction Y, and each first wall 23 is connected to a flange 26. The end face of the flange 26 along the third direction Y is flush with the corresponding end faces of the two connected first connecting parts 22.

[0141] In some embodiments, please continue to see Figure 15 The dimension of the first connecting portion 22 in the third direction Y is W1, and the dimension of the flange portion 26 in the third direction Y is W2. The value of W1 satisfies the condition: 7mm ≤ W1 ≤ 32mm. For example, W1 can be located within multiple intervals such as 7mm ≤ W1 ≤ 32mm, 7mm ≤ W1 ≤ 28mm, 10mm ≤ W1 ≤ 32mm, 10mm ≤ W1 ≤ 20mm, etc. Specifically, W1 = 7mm, 8mm, 10mm, 15mm, 20mm, 25mm, 28mm, 30mm, or 32mm, or any value between the two. This configuration ensures that the width of the first connecting portion 22 provides a sufficient welding area with the electrical connector 200, while also being suitable for battery cells 100 with smaller widths.

[0142] For example, W2 satisfies: 1mm ≤ W2 ≤ 3mm. For instance, W2 can be located within multiple intervals such as 1mm ≤ W2 ≤ 2mm, 1mm ≤ W2 ≤ 1.5mm, 2mm ≤ W2 ≤ 3mm, etc. Specifically, W2 = 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 1.2mm, 2.5mm, 2.8mm, or 3mm, or any value between the two. Through the above configuration, the flange 26 can have a certain width to facilitate connection with the electrical connector 200, and also to facilitate the support of the pole post 2 on the top cover plate 1 via the flange 26, thereby improving the positional stability of the pole post 2.

[0143] In some embodiments, the relationship between W1 and W2 satisfies: 1% ≤ W2 / W1 ≤ 20%. For example, W2 / W1 can be located within multiple intervals such as 1% ≤ W2 / W1 ≤ 10%, 10% ≤ W2 / W1 ≤ 20%, etc. Specifically, W2 / W1 = 1%, 3%, 5%, 8%, 10%, 13%, 15%, 18%, 19%, or 20%, or any value between any two of the above. Through the above settings, the width of the flange 26 is neither too large nor too small, thus ensuring that the second connecting portion 21 has sufficient connection area while preventing the pole post 2 from becoming too wide. Furthermore, the flange 26 also reduces the risk of deformation of the adjacent first connecting portion 22. When W2 / W1 is greater than 20%, the width of the flange 26 is large, which will cause the width of the second connecting portion 21 to decrease, affecting the connection strength between the second connecting portion 21 and the tab 301.

[0144] In this embodiment, the pole post 2 can be a one-piece structure or a composite structure; this embodiment does not limit this.

[0145] In at least one possible implementation, such as Figure 16 Only Figure 18As shown, along the second direction Z, the second connecting portion 21 includes a first metal layer 212 and a second metal layer 213 stacked together; that is, the electrode post 2 has a composite structure. It should be noted that when the second connecting portion 21 includes the first metal layer 212 and the second metal layer 213, the electrode post 2 can be a negative electrode post. However, the second connecting portion 21 of the positive electrode post can be formed with only one type of metal.

[0146] In this embodiment, the surface of the first metal layer 212 facing away from the second metal layer 213 is the surface used for welding the tab 301. That is, the second welding area 211 is disposed on the first metal layer 212. The first metal layer 212 and the second metal layer 213 are made of different materials, but the material of the first metal layer 212 is the same as that of the tab 301. Welding with the same material can reduce the welding difficulty. Specifically, the first metal layer 212 can be a copper layer, and the second metal layer 213 can be an aluminum layer.

[0147] It should be noted that the material of the first connecting part 22 is the same as that of the second metal layer 213. For example, the first connecting part 22 and the second metal layer 213 of the second connecting part 21 can be an integral structure, so that the pole post 2 has a high degree of integrity, thereby reducing the contact resistance.

[0148] In some embodiments, such as Figure 17 As shown, the first metal layer 212 extends into the first connecting portion 22 at both ends in the first direction X. This arrangement serves several purposes: firstly, the extension of the first metal layer 212 into the first connecting portion 22 reduces the risk of the electrolyte inside the housing 20 contacting the second metal layer 213; secondly, when using nano-injection molding, the extension of the first metal layer 212 into the first connecting portion 22 also extends the sealing path of the first metal layer 212, making the seal more reliable during nano-injection molding; and thirdly, from the perspective of stamping the first metal layer 212 and the second metal layer 213, the extension of the first metal layer 212 into the first connecting portion 22 prevents delamination and cracking at the interface between the first metal layer 212 and the first connecting portion 22 due to stamping stress.

[0149] In at least one possible implementation, such as Figure 17 As shown, the first metal layer 212 extends towards the first connecting portion 22 at both ends in the first direction X to form a portion of the first wall 23 and a portion of the first connecting portion 22. The first metal layer 212 also extends towards the flange portion 26 at both ends in the third direction Y to form a portion of the second wall 24 and a portion of the flange portion 26. This improves the overall structural strength of the pole post 2 and reduces the risk of separation between the first metal layer 212 and the second metal layer 213.

[0150] In at least one embodiment, such as Figure 17As shown, in the first direction X, the distance between the end face of the first metal layer 212 and the end face of the corresponding first connecting portion 22 that is away from the second connecting portion 21 is L1, and the dimension of the first connecting portion 22 in the first direction X is L2.

[0151] In some embodiments, L1 satisfies: 5mm≤L1≤25mm. For example, L1 can be located in multiple intervals such as 5mm≤L1≤20mm, 5mm≤L1≤15mm, 15mm≤L1≤25mm, etc. Specifically, L1 = 5mm, 8mm, 10mm, 15mm, 18mm, 20mm or 25mm, or any value between the two mentioned above.

[0152] For example, the relationship between L1 and L2 satisfies: 70% ≤ L1 / L2 ≤ 90%. For instance, L1 / L2 can fall within multiple ranges such as 70% ≤ L1 / L2 ≤ 80%, 70% ≤ L1 / L2 ≤ 75%, 80% ≤ L1 / L2 ≤ 90%, etc. Specifically, L1 / L2 = 70%, 75%, 78%, 80%, 85%, 88%, or 90%, or any value between any two of the above. If L1 / L2 is too small, during laser welding of the first connection portion 22 and the electrical connector 200, phenomena such as bursting welds or incomplete soldering are likely to occur. If L1 / L2 is too large, it will cause the sealing path of the first metal layer 212 (e.g., copper layer) to be too short, thereby reducing the long-term sealing reliability of the top cover assembly 10 and affecting the safety performance of the battery cell 100.

[0153] It is understandable that if the amount of copper used is not considered, that is, if the cost of pole 2 is not considered, pole 2 can be processed with an integral copper-aluminum composite plate, that is, L1=0, that is, the first connecting part 22 also adopts a copper-aluminum composite plate structure.

[0154] In some embodiments, when the pole post 2 includes a first wall 23 and a second wall 24, the insulation structure between the pole post 2 and the cover plate may employ the first insulating member 3 and the second insulating member 4 described above.

[0155] In other embodiments, when the pole post 2 includes a first wall 23 and a second wall 24, the two first walls 23 and the two second walls 24 can be connected to each other. In this case, the structure of the pole post 2 can accommodate the sealing ring 5. Based on this, this embodiment provides a second insulating member 4 that is different from the first insulating member 3 and the second insulating member 4 described above.

[0156] For example, such as Figure 22 and Figure 23As shown, the first insulating member 3 is used to fix the pole post 2 and the top cover plate 1. That is, the pole post 2 is fixedly mounted on the top cover plate 1 through the first insulating member 3. When there is a large contact area between the pole post 2 and the first insulating member 3, the connection between the pole post 2 and the top cover plate 1 can have high reliability. For example, to facilitate the positioning of the first insulating member 3, as... Figure 24 As shown, the top cover plate 1 has a first shallow groove 13 on the side facing the first connecting part 22, and the bottom of the first insulating member 3 is placed in the first shallow groove 13.

[0157] For example, such as Figure 19 As shown, the first insulating member 3 includes a first insulating portion 31 and a second insulating portion 32 connected together. Wherein, as... Figure 23 As shown, the first insulating part 31 is disposed between the first connecting part 22 and the top cover plate 1, and is used for insulation and sealing between the top cover plate 1 and the first connecting part 22. The second insulating part 32 covers the circumferential sidewall of the first connecting part 22 to reduce the risk of short circuit between the circumferential sidewall of the first connecting part 22 and the top cover plate 1, thereby improving the insulation effect on the first connecting part 22.

[0158] In at least one possible implementation, the two first insulating portions 31 are connected into a whole by the second insulating portion 32, and the second insulating portion 32 also covers the end face of the two flange portions 26 facing away from the second connecting portion 21, so as to achieve insulation between the flange portions 26 and the top cover plate 1.

[0159] In some embodiments, such as Figure 22 As shown, the second insulating member 4 is disposed on the side of the top cover plate 1 opposite to the first connecting portion 22, that is, the second insulating member 4 is disposed on the side of the top cover plate 1 facing the electrode assembly 30. Figure 18 As shown, the second insulating member 4 is provided with a third through hole 41 corresponding to the first through hole 11, and the third through hole 41 extends through the thickness direction of the second insulating member 4. The second connecting part 21 passes through the first through hole 11 and the third through hole 41 in sequence to facilitate connection with the tab 301.

[0160] For example, such as Figure 19 and Figure 20 As shown, the first insulating member 3 includes a third insulating portion 36, a fourth insulating portion 37, and a fifth insulating portion 38. Wherein, as... Figure 23 As shown, the fourth insulating portion 37 and the fifth insulating portion 38 are both connected to the third insulating portion 36, making the third insulating portion 36, the fourth insulating portion 37, and the fifth insulating portion 38 an integral structure. The third insulating portion 36 is provided on the side of the top cover plate 1 opposite to the first connecting portion 22 and is used for insulation between the top cover plate 1 and the electrode tab 301. The fourth insulating portion 37 passes through the top cover plate 1 and connects to the second insulating portion 32, for example, as shown... Figure 18 As shown, the top cover plate 1 is provided with an injection hole 12 that is different from the first through hole 11, such as... Figure 23 As shown, the fourth insulating part 37 passes through the glue injection hole 12. The fifth insulating part 38 is provided between the hole wall of the first through hole 11 and the second connecting part 21 for insulating and sealing the second connecting part 21 and the top cover plate 1.

[0161] In at least one possible implementation, one end of the fourth insulating part 37 is connected to the third insulating part 36, and the other end of the fourth insulating part 37 is connected to the first insulating part 31, so that the first insulating member 3 is an integral structure, and can be obtained in a single manufacturing process. For example, the first insulating member 3 can be obtained by nano-injection molding.

[0162] It should be noted that by setting the injection hole 12, on the one hand, it is beneficial for the insulating material of the first insulating component 3 to be injected from the top surface of the top cover plate 1 to the bottom surface during injection molding, so that the material can flow and be injected simultaneously on the top and bottom surfaces of the top cover plate 1, which accelerates the flow speed of the insulating material, shortens the flow path of the material, improves the structural strength and bonding strength of the first insulating component 3, and makes the overall integrity higher; on the other hand, the fourth insulating part 37 of the first insulating component 3 after injection molding passes through the injection hole 12 and connects the second insulating part 32 and the third insulating part 36 located on the outside of the top cover plate 1, so as to facilitate a tight connection between the first insulating component 3 and the top cover plate 1 and the pole post 2, thereby effectively enhancing the sealing performance between the first insulating component 3 and the pole post 2 and the top cover plate 1, and improving the stability and reliability of the first insulating component 3 when used for sealing.

[0163] Optionally, a sealing ring 5 is also provided between the first insulating member 3 and the second insulating member 4. The sealing ring 5 is used to seal the gap between the electrode post 2 and the top cover plate 1. On the one hand, it reduces the risk of electrolyte leakage in the housing 20. On the other hand, it also prevents external water and gas from entering the housing 20 through the gap.

[0164] For example, such as Figure 23 As shown, the sealing ring 5 is fitted onto the pole post 2. The pole post 2, the first insulating part 31, the top cover plate 1, and the fifth insulating part 38 enclose a receiving cavity (not shown in the figure), and the sealing ring 5 is disposed in the receiving cavity. This arrangement allows the sealing ring 5 to withstand the pressure from the first insulating part 31, the fifth insulating part 38, and the pole post 2, reducing the risk of misalignment of the sealing ring 5. In some optional embodiments, the sealing ring 5 is fitted over the first wall 23 and the second wall 24.

[0165] Because the pressure during nano-injection molding is relatively high, the sealing ring 5 fitted on the pole post 2 is prone to misalignment. However, in this embodiment, an injection hole 12 is opened on the top cover plate 1. While integrally molding the first insulating part 3, it can also accommodate the setting of the sealing ring 5. This ensures that even if the sealing ring 5 is set, it will not form an obstruction. The plastic material can flow to both sides of the sealing ring, thereby forming the first insulating part 3. It can also reduce the risk of misalignment of the sealing ring 5 and improve the reliability and safety of the top cover assembly 10.

[0166] It should be noted that when the pole post 2 includes a first wall 23 and a second wall 24, the first wall 23 and the second wall 24 are used to abut against the sealing ring 5. Therefore, the fusible link structure should not be provided on the first wall 23 and the second wall 24. In view of this situation, this embodiment provides a pole post 2 in which the fusible link structure can be provided on the first connecting part 22.

[0167] For example, such as Figure 24 and Figure 25 As shown, a groove 222 is provided on the surface of the first connecting portion 22 facing away from the top cover plate 1. The groove 222 makes the thickness of the first connecting portion 22 smaller at the location where the groove 222 is provided, thus allowing this part to serve as a fusion structure. The position of the groove 222 satisfies the following: along the first direction X, the groove 222 is located on the side of the first welding area 221 facing the second connecting portion 21, so that the groove 222 does not occupy the area of ​​the first welding area 221, thereby ensuring the connection strength between the pole 2 and the electrical connector 200. In this embodiment, the groove 222 extends along the third direction Y, that is, the length direction of the groove 222 is the third direction Y, the width direction of the groove 222 is the first direction X, and the depth direction of the groove 222 is the second direction Z.

[0168] In some alternative embodiments, such as Figure 25 As shown, the two ends of the groove 222 extend to the two surfaces of the first connecting portion 22 in the third direction Y. This facilitates the processing and manufacturing of the groove 222 and also facilitates the smooth melting of the fusion structure.

[0169] For example, such as Figure 25 As shown, a second through hole 223 is provided on the bottom wall of the groove 222 along the second direction Z. By providing the second through hole 223, the width of the fusion structure is narrower, which facilitates the fusion of the fusion structure. In this embodiment, the through hole is located in the middle of the groove 222 in the third direction Y.

[0170] In some alternative embodiments, an insulating layer may be provided in the groove 222. For example, the first insulating member 3 has a portion disposed in the groove 222, such that the first insulating member 3 isolates the fusible structure and the electrical connector 200.

[0171] In at least one possible implementation, such as Figure 26 As shown, the surface of the pole post 2 facing away from the top cover plate 1 is also provided with a second shallow groove 27. The groove 222 is located at the bottom of the second shallow groove 27, and the flange 26 is part of the bottom of the second shallow groove 27. The part of the first connecting part 22 located between the groove 222 and the second connecting part 21 is also part of the bottom of the second shallow groove 27. By setting the second shallow groove 27, the flange 26 and the part of the first connecting part 22 located on the side of the groove 222 facing the second connecting part 21 are both lower than the first welding area 221 of the first connecting part 22. As a result, after the fusion structure melts, the flange 26 and the part of the first connecting part 22 other than the first welding area 221 will no longer contact the electrical connector 200, reducing the risk of short circuit.

[0172] In some alternative embodiments, such as Figure 15 As shown, the dimension of the first connecting part 22 in the third direction Y is W1, and the dimension of the top cover piece 1 in the third direction Y is H2. Figure 22 As shown, the first connecting part 22 has a dimension of H3 in the first direction X, the top cover plate 1 has a dimension of H4 in the first direction X, and the pole post 2 has a dimension of H5 in the first direction X.

[0173] In some embodiments, H2 satisfies: 14mm≤H2≤40mm. For example, H2 can be located in multiple intervals such as 14mm≤H2≤30mm, 14mm≤H2≤20mm, 30mm≤H2≤40mm, etc. Specifically, H2 = 14mm, 18mm, 20mm, 25mm, 30mm, 35mm, 40mm, etc., or any value between the two mentioned above.

[0174] In some embodiments, the relationship between W1 and H2 satisfies: 50% ≤ W1 / H2 ≤ 80%. W1 / H2 can be within multiple ranges such as 50% ≤ W1 / H2 ≤ 70%, 50% ≤ W1 / H2 ≤ 60%, and 60% ≤ W1 / H2 ≤ 80%. Specifically, W1 / H2 = 50%, 55%, 60%, 65%, 70%, 75%, 80%, or any value between any two of these. Through this setting, the value of W1 / H2 is within the specified range, ensuring that the proportion of the first connecting portion 22 on the top cover plate 1 in the third direction Y is neither too large nor too small. This ensures that the connection area between the pole post 2 and the electrical connector 200 is maintained without affecting the structural strength of the top cover plate 1. If the value of W1 / H2 is greater than 80%, the structural strength of the top cover plate 1 in the area where the first connecting portion 22 is located will be significantly reduced, posing a risk of breakage. If the value of W1 / H2 is less than 50%, the width of the first connecting part 22 will be smaller, and the connection strength with the electrical connector 200 will be lower.

[0175] In some embodiments, H3 satisfies: 7mm≤H3≤28mm. For example, H3 can be located in multiple intervals such as 7mm≤H3≤25mm, 10mm≤H3≤20mm, 20mm≤H3≤28mm, etc. Specifically, H3 = 7mm, 8mm, 10mm, 15mm, 20mm, 25mm, 28mm, etc., or any value between the two mentioned above.

[0176] In some embodiments, H5 satisfies: 35mm≤H5≤80mm. For example, H5 can be located in multiple intervals such as 35mm≤H5≤60mm, 50mm≤H5≤80mm, 60mm≤H5≤80mm, etc. Specifically, H5 = 35mm, 50mm, 55mm, 60mm, 70mm, 75mm, 80mm, etc., or any value between the two mentioned above.

[0177] In some embodiments, the relationship between H3 and H4 satisfies: 3% ≤ H3 / H4 ≤ 10%, where H3 / H4 can be within multiple intervals such as 3% ≤ H3 / H4 ≤ 10%, 3% ≤ H3 / H4 ≤ 8%, 6% ≤ H3 / H4 ≤ 10%, etc. Specifically, H3 / H4 = 3%, 5%, 6%, 7%, 8%, 9%, 10%, etc., or any value between any two of the above. Through the above settings, the value of H3 / H4 is within the range, ensuring that the proportion of the first connecting portion 22 on the top cover plate 1 in the first direction X is neither too large nor too small, thus guaranteeing the distribution of the two pole posts 2. If the value of H3 / H4 is greater than 10%, the structural strength of the top cover plate 1 in the area where the first connecting portion 22 is located will be greatly reduced, posing a risk of breakage. If the value of H3 / H4 is less than 3%, the length of the first connecting portion 22 will be relatively small, resulting in lower connection strength with the electrical connector 200.

[0178] In some embodiments, the relationship between H3 and H5 satisfies: 20% ≤ H3 / H5 ≤ 35%. H3 / H5 can be located within multiple intervals such as 20% ≤ H3 / H5 ≤ 35%, 20% ≤ H3 / H5 ≤ 30%, 25% ≤ H3 / H5 ≤ 35%, etc. Specifically, H3 / H5 = 20%, 25%, 28%, 30%, 31%, 32%, 35%, etc., or any value between any two of the above. Through the above settings, the value of H3 / H5 is within the range, allowing the first connecting portion 22 to have a relatively large proportion in the pole post 2 in the first direction X. The proportion of the first connecting portion 22 on the top cover plate 1 is neither too large nor too small, ensuring both the connection area between the pole post 2 and the electrical connector 200 and the connection strength between the second connecting portion 21 and the tab 301. If the value of W1 / H2 is greater than 30%, the size of the first connecting part 22 in the first direction X will be too large, and the size of the second connecting part 21 will be too small, which will affect the connection strength between the second connecting part 21 and the tab 301. If the value of W1 / H2 is less than 20%, the length of the first connecting part 22 will be too small, and the connection strength with the electrical connector 200 will be low.

[0179] In some embodiments, such as Figure 1 and Figure 3 As shown, along the second direction Z, the projection of the second connecting portion 21 and the projection of the electrical connector 200 can partially overlap. With this arrangement, the electrical connector 200 covers the second connecting portion 21 along the second direction Z.

[0180] In other embodiments, such as Figure 21 and Figure 22 As shown, along the second direction Z, the projection of the second connecting portion 21 and the projection of the electrical connector 200 may not coincide. With this arrangement, the electrical connector 200 has a clearance opening along the second direction Z to expose the second connecting portion 21, allowing the second connecting portion 21 to be exposed and facilitating heat dissipation. For example, as... Figure 21 As shown, the electrical connector 200 is in the shape of a horizontal "I".

[0181] In some alternative embodiments, such as Figure 5 As shown, the top cover plate 1 may also be provided with a pressure relief mechanism 6 for releasing internal pressure when the internal pressure or temperature of the battery cell 100 reaches a threshold. The surface of the pressure relief mechanism 6 facing the outer side of the casing is provided with a protective layer (not shown in the figure) to protect the pressure relief mechanism 6. By providing a pressure relief mechanism 6 on the top cover plate 1, thermal runaway of the battery cell 100 is less likely to occur. Optionally, the pressure relief mechanism 6 can be an explosion-proof valve.

[0182] Obviously, the above embodiments of this application are merely examples for clear illustration and are not intended to limit the implementation of this application. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.

Claims

1. A top cover assembly, characterized in that, include: The top cover plate (1) has a first through hole (11) extending along the second direction (Z); A pole post (2) is disposed on the top cover plate (1). The pole post (2) includes at least one second connecting part (21) and at least two first connecting parts (22) arranged along a first direction (X). Each second connecting part (21) is connected to two adjacent first connecting parts (22). The two adjacent first connecting parts (22) are located on one side of the top cover plate (1) and are used to connect to the same electrical connector (200). At least a portion of the second connecting part (21) passes through the first through hole (11) and is used to connect to the electrode tab (301). The first direction (X) is the length direction of the top cover plate (1), and the second direction (Z) is the thickness direction of the top cover plate (1). Each of the first connecting parts (22) is provided with a first welding area (221), which is used to connect with the electrical connector (200). The first welding areas (221) of two adjacent first connecting parts (22) are spaced apart along the first direction (X).

2. The top cover assembly according to claim 1, characterized in that, The second connecting part (21) is provided with a second welding area (211), which is used to connect with the electrode (301). Along the second direction (Z), there is a height difference between each of the first welding area (221) and the second welding area (211).

3. The top cover assembly according to claim 2, characterized in that, Along the first direction (X), a first wall (23) is connected to each of the opposite sides of the second connecting part (21), and the end of each first wall (23) away from the second connecting part (21) is connected to the corresponding first connecting part (22).

4. The top cover assembly according to claim 3, characterized in that: Along the third direction (Y), a second wall (24) is connected to each of the opposite sides of the second connecting part (21), and along the first direction (X), each second wall (24) is connected between two adjacent first connecting parts (22); the third direction (Y) is the width direction of the top cover plate (1); Along the circumference of the second connecting portion (21), each of the first walls (23) is connected between two adjacent second walls (24), and the two first walls (23), the two second walls (24) and the second connecting portion (21) together form a recess (25).

5. The top cover assembly according to claim 4, characterized in that: Each of the second walls (24) is provided with a flange (26), which is connected to one end face of the second wall (24) along the second direction (Z) and extends in the third direction (Y) away from the second connecting part (21); along the third direction (Y), the end face of the flange (26) is flush with the end faces of the two adjacent first connecting parts (22).

6. The top cover assembly according to claim 5, characterized in that: The first connecting part (22) has a dimension of W1 in the third direction (Y), and the flange part (26) has a dimension of W2 in the third direction (Y), wherein: 7mm≤W1≤32mm; and / or, 1mm≤W2≤3mm; and / or, 1%≤W2 / W1≤20%.

7. The top cover assembly according to claim 5, characterized in that, Along the second direction (Z), the second connecting portion (21) includes a first metal layer (212) and a second metal layer (213) stacked together; the surface of the first metal layer (212) facing away from the second metal layer (213) is provided with a surface for welding the tab (301); The first metal layer (212) extends into the first connecting portion (22) at both ends in the first direction (X).

8. The top cover assembly according to claim 7, characterized in that, In the first direction (X), the distance between the end face of the first metal layer (212) and the end face of the corresponding first connecting portion (22) away from the second connecting portion (21) is L1; the dimension of the first connecting portion (22) in the first direction (X) is L2; 5mm≤L1≤25mm; and / or, 70%≤L1 / L2≤90%.

9. The top cover assembly according to claim 5, characterized in that, The first connecting part (22) has a groove (222) on the side surface away from the top cover plate (1). Along the first direction (X), the groove (222) is located on the side of the first welding area (221) facing the second connecting part (21) and extends along the third direction (Y). Along the second direction (Z), the bottom wall of the groove (222) is provided with a through second hole (223).

10. The top cover assembly according to claim 5, characterized in that, Also includes: The first insulating component (3) is fixedly connected to the pole post (2) and the top cover plate (1). The first insulating component (3) includes a first insulating part (31) and a second insulating part (32) connected together. The first insulating part (31) is disposed between the first connecting part (22) and the top cover plate (1). The second insulating part (32) covers the circumferential sidewall of the first connecting part (22). The first insulating component (3) also includes a third insulating part (36), and a fourth insulating part (37) and a fifth insulating part (38) connected to the third insulating part (36). The third insulating part (36) is disposed on the side of the top cover plate (1) away from the first connecting part (22). The fourth insulating part (37) passes through the top cover plate (1) and the second insulating part (32) and is connected. The fifth insulating part (38) is disposed between the hole wall of the first through hole (11) and the second connecting part (21). The second insulating member (4) is provided on the side of the top cover plate (1) away from the first connecting part (22). The second insulating member (4) is provided with a third through hole (41) corresponding to the first through hole (11). The third through hole (41) penetrates the thickness direction of the second insulating member (4). The second connecting part (21) passes through the first through hole (11) and the third through hole (41) in sequence. A sealing ring (5) is fitted onto the pole post (2). The pole post (2), the first insulating part (31), the top cover plate (1), and the fifth insulating part (38) surround and form a receiving cavity. The sealing ring (5) is disposed in the receiving cavity.

11. The top cover assembly according to claim 3, characterized in that, The first insulating member (3) includes a first insulating part (31), a sixth insulating part (33) and a seventh insulating part (34) connected together. The first insulating part (31) is disposed between the first connecting part (22) and the top cover plate (1). The sixth insulating part (33) is disposed between the hole wall of the first through hole (11) and the second connecting part (21). The seventh insulating part (34) is disposed on the side of the top cover plate (1) away from the first connecting part (22). On a virtual plane perpendicular to the second direction (Z), the orthographic projection of the seventh insulating part (34) overlaps with the orthographic projection of the top cover plate (1). The second insulating member (4) is provided on the side of the top cover plate (1) away from the first connecting part (22). The second insulating member (4) is provided with a third through hole (41) corresponding to the first through hole (11). The third through hole (41) penetrates the thickness direction of the second insulating member (4). The second connecting part (21) passes through the first through hole (11) and the third through hole (41) in sequence. The circumferential outer edge of the seventh insulating part (34) is a first inclined structure (341). The second insulating member (4) has a second inclined structure (45) that matches the first inclined structure (341). The second inclined structure (45) abuts against the first inclined structure (341).

12. The top cover assembly according to claim 3, characterized in that, The first wall (23) is a fused part, and along the third direction (Y), the size of the first wall (23) is smaller than the size of the first connecting part (22) and the second connecting part (21), and the third direction (Y) is the width direction of the top cover plate (1); And / or, along the second direction (Z), the second connecting portion (21) is recessed on the side surface near the first connecting portion (22), and the second connecting portion (21) is correspondingly protruded on the side surface away from the first connecting portion (22) to form a protrusion (214), the protrusion (214) being provided in the second welding area (211), and there are multiple protrusions.

13. The top cover assembly according to any one of claims 1-12, characterized in that, The top cover assembly also includes a first insulating member (3), which is fixedly connected to the pole post (2) and the top cover plate (1). The surfaces of the pole post (2) and the first insulating member (3) that are in contact are provided with a first nanopore, and the first insulating member (3) is at least partially embedded in the first nanopore; and / or, The surface of the top cover (1) that contacts the first insulating member (3) is provided with a second nanopore, and the first insulating member (3) is at least partially embedded in the second nanopore.

14. The top cover assembly according to any one of claims 1-12, characterized in that, The first connecting part (22) has a dimension of W1 in the third direction (Y), the top cover plate (1) has a dimension of H2 in the third direction (Y), the first connecting part (22) has a dimension of H3 in the first direction (X), the top cover plate (1) has a dimension of H4 in the first direction (X), and the pole post (2) has a dimension of H5 in the first direction (X). 7mm≤W1≤32mm; and / or, 14mm≤H2≤40mm; and / or, 50%≤W1 / H2≤80%; and / or, 7mm≤H3≤28mm; and / or, 35mm≤H5≤80mm; and / or, 3%≤H3 / H4≤10%; and / or, 20%≤H3 / H5≤35%.

15. A single battery cell, characterized in that, include: The housing (20) has an opening; An electrode assembly (30) having tabs (301) is housed within the housing (20); The top cover assembly as described in any one of claims 1-14 is disposed over the opening of the housing (20).

16. A battery, characterized in that, It includes multiple electrical connectors (200) and multiple battery cells as described in claim 15, with two adjacent battery cells connected by one of the electrical connectors (200); The two adjacent first connection portions (22) of the pole post (2) are welded to the same electrical connector (200), and the weld marks formed by the welding of the two first connection portions (22) to the electrical connector (200) are spaced apart along the first direction (X).

17. The battery according to claim 16, characterized in that, Along the second direction (Z), the projection of the second connecting part (21) and the projection of the electrical connector (200) do not coincide or partially coincide.

18. A battery, characterized in that, The device includes multiple electrical connectors (200) and multiple battery cells, with adjacent battery cells connected by one of the electrical connectors (200); each battery cell includes: a housing (20) having an opening; an electrode assembly (30) having tabs (301), the electrode assembly (30) being housed within the housing (20); and a top cover assembly covering the opening of the housing (20), the top cover assembly including: The top cover plate (1) has a first through hole (11) extending along the second direction (Z); A pole post (2) is disposed on the top cover plate (1). The pole post (2) includes at least one second connecting part (21) and at least two first connecting parts (22) arranged along a first direction (X). Each second connecting part (21) is connected to two adjacent first connecting parts (22). The two adjacent first connecting parts (22) are located on one side of the top cover plate (1) and are used to connect to the same electrical connector (200). At least a portion of the second connecting part (21) passes through the first through hole (11) and is used to connect to the electrode tab (301). The first direction (X) is the length direction of the top cover plate (1), and the second direction (Z) is the thickness direction of the top cover plate (1). Along the first direction (X), the weld marks formed by welding two adjacent first connecting parts (22) to the electrical connector (200) are spaced apart.

19. An electrical appliance, characterized in that, The device may include a battery cell as described in claim 15; or the device may include a battery as described in any one of claims 16-18.

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