Top cover assembly, battery monomer, battery and electric device

Abstract

The application provides a top cover assembly, a battery monomer, a battery and an electric device, and relates to the technical field of batteries. The top cover assembly comprises a top cover sheet, a first insulating piece, a support piece and a pole. The first insulating piece is arranged on one side surface of the top cover sheet in a third direction. The support piece is arranged on one side surface of the first insulating piece away from the top cover sheet, and is used for supporting a tab during welding. The pole is arranged on the top cover sheet and is used for being connected with the tab. When the tab and the pole are connected, the support piece is supported below the tab, sufficient support is provided for a welding tool located above the tab, the pressure distribution of the welding tool is uniform, the inclination of the welding tool and the local deformation of the tab are reduced, the positioning accuracy of the welding tool is improved, the laser leakage during welding is avoided, the welding effect is improved, the situation that the tab is pressed and deformed is avoided, and the conductivity and service life of the battery are improved.

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 structure design, the direct connection between the tab and the terminal post can achieve efficient current transmission, making it one of the important research directions in the battery field. In related technologies, the terminal post has a tab connection portion that connects to the tab. When welding the tab connection portion to the tab, a welding fixture can be used to position the surface of the tab away from the tab connection portion, thereby welding the tab and the terminal post's tab connection portion together.

[0003] However, in existing technologies, for relatively thin battery cells, the width design space of the top cover assembly is limited, resulting in a relatively small width for the tab connection portion of the terminal post. This means that the welding fixture cannot be directly pressed onto the top of the tab connection portion, but can only be pressed onto the outer periphery. In this case, if there is no support under the tab, the welding fixture is prone to uneven pressure distribution and insufficient positioning accuracy, leading to poor welding quality, which in turn affects the battery's conductivity and lifespan. Furthermore, the lack of support under the tab can easily cause it to deform under pressure, further affecting the battery's conductivity. Utility Model Content

[0004] 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 in the prior art where poor welding quality easily occurs when connecting the tabs and terminals in the top cover assembly, affecting the conductivity and service life of the battery.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0006] In a first aspect, this application provides a top cover assembly, including a top cover sheet, a first insulating member, a support member, and a pole post. The first insulating member is disposed on one side surface of the top cover sheet along a third direction; the support member is disposed on the side surface of the first insulating member opposite to the top cover sheet; the pole post is disposed on the top cover sheet and is used to connect with a tab; the support member is at least partially disposed around the periphery of the pole post and is used to support part of the tab during tab welding.

[0007] In one or more embodiments of this application, the support member and the first insulating member are integrally formed, and the support member protrudes from the surface of the first insulating member.

[0008] In one or more embodiments of this application, the pole post includes at least two first connecting portions and at least one second connecting portion. Each second connecting portion is connected to two adjacent first connecting portions. The at least two first connecting portions are arranged at intervals along a second direction. The second connecting portion is located on the side of the top cover plate away from the first insulating member and is used to connect with an electrical connector. The top cover plate is provided with a first through hole, and the first insulating member is provided with a second through hole. At least a portion of the first connecting portion passes through the first through hole and the second through hole and is used to connect with the electrode tab.

[0009] The support member includes a first part, which is disposed along a second direction between a second through hole and one side edge of a first insulating member; wherein the second direction and a third direction intersect.

[0010] In one or more embodiments of this application, the support member further includes a second part, which is disposed along a second direction between the second through hole and the other edge of the first insulating member, and is disposed opposite to the first part. Along a third direction, the second through hole penetrates the support member.

[0011] In one or more embodiments of this application, at least two second through holes are provided at intervals along the second direction, and each first connecting part is correspondingly disposed in one second through hole. Along the second direction, two second parts located between two adjacent second through holes are provided at intervals; or, two second parts located between two adjacent second through holes are connected as one unit.

[0012] In one or more embodiments of this application, the support further includes a third part, which is disposed on one side of the second through hole along the first direction; and / or,

[0013] The support also includes a fourth part, which is located on the other side of the second through hole along the first direction, wherein the first direction, the second direction and the third direction intersect each other.

[0014] In one or more embodiments of this application, along a third direction, the support member has a support surface, the first connecting portion has a first electrical connection surface, the first electrical connection surface is connected to the electrode tab, and the support surface and the first electrical connection surface are on the same plane.

[0015] In one or more embodiments of this application, along a third direction, the support member has a support surface, the first connecting portion has a first electrical connection surface, the first electrical connection surface is connected to the electrode tab, and the first electrical connection surface extends beyond the support surface.

[0016] In one or more embodiments of this application, along a third direction, a gap is formed between the dummy plane where the first electrical connection surface is located and the support surface, the gap being used to accommodate at least a portion of the third insulating member, the third insulating member being used to cover the outer surface of the electrode assembly.

[0017] In one or more embodiments of this application, a first fixing part is provided on the surface of the first insulating member away from the top cover sheet. Along a third direction, the first fixing part has a fixing surface, and the fixing surface and the supporting surface are on the same plane.

[0018] In one or more embodiments of this application, the support member and the first fixing part are connected as an integral structure by a connecting part, wherein, along the second direction, the width of the connecting part is smaller than the width of the first fixing part and smaller than the width of the support member; and / or,

[0019] The electrode includes two poles spaced apart along a first direction, each pole including two first connecting portions. The first insulating member includes two second through holes spaced apart along a second direction, each first connecting portion corresponding to a second through hole. The support member includes two sets spaced apart along the first direction, each set including two support members along the second direction, each support member corresponding to a second through hole. Along the first direction, adjacent sets of support members are connected to form an integral structure by connecting portions, and along the second direction, the width of the connecting portion is smaller than the width of each support member. The first direction, the second direction, and the third direction intersect each other; and / or,

[0020] The first fixing part includes four parts, which are respectively located at the four corners of the first insulating member; and / or,

[0021] The area of ​​the first fixing part projected onto the surface of the first insulating member is smaller than the area of ​​the support member projected onto the surface of the first insulating member.

[0022] In one or more embodiments of this application, a second fixing part is provided on the surface of the first insulating member facing the top cover sheet. The first insulating member is fixed to the top cover sheet by the second fixing part. On a dummy plane perpendicular to a third direction, the orthographic projection of the second fixing part does not overlap with the orthographic projection of the first fixing part and the orthographic projection of the support member.

[0023] In one or more embodiments of this application, along a third direction, the distance between the first electrical connection surface and the support surface is d, which satisfies: 0.05mm≤d≤0.25mm.

[0024] In one or more embodiments of this application, the support is arranged circumferentially around the second through hole.

[0025] In one or more embodiments of this application, along the second direction, the edge of the first part away from the second through hole is aligned with the edge of the first insulating member.

[0026] In one or more embodiments of this application, along a third direction, the first connecting portion has a first electrical connection surface and a first stepped surface, the first electrical connection surface protrudes from the first stepped surface, a side wall surface is connected between the first electrical connection surface and the first stepped surface, and the support extends to the first stepped surface and abuts against the side wall surface.

[0027] In one or more embodiments of this application, it further includes: a second insulating member, which is fixedly connected to the pole post and the top cover plate. The second insulating member includes a first insulating part, a second insulating part and a third insulating part connected to each other. The first insulating part is disposed on the side of the top cover plate facing the first insulating member. The second insulating part is disposed between the hole wall of the first through hole and the first connecting part of the pole post. The third insulating part is disposed on the side of the top cover plate facing away from the first insulating member. On a dummy plane perpendicular to the third direction, the orthographic projection of the first insulating part overlaps with the orthographic projection of the top cover plate.

[0028] The surface of the first insulating member facing the top cover plate is recessed to form a groove, and the surface facing away from the top cover plate is correspondingly raised to form a support member. The second through hole penetrates the bottom of the groove, and the first insulating part is accommodated in the groove and at least abuts against the bottom of the groove.

[0029] In one or more embodiments of this application, along the second direction, the minimum distance between the edge of the support member and the wall of the second through hole is w1, satisfying: 1mm ≤ w1 ≤ 10mm; and / or,

[0030] Along the first direction, the minimum distance between the edge of the support and the wall of the second through hole is w2, satisfying: 1mm ≤ w2 ≤ 10mm, wherein the first direction, the second direction, and the third direction intersect each other; and / or,

[0031] Along the second direction, the width of the second through hole is w3, and the maximum width of the top cover plate is w4, satisfying: 5% ≤ w3 / w4 ≤ 30%; and / or,

[0032] Along the second direction, the width of the second through hole is w3, satisfying: 3mm ≤ w3 ≤ 15mm; and / or,

[0033] Along the second direction, the maximum width of the top cover is w4, and along the first direction, the maximum length of the top cover is w5, satisfying: 7% ≤ w4 / w5 ≤ 35%.

[0034] Secondly, this application also provides a battery cell, including: a top cover assembly, a housing, and an electrode assembly as described in any of the first aspects, wherein the electrode assembly is housed within the housing, the electrode assembly extends into tabs, some of the tabs are connected to the terminal posts, and some of the tabs are supported by a support member.

[0035] In one or more embodiments of this application, it further includes: a third insulating member, the third insulating member including a first covering portion, the first covering portion covering the end face of the electrode assembly facing the top cover assembly, and the first covering portion having a third through hole, the first connecting portion passing through the third through hole and connecting to the electrode tab; at least a portion of the first covering portion is disposed between the support member and the electrode tab.

[0036] In one or more embodiments of this application, the surface of the first covering portion facing the electrode tab is on the same plane as the first electrical connection surface of the first connecting portion; and / or,

[0037] Along the third direction, the distance between the first electrical connection surface of the first connection portion and the support surface of the support member is consistent with the thickness of the first covering portion.

[0038] In one or more embodiments of this application, the electrode tab is welded to the first connecting portion to form a welded portion, and along the second direction, the end of the electrode tab is located between the welded portion and the edge of the support member; and / or,

[0039] Along the second direction, the end of the electrode extends beyond the edge of the support, wherein the second direction intersects with the third direction.

[0040] Thirdly, this application also provides a battery comprising the battery cell described in any of the second aspects.

[0041] Fourthly, this application also provides an electrical device, including a battery cell as described in any of the second aspects or a battery as described in the third aspect.

[0042] Based on the above technical solution, the top cover assembly, battery cell, battery, and power device of this application have at least the following beneficial technical effects:

[0043] The top cover assembly provided in this application embodiment has a support member disposed on the surface of the first insulating member away from the top cover sheet. The support member is disposed at least partially along the periphery of the electrode post. When the electrode tab and the electrode post are connected, the support member is supported below the electrode tab, providing sufficient support for the welding fixture located above the electrode tab. This results in a uniform pressure distribution on the welding fixture, reduces the tilting of the welding fixture and local deformation of the electrode tab, improves the positioning accuracy of the welding fixture, avoids laser leakage during welding, and thus improves the welding effect. At the same time, it avoids the electrode tab being deformed by pressure, thereby improving the conductivity and service life of the battery. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 A schematic diagram of the connection method between the top cover assembly and the electrode assembly during welding, provided for related technologies.

[0046] Figure 2 for Figure 1 AA section view.

[0047] Figure 3 for Figure 2 Enlarged view of point A in the middle.

[0048] Figure 4 This is a three-dimensional structural diagram of a battery cell provided in an embodiment of this application.

[0049] Figure 5 This is a schematic diagram of the planar structure of a battery cell provided in an embodiment of this application.

[0050] Figure 6 for Figure 5 CC cross-section view.

[0051] Figure 7 This is a three-dimensional structural diagram of the top cover assembly provided in an embodiment of this application.

[0052] Figure 8 This is a schematic diagram of the exploded disassembly structure of the top cover assembly provided in an embodiment of this application.

[0053] Figure 9 This is a three-dimensional structural diagram of the first insulating element in the top cover assembly provided in an embodiment of this application.

[0054] Figure 10 This is an exploded structural diagram of the top cover assembly provided in an embodiment of this application.

[0055] Figure 11 This is a schematic diagram of the planar structure of the top cover assembly provided in an embodiment of this application.

[0056] Figure 12 for Figure 11 Cross-sectional view of the middle section (BB).

[0057] Figure 13 This is a schematic diagram illustrating the connection method between the top cover assembly and the third insulating component provided in an embodiment of this application.

[0058] Figure 14 This is an exploded structural diagram of the top cover assembly and the third insulating component provided in an embodiment of this application.

[0059] Figure 15 This is a schematic diagram of the connection method between the top cover assembly and the electrode assembly during welding, as provided in the embodiments of this application.

[0060] In the figure: 11-First insulating component; 12-Top cover plate; 13-Second insulating component; 20-Pole post; 21-First connecting part; 22-Second connecting part; 23-First stepped surface; 100-Top cover assembly; 111-Support component; 112-First fixing part; 113-Second through hole; 114-Connecting part; 115-Second fixing part; 116-Groove; 121-First through hole; 130-Third insulating part; 131-First insulating part; 132-Second insulating part; 200 - Electrode assembly; 201 - Tab; 203 - Gap; 210 - First electrical connection surface; 211 - Side wall surface; 220 - Second electrical connection surface; 300 - Housing; 400 - Welding fixture; 500 - Third insulating component; 501 - First covering part; 502 - Third through hole; 503 - Second covering part; 1110 - Support surface; 1111 - First part; 1112 - Second part; 1113 - Third part; 1114 - Fourth part; 1121 - Fixing surface. Detailed Implementation

[0061] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0062] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0063] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0064] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0065] like Figures 1 to 3 As shown, Figures 1 to 3This diagram illustrates the connection structure of the top cover assembly and electrode assembly during welding, as provided in the related technology. In the related technology, the battery cell includes a housing, an electrode assembly 200, and a top cover assembly 100. The top cover assembly 100 typically consists of a top cover sheet 12, electrode posts 20, and a first insulating member 11. The first insulating member 11 is disposed on the surface of the top cover sheet 12 facing the interior of the housing, and is used to insulate the inner surface of the top cover sheet 12 and the electrode assembly 200. A tab 201 extends from the side of the electrode assembly 200. The electrode post 20 has three parts in the width direction of the top cover sheet 12: a second connecting part located in the middle and two first connecting parts located on either side of the second connecting part. The second connecting part is connected to the first connecting parts on both sides, and is used for welding with electrical connectors. The first connecting parts are used for welding with the tabs 201 of the electrode assembly 200. When the tabs of the electrode assembly 200 and the electrode post 20 are welded, the tabs 201 of the electrode assembly 200 are laid flat above the first connecting parts, as shown... Figure 3 As shown, there is a gap 203 between the tab 201 and the first insulating component 11. When the first connecting part and the tab 201 are welded, due to the limited size of the first connecting part, the welding fixture 400 is pressed onto the outer periphery of the first connecting part. At this time, there is no support under the tab 201, and the welding fixture 400 is prone to uneven pressure distribution and insufficient positioning accuracy, resulting in poor welding quality between the first connecting part and the tab 201, which in turn affects the conductivity and service life of the battery. At the same time, the lack of support under the tab 201 also makes it easy for the tab 201 to be deformed, further affecting the conductivity of the battery.

[0066] Based on the above considerations, in order to solve the technical problem in the prior art where poor welding quality easily occurs when connecting the tabs and terminals in the top cover assembly, affecting the conductivity and lifespan of the battery, this application provides an electrical device, a battery, a battery cell, and a top cover assembly.

[0067] 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 fixed 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.

[0068] 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 is installed inside the vehicle, and the battery can be located at the bottom, front, or rear of the vehicle. The battery can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor. The controller controls the battery to supply power to the motor, for example, to meet the power needs of starting, navigation, and driving the vehicle. The battery can not only serve as the vehicle's operating power source but also as its driving power source, replacing or partially replacing gasoline or natural gas to provide driving power to the vehicle.

[0069] The aforementioned battery can be a battery pack or a battery module. When the battery is a battery pack, the battery pack specifically includes a battery management system (BMS) and multiple battery cells. These battery cells can be electrically connected in series, parallel, or a combination of both, and communicate with the battery management system, which controls and monitors the operating status of each battery cell. Alternatively, multiple battery cells can first be combined with a module management system to form a battery module, and then these battery modules can be electrically connected in series, parallel, or a combination of both, together with the battery management system to form a battery pack.

[0070] Multiple battery cells can be mounted on supporting structures such as housings, frames, and brackets. Electrical connections between battery cells and between battery cells and the battery management system can be established via electrical connectors, which can be busbars. Alternatively, battery cells can be electrically connected by plugging in their respective terminals. For example, between two adjacent battery cells, one battery cell has a slot on its terminal, and the other battery cell has a corresponding insert on its terminal. The insert is inserted into the slot to achieve electrical connection. Therefore, for one battery cell, the aforementioned electrical connector can be the terminal of another battery cell. Similarly, battery cells and the battery management system can also be electrically connected by plugging in each other, which will not be elaborated further here.

[0071] The aforementioned battery cell can be a secondary battery or a primary battery, or it can 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.

[0072] A battery cell refers to the smallest unit that makes up a battery. As one embodiment of a battery cell, please refer to... Figure 4 , Figure 5 , Figure 6The battery cell includes a housing 300, an electrode assembly 200, a top cover assembly 100, and other functional components. The housing 300 has an opening at at least one end, and the top cover assembly 100 covers the opening of the housing 300 to isolate the internal environment of the battery cell from the external environment. The housing 300 has an internal cavity to accommodate the electrode assembly 200. The housing 300 is a component used to cooperate with the top cover assembly 100 to form the internal environment of the battery cell, wherein the formed internal environment can accommodate the electrode assembly 200, electrolyte, and other components. The housing 300 and the top cover assembly 100 can be independent components. An opening can be provided on the housing 300, and the top cover assembly 100 closes the opening to form the internal environment of the battery cell. The housing 300 can have various shapes and sizes, such as cylindrical, cuboid, hexagonal prism, etc. Specifically, the shape of the housing 300 can be determined according to the specific shape and size of the electrode assembly 200. The shell 300 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.

[0073] As one embodiment of an electrode assembly, electrode assembly 200 is a component in a battery cell that undergoes an electrochemical reaction with the electrolyte. The housing 300 may contain one or more electrode assemblies 200. The electrode assembly 200 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, 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, while the portions of the positive and negative electrode plates without active material each constitute a tab. The positive and negative tabs can be located together at one end of the main body or at opposite ends of the main body.

[0074] In some embodiments, each electrode assembly 200 extends a positive electrode tab and a negative electrode tab to the end face of the top cover assembly 100, respectively. During the charging and discharging process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the electrode tabs are connected to the terminal post 20 to form a current loop.

[0075] In the embodiments of this application, such as Figure 6As shown, the housing 300 includes two sets of electrode assemblies 200, each set containing one electrode assembly 200. The two sets of electrode assemblies 200 are arranged side-by-side along the thickness direction of the housing 300. The two sets of positive electrode tabs of the two sets of electrode assemblies 200 are positioned opposite each other as positive electrodes, and the two sets of negative electrode tabs of the two sets of electrode assemblies 200 are positioned 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 300. In some other embodiments, the housing 300 may include at least two sets of electrode assemblies 200. Each set of electrode assemblies 200 may consist of one electrode assembly 200 or multiple electrode assemblies 200; this is not limited here. When each set of electrode assemblies 200 includes multiple electrode assemblies 200, the positive electrode tabs of each electrode assembly 200 are brought together to form a set of positive electrode tabs, and the negative electrode tabs are brought together to form a set of negative electrode tabs.

[0076] Before the electrode assembly 200 is installed into the housing 300, the electrode tabs 201 of the electrode assembly 200 are usually assembled with the top cover assembly 100, for example, the electrode post 20 of the top cover assembly 100 is welded to the electrode tabs 201 of the electrode assembly 200, and then the electrode assembly 200 is installed into the housing 300.

[0077] The first direction X, the second direction Y, and the third direction Z disclosed in this application intersect each other. In some embodiments, the first direction X, the second direction Y, and the third direction Z are perpendicular to each other. In some embodiments, the first direction X may be the length direction of the housing 300, i.e., the length direction of the top cover assembly 100 or the length direction of the electrode assembly 200; the second direction Y may be the thickness direction of the housing 300, i.e., the width direction of the top cover assembly 100 or the thickness direction of the electrode assembly 200; and the third direction Z may be the height direction of the housing 300, i.e., the height direction of the electrode assembly 200 or the thickness direction of the top cover sheet 12.

[0078] The structure of the top cover assembly 100 is described below.

[0079] As one embodiment of the top cover assembly 100, please refer to Figure 7 and Figure 8The top cover assembly 100 includes a top cover sheet 12, a first insulating member 11, a support member 111, an electrode post 20, and a second insulating member 13. The top cover sheet 12 covers the opening of the housing 300. The top cover sheet 12 can be made of a material with certain hardness and strength (such as aluminum alloy or aluminum), so that the top cover sheet 12 is not easily deformed under pressure or impact, allowing the battery cell to have higher structural strength and improved safety performance. The material of the top cover sheet 12 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. The top cover sheet 12 has a first through hole 121 that allows a portion of the electrode post 20 to pass through. The first through hole 121 extends through the thickness direction of the top cover sheet 12 to allow a portion of the electrode post 20 to pass through and connect with the tab 201 of the electrode assembly 200.

[0080] In some embodiments, such as Figure 11 As shown, along the second direction Y, the maximum width of the top cover plate 12 is w4, and along the first direction X, the maximum length of the top cover plate 12 is w5, satisfying: 7% ≤ w4 / w5 ≤ 35%. For example, w4 / w5 can be located within multiple intervals such as: 7% ≤ w4 / w5 ≤ 30%, 8% ≤ w4 / w5 ≤ 30%, 9% ≤ w4 / w5 ≤ 25%, 10% ≤ w4 / w5 ≤ 25%, etc. Specifically, w4 / w5 = 7%, 8%, 9%, 10%, 11%, 12%, 15%, 17%, 19%, 21%, 23%, 25%, 26%, 27%, 29%, 30%, 33%, 35%, etc., including but not limited to the values ​​listed above. Other values ​​between any two of the above are still applicable. For example, w4 / w5 can be 21% to meet the requirements of battery cells with smaller thickness.

[0081] like Figure 6 or Figure 8 As shown, the terminal post 20 is disposed on the top cover plate 12 and is used to connect with the tab. The terminal post 20 can be electrically connected to the electrode assembly 200 for outputting or inputting electrical energy of the battery cell. The terminal post 20 includes a positive terminal post and a negative terminal post. The positive terminal post is used to connect to the positive tab, thereby introducing the positive current of the battery cell into the interior of the housing 300 or leading it out to the exterior of the housing 300. The negative terminal post is used to connect to the negative tab, thereby introducing the negative current of the battery cell into the interior of the housing 300 or leading it out to the exterior of the housing 300. The positive and negative terminals of adjacent battery cells can be electrically connected in series, parallel, or mixed manner through electrical connecting pieces.

[0082] It should be noted that the "terminal 20" mentioned in this application can be either a positive terminal or a negative terminal (unless otherwise specified). The "tab 201" mentioned in this application can be either a positive tab 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.

[0083] As one embodiment of pole post 20, such as Figure 8 or Figure 10 As shown, the pole post 20 includes at least two first connecting portions 21 and at least one second connecting portion 22. Each second connecting portion 22 is connected to two adjacent first connecting portions 21, and the at least two first connecting portions 21 are arranged at intervals along a second direction Y. The second connecting portions 22 are located on the side of the top cover plate 12 opposite to the first insulating member 11 for connection with an electrical connector. At least a portion of the first connecting portion 21 passes through a first through hole 121 on the top cover plate 12 to connect with the tab 201. Figure 8 As shown, the first connecting portion 21 has a first electrical connection surface 210, which is connected to the tab 201. The first electrical connection surface 210 is a welding surface for welding with the tab 201, and the solder joint between the tab 201 and the first electrical connection surface 210 can extend from the tab 201 through the first electrical connection surface 210 into the interior of the first connecting portion 21. Figure 12 As shown, the second connecting portion 22 has a second electrical connection surface 220, which is a welding surface for welding with an electrical connector. The solder mark between the electrical connector and the second electrical connection surface 220 can extend from the electrical connector through the second electrical connection surface 220 into the interior of the second connecting portion 22.

[0084] It is understood that in some other embodiments, the first connecting portion 21 of the pole post 20 may also be one. Alternatively, the number of first connecting portions 21 may be two, but not limited to two, and may also be three, four or more, etc. The number of first connecting portions 21 may correspond to the number of electrode assemblies 200 within the housing 300, so that each first connecting portion 21 is respectively connected to a set of tabs 201.

[0085] When the number of electrode assemblies 200 disposed within the housing 300 is N, the number of first connecting portions 21 is also set to N, where N is an integer greater than or equal to 1. The N first connecting portions 21 are spaced apart along the width direction of the top cover plate 12 and connected to the second connecting portions 22. The N first connecting portions 21 pass through the top cover plate 12 and the first insulating member 11, and are correspondingly connected to the tabs 201 of each group of electrode assemblies 200.

[0086] The first connecting part 21 of this application embodiment can be directly laser welded to the tab 201. Therefore, at least part of the first connecting part 21 passes through the first through hole 121 of the top cover plate 12 and extends into the housing 300 to be directly connected to the tab 201. No adapter plate structure is required, which reduces the use of parts, reduces the cost of the battery cell, and at the same time reduces the internal resistance of the battery cell and increases the energy density of the battery cell.

[0087] In some other embodiments, when the number of first connecting portions 21 is at least two, the number of second connecting portions 22 is not limited to one, but can also be two or more. The number of second connecting portions 22 is related to the number of first connecting portions 21. A second connecting portion 22 is provided between two adjacent first connecting portions 21. For example, when the number of first connecting portions 21 is 2, the number of second connecting portions 22 is 1. When the number of first connecting portions 21 is 3, the number of second connecting portions 22 is 2. When the number of first connecting portions 21 is 4, the number of second connecting portions 22 is 3, and so on. The first connecting portions 21 and the second connecting portions 22 are arranged alternately along the width direction of the top cover plate 12. For example, when the number of first connecting portions 21 is 3 and the number of second connecting portions 22 is 2, the pole post 20 includes, along the thickness direction of the top cover plate 12, a first connecting portion 21, a second connecting portion 22, a first connecting portion 21, a second connecting portion 22, and a first connecting portion 21 connected in sequence.

[0088] As one embodiment of the first insulating element 11, such as Figure 6 , Figure 7 and Figure 8 As shown, the first insulating member 11 is disposed on the surface of the top cover plate 12 along the third direction Z. Figure 6 As shown in this embodiment, a first insulating member 11 is disposed on the surface of the top cover plate 12 facing the electrode assembly 200, for insulating the top cover plate 12 and the electrode assembly 200 to reduce the risk of short circuit. Exemplarily, the first insulating member 11 can be a plastic material, such as PP, PE, or PPS. The first insulating member 11 has a second through hole 113, and the first through hole 121 of the top cover plate 12 and the second through hole 113 of the first insulating member 11 are connected to allow the first connecting portion 21 of the electrode post 20 to pass through the first through hole 121 and the second through hole 113, enabling direct welding of the electrode post 20 to the electrode tab 201.

[0089] In some embodiments, in order to fix the top cover 12 and the first insulating member 11, such as Figure 10As shown, a second fixing portion 115 is provided on the surface of the first insulating member 11 facing the top cover plate 12, and the first insulating member 11 is fixed to the top cover plate 12 by the second fixing portion 115. The second fixing portion 115 can be a thermofusion column. The thermofusion column and the top cover plate 12 are connected by ultrasonic thermofusion to fix the first insulating member 11 to the top cover plate 12. In some embodiments, the number of second fixing portions 115 can include multiple portions, and the multiple second fixing portions 115 can be distributed at intervals along the length and width directions of the first insulating member 11. This arrangement can evenly distribute the connection force between the first insulating member 11 and the top cover plate 12, prevent the first insulating member 11 from shifting due to uneven force, and ensure a stable connection between the first insulating member 11 and the top cover plate 12.

[0090] In some embodiments, on a dummy plane perpendicular to the third direction Z, the orthographic projection of the second fixing part 115 does not overlap with the orthographic projection of the first fixing part 112 and the orthographic projection of the support member 111. Therefore, when connecting the first insulating member 11 and the top cover plate 12, a fixture that facilitates ultrasonic heat fusion can press against the surface of the first insulating member 11, simultaneously heat-fusion connecting multiple second fixing parts 115, thus improving connection efficiency.

[0091] like Figure 9 As shown, in some embodiments, at least two second through holes 113 are provided at intervals along the second direction Y, so that each first connecting part 21 can pass through a second through hole 113 and thus connect to the electrode tab 201. It can be understood that the number of second through holes 113 can be the same as the number of first connecting parts 21. Each first connecting part 21 is correspondingly passed through a second through hole 113.

[0092] like Figure 11As shown, in some embodiments, the width of the second through hole 113 along the second direction Y is w3, satisfying: 3mm ≤ w3 ≤ 15mm. For example, w3 can be located within the ranges of: 4mm ≤ w3 ≤ 15mm, 4mm ≤ w3 ≤ 12mm, 4.5mm ≤ w3 ≤ 10mm, 5mm ≤ w3 ≤ 8mm, etc. Specifically, w3 = 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm, etc., including but not limited to the values ​​listed above, and other values ​​between any two of the above still apply. In this way, the width of the second through hole 113 allows the first connecting portion 21 of the pole post 20 to pass through, while not affecting the setting width of the support member 111 in the width direction of the first insulating member 11. When the width w3 of the second through hole 113 is less than 4mm, the width of the second through hole 113 will be too small, affecting the width of the first connecting portion 21, and thus affecting the flow area of ​​the pole post 20. When the width of the second through hole 113 is greater than 15mm, the reserved width between the hole wall of the second through hole 113 and the edge side of the first insulating member 11 will be small, resulting in a smaller width of the support member 111. If the support member 111 is to fully support the welding fixture 400, the wall thickness of the welding fixture 400 needs to be very small so as not to press the first connecting part 21 of the pole post 20. This will cause the welding fixture 400 to be fully pressed on the support member 111. After multiple pressing, the welding fixture 400 will be easily deformed and its lifespan will be shortened.

[0093] like Figure 11 As shown, in some embodiments, along the second direction Y, the width of the second through hole 113 is w3, and the maximum width of the top cover plate 12 is w4, satisfying: 5% ≤ w3 / w4 ≤ 30%. For example, w3 / w4 can be within the ranges of: 5% ≤ w3 / w4 ≤ 25%, 5% ≤ w3 / w4 ≤ 22%, 6% ≤ w3 / w4 ≤ 20%, 10% ≤ w3 / w4 ≤ 20%, 5% ≤ w3 / w4 ≤ 10%, etc. Specifically, w3 / w4 = 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 15%, 17%, 19%, 21%, 23%, 25%, 26%, 27%, 29%, or 30%, etc., including but not limited to the values ​​listed above, and other values ​​between any two of the above still apply. This configuration allows the first connecting portion 21 of the pole post 20 to pass through the width of the second through hole 113 without affecting the width of the support member 111 in the width direction of the first insulating member 11.

[0094] As one embodiment of the support member 111, the support member 111 is at least partially disposed around the periphery of the electrode post 20 to support part of the electrode tab during electrode tab welding. Specifically, the support member 111 can be disposed entirely around the electrode post 20, or only along one side of the electrode post 20, or along a portion of the edge of the electrode post 20. It can be continuous or have partial gaps. It should be noted that when the support member 111 is disposed only along one side or a portion of the edge of the electrode post 20, the design of the electrode tab and the battery cell must also be adapted accordingly to ensure that the support member 111 can provide good support for the electrode tab during electrode tab welding to the electrode post, avoiding problems such as electrode tab tearing.

[0095] More specifically, such as Figure 7 , Figure 8 or Figure 9 As shown, the support member 111 is disposed on the side surface of the first insulating member 11 facing away from the top cover plate 12, and the support member 111 is used to support the electrode tab. By using the support member 111 to support the electrode tab, when the electrode tab 201 and the electrode post 20 are connected, the support member 111 supports the electrode tab 201 and the welding fixture 400 located above the electrode tab, so that the pressure distribution of the welding fixture 400 is uniform, the positioning accuracy of the welding fixture 400 is improved, and laser leakage is avoided during welding, thereby improving the welding effect. At the same time, it avoids the electrode tab being deformed by pressure, thereby improving the conductivity and service life of the battery.

[0096] In some embodiments, the support member 111 and the first insulating member 11 are integrally formed, thereby facilitating the processing of both the first insulating member 111 and the support member 111. For example... Figure 7 , Figure 8 or Figure 9 As shown, the support member 111 protrudes from the surface of the first insulating member 11. It can be understood that the support member 111 can protrude from the surface of the first insulating member 11 toward the electrode assembly 200 toward the electrode assembly 200, such that the surface of the support member 111 is higher than the surface of the first insulating member 11. In this way, the support member 111 can be supported below the electrode tab 201, effectively supporting the electrode tab and the welding fixture 400 located above the electrode tab.

[0097] In some embodiments, such as Figure 9As shown, when the electrode assembly 200's tab 201 is assembled with the top cover assembly 100, the electrode assembly 200 lies flat, and the tab 201 extends from one side edge of the first insulating member 11 to above the first connecting portion 21 of the electrode post 20. Therefore, the support member 111 may include a first portion 1111, which is disposed along the second direction Y between the second through hole 113 and one side edge of the first insulating member 11. It can be understood that the first portion 1111 may extend from one side edge of the first insulating member 11 to the wall of the second through hole 113. In some embodiments, along the second direction Y, the first portion 1111 is aligned with the edge of the first insulating member 11, away from the edge of the second through hole 113. Thus, when the tab 201 of the electrode assembly 200 is welded to the first connecting part 21, the first part 1111 can be supported below the tab 201 near the main body of the electrode assembly 200, thereby providing support for the tab 201 and the welding fixture 400 located above the tab 201.

[0098] In some other embodiments, such as Figure 9 As shown, to further improve the support for the tab 201 and the welding fixture 400 located above the tab 201, the support member 111 also includes a second part 1112. The second part 1112 is disposed between the second through hole 113 and the other edge of the first insulating member 11, and is disposed opposite to the first part 1111. It can be understood that the second part 1112 is disposed on the other side of the second through hole 113 opposite to the first part 1111. Along the third direction Z, the second through hole 113 penetrates the support member 111. Thus, when the tab 201 of the electrode assembly 200 is welded to the first connecting part 21, the first part 1111 and the second part 1112 can be supported below the tabs 201 located on both sides of the first connecting part 21 along the second direction Y, making the positioning of the welding fixture 400 more accurate and improving the welding effect.

[0099] In some embodiments, such as Figure 9 As shown, along the second direction Y, two second portions 1112 located between two adjacent second through holes 113 are spaced apart; that is, the two second portions 1112 located between two adjacent second through holes 113 are not connected together. At this time, the length of the second portion 1112 corresponding to each second through hole 113 along the second direction Y only needs to be sufficient to effectively support the tab 201 below. Thus, for the connection between each first connecting portion 21 and each tab 201, the welding fixture 400 can be individually pressed onto the top of the tab 201, and the first portion 1111 and the second portion 1112 can provide support for the welding fixture 400, ensuring the welding effect.

[0100] In some other embodiments, two second portions 1112 located between two adjacent second through holes 113 are connected as a single unit. It is understood that, in this embodiment, the second portion 1112 extends from the wall of one second through hole 113 to the wall of the other second through hole 113. This can provide additional support for the tab 201 and the welding fixture 400 located above the tab 201.

[0101] In some embodiments, such as Figure 9 As shown, the support member 111 further includes a third part 1113 and a fourth part 1114. The third part 1113 is disposed on one side of the second through hole 113 along the first direction X; the fourth part 1114 is disposed on the other side of the second through hole 113 along the first direction X. In this way, the support member 111 can provide support for the electrode tab 201 and the welding fixture 400 located above the electrode tab 201 on the four sides of the second through hole 113.

[0102] In some embodiments, the support member 111 is disposed circumferentially around the second through hole 113. For example, the support member 111 may be as follows: Figure 9 In the illustrated embodiment, the support 111 extends circumferentially around the second through hole 113. This arrangement allows the support 111 to provide stable support for the peripheral tabs 201 of the soldered electrode, avoiding the problem of localized deformation of the tabs 201 under pressure.

[0103] In some embodiments, such as Figure 11As shown, along the second direction Y, the minimum distance between the edge of the support member 111 and the wall of the second through hole 113 is w1, satisfying: 1mm≤w1≤10mm. For example, w1 can be located within multiple intervals such as 1mm≤w1≤9mm, 1mm≤w1≤8mm, 2mm≤w1≤8mm, 3mm≤w1≤7mm, 4mm≤w1≤7mm, 5mm≤w1≤6mm, etc. Specifically, w1 = 1mm, 1.5mm, 1.7mm, 2mm, 2.5mm, 2.6mm, 3mm, 3.3mm, 3.8mm, 4mm, 4.6mm, 5mm, 5.5mm, 6mm, 6.2mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, or 10mm, including but not limited to the values ​​listed above. Other values ​​between any two of the above are still applicable. This design allows the support member 111 to meet the wall thickness requirements of the welding fixture 400, making the welding fixture 400 less prone to deformation. When the minimum distance w1 between the edge of the support member 111 and the wall of the second through hole 113 is less than 1mm, the wall thickness of the welding fixture 400 needs to be very small to ensure that the support member 111 fully supports the welding fixture 400, thus avoiding pressing the first connecting part 21 of the pole post 20. Repeated pressing would cause the welding fixture 400 to easily deform and shorten its lifespan. When the minimum distance w1 between the edge of the support member 111 and the wall of the second through hole 113 is greater than 10mm, the first insulating member 11 will have a wider thickened area, making it prone to shrinkage and affecting the product appearance.

[0104] In some embodiments, such as Figure 11As shown, along the first direction X, the minimum distance between the edge of the support member 111 and the wall of the second through hole 113 is w2, which satisfies: 1mm≤w2≤10mm. For example, w2 can be located in multiple intervals such as 1mm≤w2≤9mm, 1mm≤w2≤8mm, 2mm≤w2≤8mm, 3mm≤w2≤7mm, 4mm≤w2≤7mm, and 5mm≤w2≤6mm. Specifically, w2 = 1mm, 1.5mm, 1.7mm, 2mm, 2.5mm, 2.6mm, 3mm, 3.3mm, 3.8mm, 4mm, 4.6mm, 5mm, 5.5mm, 6mm, 6.2mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, or 10mm, including but not limited to the values ​​listed above. Other values ​​between any two of the above are still applicable. This configuration allows the support member 111 to meet the wall thickness requirements of the welding fixture 400, making the welding fixture 400 less prone to deformation. When the minimum distance w2 between the edge of the support member 111 and the wall of the second through hole 113 is less than 1mm, the wall thickness of the welding fixture 400 needs to be very small to ensure that the support member 111 fully supports the welding fixture 400, thus avoiding pressing the first connecting part 21 of the pole post 20. Repeated pressing would cause the welding fixture 400 to easily deform and shorten its lifespan. When the minimum distance w2 between the edge of the support member 111 and the wall of the second through hole 113 is greater than 10mm, the first insulating member 11 will have a wider thickened area, making it prone to shrinkage and affecting the product appearance. It should be noted that w1 and w2 can be equal or unequal.

[0105] In some embodiments, such as Figure 8 As shown, along the third direction Z, the support member 111 has a support surface 1110, and the first connecting part 21 has a first electrical connection surface 210. The first electrical connection surface 210 is connected to the electrode tab, and the support surface 1110 and the first electrical connection surface 210 are on the same plane. This ensures that when the electrode assembly 200 is laid flat for welding, there is no gap between the electrode tab 201 and the support member 111 of the first insulating member 11, which serves to support the electrode tab 201 or the welding fixture 400 and avoids the problem of local deformation of the electrode tab 201.

[0106] In some embodiments, such as Figure 12As shown, along the third direction Z, the first connecting portion 21 has a first electrical connection surface 210 and a first stepped surface 23. The first electrical connection surface 210 protrudes from the first stepped surface 23, and a side wall surface 211 connects the first electrical connection surface 210 and the first stepped surface 23. That is, the first electrical connection surface 210 is closer to the tab 201 of the electrode assembly 200 than the first stepped surface 23, so that the first electrical connection surface 210 can be connected to the tab 201, avoiding interference and damage to the tab 201 from other components. The support member 111 extends to the first stepped surface 23 and abuts against the side wall surface 211. This allows the support member 111 to effectively support the tab 201 below, avoiding the problem of local deformation of the tab 201 due to pressure from the welding fixture 400.

[0107] In some embodiments, the tab 201 is welded to the first connecting portion 21 to form a welded portion. Along the second direction Y, the end of the tab 201 is located between the welded portion and the edge of the support member 111, or along the second direction Y, the end of the tab 201 extends beyond the edge of the support member 111. It is understood that the tab 201 includes a connecting end connected to the electrode plate and a free end away from the electrode plate. The aforementioned end of the tab 201 refers to the free end of the tab 201. The free end of the tab 201 can be located between the welded portion and the edge of the support member 111, or it can be set beyond the edge of the support member 111, as long as it can be ensured that the free end of the tab 201 can be pressed down by the welding fixture 400 to ensure the welding effect of the tab 201 and the first connecting portion 21 of the pole post 20.

[0108] In some embodiments, such as Figure 6 and Figure 15 As shown, the electrode assembly 200 is covered with a third insulating element 500, which can be an insulating film. The third insulating element 500 is used to cover the outer surface of the electrode assembly 200 to reduce the risk of short circuit. Figure 13 , Figure 14 and Figure 15 As shown, the third insulating member 500 includes a first covering portion 501 and a second covering portion 503. The first covering portion 501 covers the end face of the electrode assembly 200 facing the top cover assembly 100 to insulate the electrode assembly 200 from the top cover assembly 100. The first covering portion 501 also has a third through hole 502. The third through hole 502 corresponds to the second through hole 113 of the first insulating member 11, allowing the first connecting portion 21 of the electrode post 20 to pass through the third through hole 502 and connect to the electrode tab 201. The second covering portion 503 covers the side surface of the electrode assembly 200 and the bottom end facing away from the top cover assembly 100 to insulate the electrode assembly 200 from the housing 300.

[0109] At least a portion of the first covering portion 501 is disposed between the support member 111 and the tab 201. Therefore, in order to provide a certain reserved space for the first covering portion 501 of the third insulating member 500, in some embodiments, such as... Figure 12 As shown, along the third direction Z, the first electrical connection surface 210 of the first connection portion 21 extends beyond the support surface 1110 of the support member 111. It is understood that the first electrical connection surface 210 and the support surface 1110 are not on the same plane; the first electrical connection surface 210 is closer to the tab 201 relative to the support surface 1110. Along the third direction Z, a gap is formed between the dummy plane containing the first electrical connection surface 210 and the support surface 1110, the gap accommodating at least a portion of the third insulating member 500, i.e., a portion of the first covering portion 501. Thus, when the electrode assembly 200 lies flat and the tab 201 is placed above the first connection portion 21 of the electrode post 20, the support surface 1110 of the support member 111 is supported below the first covering portion 501. The surface of the first covering portion 501 facing the tab 201 is on the same plane as the first electrical connection surface 210 of the first connecting portion 21; this allows the tab 201 to be supported above the first covering portion 501 and the support member 111, thereby providing effective support for the welding fixture 400.

[0110] In some embodiments, such as Figure 12 As shown, along the third direction Z, the distance between the first electrical connection surface 210 and the support surface 1110 is d, which satisfies: 0.05mm≤d≤0.25mm. For example, d can be located within multiple intervals such as 0.05mm≤d≤0.2mm, 0.05mm≤d≤0.18mm, 0.05mm≤d≤0.15mm, 0.08mm≤d≤0.2mm, 0.1mm≤d≤0.2mm, and 0.15mm≤d≤0.18mm. Specifically, d = 0.08mm, 0.09mm, 0.1mm, 0.12mm, 0.13mm, 0.14mm, 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.2mm, 0.21mm, 0.22mm, 0.23mm, 0.24mm, or 0.25mm, including but not limited to the values ​​listed above. Other values ​​between any two of the above still apply. This arrangement ensures that the distance d between the first electrical connection surface 210 and the support surface 1110 is not too large, thus preventing loss of support for the tab 201 and the welding fixture 400. In some embodiments, along the third direction Z, the distance between the first electrical connection surface 210 of the first connection portion 21 and the support surface 1110 of the support member 111 is consistent with the thickness of the first covering portion 501. This allows the first covering portion 501 of the third insulating member 500 to be accommodated within the gap between the support surface 1110 and the first electrical connection surface 210, thereby providing support for the tab 201 located on the first covering portion 501.

[0111] In some embodiments, such as Figure 9 As shown, a first fixing part 112 is also provided on the surface of the first insulating member 11 facing away from the top cover plate 12. Along the third direction Z, the first fixing part 112 has a fixing surface 1121, which is on the same plane as the support surface 1110. The first fixing part 112 is used to fix the first covering part 501 of the third insulating member 500. The first fixing part 112 can be fixedly connected to the third insulating member 500 by heat fusion. By setting the fixing surface 1121 of the first fixing part 112 and the support surface 1110 of the support member 111 to be on the same plane, the flatness of the third insulating member 500 can be ensured.

[0112] like Figure 9 As shown, to further ensure the flatness of the third insulating member 500, four first fixing parts 112 are included, and the four first fixing parts 112 are respectively disposed at the four corners of the first insulating member 11. This allows the third insulating member 500 to be more stably fixed to the surface of the first insulating member 11. In some embodiments, the area of ​​the orthographic projection of the first fixing part 112 on the surface of the first insulating member 11 is smaller than the area of ​​the orthographic projection of the support member 111 on the surface of the first insulating member 11. This is to avoid the first fixing part 112 occupying too much space, thereby affecting the setting of the support member 111.

[0113] like Figure 9 As shown, the support member 111 and the first fixing part 112 are connected as an integral structure by the connecting part 114. Specifically, along the second direction Y, the width of the connecting part 114 is smaller than the width of the first fixing part 112 and smaller than the width of the support member 111. This facilitates the processing of the first insulating member 11. The connecting part 114 can also support the third insulating member 500 below the first covering part 501, ensuring the flatness of the third insulating member 500.

[0114] like Figure 8As shown, in some embodiments, when the pole post 20 includes two pole posts and a negative pole post spaced apart along the first direction X, each pole post 20 includes two first connecting portions 21, the first insulating member 11 includes two second through holes 113 spaced apart along the second direction Y, each first connecting portion 21 is correspondingly inserted into a second through hole 113, the support member 111 includes two sets spaced apart along the first direction X, each set includes two support members 111 spaced apart along the second direction Y, and each support member 111 is corresponding to a second through hole 113, along the first direction X, adjacent sets of support members 111 are connected into an integral structure by connecting portions 114, and along the second direction Y, the width of the connecting portion 114 is smaller than the width of each support member 111, which facilitates the processing of the first insulating member 11, and at the same time, the connecting portion 114 can also be supported below the first covering portion 501 of the third insulating member 500 to ensure the flatness of the third insulating member 500.

[0115] As one embodiment of the second insulating element 13, such as Figure 8 or Figure 12 As shown, the second insulating member 13 is fixedly connected to the pole post 20 and the top cover plate 12. The second insulating member 13 includes a first insulating part 131, a second insulating part 132 and a third insulating part 130 connected to each other. The first insulating part 131 is located on the side of the top cover plate 12 facing the first insulating member 11. The second insulating part 132 is located between the hole wall of the first through hole 121 and the first connecting part 21 of the pole post 20. The third insulating part 130 is located on the side of the top cover plate 12 facing away from the first insulating member 11.

[0116] On a dummy plane perpendicular to the third direction Z, the orthographic projection of the first insulating portion 131 overlaps with the orthographic projection of the top cover plate 12. It is understood that at least a portion of the orthographic projection of the first insulating portion 131 falls on the solid structure of the top cover plate 12, which does not include the first through hole 121. That is, at least a portion of the orthographic projection of the first insulating member 11 on the dummy plane overlaps with the orthographic projection of the top cover plate 12 on the same dummy plane, causing at least a portion of the first insulating portion 131 to bend towards the inner surface of the top cover plate 12 below the wall of the first through hole 121. Here, the inner surface of the top cover plate 12 refers to the surface of the top cover plate 12 facing the electrode assembly 200, and it connects or snaps with the lower surface of the top cover plate 12. This improves the fixation effect on the electrode post 20 through the first insulating portion 131, and insulates the lower surface of the top cover plate 12 from the electrode post 20, while also providing a seal to prevent electrolyte leakage from the first through hole 121.

[0117] In some embodiments, such as Figure 12As shown, the surface of the first insulating member 11 facing the top cover plate 12 is recessed to form a groove 116, and the surface facing away from the top cover plate 12 is correspondingly protruded to form a support member 111. The second through hole 113 penetrates the bottom of the groove 116, and the first insulating part 131 is accommodated in the groove 116 and at least abuts against the bottom of the groove 116. In this way, the first insulating part 131 of the first insulating member 11 can be supported below the support member 111, further providing support for the tab 201 above the support member 111 and the welding fixture 400 located above the tab 201.

[0118] The second insulating portion 132 is disposed between the wall of the first through hole 121 and the first connecting portion 21 of the electrode post 20, so as to connect the first connecting portion 21 and the wall of the first through hole 121 through the second insulating portion 132 and form insulation, and at the same time, it can also play a sealing role to prevent electrolyte from leaking out of the first through hole 121. The second insulating portion 132 can be in a ring shape, with one end of the second insulating portion 132 facing the inside of the housing connected to the first insulating portion 131, and the other end of the second insulating portion 132 facing the outside of the housing connected to the third insulating portion 130.

[0119] The third insulating portion 130 is disposed on the outer side of the top cover plate 12. It is understood that the third insulating portion 130 covers the pole portion located on the outer side of the top cover plate 12, thereby insulating the pole portion located on the outer surface of the top cover plate 12 and the top cover plate 12. Simultaneously, the third insulating portion 130 also serves a sealing function. Along the thickness direction of the top cover plate 12, at least a portion of the orthographic projection of the third insulating portion 130 falls on the top cover plate 12; that is, on a virtual plane perpendicular to the thickness direction of the top cover plate 12, the orthographic projection of the third insulating portion 130 overlaps with the orthographic projection of the top cover plate 12. It is understood that the outer contour edge of the third insulating portion 130 protrudes from the wall of the first through hole 121. The first insulating part 131, the second insulating part 132 and the third insulating part 130 are connected as one unit, so that they can be engaged with the top cover plate 12 to improve the fixing effect of the pole post 20; the first insulating part 131 and the third insulating part 130 can jointly hold the top cover plate 12 from both sides in the thickness direction of the top cover plate 12, thereby further improving the fixing effect of the pole post 20.

[0120] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A top cover assembly, characterized in that, include: Top cover plate (12); A pole post (20) is disposed on the top cover plate (12), and the pole post (20) is used to connect with the pole tab; A first insulating element (11) is disposed on one side surface of the top cover plate (12) along the third direction (Z); A support member (111) is provided on the side surface of the first insulating member (11) opposite to the top cover plate (12), and the support member (111) is at least partially provided around the periphery of the pole post (20).

2. The top cover assembly according to claim 1, characterized in that, The support member (111) and the first insulating member (11) are integrally formed, and the support member (111) protrudes from the surface of the first insulating member (11).

3. The top cover assembly according to claim 2, characterized in that, The pole post (20) includes at least two first connecting parts (21) and at least one second connecting part (22). Each second connecting part (22) is connected to two adjacent first connecting parts (21). At least two first connecting parts (21) are arranged at intervals along a second direction (Y). The second connecting part (22) is located on the side of the top cover plate (12) away from the first insulating member (11) and is used to connect with an electrical connector. The top cover plate (12) is provided with a first through hole (121). The first insulating member (11) is provided with a second through hole (113). At least a portion of the first connecting part (21) passes through the first through hole (121) and the second through hole (113) and is used to connect with the electrode tab. The support member (111) includes a first part (1111) disposed along the second direction (Y) between the second through hole (113) and one side edge of the first insulating member (11); wherein the second direction (Y) intersects with the third direction (Z).

4. The top cover assembly according to claim 3, characterized in that, The support member (111) further includes a second part (1112), which is disposed along the second direction (Y) between the second through hole (113) and the other edge of the first insulating member (11) and is disposed opposite to the first part (1111). Along the third direction (Z), the second through hole (113) penetrates the support member (111).

5. The top cover assembly according to claim 4, characterized in that, Along the second direction (Y), at least two second through holes (113) are provided at intervals, and each first connecting part (21) is correspondingly inserted into one of the second through holes (113). Along the second direction (Y), two second parts (1112) located between two adjacent second through holes (113) are provided at intervals; or, two second parts (1112) located between two adjacent second through holes (113) are connected as one unit.

6. The top cover assembly according to claim 4, characterized in that, The support member (111) further includes a third part (1113), the third part (1113) being disposed on one side of the second through hole (113) along the first direction (X); and / or, The support member (111) further includes a fourth part (1114), which is disposed on the other side of the second through hole (113) along the first direction (X), wherein the first direction (X), the second direction (Y) and the third direction (Z) intersect each other.

7. The top cover assembly according to claim 6, characterized in that, Along the third direction (Z), the support member (111) has a support surface (1110), the first connecting part (21) has a first electrical connection surface (210), the first electrical connection surface (210) is connected to the electrode tab, and the support surface (1110) and the first electrical connection surface (210) are in the same plane.

8. The top cover assembly according to claim 6, characterized in that, Along the third direction (Z), the support member (111) has a support surface (1110), the first connecting part (21) has a first electrical connection surface (210), the first electrical connection surface (210) is connected to the electrode tab, and the first electrical connection surface (210) extends beyond the support surface (1110).

9. The top cover assembly according to claim 8, characterized in that, Along the third direction (Z), a gap is formed between the dummy plane where the first electrical connection surface (210) is located and the support surface (1110), the gap being used to accommodate at least a portion of the third insulating member (500), the third insulating member (500) being used to cover the outer surface of the electrode assembly (200).

10. The top cover assembly according to claim 9, characterized in that, A first fixing part (112) is also provided on the surface of the first insulating member (11) away from the top cover plate (12). Along the third direction (Z), the first fixing part (112) has a fixing surface (1121), and the fixing surface (1121) and the supporting surface (1110) are on the same plane.

11. The top cover assembly according to claim 10, characterized in that, The support member (111) and the first fixing part (112) are connected as an integral structure by a connecting part (114), wherein, along the second direction (Y), the width of the connecting part (114) is smaller than the width of the first fixing part (112) and smaller than the width of the support member (111); and / or, The pole post (20) includes two pole posts (20) spaced apart along a first direction (X), each pole post (20) including two first connecting portions (21). The first insulating member (11) includes two second through holes (113) spaced apart along a second direction (Y), each first connecting portion (21) corresponding to a second through hole (113). The support member (111) includes two sets spaced apart along the first direction (X), each set including two support members (111) spaced apart along the second direction (Y), and each support member (111) corresponding to a second through hole (113). Along the first direction (X), adjacent sets of support members (111) are connected into an integral structure by a connecting portion (114), and along the second direction (Y), the width of the connecting portion (114) is smaller than the width of each support member (111). The first direction (X), the second direction (Y), and the third direction (Z) intersect each other; and / or, The first fixing part (112) includes four parts, and the four first fixing parts (112) are respectively disposed at the four corners of the first insulating member (11); and / or, The area of ​​the first fixing part (112) projected onto the surface of the first insulating member (11) is smaller than the area of ​​the support member (111) projected onto the surface of the first insulating member (11).

12. The top cover assembly according to claim 10, characterized in that, The first insulating member (11) has a second fixing part (115) on the surface facing the top cover plate (12). The first insulating member (11) is fixed to the top cover plate (12) by the second fixing part (115). On a virtual plane perpendicular to the third direction (Z), the orthographic projection of the second fixing part (115) does not overlap with the orthographic projection of the first fixing part (112) and the orthographic projection of the support member (111).

13. The top cover assembly according to claim 8, characterized in that, Along the third direction (Z), the distance between the first electrical connection surface (210) and the support surface (1110) is d, which satisfies: 0.05mm≤d≤0.25mm.

14. The top cover assembly according to any one of claims 3 to 13, characterized in that, The support member (111) is arranged circumferentially around the second through hole (113).

15. The top cover assembly according to claim 14, characterized in that, Along the second direction (Y), the edge of the first part (1111) opposite to the second through hole (113) is aligned with the edge of the first insulating member (11).

16. The top cover assembly according to any one of claims 3 to 13, characterized in that, Along the third direction (Z), the first connecting portion (21) has a first electrical connection surface (210) and a first stepped surface (23), the first electrical connection surface (210) protrudes from the first stepped surface (23), a side wall surface (211) is connected between the first electrical connection surface (210) and the first stepped surface (23), and the support member (111) extends to the first stepped surface (23) and abuts against the side wall surface (211).

17. The top cover assembly according to any one of claims 3 to 13, characterized in that, Also includes: The second insulating member (13) is fixedly connected to the pole post (20) and the top cover plate (12). The second insulating member (13) includes a first insulating part (131), a second insulating part (132) and a third insulating part (130) connected to each other. The first insulating part (131) is located on the side of the top cover plate (12) facing the first insulating member (11). The second insulating part (132) is located between the hole wall of the first through hole (121) and the first connecting part (21) of the pole post (20). The third insulating part (130) is located on the side of the top cover plate (12) facing away from the first insulating member (11). On a virtual plane perpendicular to the third direction (Z), the orthographic projection of the first insulating part (131) overlaps with the orthographic projection of the top cover plate (12). The first insulating member (11) has a recessed groove (116) on one side of its surface facing the top cover plate (12), and a corresponding protrusion on one side of its surface away from the top cover plate (12) to form the support member (111). The second through hole (113) penetrates the bottom of the groove (116). The first insulating part (131) is accommodated in the groove (116) and at least abuts against the bottom of the groove (116).

18. The top cover assembly according to any one of claims 3 to 13, characterized in that, Along the second direction (Y), the minimum distance between the edge of the support (111) and the wall of the second through hole (113) is w1, satisfying: 1mm ≤ w1 ≤ 10mm; and / or, Along the first direction (X), the minimum distance between the edge of the support (111) and the wall of the second through hole (113) is w2, satisfying: 1mm ≤ w2 ≤ 10mm, wherein the first direction (X), the second direction (Y), and the third direction (Z) intersect each other; and / or, Along the second direction (Y), the width of the second through hole (113) is w3, and the maximum width of the top cover plate (12) is w4, satisfying: 5% ≤ w3 / w4 ≤ 30%; and / or, Along the second direction (Y), the width of the second through hole (113) is w3, satisfying: 3mm ≤ w3 ≤ 15mm; and / or, Along the second direction (Y), the maximum width of the top cover piece (12) is w4, and along the first direction (X), the maximum length of the top cover piece (12) is w5, satisfying: 7% ≤ w4 / w5 ≤ 35%.

19. A single battery cell, characterized in that, include: The top cover assembly (100) according to any one of claims 1 to 18; Casing (300); An electrode assembly (200) is housed within the housing (300). The electrode assembly (200) extends tabs (201), some of which are connected to the pole post (20) and some of which are supported by the support member (111).

20. The battery cell according to claim 19, characterized in that, Also includes: The third insulating member (500) includes a first covering portion (501), which covers the end face of the electrode assembly (200) facing the top cover assembly (100), and the first covering portion (501) is provided with a third through hole (502), and a first connecting portion (21) passes through the third through hole (502) and is connected to the tab (201); at least a portion of the first covering portion (501) is disposed between the support member (111) and the tab (201).

21. The battery cell according to claim 20, characterized in that, The surface of the first covering portion (501) facing the tab (201) is on the same plane as the first electrical connection surface (210) of the first connecting portion (21); and / or, Along the third direction (Z), the distance between the first electrical connection surface (210) of the first connecting part (21) and the support surface (1110) of the support member (111) is consistent with the thickness of the first covering part (501).

22. The battery cell according to claim 20, characterized in that, The electrode tab (201) is welded to the first connecting portion (21) to form a welded portion. Along the second direction (Y), the end of the electrode tab (201) is located between the welded portion and the edge of the support member (111); and / or, Along the second direction (Y), the end of the tab (201) extends beyond the edge of the support (111), wherein the second direction (Y) intersects with the third direction (Z).

23. A battery, characterized in that, Includes the battery cell as described in any one of claims 19 to 22.

24. An electrical appliance, characterized in that, Includes the battery cell as described in any one of claims 19 to 22 or the battery as described in claim 23.

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