Battery cells and batteries

Abstract

This utility model provides a battery cell, comprising: a casing having a cavity and an opening; an electrode assembly disposed in the cavity, the end of the electrode assembly facing the opening including a tab; a cover assembly including: a cover body covering the opening, the cover body having a first through hole; a terminal post including a terminal post body extending along a first direction and an end plate extending along a first plane, the end plate being at least partially connected to the outer wall of the terminal post body circumferentially, the end plate being disposed on the side of the cover body opposite to the electrode assembly, the end plate including a first surface opposite to the electrode assembly, the tab passing through the first through hole and connected to the first surface, the first direction being the thickness direction of the cover body, the first plane being perpendicular to the first direction; and a top cover connecting the terminal post and the cover body to seal the first through hole, the tab being located between the top cover and the end plate in the first direction. The purpose of this utility model is to provide a battery cell and a battery to at least improve the energy density of the battery cell.

Description

Technical Field

[0001] This utility model relates to a battery cell and a battery. Background Technology

[0002] With the development of lithium battery technology, the demand for higher battery energy density is increasing. Currently, square aluminum-cased batteries mostly use connecting tabs as a bridge between the electrode assembly and the cover plate. The connecting tabs are used to connect the electrode assembly and the cover plate together. The connecting tabs themselves have a certain thickness, which will encroach on the size of the electrode assembly inside the battery and limit the improvement of battery energy density. Another process route is to eliminate the connecting tabs and use ultrasonic welding to weld the originally loose tabs of the electrode assembly into a whole. Then, laser welding is used to weld the tabs to the cover plate. Both processes have room for improvement in battery energy density. Utility Model Content

[0003] In view of the problems existing in the related technologies, the purpose of this utility model is to provide a battery cell and a battery to at least improve the energy density of the battery cell.

[0004] To achieve the above objectives, this utility model provides a battery cell, comprising: a shell having a cavity and an opening; an electrode assembly disposed in the cavity, the end of the electrode assembly facing the opening including a tab; a cover assembly including: a cover body covering the opening, the cover body having a first through hole; a terminal post including a terminal post body extending along a first direction and an end plate extending along a first plane, the end plate being at least partially connected to the outer wall of the terminal post body circumferentially, the end plate being disposed on the side of the cover body opposite to the electrode assembly, the end plate including a first surface opposite to the electrode assembly, the tab passing through the first through hole and connected to the first surface, the first direction being the thickness direction of the cover body, the first plane being perpendicular to the first direction; and a top cover connecting the terminal post and the cover body to seal the first through hole, the tab being located between the top cover and the end plate in the first direction.

[0005] The beneficial technical effects of this utility model are as follows: In the embodiment of this application, a first through hole is opened on the cover plate body, and the electrode tab extends out from the first through hole and connects to the back of the end plate. Compared with the prior art, it saves the space occupied by the connecting piece and the space required for folding the electrode tab, improves the energy density of the battery cell, and the outward folding of the electrode tab can reduce the probability of the electrode tab being inserted into the back.

[0006] In some embodiments, along a second direction, the edge of the end plate extends beyond or is aligned with the edge of the pole body, the second direction being the length direction of the cover plate body; and / or along a third direction, the end plate extends to the edge of the first through hole, the third direction being the width direction of the cover plate body.

[0007] In some embodiments, along a first direction, the electrode post is located on the side of the cover plate body away from the electrode assembly, the end plate is connected to the end of the electrode post body facing the electrode assembly, and a lower insulating member is provided between the end plate and the cover plate body.

[0008] In some embodiments, the edge of the cover is welded to the cover body, and the distance between the edge of the cover and the first through hole is greater than or equal to 0.1 mm.

[0009] In some embodiments, an insulating layer is provided between the electrode tab and the cover plate body, and between the electrode tab and the top cover.

[0010] In some embodiments, the cover plate body is provided with a second through hole, the pole body passes through the second through hole, the lower insulating member disposed between the end plate and the cover plate body extends to the second through hole, and the portion of the lower insulating member located in the second through hole is located between the pole body and the cover plate body.

[0011] In some embodiments, the cover assembly further includes: an upper plastic, the electrode post further includes an outer fixing member connected to one end of the electrode post body opposite to the electrode assembly, the upper plastic being sandwiched between the outer fixing member and the upper cover; and a sealing ring disposed between the upper cover and the electrode post body.

[0012] In some embodiments, the top cover includes a first top cover and a second top cover, the electrode tab includes a first electrode tab and a second electrode tab, the electrode post includes a first electrode post and a second electrode post respectively connected to the first electrode tab and the second electrode tab, the first top cover corresponds to the first electrode tab and the first electrode post, and the second top cover corresponds to the second electrode tab and the second electrode post.

[0013] In some embodiments, the electrode assembly includes a multilayer first electrode group and a multilayer second electrode group, and the end plate includes a first end plate and a second end plate corresponding to the first electrode post and the second electrode post, respectively. The first electrode group and the second electrode group are welded to the first end plate and the second end plate, respectively. The thickness of the first end plate and the second end plate is between 1 mm and 2 mm.

[0014] Embodiments of this application also provide a battery, including the aforementioned battery cell. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly described 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. It is worth noting that, according to industry standard practice, the components are not drawn to scale and are only used for illustrative purposes. In fact, for clarity of discussion, the dimensions of the components can be arbitrarily increased or decreased.

[0016] Figure 1 A perspective view of a battery cell according to an embodiment of this application is shown.

[0017] Figure 2 The first embodiment of this application is shown. Figure 1 The cross-sectional view taken from line AA.

[0018] Figure 3 It shows Figure 2 A magnified view of region B in the middle.

[0019] Figure 4 A top view of the cover plate body according to the first embodiment of this application is shown.

[0020] Figure 5 A top view of a cover plate assembly according to the first and second embodiments of this application is shown.

[0021] Figure 6 The second embodiment of this application is shown. Figure 1 The cross-sectional view taken from line AA.

[0022] Figure 7 It shows Figure 6 A magnified view of region C in the middle.

[0023] Figure 8 A top view of the cover plate body according to a second embodiment of this application is shown.

[0024] Figure 9 The pole body and end plate of the pole according to the first and second embodiments of this application are shown.

[0025] Figure 10 A schematic diagram is shown when the electrical device in an embodiment of this application is a vehicle. Detailed Implementation

[0026] To better understand the spirit of the embodiments of this application, the following description is based on some preferred embodiments of this application.

[0027] Embodiments of this application will be described in detail below. Throughout this specification, identical or similar components and components having identical or similar functions are indicated by similar reference numerals. The embodiments described herein with reference to the accompanying drawings are illustrative and diagrammatic in nature and are intended to provide a basic understanding of this application. The embodiments of this application should not be construed as limiting this application.

[0028] As used herein, the terms “approximately,” “generally,” “substantially,” and “about” are used to describe and indicate minor variations. When used in conjunction with an event or situation, these terms may refer to examples in which the event or situation occurred precisely or in examples in which the event or situation occurred very approximately.

[0029] In this specification, unless otherwise specified or limited, relative terms such as “central,” “longitudinal,” “lateral,” “front,” “rear,” “right,” “left,” “inner,” “outer,” “lower,” “higher,” “horizontal,” “vertical,” “above,” “below,” “above,” “below,” “top,” “bottom,” and their derivatives (e.g., “horizontally,” “downward,” “upward,” etc.) should be interpreted as referring to the directions described in the discussion or depicted in the accompanying drawings. These relative terms are used for descriptive convenience only and do not require that this application be constructed or operated in a particular orientation.

[0030] For ease of description, "first," "second," "third," etc., can be used in this article to distinguish different components of a figure or a series of figures. "First," "second," "third," etc., are not intended to describe the corresponding components.

[0031] As described in the background art, one existing battery manufacturing process uses connecting tabs as intermediaries connecting the electrode assembly to the cover and casing. These connecting tabs encroach on the size of the internal electrode assembly, limiting the improvement of the battery's energy density. If we calculate based on a casing height of 100mm, and considering that the commonly used connecting tabs are 1mm thick, the battery's energy density will decrease by 1%. On the other hand, regardless of whether connecting tabs are used or eliminated, the height of the empty foil area of ​​the electrode assembly's tabs is generally greater than 25mm due to the constraints of the electrode assembly's thickness direction. This results in significant losses in electrode assembly cost, weight, and energy density. Existing batteries require space for the electrode assembly's tabs, at least 2mm-3mm in height, to prevent tab insertion. This tab space encroaches on the height of the electrode assembly itself. To accommodate this tab space, a plastic component is typically built into the battery to support the electrode assembly. This plastic component is generally >5mm high, further encroaching on the battery's internal space.

[0032] Figure 1 A perspective view of a battery cell 100 according to an embodiment of this application is shown. Figure 2 The first embodiment of this application is shown. Figure 1 The cross-sectional view taken from line AA. Figure 3 It shows Figure 2 A magnified view of region B in the middle. Figure 4A top view of the cover body 42 according to the first embodiment of this application is shown. Figure 5 A top view of a cover assembly 40 according to the first and second embodiments of this application is shown, wherein the first through hole 44, which is covered by the top cover 46, is shown in dashed lines.

[0033] Figure 6 The second embodiment of this application is shown. Figure 1 The cross-sectional view taken from line AA. Figure 7 It shows Figure 6 A magnified view of region C in the middle. Figure 8 A top view of the cover body 42 according to a second embodiment of this application is shown. Figure 9 The pole body 52 and end plate 54 of the pole 50 according to the first and second embodiments of this application are shown.

[0034] The top cover 46 includes a first top cover and a second top cover; the electrode tab 30 includes a first electrode tab and a second electrode tab with opposite polarities; the electrode post 50 includes a first electrode post and a second electrode post respectively connecting the first electrode tab and the second electrode tab; the first top cover corresponds to the first electrode tab and the first electrode post; and the second top cover corresponds to the second electrode tab and the second electrode post. This application uses a cross-section passing through the first electrode post as an example for illustration; it is understood that the configuration on one side of the second electrode post is the same as or similar to that of the first electrode post. In some embodiments, the positive electrode tab is aluminum foil with a thickness of 10-15 μm / layer, and the negative electrode tab is copper foil with a thickness of 4-8 μm / layer.

[0035] Figure 1 and Figure 2 Cross-sectional views of a battery cell 100 according to an embodiment of this application are shown, wherein the views are taken along a plane parallel to the thickness direction T and the height direction H of the battery cell 100. Figure 1 The cross-section shown passes through pole 50. Figure 2 The cross-section shown passes through the second pole 52. In some embodiments, pole 50 is the positive pole and the second pole 52 is the negative pole. Figure 3 A simplified perspective view of a battery cell 100 according to an embodiment of this application is shown.

[0036] An embodiment of this application provides a battery cell 100, including: a housing 10 having a cavity 12 and an opening 14; an electrode assembly 20 disposed in the cavity 12, the end of the electrode assembly 20 facing the opening 14 including a tab 30; a cover plate assembly 40 including: a cover plate body 42 covering the opening 14, the cover plate body 42 having a first through hole 44; and a terminal post 50 including a terminal post body 52 extending along a first direction D1 and an end plate 54 extending along a first plane, the end plate 54 being connected to the outer wall of the terminal post body 52. The end plate 54 is disposed on the side of the cover plate body 42 opposite to the electrode assembly 20, and includes a first surface 55 opposite to the electrode assembly 20. The tab 30 passes through a first through hole 44 and is connected to the first surface 55. The first direction D1 is the thickness direction of the cover plate body 42, and the first plane is perpendicular to the first direction D1. The upper cover 46 connects the electrode post 50 and the cover plate body 42 to seal the first through hole 44. The tab 30 is located between the upper cover 46 and the end plate 54 in the first direction D1. In the embodiments of this application, the first through hole 44 is opened on the cover plate body 42, and the tab 30 extends from the first through hole 44 and connects to the back side of the end plate 54 (opposite to the first surface 55 of the electrode assembly 20). Compared with the prior art, this saves the space occupied by the connecting piece and the space required for folding the tab, improves the energy density of the battery cell 100, and the outward folding of the tab 30 (connected to the back side of the end plate 54) can reduce the probability of the tab 30 being inserted.

[0037] exist Figure 9 In the illustrated embodiment, along the second direction D2 (the length direction of the cover plate body 42), the edge of the end plate 54 is aligned with the edge of the pole body 52. ​​In other embodiments, the dimension of the end plate 54 along the second direction D2 can be larger, that is, the edge of the end plate 54 can extend beyond the pole body 52, or the length of the connection portion of the end plate 54 and the tab 30 along the second direction D2 is greater than the length of the connection portion of the end plate 54 and the pole body 52 along the second direction D2. Specifically, it can be set according to the length of the tab 30 along the second direction D2. See also Figure 3 or Figure 7 Along the third direction D3 (the width direction of the cover body 42), the end plate 54 extends to the edge of the first through hole 44. The end plate 54 may be aligned with the edge of the first through hole 44, or the end plate 54 may extend further to cover at least a portion of the first through hole 44. Compared to embodiments where the end plate 54 does not extend to the edge of the first through hole 44, the tab 30 can be connected to the first surface 55 of the end plate 54 immediately after extending from the first through hole 44, instead of having to cross the cover body 42 to reach the end plate 54, thus saving the length of the tab 30 and reducing costs.

[0038] See Figure 3In the first embodiment, the pole post 50 is located on the side of the cover plate body 42 away from the electrode assembly 20, and the end plate 54 is connected to the end of the pole post body 52 facing the electrode assembly 20. A lower insulating member 74 (e.g., lower plastic) is provided between the end plate 54 and the cover plate body 42. The lower insulating member 74 provides electrical insulation between the pole post 50 and the cover plate body 42.

[0039] See Figure 7 In the second embodiment, the cover plate body 42 is provided with a second through hole 45, the pole post body 52 passes through the second through hole 45, and the lower insulating member 74 disposed between the end plate 54 and the cover plate body 42 extends to the second through hole 45, with the portion of the lower insulating member 74 located in the second through hole 45 positioned between the pole post body 52 and the cover plate body 42. See also Figure 4 and Figure 8 In the second embodiment, a second through hole 45 for assisting in the positioning of the pole post 50 is additionally provided on the cover plate body 42.

[0040] In the first and second embodiments, the edge of the upper cover 46 is welded to the cover plate body 42, and the distance between the edge of the upper cover 46 and the first through hole 44 is greater than or equal to 0.1 mm, so as to ensure that the weld pool of the upper cover 46 and the cover plate body 42 is located outside the second through hole 45, thereby ensuring the welding strength.

[0041] In the first and second embodiments, an insulating layer is provided between the tab 30 and the cover plate body 42, and between the tab 30 and the upper cover 46, to insulate the tab 30 from the cover plate body 42 and the upper cover 46. The insulating layer may be insulating tape attached to the surface of the cover plate body 42 and the upper cover 46 facing the tab 30.

[0042] The electrode assembly 20 includes multi-layered first tabs converged into a first tab group and multi-layered second tabs converged into a second tab group. The end plate includes a first end plate and a second end plate corresponding to the first and second pole posts, respectively. The first tab group and the second tab group are welded to the first end plate and the second end plate, respectively [the connection can be achieved through laser welding (using lasers including single-mode, single-mode ring, multi-mode ring, and green lasers), ultrasonic welding, brazing, molecular thermofusion welding, etc.]. The thickness of the first end plate and the second end plate ranges from 1 mm to 2 mm. In some embodiments, the multi-layered tabs 30 are converged into a tab group and pre-welded into a single unit at the welding portion 9. The welding portion 9 is welded to the end plate, and the welding area between the two does not exceed the welding portion 9. The connection area between the tabs 30 and the end plate 54 is smaller than the area of ​​the welding portion 9 of the tab group. The end plate 54 can be made of pure aluminum, pure copper, stainless steel, etc. To ensure compatibility with welding methods such as laser welding when welding the end plate 54 and the tab 30, the thickness of the end plate 54 needs to be between 1mm and 2mm. If the end plate 54 is too thin, it is easy for the laser weld to penetrate, and it can easily affect the mechanical strength of the battery cell 100. If the end plate 54 is too thick, it will encroach on the height of the internal electrode assembly 20 of the battery cell 100, thus reducing the energy density of the battery cell 100. In some embodiments, insulating tape that provides insulation between the tab 30 and the cover body 42 and the top cover 46 can also be applied to the inner and outer surfaces of the first tab group and the second tab group.

[0043] See Figure 3 and Figure 7 The cover assembly 40 also includes: an upper plastic 70; the electrode post 50 further includes an outer fixing member 56, which is connected to the end of the electrode post body 52 opposite to the electrode assembly 20; the upper plastic 70 is sandwiched between the outer fixing member 56 and the upper cover 46; and a sealing ring 72, which is disposed between the upper cover 46 and the electrode post body 52. ​​The outer fixing member 56 can be a riveted part, a flange, or it can be welded to the electrode post body 52. ​​That is, the inner edge of the upper cover 46 is fixed to the electrode post 50, and the sealing ring 72 achieves a seal between them to prevent leakage. The outer edge of the upper cover 46 is welded to the cover body 42, eliminating the need for other components and allowing for simple and convenient connection and sealing.

[0044] In the actual assembly process, multiple layers of first tabs and second tabs (e.g., 20-100 layers) are respectively bundled and gathered into first tab groups (all first tabs are pre-formed with welding parts 9, which can be pre-pressed into a whole by ultrasonic welding, torque welding, molecular thermofusion welding, etc.) and second tab groups, and then passed out from the first through hole 44 (pre-bundled into first tab groups and second tab groups for easier extension from the first through hole 44), and welded to the first surface 55 of the end plate 54 to ensure the current conduction capability of the electrode assembly 20. The sealing ring 72 and the upper plastic 70 are installed on the upper end of the electrode post 50, and then the upper cover 46 is clamped by the external fixing part 56. Then the upper cover 46 and the cover plate body 42 are welded. The embodiments of this application address the difficulties of the prior art by proposing a square lithium-ion battery connection method. By developing a new process route, an elongated hole (first through hole 44) is pre-drilled on the cover plate body 42, and the pre-bundled and welded tabs 30 are welded to the end plate 54. This new battery structure maximizes the use of internal battery space, eliminating the need for connecting tabs and other structures, reducing the height of the tabs 30, and lowering costs. Because the connecting tabs are eliminated, weight is reduced, and the saved space can be used to increase the size of the electrode assembly 20, thereby further improving energy density. At the same time, eliminating the connecting tabs saves a step in the welding process between the electrode assembly 20 and the connecting tabs, reducing manufacturing costs.

[0045] In this embodiment, the tab 30 extends outward through the first through hole 44 on the cover plate body 42 and is welded to the end plate 54, which reduces the height of the tab 30 and decreases the cost of the battery cell. Furthermore, this embodiment eliminates the need for the folding tab space reserved in the prior art to prevent tab insertion, thus preventing internal short circuits caused by tab insertion and freeing up space for the electrode assembly 20, thereby increasing energy density.

[0046] In some embodiments, the single-mode laser fiber core diameter range includes 14-25μm, and the power range is 1000-2000W; the single-mode ring inner ring core diameter is 14-25μm, the outer ring core diameter is 50-100μm, the outer ring power is 1000-2000W, and the inner ring power is 1000-2000W; the multimode ring inner ring core diameter is 50-100μm, the outer ring core diameter is 150-600μm, the outer ring power is 1000-2000W, and the inner ring power is 2000-4000W. In practical applications, the parameters for welding end plate 54 and tab 30 using a single-mode ring laser are as follows: outer ring power 1000-2000W, inner ring power 400-800W, defocusing amount -2 to +2mm, and welding speed 300-500mm / s; the parameters for welding the second end plate 64 and second tab 32 are as follows: outer ring power 1000-2000W, inner ring power 400-800W, defocusing amount -2 to +2mm, and welding speed 300-500mm / s.

[0047] In the embodiments of this application, the tabs 30 are stacked and flatly attached to the top of the end plate 54, and then the tabs 30 are welded together with the end plate 54 by laser welding. This eliminates the need for connecting pieces, reduces the thickness of the bottom metal plate of the electrode post, and also reduces the thickness of the lower insulating component 74. The saved thickness can be used to increase the capacity of the electrode assembly 20.

[0048] Taking a battery cell 100 with a height of 100mm as an example, the existing tab space is generally 5mm-8mm. Taking a common tab space of 6mm as an example, the implementation method of this application saves tab space, which can save about 5mm of internal space, and the energy density of the battery cell 100 can be increased by 5%.

[0049] The electrode assembly 20 in this embodiment can be a wound battery cell or a stacked battery cell. The housing 10 can include a single electrode assembly 20, and the number of electrode assemblies 20 can also be 2, 3, 4, etc. In addition, the connection between the end plate 54 and the electrode post body 52 of the electrode post 50 can be integrally stamped, or it can be connected by laser welding, riveting, injection molding, etc.

[0050] This embodiment, based on the described battery cell 100, also provides an example of a battery 300. The battery 300 includes the battery cell 100 as provided in any of the above embodiments. The battery 300 can be a battery module; when there are multiple battery cells 100, the multiple battery cells 100 are arranged and fixed to form a battery module. The battery 300 can also be a battery pack, which includes a housing and battery cells 100, with the battery cells 100 or battery modules housed within the housing. The housing provides space for housing the battery cells 100 or battery modules.

[0051] This utility model also provides an electrical device 1000. For ease of explanation, the following embodiments will use a vehicle as an example to illustrate the electrical device 1000. Figure 10 This illustration shows a schematic diagram of an electrical device 1000 in an embodiment of this application when it is a vehicle. The vehicle's interior is equipped with a battery comprising multiple battery cells 100, which may be located at the bottom, front, or rear of the vehicle body 1001. The battery can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The working part of the electrical device is electrically connected to the battery to obtain electrical energy. 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, but are not limited thereto. The battery provides electrical energy support for the vehicle's operation or the operation of its internal electrical components. However, in other embodiments, the electrical device 1000 can also be a mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, and power tool, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; the working part is a unit component that can obtain electrical energy from the battery and perform corresponding work, such as the fan blade rotation unit of a fan, or the vacuuming unit of a vacuum cleaner, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and 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. This application does not impose any special limitations on the aforementioned electrical device 1000.

[0052] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A battery cell, characterized in that, include: The outer shell has a cavity and an opening; An electrode assembly is disposed in the cavity, and the end of the electrode assembly facing the opening includes a tab. Cover plate assembly, including: A cover plate body that covers the opening, the cover plate body having a first through hole; An electrode post includes an electrode post body extending along a first direction and an end plate extending along a first plane. The end plate is at least partially connected to the outer wall of the electrode post body in a circumferential direction. The end plate is disposed on the side of the cover plate body opposite to the electrode assembly. The end plate includes a first surface opposite to the electrode assembly. The electrode tab passes through a first through hole and is connected to the first surface. The first direction is the thickness direction of the cover plate body, and the first plane is perpendicular to the first direction. The upper cover connects the pole post and the cover plate body to seal the first through hole, and the pole tab is located between the upper cover and the end plate in the first direction.

2. The battery cell according to claim 1, characterized in that, Along a second direction, the edge of the end plate extends beyond or is aligned with the edge of the pole body, where the second direction is the length direction of the cover plate body; and / or Along a third direction, the end plate extends to the edge of the first through hole, and the third direction is the width direction of the cover plate body.

3. The battery cell according to claim 1, characterized in that, Along the first direction, the pole is located on the side of the cover plate body away from the electrode assembly, the end plate is connected to the end of the pole body facing the electrode assembly, and a lower insulating member is provided between the end plate and the cover plate body.

4. The battery cell according to claim 1, characterized in that, The edge of the upper cover is welded to the cover plate body, and the distance between the edge of the upper cover and the first through hole is greater than or equal to 0.1 mm.

5. The battery cell according to claim 1, characterized in that, An insulating layer is provided between the electrode tab and the cover plate body, as well as between the electrode tab and the upper cover.

6. The battery cell according to claim 1, characterized in that, The cover plate body is provided with a second through hole, the pole body passes through the second through hole, the lower insulating member disposed between the end plate and the cover plate body extends to the second through hole, and the portion of the lower insulating member located in the second through hole is located between the pole body and the cover plate body.

7. The battery cell according to claim 1, characterized in that, The cover plate assembly also includes: The upper plastic is attached to the electrode post, which also includes an external fixing member connected to one end of the electrode post body opposite to the electrode assembly. The upper plastic is sandwiched between the external fixing member and the upper cover. A sealing ring is disposed between the upper cover and the pole body.

8. The battery cell according to claim 7, characterized in that, The upper cover includes a first upper cover and a second upper cover, the electrode includes a first electrode and a second electrode, and the electrode post includes a first electrode post and a second electrode post respectively connected to the first electrode and the second electrode. The first upper cover corresponds to the first electrode and the first electrode post, and the second upper cover corresponds to the second electrode and the second electrode post.

9. The battery cell according to claim 8, characterized in that, The electrode assembly includes multiple layers of first tabs bundled into a first tab group and multiple layers of second tabs bundled into a second tab group. The end plate includes a first end plate and a second end plate corresponding to the first pole post and the second pole post, respectively. The first tab group and the second tab group are welded to the first end plate and the second end plate, respectively. The thickness of the first end plate and the second end plate is between 1 mm and 2 mm.

10. A battery, characterized in that, Includes the battery cell as described in any one of claims 1 to 9.

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