Battery monomer, battery and electric device

Abstract

A battery cell (20), a battery (100), and an electric device. A battery cell (20) includes a case (23), an electrode assembly (25), an electrode terminal (216), and a current collecting member (211). The case (23) accommodates the electrode assembly (25). The electrode assembly (25) includes a tab (251). The electrode terminal (216) is provided to the case (23). The current collecting member (211) includes a tab connection portion (2111) and a terminal connection portion (2113). And the tab connecting part (2111) is used for connecting a tab (251). The terminal connection part (2113) is used for connecting the electrode terminal (216). The terminal connecting part (2113) comprises multiple layers of sub-terminal connecting parts (21137) which are arranged in a stacked manner, each layer of sub-terminal connecting part (21137) comprises a sub-riveting part (21151), and any two adjacent sub-riveting parts (21151) are riveted and fixed.

Description

Battery cells, batteries and electrical devices Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Art

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the sustainable development of the automotive industry. For electric vehicles, battery technology is a key factor in their development.

[0003] The current collecting member is a component in the battery used to connect the electrode terminal and the electrode tab of the electrode assembly. In order to reduce the height space occupied by the current collecting member in the battery, the terminal connection portion of the current collecting member is usually designed to be bendable. However, the terminal connection portion of the existing current collecting member is mostly a single-layer integrated structure with limited bending ability. In order to facilitate bending, the thickness of the terminal connection portion cannot be made too thick, resulting in a smaller flow area of ​​the current collecting member, a larger internal resistance, and a larger temperature rise, which in turn reduces the safety of the battery.

[0004] Summary of the Invention

[0005] In view of the above problems, the present application provides a battery cell, a battery and an electrical device, which can alleviate the problem that the current collecting component has a small flow area, a large internal resistance, and a large temperature rise, thereby reducing the safety of the battery.

[0006] In a first aspect, the present application provides a battery cell. The battery cell includes an electrode assembly, a housing, an electrode terminal, and a current collecting member. The electrode assembly includes a tab. The housing is configured to accommodate the electrode assembly. The electrode terminal is disposed on the housing. The current collecting member includes a tab connection portion and a terminal connection portion. The tab connection portion is configured to connect the tab, and the terminal connection portion is configured to connect the electrode terminal to the tab connection portion. The terminal connection portion includes multiple layers of stacked sub-terminal connection portions, each layer of the sub-terminal connection portions including a sub-rivet portion, with any two adjacent sub-rivet portions being riveted together.

[0007] In the technical solution of the embodiments of the present application, the terminal connection portion of the current collecting component is designed as a stacked multi-layer sub-terminal connection portion. Compared to a current collecting component with a single-layer, integrated structure, the bonding force between the multi-layer sub-terminal connection portions is weaker, and the layers are more tolerant of deformation during bending. This makes the multi-layer sub-terminal connection portion more bendable. Given the same bending capacity, the overall thickness of the multi-layer sub-terminal connection portion (i.e., the thickness of the terminal connection portion) can be made thicker, increasing the flow area, reducing internal resistance, and lowering temperature rise, thereby improving battery safety. Furthermore, the greater degree of bending of the multi-layer sub-terminal connection portion also reduces the height space occupied by the current collecting component, increasing the energy density of the battery cell, and thus also the energy density of the battery. Furthermore, any two adjacent layers of sub-terminal connection portions are riveted together using two adjacent sub-rivet portions. Compared to welding the sub-terminal connection portions of each layer to form the terminal connection portion, this improves the positioning accuracy of the terminal connection portion during connection, eliminates the need for welding, and improves the production efficiency of the current collecting component.

[0008] In some embodiments, any two adjacent sub-riveted portions are welded together. That is, the rivets at each layer of the sub-terminal connection are welded together to strengthen the connection strength between the layers of the sub-terminal connection. This not only increases the flow area of ​​the current collecting member, but also reduces internal resistance, lowers temperature rise, and improves the safety performance of the battery cell.

[0009] In some embodiments, the terminal connecting portion is provided with a fixing structure, in which all the sub-riveting portions are stacked in sequence and cooperate with each other.

[0010] Compared to punching out multiple single-layer sub-terminal connection parts and then stacking and welding them together to form a terminal connection, stacking the sub-rivet parts of adjacent layers of sub-terminal connection parts to form a fixed structure allows for precise positioning and easy alignment. This eliminates the need for welding and improves the production efficiency of current collecting components. Compared to rolling the material into multiple layers and then cutting them to create a multi-layer terminal connection, riveting the sub-rivet parts of adjacent layers of sub-terminal connection parts reduces burrs.

[0011] In some embodiments, the fixing structure is provided at an end region of the terminal connection portion close to the electrode terminal. In this way, the terminal connection portions of each layer can be riveted together to form a terminal connection portion of an integral structure.

[0012] In some embodiments, the fixing structure is provided at an end region of the terminal connection portion close to the tab connection portion. In this way, after the sub-terminal connection portions of each layer are riveted together to form an integrated terminal connection portion, the integrated terminal connection portion can be conveniently riveted to the tab connection portion.

[0013] In certain embodiments, the fixing structure is provided at the end region of the terminal connection portion close to the electrode terminal, and at the end region of the terminal connection portion close to the tab connection portion. Thus, on the one hand, the terminal connection portions of each layer can be riveted together to form a terminal connection portion of an integrated structure; on the other hand, after the terminal connection portions of each layer are riveted together to form a terminal connection portion of an integrated structure, the terminal connection portion of the integrated structure can be conveniently riveted together with the tab connection portion; and on still another hand, the fixing structure is provided at both opposite ends of the terminal connection portion, so that the bonding force at both ends of the integrated terminal connection portion is relatively uniform, and the overall bonding is more secure.

[0014] In certain embodiments, the number of the fixing structures is one or more. When there is one fixing structure, the positioning accuracy of the sub-terminal connecting portions of any adjacent layers is ensured during riveting. When there are multiple fixing structures, the multiple fixing structures not only ensure the positioning accuracy of the sub-terminal connecting portions of any adjacent layers during riveting, but also improve the connection strength between the sub-terminal connecting portions, making them less likely to separate from each other, thereby improving the operating stability of the current collecting component.

[0015] In some embodiments, the cross-sectional shape of the fixing structure includes any one of a square, a rectangle, and a circle. The cross-sectional shape of the fixing structure is not limited and can be any one of a square, a rectangle, and a circle, which reduces the design difficulty of the terminal connection portion and simplifies the production of the current collecting component.

[0016] In certain embodiments, the terminal connection portion, when unfolded, has a first main surface and a second main surface disposed opposite each other along its thickness. The fixing structure has a recessed portion formed on one side of the first main surface, and a first protruding portion formed on the second main surface. The fixing structure, including the first protruding portion and the recessed portion, prevents misalignment during stacking when riveting the terminal connection portion, ensuring precise positioning and easy alignment. This also eliminates the need for welding processes, improving the production efficiency of the current collecting component. Furthermore, the inclusion of the first protruding portion and the recessed portion in the fixing structure can reduce burrs.

[0017] In some embodiments, the tab connection portion is disposed on a side of the terminal connection portion close to the second main surface, the tab connection portion is provided with a first receiving portion, and the first protrusion is received in the first receiving portion. The first protrusion is received in the first receiving portion and serves to position the terminal connection portion when connected to the tab connection portion.

[0018] In certain embodiments, the terminal connection portion is fixedly connected to the tab connection portion via the first protrusion. The first protrusion is fixedly connected to the first accommodating portion, thereby achieving fixed connection of the terminal connection portion to the tab connection portion via the first protrusion. Compared to a case where the terminal connection portion is connected to the tab connection portion using a welding process, this improves the positioning accuracy of the terminal connection portion when connected to the tab connection portion, eliminates the need for a welding process, and improves the production efficiency of the current collecting component.

[0019] In some embodiments, each of the sub-rivet portions has a sub-protrusion and a sub-recess, each of the sub-protrusions protrudes toward the second main surface, each of the sub-recesses is recessed from the first main surface toward the second main surface, and the sub-protrusion of one of the two adjacent sub-rivet portions is accommodated and fixedly connected to the sub-recess of the other sub-rivet portion.

[0020] Compared to punching out multiple single-layer sub-terminal connecting parts and then stacking and welding them together to form a terminal connection, riveting the sub-protrusions and sub-recesses of adjacent layers of sub-terminal connecting parts prevents misalignment during stacking, provides precise positioning, and facilitates alignment. It also eliminates the need for welding, improving the production efficiency of current collecting components. Compared to rolling material into multiple layers and then cutting to create a multi-layer terminal connection, riveting the sub-protrusions and sub-recesses of adjacent layers of sub-terminal connecting parts reduces burrs.

[0021] In some embodiments, the terminal connection portion is provided with a second receiving portion, and the tab connection portion is provided with a second protrusion, which is received in the second receiving portion. The second protrusion being received in the second receiving portion can improve the positioning accuracy when the terminal connection portion and the tab connection portion are connected.

[0022] In certain embodiments, the tab connection portion is fixedly connected to the terminal connection portion via the second protrusion. The second protrusion is fixedly connected to the second accommodating portion, thereby achieving fixed connection of the tab connection portion to the terminal connection portion via the second protrusion. Compared to connecting the tab connection portion to the terminal connection portion using a welding process, this improves the positioning accuracy of the tab connection portion and the terminal connection portion, eliminates the need for a welding process, and improves the production efficiency of the current collecting component.

[0023] In certain embodiments, the terminal connection portion and the tab connection portion are at least partially welded. This means that welding is performed between the terminal connection portion and the tab connection portion to strengthen the connection. This not only increases the flow area of ​​the current collecting component, reduces internal resistance, lowers temperature rise, and improves the safety performance of the battery cell, but also strengthens the connection between the terminal connection portion and the tab connection portion, making them less likely to separate, thereby improving the operational stability of the current collecting component.

[0024] In certain embodiments, the weld mark formed between the terminal connection portion and the tab connection portion is located outside the fixing structure. This location increases the flow area of ​​the current collecting component, reduces internal resistance, lowers temperature rise, and improves the safety performance of the battery cell. It also strengthens the connection between the terminal connection portion and the tab connection portion without damaging the riveted joint, making them less likely to separate, thereby improving the operational stability of the current collecting component.

[0025] In certain embodiments, the terminal connection portion is disposed in a bent manner between the tab connection portion and the electrode terminal. This bent arrangement of the terminal connection portion between the tab connection portion and the electrode terminal can reduce the height space occupied by the current collecting member in the battery cell, making the battery cell structure more compact. Furthermore, at the same battery cell height, more space can be freed up for the electrode assembly, thereby increasing the energy density of the battery cell.

[0026] In a second aspect, the present application provides a battery comprising the battery cell described in any of the above embodiments.

[0027] In the technical solution of the embodiment of the present application, the battery utilizes the battery cell of the embodiment of the first aspect. In this battery cell, the multi-layer sub-terminal connection portion of the current collecting component has a stronger bending ability and is less prone to breakage, thereby ensuring the operational stability of the battery. Furthermore, while maintaining the same bending ability, the overall thickness of the multi-layer sub-terminal connection portion can be made thicker, increasing the flow area, reducing internal resistance, and lowering temperature rise, thereby improving battery safety. Furthermore, the greater degree of bending of the multi-layer sub-terminal connection portion also reduces the height space occupied by the current collecting component, increasing the energy density of the battery cell, and thus, the energy density of the battery.

[0028] In a third aspect, the present application provides an electrical device comprising the battery described in any one of the above embodiments, wherein the battery is used to provide electrical energy.

[0029] In the technical solution of the embodiment of the present application, an electrical device utilizes the battery of the embodiment of the second aspect. In the battery cells of this battery, the multi-layer sub-terminal connection portion of the current collecting component has a stronger bending capacity and is less prone to breakage, thereby ensuring the operational stability of the electrical device. Furthermore, while maintaining the same bending capacity, the overall thickness of the multi-layer sub-terminal connection portion can be made thicker, increasing the flow area, reducing internal resistance, and lowering temperature rise, thereby improving battery safety. Furthermore, the greater degree of bending of the multi-layer sub-terminal connection portion reduces the height space occupied by the current collecting component, increasing the energy density of the battery cells, thereby also increasing the energy density of the battery, and thus increasing the battery life of the electrical device.

[0030] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0032] FIG1 is a schematic structural diagram of a vehicle according to some embodiments of the present application;

[0033] FIG2 is a schematic diagram of the exploded structure of a battery according to some embodiments of the present application;

[0034] FIG3 is a schematic diagram of the three-dimensional structure of a battery cell according to some embodiments of the present application;

[0035] FIG4 is a schematic diagram of the three-dimensional structure of a top cover assembly according to some embodiments of the present application;

[0036] FIG5 is a schematic diagram of the exploded structure of a top cover assembly according to some embodiments of the present application;

[0037] FIG6 is a schematic plan view of the top cover assembly according to some embodiments of the present application;

[0038] FIG7 is a schematic cross-sectional view of the top cover assembly shown in FIG6 along line VII-VII;

[0039] FIG8 is a schematic cross-sectional view of the top cover assembly shown in FIG6 along line VIII-VIII;

[0040] FIG9 is a schematic diagram of the three-dimensional structure of a current collecting component according to some embodiments of the present application;

[0041] FIG10 is a schematic diagram of the exploded structure of a current collecting component according to some embodiments of the present application;

[0042] FIG11 is a schematic diagram of the three-dimensional structure of a terminal connection portion in a current collecting component in some embodiments of the present application;

[0043] FIG12 is a schematic diagram of the planar structure of a current collecting component according to some embodiments of the present application;

[0044] FIG13 is a schematic cross-sectional view of the current collecting member shown in FIG12 along line XIII-XIII;

[0045] FIG14 is a schematic diagram of a planar structure of a current collecting component according to some embodiments of the present application;

[0046] FIG15 is a schematic cross-sectional view of the current collecting member shown in FIG14 along line XV-XV;

[0047] FIG16 is a schematic diagram of the three-dimensional structure of the current collecting component in some embodiments of the present application.

[0048] The accompanying drawings in the specific embodiments are as follows:

[0049] Vehicles 1000;

[0050] Battery 100, controller 200, motor 300;

[0051] Box body 10, first part 11, second part 12;

[0052] Battery cell 20, top cover assembly 21, current collecting member 211, tab connection portion 2111, connection area 21111, welding area 21113, terminal connection portion 2113, first connection section 21131, second connection section 21133, bending section 21135, fixing structure 2115, sub-rivet portion 21151, first accommodating portion 2117, second accommodating portion 2118, sub-accommodating portion 21181, second protrusion 2119, sub-terminal connection portion 21137, top cover sheet 212, first insulating member 213, second insulating member 214, connector 215, electrode terminal 216, sealing member 217; outer shell 23; electrode assembly 25. DETAILED DESCRIPTION

[0053] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0055] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0056] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0057] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0058] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0059] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

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

[0061] Currently, market developments indicate that power batteries are becoming increasingly widely used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As power battery applications continue to expand, market demand is also growing.

[0062] The inventors have noticed that in current batteries, the tabs of the electrode assembly are flattened, and after the current collecting member and the tabs are welded, the current collecting member is bent and electrically connected to the electrode terminal to achieve current extraction. This places high demands on the current-carrying capacity of the current collecting member. However, in order to facilitate bending and process welding (welding of the current collecting member and the tabs of the electrode assembly), the terminal connection portion of the current collecting member cannot be made too thick, so the flow area S of the terminal connection portion is very small. In addition, the bending process requires the terminal connection portion to be folded three times, so the length L of the terminal connection portion is also relatively long. According to the resistance calculation formula R = ρ * L / S, it can be seen that the internal resistance of the terminal connection portion will become relatively large, and both the flow and internal resistance requirements cannot meet the requirements of power batteries.

[0063] To alleviate the problem of the current collecting component's small flow area, high internal resistance, and high temperature rise, which in turn reduces battery safety, the inventors discovered that the terminal connection portion of the current collecting component can be designed as a stacked multi-layer sub-terminal connection. Compared to a single-layer, integrated current collecting component, the bonding force between the multi-layer sub-terminal connections is weaker, and the layers are more tolerant of deformation during bending. This makes the multi-layer terminal connection more flexible. Given the same bending capacity, the overall thickness of the multi-layer terminal connection can be thicker, resulting in a larger flow area, lower internal resistance, and lower temperature rise, thereby improving battery safety.

[0064] Based on the above considerations, in order to design the terminal connection portion of the current collecting component into a stacked multi-layer sub-terminal connection portion, the inventors also discovered that: the multi-layer terminal connection portion obtained by stacking multiple layers of material and then cutting will produce a large number of edge burrs, while the multi-layer terminal connection portion obtained by punching out multiple single-layer sub-terminal connections and then stacking them and welding them will be misaligned and have low welding efficiency. Both of these production methods are not suitable for mass production. After in-depth research, the inventors designed a current collecting component for battery cells. The terminal connection portion of the current collecting component is designed as a stacked multi-layer sub-terminal connection portion. The sub-terminal connection portions of any two adjacent layers are riveted together, eliminating burrs, achieving high positioning accuracy, easy alignment, and eliminating the need for welding processes. This improves the production efficiency of the terminal connection portion and facilitates mass production.

[0065] The battery cells disclosed in the embodiments of the present application can be used in electrical devices that use batteries as power sources or various energy storage systems that use batteries as energy storage elements. Electrical devices may include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery-powered vehicles, electric vehicles, ships, spacecraft, and the like. Electric toys may include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, and spacecraft may include airplanes, rockets, space shuttles, and spacecraft, among others.

[0066] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0067] Please refer to Figure 1, which is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0068] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0069] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 provides a storage space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap each other and together define a storage space for the battery cell 20. The second portion 12 can be a hollow structure with one end open. The first portion 11 can be a plate-like structure, with the first portion 11 overlapping the open side of the second portion 12, so that the first portion 11 and the second portion 12 together define a storage space. Alternatively, the first portion 11 and the second portion 12 can each be a hollow structure with one end open, with the open side of the first portion 11 overlapping the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0070] In the battery 100, there may be multiple battery cells 20, which may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. Multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection to form a battery module, which is then connected in series, in parallel, or in a hybrid connection to form a complete battery module, which is then housed within the housing 10. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0071] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 can be cylindrical, flat, rectangular, or in other shapes. A battery cell 20 is the smallest unit that makes up the battery 100. In this application, the battery cell 20 is described using a cylindrical battery as an example.

[0072] Please refer to Figure 3, which shows a battery cell 20 according to some embodiments of the present application. The battery cell 20 includes a shell 23, an electrode assembly 25, an electrode terminal 216 and a current collecting member 211. The shell 23 is used to accommodate the electrode assembly 25. The electrode assembly 25 includes a tab 251. The electrode terminal 216 is provided on the shell 23. In conjunction with Figures 9 and 10, the current collecting member 211 includes a tab connecting portion 2111 and a terminal connecting portion 2113. The tab connecting portion 2111 is used to connect the tab 251. The terminal connecting portion 2113 is used to connect the electrode terminal 216 and the tab connecting portion 2111. In conjunction with Figure 13, the terminal connecting portion 2113 includes a plurality of stacked sub-terminal connecting portions 21137, each layer of sub-terminal connecting portions 21137 includes a sub-rivet portion 21151, and any two adjacent sub-rivet portions 21151 are riveted together.

[0073] The housing 23 can be cylindrical in structure, and a cavity is formed inside the housing 23 for accommodating the electrode assembly 25 and the electrolyte. Openings are provided at both ends of the housing 23, allowing the electrode assembly 25 to be placed into the cavity of the housing 23 through the openings. The housing 23 can be made of a metal material, such as aluminum or an aluminum alloy, or an insulating material, such as plastic or rubber.

[0074] The electrode assembly 25 includes a pole piece unit and a tab 251 extending from at least one end surface. Specifically, along the height direction (H) of the battery cell 20, the pole piece unit has two oppositely disposed end surfaces. In the battery cell 20, tabs 251 extend from each end surface of the pole piece unit, respectively, forming a positive tab and a negative tab. The pole piece unit includes a negative electrode sheet, a positive electrode sheet, and a separator. The separator is located between adjacent negative and positive electrode sheets to separate the negative and positive electrodes.

[0075] In one possible design, the negative electrode sheet, separator, and positive electrode sheet are sequentially stacked and wound to form a electrode sheet unit of the electrode assembly 25. This electrode sheet unit is a wound structure. Furthermore, the electrode sheet unit has gaps after formation, allowing electrolyte to enter the electrode sheet unit through the gaps and soak the negative and positive electrode sheets.

[0076] The negative electrode sheet includes a negative electrode current collector (e.g., copper foil) and a negative electrode active material layer (e.g., carbon or silicon) coated on the surface of the negative electrode current collector. The positive electrode sheet includes a positive electrode current collector (e.g., aluminum foil) and a positive electrode active material layer (e.g., ternary material, lithium iron phosphate, or lithium cobalt oxide) coated on the surface of the positive electrode current collector. The negative electrode tab is connected to the negative electrode sheet and extends from the electrode unit. The negative electrode tab can be directly cut from the negative electrode current collector. The positive electrode tab is connected to the positive electrode sheet and extends from the electrode unit. The positive electrode tab can be directly cut from the positive electrode current collector.

[0077] The electrode terminals 216 are functional components that can be used to conduct current from the electrode assembly 25 to the outside of the battery 100, thereby outputting or inputting electrical energy from the battery cell 20. The electrode terminals 216 include a positive electrode terminal and a negative electrode terminal, which are located at either end of the electrode unit. One end of each electrode terminal 216 extends into the interior of the battery cell 20, while the other end is exposed to the outside of the battery cell 20 and can be connected to an external electrical connector.

[0078] The current collecting member 211 is used to seal the opening of the battery cell 20, connect the tab 251 of the electrode assembly 25 within the opening, and connect to the electrode terminal 216 of the battery cell 20. The current collecting member 211 must be made of a conductive metal material to ensure that it can serve as a good conductor between the tab 251 and the electrode terminal 216 after connection. The current collecting member 211 used in the embodiments of the present application can be applied to cylindrical battery cells 20, as well as battery cells 20 of other shapes, such as rectangular parallelepiped.

[0079] Referring to Figures 3, 9, and 10, the tab connection portion 2111 is the portion of the current collecting member 211 that seals the opening of the battery cell 20's housing 23. The tab connection portion 2111 can be configured to have a shape that matches the opening of the battery cell 20's housing 23, such as a substantially circular shape. The tab connection portion 2111 is also used for welding to the tab 251 of the electrode assembly 25. The welding region 21113 of the tab connection portion 2111 is the area for welding to the tab 251 of the electrode assembly 25. The area and location of the tab connection portion 2111 can be adjusted to meet the requirements of welding the tab 251. The connection area 21111 of the tab connection portion 2111 is an area for connecting to the terminal connection portion 2113. The connection area 21111 of the tab connection portion 2111 is located at a position that does not affect the welding between the tab 251 and the tab connection portion 2111. That is, the connection area 21111 of the tab connection portion 2111 is located in the area remaining after the tab connection portion 2111 is removed from the welding area 21113. The connection area 21111 may occupy a portion of the area of ​​the tab connection portion 2111 after the welding area 21113 is removed, for example, occupying the left or right area of ​​the tab connection portion 2111 after the welding area 21113 is removed. Of course, the connection area 21111 may also occupy the entire area of ​​the tab connection portion 2111 after the welding area 21113 is removed, for example, occupying the left and right areas of the tab connection portion 2111 after the welding area 21113 is removed. In addition, the current collecting member 211 provided in the embodiment of the present application does not limit the shapes of the welding area 21113 and the connection area 21111 of the tab connection portion 2111 .

[0080] Continuing to refer to Figures 5, 9, and 10, the terminal connection portion 2113 is a component on the current collecting member 211 used to connect to the electrode terminal 216. The terminal connection portion 2113 is connected to the connection area 21111 to ensure that the current collecting member 211 functions as a current conducting component. The terminal connection portion 2113 and the tab connection portion 2111 can be made of the same conductive metal material, or they can be made of different conductive metal materials, as long as the current collecting member 211 can function as a good conductor between the tab 251 and the electrode terminal 216 after being connected to the tab 251 and the electrode terminal 216, respectively. The terminal connection portion 2113 is longer than the tab connection portion 2111. Specifically, referring to Figure 8, the terminal connection portion 2113 includes a first connecting section 21131, a second connecting section 21133, and a bent section 21135 located between the first connecting section 21131 and the second connecting section 21133. The first connecting section 21131 and the second connecting section 21133 are located at opposite ends of the terminal connecting portion 2113 after expansion. The first connecting section 21131 is used to connect to the electrode terminal 216, while the second connecting section 21133 is used to connect to the tab connecting portion 2111 and is located in the connection area 21111. The bending section 21135 is the area of ​​the terminal connecting portion 2113 that connects the first connecting section 21131 and the second connecting section 21133 and has excellent bending properties. The bending section 21135 can bend at the location where it connects to the first connecting section 21131 and can also bend at the location where it connects to the second connecting section 21133, resulting in a Z-shape in the current collecting member 211 after bending.

[0081] The terminal connection portion 2113 includes multiple layers of stacked sub-terminal connection portions 21137. Each layer of sub-terminal connection portions 21137 is identical, allowing for easy mass production using the same process. The multiple layers of sub-terminal connection portions 21137 are stacked on top of each other and secured together using a bonding process to form a single, integrated terminal connection portion 2113. Specifically, referring to Figure 13, each layer of sub-terminal connection portions 21137 includes a sub-rivet portion 21151, with any two adjacent sub-rivet portions 21151 being riveted together.

[0082] Riveting is a process or method of connecting two components by drilling holes in them, inserting rivets, and then using a rivet gun to rivet them together. However, the riveted connection between any two adjacent layers of sub-terminal connecting parts 21137 in this application does not use rivets. Instead, the riveting between any two adjacent layers of sub-terminal connecting parts 21137 is achieved by directly riveting the sub-terminal connecting parts 21137 together to achieve the connection between the sub-terminal connecting parts 21137 of each layer.

[0083] In the technical solution of the embodiment of the present application, the terminal connection portion 2113 of the current collecting member 211 is designed as a stacked multi-layer sub-terminal connection portion 21137. Compared to a single-layer, integrated current collecting member, the bonding force between the multi-layer sub-terminal connection portions 21137 is weaker, allowing for greater tolerance of deformation between the layers during bending. This results in a stronger bending capability for the multi-layer sub-terminal connection portion 21137. Given the same bending capability, the overall thickness of the multi-layer sub-terminal connection portion 21137 (i.e., the thickness of the terminal connection portion 2113) can be made thicker, increasing the flow area, reducing internal resistance, and lowering temperature rise, thereby improving the safety of the battery 100 (shown in FIG. 2 ). Furthermore, the greater degree of bending of the multi-layer sub-terminal connection portion 21137 also reduces the height space occupied by the current collecting member 211, increasing the energy density of the battery cell 20, and thus, the energy density of the battery 100. At the same time, any two adjacent layers of sub-terminal connecting parts 21137 are riveted and fixed by using two adjacent sub-rivet parts 21151 to achieve riveted connection. Compared with the welding process used to connect the sub-terminal connecting parts of each layer, the positioning accuracy of the terminal connecting part 2113 when connected is improved, and no welding process is required, thereby improving the production efficiency of the current collecting component 211.

[0084] According to some embodiments of the present application, as shown in FIG3 , the battery cell 20 optionally further includes a top cover assembly 21 . The electrode assembly 25 is housed within the housing 23 . A positive electrode tab and a negative electrode tab are provided at opposite ends of the electrode assembly 25 . The top cover assembly 21 covers the openings at both ends of the housing 23 , and both the positive electrode tab and the negative electrode tab are connected to the tab connection portion 2111 (shown in FIG9 ) of the current collecting member 211 in the top cover assembly 21 .

[0085] The top cover assembly 21 is a component that covers the opening of the outer shell 23 of the battery cell 20 and provides a closed space for the electrode assembly 25 and electrolyte located inside the outer shell 23. The electric energy of the electrode assembly 25 is led out to the outside through the electrode terminal 216 of the top cover assembly 21.

[0086] The top cap assembly 21 is located at opposite ends of the battery cell 20. The multi-layer sub-terminal connection portion 21137 has a stronger bending capability. Given the same bending capability, the overall thickness of the multi-layer sub-terminal connection portion 21137 can be made thicker, increasing the flow area of ​​the current collecting member 211, reducing internal resistance, and lowering temperature rise, thereby improving the safety of the battery 100 (shown in Figure 2). Furthermore, the greater degree of bending of the multi-layer sub-terminal connection portion 21137 reduces the height space occupied by the current collecting member 211 in the top cap assembly 21 at both ends. Given the same battery cell 20 height, more space is freed up at both ends for the positive and negative electrodes, further increasing the energy density of the battery cell 20.

[0087] According to some embodiments of the present application, optionally, referring to Figures 4 and 5, the top cover assembly 21 includes a current collecting component 211, a top cover sheet 212, a first insulating member 213, a second insulating member 214, a connecting member 215 and an electrode terminal 216. Specifically, referring to Figures 5 to 8, the top cover sheet 212 includes a first side and a second side opposite to each other. The first insulating member 213 is mounted on the first side of the top cover sheet 212. The second insulating member 214 is mounted on the second side of the top cover sheet 212. The connecting member 215 is mounted on the side of the first insulating member 213 facing away from the top cover sheet 212. The current collecting component 211 is mounted on the side of the second insulating member 214 facing away from the top cover sheet 212. The electrode terminal 216 passes through the first connecting section 21131 of the current collecting member 211 , the second insulating member 214 , the top cover 212 , the first insulating member 213 and the connecting member 215 . The opposite ends of the electrode terminal 216 are respectively connected to the connecting member 215 and the first connecting section 21131 of the current collecting member 211 .

[0088] Please refer to Figures 3 and 4 together. The top cover sheet 212 refers to a component that covers the opening of the outer shell 23 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the top cover sheet 212 can be adapted to the shape of the opening of the outer shell 23 to match the outer shell 23. Optionally, the top cover sheet 212 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the top cover sheet 212 is not easily deformed when squeezed or collided, so that the battery cell 20 can have higher structural strength and improved safety performance. The first side of the top cover sheet 212 is the side facing away from the interior of the outer shell 23, and the second side of the top cover sheet 212 is the side facing the interior of the outer shell 23.

[0089] Please refer to Figure 5. The connector 215 is a component on the top cover sheet 212 used to rivet one end of the electrode terminal 216. The connector 215 can be made of aluminum. The first insulating member 213 and the second insulating member 214 are components provided on the top cover sheet 212 to perform electrical insulation. The first insulating member 213 and the second insulating member 214 are both made of insulating materials, such as plastic, rubber, etc. The first insulating member 213 is located on the first side of the top cover sheet 212, and is used to support the connector 215 and electrically insulate the connector 215 from the top cover sheet 212. The second insulating member 214 is located on the second side of the top cover sheet 212, and is used to accommodate the current collecting component 211 and electrically insulate the current collecting component 211 from the top cover sheet 212. The provision of the first insulating member 213 and the second insulating member 214 can reduce the risk of short circuit.

[0090] Referring to Figures 7 and 8 , the opposite ends of the electrode terminal 216 are connected to the connector 215 and the first connecting section 21131 of the current collecting member 211, respectively. The second connecting section 21133 of the current collecting member 211 is connected to the tab 251 of the electrode assembly 25 via the tab connection portion 2111. This allows the current from the electrode assembly 25 to be directed sequentially through the tab 251, the current collecting member 211, and the electrode terminal 216 to the connector 215 on the first side. A first insulating member 213 and a second insulating member 214 are disposed on opposite sides of the top cover sheet 212 to insulate the top cover sheet 212 and reduce the risk of short circuits.

[0091] According to some embodiments of the present application, optionally, referring to Figures 5 and 7, the top cover assembly 21 also includes a seal 217, which is sleeved on the electrode terminal 216 and located between the top cover sheet 212 and the electrode terminal 216, for sealing the gap between the top cover sheet 212 and the electrode terminal 216.

[0092] The seal 217 is a functional component used to seal and prevent leakage of the electrolyte within the battery 100. The seal 217 can be made of an elastic material such as rubber or plastic. The seal 217 can be in the shape of a circular ring, a square ring, or the like, as long as it matches the shape of the outer peripheral wall of the electrode terminal 216 and can be inserted into the gap between the top cover sheet 212 and the electrode terminal 216. The seal 217 is located between the electrode terminal 216 and the top cover sheet 212 to fill the gap and prevent leakage of the electrolyte within the battery cell 20.

[0093] According to some embodiments of the present application, as shown in FIG13 , any two adjacent sub-rivet portions 21151 are optionally connected by welding. Specifically, the rivet locations of the sub-terminal connection portions 21137 of each layer are reinforced by welding. This not only improves the connection strength between the sub-terminal connection portions 21137 of each layer, but also increases the flow area of ​​the current collecting member 211, reduces internal resistance, lowers temperature rise, and improves the safety performance of the battery cell 20.

[0094] According to some embodiments of the present application, optionally referring to Figures 10 to 13 , the terminal connection portion 2113 is provided with a fixing structure 2115 , in which all sub-rivet portions 21151 are stacked and matched with each other. That is, multiple sub-rivet portions 21151 are stacked to form a fixing structure 2115 .

[0095] The fixing structure 2115 is used to position and secure two components to be connected. The sub-rivet portions 21151 are also used to position and secure two components to be connected. The multiple sub-rivet portions 21151 cooperate with each other to position and securely connect the two components to be connected, specifically, to position and securely connect two adjacent sub-terminal connecting portions 21137.

[0096] Compared to punching out multiple single-layer sub-terminal connecting portions and then stacking and welding them together to form a terminal connection, stacking the sub-rivet portions 21151 of adjacent layers of sub-terminal connecting portions 21137 to form a fixed structure 2115 allows for precise positioning and easy alignment. This eliminates the need for welding and improves the production efficiency of the current collecting member 211. Compared to rolling a material into multiple layers and then cutting it to create a multi-layer terminal connection, riveting the sub-rivet portions 21151 of adjacent layers of sub-terminal connecting portions 21137 can reduce burrs.

[0097] According to some embodiments of the present application, optionally, referring to Figures 5, 13, and 15, a fixing structure 2115 is provided at an end region of the terminal connecting portion 2113 near the electrode terminal 216. That is, the fixing structure 2115 is provided at the first connecting section 21131 of the terminal connecting portion 2113. In this way, the sub-terminal connecting portions 21137 of each layer can be riveted together to form a terminal connecting portion 2113 of an integral structure.

[0098] According to some embodiments of the present application, optionally, referring to Figures 5 and 13 , a fixing structure 2115 is provided at an end region of the terminal connecting portion 2113 near the tab connecting portion 2111. That is, the fixing structure 2115 is provided at the second connecting section 21133 of the terminal connecting portion 2113. In this way, after the sub-terminal connecting portions 21137 of each layer are riveted together to form an integrated terminal connecting portion 2113, the integrated terminal connecting portion 2113 can be conveniently riveted to the tab connecting portion 2111.

[0099] According to some embodiments of the present application, optionally, referring to FIG5 and FIG13 , a fixing structure 2115 is provided at an end region of the terminal connection portion 2113 close to the electrode terminal 216, and at an end region of the terminal connection portion 2113 close to the tab connection portion 2111. That is, the first connection segment 21131 of the terminal connection portion 2113 is provided with the fixing structure 2115, and the second connection segment 21133 of the terminal connection portion 2113 is also provided with the fixing structure 2115. In this way, on the one hand, the sub-terminal connecting parts 21137 of each layer can be riveted to form a terminal connecting part 2113 of an integral structure; on the other hand, after the sub-terminal connecting parts 21137 of each layer are riveted to form a terminal connecting part 2113 of an integral structure, the terminal connecting part 2113 of the integral structure can be conveniently riveted and connected to the tab connecting part 2111; on the other hand, the opposite ends of the terminal connecting part 2113 are provided with a fixing structure 2115, so that the bonding force at both ends of the terminal connecting part 2113 of the integral structure is relatively uniform, and the overall bonding is more firmly.

[0100] According to some embodiments of the present application, optionally, referring to FIG. 11 , FIG. 15 and FIG. 16 , the number of the fixing structures 2115 is one or more.

[0101] Referring to Figures 14 and 15 , when there is only one fixing structure 2115, the fixing structure 2115 can be located in the first connecting section 21131 of the terminal connecting portion 2113 (as shown in Figure 15 ), the second connecting section 21133 of the terminal connecting portion 2113, or the bent section 21135 of the terminal connecting portion 2113, without limitation. Regardless of where the fixing structure 2115 is located on the terminal connecting portion 2113, the positioning accuracy of the sub-terminal connecting portions 21137 of any adjacent layers can be guaranteed during riveting.

[0102] Please refer to Figures 11 and 16. When there are multiple fixing structures 2115, the multiple fixing structures 2115 can be all set in the first connecting section 21131 of the terminal connecting part 2113, or all set in the second connecting section 21133 of the terminal connecting part 2113, or all set in the bending section 21135 of the terminal connecting part 2113. Alternatively, a portion of the multiple fixing structures 2115 is arranged on the first connecting section 21131 of the terminal connecting portion 2113, and the rest is arranged on the second connecting section 21133 of the terminal connecting portion 2113, as shown in Figures 11 and 16; or, a portion of the multiple fixing structures 2115 is arranged on the first connecting section 21131 of the terminal connecting portion 2113, and the rest is arranged on the bending section 21135 of the terminal connecting portion 2113; or, a portion of the multiple fixing structures 2115 is arranged on the second connecting section 21133 of the terminal connecting portion 2113, and the rest is arranged on the bending section 21135 of the terminal connecting portion 2113; or again, a portion of the multiple fixing structures 2115 is arranged on the first connecting section 21131 of the terminal connecting portion 2113, another portion is arranged on the second connecting section 21133 of the terminal connecting portion 2113, and another portion is arranged on the bending section 21135 of the terminal connecting portion 2113. No matter where the multiple fixing structures 2115 are arranged on the terminal connecting part 2113, they can not only ensure the positioning accuracy of the sub-terminal connecting parts 21137 of any adjacent layers when riveting, but also improve the connection strength between the sub-terminal connecting parts 21137, making them less likely to detach from each other, thereby improving the working stability of the collecting component 211.

[0103] According to some embodiments of the present application, optionally, referring to FIG. 11 , the cross-sectional shape of the fixing structure 2115 includes any one of a square, a rectangle, and a circle.

[0104] Referring to Figures 11, 13, and 15, the cross-section of the fixing structure 2115 is the cross-section of the sub-rivet portion 21151, i.e., a plane obtained by cutting the sub-rivet portion 21151 by a plane parallel to the upper surface of the sub-terminal connecting portion 21137. The cross-sectional shape of the fixing structure 2115 is not limited and can be square, rectangular, circular, or any other polygonal shape. This reduces the design difficulty of the terminal connecting portion 2113 and simplifies the fabrication of the current collecting member 211.

[0105] According to some embodiments of the present application, optionally, referring to Figures 11 and 16, there are multiple fixing structures 2115, and a portion of the multiple fixing structures 2115 is arranged in the first connecting section 21131 of the terminal connecting portion 2113, and the remaining portion is arranged in the second connecting section 21133 of the terminal connecting portion 2113, the cross-sectional shapes of the multiple fixing structures 2115 may be the same or different.

[0106] Referring to Figures 11 to 13 , in one example, the cross-sectional shapes of the multiple fixing structures 2115 are identical. Specifically, the cross-sectional shape of the fixing structure 2115 on the first connecting section 21131 of the terminal connecting portion 2113 is rectangular, and the cross-sectional shape of the fixing structure 2115 on the second connecting section 21133 of the terminal connecting portion 2113 is also rectangular. Designing the cross-sectional shapes of the multiple fixing structures 2115 to be identical simplifies the manufacturing process of the terminal connecting portion 2113.

[0107] Referring to Figure 16 , in another example, the cross-sectional shapes of the multiple fixing structures 2115 differ at least in part. Specifically, the fixing structure 2115 on the first connecting section 21131 of the terminal connecting portion 2113 has a rectangular cross-sectional shape, while the fixing structure 2115 on the second connecting section 21133 of the terminal connecting portion 2113 has a partially rectangular cross-sectional shape and a partially circular cross-sectional shape. The different cross-sectional shapes of the multiple fixing structures 2115 facilitate positioning during riveting, prevent misalignment, and provide a foolproof effect.

[0108] According to some embodiments of the present application, optionally referring to Figures 13 and 15 , the terminal connecting portion 2113, when unfolded, has a first main surface 21138 and a second main surface 21139 disposed opposite each other along its thickness direction. The fixing structure 2115 has a concave portion formed on one side of the first main surface 21138, and a first convex portion formed on the second main surface 21139.

[0109] Among them, the first main surface 21138 is the partial area remaining after removing the concave part of the surface of the terminal connection part 2113 facing away from the tab connection part 2111, and the second main surface 21139 is the partial area remaining after removing the first convex part of the surface of the terminal connection part 2113 facing the tab connection part 2111.

[0110] In one example, the first protrusion is a structure formed by stamping the flat sheet-like terminal connection portion 2113 so as to protrude outward relative to the second main surface 21139. Correspondingly, the concave portion is a spatial structure formed by stamping the flat sheet-like terminal connection portion 2113 so as to be concave relative to the first main surface 21138, as shown in Figures 13 and 15. In another example, the concave portion is still a spatial structure formed by stamping the flat sheet-like terminal connection portion 2113 so as to be concave relative to the first main surface 21138, while the first protrusion does not protrude outward relative to the second main surface 21139 but is instead flush with the second main surface 21139. The first protrusion is defined only relative to the concave portion.

[0111] The fixing structure 2115 includes a first protrusion and a recess. This prevents misalignment during stacking when riveting the terminal connection portion 2113, ensuring precise positioning and easy alignment. This eliminates the need for welding, improving the production efficiency of the current collecting member 211. Furthermore, the inclusion of the first protrusion and recess in the fixing structure 2113 can reduce burrs.

[0112] According to some embodiments of the present application, optionally, referring to Figures 12 and 13, the tab connection portion 2111 is disposed on a side of the terminal connection portion 2113 close to the second main surface 21139, and the tab connection portion 2111 is provided with a first accommodating portion 2117, and the first protrusion of the fixing structure 2115 is accommodated in the first accommodating portion 2117. The first protrusion of the fixing structure 2115 is accommodated in the first accommodating portion 2117, which can play a positioning role when the terminal connection portion 2113 is connected to the tab connection portion 2111.

[0113] The first accommodating portion 2117 can be a through hole or a groove. The location of the first accommodating portion 2117 corresponds to the location of the fixing structure 2115 on the second connecting segment 21133, and the number of first accommodating portions 2117 corresponds to the number of fixing structures 2115 on the second connecting segment 21133. Specifically, when there is one fixing structure 2115 on the second connecting segment 21133, there is also one first accommodating portion 2117; when there are multiple fixing structures 2115 on the second connecting segment 21133, there are also multiple first accommodating portions 2117.

[0114] Furthermore, since the cross-sectional shape of the fixing structure 2115 is not restricted and can be any of square, rectangular, and circular, the cross-sectional shape of the first accommodating portion 2117 is also not restricted and can be any of the corresponding square, rectangular, and circular shapes. The only requirement is that the cross-sectional shape of the fixing structure 2115 matches the cross-sectional shape of the corresponding first accommodating portion 2117. This reduces the design difficulty of the tab connection portion 2111 and further simplifies the fabrication of the current collecting component 211.

[0115] According to some embodiments of the present application, optionally, referring to FIG. 12 and FIG. 13 , the terminal connection portion 2113 is fixedly connected to the tab connection portion 2111 via the first protrusion.

[0116] At this time, the first accommodating portion 2117 is also a structure for positioning and fixing the two components to be connected when they are connected to each other. The fixing structure 2115 and the first accommodating portion 2117 cooperate with each other to position and / or fix the two components to be connected, that is, to position and / or fix the tab connection portion 2111 and the terminal connection portion 2113. When the first protrusion of the fixing structure 2115 is fixedly connected (riveted) to the first accommodating portion 2117, the terminal connection portion 2113 can be connected to the tab connection portion 2111 by riveting. Compared with the terminal connection portion 2113 being connected to the tab connection portion 2111 by welding, the positioning accuracy of the terminal connection portion 2113 when connected to the tab connection portion 2111 is improved, and no welding process is required, thereby improving the production efficiency of the current collecting component 211.

[0117] At the same time, the number of first accommodating portions 2117 can also be greater than the number of fixing structures 2115 on the second connecting section 21133. On the one hand, if one of the first accommodating portions 2117 is damaged, the fixing structure 2115 can also be riveted to the other extra first accommodating portions 2117; on the other hand, when the installation of other parts in the battery cell 20 needs to be considered, the terminal connecting portion 2113 and the pole tab connecting portion 2111 may need to be staggered in the width direction. Then, riveting the fixing structure 2115 with the other extra first accommodating portions 2117 can achieve staggered installation of the terminal connecting portion 2113 and the pole tab connecting portion 2111 in the width direction, thereby facilitating the installation of other parts in the battery cell 20.

[0118] According to some embodiments of the present application, optionally, referring to Figure 13, in some embodiments, each sub-rivet portion 21151 has a sub-protrusion and a sub-recess, each sub-protrusion protrudes in the direction of the second main surface 21139, and each sub-recess is recessed from the first main surface 21138 toward the second main surface 21139, and the sub-protrusion of one sub-rivet portion 21151 of two adjacent sub-rivet portions 21151 accommodates and is fixedly connected to the sub-recess of the other sub-rivet portion 21151.

[0119] The riveting of the sub-protrusions and sub-recesses of the adjacent layers of the sub-terminal connecting parts 21137 can be achieved through a stamping process. For example, the second-layer sub-terminal connecting part 21137 is stacked on the first-layer sub-terminal connecting part 21137 and is punched into the area where the fixed structure 2115 is to be formed. This allows the second-layer sub-terminal connecting part 21137 to be riveted to the first-layer sub-terminal connecting part 21137, and sub-protrusions and sub-recesses are formed on both the first-layer sub-terminal connecting part 21137 and the second-layer sub-terminal connecting part 21137. Then, the third-layer sub-terminal connecting part 21137 is stacked on the second-layer sub-terminal connecting part 21137 and is punched into the sub-recess of the second-layer sub-terminal connecting part 21137. , the third-layer sub-terminal connecting part 21137 can be riveted to the second-layer sub-terminal connecting part 21137, and sub-protrusions and sub-recesses can be formed on the third-layer sub-terminal connecting part 21137; then, the fourth-layer sub-terminal connecting part 21137 is stacked on the third-layer sub-terminal connecting part 21137 and is punched into the sub-recesses of the third-layer sub-terminal connecting part 21137, so that the fourth-layer sub-terminal connecting part 21137 can be riveted to the third-layer sub-terminal connecting part 21137, and sub-protrusions and sub-recesses can be formed on the fourth-layer sub-terminal connecting part 21137; by stacking and riveting in this way, the sub-terminal connecting parts 21137 of each layer can be riveted together to form a terminal connecting part 2113 with an integral structure.

[0120] Compared to punching out multiple single-layer sub-terminal connecting portions and then stacking and welding them together to form a terminal connection, riveting the sub-protrusions and sub-recesses of the sub-terminal connecting portions 21137 of adjacent layers prevents misalignment during stacking, provides precise positioning, and facilitates alignment. It also eliminates the need for welding, improving the production efficiency of the current collecting member 211. Compared to rolling the material into multiple layers and then cutting them to create a multi-layer terminal connection, riveting the sub-protrusions and sub-recesses of the sub-terminal connecting portions 21137 of adjacent layers reduces burrs.

[0121] According to some embodiments of the present application, optionally, referring to Figures 12 to 15, the riveting between the sub-terminal connecting portions 21137 of adjacent layers and the riveting between the sub-protrusions of the sub-terminal connecting portions 21137 of the outermost layer and the accommodating portion 2117 can be performed in a continuous mold.

[0122] A continuous die refers to a cold stamping die in which a press uses a strip of stamping raw material in one stamping stroke, and completes multiple stamping processes simultaneously on a pair of dies with several different workstations. Each time the die completes a stamping, the material strip moves once at a fixed distance until the product is completed. Specifically, assuming that the terminal connection part 2113 includes three layers of sub-terminal connection parts 21137, there are two workstations on the die, and each workstation corresponds to a current collecting component 211. When the riveting between the sub-protrusion of the outermost layer of the sub-terminal connection part 21137 and the accommodating part 2117 on the tab connection part 2111 is performed first, and then the sub-protrusion and sub-recess of the adjacent layer of the sub-terminal connection part 21137 are riveted, the following steps are performed simultaneously at the two workstations: the die stamps the material strips corresponding to the two workstations for the first time, and the material strips are blanked at the same time. The sub-terminal connection part 21137 serves as the first layer (outermost layer) of the sub-terminal connection part 21137, and the first layer of the sub-terminal connection part 21137 is stamped. , so that the sub-protrusion on it is riveted to the accommodating portion 2117 (groove or through hole) on the connection area 21111 of the tab connection portion 2111 pre-placed in the mold, and a sub-recess is formed on the first main surface 21138 side of the first layer sub-terminal connection portion 21137; then, the material strip is moved at a fixed distance until there is a material strip in the area corresponding to the two stations, the mold punches the material strip for the second time, and the material strip is blanked at the same time. At this time, the sub-terminal connection portion 21137 serves as the second layer sub-terminal connection portion 21137, and the second layer sub-terminal connection portion 21 137 is punched so that the sub-protrusion on it is punched into the first-layer sub-terminal connecting part 21137 from the sub-recess on the first-layer sub-terminal connecting part 21137 to form a rivet, and a sub-recess is formed on the first main surface 21138 side of the second-layer sub-terminal connecting part 21137; finally, the material strip is moved again at a fixed distance until there is a material strip again in the area corresponding to the two workstations, the mold punches the material strip for the third time, and the material strip is blanked at the same time. At this time, the sub-terminal connecting part 21137 serves as the third-layer sub-terminal connecting part 21137. The three-layer sub-terminal connection part 21137 is punched so that the sub-protrusion on it is punched into the second-layer sub-terminal connection part 21137 from the sub-recess on the second-layer sub-terminal connection part 21137 to form a rivet, and a sub-recess is formed on the first main surface 21138 side of the third-layer sub-terminal connection part 21137, so as to simultaneously realize the connection between the terminal connection part 2113 and the pole ear connection part 2111 of each of the two current collecting components 211 on the two workstations, and the riveting between the sub-terminal connection parts 21137 of adjacent layers.

[0123] The riveting between the sub-terminal connecting parts 21137 of adjacent layers and the riveting between the sub-terminal connecting parts 21137 of the outermost layer and the tab connecting part 2111 are performed in the continuous mold. The continuous mold can automatically realize stack riveting, thereby improving the positioning accuracy of the current collecting component 211, and at the same time can realize mass production, thereby improving the production efficiency of the current collecting component 211.

[0124] According to some embodiments of the present application, optionally, referring to Figures 12 to 15 , the sub-protrusions and sub-recesses of the sub-terminal connecting parts 21137 of adjacent layers are interference fit, and the sub-protrusions of the sub-terminal connecting parts 21137 of the outermost layer are interference fit with the accommodating part 2117 .

[0125] The riveting of the sub-protrusions of the outermost sub-terminal connecting portion 21137 to the receiving portion 2117 can be achieved through a stamping process. After stamping, the sub-protrusions of the outermost sub-terminal connecting portion 21137 and the receiving portion 2117 form an interference fit. This interference fit strengthens the connection between the terminal connecting portion 2113 and the tab connecting portion 2111, preventing the two from separating, thereby improving the operational stability of the current collecting component 211. The riveting of the sub-protrusions and sub-recesses of the sub-terminal connecting portion 21137 of adjacent layers can also be achieved through a stamping process. After stamping, the sub-protrusions and sub-recesses of the sub-terminal connecting portion 21137 of adjacent layers form an interference fit. This interference fit strengthens the connection between multiple layers of sub-terminal connecting portions 21137.

[0126] According to some embodiments of the present application, optionally, referring to Figures 14 and 15, a second accommodating portion 2118 is provided on the terminal connecting portion, and a second protrusion 2119 is provided on the tab connecting portion, and the second protrusion 2119 is accommodated in the second accommodating portion 2118.

[0127] When the fixing structure 2115 is arranged in the end area (first connecting section 21131) of the terminal connecting part 2113 close to the electrode terminal 216, the end area (second connecting section 21133) of the terminal connecting part 2113 close to the pole tab connecting part 2111 may also be provided with a second accommodating portion 2118. At this time, the second protrusion 2119 is accommodated in the cavity 2118, which can improve the positioning accuracy when the terminal connecting part 2113 is connected to the pole tab connecting part 2111.

[0128] Specifically, in one example, each layer of sub-terminal connecting portion 21137 is formed with a sub-accommodation portion 21181. Multiple sub-accommodation portions 21181 are aligned and connected to form a second accommodation portion 2118. The second protrusion 2119 can be accommodated within the second accommodation portion 2118. The second accommodation portion 2118 can be a through hole extending through the first main surface 21138 and the second main surface 21139, or a groove extending through the second main surface 21139 but not through the first main surface 21138. Accommodating the second protrusion 2119 in the second accommodation portion 2118 improves the positioning accuracy when connecting the terminal connecting portion 2113 to the tab connecting portion 2111, thereby improving the production efficiency of the current collecting component 2111. In another example, some of the sub-terminal connecting portions 21137 are provided with sub-accommodating portions 21181, which are aligned and connected to form a second accommodating portion 2118 together, while other terminal connecting portions 21137 may not have sub-accommodating portions 21181. In this case, the second accommodating portion 2118 is a groove that passes through the second main surface 21139 but not the first main surface 21138. Similarly, the second protrusion 2119 can also be accommodated in the second accommodating portion 2118 which is a groove.

[0129] According to some embodiments of the present application, optionally, referring to FIG. 14 and FIG. 15 , the tab connection portion 2111 is fixedly connected to the terminal connection portion 2113 via the second protrusion 2119 .

[0130] Specifically, in one example, each layer of sub-terminal connecting portion 21137 is formed with a sub-accommodation portion 21181. Multiple sub-accommodation portions 21181 are aligned and connected to form a second accommodation portion 2118. The second protrusion 2119 can be interference-fitted (fixedly connected) within the second accommodation portion 2118 through a riveting process. The second accommodation portion 2118 can be a through-hole extending through the first main surface 21138 and the second main surface 21139, or a groove extending through the second main surface 21139 but not through the first main surface 21138. Direct riveting of the second protrusion 2119 to the second accommodation portion 2118 improves the positioning accuracy when riveting the terminal connecting portion 2113 to the tab connecting portion 2111, saves welding processes, and thereby improves the production efficiency of the current collecting component 2111. In another example, some of the sub-terminal connecting portions 21137 are provided with sub-accommodating portions 21181, which are aligned and connected to form a second accommodating portion 2118 together, while other terminal connecting portions 21137 do not have sub-accommodating portions 21181. In this case, the second accommodating portion 2118 is a groove that passes through the second main surface 21139 but not the first main surface 21138. Similarly, the second protrusion 2119 can also be directly riveted to the second accommodating portion 2118.

[0131] According to some embodiments of the present application, optionally, referring to FIG. 10 , the terminal connection portion 2113 and the tab connection portion 2111 are at least partially welded together.

[0132] The second connecting section 21133 is welded to the connection area 21111 of the tab connection portion 2111. In one example, the weld mark formed between the terminal connection portion 2113 and the tab connection portion 2111 is located in an area outside the fixed structure 2115. The second connecting section 21133 is welded to the connection area 21111 outside the fixed structure 2115, that is, the non-riveted position between the terminal connection portion 2113 and the tab connection portion 2111 is welded and reinforced. On the one hand, this increases the flow area of ​​the current collecting component 211, reduces internal resistance, lowers temperature rise, and improves the safety performance of the battery cell 20 (shown in Figure 3); on the other hand, it makes the connection between the terminal connection portion 2113 and the tab connection portion 2111 more secure, making it less likely for the two to separate, thereby improving the operating stability of the current collecting component 211.

[0133] In another example, the weld mark formed between the terminal connection portion 2113 and the tab connection portion 2111 may also be located in the area where the fixing structure 2115 is located. The second connection segment 21133 is welded to the area where the fixing structure 2115 is located on the connection region 21111, that is, the riveted joint between the terminal connection portion 2113 and the tab connection portion 2111 is welded and reinforced. On the one hand, this increases the flow area of ​​the current collecting component 211, reduces internal resistance, lowers temperature rise, and improves the safety performance of the battery cell 20 (shown in FIG. 3 ); on the other hand, it makes the connection between the terminal connection portion 2113 and the tab connection portion 2111 more secure, making it less likely for the two to separate, thereby improving the operating stability of the current collecting component 211.

[0134] According to some embodiments of the present application, optionally, referring to FIG. 10 , the second connecting segment 21133 is welded to the connecting region 21111 of the tab connecting portion 2111 by at least one of ultrasonic welding, molecular diffusion welding, and laser welding.

[0135] Ultrasonic welding is a process in which an ultrasonic generator converts electric current into high-frequency electrical energy, which is then converted into mechanical motion through a transducer. Finally, the mechanical motion is transmitted to the welding head through a horn. The welding head transmits the received vibration energy to the interface between the second connecting section 21133 and the tab connection portion 2111. The vibration energy is converted into heat energy through friction. The heat energy is concentrated at the interface between the second connecting section 21133 and the tab connection portion 2111, causing the interface to melt rapidly. When a certain pressure is applied, the interface between the second connecting section 21133 and the tab connection portion 2111 is fused into one. Ultrasonic welding can compact the tab connection portion 2111 and the terminal connection portion 2113 by applying pressure, preventing the occurrence of cold welds and ensuring the firmness of the tab connection portion 2111 and the terminal connection portion 2113 after welding. At the same time, ultrasonic welding can achieve metal bonding between the tab connection portion 2111 and the terminal connection portion 2113 in a relatively short time and at a relatively low temperature.

[0136] Molecular diffusion welding is a welding method that forms a bond between the tab connection 2111 and the terminal connection 2113 by causing molecular diffusion at the interface between them under a certain temperature and pressure. Using molecular diffusion welding, if the connection area 21111 of the tab connection 2111 and the second connection section 21133 of the terminal connection 2113 are made of the same material, there is no heat-affected zone at the weld, resulting in no residual stress and no melting defects. Furthermore, molecular diffusion welding has a low welding temperature, minimal damage to the tab connection 2111 and the terminal connection 2113, high welding precision, and minimal deformation.

[0137] Laser welding uses a focused laser beam as an energy source to generate heat at the interface between the tab connection portion 2111 and the terminal connection portion 2113. Laser welding ensures the secure connection between the tab connection portion 2111 and the terminal connection portion 2113, while also providing high welding speed, a large weld depth, and minimal deformation at the weld between the tab connection portion 2111 and the terminal connection portion 2113.

[0138] According to some embodiments of the present application, optionally, referring to Figures 3, 8, and 10, the terminal connection portion 2113 is disposed in a bent manner between the tab connection portion 2111 and the electrode terminal 216. The terminal connection portion 2113 is disposed in a bent manner between the tab connection portion 2111 and the electrode terminal 216, which can reduce the height space occupied by the current collecting member 211 in the battery cell 20. On the one hand, this makes the structure of the battery cell 20 more compact. On the other hand, at the same height of the battery cell 20, more space can be freed up for the electrode sheets in the electrode assembly 25, thereby increasing the energy density of the battery cell 20.

[0139] In the second aspect, referring to FIG. 2 , the present application further provides a battery 100 , comprising a battery cell 20 according to any one of the above embodiments.

[0140] In the technical solution of the embodiment of the present application, referring to Figures 3 and 10 , the battery 100 utilizes the battery cell 20 of the embodiment of the first aspect. In the top cover assembly 21 of the battery cell 20, the multi-layer sub-terminal connecting portion 21137 of the current collecting member 211 has a stronger bending ability and is less likely to break, thereby ensuring the operational stability of the battery 100. Furthermore, while maintaining the same bending ability, the overall thickness of the multi-layer sub-terminal connecting portion 21137 can be made thicker, increasing the flow area of ​​the current collecting member 211, reducing internal resistance, and lowering temperature rise, thereby improving the safety of the battery 100. Furthermore, the greater degree of bending of the multi-layer sub-terminal connecting portion 21137 also reduces the height space occupied by the current collecting member 211, thereby increasing the energy density of the battery cell 20, and thereby also increasing the energy density of the battery 100.

[0141] In the third aspect, please refer to FIG1 , the present application further provides an electrical device, which includes a battery 100 according to any one of the above embodiments, and the battery 100 is used to provide electrical energy.

[0142] In the technical solution of the embodiment of the present application, referring to Figures 3 and 10 , an electrical device utilizes the battery 100 of the embodiment of the second aspect. In the battery cells 20 of this battery 100, the multi-layer sub-terminal connecting portion 21137 of the current collecting member 211 in the top cover assembly 21 has a stronger bending ability and is less prone to breakage, thereby ensuring the operational stability of the electrical device. Furthermore, while maintaining the same bending ability, the overall thickness of the multi-layer sub-terminal connecting portion 21137 can be made thicker, thereby increasing the flow area of ​​the current collecting member 211, reducing internal resistance, and lowering temperature rise, thereby improving the safety of the battery 100. Furthermore, the greater degree of bending of the multi-layer sub-terminal connecting portion 21137 also reduces the height space occupied by the current collecting member 211, thereby increasing the energy density of the battery cells 20, thereby also increasing the energy density of the battery 100, and thus increasing the battery life of the electrical device.

[0143] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: Electrode assembly, including tabs; a housing for accommodating the electrode assembly; an electrode terminal, disposed on the housing; and The current collecting component includes a tab connection part and a terminal connection part, wherein the tab connection part is used to connect the tab, and the terminal connection part is used to connect the electrode terminal. The terminal connection part includes a plurality of sub-terminal connection parts stacked together, and each layer of the sub-terminal connection part includes a sub-rivet part, and any two adjacent sub-rivet parts are riveted and fixed.

2. The battery cell according to claim 1, wherein: Any two adjacent sub-riveting parts are connected by welding.

3. The battery cell according to claim 1 or 2, characterized in that: The terminal connecting portion is provided with a fixing structure, in which all the sub-riveting portions are stacked in sequence and cooperate with each other.

4. The battery cell according to claim 3, characterized in that The fixing structure is provided at an end region of the terminal connecting portion close to the electrode terminal, and / or at an end region of the terminal connecting portion close to the tab connecting portion.

5. The battery cell according to claim 3 or 4, characterized in that: The number of the fixing structures is one or more.

6. The battery cell according to any one of claims 3 to 5, characterized in that: The terminal connecting portion has a first main surface and a second main surface opposite to each other along its thickness direction after being unfolded. The fixing structure has a concave portion formed on one side of the first main surface and a first convex portion formed on the second main surface.

7. The battery cell according to claim 6, characterized in that The tab connection portion is provided on a side of the terminal connection portion close to the second main surface. The tab connection portion is provided with a first accommodation portion, and the first protrusion is accommodated in the first accommodation portion.

8. The battery cell according to claim 7, characterized in that The terminal connecting portion is fixedly connected to the tab connecting portion through the first protrusion.

9. The battery cell according to claim 7 or 8, characterized in that: Each of the sub-rivet portions has a sub-protrusion and a sub-recess, each of the sub-protrusions protrudes toward the second main surface, and each of the sub-recesses is recessed from the first main surface toward the second main surface, and the sub-protrusion of one of the two adjacent sub-rivet portions is accommodated and fixedly connected to the sub-recess of the other sub-rivet portion.

10. The battery cell according to any one of claims 1 to 9, characterized in that: The terminal connecting portion is provided with a second accommodating portion, the tab connecting portion is provided with a second convex portion, and the second convex portion is accommodated in the second accommodating portion.

11. The battery cell according to claim 10, characterized in that The tab connection portion is fixedly connected to the terminal connection portion through the second protrusion.

12. The battery cell according to any one of claims 1 to 11, characterized in that: The terminal connection portion and the tab connection portion are at least partially welded.

13. The battery cell according to claim 12, characterized in that: The weld mark formed between the terminal connecting portion and the tab connecting portion is located in a region outside the fixing structure.

14. The battery cell according to any one of claims 1 to 13, characterized in that: The terminal connecting portion is disposed in a bent manner between the tab connecting portion and the electrode terminal.

15. A battery, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 14.

16. An electrical device, characterized in that: The electrical device comprises the battery according to claim 15, and the battery is used to provide electrical energy.

Images