Battery cell, battery and electrical device

Abstract

Battery cell (100), comprising: a housing (1) wherein an opening (11) is provided at an end section of the housing (1); an electrode arrangement (2) arranged inside the housing (1), wherein the electrode arrangement (2) comprises an electrode body (21) and a first tab (22), the first tab (22) extending from an end of the electrode body (21); an end cap (3) that closes the opening (11), the outer circumference of the end cap (3) being attached to the housing (1) by welding; and a conductive component (4) arranged between the electrode arrangement (2) and the end cap (3), wherein the conductive component (4) is electrically connected to the first tab (22), wherein the conductive component (4) is electrically connected to at least one of the end cap (3) and the housing (1), and wherein an outer edge of the conductive component (4) extends at a position near a welding area.

Description

TECHNICAL AREA

[0001] The present disclosure relates to the technical field of batteries, in particular a battery cell, a battery and a power-consuming device. STATE OF THE ART

[0002] Thanks to their advantages such as high energy density, high power density, numerous charging cycles and long storage time, batteries like lithium-ion batteries are widely used in electric vehicles.

[0003] However, improving the performance and safety of batteries in electric vehicles currently in use has always been a problem for the industry. REVELATION OF THE INVENTION

[0004] One purpose of the present disclosure is to improve the performance and safety of batteries currently in use.

[0005] According to a first aspect of the present disclosure, a battery cell is specified which comprises the following: a housing, wherein an opening is provided at one end section of the housing; an electrode arrangement which is arranged inside the housing and comprises an electrode body and a first tab, wherein the first tab extends out from one end of the electrode body; an end cap that closes the opening, the outer circumference of the end cap being attached to the housing by welding; and a conductive component located between the electrode assembly and the end cap, wherein the conductive component is electrically connected to the first tab, wherein the conductive component is electrically connected to at least one of the end cap and the housing, and wherein an outer edge of the conductive component extends at a position near a welding area.

[0006] In this embodiment, the outer edge of the conductive component extends between the end cap and the housing near the welding area. This allows the conductive component to be fusion-welded to at least one of the end cap and the housing by the heat generated when welding the end cap to the housing opening. After cooling and solidification, a single-piece connection interface is formed, resulting in the conductive component being electrically connected to at least one of the end cap and the housing, forming a conductive loop. This eliminates the need for an additional welding step to the end cap, thus simplifying the process.Compared to welding the end cap and the conductive component from the outside, the residual heat generated during the welding of the end cap and the housing is indirectly used for fusion welding the conductive component, thus reducing energy consumption during welding. Even if the conductive component and the end cap or housing are made of different metal materials, no obvious molten metal is visible on a contact surface between the conductive component and the end cap or housing. Instead, the atoms of an upper metal layer dissolve into one another at high temperatures, forming a conductive cross-section. This process is similar to laser heat conduction welding and can reduce microcracks to prevent electrolyte leakage, thereby improving the performance and safety of the battery cell during use.

[0007] In some embodiments, it is provided that the distance between the outer edge of the conductive component and the welding area is no more than 15 mm.

[0008] In this embodiment, the outer edge of the conductive component is located a short distance from the welding area, making it possible to reliably fusion weld the conductive component to at least one of the end cap and the housing by utilizing the heat generated during welding, in order to electrically connect the conductive component to at least one of the end cap and the housing and reliably form a conductive loop, thereby improving the electrical conductivity of the battery cell.

[0009] In some embodiments, the first tab is a negative tab.

[0010] Since the negative tab and the end cap are made of different materials in this embodiment, cracks can form on the surface of the end cap when it is welded from the outside. The residual heat generated during the welding of the end cap and the housing is indirectly used to fusion weld the conductive component, thus reducing energy consumption during welding. Even if the conductive component and the end cap or housing are made of different metals, less molten metal forms at the contact surface between the conductive component and the end cap or housing. Instead, the atoms of an upper metal layer dissolve into one another at high temperatures, forming a conductive cross-section. This reduces microcracks, preventing electrolyte leakage and thus improving the performance and safety of the battery cell during use.

[0011] In some embodiments, the outer edge of the conductive component and the end cap are designed to form a recess-projection fitting system.

[0012] In this embodiment, the outer edge of the conductive component and the end cap form the recess-projection fitting system, which positions the conductive component and holds it in a suitable position during welding of the end cap and housing, thus ensuring reliable welding. Furthermore, it is possible to increase the number of weld interfaces between the conductive component and the end cap or housing. These multiple weld interfaces are located near the welding area between the end cap and the housing, thereby improving the reliability of the electrical connection between the conductive component and the end cap or housing.

[0013] In some embodiments, the conductive component is provided to include the following: a main body section that is electrically connected to the first tab; and a folded section that is connected to an edge of the main body section and extends towards the end cap; wherein a recess is provided in an area of ​​an inner surface of the end cap which is located near the edge, and wherein the folded section extends into the recess.

[0014] Since this embodiment includes a recess in the end cap, the local thickness of the end cap can be reduced to such an extent that the folded section can be positioned closer to the welding area between the end cap and the housing. Thus, with a given welding power, sufficient residual heat can be ensured when welding the end cap and the housing. This heat improves the welding of the conductive component to the end cap or housing, guaranteeing the reliability of the electrical connection and thereby improving the performance of the battery cell. Alternatively, the welding power required to join the end cap and the housing can be reduced while maintaining the welding effect of the conductive component.

[0015] In some embodiments, an end section of the folded section is in contact with a bottom wall of the recess.

[0016] In this embodiment, the end section of the folded section is in contact with the bottom wall of the recess, and the interface for joining is located closest to the welding area between the end cap and the housing, thereby fully utilizing the residual heat generated during welding, improving the welding of the folded section and the bottom wall, and guaranteeing the reliability of the electrical connection, thus improving the performance of the battery cell.

[0017] In some embodiments, a guide section is provided at an opening of the recess and configured to insert the folded section into the recess.

[0018] In this embodiment, the guide section is provided at the opening of the recess, allowing the folded section to be smoothly installed in the recess, thus reducing the requirements for the accuracy of fit between the folded section and the recess, facilitating the assembly of the end cap, preventing deformation of the conductive component during assembly, and increasing assembly efficiency.

[0019] In some embodiments, the end surface of the main body section facing away from the first tab is in contact with the inner surface of the end cap.

[0020] In this embodiment, the contact area between the conductive component and the end cap can be enlarged, while the electrical connection is established by locally welding the conductive component and the end cap or the housing, thereby improving the reliability of the electrical connection between the conductive component and the end cap and thus the performance of the battery cell.

[0021] In some embodiments, one end of the housing protrudes outwards as a whole near the end cap to form a step on an inner side wall of the housing, with the main body section resting against the step.

[0022] Since, in this embodiment, the main body section rests against the step, an edge region of the main body section can be stably supported, and the conductive component is more stable after assembly. This allows the conductive component to be reliably welded by utilizing the residual heat generated during the welding of the end cap and the housing. Furthermore, this prevents the main body section from deforming in any direction relative to the electrode assembly, thus avoiding damage to the electrode plates in the electrode body or to the first tab due to deformation of the main body section and ensuring the operating performance of the battery cell.Based on such a design, a gap between the housing and the electrode assembly can also be arranged offset from a connection surface between the housing and the end cap in order to reduce the risk of electrolyte leakage at the connection surface between the housing and the end cap.

[0023] In some embodiments, the folded section is provided to extend along the entire circumference of the main body section.

[0024] In this embodiment, the folded section extends along the entire circumference of the main body section, thereby increasing the overall structural strength of the conductive component to prevent deformation. Furthermore, the folded section can be welded to its entire circumference using the residual heat generated during the welding of the end cap and housing. This improves the reliability of the electrical connection between the conductive component and the housing or end cap, ensuring reliable operation of the battery cell. Additionally, the flow capacity of the conductive component can also be improved.

[0025] In some embodiments, the folded section comprises several folded subsections, wherein the several folded subsections are spaced apart from each other along the circumference of the main body section.

[0026] In this embodiment, the folded section is provided which is divided into several spaced-apart folded sub-sections, thereby facilitating the folding process, achieving better manufacturability, avoiding overlap between adjacent folded sub-sections, realizing smooth assembly even with small clearance between the recess and the folded section, and ensuring a uniform thickness of the folded sub-sections, thus facilitating welding by utilizing the residual heat generated during welding of the end cap and the housing.

[0027] In some embodiments, the conductive component has a sheet metal structure, wherein the folded section and the main body section are formed in one piece, and wherein a weakened section is provided in a connection area between the folded section and the main body section.

[0028] In this embodiment, the weakened section is provided to facilitate bending of the folded section, to reduce the external force to be exerted during bending, to decrease the deformation of the main body section, and to improve the reliability of the electrical connections between the main body section and the first tab, as well as between the folded section and the end cap or housing.

[0029] In some embodiments, the recess is provided in the outer side wall of the end cap.

[0030] In this embodiment, the recess is easy to machine, which reduces the requirements for the precise fit between the recess and the folded section, thus simplifying assembly. Furthermore, the contour dimension of the end cap, for example, the radial dimension of a cylindrical battery cell, can be minimized using the recess, thereby reducing the overall size of the battery cell.

[0031] To improve the effectiveness of the electrical connection, the interface between the end section of the folded section and the recess can be positioned closer to the weld area between the housing and the recess. This facilitates welding the folded section by utilizing the residual heat generated during the welding of the end cap and the housing. Secondly, the outer side wall of the folded section can be positioned closer to the inner side wall of the housing. This helps to create a weld interface between the outer side wall of the folded section and the inner side wall of the housing, again utilizing the residual heat generated during welding to establish the electrical connection between the conductive component and the housing.Thirdly, when welding the end cap and housing, a small amount of solder flux can flow into the gap between the folded section and the end cap or housing, further improving the reliability of the conductive component during welding. All of the above advantages can lead to better reliability of the electrical connection of the conductive component, thereby improving the electrical conductivity of the battery cell.

[0032] In some embodiments, the outer side wall of the folded section is in contact with the inner side wall of the housing.

[0033] In this embodiment, a welding interface is formed between the outer side wall of the folded section and the inner side wall of the housing, and when the housing is welded to the end cap, the residual heat generated during welding is used to weld the folded section to the housing in order to establish the electrical connection between the folded section and the housing, thus creating a reliable current flow from the first tab to the housing, thereby improving the electrical conductivity of the battery cell.

[0034] In some embodiments, the recess is located in an area of ​​the inner surface of the end cap that is near the edge, an inner wall of the recess comprises a first inner side wall and a first outer side wall, and the folded section extends into the recess and is in contact with at least a part of the inner wall of the recess.

[0035] In this embodiment, the recess is located near the edge of the end cap, so that the mating surfaces between the recess, the end cap, and the housing are offset. This prevents the soldering flux from penetrating the recess during welding of the end cap and housing. Furthermore, the welding of the conductive component and the end cap is achieved solely by utilizing the residual heat generated during the welding process. In particular, the welding of the folded section and the recess is also achieved by utilizing this residual heat. Since the conductive component and the end cap are made of different metals—for example, the conductive part is made of copper and the end cap of steel—it is possible to prevent molten copper or a copper alloy from penetrating a grain boundary in the steel within a weld zone.Furthermore, cracks in the end cap can be avoided, thus solving the problem of outward penetration of the electrolyte from the battery cell after prolonged use and ensuring the performance and operational safety of the battery cell.

[0036] In some embodiments, the folded section is provided to have a second inner side wall and a second outer side wall, wherein the second inner side wall is in contact with the first inner side wall and / or the second outer side wall is in contact with the first outer side wall.

[0037] In this embodiment, the respective inner and / or outer side walls of the folded section and the recess are in contact, allowing the conductive component to be positioned in such a way as to improve its stability during assembly. Furthermore, the folded section and the recess can be welded together more effectively by utilizing the residual heat generated during the welding of the end cap and the housing. Additionally, the contact between the side walls creates an interface between the folded section and the recess, enabling reliable welding. This improves the reliability of the electrical connection between the conductive component and the end cap, and consequently, the electrical conductivity of the battery cell.

[0038] In some embodiments, the battery cell is cylindrical, wherein the main body section is circular and has a diameter of d, where 10 mm ≤ d ≤ 100 mm, and wherein the folded section has an extent of D, where 0.2 mm ≤ D ≤ 1 mm.

[0039] In some embodiments, the recess has a depth of H1, where 0.1 mm ≤ H1 ≤ 1.8 mm and 0 ≤ |L + D + H-H1-h| ≤ 0.2 mm, where H is the thickness of the end cap, L is the thickness of the conductive component, D is the extent of the folded section, and h is the distance between the step and an outer end face of the housing, wherein the step on the inner side wall of the housing is formed by the end of the housing projecting outwards as a whole near the end cap.

[0040] In some embodiments, the end cap is circular and has a diameter of C1, and the bottom wall of the recess has a width of C2, where 10 mm ≤ C1 ≤ 100 mm and 0.2 mm ≤ C2 ≤ 2 mm.

[0041] In some embodiments, the end of the housing projects outwards as a whole near the end cap to form a step on an inner side wall of the housing, and the main body section rests against the step; wherein the step has a width of W, and wherein the distance between the step and the outer end face of the housing is h, where 0.2 mm ≤ W ≤ 1.0 mm and 1 mm ≤ h ≤ 10 mm.

[0042] In some embodiments, the end of the housing projects outwards as a whole near the end cap to form a step on an inner side wall of the housing, and the main body section rests against the step; wherein the step has a width of W, and wherein the distance between the step and the outer end face of the housing is h, where 0.2 mm ≤ W ≤ 5.0 mm and 1 mm ≤ h ≤ 10 mm.

[0043] In some embodiments, the conductive component is provided to have a thickness of L, where 0.2 mm ≤ L ≤ 1.0 mm; and the end cap is provided to have a thickness of H, where 0.2 mm ≤ H ≤ 2.0 mm; and / or the electrode body is cylindrical and has a diameter of P, where 5 mm ≤ P ≤ 97 mm.

[0044] According to a second aspect of the present disclosure, a battery is provided comprising: a housing arrangement and a battery cell according to the foregoing embodiments, wherein the battery cell is arranged within the housing arrangement.

[0045] According to a third aspect of the present disclosure, a power-consuming device is provided which includes the battery according to the embodiment described above. The battery serves to supply the power-consuming device with electrical energy.

[0046] According to a fourth, unclaimed aspect of the present disclosure, a method for manufacturing a battery cell is provided, the method comprising the following: a step for providing components in which a housing, an end cap, an electrode assembly and a conductive component are provided, wherein an opening is provided at an end section of the housing, and wherein the electrode assembly comprises an electrode body and a first tab, the first tab being extended from an end of the electrode body; a step for attaching the electrode, in which the electrode assembly is mounted in the housing and the conductive component is electrically connected to the first tab; and a step for attaching the end cap, wherein the opening is closed by the end cap to allow the conductive component to be located between the electrode assembly and the end cap, wherein the outer circumference of the end cap is attached to the housing by welding, wherein the welded conductive component is electrically connected to at least one of the end cap and the housing, and wherein an outer edge of the conductive component extends at a position near a weld area.

[0047] In this embodiment, the outer edge of the conductive component extends between the end cap and the housing near the welding area. This allows the conductive component to be fusion-welded to at least one of the end cap and the housing by the heat generated when welding the end cap to the housing opening. After cooling and solidification, a single-piece connection interface is formed, resulting in the conductive component being electrically connected to at least one of the end cap and the housing, forming a conductive loop. This eliminates the need for an additional welding step to the end cap, thus simplifying the process.Compared to welding the end cap and the conductive component from the outside, the residual heat generated during the welding of the end cap and the housing is indirectly used for fusion welding the conductive component, thus reducing energy consumption during welding. Even if the conductive component and the end cap or housing are made of different metal materials, no obvious molten metal is visible on a contact surface between the conductive component and the end cap or housing. Instead, the atoms of an upper metal layer dissolve into one another at high temperatures, forming a conductive cross-section. This process is similar to laser heat conduction welding and can reduce microcracks to prevent electrolyte leakage, thereby improving the performance and safety of the battery cell during use.

[0048] In some embodiments, the conductive component comprises a main body section and a folded section, wherein the main body section is configured to be electrically connected to the first tab, while the folded section is connected to an edge of the main body section, the main body section and the folded section lying in the same plane prior to assembly. Furthermore, the manufacturing method comprises the following:

[0049] Bending the folded section towards the main body section and forming an obtuse angle between the folded section and the main body section, so that the conductive component sits firmly against an inner wall of the housing when installed inside the housing.

[0050] In this embodiment, the folded section is bent away from the main body section during assembly so that an obtuse angle is formed between them, whereby when the conductive component is installed in the housing, the folded section can be pressed against the inner wall of the housing, so that the folded section can lie firmly against the inner wall of the housing, thereby improving the reliability of the electrical connection between the conductive component and the housing and thus the electrical conductivity of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the accompanying drawings required in the embodiments of the present disclosure are briefly described below. Obviously, the accompanying drawings described below represent only some embodiments of the present disclosure, and a person skilled in the art can derive further accompanying drawings from these without any creative effort. Fig. Figure 1 shows a schematic structural view of a battery installed in a vehicle according to some embodiments of the present disclosure. Fig. Figure 2 shows an exploded view of a battery according to some embodiments of the present disclosure. Fig. Figure 3 shows a front view of a battery cell according to a first embodiment of the present disclosure. Fig. 4 is a cross-sectional view along line AA of the in Fig. 3 battery cells shown. Fig. Figure 5 shows an enlarged view of section B from Fig. 4. Fig. Figure 6 shows a schematic structural view of a guide section that is designed for a recess in the Fig. The battery cell shown in section 4 is provided for. Fig. Figure 7 shows a schematic structural view of a step attached to a housing of the in Fig. The battery cell shown in section 4 is provided for. Fig. Figure 8 shows a front view of a conductive component before bending according to the first embodiment. Fig. Figure 9 shows a cross-sectional view of the conductive component before bending. Fig. Figure 10 shows an enlarged view of section C from Fig. 9. Fig. Figure 11 shows a cross-sectional view of a conductive component according to the first embodiment, which has been bent. Fig. Figure 12 shows an enlarged view of section D from Fig. 11. Fig. Figure 13 shows a side view of an end cap according to the first embodiment of the present disclosure. Fig. Figure 14 shows a cross-sectional view of a battery cell according to a second embodiment of the present disclosure. Fig. Figure 15 shows an enlarged view of section E from Fig. 14. Fig. Figure 16 shows a schematic structural view of a recess located in a Fig. The end cap shown in section 14 is provided. Fig. Figure 17 shows in a flowchart an unclaimed method for manufacturing a battery cell according to some examples of the present disclosure.

[0052] The attached drawings are not drawn to scale. Reference symbol list:

[0053] 100. Battery cell; 1. Housing; 11. Opening; 12. Stage; 13. Mounting hole; 2. Electrode assembly; 21. Electrode body; 22. First tab; 23. Second tab; 3. End cap; 3A. First section; 3B. Second section; 31. Recess; 311. First inner side wall; 312. First outer side wall; 313. Bottom wall; 314. Guide section; 4. Conductive component; 41. Main body section; 42. Folded section; 42'. Folded subsection; 421. Second inner side wall; 422. Second outer side wall; 43. Weakened section; 5. Electrode terminal; 200. Battery; 201. Housing assembly; 201A. Housing body; 201B. Cover; 300. Vehicle; 301. Axle; 302. Wheel; 303. Engine; 304. Control unit. DETAILED DESCRIPTION OF THE EXECUTION FORMS

[0054] The embodiments of this disclosure are described in more detail below with reference to the accompanying drawings and embodiments. The following detailed description of the embodiments and the accompanying drawings serves to illustrate the principle of this disclosure by means of examples and is not intended to limit the scope of this disclosure. That is to say, this disclosure is not limited to the embodiments described.

[0055] In the description of the embodiments of this disclosure, the term "several" means two or more than two (including two). Likewise, the term "several group" means two or more than two groups (including two groups), and the term "several pieces" means two or more than two pieces (including two pieces).

[0056] In this disclosure, the terms "above", "below", "top", "bottom", "front", "back", "inside", "outside", etc. are used as orientation or position indicators that serve only to facilitate the description of this disclosure and do not indicate or imply that the device referred to must have a particular orientation or be designed and operated in a particular orientation. Therefore, these terms are not to be understood as limiting the present disclosure.

[0057] The terms "first," "second," "third," etc., are used for descriptive purposes only and are not to be understood as an implicit or explicit indication of relative significance. The term "perpendicular" should not be understood in a strict sense, but rather as perpendicular within a certain tolerance range. The term "parallel" should not be understood in a strict sense, but rather as parallel within a certain tolerance range. The orientation specifications in the following description all refer to the directions shown in the accompanying drawings and do not limit the specific structure in the present disclosure.

[0058] Furthermore, it should be noted that, in the description of this disclosure, the terms "attach," "connect," and "join" are to be understood in a broad sense unless expressly stated and defined otherwise. Thus, the connection may, for example, be a permanent, detachable, or one-piece connection. Moreover, both direct connections and indirect connections, or connections made via an intermediate piece, are conceivable. For the person skilled in the art, the specific meanings of the terms mentioned above in this disclosure must be interpreted according to the specific circumstances.

[0059] The term “an embodiment” used here means that the specific features, structures, and properties described in connection with the embodiment may be included in at least some embodiments of the present disclosure. The use of this term at different points in the description does not necessarily refer to the same embodiment or to an independent or alternative embodiment that excludes another embodiment. A person skilled in the art may understand, either explicitly or implicitly, that the embodiment described here can be combined with another embodiment.

[0060] A battery cell can comprise a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium / lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., without being limited to the embodiments described in the present disclosure. The battery cell can be cylindrical, flat, cuboid, or have another shape, again without being limited to the embodiments described in the present disclosure. Generally, battery cells are divided into three types according to their packaging: cylindrical battery cells, prismatic battery cells, and pouch battery cells, again without being limited to the embodiments described in the present disclosure.

[0061] A typical battery cell generally comprises a casing and an electrode assembly housed within the casing, the interior of which is filled with an electrolyte. The electrode assembly is primarily formed by stacking or winding a first and a second battery cell with opposite polarities, typically with a battery separator between the first and second cells. The coated portions of the first and second cells form a main body section of the electrode assembly, while the uncoated portions of the first and second cells each form a first tab and a second tab, respectively.In a lithium-ion battery, the first battery cell can be a positive battery cell comprising a positive current collector and positive coatings arranged on two sides of the positive current collector, the material of which can be, for example, aluminum, and the positive coatings can consist of, for example, lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganate, etc.; the second battery cell, on the other hand, can be a negative battery cell comprising a negative current collector and negative coatings arranged on two sides of the negative current collector, the material of which can be, for example, copper, and the negative coatings can consist of, for example, graphite or silicon, etc.The first and second tabs can be located together at one end of the main body section or at opposite ends of the main body section. During charging and discharging of the battery, the positive and negative coatings react with the electrolyte, with the tabs connecting to the electrode terminals to form a current loop.

[0062] Existing batteries suffer from a lack of safety after prolonged use. The inventor's research has shown that, in a cylindrical battery, a positive tab is connected to an electrode terminal and a negative tab to a housing. A conductive section is generally created on the negative tab by flattening or smoothing it after cutting. A current collector and the conductive section are then laser-welded. After the electrode assembly is inserted into the housing, a cover is welded and sealed to the housing. Finally, the cover is welded to the outside of the current collector, creating a conductive path from the negative tab, through the current collector and the cover, to the housing.

[0063] Generally, the negative terminal and the current collector disc are made of copper, while the cover is made of steel. If the cover is welded to the current collector disc using laser transmission welding, the weld interface between the steel and copper is susceptible to microcracking. There are two types of microcracks, which mainly occur in the weld zone and the heat-affected zone. After prolonged use, the battery is subject to electrolyte permeation, leading to reduced performance and a safety risk.

[0064] Cracks in the weld area are mainly caused by the following factors: 1. The coefficient of thermal expansion and thermal conductivity of steel differ significantly from those of copper. Copper's coefficient of thermal expansion is approximately 40% higher than that of iron, so the weld is subjected to high stress during cooling and solidification, leading to cracks in the weld. 2. Due to excessive laser power during welding the end cap and the conductive component, a molten channel forms in the end cap, and liquid copper or copper alloys have a strong permeation effect on a grain boundary in the steel near the weld zone.During crystallization, the microstructure of the metal exhibits defects, and microcracks can form on the surface of the steel, with breakthrough cracks forming in the heat-affected zone under the influence of tensile stress during welding.

[0065] By analyzing the causes of the defects, the inventor is convinced that cracks can be reduced by eliminating the need to weld the lid and current collector from the outside. This improves the reliability of the electrical connection between the current collector and the lid. Consequently, the problem of electrolyte leakage through microcracks in the battery during use can be solved, thus improving the battery's performance and safety.

[0066] Based on this improvement idea, the present disclosure aims to provide a battery cell comprising a housing, an electrode assembly, an end cap, and a conductive component. An opening is provided at one end section of the housing. The electrode assembly is located within the housing and comprises an electrode body and a first tab, the first tab extending from one end of the electrode body. The end cap closes the opening, the outer circumference of which is welded to the housing. The conductive component is located between the electrode assembly and the end cap and is electrically connected to the first tab. The conductive component is electrically connected to at least one of the end cap and the housing, and an outer edge of the conductive component extends to a position near a weld area.

[0067] The battery cell in the embodiments of the present disclosure is applicable to a battery and a power-consuming device that uses the battery.

[0068] The power-consuming device can be, for example, a mobile phone, a portable device, a laptop, an electric motorcycle, an electric vehicle, a ship, a spacecraft, an electric toy, or a power tool. For example, a spacecraft includes an airplane, a rocket, a space shuttle, or a spaceship. Electric toys include stationary or mobile electric toys, such as a game console, an electric toy car, an electric toy ship, or an electric toy airplane. Power tools include metal-cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an electric impact drill, a concrete vibrator, and an electric planer.

[0069] As in Fig. As shown in Figure 1, the power-consuming device can be a vehicle 300, for example, an environmentally friendly vehicle. The environmentally friendly vehicle can be a battery-powered electric vehicle, a hybrid electric vehicle, an extended-range electric vehicle, or the like. Alternatively, the power-consuming device can also be an unmanned aerial vehicle, a ship, or the like. In particular, the vehicle 300 can comprise an axle 301, wheels 302 connected to the axle 301, a motor 303, a control unit 304, and a battery 200, wherein the motor 303 is configured to rotate the axle 301, the control unit 304 is configured to control the operation of the motor 303, and the battery 200 can be located at the bottom, front, or rear of the vehicle 300 and can be configured to supply electrical energy for the operation of the motor 303 and other components in the vehicle.

[0070] As in Fig. As shown in Figure 2, the battery 200 comprises a housing assembly 201 and battery cells 100. The battery 200 can contain one or more battery cells 100. If multiple battery cells 100 are provided, these battery cells 100 can be connected in series, parallel, or in a series-parallel configuration, where the series-parallel configuration means that the multiple battery cells 100 are connected both in series and in parallel. It is possible that the multiple battery cells 100 are first connected in series, parallel, or in a series-parallel configuration to form a battery module, and then multiple battery modules are connected in series, parallel, or in a series-parallel configuration, which are accommodated in the housing assembly 201 to form a unit.It is also possible for all battery cells 100 to be connected directly in series, parallel, or in a series-parallel configuration, and then a unit consisting of all battery cells 100 is accommodated in the housing arrangement 201. The battery cells 100 can each be cylindrical or cuboid in shape.

[0071] The housing assembly 201 has a hollow internal structure. For example, the housing assembly 201 can comprise a housing body 201A and a cover body 201B. The housing body 201A and the cover body 201B are joined together. For example, the housing body 201A and the cover body 201B can each be a hollow cuboid with an opening on only one side, wherein the opening of the housing body 201A and the opening of the cover body 201B are arranged opposite each other, and wherein the housing body 201A and the cover body 201B are fitted together to form a housing with a closed cavity.It is also possible that the housing body 201A is a cuboid with an opening and the cover body 201B is plate-shaped, or that the cover body 201B is a cuboid with an opening and the housing body 201A is plate-shaped, wherein the housing body 201A and the cover body 201B are arranged opposite each other and joined together to form the housing assembly 201 with a closed cavity. At least one of the several battery cells 100 is connected in parallel, in series, or in a series-parallel configuration and is located in the closed cavity formed by the fit between the housing body 201A and the cover body 201B.

[0072] The battery cell 100 can, for example, include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium / lithium-ion battery, or a magnesium-ion battery, etc.

[0073] In some embodiments, they show Fig. 3 and Fig. Figure 4 shows a schematic structural view of a cylindrical battery cell 100. The battery cell 100 comprises a housing 1, an electrode assembly 2, an end cap 3, and a conductive component 4. An opening 11 is provided at one end section of the housing 1. The electrode assembly 2 is arranged inside the housing 1 and comprises an electrode body 21 and a first tab 22, which extends from one end of the electrode body 21. The end cap 3 closes the opening 11, and the outer circumference of the end cap 3 is attached to the housing 1 by welding.The conductive component 4 is located between the electrode arrangement 2 and the end cap 3, wherein the conductive component 4 is electrically connected to the first tab 22, wherein the conductive component 4 is electrically connected to at least one of the end cap 3 and the housing 1, and wherein an outer edge of the conductive component 4 extends at a position near a welding area.

[0074] The housing 1 is hollow to accommodate the electrode assembly 2. The housing 1 has an opening 11, and the end cap 3 serves to close the opening 11. In the case of a cuboid battery cell 100, the housing 1 is cuboid, and the end cap 3 is a rectangular plate. In the case of a cylindrical battery cell 100, the end cap 3 is disc-shaped. The housing 1 can be provided with the opening 11 at only one end and with a mounting hole 13 at the other end, with an electrode connection 5 provided at the mounting hole 13. Alternatively, the housing 1 can be provided with an opening 11 at each end, with both openings 11 being closed by end caps 3, and with an electrode connection 5 being provided at one of the end caps 3.

[0075] The electrode assembly 2 comprises an electrode body 21, a first tab 22, and a second tab 23, wherein the first tab 22 and the second tab each extend from two ends of the electrode body 21. Optionally, the first tab 22 can be a negative tab and the second tab 23 a positive tab. Alternatively, the first tab 22 can be a positive tab and the second tab 23 a negative tab. For example, the positive tab can be made of aluminum and the negative tab of copper. The first tab 22 can be electrically connected to the end cap 3 via the conductive component 4. The second tab 23 can be electrically connected directly to the electrode terminal 5 or electrically connected to the electrode terminal 5 via the conductive component.For example, the electrical connections between the first tab 22 and the conductive component 4, as well as between the second tab 23 and the electrode connection 5 or the conductive component, can be made by laser welding.

[0076] The outer circumference of the end cap 3 is attached to the housing 1 by welding, for example, by laser welding. The conductive component 4 can be made of a metallic material. The outer edge of the conductive component 4 extends at a position near the welding area such that it is possible to weld a section of the conductive component 4 located near the edge to the end cap 3 and / or the housing 1 by utilizing the heat generated during the welding of the end cap 3 and the housing 1, thus enabling the conductive component 4 to be electrically connected to at least one of the end cap 3 and the housing 1. For example, both the end cap 3 and the housing 1 can be made of steel.

[0077] If the conductive component 4 is electrically connected to the end cap 3 using the heat generated during the welding of the end cap 3 and the housing 1, a conductive path is created from the first tab 22 via the conductive component 4 and the end cap 3 to the housing 1. Optionally, if the conductive component 4 is electrically connected to the housing 1, current can also be conducted between the conductive component 4 and the end cap 3 through contact between these two elements.If the conductive component 4 is electrically connected to both the end cap 3 and the housing 1, two conductive paths can be realized simultaneously, resulting in more reliable electrical conductivity. In the battery cell 100 in this embodiment, the housing 1 serves as an additional electrode terminal with the opposite polarity to the electrode terminal 5, in order to establish an electrical connection to the outside.

[0078] An assembly process for the battery cell 100 comprises: flattening the first tab 22 of the electrode assembly 2 or smoothing the first tab after cutting the tab to form a conductive section, and welding the conductive section to the conductive component 4 using a laser; installing the electrode assembly into the housing 1 and welding the electrode connection 5 to the second tab 23 using a laser from outside the housing 1; and attaching the end cap 3 to the opening 11 of the housing 1, welding the outer circumference of the end cap 3 to an inner wall of the housing 1 using a laser for sealing, and electrically connecting the outer edge of the conductive component 4 to at least one of the end cap 3 and the housing 1 using the heat generated during laser welding.

[0079] In this embodiment, the outer edge of the conductive component 4 extends near the welding area between the end cap 3 and the housing 1. This allows the conductive component 4 to be fusion-welded to at least one of the end cap 3 and the housing 1 by the heat generated when the end cap 3 is welded to the opening 11 of the housing 1. After cooling and solidification, a single-piece connection interface is formed, so that the conductive component 4 is electrically connected to at least one of the end cap 3 and the housing 1, forming a conductive loop. This eliminates the need for an additional step of welding the conductive component 4 to the end cap 3, thus simplifying the process.In contrast to welding the end cap 3 and the conductive component 4 from the outside, the residual heat generated during the welding of the end cap 3 and the housing 1 is indirectly used for fusion welding the conductive component 4, thus reducing energy consumption during welding. Even though the conductive component 4 and the end cap 3 or the housing 1 are made of different metal materials, no obvious molten metal is visible on a contact surface between the conductive component 4 and the end cap 3 or the housing 1. Instead, the atoms of an upper metal layer dissolve into one another at high temperatures, forming a conductive cross-section. This is similar to laser heat conduction welding and can reduce microcracks to prevent electrolyte leakage, thereby improving the performance and safety of the battery cell 100 during use.

[0080] In some embodiments, it is provided that the distance between the outer edge of the conductive component 4 and the welding area is no more than 15 mm.

[0081] When selecting this distance, both the inherent structure of the conductive component 4 and the available mounting space must be taken into account. Furthermore, the heat generated during the welding of the end cap 3 and the housing 1 must be considered to ensure reliable welding of the conductive component 4.

[0082] In this embodiment, the outer edge of the conductive component 4 is located a short distance from the welding area in order to reliably fusion-weld the conductive component 4 to at least one of the end cap 3 and the housing 1 by utilizing the heat generated during welding. This electrically connects the conductive component 4 to at least one of the end cap 3 and the housing 1, reliably forming a conductive loop and thus improving the electrical conductivity of the battery cell 100.

[0083] In some embodiments, the first tab 22 is a negative tab. The negative tab is made of copper.

[0084] Since the negative tab and the end cap 3 are made of different materials in this embodiment, cracks can form on the surface of the end cap 3 when it is welded from the outside. The residual heat generated during the welding of the end cap 3 and the housing 1 is indirectly used for fusion welding the conductive component 4, thereby reducing energy consumption during welding. Even if the conductive component 4 and the end cap 3 or the housing 1 are made of different metal materials, less molten metal is produced at the contact surface between the conductive component 4 and the end cap 3 or the housing 1.Instead, at high temperatures, the atoms of an upper metal layer dissolve into each other, forming a conductive cross-section, which reduces microcracks to prevent electrolyte leakage and thus improves the performance and safety of the battery cell 100 during use.

[0085] In some embodiments, such as in Fig. As shown in Figure 5, the outer edge of the conductive component 4 and the end cap 3 form a recess-projection fitting system.

[0086] The recess-projection fitting system can extend along the entire circumference of the end cap 3 or along a portion of its circumference. The recess-projection fitting system comprises a recess 31 and a projection embedded in the recess 31. The recess 31 can be located on an inner surface of the end cap 3, while the outer edge of the conductive component 4 acts as the projection. Alternatively, the recess 31 can be located on the outer edge of the conductive component 4, while the projection is located on the inner surface of the end cap 3. The recess-projection fitting system can be positioned in a region near the inner wall of the housing 1 in the radial direction of the end cap 3, allowing the conductive component 4 to be welded using the heat generated during the welding of the end cap 3 and the housing 1.

[0087] Optionally, the conductive component 4 can also have a flat plate structure. In a cylindrical battery, for example, the conductive component 4 is disk-shaped, with an outer side wall of the conductive component 4 being in radial contact with an inner side wall of the housing 1 or being spaced apart from it at a predetermined distance.

[0088] In this embodiment, the outer edge of the conductive component 4 and the end cap 3 form a recess-projection fitting system that positions the conductive component 4 and holds it in a suitable position during welding of the end cap 3 and the housing 1, thus ensuring reliable welding of the conductive component 4. Furthermore, it is possible to increase the number of welding interfaces between the conductive component 4 and the end cap 3 or the housing 1. These multiple welding interfaces are located near the welding area between the end cap 3 and the housing 1, thereby improving the reliability of the electrical connection between the conductive component 4 and the end cap 3 or the housing 1.

[0089] In some embodiments, the conductive component 4 comprises, as in Fig. Figure 5 shows a main body section 41 and a folded section 42. The main body section 41 is electrically connected to the first tab 22, while the folded section 42 is connected to an edge of the main body section 41 and extends towards the end cap 3. A recess 31 is provided in a region of the inner surface of the end cap 3, located near the edge, and the folded section 42 extends into the recess 31.

[0090] The conductive component 4 can be a thin plate or a sheet-like structure. In a cuboid battery cell 100, the main body section 41 can be rectangular, and the folded section 42 can be arranged on at least one side of the main body section 41; in a cylindrical battery cell 100, the main body section 41 can be circular, and the folded section 42 can be arranged on at least a part of one side of the main body section 41 along its circumference.

[0091] The main body section 41 can be electrically connected to the first tab 22 by welding. The folded section 42 can be connected to the outer edge of the main body section 41 by welding, bonding, or a fastening connection. Alternatively, it can be formed integrally with the main body section and implemented by bending. The recess 31 is provided in the area of ​​the inner surface of the end cap 3 that is located near the edge, thus reducing the local thickness of the end cap 3. The folded section 42 acts as a projection of the recess-projection fitting system and extends into the recess 31 to create a fit between the folded section 42 and the recess 31. The folded section 42 is in contact with the recess 31 at least on some of the mating surfaces to facilitate welding of the conductive component 4.

[0092] Since the recess 31 is provided in the end cap 3 in this embodiment, the local thickness of the end cap 3 can be reduced to such an extent that the folded section 42 can be located closer to the welding area between the end cap 3 and the housing 1. Thus, with a given welding power, it is possible to ensure sufficient residual heat when welding the end cap 3 and the housing 1, which improves the welding of the conductive component 4 and the end cap 3 or the housing 1 and guarantees the reliability of the electrical connection, thereby improving the performance of the battery cell 100. Alternatively, the welding power required to join the end cap 3 and the housing 1 can be reduced while still ensuring the welding effect of the conductive component 4.

[0093] In some embodiments, such as in Fig. As shown in Figure 5, an end section of the folded section 42 is in contact with a bottom wall 313 of the recess 31.

[0094] Here, an end surface of the folded section 42, facing away from the main body section 41, is in contact with the bottom wall 313 of the recess 31. Both the end surface of the folded section 42 and the bottom wall 313 of the recess 31 can be planar, which provides good contact and facilitates machining. Alternatively, the end surface of the folded section 42 and the bottom wall 313 fit together by means of convex or other curved surfaces.

[0095] In this embodiment, the end section of the folded section 42 is in contact with the bottom wall 313 of the recess 31, and the interface for joining is located closest to the welding area between the end cap 3 and the housing 1, thereby fully utilizing the residual heat generated during welding, improving the welding of the folded section 42 and the bottom wall 313, and guaranteeing the reliability of the electrical connection, thereby improving the performance of the battery cell 100.

[0096] In some embodiments, as in Fig. Figure 6 shows a guide section 314 provided at an opening of the recess 31 and configured to insert the folded section 42 into the recess 31.

[0097] Here, the guide section 314 is configured such that the opening of the recess 31 tapers from the outside to the inside, so that smooth assembly is possible even if the clearance between the recess 31 and the folded section 42 is small. For example, the guide section 314 can include at least one guide surface, which may be a chamfer, a curved surface, or the like.

[0098] In this embodiment, the guide section 314 is provided at the opening of the recess 31, allowing the folded section 42 to be smoothly installed in the recess 31, thus reducing the requirements for the accuracy of fit between the folded section 42 and the recess 31, facilitating the assembly of the end cap 3, preventing deformation of the conductive component 4 during assembly, and increasing assembly efficiency.

[0099] In some embodiments, it is provided that the end surface of the main body section 41, which faces away from the first tab 22, is in contact with the inner surface of the end cap 3.

[0100] In this case, both the end surface of the main body section 41, which faces away from the first tab 22, and the inner surface of the end cap 3 can be flat to achieve contact over the entire surface. Alternatively, the two can be in partial contact.

[0101] In this embodiment, the contact area between the conductive component 4 and the end cap 3 can be increased, while the electrical connection is established by locally welding the conductive component 4 and the end cap 3 or the housing 1, thereby improving the reliability of the electrical connection between the conductive component 4 and the end cap 3 and the performance of the battery cell 100.

[0102] In some embodiments, such as in Fig. As shown in Figure 7, one end of the housing 1 protrudes outwards as a whole near the end cap 3 to form a step 12 on an inner side wall of the housing 1, with the main body section 41 abutting the step 12.

[0103] Here, the projection of the housing 1 has a larger inner and outer diameter than the main body section to ensure that the thickness of a side wall of the housing 1 meets the strength requirements. The step 12 can be a horizontal or otherwise shaped surface, with the main body section 41 extending towards the inner side wall of the housing 1 to overlap the step 12. For example, the battery cell 100 is cylindrical, with the end of the housing 1 projecting radially outwards near the end cap 3, forming a step 12 that can be configured as a complete ring. Alternatively, several steps 12 can be provided, spaced apart from one another along the circumference.

[0104] Since, in this embodiment, the main body section 41 rests against the step 12, an edge region of the main body section 41 can be stably supported, and the conductive component 4 is more stable after assembly. This allows the conductive component 4 to be reliably welded by utilizing the residual heat generated during the welding of the end cap 3 and the housing 1. Furthermore, this prevents the main body section 41 from deforming in any direction relative to the electrode arrangement 2, thus avoiding damage to the electrode plates in the electrode body 21 or to the first tab 22 due to deformation of the main body section 41 and ensuring the operational performance of the battery cell 100.Based on such a design, a gap between the housing 1 and the electrode arrangement 2 can also be arranged offset from a connection surface between the housing 1 and the end cap 3 in order to reduce the risk of electrolyte leakage at the connection surface between the housing 1 and the end cap 3.

[0105] In some embodiments, the folded section 42 extends along the entire circumference of the main body section 41.

[0106] For example, the battery cell 100 is cylindrical, the main body section 41 is disc-shaped and the folded section 42 is annular, wherein an angle between the folded section 42 and the main body section 41 can be a right angle, an acute angle or an obtuse angle, which depends mainly on the angles of the side walls of the recess 31.

[0107] In this embodiment, the folded section 42 extends along the entire circumference of the main body section 41, thereby increasing the overall structural strength of the conductive component 4 to prevent deformation. Furthermore, the folded section 42 can be welded to its entire circumference using the residual heat generated during the welding of the end cap 3 and the housing 1. This improves the reliability of the electrical connection between the conductive component 4 and the housing 1 or the end cap 3, and ensures the reliable operation of the battery cell 100. The overcurrent capacity of the conductive component 4 can also be improved.

[0108] In some embodiments, such as in Fig. As shown in Figure 8, the folded section 42 comprises several folded subsections 42', the several folded subsections 42' being spaced apart from each other along the circumference of the main body section 41.

[0109] The multiple sections 42' can be spaced evenly along the circumference such that uniformly distributed electrical connection areas are formed between the multiple folded sections 42' and the housing 1 or the end cap 3. This improves the stability of the conductive component 4 during assembly, and ensures that the conductive component 4 has uniform electrical conductivity along its circumference.

[0110] In a disk-shaped main body section 41, the folded subsections 42' optionally each have an arc length of a, where 0 < a < 300 mm, where the number of folded subsections 42' n and the angle between adjacent folded subsections 42' α is, where 0 < α < 360°, where: (d + 2D) * π = a * n + n * α / 360° * (d + 2D) * π.

[0111] In this embodiment, the folded section 42 is divided into several spaced-apart folded subsections 42', which facilitates the folding process, improves manufacturability, avoids overlap between adjacent folded subsections 42', ensures smooth assembly even with a small clearance between the recess 31 and the folded section 42, and guarantees a uniform thickness of the folded subsections 42', thereby facilitating welding by utilizing the residual heat generated during welding of the end cap 3 and the housing 1.

[0112] In some embodiments, such as in Fig. As shown in Figures 9 to 12, the conductive component 4 has a sheet metal structure, wherein the folded section 42 and the main body section 41 are formed in one piece, and wherein a weakened section 43 is provided in a connection area between the folded section 42 and the main body section 41.

[0113] Here, the folded section 42 is in the same plane as the main body section 41 before it is folded. The weakened section 43 provided at the base of the folded section 42 helps to bend the folded section 42 towards one side of the main body section 41. Fig. Figure 11 shows a schematic representation of the conductive component 4, which has been bent. Optionally, the weakened section 43 can be a section with reduced thickness. For example, the section with reduced thickness is formed by a depression that can be provided on the inside of the folded section 42 in the bending direction. Alternatively, the weakened section 43 can be achieved by locally reducing the material strength.

[0114] Optionally, the weakened section 43 includes a depression with a depth of B, where L * 30% ≤ B ≤ L * 90%, and where L is the thickness of the conductive component 4.

[0115] Optionally, the proportion in terms of dimensions that the folded section 42 occupies in the circumferential direction of the main body section 41 is between 10% and 99%.

[0116] In this embodiment, the weakened section 43 is provided to facilitate the bending of the folded section 42, to reduce the external force to be exerted during bending, to decrease the deformation of the main body section 41, and to improve the reliability of the electrical connections between the main body section 41 and the first tab 22, as well as between the folded section 42 and the end cap 3 or the housing 1.

[0117] In a first embodiment, as in Fig. Figures 5 to 13 show the recess 31 in the outer side wall of the end cap 3.

[0118] Here, the recess 31 comprises only the bottom wall 313 and a first inner side wall 311, and the outer side wall of the recess 31 is open. When welding the end cap 3 and the housing 1, the folded section 42 can be welded to at least one of the bottom wall 313 and the first inner side wall 311. The end cap 3 can comprise a first section 3A and a second section 3B. The first section 3A is superimposed on the second section 3B. The contour dimension of the first section 3A is smaller than the contour dimension of the second section 3B over its entire circumference. The recess 31 is formed in the area where the first section 3A is recessed inwards relative to the second section 3B. In the case of a cylindrical battery cell 100, the end cap 3 is, for example, B. disc-shaped, wherein the bottom wall 313 is a circular flat surface and the first inner side wall 311 is a cylindrical surface.

[0119] In this embodiment, the recess 31 is easy to machine, which reduces the requirements for the fit between the recess 31 and the folded section 42, thus facilitating assembly. Furthermore, the contour dimension of the end cap 3, for example the radial dimension of a cylindrical battery cell 100, can be minimized using the recess 31, thereby reducing the overall size of the battery cell 100.

[0120] To improve the effectiveness of the electrical connection, the interface for joining the end section of the folded section 42 and the recess 31 can, firstly, be located closer to the weld area between the housing 1 and the recess 31. This facilitates welding the folded section 42 by utilizing the residual heat generated during welding the end cap 3 and the housing 1. Secondly, the outer side wall of the folded section 42 is located closer to the inner side wall of the housing 1. This helps to create a weld interface between the outer side wall of the folded section 42 and the inner side wall of the housing 1, again utilizing the residual heat generated during welding to establish the electrical connection between the conductive component 4 and the housing 1.In a third aspect, during the welding of the end cap 3 and the housing 1, a small amount of solder flux can flow into the fit between the folded section 42 and the end cap 3 or the housing 1, further improving the reliability of the conductive component 4 during welding. All of the above advantages can lead to improved reliability of the electrical connection of the conductive component 4, thereby improving the electrical conductivity of the battery cell 100.

[0121] Furthermore, in an embodiment where the end of the housing 1 projects radially outwards near the end cap 3, forming the step 12, such a recess 31 allows the main body section 41 to extend as far as possible towards the outer edge of the end cap 3, thereby increasing the length of the overlap between the main body section 41 and the step 12. This improves the stability of the conductive component 4 during assembly and reliably prevents deformation of the conductive component 4 and damage to the electrode arrangement 2.

[0122] In some embodiments, such as in Fig. As shown in Figure 5, the outer side wall of the folded section 42 is in contact with the inner side wall of the housing 1.

[0123] The contact mentioned herein includes both a perfect fit and the presence of a small gap caused by an assembly error.

[0124] In this embodiment, a welding interface is formed between the outer side wall of the folded section 42 and the inner side wall of the housing 1, and when welding the housing 1 to the end cap 3, the residual heat generated during welding is used to weld the folded section 42 to the housing 1 in order to establish the electrical connection between the folded section 42 and the housing 1 and thus to realize a reliable current flow from the first tab 22 to the housing 1, thereby improving the electrical conductivity of the battery cell 100.

[0125] In some embodiments, the battery cell 100 is cylindrical, as in Fig. Figure 8 shows the main body section 41 being circular and having a diameter of d, where 10 mm ≤ d ≤ 100 mm, and the folded section 42 having an extent of D, where 0.2 mm ≤ D ≤ 1 mm.

[0126] In some embodiments, such as in Fig. As shown in Figure 13, the recess 31 has a depth of H1, where 0.1 mm ≤ H1 ≤ 1.8 mm and 0 ≤ |L + D + H-H1-h| ≤ 0.2 mm, thus fulfilling the manufacturing requirements for assembly and welding. Here, H is the thickness of the end cap 3, L is the thickness of the conductive component 4, D is the extent of the folded section 42, and h is the distance between the step 12 and an outer end face of the housing 1, the step being formed on the inner side wall of the housing 1 by the outwardly projecting end of the housing 1 near the end cap 3.

[0127] In some embodiments, it is provided that, as in Fig. Figure 13 shows that the end cap 3 is circular and has a diameter of C1, and that the bottom wall 313 of the recess 31 has a width of C2, where 10 mm ≤ C1 ≤ 100 mm and 0.2 mm ≤ C2 ≤ 2 mm.

[0128] In some embodiments, it is provided that, as in Fig. Figure 7 shows that the step 12 has a width of W, and that the distance between the step 12 and the outer end face of the housing is 1 h, where 0.2 mm ≤ W ≤ 1.0 mm and 1 mm ≤ h ≤ 10 mm.

[0129] In some embodiments, it is provided that, as in Fig. 10 and Fig. 13 shows that the conductive component 4 has a thickness of L, where 0.2 mm ≤ L ≤ 1.0 mm; and that the end cap 3 has a thickness of H, where 0.2 mm ≤ H ≤ 2.0 mm; and / or that the electrode body 21 is cylindrical and has a diameter of P, as shown in Fig. Figure 4 shows where 5 mm ≤ P ≤ 97 mm.

[0130] Fig. Figures 14 to 16 show a schematic structural view of a second embodiment. In some embodiments, it is provided that, as in Fig. 14 and Fig. 15 shown that the recess 31 is located in a region of the inner surface of the end cap 3 which is near the edge, that an inner wall of the recess 31 comprises a first inner side wall 311 and a first outer side wall 312, and that the folded section 42 extends into the recess 31 and is in contact with at least a part of the inner wall of the recess 31.

[0131] Here, the inner wall of the recess 31 comprises the first inner side wall 311, the first outer side wall 312, and the bottom wall 313. The first inner side wall 311 and the first outer side wall 312 are arranged opposite each other, and the bottom wall 313 is connected between the first inner side wall 311 and the first outer side wall 312. The recess 31 can be configured as an annular groove extending around its entire circumference or divided into several segments spaced apart along its circumference. For example, in the case of a disc-shaped end cap, the recess 31 is configured as an annular groove. Since the recess 31 is located in the area near the edge of the end cap 3, there is a predetermined distance between the outer side wall of the folded section 42 and the inner wall of the housing 1.

[0132] Optionally, a guide section 314 can be provided at the opening of the recess 31. For example, the guide section 314 can comprise guide surfaces located on the first inner side wall 311 and the first outer side wall 312, with both guide surfaces positioned at the opening of the recess 31. The distance between the two guide surfaces gradually increases from the inside out to guide the folded section 42 into the recess 31. Alternatively, the guide section 314 can also comprise a guide surface located only on the first inner side wall 311 or the first outer side wall 312. The guide surface can be, for example, a chamfer or a curved surface.

[0133] In this embodiment, the recess 31 is provided in the area near the edge of the end cap 3, so that the mating surfaces between the recess 31 and the end cap 3 and the housing 1 are offset. This prevents the soldering flux from penetrating the recess 31 during welding of the end cap 3 and the housing 1. Furthermore, the welding of the conductive component 4 and the end cap 3 is achieved solely by utilizing the residual heat generated during the welding process. In particular, the welding of the folded section 42 and the recess 31 is also achieved by utilizing this residual heat. Since the conductive component 4 and the end cap 3 are made of different metallic materials, for example, the conductive part 4 being made of copper and the end cap 3 of steel, it is possible to prevent molten copper or a copper alloy from penetrating a grain boundary in the steel within a weld zone.Furthermore, cracks at the end cap 3 can be avoided, thus solving the problem of outward penetration of the electrolyte of battery cell 100 after prolonged use and ensuring the performance and operational safety of battery cell 100.

[0134] In some embodiments, it is provided that, as in Fig. Figure 15 shows that the folded section 42 has a second inner side wall 421 and a second outer side wall 422, wherein the second inner side wall 421 is in contact with the first inner side wall 311 and / or the second outer side wall 422 is in contact with the first outer side wall 312.

[0135] Here, the folded section 42 and the inner side wall of the recess 31 are in contact with each other when the second inner side wall 421 is in contact with the first inner side wall 311. When the second outer side wall 422 is in contact with the first outer side wall 312, the folded section 42 and the outer side wall of the recess 31 are in contact with each other. Optionally, the end face of the folded section 42, which faces away from the main body section 41, can also be in contact with the bottom wall 313 of the recess 31.

[0136] In this embodiment, the respective inner and / or outer side walls of the folded section 42 and the recess 31 are in contact, allowing the conductive component 4 to be positioned in such a way as to improve its stability during assembly. Furthermore, the folded section 42 and the recess 31 can be welded together more effectively by utilizing the residual heat generated during the welding of the end cap 3 and the housing 1. In addition, the contact between the side walls creates an interface between the folded section 42 and the recess 31, enabling reliable welding. This improves the reliability of the electrical connection between the conductive component 4 and the end cap 3, and thus the electrical conductivity of the battery cell 100.

[0137] In some embodiments, it is provided that, as in Fig. 14 showed that the step 12 has a width of W, and that the distance between the step 12 and the outer end face of the housing is 1 h, where 0.2 mm ≤ W ≤ 5.0 mm and 1 mm ≤ h ≤ 10 mm.

[0138] Optionally, the end cap 3 in the second embodiment, as shown in Fig. Figure 16 shows a diameter of C1, where 5 mm ≤ C1 ≤ 97 mm. The diameter of the first inner side wall 311 is L1. The distance between the first outer side wall 312 and the edge of the end cap 3 is H4. The depth of the recess 31 is H1, where 0.1 ≤ H1 ≤ 1.8 mm, and the width of the bottom wall 313 of the recess 31 is H2. To facilitate the insertion of the folded section 42 into the recess 31, a guide angle is provided at the opening of the recess 31, where 90 ≤ γ < 180. The width of the upper flare is H3, where 2 * H4 + 2 * H2 + H3 - H2 + L1 = C1. Furthermore, it holds true that: d + 2L = 2 * H2 + H3-H2 + L1, so that the folded section 42 can be directly facing the recess 31 of the end cap 3.To configure the thickness of the folded section 42 so that it can be precisely inserted into the end cap 3 and the gap requirement for laser melting of the side wall of the end cap 3 and the folded section 42 is met, 0 ≤ |H2-L| ≤ 0.05 mm must apply. Furthermore, 0 ≤ |(H1 + H-H1 + L) - (h-d1)| ≤ 0.05 mm must apply to ensure a sealing interface and an apparent size. It is further stipulated that the parameters specified in the first embodiment also apply to the second embodiment.

[0139] Since in this embodiment the recess 31 is provided in the area near the edge of the end cap 3, the step 12 must extend over a large width so that the main body section 41 of the conductive component 4 can overlap the step 12.

[0140] The specific structure of battery cell 100 of the present disclosure is described in detail below using the example of a cylindrical battery cell.

[0141] In the first embodiment, as in Fig. As shown in Figures 3 to 13, the battery cell 100 comprises a housing 1, an electrode assembly 2, an end cap 3, and a conductive component 4. An opening 11 is provided at one end of the housing 1, while the other end is closed and provided with an electrode terminal 5. The end cap 3 closes the opening 11 and is fixed by welding, for example, using laser welding. The electrode assembly 2 comprises an electrode body 21, a first tab 22, and a second tab 23. The first tab 22 and the second tab 23 each extend from the ends of the electrode body 21 along the winding axis, with the first tab 22 being a negative tab and the second tab 23 being a positive tab.

[0142] As in Fig. As shown in Figure 5, the conductive component 4 comprises a main body section 41 and a folded section 42, wherein the folded section 42 is bent relative to the main body section 41 in the direction of the side facing away from the electrode arrangement 2, and wherein the folded section 42 has a second inner side wall 421 and a second outer side wall 422. The end face of the main body section 41 facing the electrode arrangement 2 is electrically connected to the first tab 22, while the end face of the main body section 41 facing away from the electrode arrangement fits an inner surface of the end cap 3. A recess 31 is provided in the inner surface of the end cap 3, wherein the recess 31 is located on an outer side wall of the end cap 3, such that an inner wall of the recess 31 comprises only a first inner side wall 311 and a bottom wall 313.The first inner side wall 311 fits the second inner side wall 421 of the folded section 42, and the second outer side wall 422 is flush with the outer side wall of the end cap 3, which has the largest dimension.

[0143] As in Fig. As shown in Figure 7, the end of the housing 1 protrudes outwards as a whole near the end cap 3 to form a step 12 on an inner side wall of the housing 1, with the main body section 41 abutting the step 12, and with the second outer side wall 422 fitting the inner wall of the housing 1.

[0144] As in Fig. As shown in Figure 8, the folded section 42 comprises several folded subsections 42', the several folded subsections 42' being spaced apart from one another along the circumference of the main body section 41. For example, two, three, or four folded subsections 42' may be provided. A through-hole may be provided in the center of the main body section 41.

[0145] As in Fig. As shown in Figure 9, a weakened section 43 may be provided in an area where the main body section 41 is connected to the folded section 42 to facilitate bending of the folded section 42.

[0146] In the second embodiment, as in Fig. As shown in Figures 14 to 16, the difference from the first embodiment is that the recess 31 is provided in the area near the edge of the inner surface of the end cap 3, and the inner wall of the recess 31 comprises the first inner side wall 311, the first outer side wall 312, and the bottom wall 313, wherein the first inner side wall 311 and the first outer side wall 312 are arranged opposite each other, and wherein the bottom wall 313 is connected between the first inner side wall 311 and the first outer side wall 312. Since the recess 31 is located in the area near the edge of the end cap 3, there is a predetermined distance between the outer side wall of the folded section 42 and the inner wall of the housing 1.

[0147] Optionally, as in Fig. As shown in Figure 15, a guide section 314 is provided at the opening of the recess 31, wherein the guide section 314 may comprise guide surfaces provided on the first inner side wall 311 and the first outer side wall 312. The two guide surfaces are located at the opening of the recess 31, the distance between the two guide surfaces gradually increasing from the inside to the outside in order to guide the folded section 42 into the recess 31. The guide surface may, for example, be a chamfer or a curved surface.

[0148] Furthermore, the present revelation offers several examples of how to do so in Fig. Figure 17 shows an unclaimed method for manufacturing a battery cell 100, the method comprising the following: a step S110 for providing components in which a housing 1, an end cap 3, an electrode assembly 2 and a conductive component 4 are provided, wherein an opening 11 is provided at an end section of the housing 1, and wherein the electrode assembly 2 comprises an electrode body 21 and a first tab 22, wherein the first tab 22 extends out of an end of the electrode body 21; a step S120 for attaching the electrode, in which the electrode assembly 2 is attached in the housing 1 and the conductive component 4 is electrically connected to the first tab 22; and a step S130 for attaching the end cap, wherein the opening 11 is closed by the end cap 3 to allow the conductive component 4 to be located between the electrode arrangement 2 and the end cap 3, wherein the outer circumference of the end cap 3 is attached to the housing 1 by welding, wherein the welded conductive component 4 is electrically connected to the end cap 3, and wherein an outer edge of the conductive component 4 extends at a position near a weld area.

[0149] Steps S110 to S130 are executed sequentially.

[0150] In this embodiment, the outer edge of the conductive component 4 extends near the welding area between the end cap 3 and the housing 1. This allows the conductive component 4 to be fusion-welded to at least one of the end cap 3 and the housing 1 by the heat generated when the end cap 3 is welded to the opening 11 of the housing 1. After cooling and solidification, a single-piece connection interface is formed, so that the conductive component 4 is electrically connected to at least one of the end cap 3 and the housing 1, forming a conductive loop. This eliminates the need for an additional step of welding the conductive component 4 to the end cap 3, thus simplifying the process.In contrast to welding the end cap 3 and the conductive component 4 from the outside, the residual heat generated during the welding of the end cap 3 and the housing 1 is indirectly used for fusion welding the conductive component 4, thus reducing energy consumption during welding. Even though the conductive component 4 and the end cap 3 or the housing 1 are made of different metal materials, no obvious molten metal is visible on a contact surface between the conductive component 4 and the end cap 3 or the housing 1. Instead, the atoms of an upper metal layer dissolve into one another at high temperatures, forming a conductive cross-section. This is similar to laser heat conduction welding and can reduce microcracks to prevent electrolyte leakage, thereby improving the performance and safety of the battery cell 100 during use.

[0151] In some embodiments, the conductive component 4 comprises a main body section 41 and a folded section 42, wherein the main body section 41 is configured to be electrically connected to the first tab 22, while the folded section 42 is connected to an edge of the main body section 41, the main body section 41 and the folded section 42 lying in the same plane before assembly. Furthermore, the manufacturing method comprises the following:

[0152] Bending the folded section 42 in the direction of the main body section 41 and forming an obtuse angle between the folded section 42 and the main body section 41, so that the conductive component 4 sits firmly against an inner wall of the housing 1 when installed in the housing 1.

[0153] Here, the angle between the folded section 42 and the main body section 41 is θ, where 90° ≤ θ ≤ 120°.

[0154] In this embodiment, the folded section 42 is bent from the main body section 41 during assembly so that an obtuse angle is formed between them, whereby the folded section 42 can be pressed against the inner wall of the housing 1 in order to be subjected to a certain compressive force when the conductive component 4 is installed in the housing 1, so that the folded section 42 can lie firmly against the inner wall of the housing 1, thereby improving the reliability of the electrical connection between the conductive component 4 and the housing 1 and thus the electrical conductivity of the battery cell 100.

[0155] Although the present disclosure has been described with reference to preferred embodiments, various modifications can be made and equivalents provided to replace the components without departing from the scope of this disclosure. In particular, the technical features mentioned in the embodiments can be combined in any way, provided they do not conflict with one another. The present disclosure is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions that fall within the scope of the claims.

Claims

[1] Battery cell (100), comprising: a housing (1) wherein an opening (11) is provided at an end section of the housing (1); an electrode arrangement (2) arranged inside the housing (1), wherein the electrode arrangement (2) comprises an electrode body (21) and a first tab (22), the first tab (22) extending from an end of the electrode body (21); an end cap (3) that closes the opening (11), the outer circumference of the end cap (3) being attached to the housing (1) by welding; and a conductive component (4) arranged between the electrode arrangement (2) and the end cap (3), wherein the conductive component (4) is electrically connected to the first tab (22), wherein the conductive component (4) is electrically connected to at least one of the end cap (3) and the housing (1), and wherein an outer edge of the conductive component (4) extends at a position near a welding area. [2] Battery cell (100) according to claim 1, wherein the distance between the outer edge of the conductive component (4) and the welding area is not greater than 15 mm. [3] Battery cell (100) according to claim 1 or 2, wherein the first tab (22) is a negative tab. [4] Battery cell (100) according to one of claims 1 to 3, wherein the outer edge of the conductive component (4) and the end cap (3) form a recess-protrusion fitting system. [5] Battery cell (100) according to any one of claims 1 to 4, wherein the conductive component (4) comprises: a main body section (41) which is electrically connected to the first tab (22); and a folded section (42) which is connected to an edge of the main body section (41) and extends towards the end cap (3); wherein a recess (31) is provided in an area of ​​an inner surface of the end cap (3) which is located near the edge, and wherein the folded section (42) extends into the recess (31). [6] Battery cell (100) according to claim 5, wherein an end section of the folded section (42) is in contact with a bottom wall (313) of the recess (31). [7] Battery cell (100) according to claim 5 or 6, wherein a guide section (314) is provided at an opening of the recess (31) and is configured to insert the folded section (42) into the recess (31). [8] Battery cell (100) according to one of claims 5 to 7, wherein the end surface of the main body section (41) facing away from the first tab (22) is in contact with the inner surface of the end cap (3). [9] Battery cell (100) according to any one of claims 5 to 8, wherein the end of the housing (1) protrudes outwards as a whole near the end cap (3) to form a step (12) on an inner side wall of the housing (1), and wherein the main body section (41) rests against the step (12). [10] Battery cell (100) according to any one of claims 5 to 9, wherein the folded section (42) extends along the entire circumference of the main body section (41). [11] Battery cell (100) according to any one of claims 5 to 9, wherein the folded section (42) comprises several folded subsections (42') and these several folded subsections (42') are spaced apart from each other along the circumference of the main body section (41). [12] Battery cell (100) according to one of claims 5 to 11, wherein the conductive component (4) has a sheet metal structure, wherein the folded section (42) and the main body section (41) are formed in one piece, and wherein a weakened section (43) is provided in a connection area between the folded section (42) and the main body section (41). [13] Battery cell (100) according to one of claims 5 to 12, wherein the recess (31) is arranged in an outer side wall of the end cap (3). [14] Battery cell (100) according to claim 13, wherein an outer side wall of the folded section (42) is in contact with the inner side wall of the housing (1). [15] Battery cell (100) according to one of claims 5 to 12, wherein the recess (31) is provided in a region of the inner surface of the end cap (3) which is located near the edge, wherein an inner wall of the recess (31) comprises a first inner side wall (311) and a first outer side wall (312), wherein the folded section (42) extends into the recess (31) and is in contact with at least a part of the inner wall of the recess (31). [16] Battery cell (100) according to claim 15, wherein the folded section (42) has a second inner side wall (421) and a second outer side wall (422), wherein the second inner side wall (421) is in contact with the first inner side wall (311) and / or the second outer side wall (422) is in contact with the first outer side wall (312). [17] Battery cell (100) according to any one of claims 5 to 16, wherein the battery cell (100) is cylindrical, while the main body section (41) is circular and has a diameter of d, wherein 10 mm ≤ d ≤ 100 mm, wherein the folded section (42) has an extent of D, wherein 0.2 mm ≤ D ≤ 1 mm. [18] Battery cell (100) according to any one of claims 5 to 17, wherein the recess (31) has a depth of H1, wherein 0.1 mm ≤ H1 ≤ 1.8 mm and 0 ≤ |L + D + H-H1-h| ≤ 0.2 mm, wherein H is the thickness of the end cap (3), L is the thickness of the conductive component (4), D is the extent of the folded section (42) and h is the distance between the step (12) and an outer end face of the housing (1), wherein the step on the inner side wall of the housing (1) is formed by the end of the housing (1) near the end cap (3), which protrudes outwards as a whole. [19] Battery cell (100) according to any one of claims 5 to 18, wherein the end cap (3) is circular and has a diameter of C1, while the bottom wall (313) of the recess (31) has a width of C2, wherein 10 mm ≤ C1 ≤ 100 mm and 0.2 mm ≤ C2 ≤ 2 mm. [20] Battery cell (100) according to any one of claims 13, 14 and 17 to 19, wherein the end of the housing (1) protrudes outwards as a whole near the end cap (3) to form a step (12) on an inner side wall of the housing (1), and wherein the main body section (41) abuts the step (12); wherein the step (12) has a width of W and the distance between the step (12) and the outer end face of the housing (1) is h, wherein 0.2 mm ≤ W ≤ 1.0 mm and 1 mm ≤ h ≤ 10 mm. [21] Battery cell (100) according to any one of claims 15 to 19, wherein the end of the housing (1) protrudes outwards as a whole near the end cap (3) to form a step (12) on an inner side wall of the housing (1), and wherein the main body section (41) abuts the step (12); wherein the step (12) has a width of W and the distance between the step (12) and the outer end face of the housing (1) is h, wherein 0.2 mm ≤ W ≤ 5.0 mm and 1 mm ≤ h ≤ 10 mm. [22] Battery cell (100) according to any one of claims 1 to 21, wherein the conductive component (4) has a thickness of L, wherein 0.2 mm ≤ L ≤ 1.0 mm; wherein the end cap (3) has a thickness of H, wherein 0.2 mm ≤ H ≤ 2.0 mm; and / or wherein the electrode body (21) is cylindrical and has a diameter of P, wherein 5 mm ≤ P ≤ 97 mm. [23] Battery (200), comprising: a housing arrangement (201); and a battery cell (200) according to one of claims 1 to 22, wherein the battery cell (200) is arranged within the housing arrangement (201). [24] Power-consuming device comprising a battery (200) according to claim 23, wherein the battery (200) is configured to supply the power-consuming device with electrical energy.

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