Battery cell, battery device and electric apparatus
By using pressure-reducing components and air-guiding structures in the battery cells, the problem of unstable connection between the current collector and the end cap was solved, improving the stability and safety of the battery, reducing welding defects and heat, and enhancing the overall performance of the battery.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- CONTEMPORARY AMPEREX TECHNOLOGY CO LTD
- Filing Date
- 2025-09-12
- Publication Date
- 2026-07-30
AI Technical Summary
In the existing technology, the connection between the current collector and the end cap of the battery cell is unstable, which can easily lead to gaps and welding defects, affecting the safety and stability of the battery.
A pressure-retaining component is used between the end cap and the manifold. The pressure-retaining component includes a pressure-retaining part and a protrusion part, which together press against the manifold. Welding forms a weld mark, which reduces the deformation of the manifold, increases the contact area, and provides a venting space and venting holes to facilitate pressure relief, reduce welding heat and safety risks.
It improves the connection stability between the current collector and the end cap, reduces welding defects, enhances the battery's safety and sealing performance, and reduces the risk of heat generation during the welding process.
Smart Images
Figure CN2025121045_30072026_PF_FP_ABST
Abstract
Description
Battery cells, battery devices and electrical equipment
[0001] Priority information
[0002] This application claims priority and benefits to patent application No. 202510124951.8, filed with the China National Intellectual Property Administration on January 26, 2025, the entire contents of which are incorporated herein by reference. Technical Field
[0003] This application relates to the field of battery technology, specifically to a battery cell, a battery device, and an electrical device. Background Technology
[0004] In related technologies, batteries are widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. A single battery cell may include electrode components, end caps, and current collectors, with the current collector connecting the electrode components and end caps. Therefore, how to improve the stability of the connection between the current collector and the end caps has become a technical problem to be solved. Summary of the Invention
[0005] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device that can improve the stability of the connection between the current collector and the end cover.
[0006] In a first aspect, this application provides a battery cell, which includes a housing, an electrode assembly, a current collector, and a pressing member. The housing includes a surrounding wall and an end cap connected to the surrounding wall. The surrounding wall has a receiving space. The end cap includes a body and a protrusion protruding from the body. The protrusion is at least partially located in the receiving space and abuts against the inner surface of the surrounding wall. The electrode assembly is disposed in the receiving space. The current collector is disposed in the receiving space and located between the end cap and the electrode assembly. The pressing member is located between the end cap and the current collector. The pressing member includes a pressing portion near the protrusion. The pressing portion and the protrusion together press against the current collector. The protrusion is welded to the current collector to form a solder mark.
[0007] In the above embodiments, when assembling the end cover, the pressing part and the protrusion jointly press against the collector plate, which can reduce the deformation of the collector plate, which is beneficial to reduce the gap between the collector plate and the protrusion, thereby reducing welding defects between the collector plate and the protrusion, and thus improving the stability of the connection between the collector plate and the end cover.
[0008] In some embodiments, the plane of the pressing portion facing the collector plate is flush with the plane of the protruding portion facing the collector plate.
[0009] In the above embodiment, the plane of the pressing part facing the collector plate is flush with the plane of the protrusion facing the collector plate, so that the pressing part and the protrusion can jointly press against the collector plate, which helps to reduce the deformation of the collector plate and thus reduce the gap between the collector plate and the protrusion.
[0010] In some embodiments, a groove is formed on the side of the protrusion facing away from the collector plate.
[0011] In the above embodiments, the groove can reduce the thickness of the protrusion, which can reduce the welding power required to weld the protrusion to the collector plate, reduce heat generation, and thus reduce the risk of other components being burned.
[0012] In some implementations, the groove extends circumferentially along the body.
[0013] In the above embodiment, the groove extends circumferentially along the body, which can reduce the thickness of the protrusion extending circumferentially along the body. This can reduce the welding power required to weld the protrusion to the collector plate, reduce heat generation, and thus reduce the risk of other components being burned.
[0014] In some embodiments, the end cap is provided with a pressure relief section, and the pressure-blocking section surrounds an air-guiding space corresponding to the pressure relief section.
[0015] In the above embodiment, a gas guiding space is provided between the pressure-relief part and the pressure-reducing part, so that gas can reach the pressure-reducing part through the gas guiding space, thereby reducing the risk of the pressure-relief part being crushed by the pressure-relief part, and allowing gas to be smoothly discharged when the pressure-reducing part is actuated, thereby improving the safety performance of the battery cell.
[0016] In some embodiments, the pressing part includes a first pressing surface and a second pressing surface facing away from each other. The first pressing surface abuts against the end cap, and the second pressing surface abuts against the collector plate. The air guiding space is a recessed groove extending from the first pressing surface to the second pressing surface. The pressing part also includes a connecting part connected to the side of the recessed groove. The connecting part is provided with an air guiding hole communicating with the recessed groove. The air guiding hole penetrates the connecting part along the thickness direction of the end cap.
[0017] In the above embodiments, the venting space formed by the sink can reduce the risk of the pressure relief part being damaged by the pressure-relief part. The vent is connected to the sink, allowing gas to enter the venting space through the vent, which facilitates smooth venting when the pressure relief part is actuated, thereby improving the safety performance of the battery cell. The connecting part can increase the contact area between the pressure-relief part and the current collector, reducing the deformation of the current collector.
[0018] In some embodiments, there are multiple air guide holes, which are spaced apart.
[0019] In the above embodiments, multiple vent holes can increase the rate at which gas enters the vent space, which is more conducive to smooth exhaust when the pressure relief section is actuated, thereby greatly improving the safety performance of the battery cell.
[0020] In some embodiments, the pressing part includes a first pressing surface and a second pressing surface facing away from each other. The first pressing surface abuts against the end cap, the second pressing surface abuts against the collector plate, and the air guiding space is a through hole penetrating the first pressing surface and the second pressing surface.
[0021] In the above embodiment, the venting space is a through hole that penetrates the first pressure surface and the second pressure surface, which can increase the venting space and facilitate smooth venting when the pressure relief part is actuated, thereby improving the safety performance of the battery cell.
[0022] In some embodiments, the walls of the through hole converge from the first pressing surface to the second pressing surface.
[0023] In the above embodiment, the hole wall of the through hole converges from the first pressing surface to the second pressing surface, which can increase the area of the second pressing surface, thereby increasing the contact area between the pressing part and the collecting plate, which helps to reduce the deformation of the collecting plate.
[0024] In some embodiments, the pressure relief section is provided with a weight reduction hole spaced apart from the air guide space, and the weight reduction hole is located on one side of the pressure relief section along the radial direction of the end cap.
[0025] In the above embodiments, the weight-reducing holes can reduce the weight of the pressure component, while also reducing space occupation and facilitating the movement of the electrolyte.
[0026] In some embodiments, the pressure relief portion is configured as a pressure relief hole; or, the pressure relief portion is configured as a groove; or, the pressure relief portion is configured as a weakening portion.
[0027] In the above technical solutions, by setting the pressure relief part as a pressure relief hole, a groove, or a weakening part, more options can be provided for the design of the pressure relief part to meet different usage requirements.
[0028] In some embodiments, the enclosure has an opening, an end cap seals the opening, and the edge of the end cap is welded to the enclosure.
[0029] In the above embodiments, the end cap and the enclosure are fixed by welding, which can improve the connection strength between the end cap and the enclosure. During the welding process, the protrusion can release the welding stress through deformation, thereby reducing the risk of deformation and cracking in the welding area, improving the sealing performance, and thus improving the sealing performance of the battery cell.
[0030] In some embodiments, the enclosure has an outer end face surrounding the opening, which is welded to the inner surface of the body so that the enclosure and the end cap are integrated.
[0031] In the above embodiment, the inner surface of the main body abuts against the outer end face, which reduces the internal space occupied by the main body in the enclosure. When assembling the end cap and the enclosure, the outer end face can serve as an upper limit in the thickness direction of the end cap.
[0032] In some embodiments, the current collector includes a first current collector and a second current collector connected to the first current collector. The second current collector surrounds the outside of the first current collector. The first current collector is welded to an electrode assembly, and the second current collector is welded to a protrusion to form a solder mark.
[0033] In the above embodiments, welding can reduce the contact resistance between the first current collector and the electrode assembly and the contact resistance between the second current collector and the protrusion, which is beneficial to improving the current carrying capacity.
[0034] Secondly, this application provides a battery device that includes the battery cell in any of the above embodiments.
[0035] Thirdly, this application provides an electrical device that includes a battery cell or battery device as described in any of the above embodiments, wherein the battery cell or battery device is used to provide electrical energy.
[0036] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description
[0037] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0038] Figure 1 is a schematic diagram of the vehicle structure according to some embodiments of this application;
[0039] Figure 2 is an exploded structural diagram of a battery device according to some embodiments of this application;
[0040] Figure 3 is a schematic diagram of the structure of a battery cell according to some embodiments of this application;
[0041] Figure 4 is an exploded structural diagram of a battery cell according to some embodiments of this application;
[0042] Figure 5 is a cross-sectional view along the AA direction of Figure 3;
[0043] Figure 6 is an enlarged schematic diagram of part I of Figure 5;
[0044] Figure 7 is a schematic diagram of the structure of the pressing member according to some embodiments of this application;
[0045] Figure 8 is a schematic diagram of the structure of the pressing member according to some embodiments of this application;
[0046] Figure 9 is a structural schematic diagram of the pressing member according to some other embodiments of this application;
[0047] Figure 10 is a structural schematic diagram of the pressing member according to some embodiments of this application.
[0048] Explanation of reference numerals in the attached drawings: 1000, vehicle; 200, battery device; 300, controller; 400, motor; 110, housing; 111, first part; 112, second part; 100, battery cell; 10, casing; 11, enclosure; 111, outer end face; 112, side wall; 113, bottom wall; 12, end cap; 13, receiving space; 14, body; 15, protrusion; 16, groove; 17, pressure relief part; 18, opening; 20, electrode assembly; 30, collector plate; 31, first collector; 32, second collector; 40, pressing member; 41, pressing part; 42, air guiding space; 43, first pressing surface; 44, second pressing surface; 45, groove; 46, connecting part; 47, air guide hole; 48, through hole; 49, weight reduction hole. Detailed Implementation
[0049] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.
[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.
[0051] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.
[0052] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0053] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.
[0054] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).
[0055] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0056] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0057] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing.
[0058] In this application, the battery cell may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application are not limited thereto. The battery cell may be cylindrical, flat, cuboid, or other shapes.
[0059] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack. A battery generally includes a housing for encapsulating one or more battery cells. The housing can reduce the influence of liquids or other foreign matter on the charging or discharging of the battery cells.
[0060] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrodes. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector, and the uncoated current collector protrudes beyond the coated current collector, serving as the positive electrode tab. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector, and the uncoated current collector protrudes beyond the coated current collector, serving as the negative electrode tab. The negative current collector can be made of copper, and the negative active material can be carbon or silicon, etc. To ensure that the membrane does not melt when carrying a large current, there are multiple positive electrode tabs stacked together, and there are multiple negative electrode tabs stacked together. The diaphragm material can be PP (polypropylene) or PE (polyethylene), etc.
[0061] The battery cell also includes a housing, which comprises a perimeter wall and end caps. The perimeter wall has an opening for receiving an electrode assembly, which can be assembled into the perimeter wall through the opening. The end caps are used to close the opening in the perimeter wall to achieve a seal.
[0062] Laser welding is typically used to connect the end cap and the enclosure. Specifically, the current collector is first welded to the negative electrode tab, then the electrode assembly is placed inside the enclosure. The end cap and enclosure are then joined together, and a laser is irradiated at the joint. Under the laser's action, the joint melts and connects. Finally, laser penetration welding is used on the outside of the end cap to the current collector. However, due to the interference fit of the electrode assembly during assembly, when the end cap is installed on the enclosure, it presses against the current collector. Under this pressure, the inner side of the electrode assembly pushes up against the end cap, causing the middle of the current collector to deform and arch towards the end cap, and the edges of the current collector to tilt. This creates a gap between the current collector and the end cap, easily leading to incomplete welds or burn-through in the external welding, reducing the stability of the connection between the current collector and the end cap.
[0063] To improve the stability of the connection between the current collector and the end cover, this application provides a pressing member for a battery cell. The pressing member is located between the end cover and the current collector, which can reduce the clearance space in the explosion-proof valve area, reduce the deformation of the current collector protrusion, and thus reduce the gap between the current collector and the end cover, thereby improving the stability of the connection between the current collector and the end cover.
[0064] The battery cells disclosed in this application can be used, but are not limited to, in electrical equipment such as vehicles, ships, or aircraft. A power system for such electrical equipment can be constructed using battery cells and batteries disclosed in this application.
[0065] This application provides an electrical device that uses a single battery cell as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.
[0066] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.
[0067] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 200 is installed inside the vehicle 1000, and the battery device 200 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 200 can be used to power the vehicle 1000; for example, the battery device 200 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 300 and a motor 400. The controller 300 is used to control the battery device 200 to supply power to the motor 400, for example, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.
[0068] In some embodiments of this application, the battery device 200 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.
[0069] In some embodiments, the battery device 200 may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.
[0070] Please refer to Figure 2, which is an exploded structural diagram of a battery device 200 provided in some embodiments of this application. The battery device 200 includes a battery cell 100 and a housing 110, with the battery cell 100 housed within the housing 110. The housing 110 provides space for the battery cell 100, and the housing 110 can adopt various structures.
[0071] In some embodiments, the housing 110 may include a first portion 111 and a second portion 112, which overlap each other, and together define a receiving space for accommodating the battery cell 100. The second portion 112 may be a hollow structure with one open end, and the first portion 111 may be a plate-like structure, with the first portion 111 covering the open side of the second portion 112 so that the first portion 111 and the second portion 112 together define the receiving space; alternatively, the first portion 111 and the second portion 112 may both be hollow structures with one open side, with the open side of the first portion 111 covering the open side of the second portion 112. Of course, the housing 110 formed by the first portion 111 and the second portion 112 can be of various shapes, such as a cylinder, a cuboid, etc.
[0072] In the battery device 200, there can be multiple battery cells 100, which can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 100 are connected in both series and parallel connections. Multiple battery cells 100 can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 100 is housed within the housing 110. Alternatively, the battery device 200 can also consist of multiple battery cells 100 first connected in series, parallel, or in a mixed configuration to form battery modules, and then these battery modules are connected in series, parallel, or in a mixed configuration to form a whole, which is also housed within the housing 110. The battery device 200 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 100.
[0073] According to some embodiments of this application, please refer to Figures 3-6. Figure 3 is a structural schematic diagram of a battery cell 100 according to some embodiments of this application; Figure 4 is an exploded structural schematic diagram of a battery cell 100 according to some embodiments of this application; Figure 5 is a cross-sectional schematic diagram of Figure 3 along the AA direction; and Figure 6 is an enlarged schematic diagram of part I of Figure 5. The battery cell 100 of this application embodiment includes a housing 10, an electrode assembly 20, a current collector 30, and a pressing member 40. The housing 10 includes a surrounding wall 11 and an end cap 12 connected to the surrounding wall 11. The surrounding wall 11 has a receiving space 13. The end cap 12 includes a body 14 and a protrusion 15 protruding from the body 14. The protrusion 15 is at least partially located in the receiving space 13 and abuts against the inner surface of the surrounding wall 11. The electrode assembly 20 is disposed in the receiving space 13. The current collector 30 is disposed in the receiving space 13 and is located between the end cap 12 and the electrode assembly 20. The pressing member 40 is located between the end cap 12 and the current collector 30. The pressing member 40 includes a pressing part 41 near the protrusion 15. The pressing part 41 and the protrusion 15 together press against the current collector 30. The protrusion 15 is welded to the current collector 30 to form a weld mark.
[0074] Specifically, the enclosure 11 is a hollow structure with an opening 18 at one end, forming an internal space 13 for accommodating the electrode assembly 20 and the electrolyte. The enclosure 11 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, or plastic. The enclosure 11 can also be in various shapes, such as a cylinder or cuboid. The shape of the enclosure 11 can be determined according to the specific shape of the electrode assembly 20. In some embodiments, the battery cell 100 is a cylindrical battery. Correspondingly, the electrode assembly 20 is a cylindrical structure, and the enclosure 11 is a cylindrical hollow structure.
[0075] End cap 12 is a component that seals the opening 18 of enclosure 11 to isolate the internal environment of battery cell 100 from the external environment. End cap 12 and enclosure 11 together define a receiving space 13 for accommodating electrode assembly 20, electrolyte, and other components. The shape of end cap 12 can be adapted to the shape of enclosure 11. For example, if enclosure 11 is a cylindrical structure, end cap 12 can be a circular plate structure adapted to enclosure 11. The material of end cap 12 can also be various, such as copper, iron, aluminum, steel, aluminum alloy, plastic, etc. The materials of end cap 12 and enclosure 11 can be the same or different.
[0076] The body 14 can be a plate-like structure, having an inner surface and an outer surface disposed opposite to each other along its thickness direction, with the inner surface of the body 14 facing the electrode assembly 20. Optionally, both the inner and outer surfaces of the body 14 are planar and parallel. The protrusion 15 protrudes relative to the inner surface of the body 14 in the direction facing the electrode assembly 20, such that at least a portion of the protrusion 15 protrudes beyond the inner surface of the body 14. This embodiment does not limit the degree to which the protrusion 15 protrudes beyond the inner surface of the body 14. The body 14 can entirely surround the outside of the protrusion 15, or it can only partially surround the outside of the protrusion 15. For example, the protrusion 15 can be an annular structure, and the body 14 also has a portion surrounded by the protrusion 15.
[0077] The electrode assembly 20 is the core component for enabling the charging and discharging function of the battery cell 100. The housing 10 may contain one or more electrode assemblies 20. The electrode assembly 20 includes a positive electrode, a negative electrode, and a separator. The positive and negative electrodes have opposite polarities, and the separator is used to insulate and isolate the positive and negative electrodes. The electrode assembly 20 primarily operates by the movement of metal ions between the positive and negative electrodes. Optionally, the positive electrode, negative electrode, and separator are all strip-shaped structures, wound together to form a wound structure.
[0078] The current collector 30 is a component used to draw out the current generated by the electrode assembly 20; therefore, the current collector 30 can be made of a metal material such as copper. The shape of the current collector 30 is similar to that of the end cap 12, thereby improving the compactness of the fit between the current collector 30 and the end cap 12. For example, both the current collector 30 and the end cap 12 can be disc-shaped components.
[0079] The pressing member 40 can be located between the body 14 and the collector plate 30, and the protrusion 15 is located on the outside of the pressing member 40. The surfaces of the pressing part 41 and the protrusion 15 facing the collector plate 30 at least partially press against the collector plate 30. That is, the surface of the pressing part 41 facing the collector plate 30 can partially press against the collector plate 30 or completely press against the collector plate 30; the surface of the protrusion 15 facing the collector plate 30 can partially press against the collector plate 30 or completely press against the collector plate 30.
[0080] In the above embodiment, when assembling the end cover 12, the pressing part 41 and the protrusion 15 jointly press against the collector plate 30, which can reduce the degree of deformation of the collector plate 30, which is beneficial to reduce the gap between the collector plate 30 and the protrusion 15, thereby reducing welding defects between the collector plate 30 and the protrusion 15, and thus improving the stability of the connection between the collector plate 30 and the end cover 12.
[0081] Referring to Figure 6, in some embodiments, the plane of the pressing part 41 facing the collector plate 30 is flush with the plane of the protrusion 15 facing the collector plate 30.
[0082] Specifically, the plane of the pressing part 41 facing the collector plate 30 is flush with the plane of the protrusion 15 facing the collector plate 30, meaning that the plane of the pressing part 41 facing the collector plate 30 and the plane of the protrusion 15 facing the collector plate 30 are on the same plane. The thickness of the pressing part 40 can be the same as the thickness of the protrusion 15 protruding from the body 14.
[0083] In the above embodiment, the plane of the pressing part 41 facing the collector plate 30 is flush with the plane of the protrusion 15 facing the collector plate 30, so that the pressing part 41 and the protrusion 15 can jointly press against the collector plate 30, which helps to reduce the degree of deformation of the collector plate 30, thereby reducing the gap between the collector plate 30 and the protrusion 15.
[0084] Referring to Figure 6, in some embodiments, a groove 16 is formed on the side of the protrusion 15 opposite to the collector plate 30.
[0085] Specifically, the groove 16 is positioned corresponding to the protrusion 15, and the groove 16 is recessed relative to the outer surface of the body 14 in the direction facing the electrode assembly 20. The groove 16 can be formed by removing part of the material from the outer surface of the body 14 corresponding to the groove 16 towards the protrusion 15, and the width of the groove 16 can be smaller than the width of the protrusion 15.
[0086] In some embodiments, the groove 16 and the protrusion 15 are formed by a stamped end cap 12.
[0087] In the above embodiment, the groove 16 can reduce the thickness of the protrusion 15, which can reduce the welding power required to weld the protrusion 15 to the collector plate 30, reduce heat generation, and thus reduce the risk of other components being burned.
[0088] In some embodiments, the groove 16 extends circumferentially along the body 14.
[0089] Specifically, the protrusion 15 can extend circumferentially along the body 14, so that the groove 16 can extend circumferentially along the body 14. The depth and width of the groove 16 can be designed according to actual needs.
[0090] In the above embodiment, the groove 16 extends circumferentially along the body 14, which can reduce the thickness of the protrusion 15 extending circumferentially along the body 14. This can reduce the welding power required to weld the protrusion 15 to the collector plate 30, reduce heat generation, and thus reduce the risk of other components being burned.
[0091] Referring to Figure 6, in some embodiments, the end cap 12 is provided with a pressure relief part 17, and the pressure-blocking part 41 forms an air guiding space 42 corresponding to the pressure relief part 17.
[0092] Specifically, the pressure relief section 17 can be actuated to release internal pressure when the internal pressure of the battery cell 100 reaches a predetermined threshold. The predetermined threshold can be designed according to actual needs. The predetermined threshold may depend on one or more materials of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 100. The pressure relief section 17 can take the form of an explosion-proof valve, a gas valve, a pressure relief valve, or a safety valve, and can specifically adopt a pressure-sensitive element or structure, that is, when the internal pressure of the battery cell 100 reaches the predetermined threshold, the pressure relief section 17 performs an action or a weak structure provided in the pressure relief section 17 ruptures, thereby forming an opening 18 or channel for releasing internal pressure or temperature.
[0093] The term "actuation" as used in this application refers to the activation of the pressure relief section 17, thereby releasing the internal pressure of the battery cell 100. The activation of the pressure relief section 17 may include, but is not limited to, at least a portion thereof rupturing, breaking, tearing, or opening. When the pressure relief section 17 is activated, the high-temperature, high-pressure substances inside the battery cell 100 are discharged outwards from the activated portion. This method allows for pressure relief of the battery cell 100 under controllable pressure, thereby preventing potentially more serious accidents.
[0094] The emissions from the battery cell 100 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.
[0095] The pressure relief part 17 can be integrally formed with the end cap 12. Alternatively, the pressure relief part 17 and the end cap 12 can also be two separate components, which can be connected by welding, riveting, bonding or other means.
[0096] The pressure-retaining portion 41 and the pressure-relieving portion 17 overlap at least partially in the thickness direction. Therefore, if the pressure-retaining portion 41 comes into contact with the pressure-relieving portion 17, the pressure-retaining portion 41 may block the discharge of high-temperature and high-pressure substances when the pressure-relieving portion 17 is actuated, posing a safety risk. In addition, if the pressure-retaining portion 41 and the pressure-relieving portion 17 come into contact, the pressure-retaining portion 41 may easily damage the pressure-relieving portion 17 when the battery cell 100 vibrates, causing the pressure-relieving portion 17 to fail.
[0097] In the above embodiment, a gas guiding space 42 is provided between the pressure-relief part 41 and the pressure-relief part 17, so that gas can reach the pressure-relief part 17 through the gas guiding space 42, thereby reducing the risk of the pressure-relief part 41 damaging the pressure-relief part 17, and allowing gas to be smoothly discharged when the pressure-relief part 17 is actuated, thereby improving the safety performance of the battery cell 100.
[0098] Please refer to Figures 6-8, and Figures 7 and 8 are schematic diagrams of the structure of the pressing member 40 in some embodiments of this application. In some embodiments, the pressing part 41 includes a first pressing surface 43 and a second pressing surface 44 facing away from each other. The first pressing surface 43 abuts against the end cap 12, and the second pressing surface 44 abuts against the collecting plate 30. The air guiding space 42 is a recessed groove 45 extending from the first pressing surface 43 to the second pressing surface 44. The pressing member 40 also includes a connecting part 46 connected to the side of the recessed groove 45. The connecting part 46 is provided with an air guiding hole 47 communicating with the recessed groove 45. The air guiding hole 47 penetrates the connecting part 46 along the thickness direction of the end cap 12.
[0099] Specifically, the first pressing surface 43 and the second pressing surface 44 can be parallel, and the second pressing surface 44 is flush with the plane of the protrusion 15 facing the collector plate 30, so that the second pressing surface 44 and the protrusion 15 can simultaneously abut against the collector plate 30.
[0100] The settling groove 45 can be formed by removing a portion of material from the first pressing surface 43 to the second pressing surface 44 by the pressing member 40. The depth of the settling groove 45 can be less than the thickness of the pressing member 40. The settling groove 45 and the connecting portion 46 are stacked along the thickness direction of the pressing member 40. The plane of the connecting portion 46 near the collecting plate 30 can be flush with the second pressing surface 44, so that the plane of the connecting portion 46 near the collecting plate 30 abuts against the collecting plate 30. The connecting portion 46 and the pressing portion 41 can be integrally formed.
[0101] The air guide hole 47 can be a regular shape such as a circle, square, or polygon, or it can be an irregular shape. The depth of the air guide hole 47 can be equal to the thickness of the connecting part 46.
[0102] In the above embodiment, the venting space 42 formed by the sink 45 can reduce the risk of the pressure relief part 17 being damaged by the pressure-relief part 41. The vent 47 is connected to the sink 45, allowing gas to enter the venting space 42 through the vent 47, which is beneficial for smooth venting when the pressure relief part 17 is actuated, thereby improving the safety performance of the battery cell 100. The connecting part 46 can increase the contact area between the pressure-relief part 40 and the current collector 30, reducing the degree of deformation of the current collector 30.
[0103] Referring to Figure 7, in some embodiments, there are multiple air guide holes 47, which are spaced apart.
[0104] Specifically, the number of air guide holes 47 can be 3, 4, 5, 6 or more. Multiple air guide holes 47 can be arranged in a regular pattern such as rectangles or rings, or they can be arranged irregularly. The diameters of multiple air guide holes 47 can be the same or different.
[0105] In the above embodiment, the multiple vent holes 47 can increase the rate at which gas enters the vent space 42, which is more conducive to smooth exhaust when the pressure relief section 17 is actuated, thereby greatly improving the safety performance of the battery cell 100.
[0106] Please refer to Figures 6 and 9. Figure 9 is a schematic diagram of the structure of the pressing member 40 in some embodiments of this application. In some embodiments, the pressing part 41 includes a first pressing surface 43 and a second pressing surface 44 facing away from each other. The first pressing surface 43 abuts against the end cap 12, the second pressing surface 44 abuts against the collecting plate 30, and the air guiding space 42 is a through hole 48 penetrating the first pressing surface 43 and the second pressing surface 44.
[0107] Specifically, the through hole 48 can be a regular shape such as a circle, square, or polygon, or it can be an irregular shape. The depth of the through hole 48 can be equal to the thickness of the pressing part 41.
[0108] In the above embodiment, the venting space 42 is a through hole 48 that penetrates the first pressure surface 43 and the second pressure surface 44. This can increase the venting space 42, which is beneficial for smooth venting when the pressure relief part 17 is actuated, thereby improving the safety performance of the battery cell 100.
[0109] Please refer to Figure 10, which is a schematic diagram of the structure of the pressing member 40 according to some embodiments of this application. In some embodiments, the wall of the through hole 48 converges from the first pressing surface 43 to the second pressing surface 44.
[0110] Specifically, the wall of the through hole 48 can be an inclined plane, a curved surface, a bent surface, etc. The degree of convergence of the wall of the through hole 48 from the first pressing surface 43 to the second pressing surface 44 can be designed according to actual needs.
[0111] In the above embodiment, the hole wall of the through hole 48 converges from the first pressing surface 43 to the second pressing surface 44, which can increase the area of the second pressing surface 44, thereby increasing the contact area between the pressing part 41 and the collecting plate 30, which helps to reduce the deformation of the collecting plate 30.
[0112] Referring to Figures 6 and 10, in some embodiments, the pressure relief part 41 is provided with a weight reduction hole 49 spaced apart from the air guiding space 42, and the weight reduction hole 49 is located on one side of the pressure relief part 17 along the radial direction of the end cap 12.
[0113] Specifically, the weight-reducing hole 49 can penetrate the pressing part 41 along the thickness direction, that is, the depth of the weight-reducing hole 49 is equal to the thickness of the pressing part 41. The weight-reducing hole 49 can be formed by removing part of the material from the pressing part 41 from the first pressing surface 43 to the second pressing surface 44.
[0114] The weight-reducing holes 49 can be regular shapes such as circles, squares, and polygons, or they can be irregular shapes. There can be multiple weight-reducing holes 49, arranged at intervals along the circumference of the air-guiding space 42. The shapes and diameters of the multiple weight-reducing holes 49 can be the same or different.
[0115] In the above embodiment, the weight reduction hole 49 can reduce the weight of the pressing member 40, while reducing space occupation and facilitating the movement of electrolyte.
[0116] In some embodiments, the pressure relief portion 17 is configured as a pressure relief hole; or, the pressure relief portion 17 is configured as a groove; or, the pressure relief portion 17 is configured as a weakening portion.
[0117] Specifically, the pressure relief section 17 can be configured as a pressure relief hole. When the pressure inside the housing 10 increases due to the exhaust pressure relief of the electrode assembly 20, the gas can flow to the pressure relief hole to exhaust pressure outward.
[0118] The scratches can refer to the indentations or grooves 16 engraved on the end cap 12. When the gas pressure inside the housing 10 is high, the strength of the scratches is weaker than that of other parts of the end cap 12, and the probability of cracking is higher. The gas can break through the scratches to release the gas and relieve pressure.
[0119] The weakened portion can refer to a weaker structure formed on the end cap 12. For example, the weakened portion can be a region on the end cap 12 with reduced thickness, or it can be a structure formed by openings on the end cap 12 and covering it with a thin film. When the gas pressure inside the housing 10 is high, the weakened portion is more likely to rupture, and the gas can break through the location of the weakened portion to release pressure.
[0120] In the above technical solution, by setting the pressure relief part 17 as a pressure relief hole, a groove or a weakening part, more options can be provided for the design of the pressure relief part 17 to meet different usage requirements.
[0121] Referring to Figure 6, in some embodiments, the enclosure 11 forms an opening 18, and the end cap 12 covers the opening 18. The edge of the end cap 12 is welded and fixed to the enclosure 11.
[0122] Specifically, the enclosure 11 includes a side wall 112 and a bottom wall 113 connected to the side wall 112. The side wall 112 extends along the thickness direction and surrounds the outer periphery of the electrode assembly 20, while the bottom wall 113 is disposed perpendicular to the side wall 112.
[0123] The side wall 112 and the bottom wall 113 can be integrally formed, that is, the enclosure 11 is a single integral component. Of course, the side wall 112 and the bottom wall 113 can also be two separate components, which are then connected together by welding, riveting, bonding or other methods.
[0124] One end of the side wall 112 forms an opening 18 in the enclosure 11, and the bottom wall 113 is connected to the other end of the side wall 112 away from the opening 18. The side wall 112 is a cylindrical structure, for example, the side wall 112 is a cylinder; the bottom wall 113 is a circular plate structure.
[0125] The size of the opening 18 can be larger than the size of the electrode assembly 20 so that the electrode assembly 20 can be inserted into the enclosure 11 through the opening 18.
[0126] The diameter of the end cap 12 can be greater than the inner diameter of the enclosure 11 and less than or equal to the outer diameter of the enclosure 11, so that the edge of the end cap 12 can abut against the enclosure 11.
[0127] In the above embodiment, the end cap 12 and the enclosure wall 11 are fixed by welding, which can improve the connection strength between the end cap 12 and the enclosure wall 11. During the welding process, the protrusion 15 can release the welding stress by deformation, thereby reducing the risk of deformation and cracking in the welding area, improving the sealing performance, and thus improving the sealing performance of the battery cell 100.
[0128] Referring to Figure 6, in some embodiments, the enclosure 11 has an outer end face 111 surrounding the opening 18, and the outer end face 111 is welded to the inner surface of the body 14 so that the enclosure 11 and the end cap 12 are connected as one unit.
[0129] Specifically, the outer end face 111 can be located at the outermost end of the enclosure 11, and the inner surface of the body 14 is arranged parallel to the outer end face 111. The inner surface of the body 14 and the outer end face 111 are attached in the thickness direction. During welding, the laser irradiates the junction of the outer end face 111 and the inner surface of the body 14. After welding, at least a portion of the inner surface of the body 14 and at least a portion of the outer end face 111 melt and connect together.
[0130] In the above embodiment, the inner surface of the body 14 abuts against the outer end face 111, which reduces the space occupied by the body 14 in the interior of the enclosure 11. When assembling the end cap 12 and the enclosure 11, the outer end face 111 can serve as an upper limit in the thickness direction of the end cap 12.
[0131] Referring to Figure 6, in some embodiments, the current collector 30 includes a first current collector 31 and a second current collector 32 connected to the first current collector 31. The second current collector 32 surrounds the outside of the first current collector 31. The first current collector 31 is welded to the electrode assembly 20, and the second current collector 32 is welded to the protrusion 15 and forms a solder mark.
[0132] Specifically, the plane of the first current collector 31 facing the electrode assembly 20 can be flush with the plane of the second current collector 32 facing the electrode assembly 20. The surface of the second current collector 32 facing the end cover 12 protrudes from the surface of the first current collector 31 facing the end cover 12. That is to say, the second current collector 32 is closer to the end cover 12 than the first current collector 31, and the second current collector 32 has a ring structure.
[0133] The first current collector 31 can be located between the body 14 and the electrode assembly 20, and the second current collector 32 can be located between the protrusion 15 and the electrode assembly 20. The surface of the second current collector 32 facing the end cap 12 can abut against the protrusion 15 and the second pressing surface 44.
[0134] In the above embodiments, welding can reduce the contact resistance between the first current collector 31 and the electrode assembly 20 and the contact resistance between the second current collector 32 and the protrusion 15, which is beneficial to improving the current carrying capacity.
[0135] Please refer to Figure 2. The battery device 200 of this application embodiment includes a battery cell 100.
[0136] The battery device 200 includes one or more battery cells 100, and the battery device 200 may include a battery module or a battery pack.
[0137] The electrical device according to the embodiments of this application includes a battery cell 100 or a battery device 200. The battery cell 100 or the battery device 200 is used to provide electrical energy to the electrical device.
[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.
Claims
1. A battery cell, wherein, The battery cell includes: A housing, the housing including a wall and an end cap connected to the wall, the wall having a receiving space, the end cap including a body and a protrusion extending from the body, the protrusion being at least partially located in the receiving space, the protrusion abutting against the inner surface of the wall; An electrode assembly disposed within the receiving space; A collector plate, wherein the collector plate is disposed in the receiving space and located between the end cap and the electrode assembly; A pressing member is located between the end cover and the collector plate. The pressing member includes a pressing part near the protrusion. The pressing part and the protrusion together press against the collector plate. The protrusion is welded to the collector plate to form a weld mark.
2. The battery cell according to claim 1, wherein, The plane of the pressing part facing the collector plate is flush with the plane of the protruding part facing the collector plate.
3. The battery cell according to claim 1 or 2, wherein, The protrusion has a groove on the side opposite to the collector plate.
4. The battery cell according to claim 3, wherein, The groove extends circumferentially along the body.
5. The battery cell according to any one of claims 1-4, wherein, The end cap is provided with a pressure relief section, and the pressure-blocking section forms an air guiding space corresponding to the pressure relief section.
6. The battery cell according to claim 5, wherein, The pressing part includes a first pressing surface and a second pressing surface facing away from each other. The first pressing surface abuts against the end cap, and the second pressing surface abuts against the collecting plate. The air guiding space is a recessed groove from the first pressing surface to the second pressing surface. The pressing member also includes a connecting part connected to the side of the settling tank. The connecting part is provided with an air guide hole communicating with the settling tank. The air guide hole passes through the connecting part along the thickness direction of the end cap.
7. The battery cell according to claim 6, wherein, The number of air guide holes is multiple, and the multiple air guide holes are arranged at intervals.
8. The battery cell according to any one of claims 5-7, wherein, The pressure part includes a first pressure surface and a second pressure surface facing away from each other. The first pressure surface abuts against the end cap, and the second pressure surface abuts against the collecting plate. The air guiding space is a through hole that penetrates the first pressure surface and the second pressure surface.
9. The battery cell according to claim 8, wherein, The walls of the through hole converge from the first pressing surface to the second pressing surface.
10. The battery cell according to any one of claims 5-9, wherein, The pressure relief section is provided with a weight reduction hole spaced apart from the air guide space, and the weight reduction hole is located on one side of the pressure relief section along the radial direction of the end cap.
11. The battery cell according to any one of claims 5-9, wherein, The pressure relief section is configured as a pressure relief hole; or, the pressure relief section is configured as a groove; or, the pressure relief section is configured as a weakening section.
12. The battery cell according to any one of claims 1-11, wherein, The enclosure has an opening, the end cap covers the opening, and the edge of the end cap is welded to the enclosure.
13. The battery cell according to claim 12, wherein, The enclosure has an outer end face surrounding the opening, which is welded to the inner surface of the body so that the enclosure and the end cap are connected as one unit.
14. The battery cell according to any one of claims 1-13, wherein, The current collector includes a first current collector and a second current collector connected to the first current collector. The second current collector surrounds the outside of the first current collector. The first current collector is welded to the electrode assembly, and the second current collector is welded to the protrusion to form the solder mark.
15. A battery device, wherein, The battery device comprises the battery cell according to any one of claims 1-14.
16. An electrical appliance, wherein, The electrical equipment includes a battery cell as described in any one of claims 1-14 or a battery device as described in claim 15.