Battery cell, end cap assembly, battery and electric apparatus

Abstract

A battery cell (10), an end cap assembly (100), a battery (13) and an electric apparatus. The battery cell (10) comprises the end cap assembly (100), a casing (200) and an electrode assembly (300). The casing (200) comprises a bottom wall (210) and a side wall (220), which enclose a chamber (A4); the electrode assembly (300) is disposed in the chamber (A4); and the end cap assembly (100) comprises a cover plate (110) and electrode terminals (120) disposed on the cover plate (110), wherein the electrode terminals (120) are connected to the electrode assembly (300), and the cover plate (110) comprises a covering portion (111), which is distributed in a first direction (X), and an insertion portion (112). The covering portion (111) comprises a connecting region (1111) and a surrounding region (1112), wherein the surrounding region (1112) is arranged around the periphery of the connecting region (1111); the insertion portion (112) is disposed in the connecting region (1111), and the insertion portion (112) and the covering portion (111) are connected and enclose each other to form a fitting groove (A1); at least part of the end of the side wall (220) that is away from the bottom wall (210) is connected to the surrounding region (1112) and is inserted into the fitting groove (A1); the insertion portion (112) is inserted into the chamber (A4); and the insertion portion (112) comprises two or more distributed step sections (1121), with cross-sectional areas decreasing section by section, wherein a step groove (A3) is formed between every two adjacent step sections (1121). The influence of the connection of the end cap assembly (100) on the overall thickness of the battery cell (10) can be reduced.

Description

Battery cells, end cap assemblies, batteries, and electrical devices

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese patent application 202420870783.8, filed on April 25, 2024, entitled “Battery cell, end cap assembly, battery and electrical device”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technology, and in particular to a battery cell, end cap assembly, battery, and electrical device. Background Technology

[0004] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development.

[0005] However, in related technologies, the structural design of the end cap assembly of the battery cell is inadequate, which easily damages processing equipment.

[0006] Summary of the Invention

[0007] In view of the above problems, this application provides a battery cell, an end cap assembly, a battery, and an electrical device. The end cap assembly of the battery cell provided in the embodiments of this application is easy to process and does not easily damage the processing equipment.

[0008] In a first aspect, embodiments of this application provide a battery cell, including an end cap assembly, a housing, and an electrode assembly. The housing includes a bottom wall and a side wall, which together form a cavity. The electrode assembly is disposed in the cavity. The end cap assembly includes a cover plate and electrode terminals. The electrode terminals are connected to the electrode assembly. The cover plate includes a covering portion and an insertion portion distributed along a first direction. The covering portion includes a connection area and a surrounding area, which surrounds the outer periphery of the connection area. The insertion portion is disposed in the connection area and is connected to the covering portion, forming a mating groove. The cover plate has an insertion hole. The electrode terminal is disposed in the insertion hole and connected to the cover plate. At least a portion of the side wall away from the bottom wall is connected to the surrounding area and inserted into the mating groove. The insertion portion is inserted into the cavity. Along the first direction and from the covering portion to the insertion portion, the insertion portion includes two or more stepped sections, the cross-sectional area of ​​which gradually decreases, and a stepped groove is formed between each adjacent stepped section.

[0009] The battery cell provided in this application embodiment, through the setting of a cover part and an insertion part, and the insertion part including two or more stepped sections, forms a mating groove between the insertion part and the cover part, and forms a stepped groove between adjacent stepped sections. This allows at least one stepped groove to be made first when manufacturing the end cap assembly of the battery cell, and then the mating groove to be made on the basis of the stepped groove. It is not necessary to make the mating groove directly on the cover plate. Instead, the gradual transition of the stepped groove reduces the probability of damage to the mold that is easy to cause during the process of directly preparing the mating groove on the cover plate, and makes it easier to meet the requirement that the connection of the end cap assembly has little impact on the overall thickness of the battery cell.

[0010] In some embodiments, along a first direction and on one side from the covering portion toward the insertion portion, the thickness of the plurality of stage steps gradually increases.

[0011] The battery cell provided in this application embodiment reduces the difficulty of manufacturing stepped grooves and mating grooves by gradually increasing the thickness of multiple stages. For example, the stepped grooves and mating grooves are manufactured by stamping with a stamping die. As the stamping progresses, the strength and hardness of the cover plate gradually increase, requiring greater external force to manufacture the stepped grooves and mating grooves. This setting allows for the stamping of deeper grooves when the strength and hardness of the cover plate are low, at which point the stamping force of the stamping die is low. As the strength and hardness of the cover plate increase, the groove depth decreases, and the stamping force of the stamping die is also low. This also meets the requirement that the connection of the end cap assembly has little impact on the overall thickness of the battery cell. This setting reduces the difficulty of manufacturing stepped grooves and mating grooves and protects the groove-making die.

[0012] In some embodiments, along the first direction, the maximum thickness dimension of the cover plate is D, and the thickness dimension of the stage farthest from the covered portion is D1, wherein 0.4≤D1 / D≤0.6.

[0013] The battery cell provided in this application embodiment reduces the difficulty of preparing the stepped groove farthest from the cover by limiting the ratio of the maximum thickness of the cover plate to the thickness of the step farthest from the cover portion, and also reduces the difficulty of preparing other stepped grooves and / or mating grooves, thus optimizing the preparation process of the end cap assembly.

[0014] In some embodiments, along the first direction and on the side from the covering portion to the insertion portion, the thickness ratio of two adjacent stage segments ranges from 0.4 to 0.6.

[0015] The battery cell provided in this application optimizes the manufacturing process of the end cap assembly by setting the range of the thickness ratio between two adjacent stages, thereby limiting the range of values ​​for each groove making process and making it highly operable.

[0016] In some embodiments, along the first direction, the thickness dimension of the stage connected to the connecting area is D2, and the thickness dimension of the covering part is D3, wherein 0.25≤D2 / D3≤1.5.

[0017] The battery cell provided in this application embodiment facilitates the preparation of the mating groove by setting the thickness of the stage connected to the connection area and the thickness of the cover, and makes it easy for the mating groove to be installed and positioned on the housing.

[0018] In some embodiments, in a first direction, two adjacent stage stages are provided with a stage stage closer to the cover portion protruding from the outer periphery of a stage stage away from the cover portion, and the protrusion dimension is M, wherein 0.2mm≤M≤5mm.

[0019] The battery cell provided in this application embodiment has a step-like structure in which two adjacent steps are positioned close to the cover portion and protrude from the outer periphery of the step-like stage positioned away from the cover portion. This design allows for high operability in the preparation of stepped grooves, meets the requirements for further preparation of stepped grooves or mating grooves, and ensures that the strength of the end cap assembly is not affected.

[0020] In some embodiments, the cover plate is provided with a plug hole, which extends through the cover portion and each stage along a first direction, and the electrode terminal is disposed in the plug hole and connected to the cover plate.

[0021] The battery cell provided in this application embodiment facilitates the connection between the electrode terminals and the electrode assembly through the insertion hole arranged along the first direction, thereby meeting the connection requirements of both.

[0022] In some embodiments, along a first direction, the surface of the surrounding region away from the connecting region is aligned with the surface of the sidewall away from the chamber.

[0023] The battery cell provided in this application embodiment has a more neat and orderly structure and a more compact structure by aligning the surface of the surrounding area away from the connection area with the surface of the side wall away from the cavity.

[0024] In some embodiments, the minimum vertical distance between the surface of the insertion portion that encloses the mating groove and the surface of the sidewall facing the chamber is d, where 0 mm ≤ d ≤ 0.1 mm.

[0025] The battery cell provided in this application embodiment, by setting the minimum vertical distance between the surface of the insertion part that forms the mating groove and the surface of the side wall facing the cavity, can not only make the end cap assembly better positioned, but also facilitate the connection between the end cap assembly and the housing.

[0026] In some embodiments, a groove is provided on the sidewall. The groove is recessed from the end face of the sidewall away from the bottom wall in a first direction toward the side where the bottom wall is located. The groove penetrates the sidewall toward the inner wall surface of the chamber. At least a portion of the insertion part extends into the groove and abuts against the sidewall.

[0027] The battery cell provided in this application embodiment facilitates the positioning of the insertion part through the setting of the groove, which is conducive to more accurate installation of the end cover assembly. The connection between the side wall of the housing and the cover part is achieved by the mating groove, without affecting the connection between the end cover assembly and the housing.

[0028] Secondly, embodiments of this application provide an end cap assembly, which includes a cover plate and electrode terminals. The cover plate includes a covering portion and an insertion portion distributed along a first direction. The covering portion includes a connecting area and a surrounding area. The surrounding area is disposed around the outer periphery of the connecting area. The insertion portion is disposed in the connecting area. The insertion portion is connected to the covering portion and they surround each other to form a mating groove. The cover plate is provided with a insertion hole. The electrode terminal is disposed in the insertion hole and connected to the cover plate. The insertion portion, along the first direction and pointing from the covering portion to the insertion portion, includes two or more distributed stepped sections, and the cross-sectional area of ​​the two or more stepped sections decreases segment by segment. A stepped groove is formed between each two adjacent stepped sections.

[0029] The end cap assembly provided in this application embodiment, through the setting of a covering part and an insertion part, and the insertion part including two or more stepped sections, forms a mating groove between the insertion part and the covering part, and forms a stepped groove between adjacent stepped sections. This allows at least one stepped groove to be made first when manufacturing the end cap assembly of the battery cell, and then the mating groove to be made on the basis of the stepped groove. It is not necessary to make the mating groove directly on the cover plate. Instead, the gradual transition of the stepped groove reduces the probability of damage to the mold that is easy to cause during the process of directly preparing the mating groove on the cover plate, and makes it easier to meet the requirement that the connection of the end cap assembly has little impact on the overall thickness of the battery cell.

[0030] In some embodiments, along a first direction and on one side from the covering portion toward the insertion portion, the thickness of the plurality of stage steps gradually increases.

[0031] The end cap assembly provided in this application reduces the difficulty of manufacturing stepped grooves and mating grooves by gradually increasing the thickness of multiple stages. For example, the stepped grooves and mating grooves are manufactured by stamping with a stamping die. As stamping progresses, the strength and hardness of the cap plate gradually increase, requiring greater external force to manufacture the stepped grooves and mating grooves. This design allows for the stamping of deeper grooves when the strength and hardness of the cap plate are low, at which point the stamping force of the stamping die is low. As the strength and hardness of the cap plate increase, the groove depth decreases, and the stamping force of the stamping die is also low, thus protecting the groove-making die.

[0032] Thirdly, embodiments of this application provide a battery, including the battery cell of any of the above embodiments.

[0033] The battery provided in this application embodiment facilitates battery manufacturing through the provision of end cap assemblies for individual battery cells, and can mitigate damage to the manufacturing mold during use.

[0034] Fourthly, embodiments of this application provide an electrical device including the battery of any of the above embodiments.

[0035] The electrical device provided in this application embodiment facilitates the preparation and production of the electrical device by setting the end cap assembly of the battery cell, and can reduce the damage rate of the preparation mold during the production process.

[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 following detailed description of preferred embodiments. 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 structural schematic diagram of a vehicle according to an embodiment of this application;

[0039] Figure 2 is a structural schematic diagram of a battery embodiment of this application;

[0040] Figure 3 is an exploded view of a single battery cell according to an embodiment of this application;

[0041] Figure 4 is a structural schematic diagram of an embodiment of the end cap assembly of this application;

[0042] Figure 5 is an enlarged schematic diagram of position A in Figure 4 of this application;

[0043] Figure 6 is a cross-sectional schematic diagram of a portion of the structure of an embodiment of the end cap assembly of this application when used in conjunction with the housing;

[0044] Figure 7 is a cross-sectional schematic diagram of a portion of the structure of another embodiment of the end cap assembly of this application when used in conjunction with the housing.

[0045] The reference numerals in the detailed embodiments are as follows: 1 Vehicle; 11 Motor; 12 Controller; 13 Battery; 10 Battery Cell; 100 End Cap Assembly; X First Direction; 110 Cover Plate; A2 Insertion Hole; 111 Covering Part; 1111 Connection Area; 1112 Surrounding Area; A1 Mating Groove; 112 Insertion Part; 1121 Step; A3 Stepped Groove; 120 Electrode Terminal; 200 Housing; 210 Bottom Wall; 220 Side Wall; 221 Recess; A4 Chamber; 300 Electrode Assembly; 20 Housing. Detailed Implementation

[0046] 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.

[0047] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which the embodiments of this application pertain.

[0048] 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", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0049] Furthermore, technical terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0050] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the 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.

[0051] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0052] 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.

[0053] To facilitate the connection between the end cap assembly of the battery cell and the housing, a deep recess needs to be stamped into the edge of the end cap assembly near the housing. This recess connects to the housing. However, in related technologies, the material of the end cap assembly is often not suitable for stamping into a deep recess, or the end cap assembly is too thick to facilitate stamping into a deep recess, which can easily cause damage to the stamping die or result in the inability to stamp.

[0054] Based on the above considerations, to address the problem that the material of the end cap assembly is often unsuitable for stamping into deep recesses, or that the end cap assembly is too thick to easily be stamped into deep recesses, which can easily cause damage to the stamping die or result in stamping failure, research has found that the above problems can be solved by improving the structure of the end cap assembly of the battery cell. Specifically, a battery cell is proposed, including an end cap assembly, a housing, and an electrode assembly. The housing includes a bottom wall and side walls, which together form a cavity. The electrode assembly is disposed in the cavity. The end cap assembly includes a cover plate and electrode terminals, which are connected to the electrode assembly. The cover plate includes a covering portion and an insertion portion distributed along a first direction. The covering portion includes a connecting area and a surrounding area, which surround the outer periphery of the connecting area. The insertion portion is disposed in the connecting area and is connected to the covering portion, forming a mating groove. At least a portion of the side wall away from the bottom wall is connected to the surrounding area and inserted into the mating groove. The insertion portion is inserted into the cavity. The cover plate is provided with a plug hole and an electrode terminal is provided in the plug hole and connected to the cover plate. The insertion part includes two or more distributed stepped sections along the first direction and from the covering part to the insertion part. The cross-sectional area of ​​the two or more stepped sections decreases segment by segment, and a stepped groove is formed between each two adjacent stepped sections.

[0055] The battery cell provided in this application embodiment, through the arrangement of a cover portion and an insertion portion, wherein the insertion portion includes two or more stepped sections, and the insertion portion and the cover portion enclose to form a mating groove, and the adjacent stepped sections enclose to form a stepped groove, allows at least one stepped groove to be made first when manufacturing the end cap assembly of the battery cell, and then the mating groove to be made on the basis of the stepped groove. It is not necessary to make the mating groove directly on the cover plate, but to make the mating groove through the gradual transition of the stepped groove, and then make the mating groove on the basis of the stepped groove. Therefore, it reduces the probability of damage to the mold for making the groove during the process of making the mating groove directly on the cover plate, and makes it easier to meet the requirement that the connection of the end cap assembly has little impact on the overall thickness of the battery cell.

[0056] Battery cells can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft.

[0057] This application provides an electrical device that uses a battery 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.

[0058] For ease of explanation, the following embodiments will be described using a vehicle as an example of an electrical device according to an embodiment of this application.

[0059] Please refer to Figure 1, which is a structural schematic diagram of a vehicle embodiment of this application. Vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc. A battery 13 is installed inside vehicle 1, and the battery 13 can be located at the bottom, front, or rear of vehicle 1. The battery 13 can be used to power vehicle 1; for example, the battery 13 can serve as the operating power source for vehicle 1. Vehicle 1 may also include a controller 12 and a motor 11. The controller 12 is used to control the battery 13 to supply power to the motor 11, for example, to meet the power needs of vehicle 1 during starting, navigation, and driving.

[0060] Please refer to Figure 2, which is a structural schematic diagram of an embodiment of the battery 13 of this application. In some embodiments of this application, the battery 13 can not only serve as the operating power source of the vehicle 1, but also as the driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0061] The battery 13 mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells 10 to provide higher voltage and capacity. When there are multiple battery cells 10, the multiple battery cells 10 are connected in series, parallel, or mixed via a busbar.

[0062] In some embodiments, the battery 13 can be a battery module; when there are multiple battery cells 10, the multiple battery cells 10 are arranged and fixed to form a battery module.

[0063] In some embodiments, the battery 13 may be a battery pack, which includes a housing 20 and battery cells 10, wherein the battery cells 10 or battery modules are housed in the housing 20.

[0064] In some embodiments, the housing 20 may be part of the chassis structure of the vehicle 1. For example, a portion of the housing 20 may be at least a portion of the floor of the vehicle 1, or a portion of the housing 20 may be at least a portion of the crossbeams and longitudinal beams of the vehicle 1.

[0065] In some embodiments, the battery 13 may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0066] Please refer to Figure 3, which is an exploded view of an embodiment of the battery cell 10 of this application. In this embodiment, the battery cell 10 can be a secondary battery cell 10, which refers to a battery cell 10 that can be used again after being discharged by recharging to activate the active material.

[0067] A battery cell 10 typically includes an electrode assembly 300. The electrode assembly 300 includes a positive electrode and a negative electrode. During the charging and discharging process of the battery cell 10, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes.

[0068] In some embodiments, the electrode assembly 300 further includes an isolator disposed between the positive and negative electrodes, which can prevent short circuits between the positive and negative electrodes while allowing active ions to pass through.

[0069] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a layer of positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0070] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0071] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, stainless steel, copper, aluminum, nickel, silver-coated aluminum, silver-coated stainless steel, carbon electrodes, carbon, nickel, or titanium can be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0072] In some embodiments, the positive electrode can be made of foamed carbon or foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or lithium-rich material.

[0073] In some embodiments, the negative electrode may be a negative electrode sheet, which may include a negative electrode current collector and a layer of negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0074] As an example, the negative electrode current collector can be a metal foil, foamed metal, foamed carbon, or a composite current collector. For example, as a metal foil, stainless steel, copper, aluminum, nickel, silver-treated aluminum, silver-treated stainless steel, carbon electrodes, carbon, nickel, or titanium can be used. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloys. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0075] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cell 10. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for battery 13 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0076] In some embodiments, the negative electrode can be made of foamed carbon or foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloy, etc. When foamed metal is used as the negative electrode sheet, the surface of the foamed metal may or may not have a negative electrode active material.

[0077] As an example, lithium source material, potassium metal or sodium metal may also be filled or deposited in the negative electrode current collector, wherein the lithium source material is lithium metal and / or lithium-rich material.

[0078] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0079] In some embodiments, the separator is a diaphragm. This application does not impose any particular limitation on the type of diaphragm; any known porous diaphragm with good chemical and mechanical stability can be selected.

[0080] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0081] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrode plates, serving both to transport ions and to isolate the positive and negative electrodes.

[0082] In some embodiments, the electrode assembly 300 is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0083] In some embodiments, the electrode assembly 300 may be cylindrical, flat, or polygonal in shape.

[0084] In some embodiments, the electrode assembly 300 is provided with tabs that can conduct current from the electrode assembly 300. The tabs include a positive tab and a negative tab.

[0085] In some embodiments, the battery cell 10 includes a housing 200, and the electrode assembly 300 is located in the housing 200.

[0086] In some embodiments, the battery cell 10 further includes an end cap assembly 100, which is a component that covers the opening of the housing 200 to isolate the internal environment of the battery cell 10 from the external environment. Indiscriminately, the shape of the end cap assembly 100 can be adapted to the shape of the housing 200 to fit the housing 200. Optionally, the end cap assembly 100 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap assembly 100 is not easily deformed under compression and impact, enabling the battery cell 10 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 120 can be provided on the end cap assembly 100. The electrode terminals 120 can be used for electrical connection with the electrode assembly 300 to output or input electrical energy from the battery cell 10.

[0087] In some embodiments, the end cap assembly 100 may also be provided with a pressure relief component for releasing internal pressure when the internal pressure or temperature of the battery cell 10 reaches a threshold. The end cap assembly 100 may also be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this.

[0088] Please refer to Figures 4 to 7. Figure 4 is a structural schematic diagram of an embodiment of the end cap assembly 100 of this application. Figure 5 is an enlarged schematic diagram of position A in Figure 4 of this application. Figure 6 is a cross-sectional schematic diagram of a portion of the structure of an embodiment of the end cap assembly 100 of this application when used in conjunction with the housing 200. Figure 7 is a cross-sectional schematic diagram of a portion of the structure of another embodiment of the end cap assembly 100 of this application when used in conjunction with the housing 200.

[0089] This application provides an end cap assembly 100, which includes a cover plate 110 and an electrode terminal 120. The cover plate 110 includes a covering portion 111 and an insertion portion 112 distributed along a first direction X. The covering portion 111 includes a connecting area 1111 and a surrounding area 1112. The surrounding area 1112 is disposed around the outer periphery of the connecting area 1111. The insertion portion 112 is disposed in the connecting area 1111. The insertion portion 112 is connected to the covering portion 111 and they surround each other to form a mating groove A1. The cover plate 110 is provided with a insertion hole A2. The electrode terminal 120 is disposed in the insertion hole A2 and connected to the cover plate 110. The insertion portion 112 includes two or more stepped sections 1121 distributed along the first direction X and pointing from the covering portion 111 to the insertion portion 112. The cross-sectional area of ​​the two or more stepped sections 1121 decreases segment by segment. A stepped groove A3 is formed between each two adjacent stepped sections 1121.

[0090] The covering portion 111 of the cover plate 110 includes, but is not limited to, a columnar structure, a rounded rectangular structure, etc. The material of the cover plate 110 includes, but is not limited to, aluminum, steel, etc. The shape of the mating groove A1 includes, but is not limited to, an L-shaped groove, a U-shaped groove, etc. The mating groove A1 is used to mate and connect with the housing 200 of the battery cell 10.

[0091] The number of stages 1121 of the insertion part 112 may include two, three, etc.

[0092] Along the first direction X, the thickness of the stepped groove A3 may or may not be the same as the thickness of the mating groove A1. When there are two stage 1121s, there is one stepped groove A3; when there are N stage 1121s, there are N-1 stepped grooves A3.

[0093] Optionally, the first direction X is the thickness direction of the cover plate 110.

[0094] Optionally, the cover plate 110 is an integral structure, and the stepped groove A3 and the mating groove A1 are formed by stamping the cover plate 110 multiple times.

[0095] Optionally, the stepped groove A3 and the mating groove A1 are both made by stamping dies.

[0096] The end cap assembly 100 provided in this application embodiment, through the arrangement of a covering part 111 and an insertion part 112, wherein the insertion part 112 includes two or more stepped sections 1121, and the insertion part 112 and the covering part 111 enclose to form a mating groove A1, and the adjacent stepped sections 1121 enclose to form a stepped groove A3, allows at least one stepped groove A3 to be made first during the manufacturing of the end cap assembly 100, and the mating groove A1 to be made on the basis of the stepped groove A3. It is not necessary to directly make the mating groove A1 on the cover plate 110, but through the gradual transition of the stepped groove A3, thus reducing the probability of damage to the mold for making the groove during the process of directly preparing the mating groove A1 on the cover plate 110, and making it easier to meet the requirement that the connection of the end cap assembly 100 has little impact on the overall thickness of the battery cell 10.

[0097] In some embodiments, along the first direction X and on the side from the cover portion 111 to the insertion portion 112, the thickness of the plurality of stage 1121 gradually increases.

[0098] Along the first direction X and from the side of the covering part 111 pointing to the insertion part 112, the thickness increment of the stage 1121 gradually increases according to the actual situation.

[0099] It is understandable that the thickness of the stage 1121 is the same as the depth of the stepped groove A3 along the first direction X and the depth of the mating groove A1 along the first direction X.

[0100] The end cap assembly 100 provided in this application embodiment reduces the manufacturing difficulty of the stepped groove A3 and the mating groove A1 by gradually increasing the thickness of multiple stages 1121. For example, the stepped groove A3 and the mating groove A1 are manufactured by stamping with a stamping die. As the stamping progresses, the strength and hardness of the cover plate 110 gradually increase, requiring greater external force to manufacture the stepped groove A3 and the mating groove A1. The above setting allows for the stamping of deeper grooves when the strength and hardness of the cover plate 110 are low, at which point the stamping force of the stamping die is low. As the strength and hardness of the cover plate 110 increase, the groove depth decreases, and the stamping force of the stamping die is also low. This also meets the requirement that the connection of the end cap assembly 100 has little impact on the overall thickness of the battery cell 10. The above setting reduces the manufacturing difficulty of the stepped groove A3 and the mating groove A1 and protects the groove-making die, reducing wear on the groove-making die.

[0101] In some embodiments, along the first direction X, the maximum thickness dimension of the cover plate 110 is D, and the thickness dimension of the stage 1121 farthest from the covering portion 111 is D1, wherein 0.4≤D1 / D≤0.6.

[0102] When D1 / D is less than 0.4, the stepped groove A3, which is farthest from the covering part 111, is easy to prepare, but it will increase the difficulty of preparing other grooves and increase the difficulty of the groove making process; when D1 / D is greater than 0.6, it may reduce the strength of the cover plate 110.

[0103] The values ​​of D1 / D include 0.4, 0.5, and 0.6. When the value of D1 / D is 0.4, the fabrication of other grooves is relatively easy, and the fabrication of the stepped groove A3, which is farthest from the covering part 111, is also relatively easy. When the value of D1 / D is 0.5, the fabrication of other grooves is relatively easy, and the fabrication of the stepped groove A3, which is farthest from the covering part 111, is also relatively easy. When the value of D1 / D is 0.6, the fabrication of other grooves is relatively easy, and the fabrication of the stepped groove A3, which is farthest from the covering part 111, is also relatively easy.

[0104] Optionally, 0.45 ≤ D1 / D ≤ 0.55.

[0105] The end cap assembly 100 provided in this application embodiment reduces the difficulty of manufacturing the stepped groove A3 furthest from the covering portion 111 by limiting the ratio of the maximum thickness dimension of the cover plate 110 to the thickness dimension of the step 1121 furthest from the covering portion 111, and also reduces the difficulty of manufacturing other stepped grooves A3 and / or mating grooves A1, thus optimizing the manufacturing process of the end cap assembly 100.

[0106] In some embodiments, along the first direction X and on the side from the cover portion 111 to the insertion portion 112, the thickness ratio of two adjacent stage 1121 ranges from 0.4 to 0.6.

[0107] The thickness ratio of two adjacent stage 1121 can range from 0.4, 0.5, to 0.6. When the thickness ratio of two adjacent stage 1121 is 0.4, the number of prepared grooves will not be too large, but the complexity of the preparation process will increase. When the thickness ratio of two adjacent stage 1121 is 0.5, the difficulty of preparing each groove is low, and the process is simple. When the thickness ratio of two adjacent stage 1121 is 0.6, the number of prepared grooves is small, the difficulty of preparing each groove is low, and it will not have an adverse effect on the groove-making mold.

[0108] Optionally, the thickness ratio of two adjacent stage 1121 can range from 0.45 to 0.55.

[0109] The end cap assembly 100 provided in this application embodiment optimizes the manufacturing process of the end cap assembly 100 by setting the range of the thickness ratio of two adjacent stage 1121, thereby limiting the range of values ​​for each groove making and making it highly operable.

[0110] In some embodiments, along the first direction X, the thickness dimension of the stage 1121 connected to the connection area 1111 is D2, and the thickness dimension of the covering portion 111 is D3, wherein 0.25≤D2 / D3≤1.5.

[0111] The values ​​of D2 / D3 include 0.25, 0.5, 1.0, 1.25, and 1.5. When the value of D2 / D3 is 0.25, the preparation of the mating groove A1 is easy, and the connection between the mating groove A1 and the housing 200 will not be affected by the shallow depth of the mating groove A1 along the first direction X. When the value of D2 / D3 is 1.0, the preparation of the mating groove A1 is simple, and the installation and positioning effect of the housing 200 is good. When the value of D2 / D3 is 1.5, it will not have an adverse effect on the connection strength of the surrounding area 1112, and it meets the requirements of the overall height of the end cap assembly 100 and the housing 200 assembly.

[0112] Optionally, 0.5 ≤ D2 / D3 ≤ 1.

[0113] The end cap assembly 100 provided in this application embodiment facilitates the preparation of the mating groove A1 by setting the thickness of the stage 1121 connected to the connecting area 1111 and the thickness of the covering part 111, and makes it easy for the mating groove A1 to install and position the housing 200.

[0114] In some embodiments, in the first direction X, two adjacent stage stages 1121 are provided near the cover portion 111 and protrude from the outer periphery of the stage stage 1121 located away from the cover portion 111, with a protrusion dimension of M, wherein 0.2mm≤M≤5mm.

[0115] If the value of M is less than 0.2 mm, the stamping difficulty of the adjacent mating groove A1 and / or stepped groove A3 will increase due to the small size of M. If the value of M is greater than 5 mm, it will have an adverse effect on the strength of the end cap assembly 100.

[0116] The value of M ranges from 0.2mm, 1mm, 2mm, 3mm, 4mm, to 5mm. When M is 0.2mm, it is easy to prepare the mating groove A1 or the stepped groove A3 based on the stepped groove A3, and the end cap assembly 100 can be guaranteed to have greater strength. When M is 3mm, the stress is more even when preparing the stepped groove A3, the shape of the stepped groove A3 is more regular, and the strength of the end cap assembly 100 is greater. When M is 5mm, it is easy to prepare the stepped groove A3, and it will not have an adverse effect on the strength of the end cap assembly 100.

[0117] Optionally, 2mm ≤ M ≤ 4mm.

[0118] The end cap assembly 100 provided in this application embodiment has a protrusion size of two adjacent stepped stages 1121 that are close to the covering part 111 and protrude from the outer periphery of the stepped stages 1121 that are far from the covering part 111. This makes it highly operable when preparing the stepped groove A3, meets the requirements for further preparing the stepped groove A3 or the mating groove A1, and ensures that the strength of the end cap assembly 100 is not affected.

[0119] In some embodiments, the insertion hole A2 is disposed along the first direction X through the cover portion 111 and each stage 1121.

[0120] Optionally, the number of sockets A2 includes two.

[0121] The end cap assembly 100 provided in this application embodiment facilitates the connection between the electrode terminal 120 and the electrode assembly 300 through the insertion hole A2 along the first direction X, thereby meeting the connection requirements of both.

[0122] This application provides an end cap assembly 100, which includes a cover plate 110 and electrode terminals 120. The cover plate 110 includes a covering portion 111 and an insertion portion 112 distributed along the first direction X. The covering portion 111 includes a connecting area 1111 and a surrounding area 1112. The surrounding area 1112 is disposed around the outer periphery of the connecting area 1111. The insertion portion 112 is disposed in the connecting area 1111. The insertion portion 112 is connected to the covering portion 111 and they surround each other to form a mating groove A1. The cover plate 110 is provided with a insertion hole A2. The orthographic projection of the covering portion 111 along the first direction X is a rounded rectangle. The thickness of the covering portion 111 along the first direction X is 0.5mm to 1mm. The insertion portion 112 is located along the first direction X and points from the covering portion 111 to the insertion portion 112. The insertion portion 112 includes two stepped sections 1121, and the cross-sectional area of ​​the two or more stepped sections 1121 gradually decreases. A stepped groove A3 is formed between each two adjacent stepped sections 1121. Along the first direction X, from the side of the covering portion 111 towards the insertion portion 112, the thickness of the plurality of stage steps 1121 gradually increases. Along the first direction X, from the side of the covering portion 111 towards the insertion portion 112, the ratio of the thickness of two adjacent stage steps 1121 ranges from 0.4 to 0.6. Along the first direction X, the thickness of the stage step 1121 connected to the connecting area 1111 is D2, and the thickness of the covering portion 111 is D3, where 0.25 ≤ D2 / D3 ≤ 1.5. In the first direction X, the stage step 1121 located near the covering portion 111 protrudes from the outer periphery of the stage step 1121 located away from the covering portion 111, and the protrusion dimension is from 0.2 mm to 5 mm.

[0123] This application provides a battery cell 10, which includes a housing 200, an electrode assembly 300, and an end cap assembly 100 as described in any of the above embodiments. The housing 200 includes a bottom wall 210 and a side wall 220, which together form a cavity A4. The electrode assembly 300 is disposed in the cavity A4. At least a portion of the side wall 220 away from the bottom wall 210 is connected to a surrounding area 1112 and inserted into a mating groove A1. An insertion portion 112 is inserted into the cavity A4. An electrode terminal 120 is connected to the electrode assembly 300.

[0124] At least a portion of the sidewall 220 at the end away from the bottom wall 210 is inserted into the mating groove A1, including at least a small portion or all of it. The connection between the sidewall 220 and the surrounding area 1112 includes welding, bonding, etc.

[0125] The battery cell 10 provided in this application embodiment, through the setting of the end cap assembly 100, can not only meet the requirement that the sum of the thickness of the housing 200 of the battery cell 10 along the first direction X and the thickness of the end cap assembly 100 is within a preset range, but also set the thickness of other positions of the end cap assembly 100 to be adjusted according to the actual situation to meet the strength requirements of the end cap assembly 100, and facilitate the preparation of the end cap assembly 100, further facilitating the preparation of the battery cell 10.

[0126] In some embodiments, along the first direction X, the surface of the surrounding region 1112 facing away from the connecting region 1111 is aligned with the surface of the sidewall 220 away from the chamber A4.

[0127] Alignment setting refers to the fact that, along the first direction X, the orthographic projection of the surface of the surrounding area 1112 facing away from the connecting area 1111 completely coincides with the orthographic projection of the surface of the side wall 220 away from the chamber A4.

[0128] The battery cell 10 provided in this application embodiment has a more neat and orderly structure and a more compact structure because the surface of the surrounding region 1112 away from the connection region 1111 is aligned with the surface of the side wall 220 away from the chamber A4.

[0129] In some embodiments, the minimum vertical distance between the surface of the insertion part 112 that encloses the mating groove A1 and the surface of the side wall 220 facing the chamber A4 is d, where 0mm≤d≤0.1mm.

[0130] If the value of d is greater than 0.1 mm, the distance between the surface of the insertion part 112 that forms the mating groove A1 and the surface of the side wall 220 facing the chamber A4 will be too large, which will affect the assembly accuracy of the housing 200 and the mating groove A1, and reduce the compactness of the battery cell 10.

[0131] The value of d ranges from 0mm, 0.05mm, to 0.1mm. When the value of d is 0mm, there is no gap after the housing 200 and the mating groove A1 are assembled, resulting in a compact structure. When the value of d is 0.05mm, the assembly of the housing 200 and the mating groove A1 is easy to operate and will not affect the connection between the two. When the value of d is 0.1mm, it is easy to insert the mating groove A1 of the end cap assembly 100 into the side wall 220 of the housing 200.

[0132] The battery cell 10 provided in this application embodiment has a minimum vertical distance between the surface of the insertion part 112 that forms the mating groove A1 and the surface of the side wall 220 facing the chamber A4. This allows for better positioning of the end cap assembly 100 and facilitates the connection between the end cap assembly 100 and the housing 200.

[0133] In some embodiments, a groove 221 is provided on the sidewall 220. The groove 221 is recessed from the end face of the sidewall 220 away from the bottom wall 210 in the first direction X toward the side where the bottom wall 210 is located. The groove 221 penetrates the inner wall surface of the sidewall 220 toward the chamber A4. At least a portion of the insertion part 112 extends into the groove 221 and abuts against the sidewall 220.

[0134] The battery cell 10 provided in this application embodiment facilitates the positioning of the insertion part 112 through the setting of the groove 221, which is conducive to more accurate installation of the end cover assembly 100. The side wall 220 of the housing 200 and the cover part 111 are connected in the mating groove A1, without affecting the connection between the end cover assembly 100 and the housing 200.

[0135] This application provides a battery 13, which includes the battery cell 10 of any of the above embodiments.

[0136] The battery 13 provided in this application embodiment, through the setting of the end cap assembly 100 of the battery cell 10, facilitates the preparation of the battery 13 and can prevent damage during the use of the mold.

[0137] This application provides an electrical device including the battery 13 of any of the above embodiments.

[0138] The electrical device provided in this application embodiment facilitates the preparation and production of the electrical device by setting the end cap assembly 100 of the battery cell 10, and can reduce the damage rate of the preparation mold during the production process.

[0139] 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 single battery cell, comprising: The shell includes a bottom wall and side walls, wherein the side walls and the bottom wall enclose a cavity; Electrode assemblies are disposed in the chamber; An end cap assembly includes a cover plate and electrode terminals disposed on the cover plate. The electrode terminals are connected to the electrode assembly. The cover plate includes a covering portion and an insertion portion distributed along a first direction. The covering portion includes a connecting area and a surrounding area. The surrounding area surrounds the outer periphery of the connecting area. The insertion portion is disposed in the connecting area. The insertion portion is connected to the covering portion and they enclose each other to form a mating groove. At least a portion of the sidewall away from the bottom wall is connected to the surrounding area and inserted into the mating groove. The insertion portion is inserted into the cavity. Along the first direction and on the side from the covering portion toward the insertion portion, the insertion portion includes two or more distributed stepped sections, and the cross-sectional area of ​​the two or more stepped sections decreases segment by segment, with a stepped groove formed between each two adjacent stepped sections.

2. The battery cell according to claim 1, wherein, Along the first direction and from the side of the covering portion toward the insertion portion, the thickness of the plurality of stage phases gradually increases.

3. The battery cell according to claim 1, wherein, Along the first direction, the maximum thickness dimension of the cover plate is D, and the thickness dimension of the stage farthest from the covering part is D1, wherein 0.4≤D1 / D≤0.

6.

4. The battery cell according to claim 1, wherein, Along the first direction and from the side of the covering portion toward the insertion portion, the thickness ratio of two adjacent stage segments ranges from 0.4 to 0.

6.

5. The battery cell according to claim 1, wherein, Along the first direction, the thickness dimension of the stage connected to the connecting area is D2, and the thickness dimension of the covering part is D3, wherein 0.25≤D2 / D3≤1.

5.

6. The battery cell according to claim 1, wherein, In the first direction, the stage near the cover portion of two adjacent stage segments protrudes from the outer periphery of the stage segment away from the cover portion, and the protrusion dimension is M, where 0.2mm≤M≤5mm.

7. The battery cell according to any one of claims 1 to 6, wherein, The cover plate is provided with a plug hole, which is provided through the cover portion and each of the stage steps along the first direction. The electrode terminal is provided in the plug hole and connected to the cover plate.

8. The battery cell according to claim 1, wherein, Along the first direction, the surface of the surrounding area opposite to the connecting area is aligned with the surface of the sidewall away from the chamber.

9. The battery cell according to claim 1, wherein, The minimum vertical distance between the surface of the insertion part that encloses the mating groove and the surface of the side wall facing the chamber is d, where 0 mm ≤ d ≤ 0.1mm.

10. The battery cell according to claim 1, wherein, A groove is provided on the side wall. The groove is recessed from the end face of the side wall away from the bottom wall in the first direction toward the side where the bottom wall is located. The groove penetrates the side wall toward the inner wall surface of the chamber. At least a portion of the insertion part extends into the groove and abuts against the side wall.

11. An end cap assembly, comprising: A cover plate includes a covering portion and an insertion portion distributed along a first direction. The covering portion includes a connecting area and a surrounding area. The surrounding area is arranged around the outer periphery of the connecting area. The insertion portion is disposed in the connecting area. The insertion portion is connected to the covering portion and they surround each other to form a mating groove. The cover plate is provided with a plug hole. Electrode terminals are disposed in the insertion hole and connected to the cover plate; Along the first direction and on the side from the covering portion toward the insertion portion, the insertion portion includes two or more distributed stepped sections, and the cross-sectional area of ​​the two or more stepped sections decreases segment by segment, with a stepped groove formed between each two adjacent stepped sections.

12. The end cap assembly according to claim 11, wherein, Along the first direction and from the side of the covering portion toward the insertion portion, the thickness of the plurality of stage phases gradually increases.

13. A battery comprising a battery cell according to any one of claims 1 to 10.

14. An electrical device comprising the battery of claim 13.

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