Battery cell, battery, electrical equipment, and method and equipment for manufacturing battery cell

Abstract

The embodiments of the present application provide a battery cell, a battery, an electrical device, and a method and equipment for manufacturing a battery cell, which belongs to the field of battery technology. The battery cell includes an electrode assembly, a shell, and an end cap. The electrode assembly has a first pole lug. The shell has an opening and a first limiting portion, and the shell is used to accommodate the electrode assembly. The end cap includes a cover body, the cover body is used to cover the opening, and in the thickness direction of the end cap, the cover body is located on the side of the first limiting portion away from the electrode assembly, and the first limiting portion is used to limit the movement of the cover body relative to the shell in the direction facing the electrode assembly. The end cap also includes a first protrusion protruding from the inner surface of the cover body in the direction facing the electrode assembly, and the first protrusion is configured to exceed the first limiting portion in the direction away from the cover body, so that the first protrusion presses against the first pole lug, ensuring good contact between the first protrusion and the first pole lug, reducing the risk of the first pole lug being unable to contact the end cap due to the limitation of the first limiting portion, and ensuring battery performance.

Description

Technical Field

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

[0002] Batteries are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric airplanes, electric boats, electric toy cars, electric toy boats, electric toy airplanes and power tools, etc.

[0003] A battery cell typically consists of a housing, an electrode assembly, and an end cap. The electrode assembly is housed within the housing, and the end cap fits over one end opening of the housing. The end cap is electrically connected to the tab, serving as the output terminal of the battery cell. For typical battery cells, due to structural limitations of the housing, the end cap and tab may not make contact or have poor contact, impacting normal battery cell operation. Summary of the Invention

[0004] The embodiments of the present application provide a battery cell, a battery, an electrical device, and a method and device for manufacturing the battery cell, which can ensure good contact between the end cap and the tab in the battery cell.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, comprising: an electrode assembly having a first tab; a shell having an opening and a first limiting portion, the shell being used to accommodate the electrode assembly; an end cover comprising a cover body, the cover body being used to cover the opening, and in the thickness direction of the end cover, the cover body is located on the side of the first limiting portion away from the electrode assembly, the first limiting portion being used to limit the movement of the cover body relative to the shell in a direction facing the electrode assembly; the end cover also includes a first protrusion protruding from the inner surface of the cover body in a direction facing the electrode assembly, the first protrusion being configured to exceed the first limiting portion in a direction away from the cover body so that the first protrusion is pressed against the first tab.

[0006] In the above technical solution, the first protrusion of the end cover extends beyond the first limiting portion in a direction away from the cover body, so that the protrusion is pressed against the first pole ear, ensuring good contact between the first protrusion and the first pole ear, increasing the flow area between the first pole ear and the end cover, reducing the risk of the first pole ear being unable to contact the end cover due to being restricted by the first limiting portion of the shell, and ensuring battery performance.

[0007] In some embodiments, in the thickness direction, the first protrusion has a contact plane against the first electrode tab, and the contact plane is closer to the electrode assembly as a whole than the first limiting portion.

[0008] In the above technical solution, the abutment plane of the first protrusion abuts against the first electrode tab, increasing the contact area between the first electrode tab and the first protrusion, thereby increasing the flow area between the first electrode tab and the end cap. The abutment plane is closer to the electrode assembly than the first stopper, allowing the first protrusion to extend beyond the first stopper in a direction away from the cover body.

[0009] In some embodiments, the battery cell further includes: a first insulating member for isolating the cover body from the shell to achieve an insulating connection between the cover body and the shell.

[0010] In the above technical solution, the first insulating member serves to isolate the cover body from the shell, so that the cover body and the shell are insulated.

[0011] In some embodiments, the first insulating member includes: an insulating portion for isolating the cover body from the housing; and a pressing portion connected to the insulating portion for pressing against the first tab.

[0012] In the above technical solution, the first insulating member includes an insulating portion and a pressing portion connected to the insulating portion. The insulating portion isolates the cover body from the housing to achieve an insulated connection between the cover body and the housing. The pressing portion presses against the first tab, restraining it and reducing the risk of the first tab tilting and contacting the first limiting portion, which could cause a positive-negative short circuit. In other words, the first insulating member not only provides insulation between the cover body and the housing, but also restrains the first tab.

[0013] In some embodiments, in the thickness direction, the pressing portion extends from the insulating portion in a direction facing the electrode tab to press against the first electrode tab.

[0014] In the above technical solution, the pressing portion extends from the insulating portion in the thickness direction of the end cover in the direction facing the tab, so that the pressing portion has a better pressing effect on the first tab, and the first tab is less likely to curl up.

[0015] In some embodiments, the pressing portion is located at an outer periphery of the first protrusion, and the first limiting portion is located at an outer periphery of the pressing portion, and the pressing portion is used to isolate the first protrusion and the first limiting portion.

[0016] In the above technical solution, the pressing portion is located on the outer periphery of the first protrusion, and the first limiting portion is located on the outer periphery of the pressing portion, that is, the pressing portion is located between the first protrusion and the first limiting portion, so that the pressing portion plays a role in isolating the first protrusion and the first limiting portion, reducing the risk of contact between the first protrusion and the first limiting portion.

[0017] In some embodiments, the pressing portion is an annular structure.

[0018] In the above technical solution, the pressing portion is an annular structure, which can press the first electrode tab all around, thereby providing a better restriction on the first electrode tab.

[0019] In some embodiments, the cover body is sealed and connected to the housing through the first insulating member.

[0020] In the above technical solution, the cover body is sealed with the housing through the first insulating member, and the first insulating member plays both an insulating and sealing role between the cover body and the housing.

[0021] In some embodiments, the shell further has a second limiting portion; in the thickness direction, the cover body is located on the side of the second limiting portion facing the electrode assembly, and the second limiting portion and the first limiting portion are used to jointly limit the movement of the cover body relative to the shell along the thickness direction.

[0022] In the above technical solution, the second and first limiting portions of the housing both limit the cover body, thereby cooperating to restrict movement of the cover body relative to the housing in the thickness direction of the end cap. The first limiting portion restricts movement of the cover body relative to the housing in a direction toward the electrode assembly, while the second limiting portion restricts movement of the cover body relative to the housing in a direction away from the electrode assembly.

[0023] In some embodiments, the second limiting portion is a flange structure formed by partially folding the shell inward and at the opening position.

[0024] In the above technical solution, the second limiting portion is a flange structure formed by partially folding the shell inward and at the opening position. That is to say, the second limiting portion can be formed at the opening position of the shell by folding the shell, and the molding is simple.

[0025] In some embodiments, the end cap further includes a second protrusion protruding from an outer surface of the cap body in a direction away from the electrode assembly, and an outer surface of the second protrusion is flush with an outer surface of the second limiting portion.

[0026] In the above technical solution, the outer surface of the second protrusion is flush with the outer surface of the second limiting portion, which facilitates the connection between the second protrusion and the confluence component and ensures that the two have a larger contact area after connection to facilitate flow.

[0027] In some embodiments, the first protrusion is welded to the first tab.

[0028] In the above technical solution, the first protrusion is welded to the first tab, so that the first protrusion always maintains good contact with the first tab. The connection between the first protrusion and the first tab is achieved by welding, which is simple to implement.

[0029] In a second aspect, an embodiment of the present application provides a battery, comprising a battery cell provided by any one embodiment of the first aspect; and a box for accommodating the battery cell.

[0030] In a third aspect, an embodiment of the present application provides an electrical device, comprising a battery provided in any one embodiment of the second aspect.

[0031] In a fourth aspect, an embodiment of the present application provides a method for manufacturing a battery cell, the method comprising: providing an electrode assembly, the electrode assembly having a first pole ear; providing a shell, the shell having an opening and a first limiting portion; providing an end cover; accommodating the electrode assembly in the shell; covering the end cover on the opening; wherein the end cover comprises a cover body, the cover body being used to cover the opening, and in the thickness direction of the end cover, the cover body is located on the side of the first limiting portion away from the electrode assembly, the first limiting portion being used to limit the movement of the cover body relative to the shell in a direction facing the electrode assembly; the end cover also comprises a first protrusion protruding from the inner surface of the cover body in a direction facing the electrode assembly, the first protrusion being configured to exceed the first limiting portion in a direction away from the cover body so that the first protrusion is pressed against the first pole ear.

[0032] In the fifth aspect, an embodiment of the present application also provides a manufacturing device for a battery cell, comprising: a first providing device for providing an electrode assembly, the electrode assembly having a first pole ear; a second providing device for providing a shell, the shell having an opening and a first limiting portion; a third providing device for providing an end cover; an assembling device for accommodating the electrode assembly in the shell and for covering the end cover on the opening; wherein the end cover includes a cover body, the cover body is used to cover the opening, and in the thickness direction of the end cover, the cover body is located on the side of the first limiting portion away from the electrode assembly, and the first limiting portion is used to limit the movement of the cover body relative to the shell in a direction facing the electrode assembly; the end cover also includes a first convex portion protruding from the inner surface of the cover body in a direction facing the electrode assembly, and the first convex portion is configured to exceed the first limiting portion in a direction away from the cover body so that the first convex portion is pressed against the first pole ear. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0035] Figure 2 A schematic diagram of the structure of a battery provided in some embodiments of the present application;

[0036] Figure 3 An exploded view of a battery cell provided in some embodiments of the present application;

[0037] Figure 4 for Figure 3 A cross-sectional view of a battery cell is shown;

[0038] Figure 5 for Figure 4 A partial enlarged view of the battery cell A shown;

[0039] Figure 6 for Figure 4 A partial view of a battery cell is shown;

[0040] Figure 7 A flowchart of a method for manufacturing a battery cell provided in some embodiments of the present application;

[0041] Figure 8 A schematic block diagram of a battery cell manufacturing device provided in some embodiments of the present application.

[0042] Icons: 10 - housing; 11 - first part; 12 - second part; 13 - accommodating chamber; 20 - battery cell; 21 - electrode assembly; 211 - main body; 212 - first tab; 213 - second tab; 214 - center hole; 22 - housing; 221 - opening; 222 - first limiting portion; 223 - housing body; 2231 - roller groove; 224 - covering body; 225 - second limiting portion; 23 - end cap; 231 - cover body; 232 - first convex portion; 2321 - abutting plane; 233 - second convex portion; 234 - injection hole; 235 - diversion channel; 236 - recessed portion; 237-liquid outlet surface; 24-sealed space; 25-first insulating member; 251-insulating portion; 2511-first insulating section; 2512-second insulating section; 2513-third insulating section; 252-pressing portion; 26-second insulating member; 261-surrounding body; 262-covering portion; 27-sealing member; 100-battery; 200-controller; 300-motor; 1000-vehicle; 2000-manufacturing equipment; 2100-first providing device; 2200-second providing device; 2300-third providing device; 2400-assembling device; Z-thickness direction. DETAILED DESCRIPTION

[0043] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0044] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0045] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0046] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0047] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0048] The term "plurality" used in this application refers to two or more (including two).

[0049] In this application, battery cells 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 do not limit this. Battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the embodiments of this application do not limit this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0050] The battery referred to in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in this application may include a battery module or a battery pack. A battery generally includes a casing that encloses one or more battery cells. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0051] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode sheet, a negative electrode sheet, and a separator. A battery cell primarily operates by the movement of metal ions between the positive and negative electrode sheets. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive electrode collector. The uncoated positive electrode collector protrudes from the coated positive electrode collector, and the uncoated positive electrode collector serves as the positive electrode tab. For lithium-ion batteries, for example, the positive electrode current collector can be made of aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative electrode collector. The uncoated negative electrode collector protrudes from the coated negative electrode collector, and the uncoated negative electrode collector serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon or silicon, among others. To ensure that high currents can pass without fusing, multiple positive electrode tabs are stacked together, and multiple negative electrode tabs are stacked together. The separator can be made of materials such as PP (polypropylene) or PE (polyethylene). Furthermore, the electrode assembly can be a wound or laminated structure, but the embodiments of the present application are not limited thereto.

[0052] For typical battery cells, the end cap needs to be electrically connected to the tab to serve as the output electrode (positive or negative) of the battery cell. However, after actual assembly, it is easy for the end cap and the tab to not make good contact, resulting in the battery cell not functioning properly. The inventors discovered that in battery cells, the housing generally has a limiter that restricts the end cap, limiting its movement in the direction facing the electrode assembly. In this case, the tab may also be restricted by the limiter, resulting in improper or poor contact between the end cap and the tab, thus causing the battery cell to not function properly.

[0053] In view of this, an embodiment of the present application provides a technical solution, wherein the end cover includes a cover body and a first protrusion, the cover body being used to cover the opening of the shell, the cover body being located on the side of the first limiting portion away from the electrode assembly, and the first protrusion extending beyond the first limiting portion in a direction away from the cover body, so that the first protrusion is pressed against the first pole ear, ensuring good contact between the first protrusion and the first pole ear, increasing the flow area between the first pole ear and the end cover, reducing the risk of the first pole ear being unable to contact the end cover due to being restricted by the first limiting portion of the shell, and ensuring battery performance.

[0054] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0055] Electrical equipment can be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and electric tools, etc. Vehicles can be fuel vehicles, gas vehicles, or new energy vehicles. New energy vehicles can be pure electric vehicles, hybrid vehicles, or extended-range vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical equipment.

[0056] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0057] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of the present application. A battery 100 is disposed inside the vehicle 1000. The battery 100 can be disposed at the bottom, head, or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000.

[0058] The vehicle 1000 may further include a controller 200 and a motor 300 . The controller 200 is used to control the battery 100 to supply power to the motor 300 , for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0059] In some embodiments of the present application, the battery 100 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0060] In some embodiments, please refer to Figure 2 , Figure 2 This is a structural diagram of a battery 100 provided in some embodiments of the present application. The battery 100 includes a box body 10 and a battery cell 20 . The box body 10 is used to accommodate the battery cell 20 .

[0061] The box body 10 may include a first portion 11 and a second portion 12, which cover each other to define a receiving cavity 13 for receiving the battery cell 20. The first portion 11 and the second portion 12 may be in various shapes, such as a rectangular parallelepiped, a cylinder, etc. The first portion 11 may be a hollow structure with one side open, and the second portion 12 may also be a hollow structure with one side open. The open side of the second portion 12 covers the open side of the first portion 11, thereby forming the box body 10 with the receiving cavity 13. Figure 2 As shown, the first part 11 may be a hollow structure with one side open, and the second part 12 may be a plate-like structure. The second part 12 covers the open side of the first part 11, thereby forming a box body 10 with a receiving cavity 13. Figure 2 In the figure, the first part 11 and the second part 12 are both rectangular parallelepiped structures.

[0062] The first portion 11 and the second portion 12 can be sealed by a sealing element, which can be a sealing ring, sealant, etc.

[0063] In the battery 100, there can be one or more battery cells 20. If there are multiple battery cells 20, the multiple battery cells 20 can be connected in series, parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. Multiple battery cells 20 can be connected in series, parallel, or in a hybrid connection to form a battery module, which is then connected in series, parallel, or in a hybrid connection to form a whole and housed within the housing 10. Alternatively, all battery cells 20 can be directly connected in series, parallel, or in a hybrid connection, and then the whole battery module can be housed within the housing 10.

[0064] In some embodiments, the battery 100 may further include a busbar component, and the multiple battery cells 20 may be electrically connected via the busbar component to achieve series connection, parallel connection, or mixed connection of the multiple battery cells 20 .

[0065] The busbar component may be a metal conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0066] Please refer to Figure 3 and Figure 4 , Figure 3 An exploded view of a battery cell 20 provided in some embodiments of the present application, Figure 4 for Figure 3 The battery cell 20 shown in FIG. 1 is a cross-sectional view of a battery cell 20, which includes an electrode assembly 21, a housing 22, and an end cap 23. The electrode assembly 21 has a first electrode tab 212. The housing 22 has an opening 221 and a first stopper 222, and is used to accommodate the electrode assembly 21. The end cap 23 includes a cover body 231, which is used to cover the opening 221. In the thickness direction Z of the end cap 23, the cover body 231 is located on the side of the first stopper 222 facing away from the electrode assembly 21. The first stopper 222 is used to limit the movement of the cover body 231 relative to the housing 22 in a direction facing the electrode assembly 21. The end cap 23 also includes a first protrusion 232 protruding from the inner surface of the cover body 231 in a direction facing the electrode assembly 21. The first protrusion 232 is configured to extend beyond the first stopper 222 in a direction away from the cover body 231, so that the first protrusion 232 presses against the first electrode tab 212.

[0067] Since the first protrusion 232 of the end cover 23 extends beyond the first limiting portion 222 in a direction away from the cover body 231, the protrusion presses against the first pole tab 212, ensuring good contact between the first protrusion 232 and the first pole tab 212, increasing the flow area between the first pole tab 212 and the end cover 23, and reducing the risk of the first pole tab 212 being restricted by the first limiting portion 222 of the shell 22 and unable to contact the end cover 23, thereby ensuring the performance of the battery 100.

[0068] The first protrusion 232 presses against the first tab 212 to electrically connect the end cap 23 to the first tab 212. In some embodiments, the first protrusion 232 can be fixedly connected to the first tab 212. For example, the first protrusion 232 can be welded to the first tab 212 so that the first protrusion 232 always maintains good contact with the first tab 212. Welding the first protrusion 232 to the first tab 212 is simple to implement.

[0069] In some embodiments, in the thickness direction Z of the end cap 23, the first protrusion 232 has an abutting plane 2321 that abuts against the first electrode tab 212, thereby increasing the contact area between the first electrode tab 212 and the first protrusion 232, thereby increasing the flow area between the first electrode tab 212 and the end cap 23. The abutting plane 2321 is closer to the electrode assembly 21 as a whole than the first limiting portion 222, so that the first protrusion 232 extends beyond the first limiting portion 222 in a direction away from the cap body 231.

[0070] During the actual assembly process, after the cover body 231 of the end cover 23 is covered on the opening 221 of the shell 22 and the abutting plane 2321 is pressed against the first pole ear 212, the first protrusion 232 and the first pole ear 212 can be welded together on the outside of the end cover 23, for example, by laser welding.

[0071] In some embodiments, the electrode assembly 21 includes a main body 211, a first electrode tab 212, and a second electrode tab 213. The first electrode tab 212 and the second electrode tab 213 have opposite polarities. The first electrode tab 212 and the second electrode tab 213 both protrude from the main body 211. The first electrode tab 212 is used to electrically connect to the end cap 23, and the second electrode tab 213 is used to electrically connect to the housing 22.

[0072] The first tab 212 and the second tab 213 can be provided at opposite ends of the main body 211, or at the same end of the main body 211. Figure 4 In the embodiment, the first electrode tab 212 and the second electrode tab 213 are respectively disposed at two opposite ends of the main body 211 .

[0073] The main body 211 may include a positive electrode sheet, a negative electrode sheet, and a separator. The main body 211 may be a wound structure formed by winding the positive electrode sheet, separator, and negative electrode sheet. The main body 211 may also be a stacked structure formed by stacking the positive electrode sheet, separator, and negative electrode sheet.

[0074] The positive electrode sheet includes a positive current collector and a positive active material layer coated on opposite sides of the positive current collector. The negative electrode sheet includes a negative current collector and a negative active material layer coated on opposite sides of the negative current collector. The main body 211 can be the portion of the electrode assembly 21 corresponding to the area of the electrode sheet coated with the active material layer, and the tab can be the portion of the electrode assembly 21 corresponding to the area of the electrode sheet not coated with the active material layer.

[0075] One of the first electrode tab 212 and the second electrode tab 213 is a positive electrode tab, and the other is a negative electrode tab. That is, if the first electrode tab 212 is a positive electrode tab, the second electrode tab 213 is a negative electrode tab; if the first electrode tab 212 is a negative electrode tab, the second electrode tab 213 is a positive electrode tab. The positive electrode tab can be an area on the positive electrode sheet that is not coated with the positive electrode active material layer, and the negative electrode tab can be an area on the negative electrode sheet that is not coated with the negative electrode active material layer.

[0076] In the embodiment of the present application, the shell 22 is used to accommodate the electrode assembly 21. After the cover body 231 of the end cover 23 covers the opening 221 of the shell 22, the end cover 23 and the shell 22 together form a sealed space 24 for accommodating the electrode assembly 21 and the electrolyte, which can be an electrolyte.

[0077] The shell 22 can be in various shapes, such as a cylinder, a cuboid, etc. The shape of the shell 22 can be determined according to the specific shape of the electrode assembly 21. For example, if the electrode assembly 21 is a cylindrical structure, the shell 22 can be a cylindrical structure; if the electrode assembly 21 is a cuboid structure, the shell 22 can be a cuboid structure. Figure 4 In the embodiment, the shell 22 is a hollow cylindrical structure.

[0078] The housing 22 may be made of metal, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0079] In some embodiments, please refer to Figure 4 The shell 22 may include a shell body 223 and a cover body 224. The shell body 223 is a hollow structure with both ends open. The cover body 224 is connected to one end of the shell body 223 so that the other end of the shell body 223 forms an opening 221, and the cover body 231 of the end cover 23 covers the opening 221.

[0080] Illustratively, the first tab 212 of the electrode assembly 21 is electrically connected to the end cap 23, and the second tab 213 of the electrode assembly 21 is electrically connected to the cover 224 of the housing 22. The first tab 212 and the end cap 23, as well as the second tab 213 and the cover 224, can be connected by welding.

[0081] The cover 224 and the shell body 223 can be an integrally formed structure or a separate structure. In the case where the cover 224 and the shell body 223 are separate structures, the structure of the cover 224 can be the same as or different from the structure of the end cap 23, the connection method between the cover 224 and the shell body 223 can be the same as or different from the connection method between the end cap 23 and the shell body 223, and the connection method between the cover 224 and the second electrode tab 213 can be the same as or different from the connection method between the end cap 23 and the first electrode tab 212.

[0082] For example, in Figure 4 In the embodiment, the shell body 223 is a cylindrical structure, the cover body 224 is a plate-shaped structure, and the cover body 224 and the shell body 223 are separate structures.

[0083] In some embodiments, in the thickness direction Z of the end cover 23 , the first limiting portion 222 of the shell 22 covers at least a portion of the first electrode tab 212 , and the first limiting portion 222 can limit the electrode assembly 21 from detaching from the shell 22 from the opening 221 of the shell 22 .

[0084] Specifically, the first limiting portion 222 is formed on the shell body 223 of the housing 22. For example, the first limiting portion 222 can be an annular structure protruding from the inner circumference of the shell body 223.

[0085] Optionally, a roller groove 2231 is formed on the outer circumference of the shell body 223 at a position corresponding to the first limiting portion 222. In the actual molding process, the roller groove 2231 can be rolled out on the outer circumference of the shell body 223 by rolling, and the inwardly convex first limiting portion 222 is formed on the inner circumference of the shell body 223.

[0086] It should be noted that the cover body 231 of the end cap 23 can be insulated or electrically connected to the shell body 22. If the cover body 224 and the shell body 223 are an integral structure, or the cover body 224 and the shell body 223 are separate structures and the cover body 224 and the shell body 223 are electrically connected, the cover body 231 and the shell body 223 of the shell 22 can be insulated to reduce the risk of short circuit. If the cover body 224 and the shell body 223 are separate structures and the cover body 224 and the shell body 223 are insulated, the cover body 231 and the shell body 223 of the shell 22 can be electrically connected to reduce the risk of short circuit.

[0087] In some embodiments, please refer to Figure 5 , Figure 5 for Figure 4 The battery cell 20 is shown in a partially enlarged view. The battery cell 20 further includes a first insulating member 25, which is used to isolate the cover body 231 from the housing 22 to achieve an insulated connection between the cover body 231 and the housing 22, thereby maintaining insulation between the cover body 231 and the housing 22. It can be understood that the first insulating member 25 is used to achieve an insulated connection between the cover body 231 and the housing 22, that is, the first insulating member 25 is used to achieve an insulated connection between the cover body 231 and the housing 22.

[0088] Because the cover body 231 is insulated from the housing 22 by the first insulating member 25, even if the housing 22 and the end cap 23 carry different polarities, it is unlikely that the cover body 231 will contact the housing 22 and cause a short circuit. However, if the first tab 212 tilts and contacts the first stopper 222 of the housing 22, a short circuit may still occur.

[0089] In the embodiment of the present application, since the first protrusion 232 of the end cover 23 extends beyond the first limiting portion 222 in a direction away from the cover body 231, and the first protrusion 232 is pressed against the first pole ear 212, the first protrusion 232 can limit the first pole ear 212, thereby reducing the risk of positive and negative pole short circuits caused by the pole ear tilting up and contacting the first limiting portion 222.

[0090] The first insulating member 25 may be made of insulating materials such as plastic, rubber, etc.

[0091] The end cap 23 can serve as one output pole of the battery cell 20, and the shell body 223 or cover 224 of the housing 22 can serve as the other output pole of the battery cell 20. The end cap 23 can serve as the positive output pole, with the shell body 223 or cover 224 serving as the negative output pole; alternatively, the end cap 23 can serve as the negative output pole, with the shell body 223 or cover 224 serving as the full output pole. The positive and negative output poles are the parts of the battery cell 20 that connect to other components and output the electrical energy of the battery cell 20. For example, in which two battery cells 20 are electrically connected via a busbar to achieve series connection, the positive output pole of one battery cell 20 and the negative output pole of the other battery cell 20 are both welded to the same busbar.

[0092] In some embodiments, the cover body 231 is sealed to the housing 22 via the first insulating member 25 , that is, the first insulating member 25 plays both an insulating and sealing role between the cover body 231 and the housing 22 .

[0093] In some embodiments, the first insulating member 25 includes an insulating portion 251 and a pressing portion 252. The insulating portion 251 is used to isolate the cover body 231 from the housing 22 to achieve an insulated connection between the cover body 231 and the housing 22. The pressing portion 252 is connected to the insulating portion 251 and is used to press against the first tab 212. The pressing portion 252 restricts the first tab 212, reducing the risk of the first tab 212 tilting and contacting the first limiting portion 222, which could cause a short circuit between the positive and negative electrodes. In other words, the first insulating member 25 can simultaneously achieve insulation between the cover body 231 and the housing 22 while also restricting the first tab 212.

[0094] Illustratively, the cover body 231 is sealed and connected to the housing 22 via the insulating portion 251 of the first insulating member 25 .

[0095] In some embodiments, the insulating portion 251 may include a first insulating segment 2511, a second insulating segment 2512, and a third insulating segment 2513. The pressing portion 252, the first insulating segment 2511, the second insulating segment 2512, and the third insulating segment 2513 are sequentially connected. The first insulating segment 2511 and the third insulating segment 2513 are respectively located on either side of the cover body 231 in the thickness direction Z of the end cap 23. The cover body 231 abuts against the first limiting portion 222 via the first insulating segment 2511, so that the first limiting portion 222 restricts the cover body 231 from moving in a direction facing the electrode assembly 21. The second insulating segment 2512 is located between the inner circumference of the housing 22 and the outer circumference of the cover body 231. This structure of the insulating portion 251 provides both excellent insulation and sealing between the cover body 231 and the housing 22.

[0096] Illustratively, the first insulating segment 2511 , the second insulating segment 2512 , and the third insulating segment 2513 are all annular structures extending along the circumference of the cover body 231 .

[0097] In some embodiments, in the thickness direction Z of the end cap 23, the pressing portion 252 extends from the insulating portion 251 in a direction facing the tab, so that the pressing portion 252 presses against the first tab 212. This structure allows the pressing portion 252 to better press the first tab 212, making the first tab 212 less likely to warp.

[0098] Illustratively, in the thickness direction Z of the end cover 23 , the pressing portion 252 extends from the first insulating segment 2511 of the insulating portion 251 in a direction facing the first electrode tab 212 .

[0099] In some embodiments, the pressing portion 252 is located on the periphery of the first protrusion 232 , and the first limiting portion 222 is located on the periphery of the pressing portion 252 . The pressing portion 252 is used to isolate the first protrusion 232 and the first limiting portion 222 .

[0100] That is, the pressing portion 252 is located between the first protrusion 232 and the first limiting portion 222, so that the pressing portion 252 serves to isolate the first protrusion 232 and the first limiting portion 222, thereby reducing the risk of short circuit caused by contact between the first protrusion 232 and the first limiting portion 222.

[0101] In some embodiments, the pressing portion 252 is an annular structure, which can press the first electrode tab 212 all around, thereby providing a better restriction on the first electrode tab 212 .

[0102] For example, the pressing portion 252 is an annular structure disposed around the outer periphery of the first protrusion 232. The pressing portion 252 of this structure can achieve complete isolation of the first protrusion 232 and the first limiting portion 222.

[0103] In the embodiment of the present application, the pressing portion 252 presses against the first electrode tab 212 . The pressing portion 252 may press against the first electrode tab 212 directly or indirectly.

[0104] In some embodiments, the battery cell 20 further includes a second insulating member 26, which is used to isolate the first electrode tab 212 from the first limiting portion 222. In the thickness direction Z of the end cap 23, the second insulating member 26 covers a portion of the first electrode tab 212, and the pressing portion 252 presses against the first electrode tab 212 through the portion of the first insulating member 25 covering the first electrode tab 212. It is understood that the pressing portion 252 presses against the second insulating member 26 in a direction facing the electrode assembly 21, thereby preventing the second insulating member 26 from tilting.

[0105] The second insulating member 26 can be made of insulating materials such as plastic, rubber, etc.

[0106] Exemplarily, the second insulating member 26 includes a surrounding body 261 and a covering portion 262. The surrounding body 261 is arranged around the outer periphery of the main body 211 of the electrode assembly 21, and the covering portion 262 is connected to one end of the surrounding body 261 in the thickness direction Z of the end cover 23. In the thickness direction Z of the end cover 23, the covering portion 262 covers a portion of the first pole ear 212, and the pressing portion 252 is pressed against the first pole ear 212 through the covering portion 262.

[0107] In some embodiments, please refer to Figure 5 The shell 22 also has a second limiting portion 225. In the thickness direction Z, the cover body 231 is located on the side of the second limiting portion 225 facing the electrode assembly 21. The second limiting portion 225 and the first limiting portion 222 are used to jointly limit the movement of the cover body 231 relative to the shell 22 along the thickness direction Z.

[0108] The first limiting portion 222 limits the cover body 231 from moving relative to the shell 22 in a direction facing the electrode assembly 21 , and the second limiting portion 225 limits the cover body 231 from moving relative to the shell 22 in a direction away from the electrode assembly 21 .

[0109] Optionally, the second stop 225 is a flange structure formed by partially folding the housing 22 inward and forming a flange at the location of the opening 221. In other words, by folding the housing 22, the second stop 225 can be formed at the location of the opening 221 of the housing 22, which simplifies the assembly process. During assembly of the battery cell 20, the electrode assembly 21 can be first housed within the housing 22, and then the end cap 23 can be placed over the opening 221 of the housing 22. Finally, the housing 22 can be folded to form the second stop 225 to limit the position of the end cap 23.

[0110] Specifically, the second limiting portion 225 is a flange structure formed by partially folding the shell body 223 of the shell 22 inward and at the position of the opening 221 .

[0111] Illustratively, the second limiting portion 225 is a ring-shaped structure.

[0112] In some embodiments, as Figure 5 As shown, when the cover body 231 and the shell 22 are insulated and connected through the first insulating member 25, the second limiting portion 225 can be pressed against the cover body 231 through the third insulating segment 2513, so that the third insulating segment 2513 is located between the inner surface of the second limiting portion 225 and the outer surface of the cover body 231 in the thickness direction Z of the end cover 23.

[0113] In other embodiments, if the cover body 231 is electrically connected to the shell 22, the first limiting portion 222 and the second limiting portion 225 can directly abut against the inner surface and outer surface of the cover body 231 respectively. In this case, the shell body 223 of the shell 22 can be insulated from the cover body 224.

[0114] In some embodiments, please refer to Figure 6 , Figure 6 for Figure 4 In the partial view of the battery cell 20 shown, the end cover 23 also includes a second protrusion 233 protruding from the outer surface of the cover body 231 in a direction away from the electrode assembly 21. The outer surface of the second protrusion 233 is flush with the outer surface of the second limiting portion 225, which facilitates the connection between the second protrusion 233 and the confluence component, ensuring that the two have a larger contact area after connection to facilitate current flow.

[0115] Exemplarily, the second limiting portion 225 is distributed around the outer circumference of the second protrusion 233 .

[0116] In some embodiments, the second limiting portion 225 and the second protrusion 233 respectively serve as the two output poles of the battery cell 20. The second protrusion 233 can serve as the positive output pole, and the second limiting portion 225 as the negative output pole. Alternatively, the second protrusion 233 can serve as the negative output pole, and the second limiting portion 225 as the positive output pole. For example, in the case of two battery cells 20 electrically connected via a busbar to achieve series connection of the two battery cells 20, the second limiting portion 225 of one battery cell 20 and the second protrusion 233 of the other battery cell 20 are both welded to the same busbar.

[0117] Since the outer surface of the second protrusion 233 is flush with the outer surface of the second limiting portion 225 , it is ensured that after the outer surface of the second protrusion 233 is connected to one confluence component, the outer surface of the second limiting portion 225 can be connected to another confluence component.

[0118] In some embodiments, please refer to Figure 6 The end cap 23 is provided with an injection hole 234 through which electrolyte can be injected into the battery cell 20. The outer peripheral surface of the first protrusion 232 is located outside the injection hole 234. The first protrusion 232 is provided with a guide channel 235 for allowing electrolyte to flow outside the outer peripheral surface of the first protrusion 232.

[0119] When the electrolyte is injected into the battery cell 20 through the injection hole 234, the electrolyte can flow laterally from the guide channel 235 and eventually flow to the outside of the outer peripheral surface of the first protrusion 232, thereby improving the injection efficiency, achieving efficient injection, and making it easier for the electrolyte to infiltrate the electrode plates in the electrode assembly 21.

[0120] Illustratively, the liquid injection hole 234 is coaxially disposed with the outer circumferential surface of the first protrusion 232 .

[0121] There can be one or more guide channels 235 on the first convex portion 232 . If there are more than one guide channel 235 , the guide channels 235 can be circumferentially spaced and distributed on the first convex portion 232 with the injection hole 234 as the center.

[0122] In some embodiments, the electrode assembly 21 has a center hole 214. In the thickness direction Z of the end cover 23, the guide channel 235 is coaxially arranged with the center hole 214, so that the electrolyte entering the injection hole 234 can directly enter the center hole 214 to infiltrate the electrode plates in the electrode assembly 21.

[0123] In some embodiments, the end cap 23 is provided with a recess 236, which is recessed from the end of the first protrusion 232 that abuts the first tab 212, away from the electrode assembly 21. The ends of the flow channel 235 extend through the inner circumference of the recess 236 and the outer circumference of the first protrusion 232, respectively. The end cap 23 has a liquid outlet surface 237 located within the recess 236. The bottom end of the injection hole 234 extends through the liquid outlet surface 237. In the thickness direction Z of the end cap 23, the liquid outlet surface 237 is further away from the electrode assembly 21 than the abutment plane 2321 of the first protrusion 232. This creates a distance between the liquid outlet surface 237 and the first tab 212 in the thickness direction Z of the end cap 23. This structure allows the electrolyte to enter the battery cell 20 through the injection hole 234, first into the recess 236, and then into the flow channel 235, facilitating lateral flow of the electrolyte beyond the outer circumference of the first protrusion 232.

[0124] Exemplarily, the guide channel 235 is a groove provided on the abutting plane 2321 and penetrating the inner circumferential surface of the recessed portion 236 and the outer circumferential surface of the first protruding portion 232 .

[0125] In some embodiments, the battery cell 20 further includes a sealing member 27 for sealing the liquid injection hole 234. After liquid is injected into the battery cell 20 through the liquid injection hole 234, the sealing member 27 can be used to seal the liquid injection hole 234.

[0126] The present invention provides a method for manufacturing a battery cell 20. Figure 7 , Figure 7 This is a flow chart of a method for manufacturing a battery cell 20 provided in some embodiments of the present application. The manufacturing method includes:

[0127] S100: Providing an electrode assembly 21, wherein the electrode assembly 21 has a first electrode tab 212;

[0128] S200: Providing a housing 22, wherein the housing 22 has an opening 221 and a first limiting portion 222;

[0129] S300: providing an end cap 23;

[0130] S400: accommodating the electrode assembly 21 in the housing 22;

[0131] S500 : Cover the end cover 23 on the opening 221 of the housing 22 .

[0132] Among them, the end cover 23 includes a cover body 231, which is used to cover the opening 221. In the thickness direction Z of the end cover 23, the cover body 231 is located on the side of the first limiting portion 222 away from the electrode assembly 21, and the first limiting portion 222 is used to limit the movement of the cover body 231 relative to the shell 22 in the direction facing the electrode assembly 21; the end cover 23 also includes a first protrusion 232 protruding from the inner surface of the cover body 231 in the direction facing the electrode assembly 21, and the first protrusion 232 is configured to exceed the first limiting portion 222 in the direction away from the cover body 231, so that the first protrusion 232 is pressed against the first electrode ear 212.

[0133] In the above method, the order of step S100, step S200 and step S300 is not limited. For example, step S300 may be performed first, then step S200, and then step S100.

[0134] It should be noted that the relevant structures of the battery cells 20 manufactured by the manufacturing methods provided in the above embodiments can refer to the battery cells 20 provided in the above embodiments, and will not be described in detail here.

[0135] In addition, the present invention also provides a manufacturing device 2000 for a battery cell 20, please refer to Figure 8 , Figure 8 This is a schematic block diagram of a manufacturing apparatus 2000 for a battery cell 20 provided in some embodiments of the present application. The manufacturing apparatus 2000 includes a first providing device 2100 , a second providing device 2200 , a third providing device 2300 , and an assembling device 2400 .

[0136] The first providing device 2100 is used to provide the electrode assembly 21, which has a first electrode tab 212. The second providing device 2200 is used to provide the housing 22, which has an opening 221 and a first stopper 222. The third providing device 2300 is used to provide the end cap 23. The assembly device 2400 is used to accommodate the electrode assembly 21 in the housing 22 and to cover the end cap 23 with the opening 221.

[0137] Among them, the end cover 23 includes a cover body 231, which is used to cover the opening 221. In the thickness direction Z of the end cover 23, the cover body 231 is located on the side of the first limiting portion 222 away from the electrode assembly 21, and the first limiting portion 222 is used to limit the movement of the cover body 231 relative to the shell 22 in the direction facing the electrode assembly 21; the end cover 23 also includes a first protrusion 232 protruding from the inner surface of the cover body 231 in the direction facing the electrode assembly 21, and the first protrusion 232 is configured to exceed the first limiting portion 222 in the direction away from the cover body 231, so that the first protrusion 232 is pressed against the first electrode ear 212.

[0138] It should be noted that the relevant structures of the battery cells 20 manufactured by the manufacturing equipment 2000 provided by the above embodiment can refer to the battery cells 20 provided by the above embodiments, and will not be repeated here.

[0139] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0140] The above embodiments are intended only to illustrate the technical solutions of this application and are not intended to limit this application. Those skilled in the art will appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application are intended to be within the scope of protection of this application.

Claims

1. A battery cell, characterized in that: include: An electrode assembly having a first tab; a shell having an opening and a first limiting portion, wherein the shell is used to accommodate the electrode assembly; an end cap, comprising a cap body, the cap body being configured to cover the opening, the cap body being located on a side of the first limiting portion facing away from the electrode assembly in a thickness direction of the end cap, the first limiting portion being configured to limit movement of the cap body relative to the housing in a direction facing the electrode assembly; The end cap further includes a first protrusion protruding from the inner surface of the cap body in a direction facing the electrode assembly, and the first protrusion is configured to exceed the first limiting portion in a direction away from the cap body so that the first protrusion presses against the first electrode tab.

2. The battery cell according to claim 1, wherein: In the thickness direction, the first protrusion has a contact plane against the first electrode tab, and the contact plane is closer to the electrode assembly than the first limiting portion as a whole.

3. The battery cell according to claim 1, wherein: The battery cell further comprises: The first insulating member is used to isolate the cover body from the shell to achieve an insulating connection between the cover body and the shell.

4. The battery cell according to claim 3, characterized in that The first insulating member comprises: an insulating portion, used to isolate the cover body from the housing; The pressing portion is connected to the insulating portion and is used to press against the first electrode tab.

5. The battery cell according to claim 4, characterized in that In the thickness direction, the pressing portion extends from the insulating portion in a direction facing the electrode tab to press against the first electrode tab.

6. The battery cell according to claim 4, characterized in that The pressing portion is located at the outer periphery of the first convex portion, and the first limiting portion is located at the outer periphery of the pressing portion. The pressing portion is used to isolate the first convex portion and the first limiting portion.

7. The battery cell according to claim 4, characterized in that The pressing portion is an annular structure.

8. The battery cell according to claim 3, characterized in that The cover body is sealed and connected to the housing through the first insulating member.

9. The battery cell according to any one of claims 1 to 8, characterized in that: The housing further comprises a second limiting portion; In the thickness direction, the cover body is located on a side of the second limiting portion facing the electrode assembly, and the second limiting portion and the first limiting portion are used to jointly limit the cover body from moving relative to the shell along the thickness direction.

10. The battery cell according to claim 9, characterized in that: The second limiting portion is a flange structure formed by partially folding the shell inward and forming the flange structure at the opening position.

11. The battery cell according to claim 9, characterized in that The end cap further includes a second protrusion protruding from an outer surface of the cap body in a direction away from the electrode assembly, and an outer surface of the second protrusion is flush with an outer surface of the second limiting portion.

12. The battery cell according to any one of claims 1 to 8, characterized in that: The first protrusion is welded to the first tab.

13. A battery, characterized in that: include: The battery cell according to any one of claims 1 to 12; as well as The box is used to accommodate the battery cells.

14. An electrical device, characterized in that: Including the battery according to claim 13.

15. A method for manufacturing a battery cell, characterized in that: The manufacturing method comprises: Providing an electrode assembly, the electrode assembly having a first tab; Providing a housing having an opening and a first limiting portion; Provide end caps; accommodating the electrode assembly in the housing; Covering the end cover on the opening; The end cover includes a cover body, the cover body is used to cover the opening, and in the thickness direction of the end cover, the cover body is located on the side of the first limit portion away from the electrode assembly, and the first limit portion is used to limit the movement of the cover body relative to the housing in a direction facing the electrode assembly; The end cap further includes a first protrusion protruding from the inner surface of the cap body in a direction facing the electrode assembly, and the first protrusion is configured to exceed the first limiting portion in a direction away from the cap body so that the first protrusion presses against the first electrode tab.

16. A battery cell manufacturing device, characterized in that: include: A first providing device is used to provide an electrode assembly, wherein the electrode assembly has a first electrode tab; A second providing device is used to provide a housing having an opening and a first limiting portion; a third providing device for providing an end cap; an assembling device for accommodating the electrode assembly in the housing and for closing the end cap on the opening; The end cover includes a cover body, the cover body is used to cover the opening, and in the thickness direction of the end cover, the cover body is located on the side of the first limit portion away from the electrode assembly, and the first limit portion is used to limit the movement of the cover body relative to the housing in a direction facing the electrode assembly; The end cap further includes a first protrusion protruding from the inner surface of the cap body in a direction facing the electrode assembly, and the first protrusion is configured to exceed the first limiting portion in a direction away from the cap body so that the first protrusion presses against the first electrode tab.

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