Battery cell, battery, and electric device

Abstract

The present application relates to the field of batteries, and provides a battery cell (20), a battery (100), and an electric device. The battery cell (20) comprises: a casing (21); an electrode assembly (22) provided in the casing (21) and comprising a first tab (221) and a second tab (222); and a first electrode terminal (23) comprising a first body (231) and a first pole (232) protruding from one side of the first body (231), wherein the first pole (232) passes through the casing (21), the first body (231) is arranged in the casing (21) and is electrically connected to the first tab (221), at least one of the first body (231) and the first pole (232) is provided with a fusing portion (233), and the current passing area of the fusing portion (233) is smaller than the current passing area of a region adjacent to the fusing portion (233). The battery cell provided in embodiments of the present application is provided with a fusing portion, thereby improving the use safety.

Description

Battery cells, batteries and electrical equipment

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 7, 2023, with application number 202322433324.1, and invention name “Battery Cell, Battery and Electrical Equipment”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Art

[0003] Batteries are widely used in electrical 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.

[0004] During battery use, it is easy for internal short circuits to cause the battery current to increase instantly, thus damaging electrical equipment. Therefore, how to improve battery safety is also an urgent problem to be solved.

[0005] Summary of the Invention

[0006] In view of this, embodiments of the present application provide a battery cell, a battery, and an electrical device that can improve safety in use.

[0007] An embodiment of the first aspect of the present application provides a battery cell, comprising:

[0008] shell;

[0009] an electrode assembly disposed in the housing and comprising a first electrode tab and a second electrode tab;

[0010] A first electrode terminal includes a first body and a first pole protruding from one side of the first body, the first pole passing through the housing, and the first body being disposed within the housing and electrically connected to the first tab;

[0011] At least one of the first body and the first pole has a fuse portion, and a flow area of ​​the fuse portion is smaller than a flow area of ​​an adjacent region thereof.

[0012] The battery cell provided in the embodiment of the present application includes a shell, an electrode assembly and an electrode terminal. The first electrode terminal includes a first body and a first pole protruding from one side of the first body. At least one of the first body and the first pole has a fuse part. The flow area of ​​the fuse part is smaller than the flow area of ​​its adjacent area. Therefore, the fuse part on the first electrode terminal can melt when the current exceeds the threshold, and the battery cell no longer continues to supply power to protect the battery cell and the circuit in which it is located, and reduce the probability of overcurrent damage to the battery cell and electrical equipment; the melting of the fuse part can also reduce the probability of thermal runaway, thereby improving the safety of the battery cell.

[0013] In some embodiments, the first body and / or the first pole has a groove, and the position of the groove forms the fuse part.

[0014] By providing a groove on the first body and / or the first pole, the flow area of ​​the fuse can be reduced, so that the flow area of ​​the fuse is smaller than the flow area of ​​its adjacent area; at the same time, the manufacturing method of the groove is relatively simple and easy to implement.

[0015] In some embodiments, the fuse portion is provided on the first pole, and the groove is provided on a peripheral wall of the first pole.

[0016] By adopting the above technical solution, the groove is provided on the peripheral wall of the first pole, the flow area of ​​the fuse part is small, and when the current passing through the battery cell exceeds the threshold value, the first pole can be melted at the fuse part; and the groove is provided on the peripheral wall of the first pole, that is, on the outer surface of the first pole, and the manufacturing method is relatively simple.

[0017] In some embodiments, the groove is an annular groove arranged around the peripheral wall of the first pole.

[0018] By providing an annular groove on the circumferential side of the first pole, the overflow area of ​​the fuse portion can be effectively reduced.

[0019] In some embodiments, along the axial direction of the first pole, the first pole includes a first column portion and a second column portion respectively provided at two ends of the fuse portion;

[0020] The first electrode terminal further includes a first insulating structure received in the groove, wherein the first insulating structure is fixedly connected to at least one of the first column portion and the second column portion.

[0021] Since the first insulating structure is still connected to the first column portion and / or the second column portion, the first insulating structure can maintain contact with the sealing ring, and the electrolyte is not likely to leak rapidly and in large quantities.

[0022] In some embodiments, the first insulating structure is a plastic part and is integrally formed with the first pole.

[0023] By adopting the above technical solution, the first insulating structure and the first pole are manufactured in an integrally formed manner, so that the first insulating structure can be fixedly connected to the first column portion and the second column portion by means of a buckle or other structure.

[0024] In some embodiments, the flow area of ​​the fuse portion is greater than or equal to 2 / 3 of the flow area of ​​the second tab.

[0025] By setting the flow area of ​​the fuse part, the fuse part can be caused to melt under preset conditions to meet usage requirements.

[0026] In some embodiments, the flow area of ​​the fuse portion satisfies: π*(W6 / 2) 2 ≥2 / 3*W5*X*T;

[0027] The second electrode tab includes multiple layers of stacked second electrode tab sheets, W5 is the width of the second electrode tab sheet, X is the number of layers of the second electrode tab sheet, T is the thickness of the second electrode tab sheet; and W6 is the diameter of the fuse portion.

[0028] By adopting the above technical solution, the flow area of ​​the second tab can be calculated using the above method, so as to determine the flow area of ​​the fuse part according to the flow area of ​​the second tab, and then determine the size of the fuse part.

[0029] In some embodiments, the first body includes a first connecting portion and a second connecting portion, the first connecting portion being used to electrically connect to the first tab;

[0030] The fuse portion is provided between the first connection portion and the second connection portion.

[0031] By adopting the above technical solution, the fuse part is arranged on the first body, which can also play a role of fusing, thereby improving the safety of the battery and electrical equipment.

[0032] In some embodiments, a groove is provided on a surface of the first body facing away from the first tab, and the position of the groove forms the fuse portion.

[0033] By adopting the above technical solution, the surface of the groove close to the first electrode tab can still be conveniently welded to the first electrode tab.

[0034] In some embodiments, the first tab is welded to the first connecting portion, and a second insulating structure is provided between the second connecting portion and the first tab.

[0035] By adopting the above technical solution, after the fuse part is blown, the first electrode tab will not transmit current to the second connecting part.

[0036] In some embodiments, the second insulating structure is at least one of insulating tape, insulating coating, and insulating colloid.

[0037] By adopting the above technical solution, the manufacturing method of the second insulating structure is simple, flexible and convenient, and the manufacturing efficiency is high.

[0038] In some embodiments, the flow area of ​​the fuse portion is greater than or equal to 2 / 3 of the flow area of ​​the second tab.

[0039] By adopting the above technical solution and setting the flow area of ​​the fuse part, the fuse part can be caused to melt under preset conditions to meet usage requirements.

[0040] In some embodiments, the area of ​​the fuse portion satisfies: L1*L2≥2 / 3*W5*X*T;

[0041] The second electrode tab includes multiple layers of stacked second electrode tab sheets, W5 is the width of the second electrode tab sheet, X is the number of layers of the second electrode tab sheet, and T is the thickness of the second electrode tab sheet; L1 is the length of the fuse portion along the first direction, the first direction is the arrangement direction of the first electrode tab and the second electrode tab, and L2 is the thickness of the fuse portion.

[0042] By adopting the above technical solution, the flow area of ​​the second tab can be calculated using the above method, so as to determine the flow area of ​​the fuse part according to the flow area of ​​the second tab, and then determine the size of the fuse part.

[0043] In some embodiments, the first electrode tab is a positive electrode tab, and the first electrode terminal is a positive electrode terminal.

[0044] By adopting the above technical solution, the fuse part is arranged on the positive electrode terminal, which makes it easier to achieve the fuse condition and makes the battery cell safer.

[0045] In some embodiments, the first body includes a first side surface and a second side surface arranged opposite to each other along a first direction, the distance between the first side surface and the pole is greater than the minimum distance between the second side surface and the pole, and the first direction is the arrangement direction of the first pole tab and the second pole tab.

[0046] By adopting the above technical solution, the first body and the first pole of the first electrode terminal can be offset, and the first body can reserve a certain avoidance space, which is beneficial to the arrangement of components inside the battery cell.

[0047] In some embodiments, the battery cell further includes a second electrode terminal, the second electrode terminal including a second body and a second pole protruding from one side of the second body, the second pole passing through the housing, and the second body disposed within the housing and electrically connected to the second tab;

[0048] The center distance between the first electrode tab and the second electrode tab is smaller than the center distance between the first pole post and the second pole post. The first electrode tab has an offset space in the battery cell, and the length of the offset space is greater than or equal to 8 mm.

[0049] By adopting the above technical solution, the first body is arranged inwardly relative to the first pole, and the first tabs have a larger staggered arrangement space.

[0050] In some embodiments, the first tab has a first weld mark, and a projection of the first weld mark toward the first body completely falls within the first body.

[0051] By adopting the above technical solution, the first electrode tab can be arranged corresponding to the first body to facilitate welding, and the laser welding head can be prevented from directly pressing on the first electrode tab during laser welding to crush or crack the first electrode tab.

[0052] In some embodiments, along the first direction, the distance between the first weld mark and the edge of the first body is greater than or equal to 1 mm; and / or,

[0053] Along the second direction, a distance between the first weld mark and an edge of the first body is greater than or equal to 1 mm.

[0054] By adopting the above technical solution, the first weld mark can be completely placed inside the first body.

[0055] In some embodiments, the first tab is welded to the first body to form a second weld mark, and a ratio of a thickness of the first body to a thickness of the first tab is greater than or equal to 3.

[0056] By adopting the above technical solution, the thickness of the first body can be made greater than the laser welding penetration, and it is not easy to penetrate the first body during welding.

[0057] An embodiment of the second aspect of the present application provides a battery, comprising the battery cell provided in the first aspect.

[0058] An embodiment of the third aspect of the present application provides an electrical device, comprising the battery provided in the second aspect.

[0059] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or conventional technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0061] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0062] FIG2 is a schematic structural diagram of a battery provided in some embodiments of the present application;

[0063] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0064] FIG4 is a top view of the first electrode terminal in the battery cell shown in FIG3 ;

[0065] FIG5 is a cross-sectional view of the first electrode terminal shown in FIG4 along line AA;

[0066] FIG6 is a schematic diagram of the first electrode terminal shown in FIG5 after removing the first insulating structure;

[0067] FIG7 is a bottom view of the side wall of the battery cell shown in FIG3;

[0068] FIG8 is a cross-sectional view of the side wall shown in FIG7 along line BB;

[0069] FIG9 is a partial schematic diagram of the side wall shown in FIG8;

[0070] FIG10 is a schematic structural diagram of a battery cell provided in some other embodiments of the present application;

[0071] FIG11 is a top view of the first electrode terminal shown in FIG10;

[0072] FIG12 is a cross-sectional view of the first electrode terminal shown in FIG11 along line CC;

[0073] FIG13 is a schematic diagram of the first electrode terminal shown in FIG12 after removing the second insulating structure;

[0074] FIG14 is a bottom view of the side wall of the battery cell shown in FIG10;

[0075] FIG15 is a cross-sectional view of the side wall shown in FIG14 along line DD.

[0076] The meanings of the marks in the figure are: 1000, vehicle; 100, battery; 200, controller; 300, motor; 10, box; 11, first part; 12, Part 2; 20. Battery cell; 21. Casing; 211. Side wall; 22. Electrode assembly; 221. First tab; 222. Second tab; 221a. Tab misalignment line; 23. First electrode terminal; 231. First body; 231a. First side; 231b. Second side; 2311. First connecting portion; 2312. Second connecting portion; 232. First pole; 2321. First column portion; 2322. Second column portion; 233. Fuse portion; 2331. Groove; 234. First insulating structure; 235. Second insulating structure; 24. Second electrode terminal; 241. Second body; 242. Second pole; 25. Explosion-proof valve; 26. Liquid injection hole; 27. First weld mark; 28. Second weld mark; 29. ​​Sealing ring. Modes for Carrying Out the Invention

[0077] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0078] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0079] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0080] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0081] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0082] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0083] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0084] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0085] Batteries are widely used in electrical 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.

[0086] Research has found that during battery use, internal short circuits and other factors can cause a sudden increase in battery current, which can damage electrical equipment. Therefore, improving battery safety is an urgent issue to be addressed.

[0087] To address the aforementioned issues, after in-depth research, a battery cell was designed, comprising a housing, an electrode assembly, and a first electrode terminal. The electrode assembly is disposed within the housing and includes a first tab and a second tab. The first electrode terminal includes a first body and a first post protruding from one side of the first body. The first post extends through the sidewall of the housing. The first body is disposed within the housing and electrically connected to the first tab. At least one of the first body and the first post includes a fuse, the flow area of ​​which is smaller than that of its adjacent region. The fuse on the first electrode terminal can melt when the current exceeds a threshold, discontinuing the battery cell's power supply. This protects the battery cell and the circuit in which it resides, reducing the probability of overcurrent damage to the battery cell and electrical equipment. Blowing the fuse also reduces the probability of thermal runaway, improving the safety of the battery cell.

[0088] The battery cells provided in the embodiments of the present application can be used in electrical devices that use batteries as power sources. The electrical devices may include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, and the like. Among them, electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0089] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0090] Please refer to Figure 1, which is a schematic structural diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0091] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0092] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of the present application. In some embodiments, the battery 100 includes a housing 10 and a battery cell 20, wherein the battery cell 20 is accommodated in the housing 10.

[0093] The box body 10 is used to provide a storage space for the battery cells, and the box body 10 can adopt a variety of structures. In some embodiments, the box body 10 may include a first part 11 and a second part 12, and the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cells. The second part 12 can be a hollow structure with one end open, and the first part 11 can be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box body 10 formed by the first part 11 and the second part 12 can be a variety of shapes, such as a cylinder, a cuboid, etc.

[0094] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection to form a battery module, which is then connected in series, in parallel, or in a hybrid connection to form a complete battery module, and then housed within the housing 10. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0095] Each battery cell 20 may be a secondary battery or a primary battery, and may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0096] The first embodiment of the present application provides a battery cell 20. Referring to Figures 3 to 6 , the battery cell 20 includes a housing 21, an electrode assembly 22, and a first electrode terminal 23. The electrode assembly 22 is disposed within the housing 21 and includes a first electrode tab 221 and a second electrode tab 222. The first electrode terminal 23 includes a first body 231 and a first post 232 protruding from one side of the first body 231. The first post 232 extends through the sidewall 211 of the housing 21. The first body 231 is disposed within the housing 21 and is electrically connected to the first electrode tab 221. At least one of the first body 231 and the first post 232 has a fuse 233, and the flow area of ​​the fuse 233 is smaller than the flow area of ​​its adjacent region.

[0097] The outer shell 21 is an element used to form the internal environment of the battery cell 20. The internal environment formed by the outer shell 21 can be used to accommodate the electrode assembly 22, electrolyte and other components. The outer shell 21 may include a shell with an open end and an end cover provided on the shell, or it may be an integrally molded structure. The outer shell 21 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the outer shell 21 can be determined according to the specific shape and size of the electrode assembly 22. The material of the outer shell 21 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0098] The electrode assembly 22 is the component in the battery cell 20 where the electrochemical reaction occurs. One or more electrode assemblies 22 may be contained within the housing 21. The electrode assembly 22 is primarily formed by winding or stacking positive and negative electrode sheets, and a separator is typically provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly 22, while the portions of the positive and negative electrode sheets without active material each constitute a tab. One of the first tab 221 and the second tab 222 is a positive tab, and the other is a negative tab.

[0099] In the embodiment of the present application, the first electrode terminal 23 can be either a negative electrode terminal or a positive electrode terminal. The first electrode terminal 23 includes a first body 231 and a first post 232 protruding from one side of the first body 231. The first post 232 extends through the housing 21. Specifically, a post lead-out hole is provided on the sidewall 211 of the housing 21, and the first post 232 extends through the post lead-out hole. The first post 232 is used to electrically connect to external electrical components.

[0100] The first body 231 is disposed in the housing 21 and is electrically connected to the first tab 221. The first body 231 can be directly welded to the first tab 221 to achieve electrical connection, or can be electrically connected to the first tab 221 through an adapter.

[0101] Optionally, the first pole 232 may be, but is not limited to, cylindrical, and the first body 231 may be, but is not limited to, flat. For example, the first body 231 may be a rectangular flat plate. The first pole 232 may be integrally provided with the first body 231, or the first pole 232 may be separately provided with the first body 231 and fixedly connected.

[0102] At least one of the first body 231 and the first terminal 232 includes a fuse 233. The flow area of ​​the fuse 233 is smaller than the flow area of ​​its adjacent areas. When an overcurrent occurs, the fuse 233, due to its smaller flow area and higher resistance, generates a high temperature and melts, disconnecting the battery. As shown in Figure 5, in some embodiments, the fuse 233 is located on the first terminal 232, and the flow area of ​​the fuse 233 is smaller than the flow area of ​​the area adjacent to the fuse 233 on the first terminal 232. In other embodiments, the fuse 233 may also be located on the first body 231, and the flow area of ​​the fuse 233 is smaller than the flow area of ​​the area adjacent to the fuse 233 on the first body 231. The flow area of ​​the fuse refers to the cross-sectional area of ​​the fuse 233 that allows current to flow, while the flow area of ​​the area adjacent to the fuse 233 refers to the cross-sectional area of ​​the area adjacent to the fuse 233 that allows current to flow. Taking the cross section of the fuse part 233 as a circle as an example, the flow area of ​​the fuse part 233 is the area of ​​the circular cross section; taking the cross section of the fuse part 233 as a rectangle as an example, the flow area of ​​the fuse part 233 is the area of ​​the rectangular cross section.

[0103] The fuse 233 functions as a normal electrical connection when the current passing through the first electrode terminal 23 is less than a threshold value, allowing the battery to be properly connected to the circuit. The threshold value is defined as the upper limit of the current at which the fuse 233 will not blow. When the current of the battery cell 20 exceeds the threshold value, the fuse 233 melts and disconnects, and the battery cell 20 stops supplying power. This protects the battery cell 20 and the circuit in which it resides, reduces the probability of overcurrent damage to the battery cell 20 and the electrical equipment, and improves the safety of the battery cell 20 and the electrical equipment. At the same time, after the fuse 233 blows, thermal runaway is prevented to a certain extent, and the short-circuited battery cell 20 is prevented from damaging the remaining battery cells 20, thereby protecting the battery and the electrical equipment.

[0104] The battery cell 20 provided in the embodiment of the present application includes a shell 21, an electrode assembly 22 and a first electrode terminal 23. The first electrode terminal 23 includes a first body 231 and a first pole 232 protruding from one side of the first body 231. At least one of the first body 231 and the first pole 232 has a fuse part 233. The flow area of ​​the fuse part 233 is smaller than the flow area of ​​its adjacent area. Therefore, the fuse part 233 on the first electrode terminal 23 can be melted when the current exceeds the threshold, and the battery cell 20 no longer continues to supply power to protect the battery cell 20 and the circuit in which it is located, and reduce the probability of overcurrent damage to the battery cell 20 and the electrical equipment; the melting of the fuse part 233 can also reduce the probability of thermal runaway, thereby improving the safety of the battery cell 20.

[0105] 5 and 6 , in some embodiments, the first body 231 and / or the first pole 232 has a groove 2331 , and the position of the groove 2331 forms the fuse portion 233 .

[0106] For example, the fuse 233 is provided on the first terminal 232, and the groove 2331 is provided on the surface of the first terminal 232. By providing the groove 2331 on the surface of the fuse 233, the flow area of ​​the fuse 233 can be reduced, making the flow area of ​​the fuse 233 smaller than the flow area of ​​its adjacent areas. At the same time, the groove 2331 is relatively simple to manufacture and easy to implement.

[0107] It can be understood that in other embodiments, the groove 2331 is not limited to being recessed in the surface of the fuse part 233 . For example, the groove 2331 can also be provided inside the fuse part 233 .

[0108] As shown in FIG. 6 , in some embodiments, the fuse portion 233 is provided on the first pole 232 , and the groove 2331 is provided on the peripheral wall of the first pole 232 .

[0109] The first pole 232 is cylindrical, and a groove 2331 is provided on the circumferential wall of the first pole 232 to reduce the flow area of ​​the fuse 233. Optionally, there may be one groove 2331; in other embodiments, there may be multiple grooves 2331, which are spaced apart along the circumference of the first pole 232.

[0110] By adopting the above technical solution, the groove 2331 is arranged on the peripheral wall of the first pole 232, and the flow area of ​​the fuse part 233 is small. When the current passing through the battery cell 20 exceeds the threshold value, the first pole 232 can be melted at the fuse part 233; and the groove 2331 is arranged on the peripheral wall of the first pole 232, that is, on the outer surface of the first pole 232, and the manufacturing method is relatively simple.

[0111] In some embodiments, the groove 2331 is an annular groove disposed around the peripheral wall of the first pole 232 .

[0112] The groove 2331 is arranged around the peripheral wall of the first pole 232, that is, the groove 2331 is an annular groove. In this way, the groove 2331 is easy to manufacture; by providing the annular groove around the first pole 232, the flow area of ​​the fuse 233 can be effectively reduced.

[0113] In other embodiments, the groove 2331 may also be an arc-shaped groove, which is provided along a portion of the circumferential wall of the first pole 232 .

[0114] 5 and 6 , in some embodiments, along the axial direction of the first pole 232 , the first pole 232 includes a first column portion 2321 and a second column portion 2322 respectively provided at both ends of the fuse portion 233 ; the first electrode terminal 23 also includes a first insulating structure 234 accommodated in the groove 2331 , and the first insulating structure 234 is fixedly connected to at least one of the first column portion 2321 and the second column portion 2322 .

[0115] Two ends of the first insulating structure 234 are respectively connected to the first column portion 2321 and the second column portion 2322 . It is understandable that the first insulating structure 234 may also be connected only to the first column portion 2321 or the second column portion 2322 .

[0116] Please refer to Figures 5 to 9 at the same time. An electrode lead-out hole is provided on the side wall 211 of the outer shell 21. The first pole 232 is inserted into the electrode lead-out hole, and a sealing ring 29 is provided in the electrode lead-out hole. The sealing ring 29 is sleeved on the circumference of the first pole 232 and is used to seal the electrode lead-out hole to prevent leakage of the electrolyte in the electrode assembly 22; the sealing ring 29 is also sleeved on the circumference of the first insulating structure 234.

[0117] When the fuse part 233 melts, the first column part 2321 and the second column part 2322 will separate. Since the first insulating structure 234 is still connected to the first column part 2321 and / or the second column part 2322, the first insulating structure 234 can maintain contact with the sealing ring 29, and the electrolyte is not likely to leak quickly and in large quantities.

[0118] In some embodiments, the first insulating structure 234 is a plastic component, and the first insulating structure 234 and the first pole 232 are integrally formed.

[0119] The first insulating structure 234 can be made of plastic. The first insulating structure 234 and the first pole 232 are manufactured by integral molding, so that the first insulating structure 234 can be fixedly connected to the first column portion 2321 and the second column portion 2322 by a buckle or other structure.

[0120] Referring to Figures 10 to 15 , other embodiments of the present application provide a battery cell 20 comprising a housing 21, an electrode assembly 22, and a first electrode terminal 23. The electrode assembly 22 is disposed within the housing 21 and includes a first electrode tab 221 and a second electrode tab 222. The first electrode terminal 23 includes a first body 231 and a first post 232 protruding from one side of the first body 231. The first post 232 extends through a sidewall 211 of the housing 21. The first body 231 is disposed within the housing 21 and is electrically connected to the first electrode tab 221. In some embodiments, the first body 231 has a fuse 233.

[0121] Optionally, the first body 231 includes a first connecting portion 2311 and a second connecting portion 2312, and the first connecting portion 2311 and the second connecting portion 2312 are connected along the arrangement direction (first direction X) of the first pole ear 221 and the second pole ear 222, and the first connecting portion 2311 is used to electrically connect the first pole ear 221; the fuse portion 233 is arranged between the first connecting portion 2311 and the second connecting portion 2312.

[0122] The first body 231 can be in the shape of a flat plate, for example, a roughly rectangular plate. The first connecting portion 2311 is used to electrically connect to the first electrode tab 221. The first connecting portion 2311 can be directly welded to the first electrode tab 221 or connected to the first electrode tab 221 via an adapter. The first electrode post 232 is disposed on the second connecting portion 2312. The fuse portion 233 is disposed between the first connecting portion 2311 and the second connecting portion 2312. The flow area of ​​the fuse portion 233 is smaller than that of the first connecting portion 2311 and the second connecting portion 2312. When the current in the electrode assembly 22 exceeds a threshold, the fuse portion 233 will melt, thereby disconnecting the electrical connection between the battery and the electrical device.

[0123] By adopting the above technical solution, the fuse part 233 is provided on the first body 231, which can also play a role of fusing, thereby improving the safety of the battery and the electrical equipment.

[0124] In some embodiments, a groove 2331 is provided on the surface of the first body 231 facing away from the first tab 221 , and the position of the groove 2331 forms the fuse portion 233 .

[0125] The groove 2331 may be, but is not limited to, a strip-shaped groove. For example, the groove 2331 may also be an arc-shaped groove or a groove 2331 of other shapes.

[0126] By adopting the above technical solution, the groove 2331 is recessed on the surface of the first body 231 away from the first tab 221 . Thus, the surface of the groove 2331 close to the first tab 221 can still be conveniently welded to the first tab 221 .

[0127] In another embodiment, the grooves 2331 may also be disposed on two opposite surfaces of the first body 231 .

[0128] In some embodiments, the first electrode tab 221 is welded to the first connecting portion 2311 , and a second insulating structure 235 is disposed between the second connecting portion 2312 and the first electrode tab 221 .

[0129] The first tab 221 is welded to the first connecting portion 2311, thereby electrically connecting the first tab 221 to the first connecting portion 2311. One end of the first tab 221 may extend to the second connecting portion 2312. It is understood that the first tab 221 may not extend to the second connecting portion 2312. The second insulating structure 235 can electrically insulate the first tab 221 from the second connecting portion 2312. Thus, after the fuse portion 233 is blown, the first tab 221 will not transmit current to the second connecting portion 2312.

[0130] In some embodiments, the second insulating structure 235 is at least one of insulating tape, insulating coating, and insulating colloid.

[0131] The second insulating structure 235 can be an insulating sticker directly attached to the second connecting part 2312; the second insulating structure 235 can also be an insulating coating directly sprayed on the second connecting part 2312; the second insulating structure 235 can also be an insulating colloid made on the second connecting part 2312 by dispensing.

[0132] By adopting the above technical solution, the manufacturing method of the second insulating structure 235 is simple, flexible and convenient, and the manufacturing efficiency is high.

[0133] In some embodiments, the flow area of ​​the fuse portion 233 is greater than or equal to ⅔ of the flow area of ​​the second electrode tab 222 .

[0134] On the one hand, the flow area of ​​the fuse 233 is smaller than the flow area of ​​the second tab 222; on the other hand, the flow area of ​​the fuse 233 is greater than or equal to two-thirds of the flow area of ​​the second tab 222. In this way, by setting the flow area of ​​the fuse 233, the fuse 233 can be caused to melt under preset conditions to meet usage requirements.

[0135] 3 , in some embodiments, the second electrode tab 222 includes multiple layers of stacked second electrode tab sheets. The flow area of ​​the second electrode tab 222 is equal to the product of the width W5 of the second electrode tab sheet, the number of layers X of the second electrode tab sheet, and the thickness T of the second electrode tab sheet. That is, the flow area of ​​the second electrode tab 222 is W5*X*T.

[0136] The flow area of ​​the fuse portion 233 is related to the shape and size of the fuse portion 233 .

[0137] 5 , when the fuse 233 is provided on the first pole 232 and the diameter of the fuse 233 is W6, the flow area of ​​the fuse 233 satisfies the following condition: π*(W6 / 2) 2 ≥2 / 3*W5*X*T.

[0138] 10 to 12 , when the fuse portion 233 is disposed on the first body 231 , the length of the fuse portion 233 along the first direction X is L1 , and the thickness of the fuse portion 233 is L2 . The flow area of ​​the fuse portion 233 satisfies the following condition: L1*L2≥2 / 3*W5*X*T.

[0139] The thickness L2 of the fuse portion 233 is smaller than the thickness of the first body 231 , and is the remaining thickness of the fuse portion 233 after removing the groove 2331 .

[0140] By adopting the above technical solution, the flow area of ​​the second tab 222 can be calculated in the above manner to determine the flow area of ​​the fuse 233 based on the flow area of ​​the second tab 222 and further determine the size of the fuse 233 .

[0141] In some embodiments, the first electrode tab 221 is a positive electrode tab, and the first electrode terminal 23 is a positive electrode terminal.

[0142] The first electrode terminal 23 is the positive electrode terminal, and the second electrode terminal 24 is the negative electrode terminal. Optionally, the first electrode terminal 23 has a lower melting point than the second electrode terminal 24. In this way, the fuse 233 is arranged on the positive electrode terminal, which makes it easier to achieve the fuse condition, making the battery cell 20 safer.

[0143] In some embodiments, the first body 231 and the first pole 232 of the first electrode terminal 23 can be offset. Referring to Figures 3 to 9, the first body 231 includes a first side surface 231a and a second side surface 231b that are oppositely disposed along a first direction X. The distance between the first side surface 231a and the first pole 232 is greater than the minimum distance between the second side surface 231b and the first pole 232. The first direction X is the arrangement direction of the first tab 221 and the second tab 222.

[0144] The first side surface 231 a and the second side surface 231 b may be perpendicular to the first direction X. It is understood that the first side surface 231 a and the second side surface 231 b may also be arranged obliquely relative to the first direction X. FIG6 illustrates a distance D1 between the first side surface 231 a and the first pole 232 , and a second distance D2 between the second side surface 231 b and the first pole 232 , where D1 is greater than D2.

[0145] In this embodiment, the first side surface 231a is the surface of the first body 231 close to the middle of the housing 21, and the second side surface 231b is the surface of the first body 231 close to the outside of the housing 21. That is, the first body 231 is offset inward relative to the first pole 232. In this way, the inwardly offset portion of the first body 231 can be easily welded to the first tab 221, improving the welding quality and facilitating a larger offset space for the first tab 221. At the same time, the other side of the first body 231 can reserve a space for evacuation to facilitate the installation of other structural components, such as a pressure strip.

[0146] 10 to 15 , in some embodiments, the first body 231 is offset inward relative to the first pole 232. Optionally, the second electrode terminal 24 is also eccentric and offset inward.

[0147] In other embodiments, the first body 231 may also be disposed outwardly relative to the first pole 232 .

[0148] By adopting the above technical solution, the first body 231 and the first pole 232 of the first electrode terminal 23 can be offset, and a certain avoidance space can be reserved for the first body 231, which is beneficial to the arrangement of components inside the battery cell 20.

[0149] Please refer to Figures 3 to 8, 10, and 14 to 15, where Figure 15 illustrates the length W2 of the sidewall 211 and the center-to-center distance W3 of the electrode posts. In some embodiments, the battery cell 20 further includes a second electrode terminal 24, which includes a second body 241 and a second electrode post 242 protruding from one side of the second body 241. The second electrode post 242 extends through the sidewall 211 of the outer shell 21. The second body 241 is disposed within the outer shell 21 and is electrically connected to the second electrode tab 222. The center-to-center distance W1 between the first electrode tab 221 and the second electrode tab 222 is less than the center-to-center distance W3 between the first electrode post 232 and the second electrode post 242. The first electrode tab 221 has an offset space within the battery cell 20, and the length W4 of the offset space is greater than or equal to 8 mm. The length W4 of the dislocation space refers to the length of the dislocation space along the first direction X. Since the first pole tab 221 includes multiple pole tabs, the arrangement of the multiple pole tabs may be dislocated. The battery cell provided in this embodiment can allow multiple pole tabs to be dislocated in the dislocation space.

[0150] The battery cell 20 is further provided with a liquid injection hole 26 and an explosion-proof valve 25 . The explosion-proof valve 25 is provided in the middle of the battery cell 20 , and the liquid injection hole 26 is provided between the explosion-proof valve 25 and the first electrode terminal 23 .

[0151] The second body 241 of the second electrode terminal 24 is offset inward relative to the second electrode post 242. The second body 241 is welded to the second electrode tab 222, and the first body 231 is welded to the first electrode tab 221. Because both the second body 241 and the first body 231 are offset inward relative to the battery cell 20, when the center-to-center distance between the electrode posts is small, the first and second electrode tabs 221 and 222 can both have a large offset space (Figure 3 illustrates the tab offset line 221a of the first electrode tab 221). This allows the length W4 of the offset space of the first electrode tab 221 to be greater than or equal to 8 mm. Correspondingly, the length of the offset space of the second electrode tab 222 is also greater than or equal to 8 mm. It will be understood that the offset space of the first electrode tab 221 is related to the length of the electrode assembly 22. The longer the electrode assembly 22, the larger the offset space of the first electrode tab 221.

[0152] By adopting the above technical solution, the first body 231 is arranged inwardly relative to the first pole 232 , and the first pole tab 221 has a larger staggered arrangement space.

[0153] 7 and 14 , in some embodiments, the second side surface 231 b is closer to the edge of the housing 21 than the first side surface 231 a ; the first tab 221 has a first weld mark 27 , and the projection of the first weld mark 27 toward the first body 231 completely falls within the first body 231 .

[0154] The first side surface 231a is closer to the interior of the housing 21 than the second side surface 231b, and the distance between the first side surface 231a and the first pole 232 is greater than the minimum distance between the second side surface 231b and the first pole 232, that is, the first body 231 is offset toward the inside of the battery cell 20.

[0155] The first electrode tab 221 includes multiple electrode tab sheets, which are ultrasonically welded to form a first weld mark 27. The first weld mark 27 falls within the range of the first body 231, that is, along the first direction X, the distance between the first weld mark 27 and the edge of the first body 231 is greater than or equal to 0 mm, and along the second direction Y, the distance between the first weld mark 27 and the edge of the first body 231 is greater than or equal to 0 mm.

[0156] By adopting the above technical solution, the first electrode tab 221 can be arranged corresponding to the first body 231 to facilitate welding, and can also prevent the laser welding head from directly pressing on the first electrode tab 221 during laser welding and crushing or cracking the first electrode tab 221.

[0157] In some embodiments, along the first direction X, the distance H1 between the first weld mark 27 and the edge of the first body 231 is greater than or equal to 1 mm; and / or, along the second direction Y perpendicular to the first direction X, the distance H2 between the first weld mark 27 and the edge of the first body 231 is greater than or equal to 1 mm.

[0158] The first direction X is the length direction of the housing 21 , and is also the arrangement direction of the first electrode tabs 221 and the second electrode tabs 222 ; the second direction Y is the width direction of the housing 21 .

[0159] By adopting the above technical solution, the first weld mark 27 can be completely placed inside the first body 231 .

[0160] In some embodiments, the first tab 221 is welded to the first body 231 to form a second weld mark 28 , and a ratio of a thickness of the first body 231 to a thickness of the first tab 221 is greater than or equal to 3.

[0161] After the first electrode tab 221 is laser welded, the first electrode tab 221 and the first body 231 need to be welded to form a second weld mark 28 . For example, the first electrode tab 221 and the first body 231 are laser welded to form a laser weld mark.

[0162] The ratio of the thickness of the first body 231 to the thickness of the first tab 221 is greater than or equal to 3, so that the thickness of the first body 231 is greater than the laser welding penetration depth, and the first body 231 is not easily penetrated during welding.

[0163] A second aspect of the present application provides a battery 100 , comprising the battery cell 20 provided in the first aspect.

[0164] A third aspect of the present application provides an electrical device, comprising the battery 100 provided in the second aspect, wherein the battery 100 is used to provide electrical energy to the electrical device.

[0165] The electrical device may be any of the aforementioned devices or systems using batteries.

[0166] It should be noted that, unless there is any conflict, the features in the embodiments of this application can be combined with each other.

[0167] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A battery cell, characterized in that: include: shell; An electrode assembly, disposed in the housing and comprising a first electrode tab and a second electrode tab; A first electrode terminal, comprising a first body and a first pole protruding from one side of the first body, wherein the first pole is passed through the shell, and the first body is disposed in the shell and is electrically connected to the first pole tab; At least one of the first body and the first pole has a fuse portion, and a flow area of ​​the fuse portion is smaller than a flow area of ​​an adjacent region thereof.

2. The battery cell according to claim 1, characterized in that: The first body and / or the first pole has a groove, and the position of the groove forms the fuse.

3. The battery cell according to claim 2, characterized in that: The fuse part is arranged on the first pole, and the groove is arranged on the peripheral wall of the first pole.

4. The battery cell according to claim 3, characterized in that: The groove is an annular groove arranged around the peripheral wall of the first pole.

5. The battery cell according to claim 3 or 4, characterized in that: Along the axial direction of the first pole, the first pole includes a first column portion and a second column portion respectively arranged at two ends of the fuse portion; The first electrode terminal further includes a first insulating structure received in the groove, wherein the first insulating structure is fixedly connected to at least one of the first column portion and the second column portion.

6. The battery cell according to claim 5, characterized in that: The first insulating structure is a plastic part and is integrally formed with the first pole.

7. The battery cell according to any one of claims 3 to 6, characterized in that: The flow area of ​​the fuse portion is greater than or equal to 2 / 3 of the flow area of ​​the second electrode tab.

8. The battery cell according to claim 7, characterized in that: The flow area of ​​the fuse part satisfies: π*(W6 / 2) 2 ≥2 / 3*W5*X*T; The second pole tab includes a plurality of stacked second pole tab sheets, W5 is the width of the second pole tab sheet, X is the number of layers of the second pole tab sheet, T is the thickness of the second pole tab sheet; and W6 is the diameter of the fuse portion.

9. The battery cell according to claim 1, characterized in that: The first body includes a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion are connected along an arrangement direction of the first pole tab and the second pole tab, and the first connecting portion is used to electrically connect the first pole tab; The fuse portion is disposed between the first connection portion and the second connection portion.

10. The battery cell according to claim 9, characterized in that: A groove is provided on the surface of the first body facing away from the first electrode tab, and the position of the groove forms the fuse part.

11. The battery cell according to claim 9 or 10, characterized in that: The first pole tab is welded to the first connecting portion, and a second insulating structure is provided between the second connecting portion and the first pole tab.

12. The battery cell according to claim 11, characterized in that: The second insulating structure is at least one of insulating adhesive tape, insulating coating, and insulating colloid.

13. The battery cell according to any one of claims 9 to 12, characterized in that: The flow area of ​​the fuse portion is greater than or equal to 2 / 3 of the flow area of ​​the second electrode tab.

14. The battery cell according to claim 13, characterized in that: The area of ​​the fuse part satisfies: L1*L2≥2 / 3*W5*X*T; The second pole ear includes a plurality of stacked second pole ear sheets, W5 is the width of the second pole ear sheet, X is the number of layers of the second pole ear sheet, and T is the thickness of the second pole ear sheet; L1 is the length of the fuse portion along a first direction, the first direction is the arrangement direction of the first pole ear and the second pole ear, and L2 is the thickness of the fuse portion.

15. The battery cell according to any one of claims 1 to 14, characterized in that: The first electrode tab is a positive electrode tab, and the first electrode terminal is a positive electrode terminal.

16. The battery cell according to any one of claims 1 to 14, characterized in that: The first body includes a first side surface and a second side surface arranged opposite to each other along a first direction, the distance between the first side surface and the first pole is greater than the minimum distance between the second side surface and the first pole, and the first direction is the arrangement direction of the first pole lug and the second pole lug.

17. The battery cell according to claim 16, characterized in that: The battery cell further includes a second electrode terminal, the second electrode terminal includes a second body and a second pole protruding from one side of the second body, the second pole is passed through the shell, and the second body is disposed in the shell and is electrically connected to the second pole tab; The center distance between the first pole lug and the second pole lug is smaller than the center distance between the first pole post and the second pole post. The first pole lug has a misalignment space in the battery cell, and the length of the misalignment space is greater than or equal to 8 mm.

18. The battery cell according to claim 16 or 17, characterized in that: The second side surface is closer to the edge of the housing than the first side surface; The first electrode tab has a first weld mark, and a projection of the first weld mark toward the first body completely falls within the first body.

19. The battery cell according to claim 18, characterized in that: Along the first direction, the distance between the first weld mark and the edge of the first body is greater than or equal to 1 mm; and / or, Along a second direction perpendicular to the first direction, a distance between the first weld mark and an edge of the first body is greater than or equal to 1 mm.

20. The battery cell according to any one of claims 16 to 19, characterized in that: The first pole tab is welded to the first body to form a second weld mark, and a ratio of a thickness of the first body to a thickness of the first pole tab is greater than or equal to 3.

21. A battery, characterized in that: The invention comprises a battery cell end cover as claimed in any one of claims 1 to 20.

22. An electrical equipment, characterized in that: Comprising the battery as claimed in claim 21, wherein the battery is used to provide electrical energy to the electrical device.

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