Battery cell, battery apparatus and electrical apparatus

Abstract

Provided in the present application are a battery cell, a battery apparatus and an electrical apparatus. An electrode terminal of the battery cell is arranged on a wall portion of a casing, and an electrode assembly is accommodated in the casing, the electrode assembly comprising a first tab and a second tab having opposite polarities. A current collector is located between an inner wall of the casing and the electrode assembly, a first connecting portion and a second connecting portion of the current collector are spaced apart, and a fusing portion is connected between the first connecting portion and the second connecting portion. The first connecting portion is connected to the second tab, the second connecting portion is connected to the inner wall of the casing, and the fusing portion is configured to be able to disconnect the connection between the first connecting portion and the second connecting portion. When a short circuit occurs in the battery cell and overcurrent occurs in the fusing portion, the fusing portion will disconnect the connection between the first connecting portion and the second connecting portion because the temperature exceeds a first threshold, and disconnect a short-circuit loop in the battery cell, such that the battery cell has relatively high reliability, thus helping to improve the reliability of the battery apparatus.

Description

Battery cells, battery packs and electrical devices Cross-references to related applications

[0001] This application claims priority to Chinese patent application 202411539845.8, filed on October 31, 2024, entitled “Battery cell, battery device and power supply device”, the entire contents of which are incorporated herein by reference. Technical Field

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

[0003] Battery devices have advantages such as high specific energy and high power density, and are widely used in electronic devices and transportation vehicles, such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships and power tools.

[0004] As the application scope of battery devices continues to expand, the requirements for their reliability are also increasing. How to improve the reliability of battery devices is receiving increasing attention from those skilled in the art. Summary of the Invention

[0005] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device. The battery cell has high reliability, which is beneficial to improving the reliability of the battery device.

[0006] In a first aspect, some embodiments of this application provide a battery cell, which includes a casing, electrode terminals, an electrode assembly, and a current collector. The casing includes a wall portion; the electrode terminals are disposed in the wall portion; the electrode assembly is housed in the casing, and the electrode assembly includes an electrode body and a first tab and a second tab extending from the electrode body and having opposite polarities, the first tab being electrically connected to the electrode terminal; the current collector is located between the inner wall of the casing and the electrode assembly, and the current collector includes a first connecting portion, a second connecting portion, and a fuse portion, the first connecting portion and the second connecting portion being arranged at intervals, the fuse portion being connected between the first connecting portion and the second connecting portion, the first connecting portion being connected to the second tab, the second connecting portion being connected to the inner wall of the casing, and the fuse portion being configured to cut off the connection between the first connecting portion and the second connecting portion.

[0007] In the above structure, since the fuse connected between the first connection part and the second connection part is configured to cut off the connection between the first connection part and the second connection part, causing a short circuit inside the battery cell, when the fuse part experiences overcurrent, the fuse part will cut off the connection between the first connection part and the second connection part due to the temperature exceeding the first threshold, cutting off the circuit of the short circuit inside the battery cell, reducing the possibility of the battery cell catching fire or exploding, making the battery cell more reliable, which is beneficial to improving the reliability of the battery device.

[0008] According to some embodiments of the present application, the battery cell has a throttling orifice in the fuse portion. The throttling orifice penetrates the fuse portion along its thickness direction to form a fuse structure. The fuse structure is connected between a first connecting portion and a second connecting portion and is configured to cut off the connection between the first connecting portion and the second connecting portion. By penetrating the fuse portion along its thickness direction, the throttling orifice forms a fuse structure with a small current-carrying area on the fuse portion, allowing the current flowing through the fuse structure to generate more heat. This enables the temperature of the fuse structure to rise rapidly when an overcurrent occurs in the fuse portion, thereby achieving fuse breaking.

[0009] According to some embodiments of this application, the battery cell has at least two throttling orifices, which are spaced apart on the fuse portion, and the fuse structure is formed between two adjacent throttling orifices. By providing at least two throttling orifices on the fuse portion, the current flow area on the fuse portion can be better reduced. By spaced apart on the fuse portion, one or at least two fuse structures can be provided between the first connecting portion and the second connecting portion, allowing the current to flow through the fuse portion more uniformly.

[0010] According to some embodiments of this application, the current collector of the battery cell includes a first insulating structure, which covers the fusible structure. The melting point of the first insulating structure is lower than that of the fusible structure, so that when the fusible structure melts, the first insulating structure can melt and fill the broken part of the fusible structure. This allows the melted material of the first insulating structure to continuously disconnect the electrical connection between the first connection and the second connection, effectively reducing the possibility of the first connection and the second connection reconnecting and improving the reliability of the battery cell.

[0011] According to some embodiments of the present application, the battery cell has a first insulating structure filling the throttling orifice, such that the first insulating structure has a sufficient amount to fill the disconnected portion of the fusible structure, thereby improving the effect of the first insulating structure in reducing the possibility of reconnection of the first connection portion and the second connection portion.

[0012] According to some embodiments of the present application, the surface of the first connecting portion facing the electrode assembly is closer to the electrode assembly than the surface of the fuse portion facing the electrode assembly, so that the surface of the first connecting portion facing the electrode assembly can be closer to the second tab, and the second tab can be more easily connected to the first connecting portion.

[0013] According to some embodiments of the present application, the battery cell provided has a distance L1 along the thickness direction of the first connecting part from the surface of the electrode assembly facing the electrode assembly, where 0.4mm≤L1≤1.2mm. This not only allows the surface of the first connecting part facing the electrode assembly to get closer to the second tab, facilitating the connection between the first connecting part and the second tab, but also prevents the surface of the first connecting part facing the electrode assembly from protruding too much from the surface of the fuse part facing the electrode assembly, reducing the space occupied by the current collector between the inner wall of the housing and the electrode assembly.

[0014] According to some embodiments of this application, the current collector includes a first insulating structure that covers the fused portion. The surface of the first insulating structure facing the electrode assembly is flush with the surface of the first connecting portion facing the electrode assembly, so that the first insulating structure can act on the electrode assembly together with the first connecting portion, thereby increasing the surface area of ​​the current collector facing the electrode assembly and improving the convenience and stability of the current collector during installation.

[0015] According to some embodiments of the present application, the surface of the second connecting portion facing the inner wall of the housing is closer to the inner wall of the housing than the surface of the fuse portion facing the inner wall of the housing, so that the surface of the second connecting portion facing the inner wall of the housing can be closer to the inner wall of the housing, and the inner wall of the housing can be more easily connected to the second connecting portion.

[0016] According to some embodiments of the present application, in the battery cell, along the thickness direction of the second connection portion, the distance by which the surface of the second connection portion facing the inner wall of the outer casing protrudes beyond the surface of the fuse portion facing the inner wall of the outer casing is L2, where 0.4mm≤L2≤1.2mm. This not only allows the surface of the second connection portion facing the inner wall of the outer casing to be closer to the inner wall of the outer casing, facilitating the connection between the second connection portion and the inner wall of the outer casing, but also prevents the surface of the second connection portion facing the inner wall of the outer casing from protruding excessively beyond the surface of the inner wall of the outer casing, reducing the space occupied by the current collector between the inner wall of the outer casing and the electrode assembly.

[0017] According to some embodiments of this application, the current collector includes a first insulating structure that covers the fusible portion. The surface of the first insulating structure facing the inner wall of the housing is flush with the surface of the second connecting portion facing the inner wall of the housing, so that the first insulating structure can act together with the second connecting portion on the inner wall of the housing, thereby increasing the surface area of ​​the current collector facing the inner wall of the housing and improving the convenience and stability of the current collector during installation.

[0018] According to some embodiments of this application, the current collector includes a second insulating structure. The second insulating structure is disposed on the surface of the first connecting portion away from the electrode assembly and is flush with the surface of the first insulating structure facing the inner wall of the housing. This makes the surface of the second insulating structure facing the inner wall of the housing, the surface of the first insulating structure facing the inner wall of the housing, and the surface of the first connecting portion away from the electrode assembly flush, further increasing the area of ​​the surface of the current collector facing the inner wall of the housing, which is beneficial to improving the convenience and stability of the current collector during installation.

[0019] According to some embodiments of this application, the second insulating structure and the first insulating structure are integrally formed in the battery cell.

[0020] According to some embodiments of the present application, the battery cell has a second insulating structure with a notch that penetrates the second insulating structure along the thickness direction of the first connecting portion. The second electrode is welded to the area of ​​the first connecting portion corresponding to the notch in the thickness direction of the first connecting portion, so that the welding equipment can weld from the notch, so that the second electrode can be welded to the area of ​​the first connecting portion corresponding to the notch in the thickness direction of the first connecting portion.

[0021] According to some embodiments of this application, the battery cell has a second connecting portion with a first through hole extending through the thickness direction, and the outer casing has a liquid injection hole that connects the interior of the outer casing with the outside. The liquid injection hole is connected to the first through hole. The battery cell also includes a cover, which is connected to the outer casing and covers the liquid injection hole.

[0022] According to some embodiments of this application, the battery cell has a pressure relief structure in its cover. By integrating the pressure relief structure into the cover, the number of components in the battery cell can be reduced, which helps to simplify the structure of the battery cell.

[0023] According to some embodiments of this application, the battery cell includes a cover and a housing. The housing forms a cavity with an opening. The housing includes an integrally formed sidewall and a bottom wall. The bottom wall is disposed opposite to the opening. The cover closes to the opening. The cover includes a wall portion, an injection hole is disposed on the bottom wall, and a second connecting portion is connected to the bottom wall. By including a wall portion in the cover covering the opening, disposing the bottom wall opposite to the opening, and disposing the injection hole on the bottom wall and the second connecting portion on the bottom wall, the electrode terminals and the pressure relief structure are respectively disposed at opposite ends of the battery cell, making it less likely that the electrode terminals will be affected when the battery cell is depressurized.

[0024] According to some embodiments of this application, the battery cell has a first connecting part, a second connecting part, and a fusible part that are integrally formed.

[0025] According to some embodiments of this application, the battery cell has an electrode assembly configured as a cylindrical wound structure, and a first connecting portion and a second connecting portion configured as a concentric ring structure, with the first connecting portion located outside the second connecting portion.

[0026] According to some embodiments of this application, the battery cell has a first tab as a negative tab and a second tab as a positive tab.

[0027] Secondly, some embodiments of this application also provide a battery device, which includes a battery cell as provided by any of the above technical solutions.

[0028] Thirdly, some embodiments of this application also provide an electrical device, which includes the battery device provided by the above-described technical solution, and the battery device is used to provide electrical energy.

[0029] The technical solutions provided by the embodiments of this disclosure have at least the following beneficial effects:

[0030] Some embodiments of this application provide a battery cell, which includes a casing, electrode terminals, an electrode assembly, and a current collector. The electrode terminals are disposed on the wall of the casing, and the electrode assembly is housed in the casing. The electrode assembly includes an electrode body and a first tab and a second tab extending from the electrode body and having opposite polarities. The first tab is electrically connected to the electrode terminal. The current collector is located between the inner wall of the casing and the electrode assembly. A first connecting portion and a second connecting portion of the current collector are arranged at intervals. A fusible portion is connected between the first connecting portion and the second connecting portion. The first connecting portion is connected to the second tab, and the second connecting portion is connected to the inner wall of the casing. The fusible portion is configured to cut off the connection between the first connecting portion and the second connecting portion. In the above structure, since the fuse connected between the first connection part and the second connection part is configured to cut off the connection between the first connection part and the second connection part, causing a short circuit inside the battery cell, when the fuse part experiences overcurrent, the fuse part will cut off the connection between the first connection part and the second connection part due to the temperature exceeding the first threshold, cutting off the circuit of the short circuit inside the battery cell, reducing the possibility of the battery cell catching fire or exploding, making the battery cell more reliable, which is beneficial to improving the reliability of the battery device.

[0031] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0032] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0033] Figure 1 is a schematic diagram of the vehicle structure provided in some embodiments of this application;

[0034] Figure 2 is an exploded view of a battery device provided in some embodiments of this application;

[0035] Figure 3 is a cross-sectional view of a battery device provided in some embodiments of this application;

[0036] Figure 4 is a schematic diagram of the current collection device provided in some embodiments of this application;

[0037] Figure 5 is a cross-sectional view at point AA in Figure 4;

[0038] Figure 6 is a schematic diagram of the current collection device provided in some other embodiments of this application;

[0039] Figure 7 is a cross-sectional view of section BB in Figure 4.

[0040] In the attached diagram:

[0041] 1. Vehicle; 2. Battery unit; 3. Controller; 4. Motor; 5. Housing; 5a. First housing section; 5b. Second housing section; 5c. Storage space;

[0042] 7. Battery cells;

[0043] 8. Outer shell; 81. Wall; 82. Cover; 83. Shell; 831. Side wall; 832. Bottom wall; 8321. Injection hole; 84. Opening; 85. Cavity;

[0044] 9. Electrode terminals;

[0045] 10. Electrode assembly; 101. Electrode body; 102. First electrode tab; 103. Second electrode tab;

[0046] 11. Current collector;

[0047] 111. First connecting part; 112. Second connecting part; 1121. First through hole; 113. Fusible part; 1131. Throttling orifice; 1132. Fusible structure; 114. First insulating structure; 115. Second insulating structure; 1151. Notch;

[0048] 12. Cover; 121. Pressure relief structure. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0050] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0051] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0052] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0053] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0054] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0055] In the embodiments of this application, "parallel" includes not only the case of absolute parallelism, but also the case of approximate parallelism as commonly understood in engineering; similarly, "perpendicular" also includes not only the case of absolute perpendicularity, but also the case of approximate perpendicularity as commonly understood in engineering. For example, if the angle between two directions is 85°-90°, the two directions can be considered perpendicular; if the angle between two directions is 0°-5°, the two directions can be considered parallel.

[0056] In this application, "multiple" means two or more (including two).

[0057] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace, among other fields.

[0058] The battery device mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cell assemblies to provide higher voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0059] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0060] A battery cell can be a rechargeable battery cell, which refers to a battery cell that can be recharged after being discharged to activate the active materials and continue to be used.

[0061] Battery cells can be lithium-ion cells, sodium-ion cells, sodium-lithium-ion cells, lithium metal cells, sodium metal cells, lithium-sulfur cells, magnesium-ion cells, nickel-metal hydride cells, nickel-cadmium cells, lead-acid cells, etc.

[0062] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, helps prevent short circuits to some extent while allowing active ions to pass through.

[0063] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0064] In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0065] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0066] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0067] Gel electrolytes consist of a polymer-based electrolyte backbone network combined with an ionic liquid—lithium salt.

[0068] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0069] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0070] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphorus sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0071] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0072] In some embodiments, the electrode assembly is a wound structure. Optionally, the electrode assembly is a cylindrical wound structure.

[0073] In some embodiments, a single battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0074] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries.

[0075] In some embodiments, the battery can be a battery module, and when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0076] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cell assemblies housed within the housing.

[0077] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0078] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0079] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0080] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0081] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0082] In some embodiments, the battery device can be used in an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0083] Currently, a type of battery cell with a single-ended electrode terminal has appeared on the market. Its outer casing carries an electrical polarity opposite to that of the electrode terminals, and the two are insulated from each other by an insulating structure. However, with prolonged use and the influence of external vibrations, this battery cell poses a risk of short circuits between the electrode terminals and the casing. This is detrimental to the reliability of the battery cell and may lead to fire or explosion.

[0084] To improve the reliability of a single battery cell, some embodiments of this application provide a single battery cell including a housing, electrode terminals, an electrode assembly, and a current collector. The electrode terminals are disposed on the wall of the housing, and the electrode assembly is housed within the housing. The electrode assembly includes an electrode body and a first tab and a second tab extending from the electrode body and having opposite polarities. The first tab is electrically connected to the electrode terminal. The current collector is located between the inner wall of the housing and the electrode assembly. A first connecting portion and a second connecting portion of the current collector are arranged at intervals. A fusible portion is connected between the first connecting portion and the second connecting portion. The first connecting portion is connected to the second tab, and the second connecting portion is connected to the inner wall of the housing. The fusible portion is configured to cut off the connection between the first connecting portion and the second connecting portion. In the above structure, since the fuse connected between the first connection part and the second connection part is configured to cut off the connection between the first connection part and the second connection part, causing a short circuit inside the battery cell, when the fuse part experiences overcurrent, the fuse part will cut off the connection between the first connection part and the second connection part due to the temperature exceeding the first threshold, cutting off the circuit of the short circuit inside the battery cell, reducing the possibility of the battery cell catching fire or exploding, making the battery cell more reliable, which is beneficial to improving the reliability of the battery device.

[0085] The battery cells described in the embodiments of this application are applicable to battery devices and electrical devices that use battery devices.

[0086] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, among others. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.

[0087] For ease of explanation, the following embodiments will be described using a vehicle as an example of an electrical device according to an embodiment of this application.

[0088] Figure 1 is a schematic diagram of the structure of a vehicle provided in some embodiments of this application.

[0089] As shown in Figure 1, a battery device 2 is installed inside the vehicle 1. The battery device 2 can be located at the bottom, front, or rear of the vehicle 1. The battery device 2 can be used to power the vehicle 1; for example, the battery device 2 can serve as the operating power source for the vehicle 1.

[0090] The vehicle 1 may also include a controller 3 and a motor 4. The controller 3 is used to control the battery device 2 to supply power to the motor 4, for example, for the power needs of the vehicle 1 during starting, navigation and driving.

[0091] In some embodiments of this application, the battery device 2 can not only serve as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0092] Figure 2 is an exploded view of a battery device provided in some embodiments of this application. As shown in Figure 2, the battery device 2 includes a housing 5 and battery cells 7, with the battery cells 7 housed within the housing 5. The battery cell 7 can be the smallest unit constituting a battery.

[0093] The housing 5 is used to house the battery cell 7, and the housing 5 can have various structures. In some embodiments, the housing 5 may include a first housing portion 5a and a second housing portion 5b, which overlap each other, and together define a housing space 5c for housing the battery cell 7. The second housing portion 5b may be a hollow structure with one end open, and the first housing portion 5a may be a plate-like structure, with the first housing portion 5a covering the open side of the second housing portion 5b to form a housing 5 with the housing space 5c; alternatively, both the first housing portion 5a and the second housing portion 5b may be hollow structures with one side open, with the open side of the first housing portion 5a covering the open side of the second housing portion 5b to form a housing 5 with the housing space 5c. Of course, the first housing portion 5a and the second housing portion 5b can be various shapes, such as cylinders, cuboids, etc.

[0094] To improve the sealing performance after the first housing part 5a and the second housing part 5b are connected, a sealing element, such as sealant or sealing ring, can also be provided between the first housing part 5a and the second housing part 5b.

[0095] Assuming that the first box section 5a covers the top of the second box section 5b, the first box section 5a can also be called the upper box cover, and the second box section 5b can also be called the lower box.

[0096] In the battery device 2, there can be one or more battery cells 7. If there are multiple battery cells 7, they can be connected in series, in parallel, or in a mixed manner. A mixed connection means that multiple battery cells 7 are connected in both series and parallel. Multiple battery cells 7 can be directly connected in series, in parallel, or in a mixed manner, and then the whole assembly of multiple battery cells 7 is housed in the housing 5. Alternatively, multiple battery cells 7 can first be connected in series, in parallel, or in a mixed manner to form a battery module, and then multiple battery modules can be connected in series, in parallel, or in a mixed manner to form a whole assembly, which is then housed in the housing 5.

[0097] Multiple battery cells 7 in the battery module can be electrically connected through a busbar to achieve parallel, series, or mixed connection of multiple battery cells 7 in the battery module.

[0098] The battery cell 7 can be a cylindrical battery cell, a square battery cell, or a battery cell of other shapes.

[0099] Some embodiments of this application provide a battery cell 7, as shown in FIG3. The battery cell 7 includes a housing 8, electrode terminals 9, an electrode assembly 10 or a current collector 11. The housing 8 includes a wall portion 81; the electrode terminals 9 are disposed in the wall portion 81; the electrode assembly 10 is housed in the housing 8, and the electrode assembly 10 includes an electrode body 101 and a first electrode tab 102 and a second electrode tab 103 extending from the electrode body 101 and having opposite polarities. The first electrode tab 102 is electrically connected to the electrode terminal 9; the current collector 11 is located in the housing. Between the inner wall of housing 8 and electrode assembly 10, current collector 11 includes a first connecting portion 111, a second connecting portion 112 and a fuse portion 113. The first connecting portion 111 and the second connecting portion 112 are arranged at intervals. The fuse portion 113 is connected between the first connecting portion 111 and the second connecting portion 112. The first connecting portion 111 is connected to the second tab 103. The second connecting portion 112 is connected to the inner wall of housing 8. The fuse portion 113 is configured to cut off the connection between the first connecting portion 111 and the second connecting portion 112.

[0100] The outer casing 8, as a component in the battery cell 7 that forms the cavity 85, can have various shapes and sizes, such as cuboid or hexagonal prism. Specifically, the shape of the outer casing 8 can be determined according to the specific shape and size of the electrode assembly 10.

[0101] The outer casing 8 can be made of various materials, such as copper, iron, aluminum, stainless steel, or aluminum alloy, to ensure that the outer casing 8 has sufficient strength and service life to protect the components in the battery cell 7. The wall portion 81 can be a partial wall structure within the outer casing 8, on which components such as electrode terminals 9 of the battery cell 7 can be mounted.

[0102] Electrode assembly 10 is a component in the battery cell 7 where electrochemical reactions occur. The housing 8 may contain one or more electrode assemblies 10.

[0103] The electrode assembly 10 may include a positive electrode and a negative electrode with opposite polarities, which can serve as the positive and negative electrodes, respectively. Exemplarily, the electrode assembly 10 may also include a spacer, which is stacked between the positive and negative electrode to isolate them. The positive electrode, negative electrode, and spacer may be stacked and wound along the winding direction, or they may be stacked sequentially along their own thickness direction, with the spacer maintaining the isolation between the positive and negative electrode.

[0104] The electrode body 101 can be a structure composed of the main structure of the electrode plates in the electrode assembly 10. The first tab 102 and the second tab 103 can be two structures with opposite polarities, which extend from the electrode body 101. The first tab 102 and the second tab 103 are used to smoothly lead out the current of the electrode assembly 10.

[0105] The first tab 102 is electrically connected to the electrode terminal 9, which can mean that the first tab 102 is connected to the electrode terminal 9 via an adapter. By electrically connecting the second tab 103 to the inner wall of the outer casing 8, the electrode terminal 9 of the battery cell 7 and the outer casing 8 have opposite polarities. This allows the outer casing 8 to serve as a terminal for connecting to external electrical devices or charging devices, eliminating the need for the battery cell 7 to have two electrode terminals 9 with opposite polarities. This helps to reduce the size of the battery cell 7 and simplify its structure.

[0106] For example, the first tab 102 and the second tab 103 can extend from opposite sides of the electrode body 101, from the same side of the electrode body 101, or from adjacent sides of the electrode body 101.

[0107] The current collector 11 can be a device used to ensure a good connection between the second tab 103 and the inner wall of the housing 8. The first tab 102 and the second tab 103 have a multi-layer structure, consisting of multiple thin sheets extending from the main structure of the electrode. Connecting the second tab 103 to the current collector 11, and then connecting the current collector 11 to the inner wall of the housing 8, helps to improve the connection effect between the second tab 103 and the housing 8.

[0108] The first connecting portion 111, the second connecting portion 112, and the fuse portion 113 can be different structural parts of the current collector 11. The first connecting portion 111 and the second connecting portion 112 are two spaced-apart portions, and the fuse portion 113 connects between the first connecting portion 111 and the second connecting portion 112, allowing the electrical connection between the first connecting portion 111 and the second connecting portion 112 to be controlled by the fuse portion 113. For example, the first connecting portion 111 and the second connecting portion 112 can be two spaced-apart ring structures, or they can be sheet-like structures spaced apart along a predetermined direction. Those skilled in the art can configure the first connecting portion 111, the second connecting portion 112, and the fuse portion 113 connecting between the first connecting portion 111 and the second connecting portion 112 according to actual conditions, so that the current collector can effectively connect the second electrode 103 to the outer casing 8.

[0109] The first connecting part 111 may be the part of the current collector 11 used to connect with the second electrode 103, and the second connecting part 112 may be the part of the current collector 11 used to connect with the inner wall of the housing 8. For example, the first connecting part 111 may be connected to the second electrode 103 by welding, bonding or other means, and the second connecting part 112 may be connected to the inner wall of the housing 8 by welding, bonding or other means.

[0110] The fuse 113 can be a part used to connect or disconnect the electrical connection between the first connecting part 111 and the second connecting part 112. The fuse 113 connected between the first connecting part 111 and the second connecting part 112 is configured to disconnect the connection between the first connecting part 111 and the second connecting part 112. Specifically, the fuse 113 connected between the first connecting part 111 and the second connecting part 112 can disconnect the connection between the first connecting part 111 and the second connecting part 112 when the temperature exceeds a first threshold, so that the fuse 113 can disconnect the electrical connection between the first connecting part 111 and the second connecting part 112 when the temperature exceeds the first threshold.

[0111] For example, the first threshold may be the melting point of the fuse 113, so that the fuse 113 can be disconnected when the temperature exceeds the first threshold.

[0112] When the electrode terminal 9 is electrically connected to the outer casing 8, a short circuit occurs inside the battery cell 7. The first tab 102 and the second tab 103 of the battery cell 7 are short-circuited, the current flowing through the fuse 113 increases sharply, the fuse 113 experiences overcurrent, the heat generated by the fuse 113 increases, and the fuse 113 will melt because the temperature exceeds the first threshold, cutting off the electrical connection between the first connection 111 and the second connection 112, and breaking the short circuit loop between the first tab 102 and the second tab 103.

[0113] In the above structure, since the fuse 113 connected between the first connecting part 111 and the second connecting part 112 is configured to cut off the connection between the first connecting part 111 and the second connecting part 112, causing a short circuit inside the battery cell 7, when the fuse 113 experiences overcurrent, the fuse 113 will cut off the connection between the first connecting part 111 and the second connecting part 112 due to the temperature exceeding the first threshold, cutting off the circuit of the short circuit inside the battery cell 7, reducing the possibility of the battery cell 7 catching fire or exploding, making the battery cell 7 have higher reliability, which is beneficial to improving the reliability of the battery device 2.

[0114] For example, the first tab 102 can be a negative tab, the second tab 103 can be a positive tab, and the outer casing 8 can be made of aluminum.

[0115] In some embodiments, referring to FIG4 and FIG5, the fusible portion 113 is provided with a throttling orifice 1131, the throttling orifice 1131 penetrates the fusible portion 113 along the thickness direction of the fusible portion 113 to form a fusible structure 1132, the fusible structure 1132 is connected between the first connecting portion 111 and the second connecting portion 112 and is configured to cut off the connection between the first connecting portion 111 and the second connecting portion 112.

[0116] The throttling orifice 1131 can be a structure used to reduce the current flow area of ​​the current flowing through the fuse portion 113. The throttling orifice 1131 penetrates the fuse portion 113 along its thickness direction, forming a fuse structure 1132 with a smaller current flow area on the fuse portion 113. This allows the current flowing through the fuse structure 1132 to generate more heat, so that when an overcurrent occurs in the fuse portion 113, the temperature of the fuse structure 1132 can rise rapidly, thereby achieving fuse breaking.

[0117] By connecting the fusible structure 1132 between the first connecting part 111 and the second connecting part 112, when the fusible part 113 experiences an overcurrent, the temperature of the fusible structure 1132 can quickly exceed the first threshold to melt and sever the connection between the first connecting part 111 and the second connecting part 112.

[0118] In some embodiments, at least two throttling orifices 1131 are provided, and the at least two throttling orifices 1131 are spaced apart on the fuse portion 113, and the fuse structure 1132 is formed between two adjacent throttling orifices 1131.

[0119] By providing at least two throttling orifices 1131 on the fuse portion 113, the current flow area on the fuse portion 113 can be better reduced. By providing at least two throttling orifices 1131 at equal intervals on the fuse portion 113, one or at least two fuse structures 1132 can be provided between the first connecting portion 111 and the second connecting portion 112 at equal intervals, so that the current can flow through the fuse portion 113 more uniformly.

[0120] For example, when the first connecting portion 111 and the second connecting portion 112 are two annular structures spaced apart, at least two throttling orifices 1131 can form at least two fusion structures 1132 between the first connecting portion 111 and the second connecting portion 112; when the first connecting portion 111 and the second connecting portion 112 are sheet-like structures spaced apart along a preset direction, at least two throttling orifices 1131 can form at least three fusion structures 1132 between the first connecting portion 111 and the second connecting portion 112.

[0121] In some embodiments, referring to FIG6 and FIG7, the current collector 11 includes a first insulating structure 114, the first insulating structure 114 covering the fusible structure 1132, and the melting point of the first insulating structure 114 is lower than the melting point of the fusible structure 1132.

[0122] The first insulating structure 114 can be used to block the fused structure 1132 after it has been disconnected, preventing it from being reconnected to a certain extent. By covering the outer periphery of the fused structure 1132 with the first insulating structure 114 and making the melting point of the first insulating structure 114 lower than that of the fused structure 1132, when the fused structure 1132 melts, the first insulating structure 114 can melt and fill the disconnected part of the fused structure 1132. This allows the melted material of the first insulating structure 114 to continuously disconnect the electrical connection between the first connection part 111 and the second connection part 112, effectively reducing the possibility of the first connection part 111 and the second connection part 112 reconnecting, and improving the reliability of the battery cell 7.

[0123] In some embodiments, the first insulating structure 114 fills the throttling orifice 1131.

[0124] By filling the throttling orifice 1131 with the first insulating structure 114, the amount of the first insulating structure 114 provided on the fuse portion 113 can be increased, so that the first insulating structure 114 has a sufficient amount to fill the disconnection portion of the fuse structure 1132, thereby improving the effect of the first insulating structure 114 in reducing the possibility of the first connection portion 111 and the second connection portion 112 being electrically connected again.

[0125] In some embodiments, the surface of the first connection portion 111 facing the electrode assembly 10 is closer to the electrode assembly 10 than the surface of the fuse portion 113 facing the electrode assembly 10.

[0126] By setting the surface of the first connecting portion 111 facing the electrode assembly 10 to be closer to the electrode assembly 10 than the surface of the fuse portion 113 facing the electrode assembly 10, the surface of the first connecting portion 111 facing the electrode assembly 10 can be closer to the second tab 103, making it easier for the second tab 103 to be connected to the first connecting portion 111.

[0127] In some embodiments, along the thickness direction of the first connecting portion 111, the distance by which the first connecting portion 111 protrudes from the surface of the electrode assembly 10 toward the surface of the fuse portion 113 toward the electrode assembly 10 is L1, where 0.4mm≤L1≤1.2mm.

[0128] By setting the range of the distance L1 from the surface of the first connecting part 111 facing the electrode assembly 10 to the surface of the fuse part 113 facing the electrode assembly 10 in the thickness direction of the first connecting part 111 to 0.4mm≤L1≤1.2mm, not only can the surface of the first connecting part 111 facing the electrode assembly 10 be brought closer to the second tab 103, facilitating the connection between the first connecting part 111 and the second tab 103, but also the surface of the first connecting part 111 facing the electrode assembly 10 will not protrude too much from the surface of the fuse part 113 facing the electrode assembly 10, reducing the space occupied by the current collector 11 between the inner wall of the housing 8 and the electrode assembly 10.

[0129] The range of L1 for the distance L1 from the surface of the first connecting portion 111 facing the electrode assembly 10 in the thickness direction of the first connecting portion 111 to the surface of the fuse portion 113 facing the electrode assembly 10 can be set to 0.5mm≤L1≤1mm. For example, the distance L1 from the surface of the first connecting portion 111 facing the electrode assembly 10 in the thickness direction of the first connecting portion 111 to the surface of the fuse portion 113 facing the electrode assembly 10 can be 0.5mm, 0.8mm, or 1mm. This not only allows the surface of the first connecting portion 111 facing the electrode assembly 10 to better approach the second tab 103, facilitating the connection between the first connecting portion 111 and the second tab 103, but also prevents the surface of the first connecting portion 111 facing the electrode assembly 10 from protruding excessively from the surface of the fuse portion 113 facing the electrode assembly 10, reducing the space occupied by the current collector 11 between the inner wall of the housing 8 and the electrode assembly 10.

[0130] In some embodiments, the current collector 11 includes a first insulating structure 114, which covers the fuse portion 113, and the surface of the first insulating structure 114 facing the electrode assembly 10 is flush with the surface of the first connection portion 111 facing the electrode assembly 10.

[0131] By making the surface of the first insulating structure 114 covering the fusible portion 113 facing the electrode assembly 10 flush with the surface of the first connecting portion 111 facing the electrode assembly 10, the first insulating structure 114 can act on the electrode assembly 10 together with the first connecting portion 111, thereby increasing the surface area of ​​the current collector 11 facing the electrode assembly 10, which is beneficial to improving the convenience and stability of the current collector 11 during installation.

[0132] In some embodiments, the surface of the second connection portion 112 facing the inner wall of the housing 8 is closer to the inner wall of the housing 8 than the surface of the fuse portion 113 facing the inner wall of the housing 8.

[0133] By setting the surface of the second connecting part 112 facing the inner wall of the outer casing 8 to be closer to the inner wall of the outer casing 8 than the surface of the fused part 113 facing the inner wall of the outer casing 8, the surface of the second connecting part 112 facing the inner wall of the outer casing 8 can be closer to the inner wall of the outer casing 8, making it easier to connect the inner wall of the outer casing 8 to the second connecting part 112.

[0134] In some embodiments, along the thickness direction of the second connecting portion 112, the distance by which the surface of the second connecting portion 112 protrudes from the surface of the fused portion 113 toward the inner wall of the outer casing 8 is L2, where 0.4mm≤L2≤1.2mm.

[0135] By setting the range of the distance L2 from the surface of the second connecting part 112 facing the inner wall of the outer casing 8 to the surface of the fuse part 113 facing the inner wall of the outer casing 8 in the thickness direction of the second connecting part 112 to 0.4mm≤L2≤1.2mm, not only can the surface of the second connecting part 112 facing the inner wall of the outer casing 8 be closer to the inner wall of the outer casing 8, facilitating the connection between the second connecting part 112 and the inner wall of the outer casing 8, but also the surface of the second connecting part 112 facing the inner wall of the outer casing 8 will not protrude too much from the surface of the inner wall of the outer casing 8, reducing the space occupied by the current collector 11 between the inner wall of the outer casing 8 and the electrode assembly 10.

[0136] The distance L2 from the surface of the second connecting portion 112 facing the inner wall of the outer casing 8 to the surface of the fusible portion 113 facing the inner wall of the outer casing 8 in the thickness direction of the second connecting portion 112 is set to 0.5mm ≤ L2 ≤ 1mm. For example, the distance from the surface of the second connecting portion 112 facing the inner wall of the outer casing 8 to the surface of the fusible portion 113 facing the inner wall of the outer casing 8 in the thickness direction of the second connecting portion 112 can be 0.5mm, 0.8mm, or 1mm. This not only allows the surface of the second connecting portion 112 facing the inner wall of the outer casing 8 to be closer to the inner wall of the outer casing 8, facilitating the connection between the second connecting portion 112 and the inner wall of the outer casing 8, but also prevents the surface of the second connecting portion 112 facing the inner wall of the outer casing 8 from protruding excessively from the surface of the inner wall of the outer casing 8, reducing the space occupied by the current collector 11 between the inner wall of the outer casing 8 and the electrode assembly 10.

[0137] In some embodiments, the current collector 11 includes a first insulating structure 114, which covers the fuse portion 113, and the surface of the first insulating structure 114 facing the inner wall of the housing 8 is flush with the surface of the second connecting portion 112 facing the inner wall of the housing 8.

[0138] By aligning the surface of the first insulating structure 114 covering the fuselage portion 113 facing the inner wall of the housing 8 with the surface of the second connecting portion 112 facing the inner wall of the housing 8, the first insulating structure 114 can act together with the second connecting portion 112 on the inner wall of the housing 8, thereby increasing the surface area of ​​the current collector 11 facing the inner wall of the housing 8, which is beneficial to improving the convenience and stability of the current collector 11 during installation.

[0139] In some embodiments, the current collector 11 includes a second insulating structure 115, which is disposed on the surface of the first connection portion 111 away from the electrode assembly 10 and flush with the surface of the first insulating structure 114 facing the inner wall of the housing 8.

[0140] The second insulating structure 115 can be a structure used to support the first connecting portion 111. By making the first connecting portion 111 away from the surface of the electrode assembly 10, and making the second insulating structure 115 flush with the surface of the first insulating structure 114 facing the inner wall of the housing 8, the surfaces of the second insulating structure 115 facing the inner wall of the housing 8, the surfaces of the first insulating structure 114 facing the inner wall of the housing 8, and the surface of the first connecting portion 111 away from the electrode assembly 10 are all flush. This further increases the surface area of ​​the current collector 11 facing the inner wall of the housing 8, which is beneficial to improving the convenience and stability of the current collector 11 during installation.

[0141] In some embodiments, the second insulating structure 115 and the first insulating structure 114 are integrally formed.

[0142] The second insulating structure 115 and the first insulating structure 114 are integrally molded, meaning that the second insulating structure 115 and the first insulating structure 114 are integrally molded and manufactured simultaneously using an injection molding process. By using the current collector 11 as an insert to form the second insulating structure 115 and the first insulating structure 114, not only is the molding of the second insulating structure 115 and the first insulating structure 114 convenient, but it also helps to improve the overall structural strength of the current collector 11.

[0143] In some embodiments, the second insulating structure 115 is provided with a notch 1151, which penetrates the second insulating structure 115 along the thickness direction of the first connecting portion 111, and the second electrode 103 is welded to the area of ​​the first connecting portion 111 corresponding to the notch 1151 in the thickness direction of the first connecting portion 111.

[0144] The notch 1151 may refer to a portion of the second insulating structure 115 where no material is provided. It penetrates the second insulating structure 115 along the thickness direction of the first connecting portion 111, so that a portion of the first connecting portion 111 facing away from the surface of the electrode assembly 10 is exposed without the second insulating structure 115. This allows the welding equipment to perform welding from the notch 1151, so that the second tab 103 can be welded to the area of ​​the first connecting portion 111 corresponding to the notch 1151 in the thickness direction of the first connecting portion 111.

[0145] In some embodiments, the second connecting portion 112 is provided with a first through hole 1121 extending along its own thickness direction, the outer casing 8 is provided with a liquid injection hole 8321 that connects the interior of the outer casing 8 to the outside, the liquid injection hole 8321 is connected to the first through hole 1121, and the battery cell 7 also includes a cover 12, which is connected to the outer casing 8 and covers the liquid injection hole 8321.

[0146] The first through hole 1121 can be a hole-like structure provided on the second connecting portion 112, which penetrates the second connecting portion 112 along its thickness direction. The injection hole 8321 can be a hole-like structure for injecting electrolyte into the outer casing 8, which can penetrate along the thickness direction of the outer casing 8 to connect the interior of the outer casing 8 with the outside. By connecting the injection hole 8321 with the first through hole 1121, the electrolyte injection device can inject electrolyte into the outer casing 8 from the outside through the injection hole 8321 and the first through hole 1121.

[0147] The cap 12 can be a component used to seal the injection port 8321. By sealing the cap 12 to the housing 8 and covering the injection port 8321, a closed space is formed inside the housing 8. Exemplarily, the cap 12 can be welded to the housing 8, so that the cap 12 has a good sealing effect on the injection port 8321.

[0148] In some embodiments, the cover 12 is provided with a pressure relief structure 121.

[0149] By providing a pressure relief structure 121 on the cover 12, when the pressure inside the casing 8 becomes too high, the pressure relief structure 121 can open to expose the liquid injection hole 8321. The liquid injection hole 8321 can connect the inside of the casing 8 with the outside, allowing the pressure inside the casing 8 to be released to the outside. By integrating the pressure relief structure 121 on the cover 12, the number of components in the battery cell 7 can be reduced, which helps to simplify the structure of the battery cell 7.

[0150] For example, the pressure relief structure 121 may include a grooved structure.

[0151] In some embodiments, the outer casing 8 includes a cover 82 and a housing 83. The housing 83 forms a cavity 85 with an opening 84. The housing 83 includes an integrally formed sidewall 831 and a bottom wall 832. The bottom wall 832 is disposed opposite to the opening 84. The cover 82 covers the opening 84. The wall portion 81 is the cover 82. An injection hole 8321 is disposed on the bottom wall 832. The second connecting portion 112 is connected to the bottom wall 832.

[0152] The sidewalls 831 and bottom wall 832 can be manufactured using a one-piece forming process such as stamping, which helps to reduce the processing difficulty and cost of the cover 82. The cavity 85 formed by the shell 83 forms a sealed space to accommodate the electrolyte and other components in the battery cell 7 after the cover 82 closes to the opening 84.

[0153] By including a wall portion 81 and a bottom wall 832 opposite to the opening 84, and setting the liquid injection hole 8321 on the bottom wall 832, and connecting the second connecting portion 112 to the bottom wall 832, the electrode terminal 9 and the pressure relief structure 121 are respectively set at opposite ends of the battery cell 7, so that the battery cell 7 is less likely to affect the electrode terminal 9 when it is depressurized.

[0154] In some embodiments, the first connecting portion 111, the second connecting portion 112, and the fusion portion 113 are integrally formed structures.

[0155] The first connecting part 111, the second connecting part 112, and the fuse part 113 can be manufactured by integral forming processing methods such as casting and stamping, so that the current collector 11 can be manufactured as a whole and synchronously. This not only makes the processing and manufacturing of the current collector 11 convenient, but also gives the overall structure of the current collector 11 good strength. The first connecting part 111, the second connecting part 112, and the fuse part 113 can be manufactured by machining methods such as milling, by processing a whole blank, so that the bracket has low processing difficulty and low processing cost.

[0156] In some embodiments, the electrode assembly 10 is configured as a cylindrical wound structure, and the first connecting portion 111 and the second connecting portion 112 are configured as concentric annular structures, with the first connecting portion 111 located outside the second connecting portion 112.

[0157] By configuring the electrode assembly 10 as a cylindrical wound structure, the battery cell 7 is made into a cylindrical battery cell 7. By configuring the first connecting portion 111 and the second connecting portion 112 as a concentric ring structure, the current collector 11 is made into a disc-shaped current collector 11 that can be adapted to the cylindrical battery cell 7. By placing the first connecting portion 111, which connects to the second tab 103, outside the second connecting portion 112, the connection between the second tab 103 and the first connecting portion 111 is convenient.

[0158] Some embodiments of this application also provide a battery device 2, which includes the battery cell 7 provided by the above-described technical solution.

[0159] Some embodiments of this application also provide an electrical device, which includes the battery device 2 provided by the above-described technical solution, and the battery device 2 is used to provide electrical energy.

[0160] Some embodiments of this application provide a battery cell 7, which includes a housing 8, electrode terminals 9, an electrode assembly 10, and a current collector 11. The electrode assembly 10 is configured as a cylindrical wound structure. The housing 8 includes a cover 82 and a shell 83. The shell 83 forms a cavity 85 with an opening 84. The shell 83 includes an integrally formed sidewall 831 and a bottom wall 832. The bottom wall 832 is disposed opposite to the opening 84. The cover 82 covers the opening 84 and includes a wall portion 81. The electrode terminals 9 are disposed on the wall portion 81. The electrode assembly 10... The current collector is located in the cavity 85. The first connecting part 111 and the second connecting part 112 in the current collector 11 are configured as a concentric ring structure. The first connecting part 111 is located outside the second connecting part 112. The fuse part 113 is connected between the first connecting part 111 and the second connecting part 112. The first connecting part 111 is connected to the second electrode 103, and the second connecting part 112 is connected to the bottom wall 832. The fuse part 113 is configured to cut off the connection between the first connecting part 111 and the second connecting part 112 when the temperature exceeds a first threshold.

[0161] In the above structure, since the fuse 113 connected between the first connecting part 111 and the second connecting part 112 is configured to cut off the connection between the first connecting part 111 and the second connecting part 112 when the temperature exceeds the first threshold, a short circuit occurs inside the battery cell 7. When the fuse 113 experiences overcurrent, the fuse 113 will cut off the connection between the first connecting part 111 and the second connecting part 112 due to the temperature exceeding the first threshold, cutting off the circuit where the short circuit occurs inside the battery cell 7, reducing the possibility of the battery cell 7 catching fire or exploding, making the battery cell 7 more reliable, which is beneficial to improving the reliability of the battery device 2.

[0162] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A single battery cell, comprising: The outer casing, including the walls; Electrode terminals are disposed on the wall portion; An electrode assembly is housed in the housing. The electrode assembly includes an electrode body and a first electrode tab and a second electrode tab with opposite polarities extending from the electrode body. The first electrode tab is electrically connected to the electrode terminal. A current collector is located between the inner wall of the housing and the electrode assembly. The current collector includes a first connecting portion, a second connecting portion, and a fusible portion. The first connecting portion and the second connecting portion are arranged at intervals. The fusible portion is connected between the first connecting portion and the second connecting portion. The first connecting portion is connected to the second tab. The second connecting portion is connected to the inner wall of the housing. The fusible portion is configured to cut off the connection between the first connecting portion and the second connecting portion.

2. The battery cell according to claim 1, wherein, The fusible portion is provided with a throttling orifice, which penetrates the fusible portion along the thickness direction to form a fusible structure. The fusible structure is connected between the first connecting portion and the second connecting portion and is configured to cut off the connection between the first connecting portion and the second connecting portion.

3. The battery cell according to claim 2, wherein, The throttling orifice is provided with at least two, and the at least two throttling orifices are spaced apart on the fuse portion, and the fuse structure is formed between two adjacent throttling orifices.

4. The battery cell according to claim 2 or 3, wherein, The current collector includes a first insulating structure that covers the fusible structure, and the melting point of the first insulating structure is lower than the melting point of the fusible structure.

5. The battery cell according to claim 4, wherein, The first insulating structure fills the throttling orifice.

6. The battery cell according to any one of claims 1-5, wherein, The surface of the first connecting portion facing the electrode assembly is closer to the electrode assembly than the surface of the fused portion facing the electrode assembly.

7. The battery cell according to claim 6, wherein, Along the thickness direction of the first connecting portion, the distance by which the first connecting portion protrudes from the surface of the electrode assembly toward the surface of the fused portion toward the electrode assembly is L1, where 0.4mm≤L1≤1.2mm.

8. The battery cell according to claim 6 or 7, wherein, The current collector includes a first insulating structure that covers the fusible portion, and the surface of the first insulating structure facing the electrode assembly is flush with the surface of the first connecting portion facing the electrode assembly.

9. The battery cell according to any one of claims 1-8, wherein, The surface of the second connecting portion facing the inner wall of the housing is closer to the inner wall of the housing than the surface of the fused portion facing the inner wall of the housing.

10. The battery cell according to claim 9, wherein, Along the thickness direction of the second connecting part, the distance by which the surface of the second connecting part facing the inner wall of the outer shell protrudes from the surface of the fused part facing the inner wall of the outer shell is L2, where 0.4mm≤L2≤1.2mm.

11. The battery cell according to claim 9 or 10, wherein, The current collector includes a first insulating structure that covers the fusible portion, and the surface of the first insulating structure facing the inner wall of the housing is flush with the surface of the second connecting portion facing the inner wall of the housing.

12. The battery cell according to claim 11, wherein, The current collector includes a second insulating structure, which is disposed on the surface of the first connection portion away from the electrode assembly and flush with the surface of the first insulating structure facing the inner wall of the housing.

13. The battery cell according to claim 12, wherein, The second insulation structure and the first insulation structure are integrally formed.

14. The battery cell according to claim 12 or 13, wherein, The second insulating structure has a notch that penetrates the second insulating structure along the thickness direction of the first connecting part, and the second electrode is welded to the area of ​​the first connecting part corresponding to the notch in the thickness direction of the first connecting part.

15. The battery cell according to any one of claims 1-14, wherein, The second connecting part is provided with a first through hole extending along the thickness direction. The outer shell is provided with a liquid injection hole that connects the interior of the outer shell to the outside. The liquid injection hole is connected to the first through hole. The battery cell also includes a sealing cover, which is connected to the outer shell and covers the liquid injection hole.

16. The battery cell according to claim 15, wherein, The cover is equipped with a pressure relief structure.

17. The battery cell according to claim 15 or 16, wherein, The outer casing includes a cover and a housing. The housing forms a cavity with an opening. The housing includes an integrally formed side wall and a bottom wall. The bottom wall is disposed opposite to the opening. The cover covers the opening. The cover includes the wall portion. The liquid injection hole is disposed on the bottom wall. The second connecting portion is connected to the bottom wall.

18. The battery cell according to any one of claims 1-17, wherein, The first connecting part, the second connecting part, and the fusion part are integrally formed.

19. The battery cell according to any one of claims 1-18, wherein, The electrode assembly is configured as a cylindrical wound structure, and the first connecting part and the second connecting part are configured as a concentric ring structure, with the first connecting part located outside the second connecting part.

20. The battery cell according to any one of claims 1-19, wherein, The first electrode is the negative electrode, and the second electrode is the positive electrode.

21. A battery device comprising a battery cell as described in any one of claims 1 to 20.

22. An electrical device comprising the battery device as claimed in claim 21, the battery device being used to provide electrical energy.

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