Battery cell, battery device, and electric device

Abstract

The application discloses a battery monomer, a battery device and an electric equipment. The battery monomer comprises an end cover assembly, the end cover assembly comprises an end cover, a pole terminal and an insulation assembly. The end cover is provided with a mounting hole, the pole terminal comprises a terminal body and an annular extension part protruding from the outer circumferential surface of the terminal body. The extension part is connected to the outer circumferential surface of the end of the terminal body and forms a continuous transition surface with the end surface of the terminal body, and at least part of the terminal body is accommodated in the mounting hole. The insulation assembly is arranged around the pole terminal, the insulation assembly comprises a first insulation part arranged between the end cover and the terminal body and a second insulation part arranged between the extension part and the end cover, and the extension part abuts against the side surface of the second insulation part away from the end cover. The technical scheme of the embodiment of the application can improve the connection stability of the battery monomer and the busbar assembly and improve the operation stability of the battery device.

Description

Technical Field

[0001] This application relates to the field of batteries, and in particular to a battery cell, a battery device, and an electrical appliance. Background Technology

[0002] With the development of new energy technologies, batteries are being used more and more widely, such as in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, and power tools.

[0003] The development of battery technology must take into account multiple design factors. Improving the stability of individual battery cells and assembly efficiency is also one of the research issues in this field. Utility Model Content

[0004] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device that can improve the connection stability between the battery cell and the busbar assembly, thereby improving the operational stability of the battery device.

[0005] In a first aspect, this application provides a battery cell including an end cap assembly. The end cap assembly includes an end cap, a terminal post, and an insulating assembly. The end cap has a mounting hole. The terminal post includes a terminal body and an annular extension protruding from the outer peripheral surface of the terminal body. The extension is connected to the outer peripheral surface of the end of the terminal body and forms a continuous transition surface with the end face of the terminal body. At least a portion of the terminal body is accommodated in the mounting hole. The insulating assembly surrounds the terminal post and includes a first insulating member disposed between the end cap and the terminal body, and a second insulating member disposed between the extension and the end cap. The extension and the second insulating member abut against the surface of the side facing away from the end cap.

[0006] In the technical solution of this application embodiment, mounting holes are provided on the end cap for mounting the terminal post, improving the accuracy and efficiency of the terminal post mounting position. The terminal body is used to connect the electrode assembly and transmit the electrical energy of the electrode assembly to the outside. The extension increases the area of ​​the terminal post end face, which can increase the welding connection area when welding with the busbar. During the operation of the battery cell, the current-carrying area of ​​the terminal body can be increased, thereby reducing the resistance of the terminal post, reducing the heat generated when current passes through, and reducing thermal runaway caused by local overheating. Furthermore, the increased current-carrying area allows for a larger current to pass through, meeting the needs of high-power applications, improving fast charging performance, and meeting high-rate discharge requirements. Higher current capacity can accelerate the charging speed, shorten the discharge time, and increase the power density of the battery. The first insulating member can be used for insulation between the end cap and the terminal post, and the second insulating member is used for insulation between the extension and the end cap, improving the insulation safety performance of the battery cell.

[0007] In some embodiments, a recess is provided on the surface of the terminal body facing the first insulating member, and the first insulating member is correspondingly embedded in the recess. In the above structure, by providing the recess, the area where the first insulating member is provided is increased, the creepage distance between the extension and the end cap is increased, the insulation safety performance is improved, thereby improving the stability of the battery cell during operation.

[0008] In some embodiments, the outer peripheral surface of the terminal body protrudes outward to form a protrusion. The protrusion and the extension are spaced apart along the axial direction of the terminal body, and a mounting groove is formed between the protrusion and the extension. The edge portion of the end cap is engaged in the mounting groove to limit the axial displacement of the terminal relative to the end cap. In the above structure, by providing the protrusion and the extension to cooperate in forming a mounting groove, a snap-fit ​​connection with the end cap is achieved, limiting the axial movement of the terminal body relative to the end cap and improving the stability of the overall structure.

[0009] In some embodiments, the circumferential width W of the extension should satisfy: 1mm ≤ W ≤ 4mm. The above technical solution, by setting a reasonable width for the extension, can increase the welding area of ​​the electrode terminal while reducing the space occupied by the extension, thereby improving the energy density of the battery cell.

[0010] In some embodiments, the battery cell further includes a housing with an opening, and an end cap including an end cap body, a bent portion, and a snap-fit ​​portion. The end cap body closes to the opening, and a mounting hole is provided through the end cap body. The bent portion is connected to the edge of the end cap body and bends away from the housing, forming an annular structure surrounding the protrusion. The snap-fit ​​portion extends from the end of the bent portion toward the terminal body and snaps into a mounting groove. In the above structure, the end cap body is sealed to the housing, forming the main part of the battery cell casing. The bent portion is arranged around the terminal body, improving the stability of the connection with the terminal post. The snap-fit ​​portion extends into the mounting groove, restricting the axial movement of the terminal body relative to the end cap, thus improving the overall structural stability.

[0011] In some embodiments, the first insulating member includes a first part, a second part, and a third part. The first part is disposed between the end cap body and the snap-fit ​​portion, the second part is disposed between the protrusion and the snap-fit ​​portion, and the third part is disposed between the protrusion and the bend portion. The first part, the second part, and the third part are sequentially connected to form an integrally formed structure. In the above structure, the first part is used to insulate the bend portion from external electrical components. The extension abuts against the surface of the fourth part, reducing the insulation between the end cap body and the snap-fit ​​portion. The second part is used for insulation between the protrusion and the snap-fit ​​portion, and the third part is used for insulation between the bend portion and external electrical components. The extension abuts against the surface of the fourth part, reducing the insulation between the protrusion and the bend portion. The three parts are integrally formed, creating a stable insulating structure and increasing the creepage distance between the terminal block and the end cap, thus improving insulation safety performance.

[0012] In some embodiments, the second insulating member includes a fourth portion and a fifth portion. The fourth portion is located on the side of the latching portion away from the housing, and the fifth portion is located on the side of the bent portion away from the terminal body. An extension abuts against the surface of the fourth portion away from the latching portion. In the above structure, the fourth portion serves to insulate the bent portion from external electrical components. The extension abutting against the surface of the fourth portion provides insulation between the latching portion and external electrical components, and the fifth portion also provides insulation between the bent portion and external electrical components. The extension abutting against the surface of the fourth portion reduces the risk of displacement of the second insulating member relative to the terminal post.

[0013] In some embodiments, the radial outer contour of the fourth portion exceeds the maximum radial outer contour of the extension. This structure increases the creepage distance between the extension and the end cap body, reducing the risk of a short circuit between the terminal block and the end cap.

[0014] In some embodiments, the terminal block, insulating components, and end cap are integrally molded using an insert injection molding process to form an integrated sealed structure. The above technical solution effectively improves the insulation and sealing performance between the end cap and the terminal block, while also increasing the assembly efficiency of the battery cell and the overall structural strength.

[0015] Secondly, this application provides a battery device including a busbar and the battery cells described in the above embodiments. The busbar connects two adjacent battery cells and has positioning holes. The positioning holes correspond to the extension and the insulating component, allowing the extension and the second insulating component to be exposed to the outside through the positioning holes. In the above structure, multiple battery cells are connected in series or parallel by providing the busbar. The positioning holes on the busbar allow observation of the welding gap between the terminal block and the busbar, improving the accuracy of the welding position and increasing welding efficiency.

[0016] In some embodiments, the central axis of the positioning hole is eccentrically positioned to the axis of the terminal post. This structure, by placing the positioning hole at the edge of the terminal post, increases the welding area between the busbars, improves the connection stability between the busbars and the battery cells, increases the current-carrying area, enhances fast-charging performance, and shortens discharge time, thereby effectively improving the performance of the battery device.

[0017] In some embodiments, for each pole terminal, there are two positioning holes, which are symmetrically arranged along the central axis of the pole terminal. This structure facilitates observation of the welded joint, further improving the accuracy of the weld.

[0018] In some embodiments, the battery device further includes a welded connection formed between the busbar and the terminal block, and the welded connection is located in the axial middle region of the terminal block. The above structure, by placing the welded connection in the central region of the terminal block, increases the welding area and improves the current carrying capacity.

[0019] Thirdly, this application provides an electrical device that includes the battery device described in the above embodiments, the battery device being used to provide electrical energy.

[0020] 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

[0021] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0022] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0023] Figure 2 Explosion-proof diagrams of battery devices provided in some embodiments of this application;

[0024] Figure 3 This is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0025] Figure 4 This is a partial structural schematic diagram of the end cap assembly of a battery cell provided in some embodiments of this application;

[0026] Figure 5 A partial structural schematic diagram of the end cap assembly of a battery cell provided in other embodiments of this application;

[0027] Figure 6 A partial structural schematic diagram of the end cap assembly of a battery cell provided in other embodiments of this application;

[0028] Figure 7 This is a partial structural schematic diagram of a battery device provided in some embodiments of this application;

[0029] Figure 8 This is a partial structural schematic diagram of a battery device provided in other embodiments of this application;

[0030] Figure 9 for Figure 8 A magnified structural diagram of part A in the middle.

[0031] Detailed Explanation of Reference Numerals

[0032] 1. Vehicle; 2. Battery unit; 3. Controller; 4. Motor; 5. Housing; 5a. First housing section; 5b. Second housing section; 5c. Reception space; 6. Battery cell; 10. Electrode assembly; 20. Housing; 30. End cap assembly; 301. End cap; 302. Terminal post; 303. Insulation assembly; 304. Terminal body; 305. Extension; 306. First insulating component; 307. Second insulating component; 308. Recess; 309. Protrusion; 310. End cap body; 311. Bending portion; 312. Snap-fit ​​portion; 313. First part; 314. Second part; 315. Third part; 316. Fourth part; 317. Fifth part; 318. Positioning hole; 40. Housing; 50. Electrode terminal; 7. Busbar. Detailed Implementation

[0033] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0035] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0036] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0037] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0038] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0039] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0040] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0041] 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.

[0042] 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.

[0043] 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°-95°, the two directions can be considered perpendicular; if the angle between two directions is 0°-5°, the two directions can be considered parallel.

[0044] In this application, "multiple" means two or more (including two).

[0045] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0046] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0047] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. 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, prevents short circuits while allowing active ions to pass through.

[0048] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0049] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0050] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0051] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0052] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0053] As an example, negative electrode active materials can be filled or / and deposited within the negative electrode current collector.

[0054] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0055] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0056] In some embodiments, the separator is a separator membrane. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0057] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0058] In some embodiments, the battery cell also 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.

[0059] Liquid electrolytes include electrolyte salts and solvents.

[0060] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0061] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0062] In some implementations, the electrode assembly is a stacked structure.

[0063] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0064] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0065] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0066] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0067] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0068] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0069] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0070] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. As an example, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0071] As an example, the 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. This application does not have any particular limitations.

[0072] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0073] In some embodiments, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the tab. The electrode terminal can be directly connected to the tab, or it can be indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the housing.

[0074] Two battery cells are typically interconnected to form a group, and multiple battery cells are interconnected to form a battery device. As the volume of the terminal block decreases, the welding area with the terminal block also decreases, resulting in a reduction in the current carrying capacity of the battery cell. This reduction in current carrying capacity, coupled with an increase in localized overheating, leads to a decrease in the operational stability of the battery cell.

[0075] In view of this, this application provides a battery cell with mounting holes on the end cap for mounting terminal posts, improving the accuracy and efficiency of terminal post mounting. The terminal body is used to connect to the electrode assembly, transmitting the electrical energy of the electrode assembly to the outside world. The extension increases the area of ​​the terminal post end face, increasing the welding connection area when welding with the busbar. During battery cell operation, the increased current-carrying area of ​​the terminal body reduces the resistance of the terminal post, reduces heat generated when current flows, and reduces thermal runaway caused by local overheating. Furthermore, the increased current-carrying area allows for greater current flow, meeting the needs of high-power applications, improving fast-charging performance, and meeting high-rate discharge requirements. Higher current capacity accelerates charging speed, shortens discharge time, and increases battery power density. A first insulating member is used for insulation between the end cap and the terminal post, and a second insulating member is used for insulation between the extension and the end cap, improving the insulation safety performance of the battery cell.

[0076] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0077] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0078] 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.

[0079] 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.

[0080] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be housed in the housing by fixing the battery module in the housing.

[0081] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0086] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. 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. This application does not impose any special limitations on the above-mentioned electrical devices.

[0087] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

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

[0089] like Figure 1 As shown, 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 This is a schematic diagram of a battery explosion provided for some embodiments of this application. For example... Figure 2 As shown, the battery device 2 includes a housing 5 and battery cells 6, with the battery cells 6 housed within the housing 5. The battery cell 6 can be the smallest unit that makes up a battery.

[0093] The housing 5 is used to house the battery cell 6, 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 6. 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 6. If there are multiple battery cells 6, they can be connected in series, in parallel, or in a mixed manner. A mixed connection means that multiple battery cells 6 are connected in both series and parallel.

[0097] Multiple battery cells 6 can be directly connected in series, parallel, or in a mixed manner, and then the whole composed of multiple battery cells 6 can be housed in the housing 5; of course, multiple battery cells 6 can also be connected in series, parallel, or in a mixed manner to form a battery module, and multiple battery modules can then be connected in series, parallel, or in a mixed manner to form a whole, and housed in the housing 5.

[0098] Please refer to the reference. Figures 3 to 5 , Figure 3 This is a schematic diagram of the structure of a battery cell provided in some embodiments of this application. Figure 4 This is a partial structural schematic diagram of the end cap assembly of a battery cell provided in some embodiments of this application. Figure 5 This is a partial structural schematic diagram of the end cap assembly of a battery cell provided in some other embodiments of this application.

[0099] As shown in the figure, the battery cell 6 provided in this embodiment includes an end cap assembly 30, which includes an end cap 301, a terminal post 302, and an insulating assembly 303. The end cap 301 has a mounting hole. The terminal post 302 includes a terminal body 304 and an annular extension 305 protruding from the outer peripheral surface of the terminal body 304. The extension 305 is connected to the outer peripheral surface of the end of the terminal body 304 and forms a continuous transition surface with the end face of the terminal body 304. At least a portion of the terminal body 304 is accommodated in the mounting hole. The insulating assembly 303 surrounds the terminal post 302 and includes a first insulating member 306 disposed between the end cap 301 and the terminal body 304, and a second insulating member 307 disposed between the extension 305 and the end cap 301. The extension 305 and the second insulating member 307 abut against the side surface of the second insulating member facing away from the end cap 301.

[0100] The mounting hole in the end cap 301 serves as the assembly channel for the pole terminal 302. Its dimensions match the outer diameter of the terminal body 304 to ensure assembly accuracy. The terminal body 304 is the core channel for current transmission, possessing high conductivity and corrosion resistance. Its surface can be nickel-plated to enhance oxidation resistance. The outer diameter of the extension 305 is larger than that of the terminal body 304, forming a stepped structure. This increases the contact area and improves connection reliability. The extension 305 connects to the outer peripheral surface of the end of the terminal body 304 and forms a continuous transition surface with the end face of the terminal body 304. This means that the cross-sectional area of ​​the end of the pole terminal 302 is larger than that of the middle portion.

[0101] In the technical solution of this application embodiment, the end cap 301 is provided with mounting holes for mounting the terminal post 302, which improves the accuracy and efficiency of the mounting position of the terminal post 302. The terminal body 304 is used to connect the electrode assembly 10 and transmit the electrical energy of the electrode assembly 10 to the outside. The extension 305 increases the area of ​​the end face of the terminal post 302, which can increase the welding connection area when welding with the busbar 7. During the operation of the battery cell 6, the current-carrying area of ​​the terminal body 304 can be increased, thereby reducing the resistance of the terminal post 302, reducing the heat when current passes through, and reducing thermal runaway caused by local overheating. Furthermore, the increased current-carrying area allows a larger current to pass through, meeting the needs of high-power applications, improving fast charging performance, and meeting the requirements of high-rate discharge. Higher current capacity can accelerate the charging speed, shorten the discharge time, and increase the power density of the battery. The first insulating member 306 can be used for insulation between the end cap 301 and the terminal 302, and the second insulating member 307 is used for insulation between the extension 305 and the end cap 301, thereby improving the insulation safety performance of the battery cell 6.

[0102] like Figure 5As shown, in some embodiments of this application, the surface of the terminal body 304 facing the first insulating member 306 is provided with a recess 308, and the first insulating member 306 is correspondingly embedded in the recess 308. In the above structure, by providing the recess 308, the area where the first insulating member 306 is provided is increased, the creepage distance between the extension 305 and the end cap 301 is increased, the insulation safety performance is improved, thereby improving the stability of the battery cell 6 during operation.

[0103] In some embodiments of this application, a protrusion 309 protrudes outward from the outer peripheral surface of the terminal body 304. The protrusion 309 and the extension 305 are spaced apart along the axial direction of the terminal body 304, and a mounting groove is formed between the protrusion 309 and the extension 305. The edge portion of the end cap 301 is engaged in the mounting groove to limit the axial displacement of the pole terminal 302 relative to the pole terminal 302. In the above structure, by providing the protrusion 309 and the extension 305 to cooperate in forming a mounting groove, the engagement with the end cap 301 is achieved, limiting the axial movement of the terminal body 304 relative to the end cap 301 and improving the stability of the overall structure.

[0104] like Figure 4 As shown, in some embodiments of this application, the circumferential width W of the extension 305 should satisfy: 1mm ≤ W ≤ 4mm. The above technical solution, by setting a reasonable width for the extension 305, can increase the welding area of ​​the electrode terminal 302 while reducing the space occupied by the extension 305, thereby improving the energy density of the battery cell 6.

[0105] like Figure 5 As shown, in some alternative embodiments, the orthographic projection of the extension 305 onto the second insulating member 307 is an annular shape, and the minimum width K of the annular shape should satisfy: K≥1mm.

[0106] In some embodiments of this application, the battery cell 6 further includes a housing 40 with an opening. An end cap 301 includes a main body, a bent portion 311, and a snap-fit ​​portion 312. The main body of the end cap 301 covers the opening, and a mounting hole is provided through the main body. The bent portion 311 is connected to the edge of the main body of the end cap 301 and bends away from the housing 40, forming an annular structure surrounding the protrusion 309. The snap-fit ​​portion 312 extends from the end of the bent portion 311 toward the terminal body 304 and snaps into the mounting groove. In the above structure, the main body of the end cap 301 is sealed to the housing 40, forming the main part of the outer casing 20 of the battery cell 6. The bent portion 311 surrounds the terminal body 304, improving the stability of the connection with the terminal post 302. The snap-fit ​​portion 312 extends into the mounting groove, restricting the axial movement of the terminal body 304 relative to the end cap 301, thus improving the overall structural stability.

[0107] like Figure 6As shown, in some embodiments of this application, the first insulating member 306 includes a first portion 313, a second portion 314, and a third portion 315. The first portion 313 is disposed between the end cap 301 body and the snap-fit ​​portion 312, the second portion 314 is disposed between the protrusion 309 and the snap-fit ​​portion 312, and the third portion 315 is disposed between the protrusion 309 and the bent portion 311. The first portion 313, the second portion 314, and the third portion 315 are sequentially connected to form an integrally formed structure. In the above structure, the first portion 313 is used to insulate the bent portion 311 from external electrical components. The extension portion 305 abuts against the surface of the fourth portion 316, reducing the insulation between the end cap 301 body and the snap-fit ​​portion 312. The second portion 314 is used for insulation between the protrusion 309 and the snap-fit ​​portion 312, and the third portion 315 is used for insulation between the bent portion 311 and external electrical components. The extension 305 abuts against the surface of the fourth part 316, reducing the insulation between the protrusion 309 and the bend 311. The three parts are integrally formed, creating a stable insulation structure and increasing the creepage distance between the pole terminal 302 and the end cap 301, thereby improving insulation safety performance.

[0108] In some embodiments of this application, the second insulating member 307 includes a fourth portion 316 and a fifth portion 317. The fourth portion 316 is located on the side of the latching portion 312 away from the housing 40, and the fifth portion 317 is located on the side of the bent portion 311 away from the terminal body 304. An extension portion 305 abuts against the surface of the fourth portion 316 away from the latching portion 312. In the above structure, the fourth portion 316 serves to insulate the bent portion 311 from external electrical components. The extension portion 305 abuts against the surface of the fourth portion 316, thus insulating the latching portion 312 from external electrical components. The fifth portion 317 also serves to insulate the bent portion 311 from external electrical components. The extension portion 305 abutting against the surface of the fourth portion 316 reduces the risk of displacement of the second insulating member 307 relative to the terminal 302.

[0109] In some embodiments of this application, the outer contour of the fourth portion 316 in the radial direction exceeds the maximum radial contour of the extension 305. This structure increases the creepage distance between the extension 305 and the end cap 301 body, reducing the risk of a short circuit between the terminal block 302 and the end cap 301.

[0110] In some embodiments of this application, the terminal block 302, the insulating component 303, and the end cap 301 are integrally formed by insert injection molding to create an integrated sealed structure. The above technical solution effectively improves the insulation and sealing performance between the end cap 301 and the terminal block 302, while also increasing the assembly efficiency of the battery cell 6 and the overall structural strength.

[0111] like Figures 7 to 9 As shown, an embodiment of this application provides a battery device 2, which includes a busbar 7 and a battery cell 6 as described in the above embodiment. The busbar 7 connects two adjacent battery cells 6, and a positioning hole 318 is provided on the busbar 7. The position of the positioning hole 318 corresponds to the extension 305 and the insulating component 303, so that the extension 305 and the second insulating component 307 can be exposed to the outside through the positioning hole 318.

[0112] When the terminal 302 is welded to the busbar 7, an observation hole is opened at the center of the terminal 302 corresponding to the busbar 7. The end face of the terminal 302 facing the busbar 7 is recessed to form a groove corresponding to the observation hole. The observation hole and the groove of the terminal can be used for positioning. Before welding, it is possible to check whether the busbar 7 is misaligned. After welding, the welding gap between the busbar 7 and the terminal can be detected through the observation hole. The opening in the busbar 7 also helps to release stress during the welding process. When the size of the terminal 302 is reduced, the weldable area between the terminal 302 and the busbar 7 is reduced, which is not conducive to the current carrying capacity of the entire battery pack. Moreover, due to the small remaining weldable area, the welding trajectory is closer to the observation hole, which makes it easy to weld into the hole, increasing the risk of welding through the terminal 302. If the diameter of the observation hole and the groove is reduced, there will be situations where the opening is too small to observe and it is impossible to determine whether there is welding misalignment or to detect the welding gap.

[0113] The battery device 2 provided in this application has mounting holes on the end cap 301 for mounting the terminal post 302, which improves the accuracy and efficiency of the mounting position of the terminal post 302. The terminal body 304 is used to connect the electrode assembly 10 and transmit the electrical energy of the electrode assembly 10 to the outside. The extension 305 increases the area of ​​the end face of the terminal post 302, which can increase the welding connection area when welding with the busbar 7. Furthermore, multiple battery cells 6 are connected in series or parallel by setting the busbar 7. The positioning hole 318 is set on the busbar 7, and the welding gap between the terminal post 302 and the busbar 7 can be observed through the positioning hole 318, which improves the accuracy of the welding position and improves the welding efficiency.

[0114] For example, the aperture R of the positioning hole 318 satisfies: 2mm ≤ R ≤ 3mm. If the aperture of the positioning hole 318 is too small, the welding position and weld seam cannot be observed; if the aperture of the positioning hole 318 is too large, the area of ​​the welded connection is reduced. Therefore, setting the aperture of the positioning hole 318 within the above range ensures convenient observation of the welding process while maintaining the current flow area between the pole terminal 302 and the busbar 7.

[0115] In some embodiments of this application, the central axis of the positioning hole 318 is eccentrically positioned to the axis of the terminal 302. This structure, by positioning the positioning hole 318 at the edge of the terminal 302, increases the welding area between the busbars 7, improves the connection stability between the busbars 7 and the battery cell 6, increases the current flow area, enhances fast charging performance, and shortens discharge time, thereby effectively improving the performance of the battery device 2.

[0116] In some embodiments of this application, for each pole terminal 302, there are two positioning holes 318, and the two positioning holes 318 are symmetrically arranged along the central axis of the pole terminal 302. The above structure facilitates the observation of the welded connection and further improves the accuracy of the welded part.

[0117] In some embodiments of this application, the battery device 2 further includes a welded connection portion formed between the busbar 7 and the terminal 302, and the welded connection portion is located in the axial middle region of the terminal 302.

[0118] The above structure places the welding connection in the central area of ​​the pole terminal 302, which can increase the welding area and improve the current carrying capacity.

[0119] For example, the radius of the welded joint is 3mm to 5mm.

[0120] For example, the minimum distance between the edge of the welded joint and the edge of the extension 305 is 2mm to 4mm. This distance reduces the risk of weld damage to the second insulating member 307 during the welding process.

[0121] In some alternative embodiments, the battery device 2 includes a busbar 7 and a battery cell 6. The battery cell 6 includes an end cap assembly 30, which includes an end cap 301, a terminal post 302, and an insulating assembly 303. The end cap 301 has a mounting hole. The terminal post 302 includes a terminal body 304 and an annular extension 305 protruding from the outer peripheral surface of the terminal body 304. The extension 305 is connected to the outer peripheral surface of the end of the terminal body 304 and forms a continuous transition surface with the end face of the terminal body 304. At least a portion of the terminal body 304 is accommodated in the mounting hole. The insulating assembly 303 surrounds the terminal post 302 and includes a first insulating member 306 disposed between the end cap 301 and the terminal body 304, and a second insulating member 307 disposed between the extension 305 and the end cap 301. The extension 305 and the second insulating member 307 abut against the side surface of the second insulating member facing away from the end cap 301. The maximum outer diameter of the extension 305 is larger than the diameter of the mounting hole. A recess 308 is provided on the surface of the terminal body 304 facing the first insulating member 306, and the first insulating member 306 is correspondingly embedded in the recess 308. A protrusion 309 protrudes outward from the outer peripheral surface of the terminal body 304, and the protrusion 309 and the extension 305 are spaced apart along the axial direction of the terminal body 304, forming a mounting groove between the protrusion 309 and the extension 305. The battery cell 6 also includes a housing 40, which has an opening. The end cap 301 includes an end cap 301 body, a bending portion 311, and a snap-fit ​​portion 312. The end cap 301 body covers the opening, and the mounting hole penetrates through the end cap 301 body. The bending portion 311 is connected to the edge of the end cap 301 body and bends and extends away from the housing 40, forming an annular structure surrounding the protrusion 309. The snap-fit ​​portion 312 extends from the end of the bending portion 311 toward the terminal body 304 and snaps into the mounting groove. The terminal block 302, the insulating component 303, and the end cap 301 are integrally formed by insert injection molding to create a sealed structure. The busbar 7 connects two adjacent battery cells 6 and has a positioning hole 318. The positioning hole 318 corresponds to the extension 305 and the insulating component 303, allowing the extension 305 and the second insulating component 307 to be exposed to the outside through the positioning hole 318.

[0122] An embodiment of this application also provides an electrical device that includes the battery device 2 described in the above embodiments, the battery device 2 being used to provide electrical energy. Since the electrical device includes the electrical device described in the above embodiments, it can also achieve the aforementioned technical effects, and will not be elaborated further here.

[0123] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, Includes an end cap assembly, the end cap assembly comprising: End cap, with mounting holes; A terminal post includes a terminal body and an annular extension protruding from the outer peripheral surface of the terminal body. The extension is connected to the outer peripheral surface of the end of the terminal body and forms a continuous transition surface with the end face of the terminal body. At least a portion of the terminal body is accommodated in the mounting hole. An insulating assembly is provided around the pole terminal. The insulating assembly includes a first insulating member disposed between the end cap and the terminal body, and a second insulating member disposed between the extension and the end cap. The extension abuts against the side surface of the second insulating member opposite to the end cap.

2. The battery cell according to claim 1, characterized in that, The terminal body has a recess on the surface facing the first insulating member, and the first insulating member is correspondingly embedded in the recess.

3. The battery cell according to claim 2, characterized in that, The outer peripheral surface of the terminal body protrudes outward to form a protrusion. The protrusion and the extension are spaced apart along the axial direction of the terminal body. A mounting groove is formed between the protrusion and the extension. The edge portion of the end cap is inserted into the mounting groove to limit the relative axial displacement of the pole terminal.

4. The battery cell according to claim 3, characterized in that, The circumferential width W of the extension should satisfy: 1mm≤W≤4mm.

5. The battery cell according to claim 3, characterized in that, The battery cell further includes a housing having an opening, and the end cap includes: An end cap body covers the opening, and the mounting hole is provided through the end cap body; The bent portion is connected to the edge of the end cap body and bends and extends away from the shell to form a ring structure surrounding the protrusion; The snap-fit ​​portion extends from the end of the bent portion toward the terminal body and snaps into the mounting groove.

6. The battery cell according to claim 5, characterized in that, The first insulating element includes: The first part is located between the end cap body and the snap-fit ​​portion; The second part is located between the protrusion and the snap-fit ​​portion; The third part is located between the protrusion and the bend. The first part, the second part, and the third part are connected in sequence to form an integral structure.

7. The battery cell according to claim 5, characterized in that, The second insulating element includes: The fourth part is located on the side of the snap-fit ​​portion opposite to the housing; The fifth part is located on the side of the bent portion away from the terminal body; The extension abuts against the side surface of the fourth part that is opposite to the snap-fit ​​portion.

8. The battery cell according to claim 7, characterized in that, The outer contour of the fourth part in the radial direction exceeds the maximum radial contour of the extension.

9. The battery cell according to any one of claims 1-8, characterized in that, The pole terminal, insulating component, and end cap are integrally formed by insert injection molding process to form an integral sealed structure.

10. A battery device, characterized in that, include: The battery cell as described in any one of claims 1-9; A busbar is connected between two adjacent battery cells. The busbar has a positioning hole, the position of which corresponds to the extension and the insulating component, so that the extension and the second insulating component can be exposed to the outside through the positioning hole.

11. The battery device according to claim 10, characterized in that, The central axis of the positioning hole is eccentrically set with respect to the axis of the pole terminal.

12. The battery device according to claim 11, characterized in that, For each of the pole terminals, there are two positioning holes, and the two positioning holes are symmetrically arranged along the central axis of the pole terminal.

13. The battery device according to claim 10, characterized in that, The battery device further includes a welded connection portion formed between the busbar and the terminal block, and the welded connection portion is located in the axial middle region of the terminal block.

14. An electrical appliance, characterized in that, The electrical equipment includes a battery device as described in any one of claims 10-13, the battery device being used to provide electrical energy.

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