Pole assembly and battery cell

Abstract

The utility model discloses a pole assembly and a battery monomer, and relates to the technical field of batteries, the pole assembly comprises a pole main body, a sleeve and an insulating layer, the side wall of the sleeve is connected with the end part of the pole main body, and the insulating layer coats the outer side wall of the sleeve. According to the invention, the sleeve is arranged on the pole main body, the sleeve can be used for mounting the busbar, the sleeve and the busbar do not need to be welded, subsequent disassembly and maintenance can be facilitated, in addition, the insulating layer wrapping the sleeve can further prevent short circuit caused by contact between the sleeve and a conductive substance in the use process of the battery, and the insulating property of the pole assembly is improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to an electrode assembly and a battery cell. Background Technology

[0002] Lithium-ion batteries, as efficient and environmentally friendly energy storage devices, are widely used in power and energy storage fields. In existing lithium-ion battery designs, whether for power or energy storage, most cells employ a convex terminal design. These terminals typically protrude from the cell cover and are quadrilateral or circular in shape. In practical applications, the cells need to be welded together via busbars to form modules, meeting the requirements of different application scenarios.

[0003] However, existing protruding terminal block designs have some problems. First, the terminal block is prone to direct contact with conductive materials during production, transportation, and use, thus posing a short circuit risk. Second, during module manufacturing, accidental contact of metal parts or foreign matter such as metal particles generated during welding may also increase the short circuit risk. Utility Model Content

[0004] Several embodiments in this application propose a terminal assembly and a battery cell, which aim to reduce the risk of short circuits in batteries during production, transportation and use.

[0005] One embodiment of this application provides a pole post assembly, comprising:

[0006] pole body;

[0007] A sleeve, the sidewall of which is connected to the end of the pole body; and

[0008] An insulating layer that covers the outer wall of the sleeve.

[0009] In one embodiment, the sleeve has a mounting hole for connecting a busbar.

[0010] In one embodiment, the insulating layer has a cylindrical structure and forms a receiving cavity with openings at both ends. The sleeve is disposed in the receiving cavity, and the insulating layer has a clearance opening facing the electrode body. The electrode body passes through the clearance opening.

[0011] In one embodiment, the pole body has a concave arc surface facing the sleeve, and the concave arc surface is connected to the side wall of the sleeve; or

[0012] The pole body and the sleeve are integrally formed.

[0013] In one embodiment, the thickness of the insulating layer is greater than or equal to 0.5 mm and less than or equal to 3 mm; and / or

[0014] The distance between the inner peripheral wall of the mounting hole and the outer peripheral wall of the sleeve is greater than or equal to 1 mm and less than or equal to 5 mm.

[0015] In one embodiment, the mounting hole is coaxially disposed with the sleeve and extends through the sleeve, and the mounting hole is exposed at both ends of the insulating layer.

[0016] In one embodiment, the inner wall of the mounting hole is provided with internal threads.

[0017] In one embodiment, the inner wall of the mounting hole is provided with a snap-fit ​​portion.

[0018] In one embodiment, the sleeve is prismatic, cylindrical, or irregularly shaped.

[0019] An embodiment of this application also provides a battery cell including a housing, a cover plate, an inner core, and an electrode assembly as described above, wherein the housing forms a receiving cavity, the inner core is disposed in the receiving cavity, and the electrode assembly is disposed on the cover plate.

[0020] In several embodiments provided in this application, a sleeve is provided on the terminal block body, and an insulating layer is wrapped around the outer wall of the sleeve. This provides insulation protection for the terminal block assembly, simplifies the installation of the busbar, and reduces the short-circuit risk of individual battery cells. Specifically, the terminal block assembly includes a terminal block body, a sleeve, and an insulating layer. During the packaging of individual battery cells into modules, the mounting holes formed by the sleeve allow for the installation of the busbar, eliminating the need to weld the busbar and the terminal block. This facilitates subsequent disassembly and maintenance and avoids the short-circuit risk caused by welding slag. The insulating layer covering the sleeve further prevents short circuits caused by contact between the sleeve and conductive materials during battery use, improving the insulation performance of the terminal block assembly. Moreover, the insulating layer also provides physical protection for the sleeve, preventing oxidation and extending the service life of the terminal block assembly. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments or prior art of this application, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 A cross-sectional structural schematic diagram of an embodiment of the pole post assembly provided in this application;

[0023] Figure 2 This is a schematic diagram of the structure of a single battery cell provided in this application;

[0024] Figure 3 This is a schematic diagram of the structure of the first embodiment of the pole post assembly provided in this application;

[0025] Figure 4 This is a schematic diagram of the structure of the second embodiment of the pole assembly provided in this application.

[0026] Explanation of icon numbers:

[0027] 100. Terminal assembly; 1. Terminal body; 1a. Mounting hole; 1b. Concave arc surface; 2. Sleeve; 21. Internal thread; 22. Snap-fit ​​part; 3. Insulating layer; 200. Battery cell; 210. Top cover; 211. First seal; 212. Second seal; 210a. Electrode lead-out hole; 220. Inner core. Detailed Implementation

[0028] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of several embodiments. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0029] It should be noted that if directional indications (such as up, down, left, right, front, back, etc.) are involved in multiple embodiments of this application, the directional indications are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0030] Furthermore, if multiple embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text implies three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0031] In existing lithium-ion battery designs, most battery terminals adopt a convex design. However, this convex terminal design presents several problems. First, the terminals are prone to direct contact with conductive materials during production, transportation, and use, potentially leading to short circuits. Second, during module manufacturing, accidental contact between metal parts or foreign matter such as metal particles generated during welding can also increase the risk of short circuits.

[0032] To address the aforementioned problems, this application proposes a pole assembly to solve the technical issues mentioned above.

[0033] Please see Figures 1 to 4 The terminal assembly in this embodiment is used to input current to the battery cell 200 and output current from the battery cell 200. It includes a terminal body 1, a sleeve 2 and an insulating layer 3. The side wall of the terminal body 1 is connected to the end of the sleeve 2, and the insulating layer 3 covers the outer side wall of the sleeve 2.

[0034] During the assembly of individual battery cells into battery modules or battery packs, the individual battery cells 200 are typically electrically connected via busbars. A busbar is a low-resistance conductive metal strip, usually made of copper or aluminum, used to connect multiple battery cells 200 in series or parallel. In series connection, the busbar connects the positive terminal of battery cell 200 to the negative terminal of the next cell, thereby accumulating voltage; while in parallel connection, the busbar connects the positive and negative terminals of multiple battery cells 200 respectively to increase capacity and maintain a constant voltage. Through the connection of busbars, current can be efficiently transferred between battery cells 200, while reducing resistance and energy loss at connection points, ensuring good current conduction performance and stability of the battery pack during charging and discharging.

[0035] It is understood that the mounting hole 1a on the sleeve 2 is used for mounting the busbar to achieve series and / or parallel connection between the individual battery cells 200. The presence of the mounting hole 1a allows the busbar to have a mounting base on the sleeve 2, thus eliminating the need for welding. It should be noted that the mounting hole 1a can extend in a direction parallel to the top cover 210, or in a direction perpendicular to the top cover 210, or in a direction obliquely upward relative to the top cover 210. This application does not impose any restrictions on this, and adjustments can be made flexibly according to the actual usage requirements of the battery. For example, in one embodiment of this application, the mounting hole 1a is set parallel to the top cover 210. For details, please refer to further reference. Figure 2 Both sleeves 2 have mounting holes 1a, and the two mounting holes 1a are coaxially arranged to facilitate the installation of the busbar; alternatively, the two sleeves 2 can also be non-coaxial, that is... Figure 2The two sleeves 2 shown are rotated 90° around an axis perpendicular to the top cover 210, so that the axes of the two mounting holes 1a are parallel, thus avoiding interference between the busbars connecting the positive and negative terminals during the lead-out process. For example, when the battery cell 200 needs to be integrated into a module with smaller space requirements, its space occupation should be fully considered. In this embodiment, by using mounting holes 1a extending perpendicular to the top cover 210, the overall height of the battery cell 200 can be further reduced. In this embodiment, the mounting hole 1a can adopt a recessed design, that is, the sleeve 2 is slightly higher than or no higher than the upper surface of the top cover 210 along the height direction of the battery cell 200, and the mounting hole 1a is opened in the sleeve 2, so that the mounting hole 1a is at least partially located below the upper surface of the top cover 210, thereby reducing the volume occupied by the battery cell 200.

[0036] To accommodate the shape and structure of sleeve 2, the insulating layer 3 is cylindrical in shape, with a hollow interior forming a cavity open at both ends. Sleeve 2 is disposed within this cavity. For details, please refer to further documentation. Figure 1 and Figure 3 Since the sleeve 2 needs to connect with the terminal body 1 to realize the input and output of current, the insulating layer 3 has a clearance opening on the side facing the top cover of the battery cell. The design size and shape of the clearance opening are adapted to the specific size and shape of the terminal body 1 so that the terminal body 1 can pass through the clearance opening and connect with the sleeve 2. It can be understood that, in order to further optimize the protection of the sleeve 2, the length of the insulating layer 3 can be slightly longer than the length of the sleeve 2, so that both ends of the insulating layer 3 can be rolled to cover the opening edge area of ​​the mounting hole 1a of the sleeve 2, thereby achieving more reliable protection.

[0037] In several embodiments provided in this application, mounting holes 1a are provided on the sleeve 2 and an insulating layer 3 is wrapped around its outer surface. This provides insulation protection for the sleeve 2, simplifies the installation of the busbar, and reduces the short-circuit risk of the battery cell 200. Specifically, the terminal assembly includes the sleeve 2 and the insulating layer 3. During the packaging of the battery cell 200 into a module, the mounting holes 1a on the sleeve 2 can be used for busbar installation, thus eliminating the need to weld the busbar and the sleeve 2, simplifying the assembly process, and avoiding the short-circuit risk caused by welding slag. The insulating layer 3 covering the sleeve 2 further prevents short circuits caused by the sleeve 2 coming into contact with conductive materials during battery use, improving the insulation performance of the terminal assembly. Moreover, the insulating layer 3 also provides physical protection for the sleeve 2, preventing oxidation and extending the service life of the terminal assembly.

[0038] It should be noted that the mounting hole 1a can be used to fix the busbar by snap-fit ​​or by screw. This application does not limit the way the mounting hole 1a is fitted to the busbar. For details, please refer to the first embodiment of this application. Figure 3 In this embodiment, the inner circumferential wall of the mounting hole 1a is provided with an internal thread 21. Correspondingly, the connecting end of the busbar is also provided with an external thread that mates with the internal thread 21. By screwing the connecting end of the busbar into the mounting hole 1a, the busbar is threadedly connected to the sleeve 2. In this embodiment, a mechanical fixing method is adopted, which can significantly improve the reliability and stability of the connection compared with traditional welding, especially in vibration or impact environments, effectively preventing the connection from loosening or breaking. Secondly, the threaded connection facilitates installation and disassembly, eliminating the need for complex welding equipment and processes, thus reducing production costs and maintenance difficulty. In addition, the threaded connection avoids thermal damage that may occur during welding, helping to protect the material properties of the terminal assembly and the busbar, and extending its service life. It also avoids short circuits caused by welding slag spatter during welding. At the same time, this connection method can also enhance the stability of the electrical connection, reduce contact resistance, and improve the overall performance and safety of the battery pack.

[0039] In the second embodiment of this application, specifically, please refer to further details. Figure 4 Multiple snap-fit ​​parts 22 are evenly spaced on the inner circumferential wall of the mounting hole 1a. Correspondingly, the connecting end of the busbar also has a corresponding snap-fit ​​groove. When the connecting end extends into the mounting hole 1a, it is fixed until the snap-fit ​​part 22 snaps into the groove. The snap-fit ​​method eliminates the need for complex welding or threading, simplifying the production process and reducing production costs and manufacturing difficulty. Secondly, the snap-fit ​​fixation enables quick connection and disassembly of the busbar and the terminal post, improving assembly efficiency and facilitating maintenance and replacement. At the same time, the snap-fit ​​structure achieves a stable electrical connection through mechanical interlocking, avoiding thermal damage and material performance degradation that may occur from welding, ensuring the reliability and durability of the connection. In addition, the snap-fit ​​fixation can effectively reduce contact resistance, improve current transmission efficiency, and enhance the overall safety of the battery pack.

[0040] Furthermore, the first embodiment mentioned above can also be combined with the second embodiment. That is, an internal thread 21 is provided on the inner sidewall of the mounting hole 1a of the sleeve 2, and a snap-fit ​​part 22 is provided at the end of the internal thread 21. During specific assembly, the connecting end of the busbar is screwed into the mounting hole 1a by means of a screw until it is rotated to the preset assembly position. The snap-fit ​​part 22 engages with the snap-fit ​​groove of the busbar to achieve a limiting action. This combines the convenience of disassembly and assembly of the threaded connection with the installation stability of the snap-fit, thereby making it less likely for the pole assembly to loosen after being connected to the busbar. It is understood that the mounting hole 1a can be a blind hole or a through hole. This application does not limit this. In one embodiment of this application, the mounting hole 1a is configured as a through hole. Through holes can simplify the processing technology and reduce manufacturing costs because the processing of through holes is relatively simple and does not require complex drilling or milling processes. Secondly, through holes can provide better heat dissipation performance, allowing air or other cooling media to pass through, thereby effectively reducing the temperature of the component during operation and extending its service life. Furthermore, the through-hole design facilitates installation and maintenance, allowing for easy insertion or replacement of connectors used for electrical connections, thus improving assembly efficiency. In electrical connections, through-holes also reduce stress concentration, enhance structural stability, provide a more direct conduction path for current, reduce contact resistance, and improve electrical performance.

[0041] In another embodiment of this application, the mounting hole 1a of the sleeve 2 and the connecting end of the busbar are fitted with an interference fit, that is, the outer diameter of the connecting end is slightly larger than the inner diameter of the mounting hole 1a to achieve a tight connection. During assembly, the connecting end of the busbar is forcibly pressed into the mounting hole 1a, and elastic deformation is generated by the interference between the two, thereby forming a tight mechanical connection. This connection method does not require additional fasteners or welding and can provide high connection strength and good conductivity. To ensure the reliability of the interference fit, the design of the hole diameter and the outer diameter of the connecting end needs to be precisely calculated, and the specific values ​​depend on the material and size. The elastic modulus and yield strength of the material also affect the selection of the interference to ensure that the material is not deformed or damaged during assembly, while ensuring the stability and conductivity of the connection.

[0042] In the technical solution of this application, the outer surface of the sleeve 2 is covered with an insulating layer 3. For details, please refer to further reference. Figure 1The insulating layer 3 is a structure used to provide insulation and physical protection for the sleeve 2. It should be noted that the insulating layer 3 can be applied to the outer surface of the sleeve 2 by adhesive bonding or by a coating process. This application does not impose any restrictions on this. In one embodiment of this application, the insulating layer 3 is bonded to the sleeve 2 layer by layer using adhesive bonding, exposing the opening of the mounting hole 1a to facilitate the installation of the busbar. Bonding the insulating layer 3 is convenient for construction and is not limited by the external shape of the sleeve 2; simply applying the insulating layer 3 along the outer shape of the sleeve 2 achieves full coverage. Alternatively, if it is necessary to improve the overall integrity of the sleeve 2 and the insulating layer 3, a coating process can be considered. Specifically, the insulating material is coated onto the outer surface of the sleeve 2 by injection molding or hot pressing to form a uniform insulating layer 3. This process ensures a tight bond between the insulating layer 3 and the pole, while providing good sealing and mechanical strength. The advantages of using a rubber coating process are twofold. First, it effectively improves the insulation performance of the terminal, preventing short circuits and leakage risks. Second, the rubber coating process protects the terminal from external environmental corrosion and mechanical damage, extending its service life. Furthermore, the rubber coating process also provides a superior appearance.

[0043] It should be noted that the material of insulation layer 3 can be PC (polycarbonate), PE (polyethylene), or PP (polypropylene), depending on the specific requirements. PC has excellent mechanical strength and impact resistance, and high transparency, making it suitable for applications requiring high protection levels and visibility. PE (especially LDPE) is soft, tough, chemically stable, and low-cost, helping to reduce the overall material cost of the battery, making it suitable for scenarios requiring flexibility and chemical corrosion resistance. PP is lightweight, heat-resistant, and chemically resistant, contributing to lightweight battery design. All three materials possess good insulation properties, and the appropriate material can be selected based on specific needs to achieve optimal insulation performance and product performance.

[0044] It is understandable that the thickness of the insulation layer 3 can be adjusted adaptively according to the actual needs of the product. Its thickness is generally between 0.5mm and 3mm. If the terminal assembly is used in a battery with high requirements for lightweighting, the mass ratio of each part should be considered, and the thickness of the insulation layer 3 should be appropriately adjusted to reduce the material of the insulation layer 3, thereby reducing its mass. In this embodiment, the thickness of the insulation layer 3 should be between 0.5mm and 1mm. The specific thickness parameters should be adaptively designed and adjusted according to the actual situation. If the terminal assembly is used in a battery with high requirements for overall insulation and physical protection, the thickness of the insulation layer 3 should be increased. The thickness of the insulation layer 3 is preferably between 1mm and 3mm. When the thickness of the insulation layer 3 is increased, the overall structural strength of the terminal assembly will also be improved.

[0045] To ensure the structural strength of the sleeve 2, the opening radius of the mounting hole 1a should be designed according to the specific dimensions of the sleeve 2. This application does not limit the size of the radius of the mounting hole 1a, but it should ensure that the thickness of the sleeve 2 in the circumferential direction of the mounting hole 1a is not less than 1mm, so as to ensure that the material strength of the sleeve 2 is sufficient to resist deformation when subjected to force. Specifically, the distance between the inner circumferential wall of the mounting hole 1a and the outer circumferential wall of the sleeve 2 is maintained between 1mm and 5mm. During production design, the thickness of the sleeve 2 can be adjusted according to actual needs. For example, when the design radius of the mounting hole 1a is large, the thickness of the sleeve 2 should be designed to be as thick as possible to prevent the busbar connection end from generating deformation force on the sleeve 2 after being installed in the mounting hole 1a, which would cause the sleeve 2 to deform or bend. If the radius of the mounting hole 1a is small, the sleeve 2 can be thinned to achieve a lightweight design of the pole assembly while ensuring its structural strength.

[0046] It should be noted that the sleeve 2 can be prismatic, cylindrical, or other irregular columnar shapes. This application does not limit this. In one embodiment of this application, the sleeve 2 is cylindrical, and the axis of the cylindrical sleeve 2 is parallel to the plane of the top cover 210. The cylindrical structure has high symmetry and uniformity in mechanical properties, and can better withstand stress from all directions, thereby improving the structural strength and stability of the sleeve 2. Secondly, the cylindrical pole is relatively simple to process and manufacture, and it is easy to achieve high-precision dimensional control, which helps to reduce production costs and improve production efficiency. In addition, the connection method between the cylindrical sleeve 2 and the busbar is more flexible and diverse. It can be conveniently connected by threaded connection, snap-fit, or interference fit, etc., which enhances the adaptability of the sleeve 2 in different application scenarios. At the same time, the surface of the cylindrical pole is smooth, which can reduce friction and wear with surrounding components and extend service life. The axis of the cylindrical sleeve 2 is parallel to the plane of the top cover 210 and is external to the shell. This layout is conducive to optimizing the space utilization inside the battery pack and improving the overall integration and energy density of the battery pack.

[0047] In one embodiment of this application, the sleeve 2 is externally positioned outside the receiving cavity. To enable the sleeve 2 to connect with the inner core 220 of the battery cell 200 for electrical conductivity, the electrode assembly also includes an electrode body 1. For details, please refer to further details. Figure 1 and Figure 2One end of the electrode post body 1 extends into the housing cavity and connects to the internal winding core. Correspondingly, the top cover 210 has an electrode lead-out hole 210a connecting the housing cavity and the outside. The upper and lower openings of the electrode lead-out hole 210a are respectively provided with a first sealing element 211 and a second sealing element 212. In addition to their sealing function, the first sealing element 211 and the second sealing element 212 can also prevent the electrode post assembly 100 from contacting the top cover 210 and causing a short circuit. The electrode post body 1 extends into the housing through the electrode lead-out hole 210a and connects to the inner core 220. It should be noted that the inner core 220 can be a wound core or a stacked core. This application does not limit this. The inner core 220 is usually composed of a positive electrode sheet, a negative electrode sheet, and a separator, assembled together by winding or stacking. Its main function is to store and release electrical energy. When the battery is working, the chemical reaction inside the wound core converts chemical energy into electrical energy, which is then transferred to the external circuit through the electrode post assembly. To simplify the machining and assembly process, the pole body 1 and the sleeve 2 are integrally formed. The pole body 1 and the sleeve 2 are made of the same material, typically aluminum or copper, which are conductive metals. They are usually machined using precision machining equipment such as CNC lathes and milling machines to achieve the desired finish. Figure 1 The irregular structure shown is an example. Alternatively, it can be manufactured using a stamping process, which allows for rapid prototyping through die stamping and is suitable for mass production. The choice of these processes depends on the material, shape complexity, and production scale of the terminal block, ensuring that the mechanical strength, conductivity, and insulation performance of the terminal block assembly meet the battery design requirements.

[0048] This application also proposes a battery cell 200, which includes an inner core 220, a housing, a cover plate, and a terminal assembly 100 as described above. The housing forms a receiving cavity, the inner core 220 is disposed in the receiving cavity, and the terminal assembly 100 is disposed on the cover plate. The specific structure of the terminal assembly is as described in the above embodiments. Since this battery cell 200 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0049] It is understood that by electrically connecting and arranging the aforementioned multiple battery cells 200 according to a certain pattern, a battery pack can be obtained. This battery pack includes a battery pack casing, a busbar, and multiple battery cells 200 provided in this application. The multiple battery cells 200 are installed inside the battery pack casing in a parallel arrangement or array arrangement and are electrically connected through the busbar. The busbar is installed and fixed in the mounting hole 1a of the sleeve 2 using connection methods such as screwing, snap-fitting, or interference fit. This battery pack can be used as a power source for electrical devices or as an energy storage unit for electrical devices. Electrical devices can include mobile devices (e.g., mobile phones, laptops), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, range-extended vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc., but are not limited to these.

[0050] The above description is merely an exemplary embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the technical concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A pole assembly, characterized by include: The main body of the pole column (1); Sleeve (2), the side wall of which is connected to the end of the pole body (1); as well as An insulating layer (3) is provided, which covers the outer wall of the sleeve (2).

2. The pole assembly of claim 1, wherein The sleeve (2) has a mounting hole (1a) for connecting a busbar.

3. The pole assembly as described in claim 2, characterized in that, The thickness of the insulating layer (3) is greater than or equal to 0.5 mm and less than or equal to 3 mm; and / or The distance between the inner peripheral wall of the mounting hole (1a) and the outer peripheral wall of the sleeve (2) is greater than or equal to 1 mm and less than or equal to 5 mm.

4. The pole assembly as described in claim 2, characterized in that, The mounting hole (1a) is coaxially arranged with the sleeve (2) and passes through the sleeve (2), and the mounting hole is exposed at both ends of the insulating layer (3).

5. The pole assembly as described in claim 4, characterized in that, The inner wall of the mounting hole (1a) is provided with an internal thread (11).

6. The pole assembly of claim 4, wherein The inner wall of the mounting hole (1a) is provided with a snap-fit ​​part (12).

7. The pole assembly of any one of claims 1 to 6, wherein, The insulating layer (3) has a cylindrical structure and forms a receiving cavity with openings at both ends. The sleeve (2) is located in the receiving cavity. The insulating layer (3) has a clearance opening facing the pole body (1). The pole body (1) passes through the clearance opening.

8. The pole assembly as described in any one of claims 1 to 6, characterized in that, The pole body (1) has a concave arc surface (1b) facing the sleeve (2), and the concave arc surface (1b) is connected to the side wall of the sleeve (2); or The pole body (1) and the sleeve (2) are integrally formed.

9. The pole assembly as described in any one of claims 1 to 6, characterized in that, The sleeve (2) is prismatic, cylindrical, or irregularly shaped.

10. A single battery cell (200), characterized in that, The device includes a housing, a cover plate, an inner core (220), and an electrode assembly as described in any one of claims 1 to 9, wherein the housing forms a receiving cavity, the inner core (220) is disposed in the receiving cavity, and the electrode assembly is disposed on the cover plate.

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