Lithium ion cell and power battery
The detachable connection design of the tenon head and the tenon groove structure solves the problems of maintenance convenience and high maintenance cost of lithium-ion battery modules or battery packs, and realizes convenient replacement and stable connection of battery cells.
Patent Information
- Application Number
- CN202422716770.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-07
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2034-11-07
AI Technical Summary
Existing lithium-ion battery modules or battery packs need to be completely disassembled for repair when the battery cells are damaged, resulting in reduced repair convenience and high maintenance costs.
The detachable mechanical connection design of the tenon and tenon groove structure is adopted. Through the cooperation of the tenon and tenon groove structure, the lithium-ion battery cell and the busbar can be detachably connected, allowing damaged battery cells to be replaced individually.
The maintenance convenience of the battery module or battery pack is improved, the maintenance cost is reduced, and the detachability and stability of the battery cell are enhanced.
Smart Images
Figure CN223347963U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of power batteries, and in particular to a lithium-ion battery cell and a power battery. Background Art
[0002] A power battery is a power source that provides power for vehicles, currently primarily referring to batteries in new energy vehicles. Lithium-ion cells are the basic unit of power batteries, typically lithium-ion batteries. Power batteries can be composed of multiple lithium-ion cells connected in series and parallel to meet high voltage and large capacity requirements. To provide sufficient voltage and capacity to power electric vehicles, multiple cells need to be combined into modules or CTP battery packs. During the assembly of lithium-ion cells into battery modules or CTP battery packs, welding is commonly used to interconnect and secure the individual cells via busbars in series, parallel, or series-parallel-parallel configurations. This ensures the electrical connection stability and proper operation of the module or battery pack.
[0003] However, since multiple lithium-ion battery cells are fixedly connected to a busbar by welding to form a module or battery pack, when one or more battery cells in the module or battery pack are damaged and the module or battery pack cannot be used, the entire module or battery pack needs to be disassembled and repaired, and the busbar and abnormal battery cells need to be replaced, which reduces the maintenance convenience of the module or battery pack and increases the maintenance cost. Utility Model Content
[0004] The present application provides a lithium-ion battery cell and a power battery to solve the problems of reduced maintenance convenience and high maintenance costs of current modules or battery packs.
[0005] In the first aspect, the present application provides a lithium-ion battery cell, comprising: a bare battery cell, a top cover and a shell, the top cover and the shell enclosing to form a accommodating cavity, and the bare battery cell is located in the accommodating cavity; the top cover comprises a top cover body, and a pole structure is provided on the top cover body; the pole structure comprises a tenon head and a tenon groove structure, the tenon groove structure is provided through the top cover body, and the tenon head and the tenon groove structure cooperate to form a detachable connection.
[0006] With this solution, the top cover and shell together form the exterior structure of the lithium-ion battery cell, enclosing a cavity for accommodating the bare battery cell. Because the tenon is connected to the external busbar, the lithium-ion battery cell can be integrated into a battery module or battery pack. The tenon and the mortise-and-tenon structure form a detachable mechanical connection, allowing the pole structure to be disassembled when needed for easier maintenance and replacement, improving maintenance efficiency and reducing maintenance costs.
[0007] In a possible design, the tenon portion includes a welding portion and a flange portion connected to the welding portion, the welding portion can form a welding connection with the external busbar, and the flange portion can cooperate to extend into the interior of the tenon-groove structure to form a detachable connection.
[0008] With the above solution, the welding portion is part of the tenon head and is designed to be welded to the external busbar, providing a stable electrical connection. The flange portion is another part of the tenon head, which is connected to the welding portion and can extend into the tenon-groove structure. The cooperation between the flange portion and the tenon-groove structure ensures that the flange portion can be smoothly inserted and form a detachable connection, facilitating the removal of the pole structure when necessary, thereby allowing maintenance and replacement of the battery cell.
[0009] In a possible design, the tongue and groove structure includes an elastic portion, which is fixedly disposed within the tongue and groove structure, and the flange portion can be clamped within the elastic portion to form a detachable connection with the elastic portion.
[0010] With the above solution, an elastic portion is provided within the tongue-and-groove structure, allowing the flange portion to be snapped into place within the elastic portion, forming a detachable connection. Furthermore, the outer periphery of the sidewall of the tongue-and-groove structure forms a sealed connection with the main body of the top cover. This allows the tongue-and-groove structure to achieve both a sealed connection with the top cover and a detachable connection with the flange portion. This design makes the top cover as a whole strong and reliable, while also providing a certain degree of flexibility and detachability, facilitating maintenance and replacement.
[0011] In one possible design, the elastic portion includes a bottom substrate, a movable waist plate and a clamping plate. The movable waist plate is fixedly arranged along the outer periphery of the bottom substrate to form a mortise, and the shape of the mortise matches the shape of the flange portion; the flange portion has an insertion end and a clamping end away from the insertion end, and the cross-sectional diameter of the flange portion gradually increases from the clamping end to the insertion end; the cross-sectional diameter of the mortise gradually increases from the entrance of the mortise to the bottom substrate; the flange portion is inserted along the entrance of the mortise in the direction of the bottom substrate, and when the flange portion is inserted into the mortise, the clamping end of the mortise is clamped by the entrance of the mortise.
[0012] Through the above solution, the flange portion has an insertion end and a snap-on end. The insertion end is used to insert into the mortise, while the snap-on end is used to form a snap connection with the snap-on plate of the mortise. The cross-sectional diameter of the mortise gradually increases from the entrance to the bottom substrate, matching the change in the cross-sectional diameter of the flange portion, so that the flange portion can gradually be "locked" in the mortise when inserted into the mortise. This self-locking mechanism ensures the stability of the connection and prevents the flange portion from accidentally falling off due to vibration or impact. The flange portion is inserted toward the bottom substrate along the entrance of the mortise. When the flange portion is inserted into the mortise, the snap-on end of the mortise is caught by the entrance of the mortise, achieving snap connection. This snap-on method provides a secure connection while allowing the flange portion to be disassembled through appropriate operations when necessary.
[0013] In a possible design, the insertion end is provided with an inclined surface, which enables the flange portion to be inserted from the entrance of the mortise.
[0014] Through the above solution, when the flange portion is inserted into the mortise, the bevel first contacts the side wall of the mortise. Due to the design of the bevel, this can reduce the force required for insertion, making the entire insertion process smoother. The presence of the bevel also helps to guide the flange portion to correctly align with the mortise, reducing the risk of misalignment or jamming. Even if the cross-sectional diameter of the flange portion gradually increases from the clamping end to the insertion end, the design of the bevel allows the flange portion to be easily inserted in the initial stage. Once it passes through the bevel portion, the increase in the diameter of the flange portion will cause it to be clamped in the mortise, achieving self-locking. The design of the insertion end being provided with a bevel balances the convenience of insertion and the stability of the connection.
[0015] In one possible design, the clip plate is fixed at the entrance of the mortise, the clip plate is fixed on the outside of the mortise and extends toward the mortise structure, or the clip plate is fixed on the inside of the mortise and extends away from the mortise structure.
[0016] With this solution, the clip plate is fixed to the outside of the mortise and extends toward the mortise structure. In this design, when the flange is inserted into the mortise, its clipping end contacts and becomes locked in place by the clip plate. Because the clip plate extends toward the mortise structure, it forms a barrier outside the mortise, preventing the flange from slipping out of the mortise. The clip plate provides additional support outside the mortise, enhancing the stability of the connection.
[0017] The clip plate is fixed to the inside of the mortise and extends away from the mortise structure. In this design, the clipping end of the flange is captured by the clip plate after being inserted into the mortise. The clip plate forms a reverse barrier inside the mortise, preventing the flange from easily dislodging. The clip plate's placement inside the mortise makes the overall structure more compact, reduces external protrusions, and is more suitable for applications with limited space.
[0018] Each of these two methods of securing the clip plate has its advantages, and the choice depends on specific application requirements and design considerations. The first method may be more suitable for scenarios requiring higher stability and ease of operation, while the second method may be more suitable for applications with limited space or requiring a concealed clip mechanism. The appropriate clip plate securing method can be selected based on factors such as the specific battery cell usage environment, maintenance requirements, and manufacturing costs.
[0019] In a possible design, conductive adhesive is provided between the flange portion and the movable waist plate.
[0020] The conductive adhesive described above is an adhesive that exhibits a certain degree of conductivity after curing or drying. It is primarily composed of a base resin and a conductive filler (such as metal powder). The base resin's bonding action binds the conductive particles together, forming a conductive path and achieving a conductive connection between the bonded materials. By placing the conductive adhesive between the flange and the movable waist plate, a stable conductive connection is achieved while also providing excellent mechanical bonding.
[0021] In one possible design, the pole structure includes a positive pole structure for electrically connecting to the positive pole piece on the bare battery cell and a negative pole structure for connecting to the negative pole piece on the bare battery cell; the mortise and tenon structure includes a bottom plate and a side wall, the bottom plate can be connected to the positive pole piece or the negative pole piece on the bare battery cell, and the outer periphery of the side wall forms a sealed connection with the top cover body.
[0022] Through the above scheme, the pole structure on the top cover includes a positive pole structure and a negative pole structure. The positive pole structure and the negative pole structure are electrically connected to the positive pole sheet and the negative pole sheet on the bare battery cell respectively. The sealed connection between the side wall and the top cover body helps to protect the interior of the battery cell from being affected by the external environment.
[0023] In one possible design, the top cover further includes an upper plastic member, a lower plastic member, and a sealing ring. The upper plastic member is positioned above the outer periphery of the sidewall of the tongue-and-groove portion, while the lower plastic member is positioned below the outer periphery of the sidewall of the tongue-and-groove portion. The sealing ring is positioned between the upper and lower plastic members. The top cover further includes an explosion-proof structure and a sealing member, which are positioned on the main body of the top cover.
[0024] Through the above solution, the upper and lower plastics, along with the sealing ring, form the sealing structure of the battery cell top cover. This structure effectively protects the electrical components within the battery cell and extends the battery cell's service life. The design of the sealing structure must take into account the sealing requirements of the battery cell in different operating environments, including factors such as temperature fluctuations, pressure changes, and chemical corrosion.
[0025] Explosion-proof structures are a crucial component of battery safety design. When abnormal conditions cause internal pressure to rise within the battery, the explosion-proof structure promptly opens, releasing the internal pressure and preventing explosion, thereby protecting the battery and the surrounding environment. The injection port is the channel for injecting electrolyte during battery manufacturing. After injection, the port must be sealed to prevent electrolyte leakage and the intrusion of external contaminants. The seal design prevents the buildup of metal particles and burrs that could enter the battery and cause a short circuit. The use of seals ensures internal battery cleanliness, improving battery reliability and safety.
[0026] In a second aspect, the present application provides a power battery comprising a busbar and any of the above-mentioned lithium-ion battery cells, wherein the tenon portion can be connected to the busbar so that the lithium-ion battery cell is connected to the busbar.
[0027] The beneficial effects of the power battery provided in the second aspect and each possible design of the second aspect can be referred to the beneficial effects brought about by the first aspect and each possible implementation method of the first aspect, and will not be repeated here.
[0028] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to more clearly understand the technical means of the embodiments of the present application, they can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiments of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present application, a brief introduction will be given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0030] Figure 1 Schematic diagram of a lithium-ion battery cell provided in one embodiment of the present application.
[0031] Figure 2 This is an exploded view of a lithium-ion battery cell provided in one embodiment of the present application.
[0032] Figure 3 This is a schematic diagram of the top cover of a lithium-ion battery cell provided in one embodiment of the present application.
[0033] Figure 4 for Figure 3 A cross-sectional view of the top cover of the lithium-ion battery cell provided in the figure along the A-A1 direction.
[0034] Figure 5 for Figure 3 A partial magnified view of area D in the middle.
[0035] Figure 6 This is a schematic diagram of an elastic portion provided in an embodiment of the present application.
[0036] Figure 7 for Figure 6 A schematic diagram of the elastic portion from another perspective is provided.
[0037] Figure 8 for Figure 7 A cross-sectional view of the elastic portion along the B-B1 direction is provided.
[0038] Figure 9 This is a schematic diagram of an elastic portion provided in another embodiment of the present application.
[0039] Figure 10 for Figure 9 A schematic diagram of the elastic portion from another perspective is provided.
[0040] Figure 11 for Figure 10 A cross-sectional view of the elastic portion along the C-C1 direction is provided.
[0041] Explanation of the reference numerals: 100, top cover body; 110, upper plastic; 120, lower plastic; 130, explosion-proof structure; 140, seal; 150, sealing ring; 200, shell; 201, bare cell; 202, tab; 203, insulating member; 210, connecting piece; 300, pole structure; 310, tenon; 320, tongue and groove structure; 321, bottom plate; 322, side wall; 311, welding part; 312, flange; 313, inclined plane; 330, elastic part; 331, bottom substrate; 332, movable waist plate; 333, snap-in plate; D area; section line A-A1; section line B-B1; section line C-C1. DETAILED DESCRIPTION
[0042] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification, claims and drawings of this application are intended to cover non-exclusive inclusions.
[0044] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase "embodiment" in various places in the specification does not necessarily refer to the same embodiment, nor does it necessarily refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0045] The term "and / or" in this document simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists, A and B exist, and B exists. Additionally, the character " / " in this document generally indicates that the related objects are in an "or" relationship.
[0046] The directional words appearing in the following description are all directions shown in the drawings and do not limit the specific structure of the lithium-ion battery cells of this application. For example, in the description of this application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., which indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting this application.
[0047] In addition, the terms "first", "second", etc. in the description and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order, and may explicitly or implicitly include one or more such features.
[0048] In the description of this application, unless otherwise specified, "plurality" means more than two (including two), and similarly, "multiple groups" means more than two (including two).
[0049] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, the "connection" or "connection" of a mechanical structure may refer to a physical connection. For example, the physical connection may be a fixed connection, such as a fixed connection through a barrier, such as a fixed connection through screws, bolts, or other barrier; the physical connection may also be a detachable connection, such as a mutual snap connection or snap connection; the physical connection may also be an integral connection, such as a connection formed by welding, bonding, or integral molding. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0050] Power batteries are based on lithium-ion cells (hereinafter referred to as cells) as basic units, combined into modules through various series and parallel connections. Multiple modules, combined with a battery management system, form a battery pack, which is ultimately installed in electric vehicles to provide power. Cells are the core component of power batteries, determining key performance factors such as energy density, power performance, safety, and lifespan.
[0051] As a core component of new energy vehicles, power batteries are commonly assembled from lithium-ion cells to form modules or CTP battery packs. The process of welding individual cells together via busbars in series, parallel, or both is commonly used to ensure electrical connection stability and proper operation of the module or battery pack. However, if one or more cells in a module or battery pack formed by welding multiple lithium-ion cells together become damaged or unusable, the entire module or battery pack must be disassembled and the busbar and abnormal cells replaced, reducing battery repairability and increasing maintenance costs.
[0052] In view of this, embodiments of the present application provide a lithium-ion battery cell and power battery. By designing the terminal structure in the top cover of the lithium-ion battery cell as a detachable mechanical connection comprising a tenon head and a tongue-and-groove structure, the terminal structure can be removed when necessary, facilitating maintenance and replacement. This improves maintenance efficiency and reduces maintenance costs.
[0053] Figure 1 Schematic diagram of a lithium-ion battery cell provided in one embodiment of the present application. Figure 2 This is a schematic diagram of an exploded view of a lithium-ion battery cell provided in one embodiment of the present application. Figure 3 This is a schematic diagram of the top cover of a lithium-ion battery cell provided in one embodiment of the present application. Figure 4 for Figure 3 The cross-sectional view of the top cover of the lithium-ion battery cell along the A-A1 direction is provided in the figure. Figures 1 to 4 In this embodiment, a lithium-ion battery cell is provided, including: a bare battery cell 201, a top cover, and a shell 200. The top cover and the shell 200 are enclosed to form a receiving cavity, and the bare battery cell 201 is located in the receiving cavity.
[0054] Please refer to Figure 1 The bare cell 201 is the basic component of the cell, including a positive electrode sheet, a negative electrode sheet, and an electrolyte and a separator between the positive electrode sheet and the negative electrode sheet.
[0055] The bare cell 201 in this embodiment is formed by stacking and winding the positive electrode sheet, the negative electrode sheet and the isolation film around the central axis, and the top of the bare cell 201 extends a tab 202, which is electrically connected to the connecting piece 210 by welding. The number of bare cells 201 in the accommodating cavity is at least one, and multiple bare cells 201 are connected to the connecting piece 210, and then an electrical connection is formed by connecting the connecting piece 210 and the pole in the top cover. An insulating member 203 is provided on the outside of the bare cell 201, and the bare cell 201 is wrapped by the insulating member 203 to insulate the bare cell 201 from the outer shell, thereby avoiding contact between the bare cell 201 and the outer shell to cause a short circuit in the cell.
[0056] The top cover and the shell 200 together constitute the external structure of the battery cell, and they enclose to form a receiving cavity for accommodating the bare battery cell 201.
[0057] The shell 200 is designed as a cavity structure with an opening on the top, so that the bare battery cell 201 can be wrapped inside the shell 200. By closing the top cover on the shell 200 and sealing it with the top cover, the bare battery cell 201 is isolated from the outside world or prevented from contacting the bare battery cell 201 with the external environment, causing the bare battery cell 201 to fail.
[0058] The top cover includes a top cover body 100, on which a pole structure 300 is arranged. The pole structure 300 includes a positive pole structure 300 for electrically connecting to the positive pole piece on the bare battery cell 201 and a negative pole structure 300 for connecting to the negative pole piece on the bare battery cell 201; the pole structure 300 includes a tenon head 310 and a tenon groove structure 320, the tenon head 310 can be connected to an external busbar (not shown), the tenon groove structure 320 is arranged through the top cover body 100, the tenon groove structure 320 includes a bottom plate 321 and a side wall 322, the bottom plate 321 can be connected to the positive pole piece or the negative pole piece on the bare battery cell 201, the outer periphery of the side wall 322 forms a sealed connection with the top cover body 100, and the tenon head 310 and the tenon groove structure 320 cooperate to form a detachable connection.
[0059] Through the above solution, the top cover and the shell 200 together constitute the external structure of the lithium-ion battery cell. They enclose to form a receiving cavity for accommodating the bare battery cell 201. The pole structure 300 on the top cover includes a positive pole structure 300 and a negative pole structure 300. The positive pole structure 300 and the negative pole structure 300 are electrically connected to the positive electrode sheet and the negative electrode sheet on the bare battery cell 201, respectively. The sealed connection between the side wall 322 and the top cover body 100 helps to protect the interior of the battery cell from the external environment. Because the tenon 310 is connected to the external busbar, the lithium-ion battery cell can be integrated into the battery module or battery pack, and the tenon 310 cooperates with the tongue and groove structure 320 to form a detachable mechanical connection. This design allows the pole structure 300 to be disassembled when necessary, facilitating maintenance and replacement. When one or more cells in a module or battery pack are damaged and the module or battery pack becomes unusable, there is no need to replace the busbar. Instead, the tenon head 310 and the tenon groove structure 320 need only be separated to replace the corresponding broken lithium-ion cells. This improves the maintenance convenience of the module or battery pack and reduces maintenance costs.
[0060] In this embodiment, the tenon portion 310 includes a welding portion 311 and a flange portion 312 connected to the welding portion 311. The welding portion 311 can form a welded connection with the external busbar, and the flange portion 312 can be inserted into the interior of the tongue-and-groove structure 320 to form a removable connection. The welding portion 311 provides a stable connection between the battery cell and the external busbar, while the design of the flange portion 312 allows for a removable connection to the bare battery cell 201.
[0061] The welding portion 311 is welded to the external busbar, so that the connection between the welding portion 311 and the external busbar provides a stable electrical connection. This welding connection can be performed by laser welding, ultrasonic welding, or resistance welding, etc. The specific method may depend on the corresponding welding technology in the battery cell manufacturing process.
[0062] The flange portion 312 is another part of the tenon portion 310, one end of which is fixed to the welding portion 311, and the other end is able to extend into the interior of the tenon structure 320. The cooperation between the flange portion 312 and the tenon structure 320 can ensure that the flange portion 312 can be smoothly extended and form a detachable connection, which is convenient for disassembling the pole structure 300 when necessary, so that the battery cell can be maintained and replaced.
[0063] In some embodiments, the flange portion 312 can be configured to have a resilient design to provide a certain degree of flexibility during the connection and removal process. The resilient design of the flange portion 312 can be configured to have a structure with a spring-back effect that allows the flange portion 312 to be inserted into and retained within the tongue-and-groove structure 320.
[0064] In some embodiments, the flange portion 312 may also include an elastic structural member sleeved on the outer periphery of the flange portion. The elastic structural member is a structural design with a rebound effect that can be inserted into and stuck in the tongue and groove structure 320, so that the pole structure 300 can be easily disassembled, thereby allowing maintenance and replacement of the battery cell.
[0065] Figure 5 for Figure 3 A partial enlarged view of the D area in the middle. Please refer to Figure 5 An elastic portion 330 is provided in the mortise and tenon structure 320 , and the elastic portion 330 is fixed within the mortise and tenon structure 320 . The flange portion 312 can be stuck within the elastic portion 330 to form a detachable connection with the elastic portion 330 .
[0066] Through the above solution, the elastic portion 330 is provided within the tongue-and-groove structure 320, so that the flange portion 312 can be stuck within the elastic portion 330, forming a detachable connection. In addition, the outer periphery of the side wall 322 of the tongue-and-groove structure 320 forms a sealed connection with the top cover body 100. This allows the tongue-and-groove structure 320 to achieve a sealing effect with the top cover while also achieving a detachable connection with the flange portion 312. This design makes the top cover as a whole strong and reliable, while also having a certain degree of flexibility and detachability, facilitating maintenance and replacement.
[0067] Please continue to refer to Figure 5 In this embodiment, the elastic portion 330 includes a bottom base plate 331, a movable waist plate 332, and a clamping plate 333. The movable waist plate 332 is fixedly arranged along the outer periphery of the bottom base plate 331 to form a mortise. The shape of the mortise matches the shape of the flange portion 312. The flange portion 312 has an insertion end and a clamping end away from the insertion end. The cross-sectional diameter of the flange portion 312 gradually increases from the clamping end to the insertion end. The cross-sectional diameter of the mortise gradually increases from the entrance of the mortise to the bottom base plate 331. The flange portion 312 is inserted into the mortise along the entrance of the mortise toward the bottom base plate 331. When the flange portion 312 is inserted into the mortise, the clamping end of the mortise is clamped by the entrance of the mortise.
[0068] Through the above solution, the flange portion 312 has an insertion end and a snap-on end. The insertion end is used to insert into the mortise, while the snap-on end is used to form a snap connection with the snap-on plate 333 of the mortise. The cross-sectional diameter of the mortise gradually increases from the entrance to the bottom substrate 331, matching the change in the cross-sectional diameter of the flange portion 312, so that the flange portion 312 can gradually "lock" into the mortise when inserted into the mortise. This self-locking mechanism ensures the stability of the connection and prevents the flange portion 312 from accidentally falling off due to vibration or impact. The flange portion 312 is inserted into the bottom substrate 331 along the entrance of the mortise. When the flange portion 312 is inserted into the mortise, the snap-on end of the mortise is caught by the entrance of the mortise, achieving snap connection. This snap-on connection method provides a secure connection while allowing the flange portion 312 to be disassembled through appropriate operations when necessary.
[0069] Please refer to Figure 5 In this embodiment, the insertion end is provided with an inclined surface 313, which enables the flange portion 312 to be inserted from the entrance of the mortise.
[0070] Bevel 313 is a slanted surface at the insertion end of flange 312 that helps reduce friction during insertion, making it easier for flange 312 to fit into the mortise. With this approach, when flange 312 is inserted into the mortise, bevel 313 first contacts the mortise's sidewall 322. Due to the design of bevel 313, this reduces the force required for insertion, making the entire insertion process smoother. The presence of bevel 313 also helps guide flange 312 into proper alignment with the mortise, reducing the risk of misalignment or jamming. Even though the cross-sectional diameter of flange 312 gradually increases from the engaging end to the insertion end, the design of bevel 313 allows for easy initial insertion of flange 312. Once past bevel 313, the increased diameter of flange 312 causes it to lock into the mortise, achieving self-locking. The design of bevel 313 at the insertion end balances ease of insertion with connection stability.
[0071] Figure 6 Schematic diagram of the elastic portion 330 provided in one embodiment of the present application. Figure 7 for Figure 6 The cross-sectional view of the elastic portion 330 along the B-B1 direction is provided in FIG. Figure 5 、 Figure 6 and Figure 7 The clamping plate 333 is fixed at the entrance of the mortise, the clamping plate 333 is fixed on the outside of the mortise and extends toward the direction of the mortise structure 320.
[0072] With the above arrangement, the clamping plate 333 is fixed to the outside of the mortise and extends toward the mortise structure 320. In this design, when the flange 312 is inserted into the mortise, its clamping end contacts and becomes locked in place by the clamping plate 333. Because the clamping plate 333 extends toward the mortise structure 320, it forms a barrier outside the mortise, preventing the flange 312 from slipping out of the mortise. The clamping plate 333 provides additional support outside the mortise, enhancing the stability of the connection.
[0073] Figure 8 This is a schematic diagram of an elastic portion 330 provided in another embodiment of the present application. Figure 9 for Figure 8 The cross-sectional view of the elastic portion 330 along the C-C1 direction is provided in FIG. Figure 8 and Figure 9 The clamping plate 333 is fixed on the inner side of the mortise and extends in a direction away from the mortise and tenon structure 320 .
[0074] The clamping plate 333 is fixed to the inside of the mortise and extends away from the mortise structure 320. In this design, the clamping end of the flange portion 312 is captured by the clamping plate 333 after being inserted into the mortise. The clamping plate 333 forms a reverse barrier inside the mortise, preventing the flange portion 312 from easily dislodging from the mortise. The design of the clamping plate 333 inside the mortise makes the overall structure more compact, reduces external protrusions, and is more suitable for applications with limited space.
[0075] The two aforementioned methods for securing the clip plate 333 each have their advantages, and the choice depends on specific application requirements and design considerations. The first method may be more suitable for scenarios requiring higher stability and ease of operation, while the second method may be more suitable for applications with limited space or requiring a concealed clip mechanism. The appropriate method for securing the clip plate 333 can be selected based on factors such as the specific battery cell's usage environment, maintenance requirements, and manufacturing costs.
[0076] Please refer to Figure 6 and Figure 8 The movable waist plate 332 can be composed of a plurality of dispersed plates, which surround a circle to form the main body of the mortise. In this way, when the flange 312 is inserted, the plurality of dispersed plates can automatically adjust according to the shape of the flange 312 to form a mortise with an elastic effect. Figure 6 and Figure 8 The movable waist plate 332 is composed of four dispersed plates.
[0077] In one embodiment, a conductive adhesive is provided between the flange portion 312 and the movable waist plate 332. Conductive adhesive is an adhesive that has a certain conductive property after curing or drying. It is mainly composed of a base resin and a conductive filler (such as metal powder). The conductive particles are combined together by the bonding effect of the base resin to form a conductive path, thereby achieving a conductive connection of the bonded materials. Conductive adhesive can provide a stable conductive connection. Its conductive mechanism is mainly the mutual contact between the conductive particles to form an electrical path. After curing or drying, the volume of the adhesive shrinks due to the volatilization of the solvent and the curing of the adhesive, so that the conductive particles are in stable and continuous contact with each other, thus showing conductivity. By providing a conductive adhesive between the flange portion 312 and the movable waist plate 332, not only a stable conductive connection can be achieved, but also good mechanical bonding performance can be provided.
[0078] Please refer to Figure 4 In this embodiment, the top cover also includes an upper plastic 110, a lower plastic 120 and a sealing ring 150; the upper plastic 110 is provided above the outer periphery of the side wall 322 of the tenon portion, and the lower plastic 120 is provided below the outer periphery of the side wall 322 of the tenon portion, and the sealing ring 150 is arranged between the upper plastic 110 and the lower plastic 120.
[0079] By disposing the upper plastic 110 above the outer periphery of the side wall 322 of the tongue and groove portion and ensuring that it is electrically connected to the positive electrode post and insulated from the negative electrode post, accidental short circuits can be prevented during battery use, thereby improving the safety of the battery. The lower plastic 120 can be laid flat below the top cover body 100, forming an insulated connection with the pole structure 300, which helps to rationally distribute and manage heat inside the battery, prevent local overheating, and reduce the risk of thermal runaway of the battery. The tongue and groove portion passes through the lower plastic 120, and the bottom plate 321 is electrically connected to the connecting piece 210 by welding. The use of the upper and lower plastics 120 can enhance the connection strength between the pole and the top cover, and improve the structural stability of the entire battery top cover.
[0080] The design of the sealing structure must take into account the sealing requirements of the battery cell in different operating environments, including factors such as temperature fluctuations, pressure changes, and chemical corrosion. A sealing ring 150 is provided between the upper plastic 110 and the lower plastic 120. This effectively prevents the exchange of substances between the interior of the housing cavity where the bare battery cell 201 is located and the external environment, preventing moisture, dust, and other substances from entering the battery interior, thereby improving the battery's protection level.
[0081] Through the above solution, the upper plastic 110, the lower plastic 120 and the sealing ring 150 together constitute the sealing structure of the battery cell top cover, which can effectively protect the electrical components inside the battery cell and extend the service life of the battery cell.
[0082] In this embodiment, the top cover further includes an explosion-proof structure 130 and a sealing member 140 , and the explosion-proof structure 130 and the sealing member 140 are disposed on the top cover body 100 .
[0083] Through the above solution, the explosion-proof structure 130 is an important part of the battery safety design. When the pressure inside the battery increases due to abnormal conditions, the explosion-proof structure 130 can be opened in time to release the internal pressure and prevent the battery from exploding, thereby protecting the safety of the battery and the surrounding environment. The injection hole is a channel for injecting electrolyte during the battery manufacturing process. After the injection is completed, it is necessary to ensure the sealing of the injection hole to prevent electrolyte leakage and the intrusion of external contaminants. The design of the seal 140 can prevent the generation of metal particles and burrs, which may fall into the interior of the battery and cause a short circuit. The use of the seal 140 can ensure the cleanliness of the interior of the battery and improve the reliability and safety of the battery.
[0084] Based on the lithium-ion battery cell mentioned above, this embodiment further provides a power battery, including a busbar and any one of the lithium-ion battery cells mentioned above, wherein the lithium-ion battery cell is connected to the busbar.
[0085] Since the structure and beneficial effects of the lithium-ion battery cell have been described in detail in the previous embodiments, they will not be repeated here in this application.
[0086] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.
Claims
1. A lithium-ion battery cell, characterized in that: include: A bare cell, a top cover, and a shell, wherein the top cover and the shell together form a receiving cavity, and the bare cell is located in the receiving cavity; The top cover comprises a top cover body, and a pole structure is provided on the top cover body; The pole structure includes a tenon portion and a tenon groove structure. The tenon groove structure is arranged through the top cover body. The tenon portion cooperates with the tenon groove structure to form a detachable connection.
2. The lithium-ion battery cell according to claim 1, characterized in that The tenon portion includes a welding portion and a flange portion connected to the welding portion. The welding portion can form a welding connection with the external busbar, and the flange portion can cooperate and extend into the interior of the tenon-groove structure to form a detachable connection.
3. The lithium-ion battery cell according to claim 2, characterized in that The tongue and groove structure includes an elastic portion, which is fixedly arranged in the tongue and groove structure. The flange portion can be clamped in the elastic portion to form a detachable connection with the elastic portion.
4. The lithium-ion battery cell according to claim 3, characterized in that The elastic portion includes a bottom base plate, a movable waist plate and a clamping plate, wherein the movable waist plate is fixedly arranged along the outer periphery of the bottom base plate to form a mortise, and the shape of the mortise matches the shape of the flange portion; The flange portion has an insertion end and a clamping end away from the insertion end, and the cross-sectional diameter of the flange portion gradually increases along the direction from the clamping end to the insertion end; The cross-sectional diameter of the mortise gradually increases along the direction from the entrance of the mortise to the bottom substrate; The flange portion is inserted into the direction of the bottom substrate along the entrance of the mortise. When the flange portion is inserted into the mortise, the clamping end of the mortise is clamped by the entrance of the mortise.
5. The lithium-ion battery cell according to claim 4, characterized in that: The insertion end is provided with an inclined surface, and the inclined surface enables the flange portion to be inserted from the entrance of the mortise.
6. The lithium-ion battery cell according to claim 4, characterized in that The clipping plate is fixed at the entrance of the mortise, the clipping plate is fixed on the outside of the mortise and extends toward the direction of the mortise structure, or the clipping plate is fixed on the inside of the mortise and extends away from the mortise structure.
7. The lithium-ion battery cell according to claim 4, characterized in that Conductive adhesive is provided between the flange portion and the movable waist plate.
8. The lithium-ion battery cell according to claim 1, characterized in that The pole structure includes a positive pole structure for electrically connecting to the positive pole piece on the bare battery cell and a negative pole structure for electrically connecting to the negative pole piece on the bare battery cell; the tongue and groove structure includes a bottom plate and a side wall, the bottom plate can be connected to the positive pole piece or the negative pole piece on the bare battery cell, and the outer periphery of the side wall forms a sealed connection with the top cover body.
9. The lithium-ion battery cell according to claim 1, characterized in that The top cover also includes an upper plastic, a lower plastic, a sealing ring, an explosion-proof structure and a sealing member. The upper plastic is provided above the outer periphery of the side wall of the tenon groove portion, and the lower plastic is provided below the outer periphery of the side wall of the tenon groove portion. The sealing ring is provided between the upper plastic and the lower plastic; the explosion-proof structure and the sealing member are provided on the top cover body.
10. A power battery, characterized in that: The invention comprises a busbar and a lithium-ion battery cell according to any one of claims 1 to 9, wherein the tenon portion can be connected to the busbar so that the lithium-ion battery cell is connected to the busbar.