Cover assembly and battery cell
By setting a raised insulating part on the terminal post assembly, the riveting head is ensured not to contact the insulating part, thus solving the problem of insulation damage during the riveting process of traditional square battery cover assemblies, achieving the effects of insulation reliability and simplified assembly.
Patent Information
- Application Number
- CN202522332915.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-03
- Publication Date
- 2026-11-06
- Estimated Expiration
- 2035-11-03
AI Technical Summary
During the riveting process, the insulation part of traditional square battery cover assemblies is easily squeezed, scratched or cracked by the riveting head, resulting in a decrease in insulation performance, posing safety hazards, and also increasing assembly complexity and cost.
A cover plate assembly was designed. By setting a raised insulating part on the pole post assembly, a height difference exists between the first limiting part and the insulating part, which avoids the riveting head from contacting the insulating part. Combined with the encapsulation process, an integrated insulating structure is formed, which simplifies assembly and improves insulation reliability.
This effectively avoids damage to the insulation, improves battery safety and reliability, simplifies the assembly process, and reduces the number of parts and costs.
Smart Images
Figure CN224946849U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to a cover plate assembly and a battery cell. Background Technology
[0002] Currently, batteries are mainly divided into cylindrical batteries and prismatic batteries. The casing of a prismatic battery includes a housing and a cover plate assembly. The housing provides a sealed space to house the electrode assembly and electrolyte, while the electrode assembly extends from this sealed space to the outside through the cover plate. Since the cover plate is typically made of metal and is conductive, upper and lower plastic inserts are needed between the electrode assembly and the cover plate for insulation. These upper and lower plastic inserts undoubtedly increase the number of parts and the assembly complexity of the cover plate assembly. Utility Model Content
[0003] This application proposes a cover plate assembly and a battery cell, aiming to provide a cover plate assembly that can avoid the riveting mechanism and prevent the insulation part from being crushed by the riveting mechanism during the assembly process.
[0004] An embodiment of this application provides a cover plate assembly including a cover plate body, a first limiting part, a pole post assembly, and an insulating part. The pole post assembly includes a pole post body and a second limiting part. The pole post body passes through a first through hole in the cover plate body and overlaps with a first surface of the cover plate body through the second limiting part. The insulating part overlaps with the second limiting part. The first limiting part is disposed on the first surface. The first limiting part overlaps with the insulating part to limit the insulating part and the second limiting part. The maximum straight-line distance from the first limiting part to the first surface is greater than or equal to the maximum distance from the insulating part to the first surface.
[0005] In one embodiment, the insulating portion further includes a protrusion located between the pole body and the flange, the protrusion having a first plane facing away from the second limiting portion; The first limiting part includes a flange and a connecting segment connected together, the flange and the connecting segment are arranged at an angle, the flange overlaps the second limiting part, and the flange has a second plane facing away from the second limiting part; The maximum distance from the first plane to the first surface is greater than the maximum distance from the second plane to the first surface.
[0006] In one embodiment, the protrusion has an inner peripheral wall and an outer peripheral wall disposed opposite to each other, the inner peripheral wall and the outer peripheral wall being connected by a first plane, the first plane being inclined toward the flange.
[0007] In one embodiment, the inner peripheral wall abuts against the pole body, the outer peripheral wall is disposed toward the flange, and the first plane and the outer peripheral wall are transitioned by an arc surface.
[0008] In one embodiment, the first plane has an avoidance notch on the side near the flange.
[0009] In one embodiment, the minimum distance between the first plane and the second plane along the direction perpendicular to the main body of the cover plate is 0.05 mm to 0.5 mm.
[0010] In one embodiment, the second limiting part has an upper flange surface and a lower flange surface disposed opposite to each other, and an intermediate surface is provided between the upper flange surface and the lower flange surface; The insulating part further includes a first insulating part, a second insulating part, and a third insulating part connected in sequence. The first insulating part abuts against the upper flange surface, the third insulating part abuts against the lower flange surface, and the second insulating part abuts against the intermediate surface. The protrusion is provided on the side of the first insulating part facing away from the upper flange surface.
[0011] In one embodiment, the first limiting portion further includes an extension section, which is disposed on the cover plate body and surrounds the first through hole, and the flange is disposed at the end of the extension section away from the cover plate body; The flange, the extension section, and the cover plate body together form a snap-fit groove with an opening facing the first through hole, and at least a portion of the insulating part is snapped into the snap-fit groove.
[0012] In one embodiment, the cover plate assembly further includes a sealing ring, the sealing ring including a first sealing portion and a second sealing portion connected to each other, the first sealing portion sealingly abutting against the cover plate body and the second limiting portion respectively; the second sealing portion sealingly abutting against the cover plate body and the pole body respectively.
[0013] An embodiment of this application also provides a battery cell, the battery cell including a housing, an electrode assembly and a cover assembly as described above, the electrode assembly being disposed inside the housing and the cover assembly covering the opening of the housing.
[0014] This application ensures that the maximum straight-line distance from the first limiting part to the first surface of the cover plate body is greater than or equal to the maximum distance from the insulating part to the first surface of the cover plate body. This ensures that the highest point of the insulating part is lower than the first limiting part in the height direction, thereby preventing the riveting head used for flanging from damaging the insulating part during the flanging process of the first limiting part. Specifically, the cover plate assembly includes a cover plate body, a first limiting part, a pole assembly, and an insulating part. The pole body of the pole assembly passes through a first through hole in the cover plate body and overlaps with the first surface of the cover plate body through the second limiting part. The insulating part covers the pole assembly to prevent the cover plate body from contacting the pole assembly and causing a short circuit. The insulating part overlaps with the second limiting part. The first limiting part can be folded towards the pole assembly to overlap and lock the second limiting part for fixation. Since the contact surface of the riveting head of the riveting mechanism is always flush with the plane furthest from the first limit part, it can be ensured that the contact surface of the riveting mechanism will not come into contact with the insulating part when it is pressed down. The height difference between the highest point of the insulating part and the first limit part effectively avoids the contact surface of the riveting mechanism, thereby preventing the insulating part from being squeezed, deformed or cracked, thus ensuring the insulation reliability of the terminal assembly and improving the safety of the battery. Attached Figure Description
[0015] 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.
[0016] Figure 1 A cross-sectional structural schematic diagram of an embodiment of the cover plate assembly provided in this application; Figure 2 for Figure 1 A magnified view of a portion of the middle insulation section; Figure 3 This is a schematic diagram showing the positions of heights H1 and H2; Figure 4 A schematic diagram of the structure of the first embodiment of the insulating part provided in this application; Figure 5 A schematic diagram of the structure of the second embodiment of the insulating part provided in this application; Figure 6 A schematic diagram of the structure of the third embodiment of the insulating part provided in this application; Figure 7 An exploded view of an embodiment of the cover plate assembly provided in this application; Figure 8 This is an assembly diagram of the cover plate assembly proposed in this application; Figure 9This is a schematic diagram of the structure of one embodiment of the battery cell proposed in this application.
[0017] Explanation of icon numbers: 100. Cover plate assembly; 1. Cover plate body; 1a. First through hole; 1b. First surface; 1c. Injection hole; 1d. Snap-fit groove; 11. First limiting part; 111. Flanged edge; 111a. Second plane; 112. Extension section; 12. Explosion-proof valve; 2. Pole post assembly; 21. Pole post body; 22. Second limiting part; 23. Pole post extension; 22a. Upper flange face; 22b. Lower flange face; 22c. Middle surface; 3. Insulating part; 31. First insulating part; 32. Second insulating part; 33. Third insulating part; 3a. Insulating top surface; 4. Protrusion; 4a. First plane; 4b. Arc surface; 4c. Clearance notch; 4d. Inner peripheral wall; 4e. Outer peripheral wall; 5. Sealing ring; 51. First sealing part; 52. Second sealing part; 6. Lower plastic.
[0018] 200, housing; 200a, accommodating cavity; 300, electrode assembly; 400, adapter plate. Detailed Implementation
[0019] 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.
[0020] It should be noted that if multiple embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators 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 indicators will also change accordingly.
[0021] 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.
[0022] Currently, in traditional square battery cover designs, the cover body 1 is typically made of metal (such as aluminum alloy or stainless steel) due to its good mechanical strength and processing performance. However, metal materials are inherently conductive, and to prevent short circuits between the terminals and the cover body, an insulating structure must be installed between them. The traditional method involves using two separate insulating parts—an upper plastic and a lower plastic—between the terminals and the cover to achieve electrical isolation. While this design meets basic insulation requirements, it also introduces several problems: firstly, it increases the number of parts in the cover assembly, making the overall structure more complex; secondly, it requires precise alignment and fixation during assembly, increasing assembly steps and difficulty, reducing production efficiency, and also increasing costs.
[0023] To address the aforementioned issues, novel coated terminal block structures have been gradually introduced into battery cover designs. The core idea of this structure is to integrate insulation functionality. Through a coating process (such as injection molding or insert molding), a layer of insulating material (such as PPS, PPA, LCP, or other high-performance engineering plastics) is directly coated onto the outside of the terminal block, forming an integrated insulating layer. This coated terminal block structure not only simplifies the number of components but also improves the sealing and insulation reliability between the terminal block and the cover plate. During assembly, the coated terminal block structure directly contacts the cover plate body 1 through its external insulating layer 3, thereby achieving electrical isolation between the terminal block and the cover plate. This eliminates the need for additional upper and lower plastic components, greatly simplifying the assembly process.
[0024] However, in order to achieve a reliable connection and fixation between the rubber-coated electrode structure and the cover plate body 1, the cover plate body 1 usually has a thin-walled first limiting part 11 around the first through hole 1a (for leading out the electrode body 21). After the rubber-coated electrode structure is inserted into the lead-out hole and positioned, the first limiting part 11 needs to be riveted using a riveting device to cause plastic deformation, forming an inwardly folded flange 111 structure. This flange 111 can be tightly fastened to the insulating part 3 of the rubber-coated electrode structure, thereby achieving axial fixation of the electrode assembly 2 on the cover plate body 1 and preventing it from loosening or falling off during use. Although this riveting connection method performs well in terms of structural strength, it exposes a serious defect in actual production: because the first limiting part 11 is located at the edge of the electrode lead-out hole, its thickness is usually thin, and the riveting mechanism is difficult to achieve completely uniform and precise control during the application of force. During the riveting process, the riveting head is highly susceptible to causing localized compression, scratches, or even cracking of the insulation portion 3 on the outside of the rubber-coated terminal structure. Once the insulation portion 3 is damaged, its insulation performance will decrease significantly, potentially leading to micro-short circuits or leakage between the terminal and the cover plate. In severe cases, this could even cause battery thermal runaway, fire, or other safety accidents. Furthermore, damage to the insulation portion 3 is often insidious and difficult to detect in routine inspections, posing a significant threat to the long-term reliability of the battery.
[0025] To address the aforementioned problems, this application proposes a cover plate assembly 100 to solve the technical issues mentioned above.
[0026] Please see Figure 1 In one embodiment of this application, the cover plate assembly 100 includes a cover plate body 1, a first limiting part 11, a pole post assembly 2, and an insulating part 3. The pole post assembly 2 includes a pole post body 21 and a second limiting part 22. The pole post body 21 passes through a first through hole 1a opened on the cover plate body 1 and overlaps with the first surface 1b of the cover plate body 1 through the second limiting part 22. The insulating part 3 overlaps with the second limiting part 22. The first limiting part 11 is disposed on the first surface 1b. The first limiting part 11 overlaps with the insulating part 3 to limit the insulating part 3 and the second limiting part 22. The maximum straight-line distance from the first limiting part 11 to the first surface 1b is greater than or equal to the maximum distance from the insulating part 3 to the first surface 1b.
[0027] It is understandable that the maximum straight-line distance from the first limiting part 11 to the first surface 1b, that is, the distance between the top surface of the portion of the first limiting part 11 that overlaps the insulating part 3 and the first surface 1b along the direction perpendicular to the cover plate body 1, please refer to [reference needed]. Figure 3 , that is Figure 3 H1; the maximum distance from the insulating part 3 to the first surface 1b, that is, the distance between the highest point of the insulating part 3 along the direction perpendicular to the cover plate body 1 and the projection of the highest point of the insulating part 3 onto the first surface 1b, that is... Figure 3H2. H1≥H2, thereby ensuring that the first plane 4a of the protrusion 4 on the insulating part 3 and the second plane 111a of the flange 111 have a height difference, thereby avoiding the riveting head of the riveting mechanism from contacting the protrusion 4 and causing it to be crushed.
[0028] When H1 = H2, the first plane 4a of the protrusion 4 on the insulating part 3 is inclined, and the highest point of the first plane 4a is at the same horizontal plane as the second plane 111a of the flange 111. The inclined first plane 4a can effectively avoid the riveting head, thereby preventing it from contacting the insulating part 3. When H1 > H2, the first plane 4a of the protrusion 4 on the insulating part 3 can be horizontal or inclined, and this application does not impose any restrictions. The height difference design between the first plane 4a and the second plane 111a ensures that the riveting head only contacts the second plane 111a of the flange 111, while the first plane 4a of the protrusion 4 is lower than this plane, thereby effectively avoiding the insulating part 3, preventing it from being squeezed, deformed or cracked, ensuring that the insulation performance of the terminal post is not damaged, and improving the safety and reliability of the battery. The protrusion 4 is the highest point of the insulating part 3 along the direction perpendicular to the cover body 1. If it can be ensured that the protrusion 4 does not contact the riveting head, the structural integrity of the insulating part 3 can be guaranteed.
[0029] To secure the terminal assembly 2, a second limiting part 22 is provided on the outer peripheral wall 4e of the terminal body 21. The terminal body 21 and the second limiting part 22 are integrally formed. The terminal assembly 2 overlaps the cover body 1 on the side facing away from the battery interior via the second limiting part 22. The insulating part 3 is fitted onto the outside of the second limiting part 22 through an encapsulation process, thereby isolating the second limiting part 22 from the cover body 1 and preventing direct contact that could lead to a short circuit. The insulating part 3 is processed through an encapsulation process, forming a whole with the terminal assembly 2. This eliminates the need for later assembly alignment and removes the risk of insulation failure due to loosening, misalignment, or vibration. It also reduces the number of parts and assembly tolerances, making the electrical isolation between the terminal and the cover more reliable, the sealing more complete, and the overall structure more compact. The first limiting part 11 on the cover plate body 1 is disposed around the first through hole 1a and is bent inward to form a flange 111. The flange 111 is directly engaged with the insulating part 3, thereby reliably fixing the insulating part 3 to the cover plate body 1.
[0030] This application reduces the distance between the first plane 4a of the protrusion 4 (i.e., the upper top surface of the protrusion 4) and the upper top surface of the insulating part 3, or increases the distance between the second plane 111a of the flange 111 (i.e., the upper top surface of the flange 111) and the upper top surface of the insulating part 3, so that the first plane 4a and the second plane 111a have a certain height difference, ensuring that the first plane 4a is lower than the second plane 111a in the height direction, thereby avoiding damage to the insulating part 3 during the flange 111 process. Specifically, the cover plate assembly 100 includes a cover plate body 1, a pole assembly 2, and an insulating part 3. The pole assembly 2 is designed to penetrate the first through hole 1a on the cover plate body 1. The insulating part 3 covers the pole assembly 2 to prevent the cover plate body 1 from contacting the pole assembly 2 and causing a short circuit. The cover plate body 1 is provided with a first limiting part 11 on the circumferential side of the first through hole 1a. The first limiting part 11 has a flange 111 that can be folded toward the pole assembly 2 to clamp the pole assembly 2 for fixation. The flange 111 is also the part of the upper end of the first limiting part 11 that is squeezed and deformed by the riveting mechanism. The contact surface between the riveting mechanism and the flange 111 is also the first plane 4a of the flange 111. The second plane 111a of the protrusion 4 is lower than the first plane 4a. Since the contact surface of the riveting mechanism is always flush with the first plane 4a, it can be ensured that the contact surface of the riveting mechanism will not come into contact with the second plane 111a when it is pressed down. The height difference between the first plane 4a and the second plane 111a effectively avoids the contact surface of the riveting mechanism, thereby preventing the protrusion 4 on the insulating part 3 from being squeezed, deformed or cracked, thus ensuring the insulation reliability of the pole assembly 2 and improving the safety of the battery.
[0031] When the riveting mechanism rivets the first limiting part 11, its upper end deforms to form a flange 111. The flange 111, the extension 112 (i.e., the undeformed part of the first limiting part 11), and the cover plate body 1 together form an annular snap-fit groove 1d that connects to the first through hole 1a. For details, please refer to further reading. Figure 2 The locking groove 1d is located on the circumferential side of the first through hole 1a, and the pole body 21 of the pole assembly 2 is disposed through the first through hole 1a. The second limiting part 22 is precisely confined within the locking groove 1d. The locking groove 1d and the second limiting part 22 cooperate to restrict the degree of freedom of movement of the pole assembly 2 in the direction perpendicular to the cover plate body 1, thereby preventing the pole assembly 2 from detaching from the cover plate body 1.
[0032] Furthermore, after the flange 111 is folded into place, the side of the flange 111 facing the insulating part 3, that is, the side facing away from the second plane 111a, will be in close contact with the top surface 3a of the insulation. Therefore, it is only necessary to ensure that the thickness of the flange 111 is greater than the height of the protrusion 4 to avoid damage to the insulating part 3. It should be noted that, in order to create a height difference between the first plane 4a and the second plane 111a, the overall height of the protrusion 4 can be designed to be smaller, or the overall thickness of the first limiting part 11 can be designed to be larger, thereby increasing the thickness of the flange 111. This application does not impose any restrictions on this.
[0033] In the above embodiments, there is always a height difference between the first plane 4a and the second plane 111a along the direction perpendicular to the cover plate body 1. This application does not limit the specific shape or structure of the first plane 4a, only requiring that the highest point of the first plane 4a be lower than the second plane 111a, to ensure that the riveting head of the riveting mechanism will not contact the first plane 4a, thereby ensuring the integrity of the insulating part 3. This application proposes three structures for the insulating part 3. The overall structure of these three insulating parts 3 is basically the same. The insulating part 3 includes a first insulating part 31, a second insulating part 32, and a third insulating part 33 connected in sequence. The first insulating part 31 abuts against the upper flange surface 22a, the third insulating part 33 abuts against the lower flange surface 22b, and the second insulating part 32 abuts against the middle surface 22c. However, the shape of the first plane 4a of the three insulating parts 3 is different to adapt to different assembly requirements.
[0034] First Embodiment Please see Figure 4 In the first embodiment of this application, the first plane 4a is horizontal. Designing the first plane 4a as horizontal makes it the simplest to process and the easiest to control in terms of size. As long as its overall height is lower than that of the second plane 111a, it can steadily avoid the riveting head without the need for additional chamfering or surface calculations. This reduces mold costs and increases yield, while providing the maximum clearance for the riveting process and completely eliminating the risk of the insulation part 3 being crushed.
[0035] Second Embodiment Please see Figure 5In the second embodiment of this application, to further ensure that the riveting mechanism does not come into contact with the insulating part 3 during the pressing process, thus preventing damage to the insulating part 3, the first plane 4a of the protrusion 4 is inclined and tilted towards the side of the flange 111. That is, the angle between the first plane 4a and the cross-section of the inner peripheral wall 4d of the protrusion 4 is an acute angle, and the angle between the first plane 4a and the cross-section of the outer peripheral wall 4e of the protrusion 4 is an obtuse angle. After the first plane 4a is inclined, a slope with a higher inner side and a lower outer side is formed. Even if the riveting head is over-pressurized, it can only slide along the slope to dissipate the force and will not vertically impact the insulating part 3. The acute angle side is close to the pole, which not only retains sufficient wall thickness to ensure strength, but also provides more clearance space, completely eliminating the risk of cracking. At the same time, the slope is conducive to injection molding demolding, reduces burrs, and improves yield and assembly safety. In addition, the first plane 4a can also be an arc-shaped slope, which is not limited in this application.
[0036] Third Embodiment Please see Figure 6 In the third embodiment of this application, the first plane 4a of the protrusion 4 is provided with a clearance notch 4c, which can form a height difference with the second plane 111a. By directly excavating the clearance notch 4c in the first plane 4a, a local depression can be formed without modifying the flange 111 or reducing the overall height. This ensures a safe height difference with the second plane 111a and minimizes the thickness of the stress area of the insulating part 3, so that even if the riveting head deviates, it will only hit the flange 111 and float over the notch, completely avoiding the compression of the insulating part 3. In addition, the notch also saves material, reduces weight, improves injection molding flow, and reduces shrinkage marks and internal stress.
[0037] In addition to the three embodiments described above, in another embodiment of this application, the first plane 4a and the outer peripheral wall 4e of the protrusion 4 are transitioned by an arc surface 4b. For details, please refer to further reading. Figure 2 The rounded corner design here transforms the sharp corners of the first plane 4a and the outer peripheral wall 4e into smooth curved surfaces, further creating a clearance area. Even if the tooling shifts slightly during riveting, the pressure will be dispersed and unloaded along the tangent of the arc, avoiding stress concentration. Simultaneously, the rounded corners facilitate melt flow, resulting in injection molding without stagnation or weld lines, and smooth demolding. This improves both strength and appearance yield, achieving the dual advantages of impact resistance and ease of molding. The rounded corner design proposed in this embodiment can be combined with the three embodiments described above to obtain three new implementation methods. In these three new combined embodiments, both clearance for the riveting head and avoidance of stress concentration in the protrusion 4 structure can be considered.
[0038] In one embodiment of this application, the distance between the first plane 4a and the second plane 111a is 0.05mm to 0.5mm. When the cover plate body 1 is thin, the riveting stroke is short, or the tooling positioning accuracy is high, a small distance of 0.05-0.1mm is used, which is sufficient to avoid collisions without affecting the fastening strength of the flange 111. When the cover plate body 1 is thick, the riveting amount is large, the tooling is subject to vibration or thermal expansion, or additional safety margin is required, a larger distance of 0.3-0.5mm is selected to absorb errors and rebound, ensuring that the riveting head will not touch the insulating part 3 under any extreme working conditions. Generally speaking, the distance between the first plane 4a and the second plane 111a is preferably 0.2mm. 0.2mm is in the middle of the range, balancing collision avoidance and structural strength. It provides a safety margin of twice the minimum value to accommodate common tooling deviations, plate thickness tolerances, and riveting springback; it is also much smaller than the upper limit to avoid loosening of the fastening or insufficient compression of the sealing ring 5 due to excessively high flange 111. At the same time, it saves materials and reduces the total height of the cover plate, achieving the optimal balance between safety, reliability, and energy density.
[0039] To facilitate the connection between the terminal post and the external busbar, the terminal post assembly 2 also includes a terminal post extension 23. For details, please refer to [link to relevant documentation]. Figure 2 The pole extension 23 is located on the circumferential side of the pole body 21 and is connected to the upper flange surface 22a. The upper top surface of the pole extension 23 is coplanar with the side of the first plane 4a further away from the second limiting part 22. The pole extension 23 raises the pole body 21 and makes it flush with the first plane 4a, forming a natural welding platform, eliminating the need for an additional adapter piece 400, and ensuring that the bottom surface of the busbar does not interfere with the insulation part 3 during installation. This results in simple positioning, a large welding area, and low resistance. At the same time, the extension is integrally formed with the insulation part 3 during encapsulation, eliminating the need for secondary assembly and improving connection reliability and automation efficiency.
[0040] To ensure battery sealing and prevent moisture and dust from entering the casing through the gap between the terminal and the first through hole 1a, thus affecting battery safety, this cover assembly 100 is also equipped with a sealing ring 5. For details, please refer to... Figure 1 To adapt to the special pole assembly 2 structure proposed in this solution, the sealing ring 5 includes a first sealing part 51 and a second sealing part 52 connected to each other. The first sealing part 51 seals against the cover plate body 1 and the second limiting part 22 respectively; the second sealing part 52 seals against the cover plate body 1 and the pole body 21 respectively. The double-lip sealing ring 5 is injection molded in one piece. The first sealing part 51 cooperates with the second limiting part 22 to achieve a primary seal, and the second sealing part 52 cooperates with the pole body 21 to achieve a secondary seal. A single part forms a compression seal at the interfaces of two different diameters simultaneously, blocking any path for moisture and dust to enter the first through hole 1a. It is pre-positioned coaxially with the rubber-coated insulation part 3, and assembly does not require additional grooves or glue, which saves axial height and reduces the number of parts and the risk of missing parts.
[0041] A lower plastic piece 6 is also provided on the side of the cover body 1 facing the inside of the battery. For details, please refer to further details. Figure 1 The lower plastic 6 separates the cover body 1 from the electrode assembly 300, preventing the tabs and current collectors from directly contacting the cover and preventing internal short circuits. It is also resistant to electrolyte corrosion and absorbs assembly tolerances and vibrations, allowing the battery cell and cover to fit flexibly, improving safety and cycle life. To ensure battery safety, the cover body 1 is equipped with an explosion-proof valve 12. When an internal short circuit, overcharging, or overheating causes a sudden increase in gas pressure, the explosion-proof valve 12 immediately and precisely ruptures at the set pressure, rapidly releasing gas and preventing the casing from exploding. After venting, the battery is de-energized, and the chemical reaction terminates.
[0042] This application also proposes a battery cell, which includes a housing 200, an electrode assembly 300, and a cover plate assembly 100 as described above. For details, please refer to further references. Figure 9 The cover plate assembly 100 and the housing 200 enclose a receiving cavity 200a for accommodating the electrode assembly 300. The electrode assembly 300 is disposed within the receiving cavity 200a. The cover plate assembly 100 covers the opening of the housing 200. The tabs of the electrode assembly 300 are connected to the terminal post assembly 2 on the cover plate assembly 100 via an adapter piece 400. The specific structure of the cover plate assembly 100 is as described in the above embodiments. Since this battery cell 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.
[0043] 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 cover plate assembly, characterized in that, The device includes a cover plate body (1), a first limiting part (11), a pole assembly (2), and an insulating part (3). The pole assembly (2) includes a pole body (21) and a second limiting part (22). The pole body (21) passes through a first through hole (1a) opened on the cover plate body (1) and overlaps the first surface (1b) of the cover plate body (1) through the second limiting part (22). The insulating part (3) overlaps the second limiting part (22). The first limiting part (11) is disposed on the first surface (1b). The first limiting part (11) overlaps the insulating part (3) to limit the insulating part (3) and the second limiting part (22). The maximum straight-line distance from the first limiting part (11) to the first surface (1b) is greater than or equal to the maximum distance from the insulating part (3) to the first surface (1b).
2. The cover plate assembly as claimed in claim 1, characterized in that, The first limiting part (11) includes a flange (111) and a connecting segment (112) connected to each other. The flange (111) and the connecting segment (112) are arranged at an angle. The flange (111) overlaps the second limiting part (22). The flange (111) has a second plane (111a) facing away from the second limiting part (22). The insulating part (3) further includes a protrusion (4), which is located between the pole body (21) and the flange (111). The protrusion (4) has a first plane (4a) facing away from the second limiting part (22). The maximum distance from the first plane (4a) to the first surface (1b) is greater than the maximum distance from the second plane (111a) to the first surface (1b).
3. The cover plate assembly as claimed in claim 2, characterized in that, The protrusion (4) has an inner peripheral wall (4d) and an outer peripheral wall (4e) arranged opposite to each other. The inner peripheral wall (4d) and the outer peripheral wall (4e) are connected by the first plane (4a), which is inclined toward the flange (111).
4. The cover plate assembly as claimed in claim 3, characterized in that, The inner peripheral wall (4d) abuts against the pole body (21), the outer peripheral wall (4e) is disposed toward the flange (111), and the first plane (4a) and the outer peripheral wall (4e) are transitioned by an arc surface (4b).
5. The cover plate assembly as claimed in claim 3, characterized in that, The first plane (4a) has an avoidance notch (4c) on the side near the flange (111).
6. The cover plate assembly as claimed in claim 2, characterized in that, The minimum distance between the first plane (4a) and the second plane (111a) along the direction perpendicular to the cover plate body (1) is 0.05 mm to 0.5 mm.
7. The cover plate assembly as claimed in claim 2, characterized in that, The second limiting part (22) has an upper flange surface (22a) and a lower flange surface (22b) disposed opposite to each other, and an intermediate surface (22c) is provided between the upper flange surface (22a) and the lower flange surface (22b); The insulating part (3) further includes a first insulating part (31), a second insulating part (32) and a third insulating part (33) connected in sequence. The first insulating part (31) abuts against the upper flange surface (22a), the third insulating part (33) abuts against the lower flange surface (22b), and the second insulating part (32) abuts against the intermediate surface (22c). The protrusion (4) is provided on the side of the first insulating part (31) facing away from the upper flange surface (22a).
8. The cover plate assembly as claimed in claim 2, characterized in that, The first limiting part (11) further includes an extension section (112), which is disposed on the cover plate body (1) and surrounds the first through hole (1a). The flange (111) is disposed at the end of the extension section (112) away from the cover plate body (1). The flange (111), the extension section (112), and the cover plate body (1) surround and form a snap-fit groove (1d) with the opening facing the first through hole (1a), and at least a portion of the insulating part (3) is snapped into the snap-fit groove (1d).
9. The cover plate assembly as claimed in any one of claims 1 to 6, characterized in that, The cover plate assembly also includes a sealing ring (5), which includes a first sealing part (51) and a second sealing part (52) connected to each other. The first sealing part (51) is in sealing contact with the cover plate body (1) and the second limiting part (22) respectively; the second sealing part (52) is in sealing contact with the cover plate body (1) and the pole body (21) respectively.
10. A single battery cell, characterized in that, It includes a housing (200), an electrode assembly (300), and a cover assembly (100) as claimed in any one of claims 1 to 9, wherein the electrode assembly (300) is disposed within the housing (200), and the cover assembly (100) covers the opening of the housing (200).