Battery cell cover plate and battery cell

Abstract

The invention belongs to the technical field of batteries, and particularly discloses a battery cell cover plate and a battery cell, and a pole of the battery cell cover plate sequentially penetrates through a second plastic part, a cover plate body, a first plastic part and a connecting block and then is riveted with the connecting block. A supporting piece is arranged on one side, far away from the pole group, of the cover plate body and sleeves the pole column. In the first direction, the two opposite end faces of the supporting piece abut against the cover plate body and the connecting block respectively. When the cover plate body and the first plastic part are assembled, the supporting part plays a good role in guiding and positioning the first plastic part; meanwhile, in the riveting process of the pole and the connecting block, the supporting piece plays a role in protecting the first plastic piece, the first plastic piece is prevented from being pressed to crack, and the insulating property of the first plastic piece is good. Besides, when the first plastic part creeps in a high-temperature environment, the supporting part plays a supporting role between the cover plate body and the connecting block, the pole is prevented from sinking, and good sealing performance is ensured. The invention also provides a battery cell which comprises the battery cell cover plate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery cell cover plate and a battery cell. BACKGROUND

[0002] In the existing battery cell cover plate, the pole is generally fixed on the cover plate body by riveting. For example, some battery cell cover plates include a cover plate body, an upper plastic part, a lower plastic part, a pole and a riveting block, wherein the upper plastic part and the lower plastic part are respectively arranged on both sides of the cover plate body, the riveting block is arranged on the side of the upper plastic part away from the cover plate body, and the pole passes through the lower plastic part, the cover plate body, the upper plastic part and the riveting block in sequence from the side of the lower plastic part, and is riveted with the riveting block.

[0003] However, in the process of riveting the pole and the riveting block, the upper plastic part may crack due to excessive axial and radial riveting pressure, thereby causing the risk of insulation failure. Moreover, in the subsequent use process of the battery cell, such as when the battery cell is in a high temperature environment for a long time, the upper plastic part may creep after being subjected to high temperature, thereby the upper plastic part cannot well support the riveting block, and the pole sinks, the compression amount of the sealing ring provided on the pole is insufficient, and the battery cell cover plate has the problem of sealing failure. SUMMARY

[0004] The purpose of the present application is to provide a battery cell cover plate and a battery cell, wherein the battery cell cover plate is provided with a support part for supporting the connecting block, the support part hardly deforms after being subjected to high temperature, can continuously provide effective support for the connecting block, and has low risk of insulation failure and sealing failure.

[0005] To achieve the above purpose, the present application adopts the following technical solutions: On one hand, the present application provides a battery cell cover plate, which comprises: a cover plate body, wherein a first mounting hole is arranged on the cover plate body, a first limiting groove is arranged in the circumferential direction of the first mounting hole, and the first limiting groove is located on the end face of the cover plate body away from the pole group; a first plastic part, wherein the first plastic part is arranged on the side of the cover plate body away from the pole group in the first direction, and a second mounting hole is arranged on the first plastic part; a second plastic part, wherein the second plastic part is arranged on the side of the cover plate body close to the pole group in the first direction, and a third mounting hole is arranged on the second plastic part; a connecting block, wherein the connecting block is arranged on the side of the first plastic part away from the cover plate body in the first direction, a fourth mounting hole is arranged on the connecting block, and a riveting step is arranged in the circumferential direction of the fourth mounting hole; a pole, wherein the pole passes through the third mounting hole, the first mounting hole, the second mounting hole and the fourth mounting hole in sequence from the side of the pole group in the first direction, and is riveted with the riveting step; A support member annularly sleeved outside the pole post and at least partially embedded in the first limiting groove; opposite end faces of the support member in the first direction respectively abut against the bottom wall of the first limiting groove and the end face of the connecting block on the side of the cover body.

[0006] Optionally, in the second direction, the width of the support member is A, and the width of the contact surface of the support member and the bottom wall of the first limiting groove is a; The relationship between A and a satisfies: 0.35≤a / A≤0.75; The value range of A is: 1.2mm≤A≤3.5mm; The value range of a is: 0.45mm≤a≤2.5mm.

[0007] Optionally, in the first direction, the thickness of the support member is B, and the depth of the first limiting groove is b; The relationship between B and b satisfies: 0.35≤b / B≤0.7; The value range of B is: 1.0mm≤B≤2.5mm; The value range of b is: 0.4mm≤b≤1.5mm.

[0008] Optionally, the pole post comprises a plate body portion and a post body portion connected to each other, the post body portion sequentially passes through the third mounting hole, the first mounting hole, the second mounting hole and the fourth mounting hole in the first direction and is riveted with the riveting step, and the plate body portion is located on the side of the second plastic part away from the cover body.

[0009] Optionally, the post body portion comprises a first post body and a second post body, one end of the first post body in the first direction is connected with the plate body portion, the other end of the first post body in the first direction is connected with the second post body, the diameter of the second post body is smaller than that of the first post body, and a support step for supporting the connecting block is formed between the first post body and the second post body.

[0010] Optionally, the cell cover plate further comprises a sealing ring, the sealing ring comprises a first sealing portion and a second sealing portion, the first sealing portion is annularly arranged around the circumferential direction of the second sealing portion, in the first direction, opposite end faces of the first sealing portion respectively abut against the plate body portion and the cover body, and the second sealing portion is sleeved outside the post body portion and located between the outer circumferential wall of the post body portion and the inner wall of the first mounting hole.

[0011] Optionally, along the first direction, the end face of the second sealing part away from the side of the pole group is not higher than the end face of the cover plate body away from the side of the pole group; along the first direction, the height difference between the end face of the second sealing part away from the side of the pole group and the end face of the cover plate body away from the side of the pole group is h; The value range of h is 0mm≤h≤0.5mm.

[0012] Optionally, the first plastic part comprises a plastic part body and a limiting plate arranged circumferentially on the plastic part body, the limiting plate extends away from the pole group along the first direction, and the plastic part body and the limiting plate enclose a receiving groove for mounting the connecting block; Along the second direction, the width of the contact surface between the connecting block and the plastic part body is e1; The value range of e1 is 0.5mm≤e1≤8mm.

[0013] Optionally, along the third direction, the width of the contact surface between the connecting block and the plastic part body is e2; The value range of e2 is 0.5mm≤e2≤30mm.

[0014] In another aspect, the application provides an electric core comprising the electric core cover plate in any of the above-mentioned schemes.

[0015] The application has the following beneficial effects: The application provides an electric core cover plate, which comprises a second plastic part, a cover plate body, a first plastic part and a connecting block arranged in sequence, and a pole post is riveted to the connecting block after sequentially penetrating through the second plastic part, the cover plate body, the first plastic part and the connecting block. The end face of the cover plate body away from the side of the pole group is provided with a first limiting groove, and a support part is arranged at the first limiting groove, the support part is annular and is sleeved on the pole post, and the opposite end faces of the support part along the first direction abut against the bottom wall of the first limiting groove and the end face of the connecting block facing the side of the cover plate body. On the one hand, when the cover plate body and the first plastic part are assembled, the support part can play a good guiding and positioning role on the first plastic part to prevent the center of the first plastic part from deviating; on the other hand, in the process of riveting the pole post to the connecting block, the support part plays a protection role on the first plastic part to avoid the first plastic part from cracking due to excessive pressure and affecting the insulation performance of the first plastic part. In addition, when the first plastic part appears to creep in a high-temperature environment, the support part can still play a supporting role between the cover plate body and the connecting block to prevent the pole post from sinking and ensure that the sealing performance of the electric core cover plate is good.

[0016] The application further provides an electric core comprising the electric core cover plate. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is an exploded view of the electric core cover plate provided in the embodiments of the application; Figure 2 is a top view of the electric core cover plate provided in the embodiments of the application; Figure 3 is a sectional view of section I-I in Figure 2 Figure 4 is a partial enlarged view of III in Figure 3 Figure 5 is a sectional view of section II-II in Figure 2

[0018] In the drawings: 100, cover plate body; 110, first mounting hole; 120, first limiting groove; 200, first plastic piece; 210, plastic piece body; 211, second mounting hole; 220, limiting plate; 221, accommodating groove; 300, second plastic piece; 310, third mounting hole; 320, second limiting groove; 400, connecting block; 410, fourth mounting hole; 420, riveting step; 500, pole; 510, plate body part; 520, column body part; 521, first column body; 522, second column body; 5221, convex part; 5222, supporting step; 600, supporting piece; 700, sealing ring; 710, first sealing part; 720, second sealing part. DETAILED DESCRIPTION

[0019] The application will be further described below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application, and not to limit the application. In addition, it should be noted that, for the convenience of description, only the parts related to the application are shown in the drawings, not all the structures.

[0020] In the description of the application, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances. ​​​

[0021] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "over" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is higher in horizontal height than the second feature. The first feature "under", "below" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the first feature is lower in horizontal height than the second feature.

[0022] In the description of the present embodiment, the terms "upper", "lower", "left", "right", and other orientation or position relationships shown in the drawings are based on the orientation or position relationships shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used to distinguish in description and have no special meaning.

[0023] As shown in Figures 1-3 The present embodiment provides a battery cell cover plate, which comprises a cover plate body 100, a first plastic part 200, a second plastic part 300, a connecting block 400, a pole 500 and a support 600.

[0024] The first plastic part 200 is arranged on one side of the cover plate body 100 away from the pole group in a first direction, the second plastic part 300 is arranged on one side of the cover plate body 100 close to the pole group in the first direction, and the connecting block 400 is arranged on one side of the first plastic part 200 away from the cover plate body 100 in the first direction. The above-mentioned first direction is the X-axis direction shown in Figure 1 , which is also the thickness direction of the cover plate body 100. That is, the second plastic part 300, the cover plate body 100, the first plastic part 200 and the connecting block 400 are sequentially stacked in the first direction. The cover plate body 100 is provided with a first mounting hole 110, the first plastic part 200 is provided with a second mounting hole 211, the second plastic part 300 is provided with a third mounting hole 310, the connecting block 400 is provided with a fourth mounting hole 410, and the pole 500 is riveted with the connecting block 400 after sequentially passing through the third mounting hole 310 on the second plastic part 300, the first mounting hole 110 on the cover plate body 100, the second mounting hole 211 on the first plastic part 200 and the fourth mounting hole 410 on the connecting block 400 from the side of the pole group in the first direction, realizing the fixation of the pole 500 on the cover plate body 100.

[0025] A first limiting groove 120 is provided circumferentially on the first mounting hole 110 on the cover plate body 100. The first limiting groove 120 is located on the end face of the cover plate body 100 away from the electrode assembly. The support member 600 is annular and sleeved on the outside of the electrode post 500. The support member 600 is at least partially embedded in the first limiting groove 120, and the support member 600 is located in the second mounting hole 211 of the first plastic part 200. Along the first direction, the opposite two end faces of the support member 600 abut against the bottom wall of the first limiting groove 120 and the end face of the connecting block 400 facing the cover plate body 100, respectively. On the one hand, during the assembly of the cover plate body 100 and the first plastic part 200, the support member 600 provides good guidance and positioning for the first plastic part 200, preventing the center of the first plastic part 200 from shifting and ensuring that the center of the first mounting hole 110 on the cover plate body 100 coincides with the center of the second mounting hole 211 on the first plastic part 200, resulting in high assembly accuracy. On the other hand, during the riveting process between the electrode post 500 and the connecting block 400, the support member 600 mainly provides support for the connecting block 400, greatly reducing the pressure on the first plastic part 200. The support member 600 provides good protection for the first plastic part 200, preventing it from cracking due to excessive pressure, which would affect the insulation performance of the first plastic part 200. In addition, when the first plastic part 200 undergoes creep under high temperature conditions, the support member 600 can still continuously provide support between the cover plate body 100 and the connecting block 400, preventing the electrode post 500 from sinking and ensuring good sealing performance of the cell cover plate. For example, the support 600 can be one of ceramic material, mica material, or PEEK material. All of these materials have high strength, high elastic modulus, high hardness, creep resistance, high temperature resistance, and low compressive deformation properties, ensuring that the support 600 is not easily compressed and deformed, and can provide reliable support for the connecting block 400.

[0026] Optionally, the fourth mounting hole 410 is further provided with a riveting step 420 in the circumferential direction. The end of the pole post 500 away from the pole group passes sequentially through the third mounting hole 310, the first mounting hole 110, the second mounting hole 211, and the fourth mounting hole 410 from the side where the pole group is located, and is then riveted to the riveting step 420. After the end of the pole post 500 away from the pole group is riveted, a protrusion 5221 is formed to press the connecting block 400 onto the first plastic part 200, thereby pressing the first plastic part 200 onto the cover plate body 100.

[0027] See Figure 3 and Figure 4 Along the second direction, the width of the support member 600 is A, and the width of the contact surface between the support member 600 and the bottom wall of the first limiting groove 120 is a. The aforementioned second direction is... Figure 3The Y-axis direction shown is also the width direction of the cover plate body 100. The relationship between A and a satisfies: 0.35 ≤ a / A ≤ 0.75. For example, the value of a / A can be 0.35, 0.45, 0.55, 0.65, or 0.75, etc. By limiting the value of a / A within the above range, it is ensured that the bottom wall of the first limiting groove 120 of the cover plate body 100 has a wide contact surface with the support member 600, and the cover plate body 100 can provide good support for the support member 600. Therefore, when the pole post 500 is riveted to the connecting block 400, the support member 600 can support the connecting block 400 well, ensuring a high connection strength between the pole post 500 and the connecting block 400 after riveting. The value of a / A should not be too small, otherwise the contact surface between the bottom wall of the first limiting groove 120 of the cover plate body 100 and the support member 600 will be too narrow, resulting in poor limiting and supporting effects of the cover plate body 100 on the support member 600. This will reduce the positioning accuracy of the support member 600 during assembly with the cover plate body 100 and decrease the supporting effect of the cover plate body 100 on the support member 600. The value of a / A should also not be too large, otherwise the size of the first limiting groove 120 will be too large, which will have a greater impact on the mechanical strength of the cover plate body 100, reduce the structural strength of the cover plate body 100, increase the size of the support member 600, waste material costs, and the support member 600 will occupy a large space along the second direction, making it unsuitable for use with some narrower battery cell covers.

[0028] Optionally, the value of A ranges from 1.2mm to 3.5mm. For example, the value of A can be 1.2mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, or 3.5mm, etc. The value of a ranges from 0.45mm to 2.5mm. For example, the value of a can be 0.45mm, 0.55mm, 0.80mm, 1.00mm, 1.50mm, 2.00mm, or 2.50mm, etc.

[0029] Along the first direction, the thickness of the support member 600 is B, and the depth of the first limiting groove 120 is b. The relationship between B and b satisfies: 0.35 ≤ b / B ≤ 0.7. For example, the value of b / B can be 0.35, 0.45, 0.55, 0.65, or 0.70, etc. By limiting the value of b / B within the above range, the positioning effect of the first limiting groove 120 of the cover plate body 100 on the support member 600 is ensured to be better, and the positioning accuracy of the support member 600 on the cover plate body 100 is guaranteed to be high. As a result, the support member 600 can provide good guidance for the first plastic part 200, and the assembly accuracy and assembly yield of the battery cell cover plate are high. The value of b / B should not be too small, otherwise the first limiting groove 120 of the cover plate body 100 will have poor limiting effect on the support member 600, and the support member 600 will easily come out of the first limiting groove 120, reducing the positioning accuracy of the support member 600 when assembling with the cover plate body 100. The value of b / B should also not be too large, otherwise the depth dimension of the first limiting groove 120 needs to be increased, which will have a greater impact on the mechanical strength of the cover plate body 100, reduce the structural strength of the cover plate body 100, and increase the size of the support member 600, wasting material costs. Moreover, the support member 600 will occupy a large space along the first direction, increasing the overall thickness of the cell cover plate.

[0030] Optionally, the value of B ranges from 1.0mm to 2.5mm. For example, the value of B can be 1.0mm, 1.2mm, 1.5mm, 2.0mm, or 2.5mm, etc. The value of b ranges from 0.4mm to 1.5mm. For example, the value of b can be 0.40mm, 0.55mm, 0.80mm, 1.00mm, 1.20mm, or 1.50mm, etc.

[0031] See also Figure 1 and Figure 3 The pole post 500 includes a plate portion 510 and a post portion 520 connected to each other. The post portion 520 passes sequentially through a third mounting hole 310, a first mounting hole 110, a second mounting hole 211, and a fourth mounting hole 410 along a first direction and is riveted to a riveting step 420. A protrusion 5221 is formed at the end of the post portion 520 away from the plate portion 510. The plate portion 510 is located on the side of the second plastic part 300 away from the cover plate body 100. The protrusion 5221 and the plate portion 510 respectively press and fix the first plastic part 200 and the second plastic part 300 onto the cover plate body 100, and at the same time fix the pole post 500 onto the cover plate body 100.

[0032] Optionally, the column portion 520 in this embodiment includes a first column 521 and a second column 522. One end of the first column 521 along a first direction is connected to the plate portion 510, and the other end of the first column 521 along the first direction is connected to the second column 522. The end of the second column 522 away from the first column 521 is riveted to the connecting block 400 to form the aforementioned protrusion 5221. The diameter of the second column 522 is smaller than the diameter of the first column 521. A support step 5222 is formed between the first column 521 and the second column 522. The end face of the connecting block 400 located circumferentially in the fourth mounting hole 410, facing the cover plate body 100, abuts against the support step 5222. Through the design of the support step 5222, the connecting block 400 can be riveted to the pole post 500 to provide auxiliary support for the connecting block 400.

[0033] Furthermore, the cell cover also includes a sealing ring 700, which includes a first sealing portion 710 and a second sealing portion 720. The first sealing portion 710 is circumferentially disposed around the second sealing portion 720. Along a first direction, the opposite end faces of the first sealing portion 710 abut against the plate portion 510 and the cover body 100, respectively, sealing the gap between the plate portion 510 and the cover body 100. The second sealing portion 720 is sleeved on the outside of the column portion 520 and located between the outer peripheral wall of the column portion 520 and the inner wall of the first mounting hole 110. Along the first direction, the opposite end faces of the second sealing portion 720 abut against the plate portion 510 and the support member 600, respectively, sealing the gap between the column portion 520 and the cover body 100. Through the provision of the sealing ring 700, the gap between the cover body 100 and the electrode post 500 is sealed, ensuring good sealing performance of the cell cover.

[0034] See also Figure 4Along the first direction, the end face of the second sealing part 720 on the side away from the electrode group is not higher than the end face of the cover plate body 100 on the side away from the electrode group. Specifically, along the first direction, the height difference between the end face of the second sealing part 720 on the side away from the electrode group and the end face of the cover plate body 100 on the side away from the electrode group is h, and the value of h is in the range of 0mm≤h≤0.5mm. For example, the value of h can be 0mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm or 0.5mm, etc. By limiting the value of h to the above range, on the one hand, it is convenient to assemble the support member 600 on the cover plate body 100, and the support member 600 cannot be effectively positioned before assembly and riveting. If the second sealing part 720 is higher than the end face of the cover plate body 100 on the side away from the electrode group, the support member 600 cannot be pre-installed on the cover plate body 100, which will affect the subsequent assembly of the first plastic part 200 and the connecting block 400 on the cover plate body 100, and reduce the assembly yield and assembly accuracy. On the other hand, it also avoids excessive compression of the second sealing part 720 of the sealing ring 700, which would put more pressure on the support member 600.

[0035] In some embodiments, the first plastic part 200 includes a plastic part body 210 and a limiting plate 220 disposed circumferentially on the plastic part body 210. The plastic part body 210 is located between the connecting block 400 and the cover plate body 100 along a first direction, serving to insulate and isolate the connecting block 400 and the cover plate body 100. The limiting plate 220 extends away from the electrode group along the first direction, and the plastic part body 210 and the limiting plate 220 form a receiving groove 221 for mounting the connecting block 400. The receiving groove 221 provides good positioning for the connecting block 400, ensuring smooth riveting of the electrode post 500 to the connecting block 400, which is beneficial to improving the assembly accuracy of the cell cover plate.

[0036] See also Figure 1 , Figure 3 and Figure 5 In this embodiment, the cylindrical portion 520 of the electrode post 500 has an oblong cross-section in the YZ plane, with its dimension along the third direction being larger than its dimension along the second direction. This increases the current-carrying area of ​​the electrode post 500, making it suitable for use in some high-current cells. The aforementioned third direction is... Figure 1The Z-axis direction is also the length direction of the cover plate body 100. Both the support member 600 and the sealing ring 700 are annular and structurally contoured to the cylindrical portion 520 of the pole post 500. Similarly, the first mounting hole 110, the second mounting hole 211, the third mounting hole 310, and the fourth mounting hole 410 are also structurally contoured to the cylindrical portion 520 of the pole post 500 to fit the shape of the pole post 500. The plate portion 510 of the pole post 500 has a rectangular cross-section in the YZ plane. A second limiting groove 320 with a rectangular cross-section is provided on the end face of the second plastic part 300 facing the pole assembly. The plate portion 510 is at least partially accommodated within the second limiting groove 320. Through the cooperation between the plate portion 510 and the second limiting groove 320, the relative position of the pole post 500 and the second plastic part 300 is accurate and less prone to deflection, which helps improve the stability of the pole post 500 fixed on the cover plate body 100.

[0037] Furthermore, in this embodiment, the connecting block 400 is a long strip plate, and its dimension along the third direction is greater than its dimension along the second direction. The dimension of the plastic body 210 of the first plastic part 200 along the third direction is greater than its dimension along the second direction. Along the second direction, the width of the contact surface between the connecting block 400 and the plastic body 210 is e1, and the value of e1 is in the range of 0.5mm≤e1≤8mm. For example, the value of e1 can be 0.50mm, 1.0mm, 2.0mm, 3.0mm, 4.0mm, 5.0mm, 6.0mm, 7.0mm, or 8.0mm, etc. By limiting the value of e1 to the above range, the first plastic part 200 can provide good support for the connecting block 400, and the limiting plate 220 of the first plastic part 200 can provide good positioning for the connecting block 400, thereby ensuring that the first plastic part 200 can be stably pressed and fixed on the cover plate body 100, and the assembly accuracy is high. Of course, the specific value of e1 needs to be adjusted according to the width of the cover body 100 along the second direction. It should be ensured that there is a certain space between the limiting plate 220 of the first plastic part 200 and the side of the cover body 100 along the second direction, so as to facilitate the assembly of the cover body 100 with the housing of the battery cell.

[0038] See also Figure 5Along the third direction, the width of the contact surface between the connecting block 400 and the plastic body 210 is e2, and the value of e2 ranges from 0.5mm to 30mm. For example, the value of e2 can be 0.50mm, 1.0mm, 2.0mm, 5.0mm, 10.0mm, 15.0mm, 20.0mm, 25.0mm, or 30.0mm, etc. By limiting the value of e2 within the above range, the first plastic part 200 can provide good support for the connecting block 400, and the limiting plate 220 of the first plastic part 200 can provide good positioning for the connecting block 400, thereby ensuring that the first plastic part 200 can be stably pressed and fixed on the cover body 100 with high assembly accuracy. Of course, the specific value of e2 also needs to be adjusted according to the length of the cover body 100 along the third direction. Sufficient space should be left on at least one side of the first plastic part 200 along the third direction on the cover body 100 to arrange an explosion-proof valve to ensure the safety of the battery cell.

[0039] The values ​​of the relevant dimensional parameters A, a, a / A, B, b, b / B, e1, and e2 of the above-mentioned battery cell cover plate are verified using samples from some specific implementation cases. See Table 1 for details.

[0040] Table 1 In Examples 1 to 8, the values ​​of A, a, a / A, B, b, b / B, e1, and e2 all meet their respective dimensional constraints. When the electrode post 500 is directly welded to the electrode lug of the electrode group, or when the electrode post 500 is connected to the electrode lug of the electrode group by welding through a connecting piece, the first plastic part 200 does not have a melting deformation problem, the support member 600 provides good support for the cover plate body 100 and the connecting block 400, the electrode post 500 does not have a sinking problem, the sealing performance of the cell cover plate is good, and the helium leak detection rate is less than 9.9 × 10⁻⁶. -7 Pa·m 3 / s, after the cell cover plate and the housing are assembled, they are baked at high temperature without any leakage or other abnormalities, and the product is in good condition.

[0041] In Comparative Example 1, the value of a is less than the minimum value of 0.45mm≤a≤2.5mm, and the value of a / A is less than the minimum value of 0.35≤a / A≤0.75. The width of the contact surface between the support member 600 and the bottom wall of the first limiting groove 120 on the cover plate body 100 along the second direction is small, the support effect is not obvious, the positioning effect is reduced, the first plastic part 200 shows slight melting deformation after high temperature baking, the pole post 500 sinks slightly, the helium leak detection rate does not meet the standard, and the product is defective.

[0042] In Comparative Example 2, the value of b is less than the minimum value of 0.4mm≤b≤1.5mm, and the value of b / B is less than the minimum value of 0.35≤b / B≤0.7. The height of the contact surface between the support member 600 and the side wall of the first limiting groove 120 on the cover plate body 100 along the first direction is small, resulting in poor support and limiting effects. After high-temperature baking, the first plastic part 200 shows slight melting deformation, the pole post 500 sinks slightly, the helium leak detection rate does not meet the standard, and the product is defective.

[0043] In Comparative Example 3, the value of e1 is less than the minimum value of 0.5mm≤e1≤8mm. At this time, the width of the contact surface between the plastic body 210 of the first plastic part 200 and the connecting block 400 along the second direction is small. When the pole post 500 is riveted to the connecting block 400, the support effect of the first plastic part 200 on the connecting block 400 is poor. After high-temperature baking, the first plastic part 200 shows slight melting deformation, the pole post 500 sinks slightly, the helium leak detection rate does not meet the standard, and the product is defective.

[0044] In Comparative Example 4, the value of e2 is less than the minimum value of 0.5mm≤e2≤30mm. At this time, the width of the contact surface between the plastic body 210 of the first plastic part 200 and the connecting block 400 along the third direction is small. When the pole post 500 is riveted to the connecting block 400, the support effect of the first plastic part 200 on the connecting block 400 is poor. After high-temperature baking, the first plastic part 200 shows slight melting deformation, the pole post 500 sinks slightly, the helium leak detection rate does not meet the standard, and the product is defective.

[0045] In Comparative Example 5, the value of e2 is greater than the maximum value of 0.5mm≤e2≤30mm. At this time, the width of the contact surface between the plastic body 210 of the first plastic part 200 and the connecting block 400 along the third direction is too large, occupying a large space and affecting the arrangement of other structural components (e.g., explosion-proof valves) on the cover plate body 100. Moreover, the size of the plastic body 210 of the first plastic part 200 along the third direction is too large, making it difficult to guarantee the dimensional accuracy of the first plastic part 200 during injection molding. Warping is likely to occur at the edges, preventing it from fitting tightly with the cover plate body 100. The helium leak detection rate does not meet the standard, resulting in defective products.

[0046] In Comparative Example 6, the value of e1 is greater than the maximum value of 0.5mm≤e1≤8mm. At this time, the width of the contact surface between the plastic body 210 of the first plastic part 200 and the connecting block 400 along the second direction is too large, occupying a large space. The size of the cover body 100 along the second direction needs to be increased accordingly. The large width of the cover body 100 along the second direction is not conducive to the thin and light design of the battery cell. Moreover, the large size of the plastic body 210 of the first plastic part 200 along the second direction makes it difficult to ensure the dimensional accuracy of the first plastic part 200 during injection molding. Warping is likely to occur at the edges, and it cannot fit tightly with the cover body 100. The helium leak detection rate does not meet the standard, and the product is defective.

[0047] In Comparative Example 7, the value of b is greater than the maximum value of 0.4mm≤b≤1.5mm, and the value of b / B is greater than the maximum value of 0.35≤b / B≤0.7. The height of the contact surface between the support member 600 and the side wall of the first limiting groove 120 on the cover plate body 100 along the first direction is too large. Correspondingly, the height of the fit between the support member 600 and the plastic body 210 of the first plastic part 200 is too small, resulting in poor positioning effect of the first plastic part 200. The first plastic part 200 is prone to positional deviation relative to the cover plate body 100, which leads to a decrease in the yield of riveting between the pole post 500 and the connecting block 400. The first plastic part 200 is prone to cracking, the helium leak detection rate does not meet the standard, and the product is defective.

[0048] In Comparative Example 8, the value of a is greater than the maximum value of 0.45mm≤a≤2.5mm, and the value of a / A is greater than the maximum value of 0.35≤a / A≤0.75. The width of the contact surface between the support member 600 and the bottom wall of the first limiting groove 120 on the cover body 100 along the second direction is too large. The size of the mating part of the support member 600 and the second sealing part 720 of the sealing ring 700 is too small. When assembling the battery cell cover, the sealing ring 700 is prone to misalignment, resulting in a decrease in sealing performance, a failure to meet the helium leak detection rate, and product defects.

[0049] In summary, when all the above parameters meet their corresponding size limitations, the support 600 can reliably support the cover body 100 and the connecting block 400, the pole post 500 does not sink, the cell cover has good sealing performance, and there are no abnormalities such as leakage.

[0050] The present invention also provides a battery cell, including the aforementioned battery cell cover plate. By using the aforementioned battery cell cover plate, the assembly accuracy and assembly yield of the battery cell cover plate can be guaranteed, while avoiding adverse effects on the first plastic part 200 during the riveting process of the terminal post 500, ensuring good insulation performance of the first plastic part 200, and good sealing performance of the battery cell cover plate.

[0051] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A battery cell cover plate, characterized in that, include: The cover plate body has a first mounting hole and a first limiting groove in the circumferential direction of the first mounting hole. The first limiting groove is located on the end face of the cover plate body away from the electrode group. A first plastic component is disposed on the side of the cover plate body away from the electrode assembly along a first direction, and the first plastic component is provided with a second mounting hole. The second plastic part is disposed on the side of the cover plate body close to the electrode group along the first direction, and the second plastic part is provided with a third mounting hole. A connecting block is disposed on the side of the first plastic part away from the cover plate body along the first direction. The connecting block is provided with a fourth mounting hole, and the fourth mounting hole is provided with a riveting step in the circumferential direction. The pole post passes sequentially through the third mounting hole, the first mounting hole, the second mounting hole, and the fourth mounting hole from the side where the pole group is located along the first direction and is then riveted to the riveting step; A support member, which is annular and sleeved on the pole post, is at least partially embedded in the first limiting groove; the opposite two end faces of the support member along the first direction abut against the bottom wall of the first limiting groove and the end face of the connecting block facing the cover plate body, respectively.

2. The cell cover plate according to claim 1, characterized in that, Along the second direction, the width of the support member is A, and the width of the contact surface between the support member and the bottom wall of the first limiting groove is a; The relationship between A and a satisfies: 0.35 ≤ a / A ≤ 0.75; The range of values ​​for A is: 1.2mm ≤ A ≤ 3.5mm; The range of values ​​for a is: 0.45mm ≤ a ≤ 2.5mm.

3. The cell cover plate according to claim 1, characterized in that, Along the first direction, the thickness of the support member is B, and the depth of the first limiting groove is b; The relationship between B and b satisfies: 0.35 ≤ b / B ≤ 0.7; The value of B is in the range of: 1.0mm ≤ B ≤ 2.5mm; The value of b is in the range of 0.4mm ≤ b ≤ 1.5mm.

4. The cell cover plate according to claim 1, characterized in that, The pole includes a plate portion and a column portion connected to each other. The column portion passes through the third mounting hole, the first mounting hole, the second mounting hole and the fourth mounting hole in sequence along the first direction and is riveted to the riveting step. The plate portion is located on the side of the second plastic part away from the cover plate body.

5. The cell cover plate according to claim 4, characterized in that, The column portion includes a first column and a second column. One end of the first column along a first direction is connected to the plate portion, and the other end of the first column along the first direction is connected to the second column. The diameter of the second column is smaller than the diameter of the first column, and a support step for supporting the connecting block is formed between the first column and the second column.

6. The cell cover plate according to claim 4, characterized in that, The cell cover also includes a sealing ring, which includes a first sealing part and a second sealing part. The first sealing part is arranged around the second sealing part in the circumferential direction. Along the first direction, the opposite end faces of the first sealing part abut against the plate part and the cover body, respectively. The second sealing part is sleeved on the outside of the column part and is located between the outer peripheral wall of the column part and the inner wall of the first mounting hole.

7. The cell cover plate according to claim 6, characterized in that, Along the first direction, the end face of the second sealing part on the side away from the electrode group is not higher than the end face of the cover plate body on the side away from the electrode group; along the first direction, the height difference between the end face of the second sealing part on the side away from the electrode group and the end face of the cover plate body on the side away from the electrode group is h; The value range of h is: 0mm≤h≤0.5mm.

8. The cell cover plate according to claim 1, characterized in that, The first plastic part includes a plastic part body and a limiting plate disposed around the plastic part body. The limiting plate extends away from the pole group along a first direction. The plastic part body and the limiting plate form a receiving groove for mounting the connecting block. Along the second direction, the width of the contact surface between the connecting block and the plastic body is e1; The value range of e1 is: 0.5mm≤e1≤8mm.

9. The cell cover plate according to claim 8, characterized in that, Along a third direction, the width of the contact surface between the connecting block and the plastic body is e2; The value range of e2 is: 0.5mm≤e2≤30mm.

10. A battery cell, characterized in that, The cell cover plate included in any one of claims 1-9.

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