Battery cell cover plate and battery cell

Abstract

This invention belongs to the field of battery technology, specifically disclosing a cell cover and a cell. In the cell cover, a first plastic part and a connecting block are sequentially disposed on the side of the cover body away from the electrode assembly. The electrode post passes sequentially through the cover body, the first plastic part, and the connecting block from the side where the electrode assembly is located, and is then riveted to the connecting block body of the connecting block. The first plastic part has an elastic buffer on its body, which provides support and cushioning during the riveting of the electrode post, preventing damage or cracking of the first plastic part due to excessive riveting force. The connecting block body has a protective insert, which increases the structural strength of the connecting block body, improves its torsional resistance, and prevents deformation of the connecting block body during riveting, thus avoiding damage or cracking of the first plastic part due to pressure from the connecting block. This invention also provides a cell, including the aforementioned cell cover.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a cell cover plate and a cell. Background Technology

[0002] In existing battery cell covers, the terminals are generally fixed to the cover body by riveting. For example, some battery cell covers include a cover body, an upper plastic part, a lower plastic part, a terminal, and a riveting block. The upper and lower plastic parts are respectively located on both sides of the cover body, and the riveting block is located on the side of the upper plastic part away from the cover body. The terminal passes through the lower plastic part, the cover body, the upper plastic part, and the riveting block in sequence from the side where the lower plastic part is located, and then is riveted to the riveting block.

[0003] However, during the riveting process between the pole and the rivet block, the rivet block may deform or crack due to excessive axial and radial riveting pressure, resulting in a low assembly yield. Moreover, if the strength of the upper plastic part is insufficient during the riveting process, cracking and damage may also occur, causing the insulation of the cell cover to fail and reliability to be compromised. Summary of the Invention

[0004] The purpose of this invention is to provide a cell cover plate and a cell that can absorb and buffer some of the pressure during the riveting of the terminal posts, thereby protecting the first plastic part and the connecting block and preventing them from deforming or cracking. This results in a high assembly yield and high reliability.

[0005] To achieve this objective, the present invention adopts the following technical solution: On one hand, the present invention provides a battery cell cover plate, comprising: A cover plate body, wherein the cover plate body is provided with a first mounting hole; A first plastic component is disposed on the side of the cover plate body away from the electrode group along a first direction. The first plastic component includes a plastic component body and an elastic buffer. The plastic component body is provided with a second mounting hole and a mounting groove. The mounting groove is located circumferentially to the second mounting hole. The opening of the mounting groove faces the side away from the cover plate body. The bottom of the mounting groove is provided with a through hole penetrating the plastic component body. The elastic buffer is embedded in the mounting groove. The first direction is the thickness direction of the battery cell cover plate. A connecting block is disposed on the side of the first plastic part away from the cover plate body along a first direction. The connecting block includes a connecting block body and a protective insert. The connecting block body is provided with a third mounting hole. The protective insert is disposed on the side of the connecting block body along a second direction and is located on the side of the connecting block body close to the electrode group along the first direction. The protective insert is adjacent to the third mounting hole along the second direction, which is the width direction of the cell cover plate. The pole post passes sequentially through the first mounting hole, the second mounting hole, and the third mounting hole from the side where the pole group is located along the first direction and is then riveted to the body of the connecting block.

[0006] Optionally, the pole post includes a column portion, which passes through the first mounting hole, the second mounting hole, and the third mounting hole; in a cross section perpendicular to the first direction, the cross section of the column portion is waist-shaped, and the cross sections of the first mounting hole, the second mounting hole, and the third mounting hole are also waist-shaped.

[0007] Optionally, along the first direction, the height of the elastic buffer protruding from the end face of the plastic body on the side opposite to the pole group is H; The value range of H is: 0.04mm≤H≤0.08mm.

[0008] Optionally, multiple mounting slots are provided, and the multiple mounting slots are respectively arranged on both sides of the second mounting hole along a third direction, where the third direction is the length direction of the cell cover plate; the mounting slots located on the same side of the second mounting hole along the third direction form a slot group, and the multiple mounting slots in each slot group are arranged at circumferential intervals in the second mounting hole; the elastic buffer corresponds to each mounting slot; In a cross-section perpendicular to the first direction, the cross-sectional area of ​​each of the mounting slots is S1, and the cross-sectional area of ​​the second mounting hole is S2; the number of all the mounting slots is N. The relationship between N, S1 and S2 satisfies: 0.25≤(N×S1) / S2≤0.7.

[0009] Optionally, the connecting block body is provided with a slot on each side along the second direction, and two protective inserts are provided, each of the protective inserts being inserted into one of the slots along the first direction; The protective insert has a limiting boss on one side facing the connecting block body along the second direction. The limiting boss is located at the end of the protective insert along the third direction and extends outward along the third direction. The corresponding position of the slot has a first limiting part. The limiting boss cooperates with the first limiting part to limit the displacement of the protective insert along the second direction.

[0010] Optionally, the connecting block body is provided with a material feeding groove on each side along the second direction, the material feeding groove is connected to the slot, and the protective insert is provided with a plurality of support platforms on one side of the connecting block body along the second direction. The plurality of support platforms are located in the middle of the protective insert along the third direction, and two adjacent support platforms are spaced apart along the third direction. At least a portion of the plurality of support platforms extends into the material feeding groove. Along the third direction, the size of the third mounting hole is L1, the length of the main body of the protective insert is L2, the size of the material feeding groove is L3, and the length of the connecting block body is A; The relationship between L1 and L2 satisfies: 4mm≤L2-L1≤10mm; The relationship between L2 and L3 satisfies: 0.25 ≤ L3 / L2 ≤ 0.5; The relationship between L2 and A satisfies: 0.25 ≤ L2 / A ≤ 0.45.

[0011] Optionally, the limiting boss includes a first limiting inclined surface, and the angle between the first limiting inclined surface and the side of the connecting block body opposite to each other along the second direction is α; The range of values ​​for α is: 10°≤α≤60°; And / or, in the two outermost support platforms, a second limiting inclined surface is provided on the side of the opposite wall of the material feeding trough along a third direction, and a second limiting part is provided on the opposite wall of the material feeding trough along a third direction, and the second limiting inclined surface cooperates with the second limiting part; wherein, the included angle between the second limiting inclined surface and the opposite wall of the material feeding trough along a second direction is β; The range of β is: 10°≤β≤80°.

[0012] Optionally, along the second direction, the size of the third mounting hole is W1, the distance between the opposite walls of the two feed grooves along the second direction is W2, the distance between the opposite walls of the two slots along the second direction is W3, and the distance between the end faces of the two protective inserts facing away from each other is B. The relationship between W1 and B satisfies: 0.25 ≤ W1 / B ≤ 0.55; The relationship between W2 and W3 satisfies: 1mm≤W3-W2≤6mm.

[0013] Optionally, the connecting block body is provided with a stepped portion in the circumferential direction. The stepped portion includes a first stepped surface perpendicular to the first direction and a second stepped surface parallel to the first direction. Along the first direction, the height of the stepped portion is the same as the depth of the slot, and the first stepped surface is coplanar with the bottom of the slot. Along the first direction, the height of the connecting block body is T1, and the depth of the slot is T2; The relationship between T1 and T2 satisfies: 0.5mm≤T1-T2≤1.5mm.

[0014] On the other hand, the present invention provides a battery cell including the battery cell cover plate of any of the above embodiments.

[0015] The beneficial effects of this invention are as follows: This invention provides a battery cell cover plate, comprising a cover plate body, a first plastic part, a connecting block, and a terminal post. The first plastic part and the connecting block are sequentially disposed on the side of the cover plate body away from the electrode assembly. The terminal post passes through the cover plate body, the first plastic part, and the connecting block sequentially from the side where the electrode assembly is located, and is then riveted to the connecting block body of the connecting block. The first plastic part includes a plastic part body and an elastic buffer. The elastic buffer is disposed in a mounting groove on the plastic part body, with the opening of the mounting groove facing away from the cover plate body. The bottom of the mounting groove has a through hole penetrating the plastic part body. By providing an elastic buffer on the first plastic part, it can provide support and buffer during the riveting of the terminal post, preventing excessive riveting force that could damage or crack the first plastic part. The through hole at the bottom of the mounting groove allows material to pass through the elastic buffer, avoiding adverse damage to the cover plate body caused by material pressing. The connecting block body of the connecting block has a protective insert, which increases the structural strength of the connecting block body, improves its torsional resistance, and prevents the connecting block body from deforming during riveting, thus avoiding damage or cracking of the first plastic part due to compression.

[0016] The present invention also provides a battery cell, including the aforementioned battery cell cover plate. This battery cell cover plate has a high yield rate during assembly; the first plastic part and the connecting block are not prone to deformation or cracking, resulting in high reliability. Furthermore, the flatness of the connecting block after riveting is high, facilitating subsequent welding with the battery cell sheet. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the battery cell cover plate provided in an embodiment of the present invention; Figure 2 This is an exploded view of the battery cell cover plate provided in the embodiment of the present invention; Figure 3 This is a top view of the battery cell cover plate provided in an embodiment of the present invention; Figure 4 yes Figure 3 Sectional view of section I-I; Figure 5 yes Figure 4 Enlarged view of a section at point III; Figure 6 yes Figure 3 Sectional view of section II-II; Figure 7 This is an exploded view of the first plastic part provided in the embodiment of the present invention; Figure 8 This is an exploded view of the first plastic part provided in an embodiment of the present invention from another perspective; Figure 9 This is a top view of the first plastic part provided in an embodiment of the present invention; Figure 10 yes Figure 9 Sectional view of section IV-IV; Figure 11 yes Figure 10 A magnified view of section V; Figure 12 This is a schematic diagram of the structure of the connecting block provided in an embodiment of the present invention; Figure 13 This is an exploded view of the connecting block provided in the embodiment of the present invention; Figure 14 This is a bottom view of the connecting block provided in an embodiment of the present invention; Figure 15 This is a partially enlarged view of the connecting block body and the protective insert after assembly in an embodiment of the present invention; Figure 16 yes Figure 14 Sectional view of section VI-VI; Figure 17 yes Figure 14 Sectional view of section VII-VII.

[0018] In the picture: 100. Cover plate body; 101. First mounting hole; 200. First plastic part; 210. Plastic part body; 211. Second mounting hole; 212. Mounting groove; 213. Through hole; 220. Elastic buffer; 230. Limiting plate; 231. Receiving groove; 232. Limiting step; 300. Connecting block; 310. Connecting block body; 311. Third mounting hole; 3111. Riveting step; 3112. Countersunk groove; 312. Slot; 3121. First limiting part; 31 3. Material feeding chute; 3131. Second limiting part; 314. Step part; 3141. First step surface; 3142. Second step surface; 320. Protective insert; 321. Limiting boss; 3211. First limiting inclined surface; 322. Support platform; 3221. Material feeding space; 3222. Second limiting inclined surface; 400. End post; 410. Column part; 411. Protrusion; 420. Plate part; 500. Second plastic part; 501. Fourth mounting hole; 600. Sealing element. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0020] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0023] like Figures 1-6 As shown, this embodiment provides a battery cell cover plate, which includes a cover plate body 100, a first plastic part 200, a connecting block 300, and a terminal post 400. The first plastic part 200 is disposed on the side of the cover plate body 100 away from the electrode group along a first direction, and the connecting block 300 is disposed on the side of the first plastic part 200 away from the cover plate body 100 along the first direction. The cover plate body 100, the first plastic part 200, and the connecting block 300 are stacked sequentially along the first direction. The terminal post 400 passes sequentially through the cover plate body 100, the first plastic part 200, and the connecting block 300 from the side where the electrode group is located along the first direction and is then riveted to the connecting block 300. The first direction is the thickness direction of the battery cell cover plate, which is also... Figure 1 The X-axis direction is shown in the figure.

[0024] Specifically, the cover plate body 100 is provided with a first mounting hole 101 for the electrode post 400 to pass through. The first plastic part 200 includes a plastic part body 210 and an elastic buffer 220. The plastic part body 210 is sandwiched between the cover plate body 100 and the connecting block 300 along a first direction, and the cover plate body 100 and the connecting block 300 are insulated by the plastic part body 210 and the elastic buffer 220. The plastic part body 210 is provided with a second mounting hole 211 and a mounting groove 212. The mounting groove 212 is located circumferentially to the second mounting hole 211, and the second mounting hole 211 is used for the electrode post 400 to pass through. The opening of the mounting groove 212 faces away from the cover plate body 100, and the elastic buffer 220 is embedded in the mounting groove 212. The elastic buffer 220 provides good support and buffering during the riveting of the electrode post 400, preventing excessive riveting force from causing damage and cracking of the first plastic part 200. Furthermore, the bottom of the mounting groove 212 is provided with a through hole 213 that penetrates the plastic body 210. When the pole post 400 and the connecting block 300 are riveted, the elastic buffer 220 deforms. The through hole 213 is used to allow the deformed elastic buffer 220 to pass through, thereby avoiding excessive pressure on the cover plate body 100 and avoiding adverse effects on the cover plate body 100 during pressing.

[0025] Optionally, the plastic body 210 can be made of an insulating material, such as PP, PE, or PPS. The elastic buffer 220 can be integrally molded with the plastic body 210 by injection molding. The elastic buffer 220 is made of an insulating material and has no exposed assembly gap with the first plastic part 200, reducing the risk of insulation failure of the cover body 100. The elastic buffer 220 has excellent insulation properties and compressibility, and can deform under pressure.

[0026] The connecting block 300 includes a connecting block body 310 and a protective insert 320. The connecting block body 310 has a third mounting hole 311. The electrode post 400 passes sequentially through the first mounting hole 101, the second mounting hole 211, and the third mounting hole 311 from the side where the electrode group is located along a first direction and is then riveted to the connecting block body 310. The protective insert 320 is disposed on the side of the connecting block body 310 along a second direction, and is located on the side of the connecting block body 310 closer to the electrode group along the first direction. The protective insert 320 is adjacent to the third mounting hole 311 along the second direction, which is the width direction of the cell cover plate. Figure 1The Y-axis direction is shown in the diagram. The connecting block body 310 is made of a metal material, such as aluminum. The protective insert 320 is made of a material with high mechanical strength and good thermal conductivity (not limited to aluminum or copper). The protective insert 320 can improve the structural strength of the connecting block 300, making it less prone to deformation during riveting, avoiding compression of the first plastic part 200 and causing damage or cracking, while also giving the cell cover plate higher resistance to thrust and torsion. Furthermore, because the protective insert 320 has good thermal conductivity, it can reduce the heat impact when welding the electrode post 400 to the connecting block body 310, which is beneficial for accelerating the heat dissipation of the connecting block body 310 and preventing the first plastic part 200 from deforming after being heated.

[0027] Furthermore, the cell cover plate in this embodiment includes a second plastic part 500, which is disposed on the side of the cover plate body 100 near the electrode group along the first direction. The second plastic part 500 is provided with a fourth mounting hole 501. The connecting block body 310 is provided with a riveting step 3111 and a groove 3112 on the side away from the electrode group. The groove 3112 is arranged circumferentially on the riveting step 3111. The electrode post 400 includes a column part 410 and a plate part 420. The plate part 420 is located on the side of the second plastic part 500 near the electrode group. The column part 410 passes through the fourth mounting hole 501, the first mounting hole 101, the second mounting hole 211, and the third mounting hole 311 and is riveted to the riveting step 3111 on the connecting block body 310. The column part 410 deforms along its circumferential direction to form a protrusion 411. The protrusion 411 and the plate part 420 cooperate to fix the electrode post 400 on the cover plate body 100. Within a cross-section perpendicular to the first direction, the plate portion 420 has a rectangular cross-section, and the column portion 410 has an oblong cross-section. The column portion 410 includes two straight wall surfaces opposite each other along the second direction and two arc-shaped wall surfaces opposite each other along the third direction. The third direction is the length direction of the cell cover plate, which is also... Figure 1 The Z-axis direction is shown in the diagram. The shapes of the first mounting hole 101, the second mounting hole 211, the third mounting hole 311, and the fourth mounting hole 501 match the cylindrical portion 410, and the cross-sections of the first mounting hole 101, the second mounting hole 211, the third mounting hole 311, and the fourth mounting hole 501 are also oblong. By adopting the above design, the current-carrying area of ​​the terminal post 400 is greatly increased without increasing the number of terminal posts 400, enabling a larger current carrying capacity and meeting the fast charging requirements of the battery cell.

[0028] The cell cover also includes a sealing element 600, which is sleeved on the outside of the post 410 of the electrode post 400 and sandwiched between the cover body 100 and the post 410. The sealing element 600 can seal the gap between the cover body 100 and the post 410, ensuring good sealing performance of the cell cover.

[0029] See also Figure 4 , Figure 5 , Figure 10 and Figure 11 Along the first direction, the height H of the elastic buffer 220 protruding from the end face of the plastic body 210 on the side opposite to the electrode assembly is 0.04mm≤H≤0.08mm. For example, the value of H can be 0.04mm, 0.05mm, 0.06mm, 0.07mm, or 0.08mm, etc. By limiting the value of H within the above range, the elastic buffer 220 can provide good protection for the plastic body 210 during riveting, preventing damage or cracking of the first plastic part 200. Of course, the value of H should not be too large, otherwise the size of the elastic buffer 220 that needs to be compressed will be large, the riveting force required when riveting the electrode post 400 and the connecting block body 310 will be too large, the processing difficulty of the riveting process will increase, and the processing efficiency will be reduced.

[0030] See Figures 7-9 In this embodiment, multiple mounting slots 212 are provided, and these multiple mounting slots 212 are respectively arranged on both sides of the second mounting hole 211 along a third direction on the plastic body 210. Mounting slots 212 located on the same side of the second mounting hole 211 along a third direction form a slot group. Multiple mounting slots 212 in each slot group are arranged circumferentially at intervals around the second mounting hole 211, and the two slot groups are symmetrical about the second mounting hole 211. Elastic buffer members 220 correspond one-to-one with the mounting slots 212, and each mounting slot 212 contains one elastic buffer member 220.

[0031] In a cross-section perpendicular to the first direction, the cross-sectional area of ​​each mounting groove 212 is S1, and the cross-sectional area of ​​the second mounting hole 211 is S2; the number of all mounting grooves 212 is N, and the relationship between N, S1, and S2 satisfies: 0.25 ≤ (N×S1) / S2 ≤ 0.7. For example, the value of (N×S1) / S2 can be 0.25, 0.3, 0.4, 0.5, 0.6, or 0.7, etc. By limiting the value of (N×S1) / S2 to the above range, the elastic buffer 220 can provide good support and protection for the plastic body 210 located circumferentially in the second mounting hole 211, preventing the first plastic part 200 from cracking or deforming. It is important to note that the value of (N×S1) / S2 should not be too small. Otherwise, the total area of ​​the elastic buffer 220 supporting the connecting block body 310 will be insufficient, resulting in inadequate protection of the plastic body 210 during riveting. This could easily lead to localized damage or cracking of the first plastic part 200. Conversely, the value of (N×S1) / S2 should not be too large either. Excessive number or size of the mounting grooves 212 on the plastic body 210 will reduce the mechanical strength of the plastic body 210, increasing the risk of damage or cracking under riveting pressure.

[0032] See Figure 6 ,as well as Figures 12-17 The connecting block body 310 and the protective insert 320 can be connected using the following detachable mounting structure, which facilitates replacement while reducing the weight and cost of the parts. Specifically, the connecting block body 310 has a slot 312 on each side along the second direction, and there are two protective inserts 320, each inserted into a corresponding slot 312 along the first direction. This plug-in installation method makes assembly and disassembly easy. Moreover, with protective inserts 320 on both sides of the width direction (i.e., the second direction) of the connecting block body 310, the mechanical strength of the opposite sides of the connecting block body 310 along the second direction is greatly improved. It is less likely to deform or collapse when riveted with the pole post 400, and it can withstand greater riveting pressure, maintaining the good shape and flat surface of the connecting block body 310, which facilitates the connection with the battery cell in series and parallel connection.

[0033] Optionally, the protective insert 320 has a limiting boss 321 on one side facing the connecting block body 310 along the second direction. The limiting boss 321 is located at the end of the protective insert 320 along the third direction and extends outward along the third direction. A first limiting part 3121 is provided at the corresponding position of the slot 312. The limiting boss 321 and the first limiting part 3121 cooperate to limit the displacement of the protective insert 320 along the second direction and ensure the stability of the protective insert 320 assembled on the connecting block body 310. Further, the limiting boss 321 includes a first limiting inclined surface 3211. The angle between the first limiting inclined surface 3211 and the side of the connecting block body 310 opposite to each other along the second direction is α. The value of α is in the range of 10°≤α≤60°. For example, the value of α can be 10°, 20°, 30°, 40°, 50° or 60°, etc. By limiting the value of α within the above range, on the one hand, the slot 312 is easy to form, and on the other hand, the first limiting part 3121 has a good limiting effect on the protective insert 320. The protective insert 320 will not move relative to the connecting block body 310 in the second direction, and the positioning effect is good.

[0034] Furthermore, the connecting block body 310 is provided with a material feeding groove 313 on each side along the second direction. The material feeding groove 313 communicates with the slot 312. The protective insert 320 is provided with multiple support platforms 322 on the side facing the connecting block body 310 along the second direction. The multiple support platforms 322 are located in the middle of the protective insert 320 along the third direction, and two adjacent support platforms 322 are spaced apart along the third direction. At least a portion of the multiple support platforms 322 extends into the material feeding groove 313. When the pole post 400 is riveted to the connecting block body 310, the two sides of the support platforms 322 along the second direction can provide reliable support to the groove wall of the material feeding groove 313 opposite to the material feeding groove 313 along the second direction and the main body of the protective insert 320, making it less likely for the connecting block body 310 to deform or crack. At the same time, a material feeding space 3221 is formed between two adjacent support platforms 322. If the connecting block body 310 deforms, it can provide space for overflow, preventing the connecting block body 310 from deforming on both sides of the second direction and excessively squeezing the first plastic part 200, thus protecting the first plastic part 200 from damage or cracking.

[0035] See also Figure 14 and Figure 16 Along the third direction, the dimension of the third mounting hole 311 is L1, and the length of the main body of the protective insert 320 is L2. The relationship between L1 and L2 satisfies: 4mm ≤ L2 - L1 ≤ 10mm. For example, the value of L2 - L1 can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm, etc. By restricting L1 and L2 to satisfy the above relationship, the protective insert 320 can reliably strengthen the connecting block body 310, preventing deformation of the connecting block body 310 during riveting. If the value of L2 - L1 is too small, the dimension of the protective insert 320 along the third direction is too small, and it cannot provide reliable support for the connecting block body 310 circumferentially around the third mounting hole 311. The connecting block body 310 is prone to deformation or cracking under large riveting pressure. Of course, the value of L2 - L1 should not be too large either; otherwise, if the dimension of the slot 312 opened on the connecting block body 310 along the third direction is too large, it will also reduce the mechanical strength of the connecting block body 310 itself and reduce its reliability.

[0036] Along the third direction, the length of the connecting block body 310 is A, and the relationship between L2 and A satisfies: 0.25 ≤ L2 / A ≤ 0.45. For example, the value of L2 / A can be 0.25, 0.3, 0.35, 0.4, or 0.45, etc. By limiting the value of L2 / A within the above range, the connecting block body 310 still has high structural strength after the slot 312 is opened, and it is not easy to deform or crack during riveting. If the value of L2 / A is too small, the size of the protective insert 320 that can be accommodated along the third direction will be too small, and the structural strengthening effect on the connecting block body 310 will not be obvious. Of course, the value of L2 / A should not be too large either, otherwise the size of the feed groove 313 opened on the connecting block body 310 along the third direction will be too large, which will reduce the mechanical strength of the connecting block body 310 itself and reduce its reliability.

[0037] Furthermore, along the third direction, the dimension of the feed groove 313 is L3, and the relationship between L2 and L3 satisfies: 0.25≤L3 / L2≤0.5. For example, the value of L3 / L2 can be 0.25, 0.3, 0.35, 0.4, 0.45, or 0.5, etc. By limiting the value of L3 / L2 to the above range, the contact area between the support platform 322 of the protective insert 320 and the connecting block body 310 is larger, providing reliable reinforcement, while providing a sufficiently large feed space 3221. If the value of L3 / L2 is too small, the arrangement range of the support platform 322 along the third direction is small, which cannot provide reliable support for the connecting block body 310 circumferentially around the third mounting hole 311, and the feed space 3221 is small. The connecting block body 310 is prone to deformation when subjected to large riveting pressure, which in turn will excessively compress the first plastic part 200, easily causing the first plastic part 200 to burst. Of course, the value of L3 / L2 should not be too large. Otherwise, if the size of the feed groove 313 opened on the connecting block body 310 along the third direction is too large, it will reduce the mechanical strength of the connecting block body 310 itself and reduce its reliability.

[0038] See also Figure 13 and Figure 15The two outermost support platforms 322 are provided with a second limiting inclined surface 3222 on the side of the opposite wall of the feed chute 313 along the third direction. The feed chute 313 is provided with a second limiting part 3131 along the opposite wall of the feed chute 313 along the third direction. The second limiting inclined surface 3222 and the second limiting part 3131 cooperate to limit the displacement of the protective insert 320 along the second direction, further ensuring the stability of the protective insert 320 assembled on the connecting block body 310. Optionally, the included angle between the second limiting inclined surface 3222 and the opposite wall of the feed chute 313 along the second direction is β, and the value of β is in the range of 10°≤β≤80°. For example, the value of β can be 10°, 20°, 30°, 40°, 50° or 60°, etc. By limiting the value of β within the above range, on the one hand, it ensures that the feed groove 313 is easy to form, and on the other hand, it ensures that the second limiting part 3131 has a good limiting effect on the protective insert 320. The protective insert 320 will not move relative to the connecting block body 310 in the second direction, and the positioning effect is good.

[0039] See also Figure 6 , Figure 13 and Figure 17 Along the second direction, in this embodiment, the size of the third mounting hole 311 on the connecting block body 310 is W1, and the distance between the end faces of the two protective inserts 320 facing away from each other is B. The relationship between W1 and B satisfies: 0.25≤W1 / B≤0.55. For example, the value of W1 / B can be 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, or 0.55, etc. By limiting the value of W1 / B to the above range, it is ensured that the side of the connecting block body 310 in the width direction (i.e., the second direction) has sufficient mechanical strength after the third mounting hole 311 is opened, and it is not easy to deform, crack, or other problems.

[0040] Along the second direction, the distance between the opposite walls of the two feed grooves 313 along the second direction is W2, and the distance between the opposite walls of the two slots 312 along the second direction is W3. The relationship between W2 and W3 satisfies: 1mm ≤ W3 - W2 ≤ 6mm. For example, the value of W3 - W2 can be 1mm, 2mm, 3mm, 4mm, 5mm, or 6mm, etc. By limiting the value of W3 - W2 to the above range, the size of the support platform 322 along the second direction is ensured to be relatively large, so that it can stably cooperate with the feed grooves 313, the protective insert 320 is not easy to shift, and the fixing effect is good. Of course, the value of W3 - W2 should not be too large, otherwise the size of the support platform 322 along the second direction will be too large, which will increase the weight and cost of the protective insert 320, and the opening size of the feed grooves 313 on the connecting block body 310 will be too large, which is not conducive to improving the structural strength of the connecting block body 310.

[0041] Furthermore, in this embodiment, the first plastic part 200 also includes a limiting plate 230. The limiting plate 230 is disposed circumferentially on the plastic part body 210 and extends away from the electrode assembly. The limiting plate 230 and the plastic part body 210 form a receiving groove 231, and the connecting block 300 is disposed within the receiving groove 231. A limiting step 232 is provided on the inner wall of the limiting plate 230, and a step portion 314 is provided circumferentially on the connecting block body 310. The step portion 314 cooperates with the limiting step 232 to achieve precise positioning between the first plastic part 200 and the connecting block 300, resulting in a high assembly yield. Optionally, the step portion 314 includes a first step surface 3141 perpendicular to the first direction and a second step surface 3142 parallel to the first direction. Along the first direction, the height of the step portion 314 is the same as the depth of the slot 312, and the first step surface 3141 is coplanar with the bottom of the slot 312, making the overall appearance of the connecting block 300 regular and without protruding parts.

[0042] Along the first direction, the height of the connecting block body 310 is T1, and the depth of the slot 312 is T2, which means the height of the protective insert 320 along the first direction is T2. The relationship between T1 and T2 satisfies: 0.5mm ≤ T1 - T2 ≤ 1.5mm. For example, the value of T1 - T2 can be 0.5mm, 0.6mm, 0.8mm, 1.0mm, 1.2mm, 1.4mm, or 1.5mm, etc. By limiting the value of T1 - T2 to meet the above dimensional constraints, the mechanical strength of the protective insert 320 itself is ensured to be high. After the protective insert 320 is installed in the slot 312, it can greatly improve the structural strength of the connecting block body 310, so that the connecting block 300 can withstand greater riveting pressure without deformation or cracking, and has high reliability.

[0043] This embodiment also provides a battery cell, including the aforementioned battery cell cover. The battery cell cover exhibits a high yield rate during assembly; during riveting, neither the first plastic part 200 nor the connecting block 300 shows any abnormalities in shape, size, or appearance. The first plastic part 200 has good insulation performance, preventing cracking or damage that could lead to insulation failure. The connecting block 300 has good flatness after riveting, resulting in a high yield rate and high welding efficiency when welded to the battery cell. Furthermore, the terminal post 400 has a large cross-sectional area, meeting the requirements for high-capacity, high-rate fast charging of the battery cell.

[0044] The following uses samples from specific implementation cases to verify the relevant dimensional design of the above-mentioned cell cover plate. See Table 1 for details.

[0045] Table 1 As can be seen from the above results, the range of values ​​for parameters H, (N×S1) / S2, L2-L1, L3 / L2, W3-W2, W1 / B, T2, T1-T2, L2 / A, α, and β in Examples 1 to 6 meets their corresponding size limitations. When the pole post 400 is riveted to the connecting block 300, neither the first plastic part 200 nor the connecting block 300 cracks, and the connecting block 300 does not experience any bulging or deformation. The cell cover has good resistance to thrust and torque, and excellent current carrying capacity, indicating that the cell cover product is of good quality.

[0046] In Comparative Example 1, the value of parameter H is less than the minimum value of 0.04mm≤H≤0.08mm. At this time, the height of the elastic buffer 220 protruding from the end face of the plastic body 210 away from the electrode group along the first direction is insufficient, and it cannot provide effective and reliable protection for the plastic body 210. After riveting, the first plastic part 200 is damaged or cracked, and the battery cell cover product is defective.

[0047] In Comparative Example 2, the value of parameter H is greater than the maximum value of 0.04mm≤H≤0.08mm. At this time, the height of the elastic buffer 220 protruding from the end face of the plastic body 210 away from the electrode group along the first direction is too large, the compressive force of the elastic buffer 220 is too large, the riveting pressure required when riveting the electrode post 400 and the connecting block 300 is too large, the riveting difficulty increases, the cost increases, the processing efficiency decreases, and the battery cell cover plate product is defective.

[0048] In Comparative Example 3, the value of parameter (N×S1) / S2 is less than the minimum value of 0.25≤(N×S1) / S2≤0.7. At this time, the contact area between the elastic buffer 220 and the connecting block body 310 is insufficient, and it cannot provide reliable protection for the first plastic part 200 during riveting. After riveting, the first plastic part 200 is damaged or cracked, resulting in a defective battery cell cover product.

[0049] In Comparative Example 4, the value of parameter (N×S1) / S2 is greater than the maximum value of 0.25≤(N×S1) / S2≤0.7. At this time, the contact area between the elastic buffer 220 and the connecting block body 310 is sufficient, but the increase in the number or size of the mounting grooves 212 has an adverse effect on the mechanical strength of the plastic body 210. After riveting, the first plastic part 200 is damaged or cracked, resulting in a defective battery cell cover product.

[0050] In Comparative Example 5, the value of parameter W3-W2 is less than the minimum value of 1mm ≤ W3-W2 ≤ 6mm. At this time, the size of the support platform 322 along the second direction is too small, the feed groove 313 is not easy to process and form, and the connection strength between the support platform 322 and the feed groove 313 is reduced. The protective insert 320 is prone to displacement, the riveting yield is reduced, and the mechanical strength of the support platform 322 itself is insufficient, which cannot provide effective and reliable support for the connecting block body 310. The connecting block 300 has deformation problems, and in severe cases, it will crack, resulting in defective battery cell cover products.

[0051] In Comparative Example 6, the value of parameter W3-W2 is greater than the maximum value of 1mm≤W3-W2≤6mm. At this time, the size of the support platform 322 along the second direction is too large, the feed groove 313 has a significant impact on the mechanical strength of the connecting block body 310 itself, the connecting block 300 has deformation or cracking problems after riveting, and the weight and cost of the protective insert 320 increase, resulting in defective battery cell cover products.

[0052] Taking all factors into consideration, when the size design of the cell cover plate meets the above size requirements, it can ensure a high yield rate of riveting between the terminal post 400 and the connecting block 300, and both the first plastic part 200 and the connecting block 300 remain intact without deformation or cracking. The cell cover plate has good resistance to thrust and torque and excellent current carrying capacity.

[0053] 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: A cover plate body, wherein the cover plate body is provided with a first mounting hole; A first plastic component is disposed on the side of the cover plate body away from the electrode group along a first direction. The first plastic component includes a plastic component body and an elastic buffer. The plastic component body is provided with a second mounting hole and a mounting groove. The mounting groove is located circumferentially to the second mounting hole. The opening of the mounting groove faces the side away from the cover plate body. The bottom of the mounting groove is provided with a through hole penetrating the plastic component body. The elastic buffer is embedded in the mounting groove. The first direction is the thickness direction of the battery cell cover plate. A connecting block is disposed on the side of the first plastic part away from the cover plate body along a first direction. The connecting block includes a connecting block body and a protective insert. The connecting block body is provided with a third mounting hole. The protective insert is disposed on the side of the connecting block body along a second direction and is located on the side of the connecting block body close to the electrode group along the first direction. The protective insert is adjacent to the third mounting hole along the second direction, which is the width direction of the cell cover plate. The pole post passes sequentially through the first mounting hole, the second mounting hole, and the third mounting hole from the side where the pole group is located along the first direction and is then riveted to the body of the connecting block.

2. The cell cover plate according to claim 1, characterized in that, The pole post includes a column portion, which passes through the first mounting hole, the second mounting hole, and the third mounting hole; in a cross section perpendicular to the first direction, the cross section of the column portion is waist-shaped, and the cross sections of the first mounting hole, the second mounting hole, and the third mounting hole are also waist-shaped.

3. The cell cover plate according to claim 2, characterized in that, Along the first direction, the height of the elastic buffer protruding from the end face of the plastic body on the side opposite to the pole group is H; The value range of H is: 0.04mm≤H≤0.08mm.

4. The cell cover plate according to claim 2, characterized in that, The mounting slots are provided in multiple ways, and the multiple mounting slots are respectively arranged on both sides of the second mounting hole along a third direction, the third direction being the length direction of the cell cover plate; the mounting slots located on the same side of the second mounting hole along the third direction form a slot group, and the multiple mounting slots in each slot group are arranged at circumferential intervals in the second mounting hole; the elastic buffer corresponds to each mounting slot; In a cross-section perpendicular to the first direction, the cross-sectional area of ​​each of the mounting slots is S1, and the cross-sectional area of ​​the second mounting hole is S2; the number of all the mounting slots is N. The relationship between N, S1 and S2 satisfies: 0.25≤(N×S1) / S2≤0.

7.

5. The cell cover plate according to claim 2, characterized in that, The connecting block body is provided with a slot on each side along the second direction, and two protective inserts are provided, each of which is inserted into one of the slots along the first direction. The protective insert has a limiting boss on one side facing the connecting block body along the second direction. The limiting boss is located at the end of the protective insert along the third direction and extends outward along the third direction. The corresponding position of the slot has a first limiting part. The limiting boss cooperates with the first limiting part to limit the displacement of the protective insert along the second direction.

6. The cell cover plate according to claim 5, characterized in that, The connecting block body is provided with a material feeding groove on each side along the second direction. The material feeding groove is connected to the slot. The protective insert is provided with a plurality of support platforms on one side of the connecting block body along the second direction. The plurality of support platforms are located in the middle of the protective insert along the third direction, and two adjacent support platforms are spaced apart along the third direction. At least a portion of the plurality of support platforms extends into the material feeding groove. Along the third direction, the size of the third mounting hole is L1, the length of the main body of the protective insert is L2, the size of the material feeding groove is L3, and the length of the connecting block body is A; The relationship between L1 and L2 satisfies: 4mm≤L2-L1≤10mm; The relationship between L2 and L3 satisfies: 0.25 ≤ L3 / L2 ≤ 0.5; The relationship between L2 and A satisfies: 0.25 ≤ L2 / A ≤ 0.

45.

7. The cell cover plate according to claim 6, characterized in that, The limiting boss includes a first limiting inclined surface, and the angle between the first limiting inclined surface and the side of the connecting block body opposite to each other along the second direction is α; The range of values ​​for α is: 10°≤α≤60°; And / or, in the two outermost support platforms, a second limiting inclined surface is provided on the side of the opposite wall of the material feeding trough along a third direction, and a second limiting part is provided on the opposite wall of the material feeding trough along a third direction, and the second limiting inclined surface cooperates with the second limiting part; wherein, the included angle between the second limiting inclined surface and the opposite wall of the material feeding trough along a second direction is β; The range of β is: 10°≤β≤80°.

8. The cell cover plate according to claim 6, characterized in that, Along the second direction, the size of the third mounting hole is W1, the distance between the opposite walls of the two material feeding grooves along the second direction is W2, the distance between the opposite walls of the two slots along the second direction is W3, and the distance between the end faces of the two protective inserts facing away from each other is B. The relationship between W1 and B satisfies: 0.25 ≤ W1 / B ≤ 0.55; The relationship between W2 and W3 satisfies: 1mm≤W3-W2≤6mm.

9. The cell cover plate according to claim 5, characterized in that, The connecting block body has a stepped portion around its circumference. The stepped portion includes a first stepped surface perpendicular to the first direction and a second stepped surface parallel to the first direction. Along the first direction, the height of the stepped portion is the same as the depth of the slot, and the first stepped surface is coplanar with the bottom of the slot. Along the first direction, the height of the connecting block body is T1, and the depth of the slot is T2; The relationship between T1 and T2 satisfies: 0.5mm≤T1-T2≤1.5mm.

10. A battery cell, characterized in that, Includes the cell cover plate according to any one of claims 1-9.

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