Sealing rings, cover plates, battery cells and battery packs

Abstract

This invention relates to the field of battery technology and discloses a sealing ring, a cover plate, a battery cell, and a battery pack. In this invention, the sealing ring is fitted onto the cylindrical portion of the terminal post. Before installation, the central through-hole of the sealing ring is a circular hole, which does not require directional differentiation, facilitating the positioning and assembly of the sealing ring. 1 < (b+a) / a ≤ 10, meaning the length of the cylindrical portion is greater than its width, and the length of the cylindrical portion is less than ten times its width. This design prevents the cylindrical portion from becoming excessively long. After the sealing ring is opened through the circular through-hole, the corresponding length of the opened sealing ring is not excessive. After being fitted onto the cylindrical portion, the sealing ring can quickly elastically recover and wrap around the cylindrical portion, effectively preventing the sealing ring from twisting or warping. While facilitating the positioning and installation of the sealing ring, it effectively ensures the sealing effect of the sealing ring, thereby preventing air leakage from the cover plate and ensuring the sealing performance of the cover plate.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to a sealing ring, a cover plate, a battery cell, and a battery pack. Background Technology

[0002] The cover plate using the pole post riveting fixing method includes a riveting block, a first insulating component, a cover plate body, a second insulating component, a pole post, and a sealing ring. The cover plate body has mounting holes. The pole post includes a base plate and a post body. The post body passes through the mounting holes and is riveted to the riveting block. The sealing ring has a through hole in the middle. The sealing ring includes a horizontally extending horizontal part and a vertically extending vertical part. The through hole is fitted onto the post body. The side of the horizontal part facing the base plate is attached to the base plate to form a seal between the cover plate body and the base plate. The inner wall of the vertical part is attached to the post body to form a seal between the cover plate body and the post body.

[0003] Existing cylindrical sections are generally cylindrical. For battery cells with narrow, elongated cover plates and high current carrying capacity, the narrow width of the cover plate prevents increasing the diameter of the cylindrical section from improving its current carrying capacity. Therefore, the only solution is to increase the length of the cylindrical section, resulting in a narrow, elongated shape. This non-circular cross-section of the cylindrical section leads to a non-circular inner hole in the mating sealing ring. This makes the sealing ring installation directional, difficult to position during assembly, and challenging. Furthermore, after the sealing ring is fitted onto the cylindrical section, it is prone to twisting and misalignment, affecting its sealing performance and causing air leakage from the cover plate. Summary of the Invention

[0004] In view of this, the present invention provides a sealing ring, a cover plate, a battery cell, and a battery pack to solve the problem in the prior art that the sealing ring, which mates with a non-circular cylindrical part, is prone to twisting and skewing after assembly, affecting the sealing performance of the cover plate.

[0005] In a first aspect, the present invention provides a sealing ring suitable for use in a cover plate. The cover plate includes a cover plate body and an electrode post. The electrode post includes a base plate and a column portion disposed on the base plate. The long side of the column portion extends in the same direction as the long side of the cover plate, and the length of the column portion is greater than the width of the column portion. The cross-section of the column portion near one end of the base plate includes a rectangular smooth central region and semicircular arcs disposed at both ends of the smooth central region. The diameter of the semicircular arcs is equal to the width of the smooth central region, the diameter of the semicircular arcs is a, and the length of the smooth central region extending along the long side of the cover plate is b. The sealing ring includes:

[0006] The cylindrical part comprises a parallel portion and a vertical portion disposed on the parallel portion, wherein the parallel portion and the vertical portion are provided with a through hole, the through hole being a circular hole with a circumference equal to the circumference of the cylindrical portion; the through hole is adapted to be fitted onto the cylindrical portion, the side of the parallel portion facing the base plate is adapted to be attached to the base plate, and the wall of the through hole is adapted to be attached to the outer peripheral wall of the cylindrical portion; the radius of the through hole is r, r = (2b + πa) / 2π, 1 < (b + a) / a ≤ 10, and the units of a, b, and r are all mm.

[0007] Beneficial effects: When using this sealing ring, it is fitted onto the cylindrical part of the pole. Before installation, the central through hole of the sealing ring is a round hole, and the direction of the round hole does not need to be distinguished. During installation, the clamps can be used to open the sealing ring from any direction to both sides and then fit it onto the cylindrical part. The two ends of the sealed ring that are opened correspond to the semi-circular arc area of ​​the cylindrical part. After the clamps are released, the two ends of the sealing ring along the length direction are positioned and fitted onto the cylindrical part at the semi-circular arc area. The sealing ring can then be completely fitted and wrapped around the cylindrical part, making the positioning and assembly of the sealing ring convenient. The circumference of the through hole of the sealing ring is equal to the circumference of the outer wall of the cylindrical part. The circumference of the outer wall of the cylindrical part is 2b+πa, and the circumference of the through hole is 2πr, so r=(2b+πa) / 2π; b+a is the total length of the cylindrical part, and a is the width of the cylindrical part. 1<(b+a) / a≤10, that is, the length of the cylindrical part is greater than its width, and the length of the cylindrical part is less than ten times the width of the cylindrical part. If the length-to-width ratio of the column is too large, the column will be too long. Consequently, the sealing ring needs to be stretched too far to both ends. After being fitted onto the column, the sealing ring is prone to twisting and misalignment, preventing the parallel portion from fitting snugly against the base plate or the vertical portion from fully fitting against the column's sidewalls. A setting of 1 < (b+a) / a ≤ 10 prevents the column from becoming excessively long. After the sealing ring is stretched through the circular through-hole, the stretched length is not excessive. Once fitted onto the column, the sealing ring can quickly elastically recover and wrap around it, effectively preventing twisting and misalignment. This design facilitates sealing ring positioning and installation while ensuring a good seal, preventing air leakage from the cover and guaranteeing its airtightness.

[0008] In one alternative implementation, 1 < (b + a) / a ≤ 3.

[0009] Beneficial effects: This design further optimizes the length-to-width ratio of the column section, reduces the length of the sealing ring that needs to be stretched, and allows the sealing ring to be fitted onto the column section after slight stretching. This prevents the sealing ring from twisting or skewing, improves the fit between the parallel section and the base plate, and between the vertical section and the column section. While facilitating the positioning and installation of the sealing ring, it further ensures the sealing effect of the sealing ring and improves the sealing performance of the cover plate. Simultaneously, 1 < (b+a) / a ≤ 3, preventing the column section from becoming too long and affecting its strength, and ensuring the upper limit of the length-to-width ratio of the column section, thereby guaranteeing the strength of both the column section and the pole.

[0010] In one alternative embodiment, the wall thickness of the vertical portion along the radial direction of the sealing ring is c, where 0.5 mm ≤ c ≤ 1 mm.

[0011] Beneficial effects: 0.5mm≤c≤1mm ensures a minimum vertical wall thickness, facilitating vulcanization molding of the column part. It also ensures the consistency of the vertical wall thickness around the sealing ring, allowing the vertical parts to effectively fit onto the column part and guaranteeing a sealing effect. This, in turn, ensures the sealing effect of the cover plate. At the same time, it avoids excessive vertical wall thickness, which would occupy too much space and increase costs.

[0012] In one alternative embodiment, the thickness of the parallel portion is d, where 0.7 mm ≤ d ≤ 1.5 mm.

[0013] Beneficial effects: 0.7mm≤d≤1.5mm, which can ensure the safe distance between the cover plate body and the base plate, and at the same time ensure the compression of the parallel part, thereby ensuring the insulation protection and sealing effect of the parallel part on the base plate and the cover plate body; at the same time, it can avoid the parallel part being too thick and occupying too much space, thus avoiding increased costs.

[0014] In one alternative embodiment, the radial width of the parallel portion is e, where 1.5 mm ≤ e ≤ 3 mm.

[0015] Secondly, the present invention also provides a cover plate, comprising:

[0016] The cover plate body is provided with mounting holes;

[0017] The pole includes a base plate and a column portion disposed on the base plate. The long side of the column portion extends in the same direction as the long side of the cover plate, and the length of the column portion is greater than the width of the column portion. The cross-section of the column portion near the end of the base plate includes a rectangular smooth area in the middle and semi-circular arcs disposed at both ends of the smooth area in the middle. The diameter of the semi-circular arcs is equal to the width of the smooth area in the middle. The diameter of the semi-circular arcs is a, and the length of the smooth area in the middle along the long side of the cover plate is b.

[0018] In any of the above-mentioned sealing rings, the through hole is fitted onto the cylindrical part, the parallel part is attached to the base plate, and the wall of the through hole is attached to the outer peripheral wall of the cylindrical part; the radius of the through hole is r, r = (2b + πa) / 2π, 1 < (b + a) / a ≤ 10. The cover plate includes the sealing ring and has the same technical effect as the sealing ring, which will not be described in detail here.

[0019] In one optional embodiment, the side of the parallel portion facing the cover plate body abuts against the cover plate body, and the compression amount of the parallel portion at the point where it mates with the cover plate body is f, where 10% ≤ f / d ≤ 50%, and the units of f and d are both mm.

[0020] Beneficial effects: This design ensures that the parallel section has sufficient compression ratio, effectively guaranteeing the seal between the base plate and the cover plate body; at the same time, it prevents excessive compression ratio at the parallel section from damaging the sealing ring, thus ensuring the seal of the parallel section.

[0021] In one optional embodiment, a first insulating member is further included. The first insulating member is disposed on the outer surface of the cover plate body. The first insulating member has a clearance hole for the column portion to pass through. The clearance hole is located inside the circumferential outer edge of the mounting hole. One end of the vertical portion facing the first insulating member abuts against the first insulating member. The compression amount of the vertical portion at the point of contact with the first insulating member is g, where 0.2mm≤g≤0.5mm.

[0022] Beneficial effects: This design can ensure the sealing between the column and the first insulating component. When there is electrolyte leakage on the outer surface of the cover plate body, it can prevent the electrolyte from entering the column along the gap between the first insulating component and the cover plate body, which helps to improve the safety performance of the cover plate.

[0023] Thirdly, the present invention also provides a battery cell, comprising a housing and a cover plate as described above, wherein the housing has an opening and the cover plate is disposed on the opening. The battery cell includes a sealing ring, which has the same technical effects as the sealing ring, and will not be described in detail here.

[0024] Fourthly, the present invention also provides a battery pack including the aforementioned battery cells. The battery pack includes a sealing ring, which has the same technical effects as the sealing ring, and will not be described in detail here. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a three-dimensional structural diagram of a cover plate according to an embodiment of the present invention;

[0027] Figure 2 for Figure 1 A top view of the sealing ring in the cover plate shown;

[0028] Figure 3 for Figure 1 A three-dimensional structural diagram of the sealing ring in the cover plate shown;

[0029] Figure 4 for Figure 1 A schematic diagram of the three-dimensional structure of the pole in the cover plate shown;

[0030] Figure 5 for Figure 1 A three-dimensional structural diagram showing the mating of the sealing ring and the pole in the cover plate;

[0031] Figure 6 for Figure 1 A cross-sectional view of the sealing ring and the pole in the cover plate shown;

[0032] Figure 7 for Figure 1 A top view of the pole in the cover plate shown;

[0033] Figure 8 for Figure 1 The top view of the cover plate shown;

[0034] Figure 9 for Figure 8 Sectional view along axis AA;

[0035] Figure 10 for Figure 9 A magnified view of part A in the diagram;

[0036] Figure 11 for Figure 1 The exploded view of the cover plate is shown.

[0037] Explanation of reference numerals in the attached figures:

[0038] 1. Sealing ring; 11. Parallel part; 12. Vertical part; 13. Through hole; 2. Cover plate body; 3. Pole post; 31. Base plate; 32. Column part; 321. Smooth central area; 322. Semicircular arc; 4. First insulating component; 5. Second insulating component; 6. Riveting block. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] In related technologies, the cylindrical portion is generally cylindrical. For battery cells with narrow and elongated cover plates and high current carrying capacity, the narrow width of the cover plate makes it impossible to increase the current carrying capacity of the battery cell by increasing the diameter of the cylindrical portion. Therefore, the size of the cylindrical portion must be increased along the length of the cover plate, resulting in a narrow and elongated cylindrical portion. This non-circular cross-section of the cylindrical portion is matched with a non-circular inner hole for the sealing ring. The sealing ring installation is directional; its inner hole has a long side and a wide side, which must correspond to the long and wide sides of the cylindrical portion during installation. During installation, the sealing ring is opened and fitted onto the cylindrical portion using clamps. This process is difficult to position and assemble. After the clamps are released, the sealing ring is prone to misalignment or twisting, preventing it from properly fitting the electrode base plate and / or the cylindrical portion. This affects the sealing performance and leads to air leakage from the cover plate.

[0041] The following is combined with Figures 1 to 11 The following describes embodiments of the present invention.

[0042] According to an embodiment of the present invention, a sealing ring 1 is provided, suitable for use in a cover plate. The cover plate includes a cover plate body 2 and an end post 3. The end post 3 includes a base plate 31 and a column portion 32 disposed on the base plate 31. The long side of the column portion 32 extends in the same direction as the long side of the cover plate, and the length of the column portion 32 is greater than the width of the column portion 32. The cross-section of the column portion 32 near the end of the base plate 31 includes a rectangular central smooth area 321 and semicircular arcs 322 disposed at both ends of the central smooth area 321. The diameter of the semicircular arcs 322 is equal to the width of the central smooth area 321, the diameter of the semicircular arcs 322 is a, and the length of the central smooth area 321 extending along the long side of the cover plate is b.

[0043] The sealing ring 1 includes a parallel part 11 and a vertical part 12 provided on the parallel part 11. The parallel part 11 and the vertical part 12 are provided with a through hole 13 that is connected. The through hole 13 is a circular hole, and the circumference of the circular hole is equal to the circumference of the cylindrical part 32. The through hole 13 is suitable for being fitted onto the cylindrical part 32. The side of the parallel part 11 facing the base plate 31 is suitable for being fitted onto the base plate 31. The hole wall of the through hole 13 is suitable for being fitted onto the outer peripheral wall of the cylindrical part 32. The radius of the through hole 13 is r, r=(2b+πa) / 2π, 1<(b+a) / a≤10, and the units of a, b and r are all mm.

[0044] When using the sealing ring 1 of this structure, it is fitted onto the cylindrical part 32 of the pole post 3. Before installation, the through hole 13 in the middle of the sealing ring 1 is a round hole. The round hole does not need to be distinguished by direction. During installation, the clamps can be used to open the sealing ring 1 from any direction to both sides and then fit it onto the cylindrical part 32. The two ends of the sealing ring 1 that are opened correspond to the semi-circular arc 322 area of ​​the cylindrical part 32. After the clamps are released, the two ends of the sealing ring 1 in the length direction are positioned and fitted onto the cylindrical part 32 in the semi-circular arc 322 area. The sealing ring 1 can then be completely fitted and wrapped around the cylindrical part 32. The positioning and assembly of the sealing ring 1 are convenient. The perimeter of the through hole 13 of the sealing ring 1 is equal to the perimeter of the outer wall of the column part 32. The perimeter of the outer wall of the column part 32 is 2b+πa, and the perimeter of the through hole 13 is 2πr. Therefore, r = (2b+πa) / 2π. b+a is the total length of the column part 32, and a is the width of the column part 32. 1 < (b+a) / a ≤ 10, meaning that the length of the column part 32 is greater than its width, and the length of the column part 32 is less than ten times its width. If the length-to-width ratio of the column part 32 is too large, the length of the column part 32 will be too long. Correspondingly, the sealing ring 1 needs to be stretched longer towards both ends. After the sealing ring 1 is fitted onto the column part 32, it is easy to twist and skew, causing the parallel part 11 to fail to fit with the base plate 31, or the vertical part 12 to fail to fit completely with the side wall of the column part 32. 1 < (b + a) / a ≤ 10. This setting can prevent the length of the column part 32 from being too long. After the sealing ring 1 is opened from the circular through hole 13, the length of the sealing ring 1 that is opened is not too large. After the sealing ring 1 is fitted on the column part 32, it can quickly elastically recover and wrap around the column part 32. This can effectively prevent the sealing ring 1 from twisting or tilting. While facilitating the positioning and installation of the sealing ring 1, it can effectively ensure the sealing effect of the sealing ring 1, thereby preventing the cover plate from leaking air and ensuring the sealing performance of the cover plate.

[0045] In some optional embodiments, 1 < (b+a) / a ≤ 3. This setting can further optimize the aspect ratio of the column portion 32, further reduce the length of the sealing ring 1 that is stretched, and allow the sealing ring 1 to be fitted onto the column portion 32 after being slightly stretched. This prevents the sealing ring 1 from twisting or skewing, which is beneficial for improving the fit between the parallel portion 11 and the base plate 31, as well as the fit between the vertical portion 12 and the column portion 32. While facilitating the positioning and installation of the sealing ring 1, it can further ensure the sealing effect of the sealing ring 1 and further improve the sealing performance of the cover plate. At the same time, 1 < (b+a) / a ≤ 3 can prevent the column portion 32 from being too long and affecting its own strength, and can ensure the upper limit of the aspect ratio of the column portion 32, thereby ensuring the strength of the column portion 32 and the pole 3.

[0046] The design includes pole posts 3 with different values ​​of a, b, and (b+a) / a, and sealing rings 1 corresponding to the circumference of the column portion 32 of different pole posts 3. Before installation, the through hole 13 of the sealing ring 1 is a round hole. The sealing ring 1 is fitted onto the pole post 3, and the fit between the sealing ring 1 and the pole post 3 is observed. The test results are shown in Table 1.

[0047] Table 1

[0048]

[0049] As can be seen from Examples 1 to 6 in Table 1, for the pole post 3 with a column part 32 having a racetrack-shaped cross-section, that is, the middle area of ​​the cross-section of the column part 32 is rectangular and the two ends of the rectangle are semicircles. Before installation, the through hole 13 of the sealing ring 1 is a round hole. The perimeter of the through hole 13 of the sealing ring 1 is equal to the perimeter of the column part 32. When the length and width dimensions of the column part 32 satisfy 1 < (b + a) / a ≤ 10, after the sealing ring 1 is installed, the vertical part 12 of the sealing ring 1 fits well with the column part 32 of the pole post 3, and the parallel part 11 of the sealing ring 1 fits well with the base plate 31 of the pole post 3. The sealing ring 1 is not twisted or skewed, which can effectively ensure the sealing performance of the sealing ring 1. As shown in Comparative Example 1, when (b+a) / a = 10.5, the length of the column portion 32 is relatively long, and the parallel portion 11 along the long side of the column portion 32 is twisted. The parallel portion 11 in this area does not fit snugly against the base plate 31 of the pole post 3. The defect rate of the sealing ring 1 after installation is 1.2%, indicating that the sealing ring 1 is prone to sealing failure. As shown in Comparative Example 2, when (b+a) / a = 15, the length of the column portion 32 is also relatively long, and the length-to-width ratio of the column portion 32 exceeds the upper limit by a significant margin. The parallel portion 11 along the long side of the column portion 32 is twisted, and the parallel portion 11 in this area does not fit snugly against the base plate 31 of the pole post 3. The defect rate of the sealing ring 1 after installation is 3.6%, indicating a relatively high installation failure rate and that the sealing ring 1 is prone to sealing failure.

[0050] like Figure 3As shown, in some embodiments, the wall thickness of the vertical part 12 along the radial direction of the sealing ring 1 is c, where 0.5mm≤c≤1mm. This setting ensures the minimum wall thickness of the vertical part 12. After the cover plate is assembled, the vertical part 12 is isolated between the hole wall of the mounting hole of the cover plate body 2 and the column part 32, where c≥0.5mm. This prevents the wall thickness of the vertical part 12 from being too small and affecting its insulation protection effect, and prevents the vertical part 12 from being broken down under the action of a strong electric field. Thus, the insulation protection and sealing effect between the hole wall of the mounting hole of the cover plate body 2 and the column part 32 can be guaranteed. Furthermore, since the sealing ring 1 is formed by vulcanization, if the wall thickness of the vertical portion 12 is small, it is difficult to ensure the consistency of the wall thickness around the circumference of the sealing ring 1 during molding. This can easily lead to inconsistent wall thicknesses around the circumference of the sealing ring 1, meaning that the wall thickness of the vertical portion 12 is thinner at some locations and thicker at others. This makes it difficult to ensure that the vertical portion 12 of the sealing ring 1 effectively fits onto the column portion 32, affecting the sealing performance of the cover plate. A minimum wall thickness of c ≥ 0.5 mm ensures the minimum vertical wall thickness, facilitates the vulcanization molding of the column portion 32, and guarantees the consistency of the wall thickness of the vertical portion 12 around the circumference of the sealing ring 1. This ensures that the vertical portion 12 effectively fits onto the column portion 32, guaranteeing the sealing effect of the vertical portion 12 and thus ensuring the sealing effect of the cover plate. Simultaneously, it avoids excessively thick vertical portions 12 that would occupy too much space and increase costs.

[0051] After the sealing ring 1, cover plate body 2, and pole post 3 are assembled into a cover plate, the base plate 31 is located on the inner side of the inner surface of the cover plate body 2. A second insulating element 5 is also provided between the cover plate body 2 and the base plate 31. The second insulating element 5 plays an insulating and protective role between the base plate 31 and the cover plate body 2. To prevent the second insulating element 5 between the base plate 31 and the cover plate body 2 from being punctured, the distance between the facing sides of the cover plate body 2 and the base plate 31 needs to be greater than or equal to 0.5 mm. The two sides of the parallel part 11 abut against the inner wall surface of the cover plate body 2 and the outer wall surface of the base plate 31, respectively. Therefore, the thickness of the parallel part 11 needs to be... The thickness of the parallel part 11 is greater than 0.5mm. After installation, the parallel part 11 will be compressed to a certain extent in its thickness direction. The thickness of the parallel part 11 before compression is d, which is 0.7mm≤d≤1.5mm. This can ensure the safe distance between the cover plate body 2 and the base plate 31, and at the same time ensure the compression of the parallel part 11. This can ensure the insulation protection and sealing effect of the parallel part 11 on the base plate 31 and the cover plate body 2. At the same time, it can avoid the parallel part 11 being too thick and occupying too much space, thus avoiding the increase in cost.

[0052] like Figure 2 and Figure 3As shown, the radial width of the parallel portion 11 is e. The inner wall of the parallel portion 11 is flush with the inner wall of the vertical portion 12. The wall thickness of the vertical portion 12 is c≥0.5mm. The outer diameter of the parallel portion 11 is larger than the outer diameter of the vertical portion 12, so that the parallel portion 11 forms a step on the outer periphery of the vertical portion 12, so that the two sides of the step abut against the cover plate body 2 and the bottom plate 31 respectively, thereby providing insulation and sealing between the bottom plate 31 and the cover plate body 2. The parallel portion 11 needs to form a step on the outer periphery of the vertical portion 12. Therefore, the radial width of the parallel portion 11 needs to be greater than the wall thickness of the vertical portion 12. In addition, considering assembly tolerances and compression allowances, in some embodiments, the radial width e of the parallel portion 11 satisfies 1.5mm≤e≤3mm. This setting can ensure the insulation and sealing performance between the cover plate body 2 and the bottom plate 31; at the same time, it can avoid design redundancy caused by an excessively large e, and avoid the parallel portion 11 occupying too much space and increasing costs.

[0053] According to an embodiment of the present invention, another aspect provides a cover plate, including a cover plate body 2, a pole post 3, and a sealing ring 1.

[0054] The cover plate body 2 is provided with mounting holes; the pole post 3 includes a base plate 31 and a column part 32 provided on the base plate 31. The long side of the column part 32 extends in the same direction as the long side of the cover plate and the length of the column part 32 is greater than the width of the column part 32; the cross section of the column part 32 near the end of the base plate 31 includes a rectangular central smooth area 321 and semi-circular arcs 322 provided at both ends of the central smooth area 321. The diameter of the semi-circular arcs 322 is equal to the width of the central smooth area 321, the diameter of the semi-circular arcs 322 is a, and the length of the central smooth area 321 extending along the long side of the cover plate is b; the through hole 13 is sleeved on the column part 32, the parallel part 11 is attached to the base plate 31, and the hole wall of the through hole 13 is attached to the outer peripheral wall of the column part 32; the radius of the through hole 13 is r, r=(2b+πa) / 2π, 1<(b+a) / a≤10.

[0055] Before installation, the sealing ring 1 on the cover plate has a round hole 13 in the middle. The round hole does not need to be distinguished by direction. During installation, the clamps can be used to open the sealing ring 1 from any direction to both sides and then put it on the column part 32. The two ends of the sealing ring 1 that are opened correspond to the semi-circular arc 322 area of ​​the column part 32. After the clamps are released, the two ends of the sealing ring 1 in the length direction are positioned and put on the column part 32 in the semi-circular arc 322 area. The sealing ring 1 can then be completely wrapped around the column part 32. The positioning and assembly of the sealing ring 1 is convenient and facilitates the rapid assembly of the cover plate. Furthermore, the length and width dimensions of the column portion 32 satisfy 1 < (b + a) / a ≤ 10. This design prevents the column portion 32 from being too long. After the sealing ring 1 is opened through the circular through hole 13, the length of the sealing ring 1 that is opened is not too large. After the sealing ring 1 is fitted onto the column portion 32, it can quickly elastically recover and wrap around the column portion 32, which can prevent the sealing ring 1 from twisting or tilting. While facilitating the positioning and installation of the sealing ring 1, it can effectively ensure the sealing effect of the sealing ring 1, thereby preventing the cover plate from leaking air and ensuring the sealing performance of the cover plate.

[0056] like Figure 6 and Figure 10 As shown, in some embodiments, the cover plate further includes a riveting block 6. A supporting step is provided on the peripheral sidewall of the column portion 32. The column portion 32 is riveted to the riveting block 6, and the inner surface of the riveting block 6 abuts against the supporting step. When riveting the pole post 3, the riveting block 6 is easily deformed by the downward force of the riveting punch. The supporting step supports the riveting block 6, which can alleviate the sag in the middle area of ​​the riveting block 6, thereby improving the flatness of the riveting block 6. After the sealing ring 1 is installed, it is fitted onto the column portion 32 between the supporting step and the base plate 31.

[0057] like Figure 10 As shown, the side of the parallel part 11 facing the cover plate body 2 abuts against the cover plate body 2. The compression amount of the parallel part 11 at the mating point with the cover plate body 2 is f, where 10% ≤ f / d ≤ 50%, and the units of f and d are both mm. f / d is the compression ratio of the parallel part 11 between the base plate 31 and the cover plate body 2 after the sealing ring 1 is assembled, where 10% ≤ f / d ≤ 50%. This setting ensures that the parallel part 11 has a sufficient compression ratio, which can effectively guarantee the sealing performance between the base plate 31 and the cover plate body 2; at the same time, it can also prevent the compression ratio at the parallel part 11 from being too large and damaging the sealing ring 1, thus ensuring the sealing performance of the parallel part 11.

[0058] In some embodiments, such as Figure 9 and Figure 10As shown, the cover plate also includes a first insulating member 4, which is disposed on the outer surface of the cover plate body 2. The first insulating member 4 is provided with a clearance hole for the column part 32 to pass through. The clearance hole is located on the inner side of the circumferential outer edge of the mounting hole. One end of the vertical part 12 facing the first insulating member 4 abuts against the first insulating member 4. The compression amount of the vertical part 12 at the mating point with the first insulating member 4 is g, 0.2mm≤g≤0.5mm. This arrangement can ensure the sealing between the column part 32 and the first insulating member 4. When there is leaked electrolyte on the outer surface of the cover plate body 2, it can prevent the electrolyte from entering the column part 32 along the gap between the first insulating member 4 and the cover plate body 2, which is beneficial to improving the safety performance of the cover plate.

[0059] In some embodiments, the cover plate further includes a second insulating member 5. A riveting block 6 is disposed on the outer surface of the first insulating member 4, the second insulating member 5 is disposed on the inner surface of the cover plate body 2, the bottom plate 31 is disposed on the inner side of the inner surface of the second insulating member 5, and the column portion 32 passes through the second insulating member 5, the cover plate body 2, the first insulating member 4 and the riveting block 6 and is riveted to the riveting block 6.

[0060] The cover plate can be used for any battery cell with a narrow and long cover plate, such as blade cells and prismatic cells.

[0061] According to an embodiment of the present invention, another aspect provides a battery cell, including a housing and a cover plate of any of the above embodiments, wherein the housing has an opening and the cover plate is disposed on the opening.

[0062] In this battery cell structure, the sealing ring 1 has a circular hole 13 in the middle before installation. The circular hole does not need to be distinguished by direction. During installation, the sealing ring 1 can be opened from any direction to both sides and then fitted onto the column part 32 using the clamps. The two ends of the sealing ring 1 that are opened correspond to the semi-circular arc 322 area of ​​the column part 32. After the clamps are released, the two ends of the sealing ring 1 in the length direction are positioned and fitted onto the column part 32 in the semi-circular arc 322 area. The sealing ring 1 can then be completely fitted and wrapped around the column part 32. The positioning and assembly of the sealing ring 1 is convenient and facilitates the rapid assembly of the cover plate and the battery cell. Furthermore, the length and width dimensions of the column portion 32 satisfy 1 < (b + a) / a ≤ 10. This design prevents the column portion 32 from being too long. After the sealing ring 1 is opened through the circular through hole 13, the length of the sealing ring 1 that is opened is not too large. After the sealing ring 1 is fitted onto the column portion 32, it can quickly elastically recover and wrap around the column portion 32, which can prevent the sealing ring 1 from twisting or tilting. While facilitating the positioning and installation of the sealing ring 1, it can effectively ensure the sealing effect of the sealing ring 1, thereby preventing the cover plate from leaking air and ensuring the sealing performance of the cover plate and the battery cell.

[0063] In some optional embodiments, the battery cell includes a blade battery cell, which includes a housing with openings at both ends along its length. The cover plate includes a positive electrode cover plate and a negative electrode cover plate. A positive electrode post 3 is disposed on the positive electrode cover plate, and a negative electrode post 3 is disposed on the negative electrode cover plate. The positive electrode cover plate and the negative electrode cover plate are respectively disposed on the openings at both ends of the housing.

[0064] In other embodiments, the battery cell includes a prismatic battery cell, wherein the length of the cover body 2 of the prismatic battery cell is greater than its width.

[0065] According to an embodiment of the present invention, in another aspect, a battery pack is provided, comprising the battery cells of the above embodiments.

[0066] In this battery pack structure, the sealing ring 1 has a circular through hole 13 in the center before installation. The circular hole does not require directional differentiation, making the positioning and assembly of the sealing ring 1 convenient and facilitating rapid assembly of the cover and battery cells. Furthermore, the length and width dimensions of the cylindrical portion 32 satisfy 1 < (b+a) / a ≤ 10. This design prevents the cylindrical portion 32 from becoming excessively long. After the sealing ring 1 is opened through the circular through hole 13, the length of the opening is not excessive. Once the sealing ring 1 is fitted onto the cylindrical portion 32, it prevents twisting or skewing. This convenient positioning and installation of the sealing ring 1 effectively ensures its sealing effect, preventing air leakage from the cover and guaranteeing the sealing performance of the cover and battery cells, thus improving the overall performance of the battery pack.

[0067] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cover plate, characterized in that, include: The cover plate body is provided with mounting holes; The pole includes a base plate and a column portion disposed on the base plate. The long side of the column portion extends in the same direction as the long side of the cover plate, and the length of the column portion is greater than the width of the column portion. The cross-section of the column portion near the end of the base plate includes a rectangular smooth area in the middle and semi-circular arcs disposed at both ends of the smooth area in the middle. The diameter of the semi-circular arcs is equal to the width of the smooth area in the middle. The diameter of the semi-circular arcs is a, and the length of the smooth area in the middle along the long side of the cover plate is b. A sealing ring includes: a parallel portion and a vertical portion disposed on the parallel portion. The parallel portion and the vertical portion are provided with a through hole. Before the sealing ring is installed, the through hole is a circular hole, and the circumference of the circular hole is equal to the circumference of the cylindrical portion. The through hole is fitted onto the cylindrical portion, and the side of the parallel portion facing the base plate is attached to the base plate. The wall of the through hole is attached to the outer peripheral wall of the cylindrical portion. The radius of the through hole is r, r = (2b + πa) / 2π, 1 < (b + a) / a ≤ 10, and the units of a, b, and r are all mm. Along the radial direction of the sealing ring, the wall thickness of the vertical portion is c, where 0.5mm ≤ c ≤ 1mm; Along the thickness direction of the cover plate, the thickness of the parallel portion is d, 0.7mm≤d≤1.5mm.

2. The cover plate according to claim 1, characterized in that, 1 < (b + a) / a ≤ 3.

3. The cover plate according to claim 1 or 2, characterized in that, The radial width of the parallel section is e, where 1.5mm ≤ e ≤ 3mm.

4. The cover plate according to claim 1, characterized in that, The side of the parallel portion facing the cover plate body abuts against the cover plate body, and the compression amount of the parallel portion at the point where it mates with the cover plate body is f, where 10%≤f / d≤50%, and the units of f and d are both mm.

5. The cover plate according to claim 1 or 4, characterized in that, It also includes a first insulating member, which is disposed on the outer surface of the cover plate body. The first insulating member has a clearance hole for the column portion to pass through. The clearance hole is located inside the circumferential outer edge of the mounting hole. One end of the vertical portion facing the first insulating member abuts against the first insulating member. The compression amount of the vertical portion at the point of contact with the first insulating member is g, where 0.2mm≤g≤0.5mm.

6. A battery cell, characterized in that, It includes a housing and a cover plate according to any one of claims 1 to 5, wherein the housing has an opening and the cover plate is disposed on the opening.

7. A battery pack, characterized in that, Includes the battery cell described in claim 6.

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