Sealing ring, cover plate, battery cell and battery pack

Abstract

The invention relates to the technical field of batteries, and discloses a sealing ring, a cover plate, a battery cell and a battery pack. When the sealing ring is used, the sealing ring is arranged on a column body part of a pole column in a sleeving manner, before the sealing ring is mounted, a through hole in the middle of the sealing ring is a circular hole, the direction of the circular hole does not need to be distinguished, and the sealing ring is convenient to position and assemble. 1 < (b + a) / a < = 10, i.e., the length of the cylinder part is greater than the width of the cylinder part, and the length of the cylinder part is less than ten times of the width of the cylinder part. By means of the arrangement, the cylinder part can be prevented from being too long, after the sealing ring is opened through the circular through hole, the opened length of the sealing ring is not too large correspondingly, after the sealing ring is arranged on the cylinder part in a sleeving mode, elastic recovery can be rapidly generated, the cylinder part is wrapped with the sealing ring, the sealing ring can be effectively prevented from being twisted and inclined, and the service life of the sealing ring is prolonged. The sealing effect of the sealing ring can be effectively guaranteed under the condition that the sealing ring is convenient to position and install, so that air leakage of the cover plate can be prevented, and the sealing performance of the cover plate can be guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a sealing ring, a cover plate, a battery cell and a battery pack. Background Art

[0002] The cover plate adopting the pole riveting fixing method includes a rivet block, a first insulating member, a cover plate body, a second insulating member, a pole and a sealing ring. The cover plate body is provided with a mounting hole. The pole includes a base plate and a column portion. The column portion is riveted to the rivet block through the mounting hole and the rivet block; a through hole is provided in the middle of the sealing ring. The sealing ring includes a horizontal portion extending horizontally and a vertical portion extending vertically. The through hole is sleeved on the column portion. The side of the horizontal portion facing the base plate is in contact with the base plate to form a seal between the cover plate body and the base plate. The inner wall of the vertical portion is in contact with the column portion to form a seal between the cover plate body and the column portion.

[0003] Existing columns are generally cylindrical. For cells with narrow, long covers and high current requirements, increasing the current capacity of the cells by increasing the diameter of the cylindrical column is not feasible due to the narrow width of the cover body. Instead, the column must be enlarged along the length of the cover body, resulting in a narrow, long column. This non-circular cross-section of the column and the corresponding sealing ring also have a non-circular inner hole. This creates a directional seal during installation, making it difficult to position and assemble. Once the seal is attached to the column, it can easily become distorted, affecting its sealing performance and causing air leakage in the cover. 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 matched with the non-circular column portion is easily twisted and distorted 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, wherein the cover plate includes a cover plate body and a pole, the pole including a bottom plate and a column portion provided on the bottom plate, wherein 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; a cross section of the column portion near one end of the bottom plate includes a rectangular central smooth area and semicircular arcs provided at both ends of the central smooth area, wherein the diameter of the semicircular arc is equal to the width of the central smooth area, the diameter of the semicircular arc is a, and the length b of the central smooth area extending along the long side of the cover plate; the sealing ring includes:

[0006] A parallel portion and a vertical portion provided on the parallel portion, the parallel portion and the vertical portion are provided with a communicating through hole, the through hole is a circular hole, the circumference of the circular hole is equal to the circumference of the cylindrical portion; the through hole is suitable for being sleeved on the cylindrical portion, the side of the parallel portion facing the base plate is suitable for being attached to the base plate, and the hole wall of the through hole is suitable for being 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 effect: When the sealing ring of this structure is used, it is sleeved on the column part of the pole. Before the sealing ring is installed, the through hole in the middle is a circular hole. The circular hole does not need to distinguish the direction. When installing, the sealing ring can be stretched out from any direction to both sides by using a clamp and then sleeved on the column part. The stretched ends of the sealing ring correspond to the semi-circular area of ​​the column part. After the clamp is loosened, the two ends of the sealing ring in the length direction are positioned and sleeved on the column part at the semi-circular area. The sealing ring can be sleeved on the column part as a whole, and the positioning and assembly of the sealing ring are convenient. The circumference of the through hole of the sealing ring is equal to the circumference of the outer peripheral wall of the column part. The circumference of the outer peripheral wall of the column part is 2b+πa, and the circumference of the through hole is 2πr, then r=(2b+πa) / 2π; b+a is the total length of the column part, a is the width of the column part, 1<(b+a) / a≤10, that is, the length of the column part is greater than its width, and the length of the column part is less than ten times the width of the column part. If the length-to-width ratio of the column is too large, the column will be long, and the sealing ring will need to be stretched out longer toward both ends. Once the sealing ring is placed on the column, it will easily twist and distort, causing the parallel portion to not fit properly with the base plate, or the vertical portion to not fully fit properly with the sidewalls of the column. 1<(b+a) / a≤10. This configuration prevents the column from being too long. After the sealing ring is stretched out from the circular through hole, the stretched length of the sealing ring is not excessive. After the sealing ring is placed on the column, it can quickly elastically recover and wrap around the column, effectively preventing the sealing ring from twisting and distorting. While facilitating the positioning and installation of the sealing ring, it can effectively ensure the sealing effect of the sealing ring, thereby preventing air leakage from the cover plate and ensuring the sealing performance of the cover plate.

[0008] In an optional embodiment, 1<(b+a) / a≤3.

[0009] Beneficial Effects: This arrangement further optimizes the length-to-width ratio of the column, further reducing the length of the expanded sealing ring. The sealing ring can be placed on the column after being slightly expanded, preventing the sealing ring from twisting or skewing. This improves the fit between the parallel portion and the base plate, as well as the fit between the vertical portion and the column. While facilitating the positioning and installation of the sealing ring, it further ensures the sealing effect of the sealing ring and further improves the sealing performance of the cover. Furthermore, 1 < (b + a) / a ≤ 3 prevents the length of the column from being too long and affecting its strength, ensuring the upper limit of the length-to-width ratio of the column, thereby ensuring the strength of the column and the pole.

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

[0011] Beneficial effects: 0.5mm≤c≤1mm, which can ensure the minimum value of the vertical wall thickness, facilitate vulcanization molding of the column part, and ensure the consistency of the wall thickness of the vertical parts of the sealing ring at various locations around the circumference, so as to ensure that the vertical parts at various locations around the circumference are effectively fitted on the column part, and can ensure the sealing effect of the vertical parts, thereby ensuring the sealing effect of the cover plate; at the same time, it can avoid the wall thickness of the vertical part being too thick and occupying too much space, thereby avoiding the increase in cost.

[0012] In an optional embodiment, the thickness of the parallel portion is d, 0.7 mm ≤ d ≤ 1.5 mm.

[0013] Beneficial effect: 0.7mm≤d≤1.5mm, which can not only ensure the safe distance between the cover body and the base plate, but also ensure the compression amount of the parallel part, thereby ensuring the insulation protection and sealing effect of the parallel part on the base plate and the cover body; at the same time, it can avoid the thickness of the parallel part being too thick and occupying too much space, thereby avoiding the increase in cost.

[0014] In an optional embodiment, the radial width of the parallel portion is e, 1.5 mm ≤ e ≤ 3 mm.

[0015] In a second aspect, the present invention further provides a cover plate, comprising:

[0016] The cover body is provided with a mounting hole;

[0017] A pole, comprising a base plate and a column portion provided on the base plate, wherein 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; a cross section of the column portion near one end of the base plate comprises a rectangular central smooth region and semicircular arcs provided at both ends of the central smooth region, wherein the diameter of the semicircular arc is equal to the width of the central smooth region, the diameter of the semicircular arc is a, and the length of the central smooth region extending along the long side of the cover plate is b;

[0018] In any of the aforementioned sealing rings, the through hole is sleeved on the column, the parallel portion is affixed to the base plate, and the hole wall of the through hole is affixed to the outer peripheral wall of the column; the radius of the through hole is r, where r = (2b + πa) / 2π, and 1 < (b + a) / a ≤ 10. The cover plate includes the sealing ring and has the same technical effects as the sealing ring, and will not be further described here.

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

[0020] Beneficial effect: This arrangement can ensure that the parallel portion has a sufficient compression rate, which can effectively ensure the sealing between the bottom plate and the cover plate body; at the same time, it can also prevent the compression rate at the parallel portion from being too large and damaging the sealing ring, which can ensure the sealing of the parallel portion.

[0021] In an optional embodiment, a first insulating member is further included, which is arranged on the outer surface of the cover body. The first insulating member is provided with an avoidance hole for the column portion to pass through, and the avoidance hole is located on the inner side of 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, and the compression amount of the vertical portion at the cooperation with the first insulating member is g, 0.2mm≤g≤0.5mm.

[0022] Beneficial effect: Such a setting can ensure the sealing between the column part and the first insulating part. When there is leakage of electrolyte on the outer surface of the cover body, it can prevent the electrolyte from entering the column part along the gap between the first insulating part and the cover body, which is beneficial to improving the safety performance of the cover.

[0023] In a third aspect, the present invention further 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 over the opening. The battery cell includes a sealing ring, which has the same technical effects as the sealing ring and is not further described here.

[0024] In a fourth aspect, the present invention further provides a battery pack comprising the above-mentioned battery cell. The battery pack includes a sealing ring, which has the same technical effect as the sealing ring and is not further described here. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a schematic diagram of the three-dimensional structure 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 is shown;

[0028] Figure 3 for Figure 1 A schematic diagram of the three-dimensional structure 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 shown;

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

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

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

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

[0034] Figure 9 for Figure 8 AA sectional view;

[0035] Figure 10 for Figure 9 A partial enlarged schematic diagram;

[0036] Figure 11 for Figure 1 Exploded view of the cover shown.

[0037] Description of reference numerals:

[0038] 1. Sealing ring; 11. Parallel portion; 12. Vertical portion; 13. Through hole; 2. Cover plate body; 3. Pole; 31. Bottom plate; 32. Column portion; 321. Middle smooth area; 322. Semicircular arc; 4. First insulating member; 5. Second insulating member; 6. Riveted block. DETAILED DESCRIPTION

[0039] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0040] The column portion in the related art is generally cylindrical. For cells with narrow and long covers and high current requirements, the current capacity of the cell cannot be increased by increasing the diameter of the cylindrical column portion due to the narrow width of the cover body. The column portion can only be increased in the length direction of the cover body, thus forming a narrow and long column portion. This column portion has a non-circular cross section, and the inner hole of the sealing ring that matches it is also non-circular. In this case, the installation of the sealing ring is directional. The inner hole of the sealing ring has a long side and a wide side. During installation, the long side and wide side of the inner hole need to correspond to the long side and wide side of the column portion respectively. When installing the sealing ring, the sealing ring is opened and placed on the column portion by clamping claws. The sealing ring is difficult to position during installation and is difficult to assemble. After the clamping claws are released, the sealing ring is easily misplaced or twisted, and the sealing ring cannot fit well on the pole base plate and / or the column portion, which affects the sealing performance of the sealing ring and causes air leakage in the cover.

[0041] The following combination Figures 1 to 11 , describing embodiments of the present invention.

[0042] According to an embodiment of the present invention, on the one hand, a sealing ring 1 is provided, which is suitable for use in a cover plate, wherein the cover plate includes a cover plate body 2 and a pole 3, wherein the pole 3 includes a base plate 31 and a column portion 32 provided on the base plate 31, wherein 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 one end of the base plate 31 includes a rectangular middle smooth area 321 and semicircular arcs 322 provided at both ends of the middle smooth area 321, wherein the diameter of the semicircular arc 322 is equal to the width of the middle smooth area 321, the diameter of the semicircular arc 322 is a, and the length of the middle smooth area 321 extending along the long side of the cover plate is b.

[0043] The sealing ring 1 includes a parallel portion 11 and a vertical portion 12 provided on the parallel portion 11. A communicating through hole 13 is provided on the parallel portion 11 and the vertical portion 12. The through hole 13 is a circular hole, and the circumference of the circular hole is equal to the circumference of the cylindrical portion 32. The through hole 13 is suitable for being sleeved on the cylindrical portion 32. The side of the parallel portion 11 facing the bottom plate 31 is suitable for being attached to the bottom plate 31, and the hole wall of the through hole 13 is suitable for being attached to the outer peripheral wall of the cylindrical portion 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 the sealing ring 1 of this structure is used, it is sleeved on the column part 32 of the pole 3. Before the sealing ring 1 is installed, the through hole 13 in the middle is a circular hole, and the circular hole does not need to distinguish the direction. During installation, the sealing ring 1 can be stretched out from any direction toward both sides using a clamping jaw and then sleeved on the column part 32. The stretched ends of the sealing ring 1 correspond to the semicircular arc 322 area of ​​the column part 32. After the clamping jaw is loosened, the two ends of the sealing ring 1 in the length direction are positioned and sleeved on the column part 32 in the semicircular arc 322 area. The sealing ring 1 can be sleeved and wrapped around the column part 32 as a whole, and the positioning and assembly of the sealing ring 1 are convenient. The circumference of the through hole 13 of the sealing ring 1 is equal to the circumference of the outer wall of the column portion 32. The circumference of the outer wall of the column portion 32 is 2b+πa, and the circumference of the through hole 13 is 2πr, so r=(2b+πa) / 2π; b+a is the total length of the column portion 32, and a is the width of the column portion 32. 1<(b+a) / a≤10, that is, the length of the column portion 32 is greater than its width, and the length of the column portion 32 is less than ten times the width of the column portion 32. If the aspect ratio of the column portion 32 is too large, the length of the column portion 32 is too long, and the sealing ring 1 needs to be stretched longer towards both ends. After the sealing ring 1 is placed on the column portion 32, it is easy to twist and distort, resulting in the parallel portion 11 not being able to fit with the bottom plate 31, or the vertical portion 12 not being able to fully fit with the side wall of the column portion 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 stretched out from the circular through hole 13, the corresponding stretched length of the sealing ring 1 is not too large. After the sealing ring 1 is sleeved on the column part 32, it can quickly recover elastically and wrap around the column part 32, which can effectively prevent the sealing ring 1 from twisting and skewing. While facilitating the positioning and installation of the sealing ring 1, the sealing effect of the sealing ring 1 can be effectively guaranteed, thereby preventing the cover from leaking and ensuring the sealing of the cover.

[0045] In some optional embodiments, 1<(b+a) / a≤3. This setting can further optimize the aspect ratio of the column portion 32 and further reduce the length of the sealing ring 1 when stretched. The sealing ring 1 can be placed on the column portion 32 after being slightly stretched, which can prevent the sealing ring 1 from twisting and skewing, and is conducive to improving the fit between the parallel portion 11 and the bottom plate 31, and the fit between the vertical portion 12 and the column portion 32. While facilitating the positioning and installation of the sealing ring 1, the sealing effect of the sealing ring 1 can be further guaranteed, and the sealing performance of the cover plate can be further improved. At the same time, 1<(b+a) / a≤3 can prevent the length of 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] Pole posts 3 with different values ​​of a, b, and (b+a) / a were designed, as well as sealing rings 1 corresponding to the circumferences of the column portions 32 of the different pole posts 3. Before installation, the through hole 13 of the sealing ring 1 was a circular hole. The sealing ring 1 was sleeved and assembled on the pole post 3, and the fit between the sealing ring 1 and the pole post 3 was observed. The test results are shown in Table 1.

[0047] Table 1

[0048]

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

[0050] like Figure 3As shown, in some embodiments, along the radial direction of the sealing ring 1, the wall thickness of the vertical portion 12 is c, 0.5mm≤c≤1mm. This setting can ensure the minimum wall thickness of the vertical portion 12. After the cover is assembled, the vertical portion 12 is blocked between the hole wall of the mounting hole of the cover body 2 and the column portion 32, c≥0.5mm. This can prevent the wall thickness of the vertical portion 12 from being too small to affect its insulation protection effect, and can prevent the vertical portion 12 from being punctured under the action of a strong electric field, thereby ensuring the insulation protection and sealing effect between the hole wall of the mounting hole of the cover body 2 and the column portion 32. In addition, if the wall thickness of the vertical portion 12 of the sealing ring 1 is too small, it is difficult to ensure the consistency of the wall thickness of the sealing ring 1 at all locations along the circumference during molding, which can easily lead to inconsistent wall thickness along the circumference of the sealing ring 1. That is, the wall thickness of the vertical portion 12 at some locations along the circumference of the sealing ring 1 is thin, while the wall thickness of the vertical portion 12 at other locations along the circumference of the sealing ring 1 is thick. This makes it difficult to ensure that the vertical portion 12 at all locations along the circumference of the sealing ring 1 is effectively attached to the column portion 32, which will affect the sealing performance of the cover plate. c ≥ 0.5mm, which can ensure the minimum value of the vertical wall thickness, facilitate vulcanization molding of the column portion 32, and ensure the consistency of the wall thickness of the vertical portion 12 at all locations along the circumference of the sealing ring 1, thereby ensuring that the vertical portion 12 at all locations along the circumference is effectively attached to the column portion 32, ensuring the sealing effect of the vertical portion 12, and thus ensuring the sealing effect of the cover plate; at the same time, it can avoid the vertical portion 12 being too thick and occupying too much space, thereby avoiding increasing costs.

[0051] After the sealing ring 1, the cover body 2 and the pole 3 are assembled into the cover, the bottom plate 31 is located on the inner side of the inner surface of the cover body 2. A second insulating member 5 is also provided between the cover body 2 and the bottom plate 31. The second insulating member 5 plays an insulating and protective role between the bottom plate 31 and the cover body 2. In order to prevent the second insulating member 5 between the bottom plate 31 and the cover body 2 from being broken through, the distance between the facing sides of the cover body 2 and the bottom plate 31 needs to be greater than or equal to 0.5mm. The two sides of the parallel portion 11 respectively abut the inner wall surface of the cover body 2 and the outer wall surface of the bottom plate 31. Therefore, the thickness of the parallel portion 11 needs to be greater than or equal to 0.5mm. Greater than 0.5mm, the parallel portion 11 will produce a certain degree of compression in its thickness direction after installation. 0.5mm plus the compression of the parallel portion 11, the thickness of the parallel portion 11 before compression is d, 0.7mm≤d≤1.5mm, which can ensure a safe distance between the cover body 2 and the bottom plate 31, while also ensuring the compression of the parallel portion 11, thereby ensuring the insulation protection and sealing effect of the parallel portion 11 on the bottom plate 31 and the cover body 2; at the same time, it can avoid the thickness of the parallel portion 11 being too thick and occupying too much space, thereby avoiding an 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, and the wall thickness of the vertical portion 12 is c ≥ 0.5 mm. 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 outside the circumferential side wall of the vertical portion 12, so that the two sides of the step respectively abut against the cover body 2 and the bottom plate 31, thereby providing insulation and sealing between the bottom plate 31 and the cover body 2. The parallel portion 11 needs to form a step on the circumferential outer side 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. Taking into account the assembly tolerance and compression margin, in some embodiments, the radial width e of the parallel portion 11 satisfies 1.5 mm ≤ e ≤ 3 mm. This configuration can ensure the insulation and sealing performance between the cover body 2 and the bottom plate 31; at the same time, it can avoid design redundancy caused by an excessively large e, and prevent the parallel portion 11 from occupying too much space and increasing costs.

[0053] According to an embodiment of the present invention, on the other hand, a cover plate is provided, including a cover plate body 2 , a pole 3 and a sealing ring 1 .

[0054] In which, a mounting hole is provided on the cover body 2; the pole 3 includes a base plate 31 and a column portion 32 provided 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 one end of the base plate 31 includes a rectangular central smooth area 321 and semicircular arcs 322 provided at both ends of the central smooth area 321, the diameter of the semicircular arc 322 is equal to the width of the central smooth area 321, the diameter of the semicircular arc 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 portion 32, the parallel portion 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 portion 32; the radius of the through hole 13 is r, r=(2b+πa) / 2π, 1<(b+a) / a≤10.

[0055] The cover plate of this structure has a sealing ring 1 on which the through hole 13 in the middle is a circular hole before installation. The circular hole does not need to distinguish the direction. During installation, the sealing ring 1 can be stretched out from any direction toward both sides using a clamping jaw and then sleeved on the column portion 32. The stretched ends of the sealing ring 1 correspond to the semicircular arc 322 area of ​​the column portion 32. After the clamping jaw is released, the two ends of the sealing ring 1 in the length direction are positioned and sleeved on the column portion 32 in the semicircular arc 322 area. The sealing ring 1 can be completely sleeved and wrapped on the column portion 32. The positioning and assembly of the sealing ring 1 are convenient, which is conducive to the rapid assembly of the cover plate. In addition, the length and width dimensions of the column portion 32 satisfy 1<(b+a) / a≤10. This arrangement can prevent the length of the column portion 32 from being too long. After the sealing ring 1 is stretched out from the circular through hole 13, the corresponding stretched length of the sealing ring 1 is not too large. After the sealing ring 1 is sleeved on the column portion 32, it can quickly recover elastically and wrap around the column portion 32, which can prevent the sealing ring 1 from twisting and skewing. While facilitating the positioning and installation of the sealing ring 1, the sealing effect of the sealing ring 1 can be effectively guaranteed, thereby preventing the cover from leaking and ensuring the sealing of the cover.

[0056] like Figure 6 and Figure 10 As shown, in some embodiments, the cover plate further includes a rivet block 6. A support step is provided on the peripheral sidewall of the column portion 32. The column portion 32 is riveted to the rivet block 6, and the inner surface of the rivet block 6 abuts the support step. When riveting the terminal 3, the rivet block 6 is easily deformed by the downward force of the riveting punch. The support step supports the rivet block 6, which can alleviate the degree of collapse in the central area of ​​the rivet block 6, thereby improving the flatness of the rivet block 6. After installation, the sealing ring 1 is mounted on the column portion 32 between the support step and the base plate 31.

[0057] like Figure 10 As shown, the side of the parallel portion 11 facing the cover body 2 abuts against the cover body 2. The compression of the parallel portion 11 at the point of engagement with the cover body 2 is f, with 10% ≤ f / d ≤ 50%, where both f and d are expressed in mm. f / d represents the compression ratio of the parallel portion 11 between the base plate 31 and the cover body 2 after the sealing ring 1 is assembled, with 10% ≤ f / d ≤ 50%. This arrangement ensures sufficient compression of the parallel portion 11, effectively ensuring a seal between the base plate 31 and the cover body 2. It also prevents excessive compression of the parallel portion 11 from damaging the sealing ring 1, ensuring a secure seal.

[0058] In some embodiments, as Figure 9 and Figure 10As shown, the cover plate also includes a first insulating member 4, which is arranged on the outer surface of the cover plate body 2. The first insulating member 4 is provided with an avoidance hole for the column portion 32 to pass through, and the avoidance hole is located on the inner side of the circumferential outer edge of the mounting hole. One end of the vertical portion 12 facing the first insulating member 4 abuts against the first insulating member 4, and the compression amount of the vertical portion 12 at the cooperation with the first insulating member 4 is g, 0.2mm≤g≤0.5mm. This arrangement can ensure the sealing between the column portion 32 and the first insulating member 4. When there is leakage of electrolyte on the outer surface of the cover plate body 2, the electrolyte can be prevented from entering the column portion 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 further includes a second insulating member 5. A rivet block 6 is provided on the outer surface of the first insulating member 4, the second insulating member 5 is provided on the inner surface of the cover body 2, the bottom plate 31 is provided inside the inner surface of the second insulating member 5, and the column portion 32 passes through the second insulating member 5, the cover body 2, the first insulating member 4, and the rivet block 6 and is riveted to the rivet block 6.

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

[0061] According to an embodiment of the present invention, on the other hand, a battery cell is provided, comprising a shell and a cover according to any one of the above embodiments, wherein the shell is provided with an opening, and the cover is provided on the opening.

[0062] For the battery cell of this structure, before installation, the through hole 13 in the middle of the sealing ring 1 is a circular hole, and the circular hole does not need to be distinguished in direction. During installation, the sealing ring 1 can be stretched out from any direction toward both sides using a clamping jaw and then sleeved on the column part 32. The stretched ends of the sealing ring 1 correspond to the semicircular arc 322 area of ​​the column part 32. After the clamping jaw is released, the two ends of the sealing ring 1 in the length direction are positioned and sleeved on the column part 32 in the semicircular arc 322 area. The sealing ring 1 can be sleeved and wrapped around the column part 32 as a whole. The positioning and assembly of the sealing ring 1 are convenient, which is conducive to the rapid assembly of the cover plate and the battery cell. In addition, the length and width dimensions of the column portion 32 satisfy 1<(b+a) / a≤10. This arrangement can prevent the length of the column portion 32 from being too long. After the sealing ring 1 is stretched out from the circular through hole 13, the corresponding stretched length of the sealing ring 1 is not too large. After the sealing ring 1 is sleeved on the column portion 32, it can quickly recover elastically and wrap around the column portion 32, which can prevent the sealing ring 1 from twisting and skewing. While facilitating the positioning and installation of the sealing ring 1, the sealing effect of the sealing ring 1 can be effectively guaranteed, thereby preventing the cover from leaking and ensuring the sealing of the cover and the battery cell.

[0063] In some optional embodiments, the battery cell includes a blade battery cell, the blade battery cell includes a shell, and the two ends of the shell are open in the length direction. The cover plate includes a positive cover plate and a negative cover plate, a positive electrode column 3 is provided on the positive cover plate, and a negative electrode column 3 is provided on the negative cover plate. The positive cover plate and the negative cover plate are respectively provided on the openings at both ends of the shell.

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

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

[0066] In a battery pack with this structure, before installation, the through hole 13 in the middle of the sealing ring 1 is a circular hole. The circular hole does not need to be oriented, making the positioning and assembly of the sealing ring 1 easy, and facilitating the rapid assembly of the cover and battery cells. Furthermore, the length and width of the column portion 32 satisfy 1<(b+a) / a≤10. This arrangement prevents the length of the column portion 32 from being too long. After the sealing ring 1 is stretched out from the circular through hole 13, the stretched length of the sealing ring 1 is also not excessive. After the sealing ring 1 is sleeved onto the column portion 32, it prevents the sealing ring 1 from twisting or skewing. While facilitating the positioning and installation of the sealing ring 1, it effectively ensures the sealing effect of the sealing ring 1, thereby preventing air leakage from the cover and ensuring the sealing between the cover and battery cells, thereby improving the overall performance of the battery pack.

[0067] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A sealing ring, characterized in that: Suitable for use in a cover plate, the cover plate includes a cover plate body and a pole, the pole includes a bottom plate and a column portion provided on the bottom 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 bottom plate includes a rectangular middle smooth area and semicircular arcs provided at both ends of the middle smooth area, the diameter of the semicircular arc is equal to the width of the middle smooth area, the diameter of the semicircular arc is a, and the length of the middle smooth area extending along the long side of the cover plate is b; the sealing ring includes: A parallel portion and a vertical portion provided on the parallel portion, the parallel portion and the vertical portion are provided with a communicating through hole, the through hole is a circular hole, the circumference of the circular hole is equal to the circumference of the cylindrical portion; the through hole is suitable for being sleeved on the cylindrical portion, the side of the parallel portion facing the base plate is suitable for being attached to the base plate, and the hole wall of the through hole is suitable for being 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.

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

3. The sealing ring according to claim 1 or 2, characterized in that: Along the radial direction of the sealing ring, the wall thickness of the vertical portion is c, 0.5mm≤c≤1mm.

4. The sealing ring according to claim 1 or 2, characterized in that: Along the thickness direction of the cover plate, the thickness of the parallel portion is d, 0.7 mm ≤ d ≤ 1.5 mm.

5. The sealing ring according to claim 1 or 2, characterized in that: The radial width of the parallel portion is e, 1.5 mm ≤ e ≤ 3 mm.

6. A cover plate, characterized in that: include: The cover body is provided with a mounting hole; A pole, comprising a base plate and a column portion provided on the base plate, wherein 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; a cross section of the column portion near one end of the base plate comprises a rectangular central smooth region and semicircular arcs provided at both ends of the central smooth region, wherein the diameter of the semicircular arc is equal to the width of the central smooth region, the diameter of the semicircular arc is a, and the length of the central smooth region extending along the long side of the cover plate is b; The sealing ring according to any one of claims 1 to 5, wherein the through hole is sleeved on the column portion, the parallel portion is affixed to the bottom plate, and the hole wall of the through hole is affixed to the outer peripheral wall of the column portion; the radius of the through hole is r, r = (2b + πa) / 2π, 1 < (b + a) / a ≤ 10.

7. The cover plate according to claim 6, characterized in that: The parallel portion faces the cover body on one side thereof and abuts against the cover body. The compression amount of the parallel portion at the joint with the cover body is f, 10%≤f / d≤50%, and the units of f and d are both mm.

8. The cover plate according to claim 6 or 7, characterized in that: It also includes a first insulating part, which is arranged on the outer surface of the cover body. The first insulating part is provided with an avoidance hole for the column part to pass through, and the avoidance hole is located on the inner side of the circumferential outer edge of the mounting hole. One end of the vertical part facing the first insulating part abuts on the first insulating part, and the compression amount of the vertical part at the cooperation with the first insulating part is g, 0.2mm≤g≤0.5mm.

9. A battery cell, characterized in that: The invention comprises a shell and the cover plate according to any one of claims 6 to 8, wherein the shell is provided with an opening, and the cover plate is provided on the opening.

10. A battery pack, characterized in that: Including the battery cell according to claim 9.

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