Battery cell cover plate assembly, battery cell, and battery pack

Abstract

The application relates to the technical field of batteries and discloses a battery cell cover plate assembly, a battery cell and a battery pack, wherein the battery cell cover plate assembly mainly comprises a cover plate, a pole and a sealing ring; the cover plate is provided with a first mounting hole penetrating through; the pole comprises a base and a pole body connected along a Z direction, the pole body is arranged in the first mounting hole and extends out of the upper surface of the cover plate, the outer peripheral wall of one end of the pole body extending out of the first mounting hole is provided with a protrusion, and the protrusion extends along the circumference of the pole body; the sealing ring is sleeved outside the pole body and clamped between the cover plate and the base; and the sealing ring is also located between the protrusion and the base. The battery cell cover plate assembly of the application is provided with the protrusion on the pole body, the sealing ring is located between the protrusion and the base, the protrusion is used for protecting the sealing ring when the cover plate is assembled, the risk that the sealing ring is pressed over by the cover plate is reduced, the sealing effect is improved, and the reliability and safety of the battery cell are ensured.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to cell cover assemblies, cells, and battery packs. Background Technology

[0002] New energy batteries, with their high energy density, high operating voltage, excellent charge retention capability and long cycle life, have been widely used in many important fields such as transportation power supply, power storage equipment, energy storage system and aerospace and military industries.

[0003] As the smallest unit in a battery pack, a battery cell typically comprises components such as electrolyte, electrode assembly, bare cell insulating sheet, cover plate assembly, and housing. The housing and cover plate assembly are fixedly connected by welding, forming a sealed space to accommodate the electrode assembly. The cover plate assembly generally integrates functional areas such as terminals, electrolyte injection holes, and explosion-proof valves, and is sealed to the housing by welding along its perimeter.

[0004] As the energy density requirements of battery packs continue to increase, current cell designs are showing a trend of gradually reducing thickness and correspondingly shrinking cover width. At the same time, to enhance current carrying capacity, the diameter of the terminal post is constantly increasing, leading to a significant reduction in the installation gap between the cover and the sealing ring. During the pressing process, issues such as positioning accuracy can easily cause the sealing ring to collapse on one side or fold over, resulting in airtightness failure and leakage of the cover, severely impacting the reliability and lifespan of the battery cell. Summary of the Invention

[0005] This invention provides a cell cover assembly, a cell, and a battery pack to solve the problem that when the diameter of the cell's terminal rod increases, the installation gap between the cover and the sealing ring becomes too small, which easily causes the sealing ring to be crushed or folded during cover pressing, thus affecting the sealing effect of the cover.

[0006] In a first aspect, the present invention provides a battery cell cover assembly, comprising: The cover plate has a first mounting hole that extends along the Z direction; The pole includes a base and a pole body connected along the Z direction. The pole body passes through the first mounting hole and extends out of the upper surface of the cover plate. The outer peripheral wall of the end of the pole body that extends out of the first mounting hole is provided with a protrusion. The protrusion extends circumferentially along the pole body in the XY plane. A sealing ring is fitted onto the outer side of the pole body in the XY plane and sandwiched between the cover plate and the base; along the Z direction, the sealing ring is also located between the protrusion and the base.

[0007] Beneficial effects: The battery cell cover assembly of the present invention has a protrusion on the outer peripheral wall of the end of the electrode body that extends out of the first mounting hole, and a sealing ring is placed between the protrusion and the base. When the cover is assembled, the protrusion can effectively protect the top of the sealing ring, significantly reducing the risk of crushing or folding the top of the sealing ring when the cover is pressed down, thereby improving the sealing effect and also helping to improve the reliability and service life of the battery cell.

[0008] In one alternative implementation, the length of the protrusion along the X and / or Y directions is L1, satisfying 0.03 mm ≤ L1 ≤ 0.05 mm; And / or, along the Z direction, the height of the protrusion is H1, satisfying 0.5 mm ≤ H1 ≤ 2 mm.

[0009] Beneficial effects: By controlling the length L1 and / or height H1 of the protrusion within a suitable range, the protrusion ensures sufficient structural strength and effective protective area. If L1 is too small, the protective area of ​​the protrusion on the sealing ring is too small, and the risk of the sealing ring crushing or folding remains high. If L1 is too large, it is inconvenient to assemble the sealing ring, affecting assembly efficiency, and the protrusion occupies too much space. If H1 is too small, the structural strength of the protrusion is weak, and the protrusion is prone to deformation or even breakage during assembly, resulting in poor reliability. If H1 is too large, it is inconvenient to assemble the sealing ring, affecting assembly efficiency, and the protrusion occupies too much space.

[0010] In one optional embodiment, the pole body includes a first pole and a second pole, one end of the second pole is connected to the first pole, and the other end is connected to the base. The projection of the first pole along the XY plane falls into the projection of the second pole along the XY plane, so that a first step is formed between the first pole and the second pole. The protrusion is provided on the outer peripheral wall of the second pole and is connected to the first step through a first chamfer. Along the X and / or Y directions, the length of the first chamfer is L8, satisfying 0.2 mm ≤ L8 ≤ 0.3 mm; And / or, along the Z direction, the length of the first chamfer is L9, satisfying 0.2 mm ≤ L9 ≤ 0.3 mm.

[0011] Beneficial effects: The first column is used to rivet the rivet to fix the cover plate to the pole. The second column is used to install the sealing ring. A first chamfer is set at the protrusion and the first step to form a transition surface so that the sealing ring can be fitted into the second column in the Z direction. This makes it easier to assemble the sealing ring and also prevents the sealing ring from being scratched by the protrusion.

[0012] In one optional embodiment, the sealing ring includes a first sealing part and a second sealing part connected along the Z direction. The first sealing part is sandwiched between the cover plate and the base. The second sealing part passes through the first mounting hole and is sleeved on the outer side of the second column in the XY plane. The inner circumferential side of the first sealing part away from the second sealing part has a second chamfer. Along the X and / or Y directions, the length of the second chamfer is L10, satisfying 0.2 mm ≤ L10 ≤ 0.3 mm, L10 ≥ L8; And / or, along the Z direction, the length of the second chamfer is L11, satisfying 0.2 mm ≤ L11 ≤ 0.3 mm, L11 ≥ L9.

[0013] Beneficial effects: The first sealing part is used to seal the cover plate and the pole post, and the second sealing part is used to insulate the cover plate and the pole post. A second chamfer, not smaller than the first chamfer, is formed on the inner circumference of the first sealing part to create a guiding slope, allowing the sealing ring to be more smoothly fitted into the second pole post.

[0014] In one alternative embodiment, along the Z direction, the second sealing portion extends out of the first mounting hole, and the length of the second sealing portion extending beyond the first mounting hole is L2, satisfying 0.6 mm ≤ L2 ≤ 0.8 mm.

[0015] Beneficial effect: By controlling L2 within a suitable range, the risk of the second sealing part being crushed or folded by the cover plate can be further reduced.

[0016] In one optional embodiment, the second sealing part has an installation gap between its outer peripheral wall in the XY plane and the wall of the first mounting hole, and the length of the installation gap is L3 along the X direction and / or Y direction, satisfying 0.25 mm ≤ L3 ≤ 0.6 mm.

[0017] Beneficial effects: By controlling the length of the installation gap between the outer peripheral wall of the second sealing part and the wall of the first mounting hole within a suitable range, sufficient installation space can be left when assembling the cover plate, reducing the risk of the cover plate contacting the second sealing part, thereby further reducing the risk of the second sealing part being crushed or folded by the cover plate.

[0018] In one optional embodiment, the cross-sectional area of ​​the first sealing part in the XY plane is greater than that of the second sealing part in the XY plane, so that a second step is formed at the connection between the first sealing part and the second sealing part, and the second step is provided with a compression area formed after being pressed against the lower surface of the cover plate. Along the X and / or Y directions, the width of the compression region is L4, satisfying L4≥1 mm.

[0019] Beneficial effects: By controlling the lower limit of the width L4 of the compression zone, it is ensured that the first sealing part can obtain sufficient compression, avoiding the risk of seal failure and air leakage due to insufficient compression.

[0020] In one optional embodiment, it further includes a lower insulating member disposed on the lower surface of the cover plate along the Z direction, the lower insulating member having a second mounting hole corresponding to the first mounting hole, the second column passing through the second mounting hole, and the first sealing part being located between the second column and the lower insulating member; The first sealing part has an assembly gap between its outer peripheral wall in the XY plane and the wall of the second mounting hole. The width of the assembly gap is L5 along the X and / or Y directions, which satisfies 0.2 mm ≤ L5 ≤ 0.5 mm.

[0021] Beneficial effects: By reserving an appropriate width of assembly gap between the first sealing part and the lower insulating part, space is provided to accommodate the expansion of the sealing ring after being compressed, avoiding excessive compression of the lower insulating part due to the expansion of the sealing ring, and preventing the lower insulating part from expanding.

[0022] Secondly, the present invention also provides a battery cell, comprising: The housing has an opening at at least one end; The pole assembly is located within the housing; The aforementioned cell cover assembly has the cover plate placed over the opening and connected to the housing.

[0023] Beneficial effects: The battery cell of the present invention has a protrusion on the outer peripheral wall of the end of the electrode body that extends out of the first mounting hole, and a sealing ring is placed between the protrusion and the base. When the cover plate is assembled, the protrusion can effectively protect the top of the sealing ring, significantly reducing the risk of crushing or folding the top of the sealing ring when the cover plate is pressed down, thereby improving the sealing effect and also helping to improve the reliability and service life of the battery cell.

[0024] Thirdly, the present invention also provides a battery pack comprising: at least one of the above-described battery cells.

[0025] Beneficial effects: Since the battery pack includes battery cells, it has the same effects as the battery cells, which will not be repeated here. Attached Figure Description

[0026] 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.

[0027] Figure 1 This is a schematic diagram of the structure of a battery cell cover assembly according to an embodiment of the present invention; Figure 2 for Figure 1 Top view; Figure 3 for Figure 2 Sectional view at point AA; Figure 4 This is a schematic diagram of the electrode post structure of a battery cell cover assembly according to an embodiment of the present invention; Figure 5 for Figure 4 Top view; Figure 6 for Figure 5 Sectional view at BB; Figure 7 for Figure 6 Enlarged view of section C in the image; Figure 8 This is a schematic diagram of the sealing ring structure of a battery cell cover assembly according to an embodiment of the present invention; Figure 9 for Figure 8 Top view; Figure 10 for Figure 9 Sectional view at DD; Figure 11 A schematic diagram of the sealing ring and electrode post of a battery cell cover assembly according to an embodiment of the invention; Figure 12 for Figure 11 Top view; Figure 13 for Figure 12 Sectional view at EE.

[0028] Explanation of reference numerals in the attached figures: 1. Cover plate; 101. First mounting hole; 2. Pole post; 201. Base; 202. Pole post body; 2021. First column; 2022. Second column; 2023. First step; 203. Protrusion; 2031. First chamfer; 3. Sealing ring; 301. First sealing part; 3011. Second chamfer; 302. Second sealing part; 303. Second step; 304. Compression area; 4. Lower insulating component; 401. Second mounting hole; 5. Upper insulating component; 6. Riveting component. Detailed Implementation

[0029] 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.

[0030] In the description of the embodiments of this invention, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this invention, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces), unless otherwise explicitly specified.

[0031] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0032] In the description of the embodiments of this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0033] The following is combined with Figures 1 to 13 The following describes embodiments of the present invention.

[0034] According to an embodiment of the present invention, a battery cell cover assembly is provided, mainly comprising: a cover plate 1, a terminal post 2, and a sealing ring 3. The cover plate 1 has a first mounting hole 101 extending along the Z direction. The terminal post 2 includes a base 201 and a terminal post body 202 connected along the Z direction. The terminal post body 202 passes through the first mounting hole 101 and extends beyond the upper surface of the cover plate 1. A protrusion 203 is provided on the outer peripheral wall of the end of the terminal post body 202 extending beyond the first mounting hole 101, and the protrusion 203 extends circumferentially along the terminal post body 202 in the XY plane. The sealing ring 3 is sleeved on the outer side of the terminal post body 202 in the XY plane and sandwiched between the cover plate 1 and the base 201. Along the Z direction, the sealing ring 3 is also located between the protrusion 203 and the base 201.

[0035] As can be seen, the battery cell cover assembly provided in this embodiment of the invention has a protrusion 203 on the outer peripheral wall of the end of the electrode body 202 that extends out of the first mounting hole 101, and the sealing ring 3 is placed between the protrusion 203 and the base 201. When the cover 1 is assembled, the protrusion 203 can effectively protect the top of the sealing ring 3, significantly reducing the risk of crushing or folding the top of the sealing ring 3 when the cover 1 is pressed down, thereby improving the sealing effect and also helping to improve the reliability and service life of the battery cell.

[0036] Specifically, the Z direction is also the thickness direction of cover plate 1, such as... Figure 1 and Figure 3 As indicated by arrow Z. The X direction is also the length direction of cover plate 1, as shown in the image. Figure 1 and Figure 2 As indicated by arrow X, the Y direction is also the width direction of cover plate 1, as shown in the figure. Figure 1 and Figure 2 As indicated by the arrow Y. The XY plane is the plane formed by the X and Y directions.

[0037] It should be noted that the material of the sealing ring 3 is not limited in the embodiments of the present invention. Any existing material can be selected as needed. For example, the sealing ring 3 is made of fluororubber with a hardness value of 70±10 A (GB / T531.1-2008), tensile strength ≥10 MPa (GB / T528-2009), and elongation at break ≥175% (GB / T528-2009).

[0038] In one embodiment, such as Figure 6 and Figure 7 As shown, the length of the protrusion 203 along the X and / or Y directions is L1, which satisfies 0.03 mm ≤ L1 ≤ 0.05 mm.

[0039] And / or, along the Z direction, the height of the protrusion 203 is H1, satisfying 0.5 mm ≤ H1 ≤ 2 mm.

[0040] By controlling the length L1 and / or height H1 of the protrusion 203 within a suitable range, it is ensured that the protrusion 203 has sufficient structural strength and an effective protective area. If L1 is too small, the protective area of ​​the protrusion 203 on the sealing ring 3 will be too small, and the risk of the sealing ring 3 being crushed or folded will still be relatively high. If L1 is too large, it will be inconvenient to assemble the sealing ring 3, affecting assembly efficiency, and the protrusion 203 will occupy too much space. If H1 is too small, the structural strength of the protrusion 203 will be weak, and the protrusion 203 will be prone to deformation or even breakage during assembly, resulting in poor reliability. If H1 is too large, it will be inconvenient to assemble the sealing ring 3, affecting assembly efficiency, and the protrusion 203 will occupy too much space.

[0041] In one embodiment, such as Figure 5 , Figure 6 and Figure 7 As shown, the pole body 202 includes a first pole 2021 and a second pole 2022. One end of the second pole 2022 is connected to the first pole 2021, and the other end is connected to the base 201. The projection of the first pole 2021 along the XY plane falls into the projection of the second pole 2022 along the XY plane, so that a first step 2023 is formed between the first pole 2021 and the second pole 2022. The protrusion 203 is provided on the outer peripheral wall of the second pole 2022 and is connected to the first step 2023 through a first chamfer 2031.

[0042] Along the X and / or Y directions, the length of the first chamfer 2031 is L8, which satisfies 0.2 mm ≤ L8 ≤ 0.3 mm.

[0043] And / or, along the Z direction, the length of the first chamfer 2031 is L9, satisfying 0.2 mm ≤ L9 ≤ 0.3 mm.

[0044] The first column 2021 is used to rivet the riveting component 6 to fix the cover plate 1 to the pole post 2. The second column 2022 is used to install the sealing ring 3. The first step 2023 is used for limiting the installation of the riveting component 6. A first chamfer 2031 is provided at the protrusion 203 and the first step 2023 to form a smooth transition surface so that the sealing ring 3 can be fitted into the second column 2022 in the Z direction. This facilitates the assembly of the sealing ring 3 and also prevents the sealing ring 3 from being scratched by the protrusion 203.

[0045] It should be noted that after the first chamfer 2031 is set at the first step 2023, the height H1 of the protrusion 203 refers to the distance along the Z direction between the bottom of the protrusion 203 and the bottom end of the inclined surface where the first chamfer 2031 is located. Figure 7 As shown.

[0046] Furthermore, in one embodiment, such as Figure 8 , Figure 9 and Figure 10 As shown, the sealing ring 3 includes a first sealing part 301 and a second sealing part 302 connected along the Z direction. The first sealing part 301 is sandwiched between the cover plate 1 and the base 201. The second sealing part 302 passes through the first mounting hole 101 and is sleeved on the outer side of the second column 2022 in the XY plane. A second chamfer 3011 is provided on the inner circumferential side of the first sealing part 301 away from the second sealing part 302.

[0047] Along the X and / or Y directions, the length of the second chamfer 3011 is L10, satisfying 0.2 mm ≤ L10 ≤ 0.3 mm, and L10 ≥ L8.

[0048] And / or, along the Z direction, the length of the second chamfer 3011 is L11, satisfying 0.2 mm ≤ L11 ≤ 0.3 mm, L11 ≥ L9.

[0049] The first sealing part 301 is used to seal the cover plate 1 and the pole post 2, and the second sealing part 302 is used to insulate the cover plate 1 and the pole post 2. A second chamfer 3011, not less than the first chamfer 2031, is formed on the inner circumferential side of the first sealing part 301 to form a guiding slope, so that the sealing ring 3 can be more smoothly fitted into the second post 2022.

[0050] In one embodiment, such as Figure 3 As shown, along the Z direction, the second sealing part 302 extends out of the first mounting hole 101, and the length of the second sealing part 302 extending beyond the first mounting hole 101 is L2, satisfying 0.6 mm ≤ L2 ≤ 0.8 mm. The larger the length L2 of the second sealing part 302 extending out of the first mounting hole 101, the greater the risk that the second sealing part 302 will be crushed or folded by the cover plate 1 during assembly. By controlling L2 within a suitable range, the risk of the second sealing part 302 being crushed or folded by the cover plate 1 can be further reduced.

[0051] In one embodiment, such as Figure 1 , Figure 2 and Figure 3 As shown, the cell cover assembly also includes an upper insulating component 5 and a riveting component 6. An installation groove is formed on the upper surface of the cover 1 along the periphery of the first mounting hole 101. The upper insulating component 5 is fitted over the electrode post 2, with its lower end located within the installation groove. The installation groove is used for the installation and positioning of the upper insulating component 5. The upper surface of the upper insulating component 5 also has a receiving groove for installing the riveting component 6. The riveting component 6 is fitted over the first post 2021 and located between the upper insulating component 5 and the electrode post 2. The electrode post 2 is fixed to the cover 1 by riveting with the riveting component 6. At this time, L2 can be the distance along the Z direction between the bottom of the installation groove and the top of the second sealing part 302. The upper insulating component 5 is used for insulation of the electrode post 2, preventing short circuits caused by contact between the electrode post 2 and the cover 1. After the upper insulating component 5 and the riveting component 6 are assembled and riveted, they press against the second sealing part 302 to further improve the sealing effect.

[0052] Furthermore, in one embodiment, such as Figure 3 As shown, the second sealing part 302 has an installation gap between its outer peripheral wall in the XY plane and the wall of the first mounting hole 101. The length of this installation gap, L3, along the X and / or Y directions, satisfies 0.25 mm ≤ L3 ≤ 0.6 mm. By controlling the length of the installation gap between the outer peripheral wall of the second sealing part 302 and the wall of the first mounting hole 101 within a suitable range, sufficient installation space can be provided when assembling the cover plate 1, reducing the risk of contact between the cover plate 1 and the second sealing part 302, thereby further reducing the risk of the second sealing part 302 being crushed or folded by the cover plate 1.

[0053] In one embodiment, such as Figure 3 and Figure 8As shown, the cross-sectional area of ​​the first sealing part 301 in the XY plane is larger than that of the second sealing part 302 in the XY plane, so that a second step 303 is formed at the connection between the first sealing part 301 and the second sealing part 302. The second step 303 has a compression area 304 formed after being pressed against the lower surface of the cover plate 1. The second step 303 is used for limiting the installation of the sealing ring 3.

[0054] Furthermore, along the X and / or Y directions, the width of the compression region 304 is L4, satisfying L4≥1 mm.

[0055] By controlling the lower limit of the width L4 of the compression zone 304, sufficient compression is ensured for the first sealing part 301, avoiding sealing failure and leakage risks caused by insufficient compression. If L4 is too small, the compression ratio of the sealing ring 3 will be insufficient, which can easily lead to sealing failure and leakage of the cover plate 1.

[0056] In one embodiment, such as Figure 1 , Figure 3 and Figure 13 As shown, the battery cell cover assembly also includes a lower insulating member 4 disposed on the lower surface of the cover 1 along the Z direction. The lower insulating member 4 has a second mounting hole 401 corresponding to the first mounting hole 101. The second column 2022 passes through the second mounting hole 401, and the first sealing part 301 is located between the second column 2022 and the lower insulating member 4.

[0057] Furthermore, the first sealing part 301 has an assembly gap between its outer peripheral wall in the XY plane and the hole wall of the second mounting hole 401. The width of the assembly gap along the X direction and / or Y direction is L5, which satisfies 0.2 mm ≤ L5 ≤ 0.5 mm.

[0058] By reserving an appropriate assembly gap between the first sealing part 301 and the lower insulating part 4, space is provided to accommodate the expansion of the sealing ring 3 under pressure, preventing excessive compression of the lower insulating part 4 due to the expansion of the sealing ring 3, and preventing the lower insulating part 4 from expanding. If L5 is too small, the sealing ring 3 will be compressed and expanded after assembly, squeezing the lower plastic, which will cause the width of the lower plastic at the pole post 2 position to exceed the upper limit.

[0059] Specifically, the bottom of the lower insulating member 4 is provided with a placement groove, the base 201 is disposed in the placement groove, and a second mounting hole 401 is opened at the bottom of the placement groove, through which the second column 2022 passes. Part of the lower insulating member 4 is also sandwiched between the base 201 and the cover plate 1.

[0060] In one embodiment, such as Figure 3 , Figure 12 and Figure 13As shown, the outer peripheral wall of the second column 2022 and the inner peripheral wall of the sealing ring 3 are in a zero-clearance fit, that is, the rod diameter L6 of the second column 2022 is equal to the inner diameter L7 of the sealing ring 3. The zero-clearance fit between the second column 2022 and the sealing ring 3 eliminates the radial movement space between them, improves the positioning accuracy of the second column 2022 and the sealing ring 3, and reduces the risk that the cover plate 1 will press against the second sealing part 302 of the sealing ring 3 due to the positioning accuracy problem of the pole post 2 during assembly.

[0061] In one embodiment, such as Figure 3 , Figure 9 and Figure 12 As shown, to improve the current-carrying capacity of the pole 2, the pole 2 can be an elliptical pole, that is, the cross-sections of the first pole 2021 and the second pole 2022 are both elliptical. The diameter of the second pole 2022 along the Y direction is L6, and correspondingly, the sealing ring 3 is an elliptical ring, and the inner diameter of the sealing ring 3 along the Y direction is L7.

[0062] Of course, in other embodiments, the pole post 2 can also be selected as a cylindrical or rectangular post or other conventional shape as needed.

[0063] The assembly process of the battery cell cover assembly according to an embodiment of the present invention is as follows: First, fix the pole post 2 onto the clamp. Then, fit the sealing ring 3 onto the second column 2022 of the pole post 2, so that the base 201 supports the first sealing part 301. Next, fit the cover plate 1 onto the sealing ring 3, and use the cover plate 1 and the base 201 together to clamp the first sealing part 301. Since the outer peripheral wall of the second column 2022 is provided with protrusions 203, it can effectively protect the second sealing part 302 of the sealing ring 3, thereby significantly reducing the risk that the second sealing part 302 of the sealing ring 3 will be crushed or folded by the cover plate 1 during the pressing process. It should be noted that, in this embodiment of the invention, the length L3 of the installation gap is obtained based on the dimensions of the outer peripheral wall of the second sealing part 302 and the diameter of the first mounting hole 101, and is the installation gap after the cover plate 1 is assembled but before the riveting part 6 and the upper insulating part 5 are installed. After the riveting part 6 and the upper insulating part 5 are installed and riveted, the length L3 of the installation gap will be further reduced.

[0064] The process parameters of the battery cell cover assembly of the present invention will be further described in detail below with reference to specific embodiments. These examples should not be construed as limiting the scope of protection claimed by the present invention.

[0065] Example 1: The diameter L6 of the second column 2022 is 4.5 mm, the inner diameter L7 of the sealing ring 3 is 4.5 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.6 mm, the length L3 of the mounting gap is 0.25 mm, the width L4 of the compression area 304 is 1 mm, and the width L5 of the assembly gap is 0.2 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.03 mm, and along the Z direction, the height H1 of the protrusion 203 is 0.5 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.2 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.2 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.2 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.2 mm.

[0066] Example 2: The diameter L6 of the second column 2022 is 4.5 mm, the inner diameter L7 of the sealing ring 3 is 4.5 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.65 mm, the length L3 of the mounting gap is 0.35 mm, the width L4 of the compression area 304 is 1.15 mm, and the width L5 of the assembly gap is 0.25 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.04 mm, and along the Z direction, the height H1 of the protrusion 203 is 0.6 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.2 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.2 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.2 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.2 mm.

[0067] Example 3: The diameter L6 of the second column 2022 is 4.5 mm, the inner diameter L7 of the sealing ring 3 is 4.5 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.7 mm, the length L3 of the mounting gap is 0.4 mm, the width L4 of the compression area 304 is 1.2 mm, and the width L5 of the assembly gap is 0.3 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.05 mm, and along the Z direction, the height H1 of the protrusion 203 is 0.8 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.2 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.2 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.2 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.2 mm.

[0068] Example 4: The diameter L6 of the second column 2022 is 4.8 mm, the inner diameter L7 of the sealing ring 3 is 4.8 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.75 mm, the length L3 of the mounting gap is 0.45 mm, the width L4 of the compression area 304 is 1.25 mm, and the width L5 of the assembly gap is 0.35 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.03 mm, and along the Z direction, the height H1 of the protrusion 203 is 1 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.2 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.2 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.2 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.2 mm.

[0069] Example 5: The diameter L6 of the second column 2022 is 4.8 mm, the inner diameter L7 of the sealing ring 3 is 4.8 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.8 mm, the length L3 of the mounting gap is 0.5 mm, the width L4 of the compression area 304 is 1.3 mm, and the width L5 of the assembly gap is 0.4 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.04 mm, and along the Z direction, the height H1 of the protrusion 203 is 1.2 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.2 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.2 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.25 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.25 mm.

[0070] Example 6: The diameter L6 of the second column 2022 is 4.8 mm, the inner diameter L7 of the sealing ring 3 is 4.8 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.6 mm, the length L3 of the mounting gap is 0.55 mm, the width L4 of the compression area 304 is 1.1 mm, and the width L5 of the assembly gap is 0.45 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.05 mm, and along the Z direction, the height H1 of the protrusion 203 is 1.3 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.25 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.25 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.25 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.25 mm.

[0071] Example 7: The second column 2022 has a rod diameter L6 of 5 mm, the sealing ring 3 has an inner diameter L7 of 5 mm, the second sealing part 302 extends 0.65 mm beyond the first mounting hole 101 by a length L2, the mounting gap length L3 is 0.6 mm, the compression area 304 has a width L4 of 1.15 mm, and the assembly gap width L5 is 0.5 mm. Along the X and / or Y directions, the protrusion 203 has a length L1 of 0.03 mm, and along the Z direction, the protrusion 203 has a height H1 of 1.4 mm. Along the X and / or Y directions, the first chamfer 2031 has a length L8 of 0.25 mm, and along the Z direction, the first chamfer 2031 has a length L9 of 0.25 mm. Along the X and / or Y directions, the second chamfer 3011 has a length L10 of 0.25 mm, and along the Z direction, the second chamfer 3011 has a length L11 of 0.25 mm.

[0072] Example 8: The second column 2022 has a rod diameter L6 of 5 mm, the sealing ring 3 has an inner diameter L7 of 5 mm, the second sealing part 302 extends 0.7 mm beyond the first mounting hole 101 by a length L2, the mounting gap length L3 is 0.4 mm, the compression area 304 has a width L4 of 1.2 mm, and the assembly gap width L5 is 0.3 mm. Along the X and / or Y directions, the protrusion 203 has a length L1 of 0.04 mm, and along the Z direction, the protrusion 203 has a height H1 of 1.5 mm. Along the X and / or Y directions, the first chamfer 2031 has a length L8 of 0.25 mm, and along the Z direction, the first chamfer 2031 has a length L9 of 0.25 mm. Along the X and / or Y directions, the second chamfer 3011 has a length L10 of 0.3 mm, and along the Z direction, the second chamfer 3011 has a length L11 of 0.3 mm.

[0073] Example 9: The diameter L6 of the second column 2022 is 5.5 mm, the inner diameter L7 of the sealing ring 3 is 5.5 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.75 mm, the length L3 of the mounting gap is 0.35 mm, the width L4 of the compression area 304 is 1.25 mm, and the width L5 of the assembly gap is 0.35 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.05 mm, and along the Z direction, the height H1 of the protrusion 203 is 2 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.3 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.3 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.3 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.3 mm.

[0074] Example 10: The diameter L6 of the second column 2022 is 5.5 mm, the inner diameter L7 of the sealing ring 3 is 5.5 mm, the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.8 mm, the length L3 of the mounting gap is 0.3 mm, the width L4 of the compression area 304 is 1.3 mm, and the width L5 of the assembly gap is 0.45 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.05 mm, and along the Z direction, the height H1 of the protrusion 203 is 1.8 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.3 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.3 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.3 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.3 mm.

[0075] Comparative Example 1: The diameter L6 of the second column 2022 is 4.8 mm, the inner diameter L7 of the sealing ring 3 is 4.8 mm, and the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.85 mm, which is greater than 0.8 mm. The length L3 of the mounting gap is 0.55 mm, the width L4 of the compression area 304 is 1.1 mm, and the width L5 of the assembly gap is 0.45 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.05 mm, and along the Z direction, the height H1 of the protrusion 203 is 1.3 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.25 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.25 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.25 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.25 mm.

[0076] Comparative Example 2: The diameter L6 of the second column 2022 is 4.5 mm, the inner diameter L7 of the sealing ring 3 is 4.5 mm, and the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.5 mm. The length L3 of the mounting gap is 0.2 mm, which is less than 0.25 mm. The width L4 of the compression area 304 is 1.1 mm, and the width L5 of the assembly gap is 0.2 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.03 mm, and along the Z direction, the height H1 of the protrusion 203 is 1.4 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.25 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.25 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.25 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.25 mm.

[0077] Comparative Example 3: The diameter L6 of the second column 2022 is 4.5 mm, the inner diameter L7 of the sealing ring 3 is 4.5 mm, and the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.7 mm. The length L3 of the mounting gap is 0.4 mm. The width L4 of the compression area 304 is 1.2 mm, and the width L5 of the assembly gap is 0.3 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.06 mm, greater than 0.05 mm. Along the Z direction, the height H1 of the protrusion 203 is 0.8 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.2 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.2 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.2 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.2 mm.

[0078] Comparative Example 4: The diameter L6 of the second column 2022 is 5.5 mm, the inner diameter L7 of the sealing ring 3 is 5.5 mm, and the length L2 of the second sealing part 302 extending beyond the first mounting hole 101 is 0.75 mm. The length L3 of the mounting gap is 0.35 mm. The width L4 of the compression area 304 is 1.25 mm, and the width L5 of the assembly gap is 0.35 mm. Along the X and / or Y directions, the length L1 of the protrusion 203 is 0.05 mm. Along the Z direction, the height H1 of the protrusion 203 is 2.2 mm, greater than 2 mm. Along the X and / or Y directions, the length L8 of the first chamfer 2031 is 0.3 mm, and along the Z direction, the length L9 of the first chamfer 2031 is 0.3 mm. Along the X and / or Y directions, the length L10 of the second chamfer 3011 is 0.3 mm, and along the Z direction, the length L11 of the second chamfer 3011 is 0.3 mm.

[0079] It should be noted that in Examples 1 to 10 and Comparative Examples 1 to 4, 100,000 battery cell cover assemblies were produced. During the assembly process of the battery cell cover assemblies, battery cells that failed the helium test were extracted for water testing and the battery cells were disassembled to observe the appearance of each part of the battery cell cover assembly.

[0080] In Examples 1 to 10, the following conditions are met: 0.03 mm ≤ L1 ≤ 0.05 mm, 0.5 mm ≤ H1 ≤ 2 mm, 0.2 mm ≤ L8 ≤ 0.3 mm, 0.2 mm ≤ L9 ≤ 0.3 mm, 0.2 mm ≤ L10 ≤ 0.3 mm, L10 ≥ L8, 0.2 mm ≤ L11 ≤ 0.3 mm, L11 ≥ L9, 0.6 mm ≤ L2 ≤ 0.8 mm, 0.25 mm ≤ L3 ≤ 0.6 mm, L4 ≥ 1 mm, and 0.2 mm ≤ L5 ≤ 0.5 mm. No leakage was found in the terminal post 2, and disassembly confirmed that the sealing ring 3 was not folded. Therefore, the embodiments of the present invention can avoid the defect of the sealing ring 3 folding during the assembly of the cell cover plate assembly, and can also ensure the sealing effect and prevent the lower insulating component 4 from swelling, resulting in good safety performance of the cell.

[0081] In Comparative Example 1, L2 was higher than the upper limit value of the embodiment of the present invention, and seven cases of leakage of the pole post 2 were found. Disassembly confirmed that the sealing ring 3 was folded over.

[0082] In Comparative Example 2, L3 was lower than the lower limit value of the embodiment of the present invention, and five cases of leakage of the pole post 2 were found. Disassembly confirmed that the sealing ring 3 was folded over.

[0083] In Comparative Example 3, L1 is higher than the upper limit value of the embodiment of the present invention, which makes it inconvenient to assemble the sealing ring 3 and affects the assembly efficiency.

[0084] In Comparative Example 4, H1 is higher than the upper limit value of the embodiment of the present invention, which makes it inconvenient to assemble the sealing ring 3 and affects the assembly efficiency.

[0085] According to an embodiment of the present invention, another aspect provides a battery cell, mainly comprising: a housing, an electrode assembly, and a battery cell cover assembly. The housing has an opening at at least one end. The electrode assembly is disposed within the housing. A cover plate 1 is disposed over the opening and connected to the housing.

[0086] The battery cell provided in this embodiment of the invention has a protrusion 203 on the outer peripheral wall of the end of the electrode body 202 that extends out of the first mounting hole 101, and a sealing ring 3 is disposed between the protrusion 203 and the base 201. When the cover plate 1 is assembled, the protrusion 203 can effectively protect the top of the sealing ring 3, significantly reducing the risk of crushing or folding the top of the sealing ring 3 when the cover plate 1 is pressed down, thereby improving the sealing effect and also helping to improve the reliability and service life of the battery cell.

[0087] This invention does not impose any particular limitations on the type or shape of the battery cell; it can be a blade cell, a prismatic cell, or any other type of cell. The battery cell in this invention can be a lithium-ion cell, a potassium-ion cell, a sodium-ion cell, a lithium-sulfur cell, etc., with lithium-ion cells being particularly preferred. During the charging and discharging process, active ions repeatedly insert and extract between the positive and negative electrode plates. The electrolyte acts as a conductor of ions between the positive and negative electrode plates.

[0088] According to an embodiment of the present invention, in another aspect, a battery pack is also provided, comprising: at least one of the above-described battery cells.

[0089] Since the battery pack includes battery cells and has the same effect as the battery cells, it will not be elaborated on here.

[0090] In the embodiments of the invention, the "battery pack" is formed by combining a certain number of battery cells into a battery module and placing them in a housing in order to protect the battery cells from external impacts, heat, vibration, etc. The battery pack also includes a battery management system (BMS), a thermal management system, an electrical connection system (high-voltage / low-voltage connectors, wiring harnesses, etc.), structural components (casing, brackets, etc.), and protective components, forming a complete functional unit that can directly output electrical energy.

[0091] 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 cell cover assembly, characterized in that, include: The cover plate has a first mounting hole that extends along the Z direction; The pole includes a base and a pole body connected along the Z direction. The pole body passes through the first mounting hole and extends out of the upper surface of the cover plate. The outer peripheral wall of the end of the pole body that extends out of the first mounting hole is provided with a protrusion. The protrusion extends circumferentially along the pole body in the XY plane. A sealing ring is fitted onto the outer side of the pole body in the XY plane and sandwiched between the cover plate and the base; Along the Z-direction, the sealing ring is also located between the protrusion and the base.

2. The cell cover assembly according to claim 1, characterized in that, Along the X and / or Y directions, the length of the protrusion is L1, satisfying 0.03 mm ≤ L1 ≤ 0.05 mm; And / or, along the Z direction, the height of the protrusion is H1, satisfying 0.5 mm ≤ H1 ≤ 2 mm.

3. The cell cover assembly according to claim 2, characterized in that, The pole body includes a first pole and a second pole. One end of the second pole is connected to the first pole, and the other end is connected to the base. The projection of the first pole along the XY plane falls into the projection of the second pole along the XY plane, so that a first step is formed between the first pole and the second pole. The protrusion is provided on the outer peripheral wall of the second pole and is connected to the first step through a first chamfer. Along the X and / or Y directions, the length of the first chamfer is L8, satisfying 0.2 mm ≤ L8 ≤ 0.3 mm; And / or, along the Z direction, the length of the first chamfer is L9, satisfying 0.2 mm ≤ L9 ≤ 0.3 mm.

4. The cell cover assembly according to claim 3, characterized in that, The sealing ring includes a first sealing part and a second sealing part connected along the Z direction. The first sealing part is sandwiched between the cover plate and the base. The second sealing part passes through the first mounting hole and is sleeved on the outer side of the second column in the XY plane. The inner circumferential side of the first sealing part away from the second sealing part has a second chamfer. Along the X and / or Y directions, the length of the second chamfer is L10, satisfying 0.2 mm ≤ L10 ≤ 0.3 mm, L10 ≥ L8; And / or, along the Z direction, the length of the second chamfer is L11, satisfying 0.2 mm ≤ L11 ≤ 0.3 mm, L11 ≥ L9.

5. The cell cover assembly according to claim 4, characterized in that, Along the Z direction, the second sealing part extends out of the first mounting hole, and the length of the second sealing part beyond the first mounting hole is L2, which satisfies 0.6 mm ≤ L2 ≤ 0.8 mm.

6. The cell cover assembly according to claim 4, characterized in that, The second sealing part has an installation gap between its outer peripheral wall in the XY plane and the wall of the first mounting hole. The length of the installation gap along the X and / or Y directions is L3, which satisfies 0.25 mm ≤ L3 ≤ 0.6 mm.

7. The cell cover assembly according to claim 4, characterized in that, The cross-sectional area of ​​the first sealing part in the XY plane is larger than that of the second sealing part in the XY plane, so that a second step is formed at the connection between the first sealing part and the second sealing part. The second step is provided with a compression area formed after being pressed against the lower surface of the cover plate. Along the X and / or Y directions, the width of the compression region is L4, satisfying L4≥1 mm.

8. The cell cover assembly according to claim 4, characterized in that, It also includes a lower insulating member disposed on the lower surface of the cover plate along the Z direction, the lower insulating member having a second mounting hole corresponding to the first mounting hole, the second column passing through the second mounting hole, and the first sealing part being located between the second column and the lower insulating member; The first sealing part has an assembly gap between its outer peripheral wall in the XY plane and the wall of the second mounting hole. The width of the assembly gap is L5 along the X and / or Y directions, which satisfies 0.2 mm ≤ L5 ≤ 0.5 mm.

9. A battery cell, characterized in that, include: The housing has an opening at at least one end; The pole assembly is located within the housing; The cell cover assembly according to any one of claims 1 to 8, wherein the cover is disposed over the opening and connected to the housing.

10. A battery pack, characterized in that, include: At least one battery cell as described in claim 9.

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