Battery cell cover plate assembly, battery cell and battery pack

Abstract

The invention relates to the technical field of batteries, and discloses a battery cell cover plate assembly, a battery cell and a battery pack. The battery cell cover plate assembly comprises a cover plate body, a riveting block and a pole, the riveting block is provided with a pole mounting hole, the pole mounting hole is a stepped hole and comprises an assembling hole section and a riveting hole section, and the assembling hole section and the riveting hole section are both circular holes; the pole is riveted with the riveting block, the pole comprises an assembly column section matched with the assembly hole section and a riveting column section matched with the riveting hole section, and a concave riveting punched hole is formed in the top of the riveting column section; the riveting punched hole is a stepped hole and comprises a first hole section and a second hole section, and the first hole section and the second hole section are both conical holes. In the axial section of the riveting column section, the taper angle of the first hole section of the riveting punched hole is alpha, the taper angle of the second hole section of the riveting punched hole is beta, and alpha and beta meet preset conditions. According to the invention, the problem of insufficient material expansion or excessive material expansion of the circular pole can be solved, and the riveting strength and thrust resistance of the battery cell cover plate assembly and the qualified size of the riveting block are ensured.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a battery cover assembly, a battery cell and a battery pack. Background Art

[0002] In recent years, with the continuous advancement of battery technology and the expansion of its application scope, people's requirements for overall battery performance and safety have gradually increased. As one of the key components of battery packaging, the assembly quality of the cell cover assembly affects the overall performance and safety of the battery.

[0003] The battery cell cover assembly consists of a cover body, a terminal, and a rivet block. The terminal is a key component for connecting to external circuits, while the cover body provides sealing and protection. During assembly, the terminal and cover body are secured together using the rivet block. When riveting the terminal and rivet block, vertical pressure is applied to the terminal from its central axis, causing the top of the terminal to expand and deform, achieving a riveted connection with the rivet block. A common type of terminal used in battery cell cover assemblies is a round terminal.

[0004] The pole is prone to material expansion difficulties during the riveting process. For circular poles, the larger the rod diameter of the assembly column section, the more difficult it is to expand the material, resulting in a gap between the pole and the riveting block, which in turn leads to insufficient riveting strength of the cover body, mechanical strength that cannot meet design requirements, poor thrust resistance, and affecting the reliability and safety of the battery cell. Summary of the Invention

[0005] In view of this, the present invention provides a battery cover assembly, a battery cell and a battery pack to solve the problem of insufficient material expansion of circular poles.

[0006] In a first aspect, the present invention provides a battery cell cover assembly, comprising a cover body, a rivet block and a pole. The cover plate body is provided with an assembly hole, and the cover plate body is a rectangular structure; the rivet block is provided with a pole mounting hole, and the pole mounting hole is a stepped hole, including an assembly hole section and a riveting hole section, and the assembly hole section and the riveting hole section are both circular holes; the pole passes through the assembly hole and the pole mounting hole in sequence and is riveted to the rivet block, and the pole includes an assembly column section that cooperates with the assembly hole section and a riveting column section that cooperates with the riveting hole section, and a concave riveting punching hole is formed on the top of the riveted column section; the riveted punching hole is a stepped hole, including a first hole section and a second hole section that are sequentially arranged in a direction away from the cover plate body, and the first hole section and the second hole section are both tapered holes with a diameter gradually decreasing toward the cover plate body, and a step surface is formed between the first hole section and the second hole section, and within the step surface, the inner diameter of the first hole section is smaller than the inner diameter of the second hole section; in the axial section of the riveted column section, the cone angle of the first hole section of the riveted punching hole is α, and the cone angle of the second hole section of the riveted punching hole is β, which satisfies:

[0007] 10°≤β-α≤35°.

[0008] Beneficial effects: The battery cell cover assembly provided by the present invention designs the riveted punching into a stepped hole structure, and divides the riveted punching into a first hole segment and a second hole segment, both of which are tapered holes. The cone angles of the first hole segment and the second hole segment are set differently, and the angle difference between the cone angle of the first hole segment and the cone angle of the second hole segment is limited to a reasonable range, ensuring that the circular pole can be fully expanded, avoiding the presence of a gap between the pole and the riveted block, ensuring the riveting strength of the battery cell cover assembly, ensuring that it has good thrust resistance, and improving the welding quality between the pole and the riveted block; at the same time, avoiding excessive expansion of the pole, ensuring that the size of the riveted block and the external insulating part meet the requirements.

[0009] In an optional embodiment, the following conditions are also met:

[0010] 35°≤α≤95°,

[0011] 45°≤β≤120°.

[0012] In an optional embodiment, along the thickness direction of the cover plate body, the total depth of the riveted punching is H, in mm, the depth of the second hole segment of the riveted punching is h, in mm, the total thickness of the riveted block is T, in mm, the depth of the riveted hole segment is t, in mm, and the following conditions are satisfied:

[0013]

[0014] t≤H≤T.

[0015] In an optional embodiment, the following conditions are also met:

[0016]

[0017] In an optional embodiment, the diameter of the assembly column segment is D, in mm, and satisfies:

[0018] 6.5mm≤D≤25mm.

[0019] In an optional embodiment, in the axial section of the riveted column segment, the step width between the riveted hole segment and the assembly hole segment is a, in mm, and satisfies:

[0020] 0.35mm≤a≤0.7mm.

[0021] In an optional embodiment, the riveting hole section is a straight-walled hole, or the riveting hole section is a tapered hole with a diameter gradually decreasing toward the assembly hole section.

[0022] In an optional embodiment, the pole also includes a pole base plate, which is connected to the assembly column section, and the pole base plate and the rivet block are respectively arranged on the two side surfaces of the cover body; the battery cell cover assembly also includes a first insulating member and a second insulating member, the rivet block and the first surface of the cover body are insulated and connected by the first insulating member, and the pole base plate and the second surface of the cover body are insulated and connected by the second insulating member.

[0023] In a second aspect, the present invention further provides a battery cell comprising a housing, a pole group, and the cell cover assembly described in the above technical solution. The housing has a receiving cavity and an opening communicating with the receiving cavity; the pole group is disposed in the housing cavity; and the cell cover assembly is disposed in the opening of the housing, encapsulating the pole group within the housing.

[0024] Beneficial Effects: The cell cover assembly is applied to the battery cell to seal the opening of the cell housing, sealing and protecting the internal components of the battery, preventing chemical leakage and the impact of the external environment on the battery. The poles of the cell cover assembly provide a path for the flow of current in and out, ensuring the current conduction during the battery cell's charging and discharging process. The cell cover assembly not only serves as an electrical connection for the battery cell, but also enhances the overall structural stability of the battery cell. It is an important component of the battery cell, ensuring the durability and safety of the battery cell during use.

[0025] Because the battery cell includes a battery cell cover plate assembly and has all the technical effects of the battery cell cover plate assembly, it will not be repeated here.

[0026] In a third aspect, the present invention further provides a battery pack comprising a plurality of battery cells according to the above technical solution, wherein the riveted blocks of adjacent battery cells are welded via a busbar.

[0027] Beneficial effects: Since the battery pack includes battery cells, it has all the technical effects of battery cells and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 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.

[0029] Figure 1 This is a structural schematic diagram of a battery cell cover assembly according to an embodiment of the present invention;

[0030] Figure 2 for Figure 1 A top view of the cell cover assembly shown;

[0031] Figure 3 For the Figure 2 Cross-sectional view at CC;

[0032] Figure 4 for Figure 3 A partial enlarged view of point E in the middle;

[0033] Figure 5 for Figure 3 A cross-sectional view of the cover plate body in the cell cover plate assembly shown;

[0034] Figure 6 for Figure 3 A cross-sectional view of a rivet block in a cell cover assembly is shown;

[0035] Figure 7 for Figure 3 A cross-sectional view of a pole in a cell cover assembly is shown;

[0036] Figure 8 A cross-sectional view of a rivet block in another battery cell cover assembly according to an embodiment of the present invention;

[0037] Figure 9 For Figure 8 A cross-sectional view of a pole with a rivet block shown.

[0038] Description of reference numerals:

[0039] 1. Cover plate body; 101. Assembly hole; 2. Riveted block; 201. Pole mounting hole; 2011. Assembly hole section; 2012. Riveted hole section; 3. Pole; 301. Assembly column section; 302. Riveted column section; 303. Riveted punching hole; 3031. First hole section; 3032. Second hole section; 3033. Step surface; 304. Pole bottom plate; 305. Pole main section; 4. First insulating member; 5. Second insulating member; 6. Sealing ring; 7. Explosion-proof valve; 8. Explosion-proof valve patch. DETAILED DESCRIPTION

[0040] 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.

[0041] The circular pole in the present invention specifically refers to a pole comprising a plurality of pole segments, each of which is a cylindrical structure.

[0042] In the battery cover assembly, the pole and the rivet block are riveted. When the pole and the rivet block are riveted, vertical pressure is applied to the pole from the center axis of the pole. The riveting direction is as follows: Figure 3As shown in the Z direction, the top of the pole expands and deforms, achieving a riveted connection with the rivet block. After riveting, the pole and rivet block are prone to under- or over-expansion. This is especially true for circular poles with large rod diameters. The larger the rod diameter, the more difficult it is to expand the pole, resulting in under-expansion. After riveting, a gap exists between the pole and the rivet block, resulting in insufficient local riveting strength and poor thrust resistance. Furthermore, an excessively large gap between the pole and the rivet block can prevent the two from being welded together.

[0043] If excessive riveting is performed to allow the pole to expand fully, the circular pole will expand excessively, which will cause the riveted block and its external insulating parts to partially expand and deform, resulting in dimensional deviations of the riveted block and its external insulating parts, which will not meet the requirements and affect the overall performance of the battery cover assembly.

[0044] By arranging the riveted punching holes in sections and rationally limiting the taper angles of the two hole sections, the present invention ensures sufficient expansion of the pole, thereby maintaining the riveting strength between the pole and the riveted block, ensuring the thrust resistance of the battery cover assembly, and improving the weld quality between the riveted block and the pole. At the same time, excessive expansion of the pole is avoided, ensuring the proper fit of the riveted block and the external insulator, ensuring the proper dimensions of the riveted block and the external insulator, and guaranteeing the overall performance of the battery cover assembly.

[0045] The following combination Figures 1 to 9 , describing embodiments of the present invention.

[0046] According to an embodiment of the present invention, in a first aspect, a cell cover assembly is provided, comprising a cover body 1, a rivet block 2, and a pole 3. The cover body 1 is provided with an assembly hole 101, and the cover body 1 is a rectangular structure; the rivet block 2 is provided with a pole mounting hole 201, and the pole mounting hole 201 is a stepped hole, comprising an assembly hole section 2011 and a rivet hole section 2012, and both the assembly hole section 2011 and the rivet hole section 2012 are circular holes; the pole 3 passes through the assembly hole 101 and the pole mounting hole 201 in sequence, and is riveted to the rivet block 2, and the pole 3 comprises an assembly column section 301 that cooperates with the assembly hole section 2011 and a rivet column section 302 that cooperates with the rivet hole section 2012, and a concave rivet punching hole 303 is formed on the top of the rivet punching hole 303. The stepped hole includes a first hole section 3031 and a second hole section 3032 sequentially arranged in a direction away from the cover plate body 1. The first hole section 3031 and the second hole section 3032 are both tapered holes with gradually decreasing diameters toward the cover plate body 1. A step surface 3033 is formed between the first hole section 3031 and the second hole section 3032. Within the step surface 3033, the inner diameter of the first hole section 3031 is smaller than the inner diameter of the second hole section 3032. In the axial section of the riveted column section 302, the taper angle of the first hole section 3031 of the riveted punching hole 303 is α, and the taper angle of the second hole section 3032 of the riveted punching hole 303 is β, satisfying the following conditions:

[0047] 10°≤β-α≤35°.

[0048] The cell cover plate assembly provided by the present invention is designed with a stepped hole structure for the riveted punching hole 303, which is divided into a first hole section 3031 and a second hole section 3032. The first hole section 3031 and the second hole section 3032 are both tapered holes. Furthermore, the cone angles of the first hole section 3031 and the second hole section 3032 are differentiated, and the angle difference between the cone angles of the first hole section 3031 and the second hole section 3032 is limited to a reasonable range, ensuring that the circular pole can be fully expanded, avoiding a gap between the pole 3 and the riveted block 2, ensuring the riveting strength of the cell cover plate assembly, ensuring that it has good thrust resistance, and improving the welding quality between the pole 3 and the riveted block 2; at the same time, excessive expansion of the pole 3 is avoided, and the dimensions of the riveted block 2 and the external insulating member meet the requirements.

[0049] The assembly hole section 2011 and the riveting hole section 2012 are both circular holes, and the projection of the pole 3 adapted thereto along its axial direction after riveting is also circular.

[0050] Specifically, under the punching pressure of the riveting punch, the pole 3 expands and deforms toward the riveting hole segment 2012, ultimately forming a riveted column segment 302. A recessed riveting hole 303 is formed at the top of the riveted column segment 302. The riveting hole 303 is a blind hole. In this embodiment, the riveting hole 303 is a two-stage stepped hole, including a first hole segment 3031 and a second hole segment 3032, which are arranged in sequence in a direction away from the cover plate body 1. The first hole segment 3031 and the second hole segment 3032 are both tapered holes with a diameter gradually decreasing toward the cover plate body 1. That is, the side walls of the first hole segment 3031 and the second hole segment 3032 of the riveted hole 303 are both inclined relative to the axis of the pole 3.

[0051] In the axial section of the riveted column segment 302, the cone angle of the first hole segment 3031 of the riveted punch 303 is α, and the cone angle of the second hole segment 3032 of the riveted punch 303 is β. The axial section of the riveted column segment 302 refers to the cross section cut along the axis of the riveted column segment 302, that is, along the Figure 2 The results are as follows: Figure 3 As shown, the enlarged view is Figure 4 The cone angle α of the first hole segment 3031 of the riveted hole 303 is the angle between the two opposite side walls of the first hole segment 3031 of the riveted hole 303 at this time; the cone angle β of the second hole segment 3032 of the riveted hole 303 is the angle between the two opposite side walls of the second hole segment 3032 of the riveted hole 303 at this time.

[0052] The first hole segment 3031 of the riveting punch 303 primarily serves as a positioning and guide, and can be understood as a pre-riveting operation. This initial riveting press opens the riveting position and channel for the subsequent final riveting, allowing for more complete expansion of the terminal 3 during the final riveting, i.e., the riveting press of the second hole segment 3032. Therefore, the taper angle α of the arc edge of the first hole segment 3031 and the taper angle β of the arc edge of the second hole segment 3032 are set differently. The taper angle of the first hole segment 3031 of the riveting punch 303 is slightly smaller, i.e., β is greater than α. Specifically, 10° ≤ β - α ≤ 35°.

[0053] Circular poles with larger rod diameters present difficulties in material expansion, which can easily lead to insufficient material expansion. Therefore, by controlling the difference between the taper angle α of the arc edge of the first hole segment 3031 and the taper angle β of the arc edge of the second hole segment 3032 within the range of 10° to 35°, the circular pole can be fully expanded, avoiding the formation of gaps between the rivet block 2 and the pole 3. This ensures the overall riveting strength of the cell cover assembly, ensures that the thrust resistance performance of the cell cover assembly meets the requirements, and ensures the welding quality between the rivet block 2 and the pole 3. At the same time, it can prevent excessive material expansion of the circular pole, avoid local expansion and deformation of the rivet block 2 and its external insulating parts, and ensure that the dimensions of the rivet block 2 and its external insulating parts meet the requirements.

[0054] In some embodiments, the following conditions are also met:

[0055] 35°≤α≤95°,

[0056] 45°≤β≤120°.

[0057] Specifically, in this embodiment, the cone angle α of the first hole segment 3031 is controlled within the range of 35° to 95°, and the cone angle β of the second hole segment 3032 is controlled within the range of 45° to 120°, which can ensure that the circular pole with a large rod diameter is fully expanded and the riveting is easy to process without increasing the processing difficulty of the riveting process.

[0058] In some embodiments, along the thickness direction of the cover plate body 1, the total depth of the riveted punching hole 303 is H, in mm, the depth of the second hole segment 3032 of the riveted punching hole 303 is h, in mm, the total thickness of the riveted block 2 is T, in mm, and the depth of the riveted hole segment 2012 is t, in mm, satisfying:

[0059]

[0060] t≤H≤T.

[0061] Reference Figure 4Since the second hole section 3032 of the riveting punch 303 is the final rivet, the pole 3 moves toward the riveting hole section 2012 of the riveting block 2 and fills the riveting hole section 2012. Therefore, the ratio of the depth h of the second hole section 3032 of the riveting punch 303 to the depth t of the riveting hole section 2012 is at least 0.5. This can ensure that the pole 3 is fully expanded and there is no gap between the pole 3 and the riveting block 2. At the same time, the ratio of the depth h of the second hole section 3032 of the riveting punch 303 to the depth t of the riveting hole section 2012 does not exceed 1.0. This can prevent excessive expansion of the pole 3 and cause local expansion and deformation of the riveting block 2 and its external insulating member.

[0062] By controlling the ratio of the total depth H of the riveted punch 303 to the depth t of the riveted hole segment 2012 within the range of 1.1 to 1.5, and controlling the ratio of the total depth H of the riveted punch 303 to the total thickness T of the riveted block 2 within the range of 0.6 to 0.9, and t≤H≤T, it is possible to ensure that the pole 3 is fully expanded while avoiding excessive expansion, and to ensure that the riveting process is easy to process without increasing the difficulty of riveting.

[0063] In some embodiments, the diameter of the assembly column section 301 is D, in mm, and satisfies:

[0064] 6.5mm≤D≤25mm.

[0065] The present invention can solve the problem of difficulty in expanding the material of a circular pole, and is particularly suitable for circular poles with large rod diameters. Specifically, the diameter D of the assembly column section 301 of the circular pole is applicable within a range of 6.5 mm to 25 mm.

[0066] Specifically, refer to Figure 7 The assembly column section 301 is a structural segment that mates with the assembly hole section 2011 of the rivet block 2. Furthermore, because the pole 3 also passes through the assembly hole 101 of the cover body 1, the pole 3 is further provided with a pole body section 305 that mates with the assembly hole 101 of the cover body 1. The pole body section 305 is directly connected to the pole base plate 304. In this embodiment, the diameter D of the assembly column section 301 of the pole 3 is smaller than the diameter of the pole body section 305.

[0067] In some embodiments, the following conditions are also met:

[0068]

[0069] Reference Figure 4, Tt can be understood as the height of the assembly hole section 2011 of the riveting block 2. Since the pole 3 moves toward the riveting hole section 2012, the inner diameter of the assembly hole section 2011 is smaller than the inner diameter of the riveting hole section 2012, that is, the inner wall of the assembly hole section 2011 protrudes from the inner wall of the riveting hole section 2012. The protruding part forms a supporting step, which can also be a hanging platform. During the riveting process, it plays a role in supporting the pole 3. By limiting the ratio of the height Tt of the supporting step to the total thickness T of the riveting block 2 to a range of 0.4 to 0.65, the structural strength of the supporting step of the riveting block 2 can be ensured, so that the riveting block 2 will not be deformed during the riveting process. At the same time, the volume of the riveting hole section 2012 of the riveting block 2 is ensured to be reasonable, ensuring that there is sufficient contact area between the riveting block 2 and the pole 3, thereby ensuring sufficient riveting strength between the pole 3 and the riveting block 2.

[0070] In some embodiments, in the axial section of the riveting column segment 302 , the step width between the riveting hole segment 2012 and the assembly hole segment 2011 is a, in mm, and satisfies:

[0071] 0.35mm≤a≤0.7mm.

[0072] Reference Figure 4 Specifically, in the axial section of the riveted post segment 302, the step width between the riveted hole segment 2012 and the assembly hole segment 2011 is a width a. By limiting the width of the hanging platform, the hanging platform's support strength for the pole 3 during the riveting process can be guaranteed, ensuring that the riveted block 2 does not deform. At the same time, sufficient contact area is ensured between the riveted block 2 and the pole 3, thereby ensuring sufficient riveting strength between the pole 3 and the riveted block 2.

[0073] In some embodiments, the rivet hole section 2012 is a straight-walled hole, or the rivet hole section 2012 is a tapered hole with a diameter gradually decreasing toward the assembly hole section 2011 .

[0074] Specifically, the riveting hole section 2012 is a straight-walled hole, that is, the side wall of the riveting hole section 2012 is parallel to the axis of the pole mounting hole 201 , and a straight riveting structure is adopted between the riveting block 2 and the pole 3 .

[0075] The riveting hole section 2012 is a tapered hole with a diameter gradually decreasing toward the assembly hole section 2011 , that is, the side wall of the riveting hole section 2012 is an inclined wall, which forms an acute angle with the axis of the pole mounting hole 201 , and an oblique riveting structure is adopted between the riveting block 2 and the pole 3 .

[0076] In order to verify the technical solution and technical effects of the present invention, specific embodiments and comparative examples are provided below, and thrust tests and appearance inspections of riveted blocks are performed on each case.

[0077] The thrust test is performed using a method known to those skilled in the art. As an example, the thrust test is as follows:

[0078] The testing equipment is a universal material testing machine.

[0079] Test method:

[0080] Randomly select test samples of cell cover assemblies that meet the specifications to ensure that the sample surface is clean and free of scratches or pre-damage.

[0081] Calibrate the force and displacement sensors of the testing machine to ensure data accuracy.

[0082] Place the sampled cell cover assembly in the fixture of the testing machine to ensure that the force point is consistent with the designed position and that the cell cover assembly does not move or tilt during the test.

[0083] Confirm that the fixture is firmly installed, set the loading pressure, and apply thrust to the battery cover assembly along the Z direction, with the thrust directed towards pole 3, and load pole 3 vertically. Set the pressure loading speed.

[0084] Start the tester and apply a thrust to the terminal 3 until the cell cover assembly fails (e.g., the cell cover assembly deforms, or the terminal 3 falls off). The tester records the applied force in real time. The thrust before the cell cover assembly fails is the maximum thrust the cell cover assembly can withstand. Record the maximum thrust value, denoted as F, in Newtons.

[0085] Among them, the appearance inspection of riveting includes checking whether there is obvious deformation or gap in the appearance of each component in the battery cover assembly, and whether the size is qualified.

[0086] The test results of the embodiment are shown in Table 1.

[0087] Table 1

[0088]

[0089] Table 2

[0090]

[0091] By comparing Table 1 and Table 2, it can be seen that in Examples 1 to 9, the difference between the cone angle β of the second hole section 3032 of the riveted punch 303 and the cone angle α of the first hole section 3031 of the riveted punch 303 is in the range of 10° to 35°, the thrust of the battery cover assembly meets the requirements, and is greater than 1500N. After riveting, the components in the battery cover assembly are not deformed and the dimensions are qualified. In Comparative Examples 1 to 4, the value of β-α is less than 10°, the pole material is not fully expanded, the thrust resistance performance test of the battery cover assembly is lower than 1500N, and it is unqualified. The overall riveting strength of the battery cover assembly does not meet the requirements; in Comparative Examples 5 to 8, the value of β-α is greater than 35°, the thrust resistance performance test of the battery cover assembly is qualified, but the pole material is excessively expanded, the rivet block is locally enlarged and deformed, and the width of the rivet block is out of tolerance and unqualified.

[0092] In some embodiments, the pole 3 also includes a pole bottom plate 304, which is connected to the assembly column section 301, and the pole bottom plate 304 and the rivet block 2 are respectively arranged on the two side surfaces of the cover body 1; the battery cell cover assembly also includes a first insulating part 4 and a second insulating part 5, and the rivet block 2 and the first surface of the cover body 1 are insulated and connected by the first insulating part 4, and the pole bottom plate 304 and the second surface of the cover body 1 are insulated and connected by the second insulating part 5.

[0093] Specifically, the first insulating member 4 is provided with a receiving groove that mates with the rivet block 2. The first insulating member 4 is positioned between the rivet block 2 and the cover body 1, with the rivet block 2 positioned within the receiving groove. In this embodiment, the first insulating member 4 is the external insulating member described above. If the straight edge of the pole 3 experiences excessive expansion, it can cause localized expansion and deformation of the rivet block 2 and the first insulating member 4, resulting in dimensional deviations.

[0094] Furthermore, in some embodiments, the first insulating member 4 and the second insulating member 5 are both plastic members. The first insulating member 4 and the second insulating member 5 are used to ensure insulation between the cover body 1 and the rivet block 2, and between the cover body 1 and the terminal 3, thereby preventing short circuits or leakage in the battery cell and improving the safety and reliability of the battery cell.

[0095] The battery cover assembly also includes an explosion-proof valve 7 and an explosion-proof valve patch 8. The cover body 1 has an explosion-proof valve mounting hole, in which the explosion-proof valve 7 is located. The explosion-proof valve patch 8 is attached to the upper surface of the explosion-proof valve mounting hole to protect the explosion-proof valve 7. The explosion-proof valve 7 is designed to quickly explode and release pressure in the event of thermal runaway in the battery cell, thereby ensuring the safety of the battery.

[0096] In some embodiments, the cell cover assembly further includes a sealing ring 6. The pole 3 further includes a pole main section 305 located between the assembly column section 301 and the pole bottom plate 304. The pole main section 305 cooperates with the assembly hole 101 of the cover body 1. The sealing ring 6 is sleeved on the pole main section 305. At least a portion of the sealing ring 6 is located between the pole main section 305 and the assembly hole 101 of the cover body 1, and at least a portion of the sealing ring 6 is located between the pole bottom plate 304 and the cover body 1. In this way, the sealing ring 6 can form a double seal between the pole 3 and the cover body 1 along the axial and radial directions of the pole 3, thereby improving the sealing, reliability, and safety of the battery cell.

[0097] According to an embodiment of the present invention, in a second aspect, a battery cell is provided, comprising a housing, a pole group, and the cell cover assembly of the above embodiment. The housing has a receiving cavity and an opening communicating with the receiving cavity; the pole group is disposed in the receiving cavity of the housing; and the cell cover assembly is disposed in the opening of the housing, encapsulating the pole group within the housing.

[0098] The cell cover assembly is applied to the battery cell to seal the opening of the cell housing, sealing and protecting the internal components of the battery, preventing chemical leakage and the impact of the external environment on the battery. The pole 3 of the cell cover assembly provides a path for current to flow in and out, ensuring current conduction during the battery cell's charging and discharging process. The cell cover assembly not only serves as an electrical connection for the battery cell but also enhances the overall structural stability of the battery cell. It is an important component of the battery cell, ensuring the durability and safety of the battery cell during use.

[0099] Because the battery cell includes a battery cell cover plate assembly and has all the technical effects of the battery cell cover plate assembly, it will not be repeated here.

[0100] According to an embodiment of the present invention, in a third aspect, a battery pack is further provided, comprising a plurality of battery cells according to the above embodiments, wherein the rivet blocks 2 of adjacent battery cells are welded via a busbar.

[0101] Because the battery pack includes battery cells and has all the technical effects of battery cells, they will not be described here.

[0102] 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 battery cover assembly, characterized in that: include: A cover body, wherein the cover body is provided with an assembly hole and has a rectangular structure; A riveting block, wherein the riveting block is provided with a pole mounting hole, wherein the pole mounting hole is a stepped hole, including an assembly hole section and a riveting hole section, wherein both the assembly hole section and the riveting hole section are circular holes; A pole, the pole passes through the assembly hole and the pole mounting hole in sequence and is riveted to the rivet block, the pole includes an assembly column section that cooperates with the assembly hole section and a rivet column section that cooperates with the rivet hole section, and a concave rivet punching hole is formed on the top of the rivet column section; the rivet punching hole is a stepped hole, including a first hole section and a second hole section that are sequentially arranged in a direction away from the cover plate body, the first hole section and the second hole section are both tapered holes with a diameter gradually decreasing toward the cover plate body, a step surface is formed between the first hole section and the second hole section, and within the step surface, the inner diameter of the first hole section is smaller than the inner diameter of the second hole section; In the axial section of the riveted column segment, the cone angle of the first hole segment of the riveted punch is α, and the cone angle of the second hole segment of the riveted punch is β, which satisfies: 10°≤β－α≤35°。 2. The battery cover assembly according to claim 1, characterized in that: Also meets: 35°≤α≤95°， 45°≤β≤120°。 3. The battery cover assembly according to claim 1 or 2, characterized in that: Along the thickness direction of the cover plate body, the total depth of the riveted punching is H, in mm, the depth of the second hole segment of the riveted punching is h, in mm, the total thickness of the riveted block is T, in mm, the depth of the riveted hole segment is t, in mm, satisfying: t≤H≤T.

4. The battery cover assembly according to claim 3, characterized in that: Also meets:

5. The battery cover assembly according to claim 1 or 2, characterized in that: The diameter of the assembly column section is D, in mm, and satisfies: 6.5mm≤D≤25mm.

6. The battery cover assembly according to claim 1 or 2, characterized in that: In the axial section of the riveted column segment, the step width between the riveted hole segment and the assembly hole segment is a, in mm, and satisfies: 0.35mm≤a≤0.7mm.

7. The battery cover assembly according to claim 1 or 2, characterized in that: The riveting hole section is a straight-walled hole, or the riveting hole section is a tapered hole with a diameter gradually decreasing toward the assembly hole section.

8. The battery cover assembly according to claim 1 or 2, characterized in that: The pole further comprises a pole bottom plate, the pole bottom plate is connected to the assembly column section, and the pole bottom plate and the riveting block are respectively provided on both side surfaces of the cover body; The battery cell cover assembly also includes a first insulating member and a second insulating member. The rivet block and the first surface of the cover body are insulated and connected via the first insulating member, and the pole bottom plate and the second surface of the cover body are insulated and connected via the second insulating member.

9. A battery cell, characterized in that: include: a housing, the housing comprising a receiving cavity and an opening communicating with the receiving cavity; a pole group, the pole group being arranged in the accommodating cavity of the shell; The battery cell cover plate assembly according to any one of claims 1 to 8, wherein the battery cell cover plate assembly is arranged at the opening of the shell, and the electrode group is encapsulated in the shell.

10. A battery pack, characterized in that: The invention comprises a plurality of battery cells according to claim 9, wherein the rivet blocks of adjacent battery cells are welded by a busbar.

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