Single battery

Abstract

The single battery comprises a first conductive piece, a second conductive piece, an isolation ring and a battery cell assembly, specifically, the first conductive piece comprises a working surface and an appearance surface which are oppositely arranged, a conductive hole is formed in the first conductive piece, the conductive hole penetrates through the working surface and the appearance surface, and the working surface faces the interior of the single battery; the second conductive piece comprises a riveting column, and a riveting seat and a riveting buckle connected to two ends of the riveting column, the riveting column penetrates through the conductive hole, and the riveting buckle is riveted on the appearance surface; the isolating ring is sleeved on the riveting column, and is clamped between the riveting seat and the working surface; and the battery core assembly is welded with the second conductive piece. The first conductive part and the second conductive part are separated by the isolation ring, so that the first conductive part and the second conductive part are not easy to be subjected to electrochemical corrosion even if being soaked in electrolyte.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a single-cell battery. Background Technology

[0002] To improve the welding performance of the busbar and the individual battery casing, an effective improvement method is to embed terminals made of the same material as the busbar on the cover plate of the individual battery, allowing for homogeneous welding between the terminals and the busbar. However, in the above technical solution, because the terminals and the cover plate are dissimilar metals, and the individual battery is often filled with electrolyte, significant electrochemical corrosion occurs between the cover plate and the terminals. This affects the current-carrying capacity of both the first and second conductive components and also compromises the airtightness of the individual battery casing. Utility Model Content

[0003] One objective of this invention is to provide a single-cell battery that addresses the technical problem of poor welding results due to difficulty in matching parameters when welding the casing and the busbar.

[0004] To achieve the above objectives, the present invention provides a solution as follows: a single-cell battery, comprising a first conductive element, a second conductive element, an insulating ring, and a cell assembly. Specifically, the first conductive element includes a working surface and an external surface disposed opposite to each other, and an electrical conductive hole is formed on the first conductive element, penetrating the working surface and the external surface, with the working surface facing the interior of the single-cell battery; the second conductive element includes a rivet post and rivet seats and rivets connected to both ends of the rivet post, the rivet post passing through the electrical conductive hole, and the rivets being riveted to the external surface; the insulating ring is sleeved on the rivet post, and the rivet seats and the working surface clamp the insulating ring; the cell assembly is welded to the second conductive element.

[0005] In some embodiments of this application, a welding hole is also formed on the second conductive element, and the opening direction of the welding hole is towards the side of the second conductive element away from the cell assembly.

[0006] In some embodiments of this application, the diameter of the conductive hole is D1, the diameter of the welding hole is D2, and 30%≤D2 / D1≤90%.

[0007] In some embodiments of this application, the depth of the welding hole is L1, the projection length of the second conductive element in the thickness direction of the first conductive element is L2, and 50%≤L1 / L2≤90%.

[0008] In some embodiments of this application, the minimum distance between the wall of the welding hole and the outer wall of the second conductive element is L3, where L3 ≥ 0.05 mm.

[0009] In some embodiments of this application, the distance between the bottom of the welding hole and the surface of the second conductive element near the cell assembly is L4, where 0.05mm≤L4≤2mm.

[0010] In some embodiments of this application, the battery cell assembly includes a battery cell and a busbar, the busbar being electrically connected to the battery cell and a second conductive element, respectively.

[0011] In some embodiments of this application, the area of ​​the working surface is S1, the projected area of ​​the contact surface between the second conductive element and the busbar on the working surface is S2, and 20%≤S2 / S1≤90%.

[0012] In some embodiments of this application, the second conductive element is connected to the busbar by a first weld, the projected area of ​​the first weld on the surface of the busbar is S3, the surface area of ​​the busbar on the side closer to the structure of the first conductive element is S4, and S3 / S4≥10%.

[0013] In some embodiments of this application, the second conductive element is welded to the side of the busbar closer to the first conductive element, and the side of the busbar away from the second conductive element is electrically connected to the battery cell.

[0014] In some embodiments of this application, the second conductive element and the busbar are made of the same material.

[0015] In some embodiments of this application, the battery cell assembly includes an electrically connected core and a tab, with the tab and a second conductive element welded together.

[0016] In some embodiments of this application, the second conductive element and the electrode tab are made of the same material.

[0017] In some embodiments of this application, there are multiple conductive holes, and the second conductive element is provided in a corresponding manner to each conductive hole.

[0018] In some embodiments of this application, a plurality of conductive holes are arranged in a circumferential array on the first conductive element.

[0019] In some embodiments of this application, the material of the second conductive element is copper.

[0020] In some embodiments of this application, the single cell further includes a first insulating layer that encloses a second conductive element, and the rivet is at least partially exposed.

[0021] In some embodiments of this application, the material of the first insulating layer is at least one of steel and nickel.

[0022] In some embodiments of this application, the area of ​​the exposed portion of the rivet is S5, the area of ​​the first conductive element near the cell assembly is S1, and 40%≤S5 / S1≤100%.

[0023] In some embodiments of this application, the diameter of the rivet base is D4, the outer diameter of the insulating ring is D5, and 70%≤D4 / D5≤120%.

[0024] In some embodiments of this application, the thickness of the insulating ring is L9, where 0.5 ≤ L9 ≤ 1.5 mm.

[0025] In some embodiments of this application, the outer edge of the end of the rivet away from the rivet seat is provided with an outer chamfer. On any cross section passing through the axis of the rivet, the angle between the outer chamfer and the outer surface is A1, where 10°≤A1≤85°.

[0026] In some embodiments of this application, the distance between the outer edge of the outer chamfer and the appearance surface is L5, the thickness of the rivet is L6, and 0≤L5 / L6≤70%.

[0027] In some embodiments of this application, the thickness of the rivet is L6, the projection length of the second conductive element in the thickness direction of the rivet is L7, and 10%≤L6 / L7≤40%.

[0028] In some embodiments of this application, the diameter of the conductive hole is D1, the outer diameter of the rivet is D3, and 120%≤D3 / D1≤200%.

[0029] In some embodiments of this application, the diameter of the rivet base is D4, where 2mm≤D4≤20mm.

[0030] In some embodiments of this application, the diameter of the conductive hole is D1, the diameter of the rivet base is D4, and 130%≤D4 / D1≤200%.

[0031] In some embodiments of this application, the thickness of the rivet base is L8, where 0.05mm≤L8≤2mm.

[0032] In some embodiments of this application, a riveting hole is also formed on the second conductive member, and the opening direction of the riveting hole is towards the side of the second conductive member away from the battery cell assembly.

[0033] In some embodiments of this application, the edge of the rivet hole is provided with an inner chamfer. On any cross section passing through the axis of the rivet hole, the angle between the inner chamfer plane and the outer surface is A2, where 30°≤A2≤85°.

[0034] In some embodiments of this application, the diameter of the rivet hole is D6, the minimum outer diameter of the second conductive element is D7, and 30%≤D6 / D7≤80%.

[0035] In some embodiments of this application, the first conductive element is further formed with a pressure relief groove, which is recessed on the surface of the first conductive element to avoid the conductive hole.

[0036] In some embodiments of this application, the distance between the edge of the pressure relief groove and the edge of the electrical conductivity hole is L10, where 2mm < L10 < 35mm.

[0037] In some embodiments of this application, the maximum width of the pressure relief groove is L11, where 0.05mm≤L11≤5mm.

[0038] In some embodiments of this application, the pressure relief groove is formed on the exterior surface.

[0039] In some embodiments of this application, the distance between the bottom of the pressure relief groove and the working surface is L12, where 0.02mm≤L12≤1.5mm.

[0040] In some embodiments of this application, the included angle between the pressure relief groove and the two groove walls is A3, where 20°≤A3≤90°.

[0041] In some embodiments of this application, the pressure relief groove has a trapezoidal cross-section perpendicular to its extension direction, and the lower base of the trapezoid is located on the surface of the first conductive element.

[0042] In some embodiments of this application, the length of the upper base of the trapezoid is L13, where 0.02mm≤L13≤3mm.

[0043] In some embodiments of this application, the bottom of the pressure relief groove has rounded corners.

[0044] In some embodiments of this application, the radius of the fillet is R1, the maximum width of the pressure relief groove is L11, and 20%≤R1 / L11≤100%.

[0045] In some embodiments of this application, the single cell further includes a second insulating layer covering the surface of the first conductive element facing the cell assembly.

[0046] In some embodiments of this application, the second isolation layer is either a nickel plating layer or an iron alloy plating layer.

[0047] In some embodiments of this application, the second isolation layer is either a PP film or PPS.

[0048] In some embodiments of this application, the area of ​​the first conductive element near the cell assembly is S1, and the projected area of ​​the second insulating layer on the surface of the first conductive element is S8, where 5%≤S8 / S1≤97%.

[0049] In some embodiments of this application, the thickness of the second isolation layer is L14, where 0.05mm≤L14≤2mm.

[0050] In some embodiments of this application, the thickness of the second insulating layer is uniformly distributed across the entire surface of the first conductive element.

[0051] In some embodiments of this application, the thickness of the second insulating layer increases as it approaches the conductive hole.

[0052] In some embodiments of this application, the single battery cell also includes a casing with an opening on one side. A first conductive element blocks the opening of the casing, and the casing together forms an accommodating space. The battery cell assembly is disposed within the accommodating space.

[0053] In some embodiments of this application, the single cell further includes a second weld, through which the first conductive element and the cover plate are connected.

[0054] In some embodiments of this application, the height of the second weld protruding from the surface of the housing is H3, where 0mm≤H3≤3mm.

[0055] In some embodiments of this application, the width of the second weld is L15, where 2mm ≤ L15 ≤ 6mm.

[0056] In some embodiments of this application, the first conductive element includes a first plate, a second plate, and a third plate. A conductive hole is formed in the first plate, the third plate is wrapped around the first plate, the housing is connected to the third plate, and the opposite ends of the second plate are respectively connected to the first plate and the third plate. The first plate and the second plate are embedded in the opening of the housing.

[0057] In some embodiments of this application, the first plate and the second plate are connected by an arc.

[0058] In some embodiments of this application, the radius of the arc is R2, where 0.1mm ≤ R2 ≤ 2mm.

[0059] In some embodiments of this application, the radius of the arc is R2, the thickness of the first plate is L16, and 20%≤R2 / L16≤100%.

[0060] In some embodiments of this application, there is an assembly gap between the second plate and the housing.

[0061] In some embodiments of this application, the width of the assembly gap is L17, where 0.1mm≤L17≤0.5mm.

[0062] The beneficial effects of this utility model are as follows:

[0063] A sealing ring is sandwiched between the rivet base of the second conductive component and the working surface of the first conductive component. This prevents direct contact between the parts of the first and second conductive components exposed to the electrolyte environment, thus eliminating the conditions for electrochemical corrosion between them. In this case, the first and second conductive components can be made of different materials, allowing for homogeneous welding of the second conductive component and the busbar of the battery cell assembly. This results in better weld quality and prevents electrochemical corrosion between the first and second conductive components from affecting the lifespan of the individual battery cells. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0065] Figure 1 This is a schematic diagram of the overall structure of a single battery provided in an embodiment of this utility model;

[0066] Figure 2 This is an overall cross-sectional view of a single battery provided in an embodiment of this utility model;

[0067] Figure 3 yes Figure 2 A magnified view of a portion of region A in the middle;

[0068] Figure 4 This is a schematic diagram of the cooperation between the second conductive element and the battery cell assembly provided in another embodiment of the present invention;

[0069] Figure 5 This is a schematic diagram of the cooperation between the second conductive element and the first insulating layer provided in this embodiment of the utility model;

[0070] Figure 6 This is a schematic diagram of the cooperation between the first conductive element, the second conductive element, and the insulating ring provided in this embodiment of the utility model;

[0071] Figure 7 This is a schematic diagram showing the cooperation of the first conductive element, the second conductive element, and the insulating ring provided in this embodiment of the utility model;

[0072] Figure 8 yes Figure 2 A magnified view of a portion of region B in the middle;

[0073] Figure 9 This is a schematic diagram of the cooperation between the pressure relief groove and the second conductive component provided in another embodiment of this utility model;

[0074] Figure 10 This is a schematic diagram of the cooperation between the pressure relief groove and the second conductive component provided in another embodiment of this utility model;

[0075] Figure 11 This is a schematic diagram showing the cooperation of the first conductive element, the second conductive element, the insulating ring, and the second insulating layer provided in this embodiment of the utility model;

[0076] Figure 12 This is a schematic diagram showing the cooperation of the first conductive element, the second conductive element, the insulating ring, and the second insulating layer according to another embodiment of this utility model;

[0077] Figure 13 This is a schematic diagram showing the connection relationship between the first conductive element and the housing provided in this embodiment of the utility model.

[0078] Explanation of icon numbers:

[0079] 10. First conductive component; 11. Conductive hole; 12. Pressure relief groove; 13. First plate; 14. Second plate; 15. Third plate; 20. Second conductive component; 21. Welding hole; 22. Rivet post; 23. Rivet seat; 24. Rivet buckle; 241. Outer chamfer; 242. Riveting hole; 243. Inner chamfer; 30. Battery cell assembly; 31. Battery cell; 311. Core coil; 312. Electrode tab; 32. Busbar; 41. First weld; 42. Second weld; 51. First insulating layer; 52. Second insulating layer; 60. Insulating ring; 70. Housing; 80. Assembly gap. Detailed Implementation

[0080] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0081] To address the problem of electrochemical corrosion within a single battery cell, this invention provides a single battery cell comprising a first conductive element 10, a second conductive element 20, an insulating ring 60, and a cell assembly 30.

[0082] Please see Figures 1 to 3 As shown, Figure 1 This is a schematic diagram of the overall structure of a single battery provided in an embodiment of this utility model; Figure 2 This is an overall cross-sectional view of a single battery provided in an embodiment of this utility model; Figure 3 yes Figure 2 The enlarged view of region A in the middle, together with the above figures, shows the cooperation relationship between the first conductive element 10, the second conductive element 20 and the battery cell 31.

[0083] Specifically, the first conductive component 10 includes a working surface and an outer surface arranged opposite to each other, with the working surface facing the interior of the single cell. The first conductive component 10 has a conductive hole 11 that penetrates the working surface and the outer surface, and the thickness direction of the first conductive component 10 penetrates the first conductive component 10. The second conductive component 20 includes a rivet 22 and rivet seats 23 and rivets 24 connected to both ends of the rivet 22. The rivet 22 passes through the conductive hole 11, and the rivets 24 are riveted to the outer surface. An insulating ring 60 is sleeved on the rivet 22, and the insulating ring 60 is sandwiched between the rivet seats 23 and the working surface. The cell assembly 30 is welded to the second conductive component 20.

[0084] The first conductive element 10 and the second conductive element 20 are designed separately, and they can be configured with different materials according to requirements. For example, the second conductive element 20 is configured with the same material as the area of ​​the cell assembly 30 to which it is welded, optimizing the weld performance between the second conductive element 20 and the cell assembly 30. However, the interior of a single cell is often filled with electrolyte, and the joint between the first conductive element 10 and the second conductive element 20 is immersed in the electrolyte, which will cause severe electrochemical corrosion, resulting in gaps between the first conductive element 10 and the second conductive element 20. This not only affects the current carrying capacity of the first conductive element 10 and the second conductive element 20, but also compromises the airtightness of the single cell casing.

[0085] Compared with the prior art, in this embodiment, an isolation ring 60 is sandwiched between the rivet seat 23 of the second conductive element 20 and the working surface of the first conductive element 10, which are made of dissimilar metals. This reduces the corrosion rate and extends the working life of the single battery.

[0086] The rivet base 23 abuts against the working surface, and the rivet buckle 24 abuts against the outer surface. The formation of the rivet buckle 24 depends on the deformation brought about by the riveting machine. The length of the rivet post 22 depends on the amount of deformation of the rivet buckle 24 during the riveting process. Therefore, the rivet post 22 can adapt to the thickness of the first conductive element 10 and the insulating ring 60, so that the rivet base 23 and the rivet buckle 24 can clamp the first conductive element 10 and the insulating ring 60 better. The slight deformation of the insulating ring 60 after being clamped can also better seal the gap between the first conductive element 10 and the second conductive element 20, and enhance the airtightness of the single cell.

[0087] In some embodiments of this application, a welding hole 21 is also formed on the second conductive element 20, and the opening direction of the welding hole 21 is towards the side of the second conductive element 20 away from the cell assembly 30.

[0088] For clarity, the processing steps of a single battery cell are explained here. Typically, during the processing of a single battery cell, in order to weld the casing and the cell assembly 30, the conductive area of ​​the cell assembly 30 is brought into contact with the casing from the inside. Then, the welding torch is aimed at the corresponding area on the outside of the casing, and by applying voltage and high temperature, the conductive area of ​​the cell assembly 30 that is in contact with the casing is melted through the casing. The molten metal solidifies to form a weld.

[0089] Because the welding process requires melting through the outer shell, the thickness of the outer shell determines the power requirement and penetration of the weld. In this embodiment, the second conductive element 20 is welded to the cell assembly 30. Therefore, the smaller the distance between the outer and inner surfaces of the welding area of ​​the second conductive element 20, the easier the welding will be. By opening welding holes 21 on the second conductive element 20, the welding torch can be brought closer to the area where the cell assembly 30 and the second conductive element 20 are connected. This reduces energy loss during transmission and prevents overheating of the second conductive element 20 during welding, effectively ensuring that the second conductive element 20 retains good electrical and mechanical properties after welding.

[0090] Furthermore, the diameter of the electrical conductivity hole 11 is D1, and the diameter of the welding hole 21 is D2, with 30% ≤ D2 / D1 ≤ 90%.

[0091] The diameter of the welding hole 21 is limited by the diameter of the electrical conductivity hole 11. A larger welding hole 21 allows a larger welding torch to be inserted into it for welding. However, given a fixed size for the electrical conductivity hole 11, an excessively large welding hole 21 would result in an excessively thin wall thickness at the location of the welding hole 21 on the second conductive component 20, affecting its strength and current-carrying capacity. A value of 30%≤D2 / D1≤90% allows for easier insertion of the welding torch into the welding hole 21 while ensuring the strength and current-carrying capacity of the second conductive component 20.

[0092] Optionally, the depth of the welding hole 21 is L1, and the projection length of the second conductive element 20 in the thickness direction of the first conductive element 10 is L2, where 50%≤L1 / L2≤90%.

[0093] The depth of the welding hole 21 is limited by the second conductive element 20. If the welding hole 21 is too shallow, the welding current or heat energy needs to penetrate the thicker bottom of the second conductive element 20, wasting energy and damaging the crystal structure of the second conductive element 20. If the welding hole 21 is too deep, the bottom of the second conductive element 20 will be too thin, posing a risk of excessively rapid heating or even burn-through during the welding process. A value of 50%≤L1 / L2≤90% allows the thickness of the bottom of the second conductive element 20 to be suitable for the welding step.

[0094] It should be noted that the thickness direction mentioned in this embodiment does not necessarily mean that the dimension of the first conductive element 10 in this direction is smaller than its diameter. The description here only indicates that in most existing single-cell batteries, the thickness direction is unambiguously represented by the direction in which the first conductive element 10 is fastened to the housing 70. All dimensional descriptions mentioned below are merely general descriptions in this technical field without additional limitations, and do not imply the absence of special cases. Their specific references should be based on the markings in the corresponding drawings.

[0095] Optionally, the minimum distance between the wall of the welding hole 21 and the outer wall of the second conductive element 20 is L3, where L3 ≥ 0.05 mm.

[0096] The welding hole 21 is preferably coaxially arranged with the second conductive element 20. However, considering the processing accuracy and assembly clearance, there are also application scenarios where the two are eccentrically arranged. Limiting L3 to ≥ 0.05 mm can effectively prevent the distance between the hole wall of the welding hole 21 and the outer wall of the second conductive element 20 from being too close, thus avoiding the second conductive element 20 from being broken down due to insufficient current carrying capacity during the subsequent use of the single cell.

[0097] Optionally, the distance between the bottom of the welding hole 21 and the surface of the second conductive element 20 near the cell assembly 30 is L4, where 0.05mm≤L4≤2mm.

[0098] The dimensions of the second conductive element 20 vary depending on the capacity and design of the individual battery cell. However, the thickness of the bottom of the second conductive element 20, which carries the welding current and heat—that is, the distance between the bottom of the welding hole 21 and the surface of the second conductive element 20 closest to the cell assembly 30—is limited by the welding process and has a specific range of parameters. This range does not change significantly with variations in the second conductive element 20. Calculations show that a value range of 0.05mm ≤ L4 ≤ 2mm is optimal. This range avoids the bottom of the excessively thin second conductive element 20 being burned through, while also preventing energy waste due to an excessively thick bottom.

[0099] In some embodiments of this application, the battery cell assembly 30 includes a battery cell 31 and a busbar 32, the busbar 32 being electrically connected to the battery cell 31 and the second conductive element 20, respectively.

[0100] The busbar 32 can collect the current of the entire cell 31. The second conductive element 20 is welded to the busbar 32. The current of the cell 31 is conducted to the first conductive element 10 through the busbar 32 and the second conductive element 20. During the entire current transmission process, the original largest resistance section is greatly optimized because the second conductive element 20 and the busbar 32 are welded together, which improves the energy efficiency of the single cell.

[0101] Furthermore, the area of ​​the working surface is S1, and the projected area of ​​the contact surface between the second conductive element 20 and the busbar 32 on the working surface is S2, where 20%≤S2 / S1≤90%.

[0102] The larger the contact area between the second conductive element 20 and the busbar 32, the stronger the current conduction capacity between them. However, this positive correlation has a limit due to the limitation of the area of ​​the busbar 32. 20%≤S2 / S1≤90% is a numerical range that can provide a more intuitive performance optimization from increasing the area of ​​the busbar 32 and the second conductive element 20.

[0103] It should be noted that the projected area here refers to the area of ​​the largest shape that the structure can enclose on the corresponding plane. For structures with internal holes, the projected area should be defined by the outer edge of the projected shape.

[0104] Optionally, the second conductive element 20 is connected to the busbar 32 via a first weld 41. The projected area of ​​the first weld 41 on the surface of the busbar 32 is S3, and the surface area of ​​the busbar 32 on the side closer to the structure of the first conductive element 10 is S4, where S3 / S4≥10%.

[0105] The larger the proportion of the first weld 41, the more stable the connection between the busbar 32 and the second conductive element 20. Especially in technical solutions that require stabilizing the position of the cell assembly 30 through the first weld 41, the cross-sectional area of ​​the first weld 41 directly affects whether the cell assembly 30 can maintain its connection with the second conductive element 20. S3 / S4≥10% is the preferred numerical range for maintaining the connection between the second conductive element 20 and the busbar 32.

[0106] Optionally, the second conductive element 20 is welded to the side of the busbar 32 closest to the first conductive element 10, and the side of the busbar 32 furthest from the second conductive element 20 is electrically connected to the battery cell 31.

[0107] The two sides of the busbar 32 are electrically connected to the second conductive element 20 and the battery cell 31, respectively, which can make full use of the surface area of ​​the busbar 32 to increase the current-carrying area and current-carrying capacity.

[0108] Optionally, the second conductive element 20 and the busbar 32 are made of the same material.

[0109] The second conductive component 20 and the busbar 32, which are made of the same material, are similar in welding parameters and flowability, and the effect of homogeneous welding is better.

[0110] Please refer to the following: Figure 4 As shown, Figure 4 This is a schematic diagram of the cooperation between the second conductive element 20 and the battery cell assembly 30 provided in another embodiment of the present invention.

[0111] In some embodiments of this application, the battery cell assembly 30 includes an electrically connected core 311 and a tab 312, with the tab 312 welded to a second conductive element 20.

[0112] This embodiment provides another technical solution. In some technical solutions that do not include the busbar 32, the second conductive element 20 can also be directly electrically connected to the battery cell 31. Specifically, the battery cell 31 includes a core 311 and a tab 312, and the second conductive element 20 and the tab 312 are welded together.

[0113] Furthermore, the second conductive element 20 and the tab 312 are made of the same material.

[0114] Similar to the busbar 32, the second conductive element 20 and the tab 312, which are made of the same material, have similar welding parameters and flowability, resulting in better homogeneous welding.

[0115] In some embodiments of this application, there are multiple conductive holes 11, and the second conductive element 20 is provided in a corresponding manner to each conductive hole 11.

[0116] Multiple conductive holes 11 can disperse the current-carrying area, resulting in better current-carrying performance without changing the total current-carrying area.

[0117] Furthermore, a plurality of conductive holes 11 are arranged in a circumferential array on the first conductive element 10.

[0118] On the one hand, the conductive holes 11 in the circular array can make the current distribution more uniform and optimize the electrical performance of the single cell. On the other hand, the conductive holes 11 in the circular array can also minimize the damage to the mechanical performance of the single cell caused by the opening on the first conductive element 10.

[0119] In some embodiments of this application, the material of the second conductive element 20 is copper.

[0120] The existing battery cell assembly 30, whether it is the type that outputs directly to the outside through the tab 312 or the type that outputs after being combined through the busbar 32, is mostly made of copper at the output end. Making the second conductive element 20 of copper can enhance the welding compatibility between the second conductive element 20 and the battery cell assembly 30, simplify the welding process, and optimize the weld performance.

[0121] It should be noted that in this embodiment, the busbar 32 and the tab 312 are described as output terminals. In a considerable number of cell assemblies 30, the busbar 32 and the tab 312 simultaneously serve as current input terminals. The description here only indicates that the busbar 32 and the tab 312 serve as output terminals during the use of a single battery cell, and does not limit them to only output. This should not be used to limit the scope of protection of this application. The output of the following embodiments should also be understood in this way.

[0122] Please refer to the following: Figure 5 As shown, Figure 5 This is a schematic diagram of the cooperation between the second conductive element 20 and the first insulating layer 50 provided in this embodiment of the utility model.

[0123] Furthermore, the single cell also includes a first insulating layer 51, which encloses a second conductive element 20, with at least a partial exposure of the side of the second conductive element 20 closest to the cell assembly 30.

[0124] In actual processing, the second conductive element 20 and the cell assembly 30 only partially come into contact and are welded. Therefore, with the welded area exposed, setting a first insulating layer 51 to protect other areas of the second conductive element 20 is an effective way to extend its service life. During actual single-cell operation, because the first conductive element 10 and the second conductive element 20 are dissimilar metals, their connection area immersed in the electrolyte will experience electrochemical corrosion. Using the first insulating layer 51 to isolate the first conductive element 10 and the second conductive element 20 can effectively slow down the corrosion rate at their joint.

[0125] Furthermore, the first insulating layer 51 is made of at least one of steel and nickel.

[0126] On the one hand, steel and nickel are both commonly used materials for the first conductive element 10, so electrochemical corrosion is unlikely to occur between the first insulating layer 51 and the first conductive element 10 in direct contact; on the other hand, the joint between the first insulating layer 51 and the second conductive element 20 is sealed between the second conductive element 20 and the battery cell assembly 30, making it difficult for electrolyte to enter and creating an environment conducive to electrochemical corrosion, thus making it difficult for electrochemical corrosion to occur.

[0127] Optionally, the area of ​​the exposed portion of the second conductive element 20 on the side close to the cell assembly 30 is S5, and the area of ​​the first conductive element 10 on the side close to the cell assembly 30 is S1, where 40%≤S5 / S1≤100%.

[0128] Sufficient exposed area of ​​the second conductive element 20 is a prerequisite for ensuring good weldability and current carrying capacity between the second conductive element 20 and the cell assembly 30. When S5 / S1 is less than 40%, the welding effect will be significantly affected. The preferred value of S5 / S1 is 70% or 80%.

[0129] Please refer to the following: Figure 6 and Figure 7 As shown, Figure 6 This is a schematic diagram of the cooperation between the first conductive element 10, the second conductive element 20, and the insulating ring 60 provided in this embodiment of the utility model; Figure 7 This is a schematic diagram showing the cooperation of the first conductive element 10, the second conductive element 20, and the insulating ring 60 provided in this embodiment of the utility model.

[0130] In some embodiments of this application, the outer edge of the end of the rivet 24 away from the rivet seat 23 is provided with an outer chamfer 241. On any cross section passing through the axis of the rivet 24, the angle between the outer chamfer 241 and the outer surface is A1, where 10°≤A1≤85°.

[0131] The outer chamfer 241 effectively prevents scratch damage between the rivet 24 and other components. An excessively large A1 will lead to the formation of new protrusions, rendering the outer chamfer 241 meaningless. Conversely, an excessively small A1 will require the rivet 24 to extend outwards a greater distance to accommodate its thickness. A value between 10° ≤ A1 ≤ 85° is beneficial for structural design and compatible with existing riveting machines. Preferred values ​​for A1 are 45°, 48°, or 54°.

[0132] Specifically, the distance between the outer edge of the outer chamfer 241 and the outer surface is L5, the thickness of the rivet 24 is L6, and 0≤L5 / L6≤70%.

[0133] If the distance between the outer edge of the outer chamfer 241 and the appearance surface is too thick, it will affect the appearance of the individual cells and increase the risk of damage caused by collisions between individual cells in the battery pack. 0≤L5 / L6≤70% is a better value choice, and the optimal value for L5 / L6 is 0%, that is, the outer edge of the outer chamfer 241 is directly attached to the surface of the first conductive element 10.

[0134] Optionally, the thickness of the rivet 24 is L6, and the projected length of the second conductive element 20 in the thickness direction of the rivet 24 is L7, where 10%≤L6 / L7≤40%.

[0135] Although the thickness of the rivet 24 varies depending on the thickness of the material it is riveted to, the thickness of the rivet 24 itself still has some reference value. If the rivet 24 is too small, there is a risk that the rivet 24 will fall off the rivet post 22, resulting in the failure of the connection between the first conductive component 10 and the second conductive component 20. On the other hand, if the rivet 24 is too large, it indicates that there is a defect in the riveting size selection, resulting in a large waste of materials and increasing the redundant weight of the single battery. 10%≤L6 / L7≤40% can ensure the connection effect of the first conductive component 10 and the second conductive component 20 while saving materials as much as possible. The preferred values ​​for L6 / L7 are 20%, 23%, and 25%.

[0136] Optionally, the diameter of the electrical conductivity hole 11 is D1, and the outer diameter of the rivet 24 is D3, where 120%≤D3 / D1≤200%.

[0137] The outer diameter of the rivet 24 determines the riveting strength. Given a fixed size for the electrical conductivity hole 11, a larger outer diameter of the rivet 24 results in a better riveting effect. However, an excessively large rivet 24 will lead to space occupation and material waste. A ratio of 120% ≤ D3 / D1 ≤ 200% is chosen to save material as much as possible while ensuring riveting strength. Provided the machining accuracy allows, D3 / D1 is preferably 128% or 130%.

[0138] Optionally, the diameter of the rivet 23 is D4, where 2mm≤D4≤20mm.

[0139] The diameter of the rivet base 23 determines the pressure-bearing capacity of the second conductive component 20 during the riveting process. This is not affected by the conductive hole 11. An excessively large rivet base 23 will undoubtedly occupy extra space. Therefore, 2mm≤D4≤20mm can avoid damage to the rivet base 23 during the riveting process while saving space as much as possible. D4 is preferably 4mm, 6mm, or 8mm.

[0140] Optionally, the diameter of the electrical conductivity hole 11 is D1, and the diameter of the rivet seat 23 is D4, where 130%≤D4 / D1≤200%.

[0141] The selection of the rivet base 23 should also refer to the electrical conduction hole 11. If the size of the rivet base 23 is too small, there is a risk that the rivet base 23 will be directly inserted into the electrical conduction hole 11 with an interference fit. If the size of the rivet base 23 is too large, it will lead to the occupation of extra space. 130%≤D4 / D1≤200% is the preferred solution. Under the premise that the machining accuracy allows, D4 / D1 is preferably 130%, 132%, or 135%.

[0142] Optionally, the thickness of the rivet base 23 is L8, where 0.05mm≤L8≤2mm.

[0143] The thickness of the rivet base 23 also affects the load-bearing capacity during the riveting process. A rivet base 23 that is too thin is prone to breakage during riveting, while a rivet base 23 that is too large will occupy extra space. Therefore, 0.05mm≤L8≤2mm can avoid damage to the rivet base 23 during riveting while saving space as much as possible. The preferred values ​​for L8 are 0.1mm, 0.5mm, and 1mm.

[0144] Specifically, the diameter of the rivet seat 23 is D4, the outer diameter of the isolation ring 60 is D5, and 70%≤D4 / D5≤120%.

[0145] The diameter of the rivet 23 and the outer diameter of the insulating ring 60 should be as close as possible. A large difference in size will create redundant structures, affecting the space utilization of the individual cells and increasing additional production costs. 70%≤D4 / D5≤120%. Provided the machining accuracy allows, D4 / D5 can be selected as 95%, 98%, or 100%. D4≤D5 can avoid electrochemical corrosion caused by the rivet 23 and the working surface being directly opposite each other.

[0146] Specifically, the thickness of the insulating ring 60 is L9, 0.5≤L9≤1.5mm.

[0147] The thickness of the insulating ring 60 is an important parameter affecting its insulation and sealing performance. If the insulating ring 60 is too thin, it cannot seal well and is easily crushed during riveting. If the insulating ring 60 is too thick, it will take up extra space and affect the space utilization of the single cell.

[0148] In some embodiments of this application, a riveting hole 242 is also formed on the riveted second conductive member 20, and the opening direction of the riveting hole 242 is towards the side of the second conductive member 20 away from the cell assembly 30.

[0149] The setting of the riveting hole 242 is conducive to the insertion of the riveting machine punch and also to the rivet 24 rolling around, reducing the risk of the second conductive component 20 being damaged due to the riveting process.

[0150] Furthermore, the edge of the rivet hole 242 is provided with an inner chamfer 243. On any cross section passing through the axis of the rivet hole 242, the angle between the plane of the inner chamfer 243 and the outer surface is A2, 30°≤A2≤85°.

[0151] The setting of the inner chamfer 243 is beneficial to guide the riveting punch and the riveting hole 242 to align. If A2 is too large, the outer edge of the inner chamfer 243 will be too narrow, resulting in insufficient guiding effect. If A2 is too small, the punch and the inner chamfer 243 will collide and cannot be guided. 30°≤A2≤85° can ensure a good guiding effect. The optimal values ​​for A2 are 40°, 45°, and 48°.

[0152] Optionally, the diameter of the rivet hole 242 is D6, and the minimum outer diameter of the second conductive element 20 is D7, with 30%≤D6 / D7≤80%.

[0153] The diameter of the riveting hole 242 is limited by the outer diameter of the second conductive component 20. A larger riveting hole 242 results in a thinner hole wall, making the riveting process easier. However, an excessively large riveting hole 242 will make the wall thickness of the second conductive component 20 at the location of the riveting hole 242 too thin, affecting the strength and current carrying capacity of the second conductive component 20. A value selection of 30%≤D6 / D7≤80% can ensure the strength and current carrying capacity of the second conductive component 20 while facilitating the riveting process as much as possible. The optimal values ​​for D6 / D7 are 40% or 50%.

[0154] Please refer to the following: Figure 8 As shown, Figure 8 yes Figure 2 A magnified view of a portion of region B in the middle.

[0155] In some embodiments of this application, the first conductive element 10 is further formed with a pressure relief groove 12, which is recessed on the surface of the first conductive element 10 to avoid the conductive hole 11.

[0156] The setting of the pressure relief groove 12 reduces the structural strength of the first conductive element 10 in the corresponding area, making it a structural weakness of the single battery casing. When an accident occurs inside the single battery, such as thermal runaway, causing the internal pressure to rise, the first conductive element 10 in the pressure relief groove 12 area is destroyed, the internal pressure of the single battery is released, and the excessive internal pressure accumulation prevents an explosion.

[0157] Furthermore, the distance between the edge of the pressure relief groove 12 and the edge of the electrical conductivity hole 11 is L10, where 2mm < L10 < 35mm.

[0158] The pressure relief groove 12 is positioned to avoid the conductive hole 11. The distance between the edge of the pressure relief groove 12 and the edge of the conductive hole 11 has an additional impact on the structural strength of the first conductive component 10. If the pressure relief groove 12 and the conductive hole 11 are too close, there is a risk that the pressure relief groove 12 will crack during the assembly of the second conductive component 20. 2mm < L10 < 35mm can ensure the stability of the assembly of the second conductive component 20 while keeping the structure as compact as possible. L10 is preferably 2mm, 3mm, or 5mm.

[0159] Optionally, the maximum width of the pressure relief groove 12 is L11, where 0.05mm≤L11≤5mm.

[0160] The width of the pressure relief groove 12 affects the distribution of weak surfaces in the structure it forms. If the pressure relief groove 12 is too narrow, the pressure relief effect will be weak; if the pressure relief groove 12 is too wide, it will have a significant impact on the structural strength of the first conductive element 10, posing a risk of breakage even under normal use conditions. 0.05mm≤L11≤5mm can satisfy the pressure relief function of the pressure relief groove 12 while ensuring the structural strength of the first conductive element 10. L11 is preferably 0.1mm or 0.2mm.

[0161] Optionally, the pressure relief groove 12 is provided on the exterior surface.

[0162] The pressure relief groove 12 is formed on the outer surface. When the internal pressure of a single cell rises, the working surface of the first conductive element 10 is pressed, and the first conductive element 10 bulges outward. The pressure relief groove 12 tends to open. There is also stress concentration at the bottom of the pressure relief groove 12, which is conducive to the destruction of the first conductive element 10 when the internal pressure of the single cell rises.

[0163] Specifically, the distance between the bottom of the pressure relief groove 12 and the working surface is L12, 0.02mm≤L12≤1.5mm.

[0164] If the distance between the bottom of the pressure relief groove 12 and the working surface is too large, the pressure relief effect will be weak. If the distance between the bottom of the pressure relief groove 12 and the working surface is too small, it will have a significant impact on the structural strength of the first conductive element 10, making it susceptible to breakage even under normal use conditions. 0.02mm≤L12≤1.5mm can satisfy the pressure relief function of the pressure relief groove 12 while ensuring the structural strength of the first conductive element 10. L12 is preferably 0.1mm or 0.15mm.

[0165] It should be noted that the bottom here does not refer to a specific plane, but should be understood as the position within the pressure relief groove 12 closest to the working surface, and should not be used to limit the shape of this embodiment.

[0166] Optionally, the included angle between the pressure relief groove 12 and the two groove walls is A3, where 20°≤A3≤90°.

[0167] The included angle A3 is related to the stress concentration at the bottom of the pressure relief groove 12. When the included angle A3 is too small, the stress concentration at the bottom of the pressure relief groove 12 will be more obvious, which will also cause the first conductive component 10 to crack when the single cell is working normally and generating heat. When the included angle A3 is too large, the width of the widest part of the pressure relief groove 12 will be too large, which will also affect the strength of the first conductive component 10. Through experiments, it can be found that 20°≤A3≤90° is a better included angle range, and A3 is further preferred to be 50° or 60°.

[0168] Please refer to the following: Figure 9 As shown, Figure 9 This is a schematic diagram of the cooperation between the pressure relief groove 12 and the second conductive element 20 provided in another embodiment of this utility model.

[0169] Optionally, the pressure relief groove 12 has a trapezoidal cross-section perpendicular to its extension direction, with the lower base of the trapezoid located on the surface of the first conductive element 10.

[0170] The pressure relief groove 12 has a flat bottom, which can alleviate stress concentration to a certain extent. Under the premise that the depth of the pressure relief groove 12 and the thickness of the first conductive element 10 remain unchanged, the structural strength of the first conductive element 10 is enhanced, and accidental damage to the first conductive element 10 during normal use is avoided.

[0171] Specifically, the length of the upper base of the trapezoid is L13, and 0.02mm≤L13≤3mm.

[0172] If the length of the upper bottom is too small, its effect of relieving stress concentration will not be obvious enough. If the length of the upper bottom is too large, the pressure relief groove 12 will be too wide, which will also affect the structural strength of the first conductive component 10. 0.02mm≤L13≤3mm is the range of values ​​that are not easy to generate stress concentration under the premise of keeping the pressure relief groove 12 relatively narrow. L13 is preferably 1mm.

[0173] Please refer to the following: Figure 10 As shown, Figure 10 This is a schematic diagram of the cooperation between the pressure relief groove 12 and the second conductive element 20 provided in another embodiment of this utility model.

[0174] Optionally, the bottom of the pressure relief groove 12 has rounded corners.

[0175] The pressure relief groove 12 has rounded corners at the bottom, which can alleviate stress concentration to a certain extent. Under the premise that the depth of the pressure relief groove 12 and the thickness of the first conductive component 10 remain unchanged, the structural strength of the first conductive component 10 is enhanced, and accidental damage to the first conductive component 10 during normal use is avoided.

[0176] Specifically, the radius of the rounded corner is R1, the maximum width of the pressure relief groove 12 is L11, and 20%≤R1 / L11≤100%.

[0177] If the radius of the fillet is too small, its effect of relieving stress concentration will not be obvious enough. If the radius of the fillet is too large, the pressure relief groove 12 will be too wide, which will also affect the structural strength of the first conductive component 10. 20%≤R1 / L11≤100% is the range of values ​​that are not easy to generate stress concentration under the premise of keeping the pressure relief groove 12 relatively narrow. R1 / L11 is preferably 50%.

[0178] Please refer to the following: Figure 11 As shown, Figure 11 This is a schematic diagram showing the cooperation of the first conductive element 10, the second conductive element 20, the insulating ring 60, and the second insulating layer 52 provided in this embodiment of the utility model.

[0179] In some embodiments of this application, the single cell also includes a second insulating layer 52, which covers the surface of the first conductive element 10 facing the cell assembly 30.

[0180] The second insulating layer 52 covers the surface of the first conductive element 10 facing the cell assembly 30, at least partially isolating the first conductive element 10 from the electrolyte, thereby slowing down the corrosion rate of the first conductive element 10 and extending the service life of the single cell.

[0181] For example, the second isolation layer 52 is either a nickel plating or an iron alloy plating.

[0182] The nickel or iron alloy plating has electrical conductivity. When the second isolation layer 52 is sandwiched between the first conductive element 10 and the second conductive element 20, the second isolation layer 52 can share part of the current. While isolating the first conductive element 10 and the second conductive element 20 from the area immersed in the electrolyte, it will not significantly affect the current carrying capacity of the single cell.

[0183] For example, the second isolation layer 52 is a PP film or PPS.

[0184] PP film and PPS film are relatively mature protective materials in the field of lithium batteries, with low cost and high processing efficiency.

[0185] Specifically, the area of ​​the first conductive element 10 near the cell assembly 30 is S1, and the projected area of ​​the second insulating layer 52 on the surface of the first conductive element 10 is S8, where 5%≤S8 / S1≤97%.

[0186] The area ratio of the second isolation layer 52 is related to its isolation capacity, and 5%≤S8 / S1≤97% is the optimal range for the experiment.

[0187] Specifically, the thickness of the second isolation layer 52 is L14, 0.05mm≤L14≤2mm.

[0188] The isolation effect of the second isolation layer 52 is positively correlated with its thickness. If the second isolation layer 52 is too thin, there is a risk of it being penetrated. If the second isolation layer 52 is too thick, it will cause additional space occupation and increase production costs. 0.05mm≤L14≤2mm is the range of values ​​that minimizes space occupation while ensuring the isolation effect.

[0189] Specifically, the thickness of the second insulating layer 52 is uniformly distributed across the entire surface of the first conductive element 10.

[0190] The uniformly distributed second isolation layer 52 provides uniform isolation effect, has a simple processing technology, and high production efficiency.

[0191] Please refer to the following: Figure 12 As shown, Figure 12 This is a schematic diagram showing the cooperation of the first conductive element 10, the second conductive element 20, the insulating ring 60, and the second insulating layer 52 provided in another embodiment of this utility model.

[0192] Optionally, the thickness of the second insulating layer 52 increases as it approaches the conductive hole 11.

[0193] There are multiple component contact surfaces near the electrical conductivity hole 11. Applying a thicker second isolation layer 52 to the electrical conductivity hole 11 can effectively enhance the isolation effect in the corresponding area.

[0194] In some embodiments of this application, the thickness of the first conductive element 10 is L11, where 0.5mm≤L11≤2mm.

[0195] The first conductive element 10 carries the functions of conductivity and physical protection. If the first conductive element 10 is too thin, its current carrying capacity and structural strength will be poor. If it is too thick, it will increase the production cost and add weight and volume. 0.5mm≤L11≤2mm is a range of values ​​that can maintain good structural strength and current carrying capacity while minimizing space occupation. L11 is preferably 1mm.

[0196] It should be noted that the first conductive element 10 may be composed of multiple plates spliced ​​together, with each plate located on a different plane. In this case, L11 should be defined as the thickness of the plate rather than the distance between the surfaces of the two plates furthest apart.

[0197] Please refer to the following: Figure 13 As shown, Figure 13 This is a schematic diagram showing the connection relationship between the first conductive element 10 and the housing 70 provided in this embodiment of the utility model.

[0198] In some embodiments of this application, the single battery cell also includes a housing 70, with an opening on one side of the housing 70. A first conductive element 10 blocks the opening of the housing 70 and together with the housing 70 forms an accommodating space, and the cell assembly 30 is disposed within the accommodating space.

[0199] The first conductive element 10 seals the opening and forms an accommodating space with the housing 70. The battery cell assembly 30 is disposed in the accommodating space. This allows the connection of the first conductive element 10 and the second conductive element 20 to be completed first. When the first conductive element 10 is fastened to the housing 70, the second conductive element 20 abuts against the battery cell assembly 30. Alternatively, the assembly of the first conductive element 10, the housing 70 and the battery cell assembly 30 can be completed first, and then the second conductive element 20 can be inserted through the conductive hole 11 and abut against the battery cell assembly 30. The assembly process is more flexible.

[0200] Furthermore, the single cell also includes a second weld 42, through which the first conductive element 10 and the cover plate are connected.

[0201] The first conductive element 10 and the cover plate are connected by the second weld 42, which ensures the connection strength and airtightness of the single battery casing. Moreover, since the second weld 42 undertakes a large part of the connection function, it also indirectly reduces the welding strength requirements between the second conductive element 20 and the cell assembly 30, making it less likely for the second conductive element 20 and the cell assembly 30 to break the circuit.

[0202] Specifically, the height of the second weld 42 protruding from the surface of the shell 70 is H3, where 0mm≤H3≤3mm.

[0203] The portion of the second weld 42 that protrudes from the surface of the casing 70 increases the probability of scratching adjacent individual cells within the battery pack. Therefore, a configuration of 0mm≤H3≤3mm is used to protect the individual cells and extend their lifespan. Where conditions permit, a mill or similar device can be used to make H3 as close to 0mm as possible.

[0204] Specifically, the width of the second weld 42 is L15, where 2mm ≤ L15 ≤ 6mm.

[0205] Because the mechanical properties of the weld are usually greater than those of the base material, a sufficiently large second weld 42 width can ensure the connection strength between the casing 70 and the first conductive element 10. However, due to the limitations of the strength of the casing 70 and the first conductive element 10 themselves, an excessively large second weld 42 cannot improve the overall strength of the single-cell battery casing. 2mm≤L15≤6mm can minimize energy waste while ensuring the connection strength between the first conductive element 10 and the casing 70.

[0206] Optionally, the first conductive element 10 includes a first plate 13, a second plate 14 and a third plate 15. A conductive hole 11 is formed in the first plate 13, the third plate 15 is wrapped around the first plate 13, the housing 70 is connected to the third plate 15, and the opposite ends of the second plate 14 are respectively connected to the first plate 13 and the third plate 15. The first plate 13 and the second plate 14 are embedded in the opening of the housing 70.

[0207] The first plate 13 and the second plate 14 are embedded in the opening of the housing 70. They can be used to position the first conductive component 10 and the housing 70 without molds before the third plate 15 and the housing 70 are welded. This serves as a foolproof structure and avoids the risk of assembly workers installing the first conductive component 10 backwards.

[0208] Furthermore, the first plate 13 and the second plate 14 are connected by an arc.

[0209] When the inner edge of the opening of the housing 70 abuts the arc, there is a spontaneous tendency to guide the first plate 13 and the second plate 14 into the opening. In addition to positioning, it can also guide the assembly and reduce the requirements for alignment accuracy in the assembly process.

[0210] Specifically, the radius of the arc is R2, where 0.1mm ≤ R2 ≤ 2mm.

[0211] A radius that is too small results in a small alignment and guidance area, leading to a weaker guiding effect. Conversely, a radius that is too large will reduce the connection strength between the first plate 13 and the second plate 14. A radius of 0.1mm ≤ R2 ≤ 2mm can achieve the most significant guiding effect while ensuring the structural strength of the first conductive element 10. R2 is preferably 0.5mm or 1mm.

[0212] Specifically, the radius of the arc is R2, the thickness of the first plate 13 is L16, and 20%≤R2 / L16≤100%.

[0213] The radius of the arc is also affected by the thickness of the first plate 13. A radius that is too small results in a smaller alignment and guidance area and a weaker guidance effect, while a radius that is too large will reduce the connection strength between the first plate 13 and the second plate 14. A radius of 20% ≤ R2 / L16 ≤ 100% can achieve the most significant guidance effect while ensuring the structural strength of the first conductive element 10. R2 / L16 is preferably 50%.

[0214] Optionally, there is an assembly gap 80 between the second plate 14 and the housing 70.

[0215] The presence of the assembly gap 80 facilitates the insertion of the first plate 13 and the second plate 14, reducing the alignment accuracy requirements during the assembly process.

[0216] Specifically, the width of the assembly gap 80 is L17, 0.1mm≤L17≤0.5mm.

[0217] An excessively small assembly gap 80 makes it difficult to significantly optimize the assembly process, while an excessively large assembly gap 80 will affect the airtightness between the first conductive component 10 and the housing 70. Therefore, configuring a gap of 0.1mm ≤ L17 ≤ 0.5mm can minimize the alignment accuracy requirement while ensuring airtightness. L17 is preferably 0.4mm or 0.5mm. It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this embodiment of the present invention are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicator will also change accordingly.

[0218] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.

[0219] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0220] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the design concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A single cell, characterized by, The application relates to a single battery, which comprises a first conductive part, a second conductive part, an isolation ring and an electric core assembly. The first conductive part comprises a working surface and an appearance surface arranged oppositely, and an electric guide hole is arranged on the first conductive part and penetrates the working surface and the appearance surface, and the working surface faces the inside of the single battery. The second conductive part comprises a rivet column, a rivet base and a rivet buckle connected to the two ends of the rivet column, the rivet column penetrates the electric guide hole, and the rivet buckle is riveted to the appearance surface. The isolation ring is sleeved on the rivet column, and the rivet base and the working surface sandwich the isolation ring. The second conductive part is welded to the electric core assembly.

2. The cell according to claim 1, wherein A welding hole is further formed on the second conductive part, and the opening direction of the welding hole is away from the side of the second conductive part which is away from the electric core assembly.

3. The cell according to claim 2, wherein The diameter of the electric guide hole is D1, the diameter of the welding hole is D2, and 30%<=D2 / D1<=90%.

4. The cell according to claim 2, wherein The depth of the welding hole is L1, the projection length of the second conductive part in the thickness direction of the first conductive part is L2, and 50%<=L1 / L2<=90%.

5. The cell according to claim 2, wherein The minimum distance between the hole wall of the welding hole and the outer wall of the second conductive part is L3, and L3>=0.05mm.

6. The cell according to claim 2, wherein The distance between the bottom of the welding hole and the surface of the side of the second conductive part which is close to the electric core assembly is L4, and 0.05mm<=L4<=2mm.

7. The cell according to claim 1, wherein The electric core assembly comprises an electric core and a busbar, and the busbar is electrically connected to the electric core and the second conductive part respectively.

8. The cell according to claim 7, wherein The area of the working surface is S1, the projection area of the contact surface between the second conductive part and the busbar on the working surface is S2, and 20%<=S2 / S1<=90%.

9. The cell according to claim 7, wherein The second conductive part is connected to the busbar through a first welding seam, the projection area of the first welding seam on the surface of the busbar is S3, the surface area of the side of the busbar which is close to the structure of the first conductive part is S4, and S3 / S4>=10%.

10. The cell according to claim 7, wherein The second conductive part is welded to the side of the busbar which is close to the first conductive part, and the side of the busbar which is away from the second conductive part is electrically connected to the electric core.

11. The cell according to claim 7, wherein The second conductive part and the busbar are made of the same material.

12. The cell of claim 1 wherein, The electric core assembly comprises an electric core and a tab which are electrically connected, and the tab is welded to the second conductive part.

13. The cell according to claim 12, wherein The second conductive part and the tab are made of the same material.

14. The cell of claim 1 wherein, The second conductive part is correspondingly arranged with the electric guide hole.

15. The cell of claim 14, wherein, Multiple electric guide holes are arranged in a circumferential array on the first conductive part.

16. The cell of claim 1 wherein, The material of the second conductive part is copper.

17. The cell of claim 16, wherein, The single battery further comprises a first isolation layer, the first isolation layer wraps the second conductive part, and the rivet base is at least partially exposed.

18. The cell of claim 17, wherein, The material of the first isolation layer is at least one of steel and nickel.

19. The cell of claim 17, wherein, The area of the exposed part of the rivet base is S5, the area of the side of the first conductive part which is close to the electric core assembly is S1, and 40%<=S5 / S1<=100%.

20. The cell of claim 1 wherein, The diameter of the rivet base is D4, the diameter of the outer diameter of the isolation ring is D5, and 70%<=D4 / D5<=120%.

21. The cell of claim 1 wherein, The thickness of the isolation ring is L9, and 0.5<=L9<=1.5mm.

22. The cell of claim 1 wherein, An outer chamfer is arranged on the outer edge of the rivet away from the rivet seat, and the angle between the outer chamfer and the outer surface is A1 in any cross section passing through the rivet axis, 10°≤A1≤85°.

23. The cell of claim 22, wherein, The distance between the outer edge of the outer chamfer and the outer surface is L5, the thickness of the rivet is L6, and 0≤L5 / L6≤70%.

24. The cell of claim 1 wherein, The thickness of the rivet is L6, the projection length of the second conductive part in the thickness direction of the rivet is L7, and 10%≤L6 / L7≤40%.

25. The cell of claim 1 wherein, The diameter of the electric guide hole is D1, the outer diameter of the rivet is D3, and 120%≤D3 / D1≤200%.

26. The cell of claim 1 wherein, The diameter of the rivet seat is D4, and 2mm≤D4≤20mm.

27. The cell of claim 1 wherein, The diameter of the electric guide hole is D1, the diameter of the rivet seat is D4, and 130%≤D4 / D1≤200%.

28. The cell of claim 1 wherein, The thickness of the rivet seat is L8, and 0.05mm≤L8≤2mm.

29. The cell of claim 1 wherein, The second conductive part is further provided with a riveting hole, and the opening direction of the riveting hole is towards the side of the second conductive part away from the battery cell assembly.

30. The cell of claim 29 wherein, The edge of the riveting hole is provided with an inner chamfer, and the angle between the inner chamfer plane and the outer surface is A2 in any cross section passing through the riveting hole axis, 30°≤A2≤85°.

31. The cell of claim 29 wherein, The diameter of the riveting hole is D6, the minimum outer diameter of the second conductive part is D7, and 30%≤D6 / D7≤80%.

32. The cell of any one of claims 1 to 31, wherein, The first conductive part is further provided with a pressure relief groove, and the pressure relief groove avoids the electric guide hole and is recessed on the surface of the first conductive part.

33. The cell of claim 32 wherein, The distance between the edge of the pressure relief groove and the edge of the electric guide hole is L10, and 2mm<L10<35mm.

34. The cell of claim 32 wherein, The maximum width of the pressure relief groove is L11, and 0.05mm≤L11≤5mm.

35. The cell of claim 32 wherein, The pressure relief groove is opened on the outer surface.

36. The cell of claim 35 wherein, The distance between the bottom of the pressure relief groove and the working surface is L12, and 0.02mm≤L12≤1.5mm.

37. The cell of claim 32 wherein, The included angle of the two opposite groove walls of the pressure relief groove is A3, and 20°≤A3≤90°.

38. The cell of claim 32 wherein, The cross section of the pressure relief groove perpendicular to its extension direction is a trapezoid, and the lower base of the trapezoid is located on the surface of the first conductive part.

39. The cell of claim 38 wherein, The upper base length of the trapezoid is L13, and 0.02mm≤L13≤3mm.

40. The cell of claim 32 wherein, The bottom of the pressure relief groove has a fillet.

41. The cell of claim 40 wherein, The radius of the fillet is R1, the maximum width of the pressure relief groove is L11, and 20%≤R1 / L11≤100%.

42. The cell of any one of claims 1-31, wherein, The single battery further comprises a second isolation layer, and the second isolation layer covers the side surface of the first conductive part towards the battery cell assembly.

43. The cell of claim 42 wherein, The second isolation layer is one of a nickel plating layer or a ferrous alloy plating layer.

44. The cell of claim 42 wherein, The second isolation layer is one of a PP film or PPS.

45. The cell of Claim 42 wherein, The area of the first conductive part close to the battery cell assembly side is S1, the projection area of the second isolation layer on the surface of the first conductive part is S8, and 5%≤S8 / S1≤97%.

46. The cell of claim 42 wherein, The thickness of the second isolation layer is L14, and 0.05mm≤L14≤2mm.

47. The cell of Claim 42 wherein, The thickness of the second isolation layer is uniformly distributed on the surface of the entire first conductive part.

48. The cell of Claim 42 wherein, The thickness of the second isolation layer increases as it approaches the electric guide hole.

49. The cell of any one of claims 1-31, wherein, The monomer battery further comprises a shell, one side of the shell is open, the first conductive piece seals the opening of the shell and the shell to form a containing space, and the cell assembly is arranged in the containing space.

50. The cell of Claim 49 wherein, The monomer battery further comprises a second weld, and the first conductive piece and the shell are connected through the second weld.

51. The cell of Claim 50 wherein, The second weld protrudes from the surface of the shell by a height H3, and 0mm≤H3≤3mm.

52. The cell of Claim 50 wherein, The second weld has a width L15, and 2mm≤L15≤6mm.

53. The cell of Claim 49 wherein, The first conductive piece comprises a first plate, a second plate and a third plate, the electrically conductive hole is arranged on the first plate, the third plate is arranged around the first plate, the shell is connected with the third plate, the opposite ends of the second plate are respectively connected with the first plate and the third plate, and the first plate and the second plate are embedded in the opening of the shell.

54. The cell of Claim 53 wherein, The first plate and the second plate are connected through a circular arc.

55. The cell of Claim 54 wherein, The radius of the circular arc is R2, and 0.1mm≤R2≤2mm.

56. The cell of claim 54 wherein, The radius of the circular arc is R2, the thickness of the first plate is L16, and 20%≤R2 / L16≤100%.

57. The cell of Claim 53 wherein, There is an assembly gap between the second plate and the shell.

58. The cell of Claim 57 wherein, The assembly gap has a width L17, and 0.1mm≤L17≤0.5mm.

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