Conductive member, cover plate assembly, and battery cell

Abstract

The application provides a conductive piece, a cover plate assembly and a battery cell. The conductive piece comprises a terminal and a pole. The terminal has a first surface. The first surface is provided with a first groove. The pole comprises a pole body and a first protrusion arranged at an axial end of the pole body. The first protrusion is embedded in the first groove. The outer surface of the first protrusion and the inner wall of the first groove are mutually engaged. The application embeds the first protrusion in the first groove and makes the outer surface of the first protrusion and the inner wall of the first groove mutually engaged, so as to form a mutually embedded structure between the first protrusion and the inner wall of the first groove, thereby effectively reducing the gap between the pole and the terminal and eliminating the assembly gap. In this way, the resistance of the connecting interface between the pole and the terminal can be reduced, and the overcurrent capacity between the pole and the terminal can be improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a conductive component, a cover plate assembly, and a battery cell. Background Technology

[0002] In related technologies, the battery cell includes a housing, a cover assembly, and an electrode assembly. The cover assembly includes a cover plate, an electrode post passing through the cover plate, a terminal riveted to the outer end of the electrode post, a sealing ring sealing the electrode post and the cover plate, an upper plastic part insulating the terminal from the cover plate, a current collector welded to the inner end of the electrode post, and a lower plastic part insulating the current collector from the cover plate. The cover plate and the housing cover together to define a receiving cavity, in which the electrode assembly is disposed and welded to the current collector. When the electrode post is riveted to the terminal, the terminal has a through hole, the outer end of the electrode post passes through the through hole and is pressed, causing the outer end of the electrode post to deform radially outward, thus engaging with the terminal in the axial direction of the electrode post to form a riveting connection.

[0003] However, the riveting between the pole and the terminal has a lot of gaps, resulting in high resistance at the connection interface between the pole and the terminal, which affects the current carrying capacity between the pole and the terminal. Utility Model Content

[0004] Embodiments of this application provide a conductive element, a cover plate assembly, and a battery cell that can reduce the gap between the terminal and the electrode to lower the resistance of the connection interface between the terminal and the electrode, thereby improving the overcurrent capacity between the terminal and the electrode.

[0005] In a first aspect, embodiments of this application provide a conductive component, which includes a terminal and a post; the terminal has a first surface with a first groove; the post includes a column and a first protrusion disposed at one axial end of the column, the first protrusion being fitted into the first groove; wherein the outer surface of the first protrusion engages with the inner wall of the first groove. This creates an engaging structure between the first protrusion and the inner wall of the first groove, effectively reducing the gap between the post and the terminal and eliminating assembly gaps. Consequently, the resistance of the connection interface between the post and the terminal is reduced, thereby improving the current-carrying capacity between the post and the terminal.

[0006] In some embodiments, a second groove is provided on the side of the terminal opposite to the first groove, and a second protrusion is formed at the bottom of the second groove, protruding away from the electrode post. A portion of the first protrusion is fitted into the second protrusion. This improves the deformability of the portion of the terminal opposite to the first protrusion, facilitating the first protrusion to press the terminal to form the second protrusion, increasing the area of ​​the mating surface between the electrode post and the terminal, thereby increasing the mating area and mating force between the electrode post and the terminal. This improves the current-carrying capacity between the electrode post and the terminal.

[0007] In some embodiments, the distance between the bottom of the second groove and the first surface is H1, the distance between the surface of the second protrusion away from the electrode post and the first surface is H2, and the depth of the first protrusion fitting into the terminal is H3, satisfying: H1 < H3 ≤ H2. This helps ensure that the first protrusion presses a portion of the terminal material towards the periphery, thereby improving the reliability of the connection between the electrode post and the terminal, and avoiding unnecessary cost increases due to excessive bonding force in the molded conductive parts.

[0008] In some embodiments, the second protrusion extends in a ring shape around the axis of the electrode post. This allows for a larger contact area between the electrode post and the terminal, and also improves the structural symmetry of the conductive component, thereby improving the stress state of the conductive component.

[0009] In some embodiments, the portion of the first protrusion that fits into the second protrusion extends in a ring shape around the axis of the electrode post. This allows for a larger contact area between the electrode post and the terminal, and also improves the structural symmetry of the conductive component, thereby improving the stress state of the conductive component.

[0010] In some embodiments, the distance between the bottom of the second groove and the first surface is H1, satisfying: 0.3mm ≤ H1 ≤ 2.5mm. This ensures, on the one hand, the structural dimensions of the terminal are maintained, giving the terminal appropriate structural strength; on the other hand, it prevents the distance from being too large, which would result in excessive thickness of the terminal between the first groove and the first surface, thus facilitating the first protrusion to press the terminal to form the second protrusion.

[0011] In some embodiments, the first groove is an annular groove extending around the axis of the electrode post, and the bottom of the first groove is inclined along a first direction, forming an acute angle θ1 between the first direction and the radial direction of the electrode post. This causes the first protrusion to press against the terminal along the first direction, thereby improving the material flowability of the first protrusion and allowing the material to flow further, thus increasing the bonding depth between the first protrusion and the terminal. This creates a larger bonding surface between the electrode post and the terminal, resulting in a more reliable interlocking structure between them.

[0012] In some embodiments, the acute angle θ1 is 15° to 75°. This serves two purposes: firstly, it avoids the material flow of the first protrusion being too difficult due to an excessively small acute angle θ1, thus ensuring the material of the first protrusion has a suitable flow angle to improve the formability of the connection between the first protrusion and the terminal; secondly, it avoids the terminal and the pole having too small a stopping area in the axial direction of the pole due to an excessively large acute angle θ1, thus ensuring sufficient stopping area between the pole and the terminal in the axial direction of the pole to improve the reliability of the connection between the pole and the terminal.

[0013] In some embodiments, the radius of the electrode post is R1, and the inner diameter of the groove opening of the first groove is R2, satisfying: 25%R1≤R2≤85%R1. This allows the electrode post to have a suitable material size for material flow into the terminal to form the first protrusion, while avoiding excessively large dimensions of the first protrusion that would reduce material flowability. This improves the reliability and formability of the connection between the electrode post and the terminal.

[0014] In some embodiments, the conductive element further includes a current collector, one surface of which is provided with a third groove. The electrode post also includes a third protrusion disposed at the other end of the post along the axial direction, the third protrusion being fitted into the third groove; wherein the outer surface of the third protrusion engages with the inner wall of the third groove. This creates an engaging structure between the third protrusion and the inner wall of the third groove, effectively reducing the gap between the electrode post and the current collector and eliminating assembly gaps. This reduces the resistance of the connection interface between the electrode post and the current collector, thereby improving the current-carrying capacity between the electrode post and the terminal.

[0015] In some embodiments, a fourth protrusion is formed on the surface of the current collector away from the electrode post, protruding in a direction away from the electrode post, and a portion of the third protrusion is fitted into the fourth protrusion. This increases the contact area and contact force between the electrode post and the current collector, thereby improving the current flow capacity between them.

[0016] In some embodiments, the thickness of the current collector is H4, the distance between the surface of the fourth protrusion away from the electrode post and the surface of the current collector facing the electrode post is H5, and the depth of the third protrusion embedded in the current collector is H6, satisfying: H4 < H6 ≤ H5. This increases the contact area between the electrode post and the current collector, improving the reliability of the connection between them, and prevents the third protrusion from protruding from the fourth protrusion, thus avoiding excessive bonding force in the formed conductive parts and unnecessary cost increases.

[0017] In some embodiments, the fourth protrusion extends in a ring shape around the axis of the electrode post. This allows for a larger contact area between the electrode post and the current collector, while also improving the structural symmetry of the conductive component, thereby enhancing the stress state of the conductive component.

[0018] In some embodiments, the portion of the third protrusion that fits into the fourth protrusion extends in a ring shape around the axis of the electrode post. This allows for a larger contact area between the electrode post and the current collector, and also improves the structural symmetry of the conductive component, thereby improving the stress state of the conductive component.

[0019] In some embodiments, the third groove is an annular groove extending around the axis of the pole post, with the bottom of the third groove inclined along the second direction, forming an acute angle θ2 between the second direction and the radial direction of the pole post. This causes the third convex portion to press against the collector plate along the second direction, thereby improving the material flowability of the third convex portion and allowing the material to flow further, thus increasing the bonding depth between the third convex portion and the collector plate. This creates a larger bonding surface between the pole post and the collector plate, resulting in a more reliable interlocking structure between them.

[0020] In some embodiments, the acute angle θ2 is 15° to 75°. This serves two purposes: firstly, it avoids excessive difficulty in material flow in the third convex portion due to an excessively small acute angle θ2, thus ensuring the material in the third convex portion has a suitable flow angle, which improves the formability of the connection between the third convex portion and the collector plate; secondly, it avoids excessively large acute angle θ2, which would result in an insufficient area for the stop-fit ​​between the collector plate and the pole post in the axial direction of the pole post, thus ensuring sufficient area for the stop-fit ​​between the pole post and the collector plate in the axial direction of the pole post, which improves the reliability of the connection between the pole post and the collector plate.

[0021] In some embodiments, the radius of the pole is R1, and the inner diameter of the groove of the third groove is R3, satisfying: 25%R1≤R3≤85%R1. This allows the pole to have a suitable material size to flow into the manifold to form the third protrusion, while avoiding excessively large dimensions of the formed third protrusion that would reduce material flowability. This improves the reliability and formability of the connection between the pole and the manifold.

[0022] In some embodiments, the thickness of the current collector is H4, satisfying: 0.5mm≤H4≤2.5mm; thus, on the one hand, the current collector has suitable structural strength for connection with the tabs and terminals, and on the other hand, it avoids the reduction of the cell's energy density due to excessive thickness of the current collector.

[0023] And / or, the outer diameter of the third groove opening is smaller than the outer diameter of the third groove bottom. In this way, the pole post can be stopped and engaged with the collector plate axially through the third protrusion, thereby improving the reliability of the connection between the pole post and the collector plate.

[0024] In some embodiments, the height dimension of the electrode post is H, which satisfies: 3mm≤H≤30mm; in this way, it can avoid the difficulty of riveting the electrode post to the corresponding component due to the height dimension H being too small, and it can also avoid the space occupied by the electrode post being too large, which would affect the energy density of the battery cell.

[0025] And / or, the outer diameter of the first groove opening is smaller than the outer diameter of the first groove bottom. This allows the electrode post to engage with the terminal axially via the first protrusion, thereby improving the reliability of the connection between the electrode post and the terminal.

[0026] Secondly, embodiments of this application provide a cover plate assembly, which includes a cover plate, an upper plastic part, a lower plastic part, a sealing ring, and the aforementioned conductive element; a terminal is disposed on the cover plate, and a terminal is located on one side of the cover plate; the upper plastic part is sleeved on the terminal and located between the terminal and the cover plate; the lower plastic part is sleeved on the terminal and located on the side of the cover plate opposite to the terminal; the sealing ring is annularly disposed between the terminal and the cover plate. In this way, a mutually interlocking structure can be formed between the inner walls of the first protrusion and the first groove, effectively reducing the gap between the terminal and the electrode and eliminating assembly gaps. This reduces the resistance of the connection interface between the terminal and the electrode, thereby improving the current-carrying capacity between the terminal and the electrode, and thus improving the current-carrying capacity of the cover plate assembly.

[0027] Thirdly, embodiments of this application provide a battery cell including a housing, an electrode assembly, and the aforementioned cover assembly; the cover assembly closes to the housing to define a receiving cavity; the electrode assembly is disposed within the receiving cavity and connected to a terminal post. This allows for a mutually interlocking structure to be formed between the inner walls of the first protrusion and the first groove, effectively reducing the gap between the terminal post and the terminal and eliminating assembly gaps. Consequently, the resistance of the connection interface between the terminal post and the terminal can be reduced, thereby improving the current-carrying capacity between the terminal post and the terminal, and thus enhancing the current-carrying capacity of the battery cell.

[0028] The beneficial effects of the embodiments of this application are as follows:

[0029] In the embodiments of this application, by fitting the first protrusion into the first groove, and making the outer surface of the first protrusion interlock with the inner wall of the first groove, an interlocking structure can be formed between the first protrusion and the inner wall of the first groove, thereby effectively reducing the gap between the electrode and the terminal and eliminating assembly gaps. This reduces the resistance of the connection interface between the electrode and the terminal, thereby improving the current-carrying capacity between the electrode and the terminal. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the battery cell structure provided in an embodiment of this application;

[0032] Figure 2This is a schematic diagram of the structure of the cover plate assembly provided in an embodiment of this application;

[0033] Figure 3 This is a schematic diagram of the structure of the conductive element provided in an embodiment of this application;

[0034] Figure 4 It is along Figure 3 Sectional view of AA;

[0035] Figure 5 yes Figure 4 Enlarged schematic diagram of part B in the middle;

[0036] Figure 6 This is a schematic diagram of the conductive element provided in an embodiment of this application from another viewpoint.

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

[0038] Explanation of reference numerals in the attached figures:

[0039] 1000-cell;

[0040] 100 - Cover plate assembly;

[0041] 10 - Conductive components;

[0042] 11-pole; 111-first convex part; 112-third convex part; 113-cylinder

[0043] 12-Terminal; 121-First groove; 122-Second groove; 123-First surface; 124-Second protrusion;

[0044] 13-Collector's plate; 131-Third groove; 132-Fourth protrusion;

[0045] 20 - Cover plate; 30 - Upper plastic part; 40 - Lower plastic part; 50 - Sealing ring;

[0046] 200 - Electrode assembly; 201 - Positive electrode tab; 202 - Negative electrode tab;

[0047] 300 - Housing; 301 - Receiving cavity. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] Furthermore, it should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of this application. In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0050] The terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a product that comprises a list of elements includes not only those elements but also other elements not expressly listed or inherent to such a product.

[0051] The following combination Figures 1 to 6 The conductive element 10, cover plate assembly 100 and battery cell 1000 provided in the embodiments of this application will be described in detail.

[0052] Please see Figure 1 This application provides a battery cell 1000. The battery cell 1000 includes a housing 300, an electrode assembly 200, and the aforementioned cover plate assembly 100. The cover plate 20 closes to the housing 300 to define a receiving cavity 301. The electrode assembly 200 is disposed within the receiving cavity 301 and is connected to the electrode post 11.

[0053] It is understood that the tabs of the electrode assembly 200 are connected to the pole post 11 through the current collector 13.

[0054] Among them, the 1000 cell can also be called a battery cell or a single cell battery.

[0055] It is understood that the battery cell 1000 can be a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., and this application embodiment is not limited in this regard. The external structure of the battery cell 1000 can be cylindrical, flat, cuboid, or other shapes, etc., and this application embodiment is not limited in this regard either.

[0056] For example, this embodiment provides a lithium-ion secondary battery, specifically in a cylindrical shape.

[0057] It is understandable that an electrolyte is provided in the receiving cavity 301.

[0058] The electrode assembly 200 includes a positive electrode, a negative electrode, and a separator. The battery cell 1000 primarily stores or transmits electrical energy by the movement of metal ions between the positive and negative electrode sheets. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on a portion of the surface of the positive current collector, while the uncoated positive current collector serves as the positive electrode tab 201. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on a portion of the surface of the negative current collector, while the uncoated negative current collector serves as the negative electrode tab 202. The material of the negative current collector can be copper, and the negative active material can be carbon or silicon, etc. Specifically, there are multiple positive electrode tabs 201 stacked together, and multiple negative electrode tabs 202 stacked together. Correspondingly, the positive electrode tabs 201 are connected to the terminal post 11 through the positive current collector 13, and the negative electrode tabs 202 are connected to the housing 300 through the negative current collector 13, so that the battery cell 1000 serves as the positive and negative output terminals through the terminal post 11 and the housing 300, respectively.

[0059] Please see Figure 2 In some embodiments, the cover plate assembly 100 includes a cover plate 20, an upper plastic component 30, a lower plastic component 40, a sealing ring 50, and the aforementioned conductive component 10. A terminal 11 passes through the cover plate 20. A terminal 12 is located on one side of the cover plate 20. The upper plastic component 30 is sleeved on the terminal 11 and located between the terminal 12 and the cover plate 20. The lower plastic component 40 is sleeved on the terminal 11 and located on the side of the cover plate 20 opposite to the terminal 12. The sealing ring 50 is annularly disposed between the terminal 11 and the cover plate 20.

[0060] It is understood that the lower plastic part 40 and the upper plastic part 30 can be bonded to the cover plate 20. The pole post 11 is supported on the lower plastic part 40, the upper plastic part 30 and the cover plate 20 through the terminal 12 and the current collector 13.

[0061] Please see Figures 3 to 5 In some embodiments, the conductive element 10 includes a terminal 12 and a post 11. The terminal 12 has a first surface 123. The first surface 123 is provided with a first groove 121. The post 11 includes a column 113 and a first protrusion 111 disposed at one axial end of the column 113. The first protrusion 111 is fitted into the first groove 121. The outer surface of the first protrusion 111 engages with the inner wall of the first groove 121.

[0062] It is understandable that terminal 12 is block-shaped and has no through holes.

[0063] The radius of the post 113 is 1 / 10 to 3 / 4 of the radius of the cell 1000. This avoids material waste due to excessively large post 11 size, and also avoids insufficient current requirements due to excessively small post 11 size.

[0064] It is understood that the surface of terminal 12 facing away from the first groove 121 is used for connection with the connecting bar.

[0065] It is understood that through cold heading, stamping, riveting, or other metal component joining processes, one end of the pole post 11 can flow into the terminal 12 under the action of force, thereby squeezing the terminal 12 and extruding a first groove 121 on the terminal 12, and forming a first protrusion 111 embedded in the first groove 121 at one end of the pole post 11. The outer surface of the first protrusion 111 and the inner wall of the first groove 121 interlock to form a self-riveting structure. The interface where the outer surface of the first protrusion 111 and the inner wall of the first groove 121 interlock is the mating surface between the pole post 11 and the terminal 12.

[0066] It is understandable that one end of the electrode post 11 flows into the terminal 12 under the action of force, causing the deformation of the electrode post 11 and the terminal 12 to be plastic deformation. During this plastic deformation process, the microstructure of the contact surface between the electrode post 11 and the terminal 12 is an interlocking concave-convex structure, and the electrode post 11 and the terminal 12 will squeeze and interlock with each other. In this way, not only is the actual contact area between the electrode post 11 and the terminal 12 larger, but the bonding force between the electrode post 11 and the terminal 12 can also be increased, which helps to suppress the relative movement between the electrode post 11 and the terminal 12.

[0067] For example, the column 113 is integrally formed with the first protrusion 111.

[0068] In this embodiment, by fitting the first protrusion 111 into the first groove 121, and making the outer surface of the first protrusion 111 engage with the inner wall of the first groove 121, a mutually engaging structure is formed between the first protrusion 111 and the inner wall of the first groove 121. This effectively reduces the gap between the electrode post 11 and the terminal 12, eliminating assembly gaps. Consequently, the resistance of the connection interface between the electrode post 11 and the terminal 12 is reduced, thereby improving the current-carrying capacity between the electrode post 11 and the terminal 12.

[0069] Please see Figures 3 to 5 In some embodiments, a second groove 122 is provided on the side of the terminal 12 opposite to the first groove 121. The bottom of the second groove 122 is formed with a second protrusion 124 protruding in a direction away from the pole post 11. A portion of the first protrusion 111 is fitted into the second protrusion 124.

[0070] It is understood that when the conductive component 10 is formed, the first protrusion 111 pushes against the bottom of the first groove 121 to form a second protrusion 124 protruding away from the pole post 11 at the bottom of the second groove 122.

[0071] It is understood that at least part of the first protrusion 111 is disposed opposite to the second groove 122 along the axial direction of the pole post 11.

[0072] For example, the first protrusion 111 is disposed opposite to the second groove 122 along the axial direction of the pole post 11.

[0073] In this embodiment, by providing the second protrusion 124, the deformability of the portion of terminal 12 opposite to the first protrusion 111 can be improved. This facilitates the first protrusion 111 pressing the terminal 12 to form the second protrusion 124, increasing the area of ​​the mating surface between the electrode post 11 and the terminal 12, thereby increasing the mating area and mating force between the electrode post 11 and the terminal 12. This improves the current-carrying capacity between the electrode post 11 and the terminal 12.

[0074] Please see Figure 5 In some embodiments, the distance between the bottom of the second groove 122 and the first surface 123 is H1, the distance between the surface of the second protrusion 124 away from the pole post 11 and the first surface 123 is H2, and the depth of the first protrusion 111 fitted into the terminal 12 is H3, satisfying: H1<H3≤H2.

[0075] It is understood that the height dimension H3 of the first protrusion 111 fitting into the terminal 12 is greater than the distance H1 between the bottom of the second groove 122 and the first surface 123. This allows the first protrusion 111 to extend beyond the bottom of the second groove 122, which helps to reduce the thickness of the portion of the terminal 12 covering the first protrusion 111. This improves the flowability of the first protrusion 111 to the periphery, ensuring that the first protrusion 111 squeezes part of the material of the terminal 12 to the periphery, thereby improving the reliability of the connection between the pole post 11 and the terminal 12.

[0076] It is understood that the height dimension H3 of the first protrusion 111 fitting into the terminal 12 is not greater than the distance H2 between the surface of the second protrusion 124 away from the pole post 11 and the first surface 123. This can prevent the first protrusion 111 from protruding from the second protrusion 124, so as to avoid excessive bonding force of the molded conductive part 10, which would lead to unnecessary cost increases.

[0077] Please see Figure 3 In some embodiments, the second protrusion 124 extends in a ring around the axis of the pole post 11. This allows for a larger contact area between the pole post 11 and the terminal 12, and also improves the structural symmetry of the conductive element 10, thereby improving the stress state of the conductive element 10.

[0078] Please see Figure 4 and Figure 5 In some embodiments, the portion of the first protrusion 111 that fits into the second protrusion 124 extends in a ring around the axis of the pole post 11. This allows for a larger contact area between the pole post 11 and the terminal 12, and also improves the structural symmetry of the conductive element 10, thereby improving the stress state of the conductive element 10.

[0079] Please see Figure 5 In some embodiments, the distance between the bottom of the second groove 122 and the first surface 123 is H1, which satisfies: 0.3mm≤H1≤2.5mm.

[0080] It is understood that the distance H1 between the bottom of the second groove 122 and the first surface 123 is, but is not limited to, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, and 2.5mm.

[0081] In this embodiment, by limiting the distance H1 between the bottom of the second groove 122 and the first surface 123, on the one hand, the structural dimensions of the terminal 12 can be guaranteed so that the terminal 12 has appropriate structural strength; on the other hand, the excessive distance can be avoided so that the thickness of the terminal 12 between the first groove 121 and the first surface 123 is too large, thereby facilitating the first protrusion 111 to press the terminal 12 to form the second protrusion 124.

[0082] Please see Figure 4 and Figure 5 In some embodiments, the first groove 121 is an annular groove extending around the axis of the pole post 11. The bottom of the first groove 121 is inclined along a first direction. An acute angle θ1 is formed between the first direction and the radial direction of the pole post 11. This causes the first protrusion 111 to press against the terminal 12 along the first direction, thereby improving the material flowability of the first protrusion 111 and allowing the material to flow further, thus increasing the bonding depth between the first protrusion 111 and the terminal 12. This results in a larger bonding surface between the pole post 11 and the terminal 12, making the engagement structure between the pole post 11 and the terminal 12 more reliable.

[0083] Please see Figure 5 In some embodiments, the acute angle θ1 is 15° to 75°.

[0084] It is understood that the acute angle θ1 includes, but is not limited to, 15°, 17°, 19°, 21°, 23°, 25°, 27°, 29°, 31°, 33°, 35°, 37°, 39°, 41°, 43°, 45°, 47°, 49°, 51°, 53°, 55°, 57°, 59°, 61°, 63°, 65°, 67°, 69°, 71°, 73°, and 75°.

[0085] In this embodiment, the above-mentioned limitations can, on the one hand, prevent the acute angle θ1 from being too small, which would make the material flow of the first protrusion 111 too difficult, thereby ensuring that the material of the first protrusion 111 has a suitable flow angle, which is conducive to improving the formability of the first protrusion 111 and the terminal 12; on the other hand, can prevent the acute angle θ1 from being too large, which would, in turn, make the area of ​​the stop fit between the terminal 12 and the pole post 11 in the axial direction of the pole post 11 too small, thereby ensuring that the pole post 11 and the terminal 12 have sufficient area for stop fit in the axial direction of the pole post 11, which is conducive to improving the reliability of the connection between the pole post 11 and the terminal 12.

[0086] The maximum radius of the second protrusion 124 is R01, and the inner diameter of the groove of the first groove 121 is R2. Correspondingly, H2 = (R01 - R2) * tanθ1.

[0087] Please see Figure 5 In some embodiments, the radius of the pole post 11 is R1, and the inner diameter of the groove opening of the first groove 121 is R2, satisfying: 25%R1≤R2≤85%R1. This allows the pole post 11 to have a suitable material size for material flow into the terminal 12 to form the first protrusion 111, while avoiding excessively large sizes of the first protrusion 111 that would reduce material flowability. This improves the reliability and formability of the connection between the pole post 11 and the terminal 12.

[0088] It is understood that the inner diameter R2 of the groove of the first groove 121 includes, but is not limited to, 25%R1, 27%R1, 29%R1, 31%R1, 33%R1, 35%R1, 37%R1, 39%R1, 41%R1, 43%R1, 45%R1, 47%R1, 49%R1, 51%R1, 53%R1, 55%R1, 57%R1, 59%R1, 61%R1, 63%R1, 65%R1, 67%R1, 69%R1, 71%R1, 73%R1, 75%R1, 77%R1, 79%R1, 81%R1, 83%R1, and 85%R1.

[0089] It is understood that before riveting the electrode post 11 to the terminal 12, a groove can be provided on the end face of the electrode post 11 facing the terminal 12, and the groove is opposite to the part of the terminal 12 surrounded by the first groove 121. In this way, when the electrode post 11 and the terminal 12 are pressed together, the flowability of the material around the groove of the electrode post 11 can be improved, and the flow of the material around the groove of the electrode post 11 can be guided by the setting of the groove.

[0090] Please see Figures 3 to 5 In some embodiments, the conductive element 10 further includes a current collector 13. A third groove 131 is provided on one surface of the current collector 13. The pole post 11 also includes a third protrusion 112 provided at the other end of the pole post 113 along its axial direction. The third protrusion 112 is fitted into the third groove 131. The outer surface of the third protrusion 112 engages with the inner wall of the third groove 131.

[0091] It is understandable that the surface of the collector plate 13 facing away from the pole post 11 is used to connect with the pole tab.

[0092] It is understood that through cold heading, stamping, riveting, or other metal component joining processes, one end of the pole post 11 can flow into the collector plate 13 under the action of force, thereby squeezing the collector plate 13 and extruding the first groove 121 on the collector plate 13, and forming a third protrusion 112 at one end of the pole post 11 that is embedded in the third groove 131. The outer surface of the third protrusion 112 and the inner wall of the third groove 131 interlock to form a self-riveting structure. The interface where the outer surface of the third protrusion 112 and the inner wall of the third groove 131 interlock is the mating surface between the pole post 11 and the collector plate 13.

[0093] It is understandable that one end of the pole post 11 flows into the collector disk 13 under the action of force, causing the deformation of the pole post 11 and the collector disk 13 to be plastic deformation. During this plastic deformation process, the microstructure of the contact surface between the pole post 11 and the collector disk 13 is an interlocking concave-convex structure, and the pole post 11 and the collector disk 13 will squeeze and interlock with each other. In this way, not only is the actual contact area between the pole post 11 and the collector disk 13 larger, but the bonding force between the pole post 11 and the collector disk 13 can also be increased, which helps to suppress the relative movement between the pole post 11 and the collector disk 13.

[0094] For example, the column 113 is integrally formed with the third protrusion 112.

[0095] In this embodiment, by fitting the third protrusion 112 into the third groove 131, and making the outer surface of the third protrusion 112 interlock with the inner wall of the third groove 131, an interlocking structure is formed between the third protrusion 112 and the inner wall of the third groove 131, thereby effectively reducing the gap between the electrode post 11 and the current collector 13 and eliminating the assembly gap. This reduces the resistance of the connection interface between the electrode post 11 and the current collector 13, thereby improving the current-carrying capacity between the electrode post 11 and the terminal 12.

[0096] Please see Figures 4 to 6 In some embodiments, the third protrusion 112 pushes against the bottom of the third groove 131 to form a fourth protrusion 132 protruding away from the pole post 11 on the surface of the collector plate 13 facing away from the pole post 11. Part of the third protrusion 112 is fitted into the fourth protrusion 132. In this way, the contact area and contact force between the pole post 11 and the collector plate 13 can be increased, thereby improving the current flow capacity between the pole post 11 and the collector plate 13.

[0097] It is understood that when the conductive component 10 is formed, the third protrusion 112 pushes against the bottom of the third groove 131 to form a fourth protrusion 132 on the surface of the current collector 13 away from the pole post 11, which protrudes in a direction away from the pole post 11.

[0098] Please see Figures 4 to 5 In some embodiments, the thickness of the collector plate 13 is H4, the distance between the surface of the fourth protrusion 132 away from the pole post 11 and the surface of the collector plate 13 facing the pole post 11 is H5, and the depth of the third protrusion 112 embedded in the collector plate 13 is H6, satisfying: H4<H6≤H5.

[0099] It is understandable that the height dimension H6 of the third protrusion 112 fitting into the collector plate 13 is greater than the thickness H4 of the collector plate 13, which allows the third protrusion 112 to extend beyond the original surface of the collector plate 13, thereby increasing the bonding area between the pole post 11 and the collector plate 13, and thus improving the reliability of the bonding between the pole post 11 and the collector plate 13.

[0100] It is understood that the height dimension H6 of the third protrusion 112 fitting into the collector plate 13 is not greater than the distance H5 between the surface of the fourth protrusion 132 away from the pole post 11 and the surface of the collector plate 13 facing the pole post 11. This can prevent the third protrusion 112 from protruding from the fourth protrusion 132, so as to avoid excessive bonding force of the molded conductive part 10, which would lead to unnecessary cost increases.

[0101] Please see Figure 6In some embodiments, the fourth protrusion 132 extends in a ring around the axis of the pole post 11. This allows for a larger contact area between the pole post 11 and the current collector 13, and also improves the structural symmetry of the conductive element 10, thereby improving the stress state of the conductive element 10.

[0102] Please see Figures 4 to 5 In some embodiments, the portion of the third protrusion 112 that fits into the fourth protrusion 132 extends in a ring around the axis of the pole post 11. This allows for a larger contact area between the pole post 11 and the current collector 13, and also improves the structural symmetry of the conductive element 10, thereby improving the stress state of the conductive element 10.

[0103] Please see Figures 4 to 5 In some embodiments, the third groove 131 is an annular groove extending around the axis of the pole post 11. The bottom of the third groove 131 is inclined along the second direction. The second direction forms an acute angle θ2 with the radial direction of the pole post 11. This causes the third protrusion 112 to press against the collector plate 13 along the second direction, thereby improving the material flowability of the third protrusion 112 and allowing the material of the third protrusion 112 to flow further, thus increasing the bonding depth between the third protrusion 112 and the collector plate 13. In this way, a larger bonding surface can be formed between the pole post 11 and the collector plate 13, making the interlocking structure between the pole post 11 and the collector plate 13 reliable.

[0104] It can be understood that, considering the aforementioned acute angle θ1, the longitudinal section of pole column 11 is X-shaped, as shown below. Figure 4 As shown.

[0105] Among them, the maximum radius of the fourth protrusion 132 is R01, the inner diameter of the groove of the third groove 131 is R3, and correspondingly, H2=(R01-R3)*tanθ2.

[0106] Please see Figures 4 to 5 In some embodiments, the acute angle θ2 is 15° to 75°.

[0107] It is understood that the acute angle θ2 includes, but is not limited to, 15°, 17°, 19°, 21°, 23°, 25°, 27°, 29°, 31°, 33°, 35°, 37°, 39°, 41°, 43°, 45°, 47°, 49°, 51°, 53°, 55°, 57°, 59°, 61°, 63°, 65°, 67°, 69°, 71°, 73°, and 75°.

[0108] In this embodiment, the above-mentioned limitations can, on the one hand, prevent the acute angle θ2 from being too small, which would make the material flow of the third protrusion 112 too difficult, thereby ensuring that the material of the third protrusion 112 has a suitable flow angle, which is conducive to improving the formability of the combination of the third protrusion 112 and the collector plate 13; on the other hand, can prevent the acute angle θ2 from being too large, which would, in turn, make the area of ​​the stop fit between the collector plate 13 and the pole post 11 in the axial direction of the pole post 11 too small, thereby ensuring that the pole post 11 and the collector plate 13 have sufficient area for stop fit in the axial direction of the pole post 11, which is conducive to improving the reliability of the combination of the pole post 11 and the collector plate 13.

[0109] Please see Figures 4 to 5 In some embodiments, the radius of the pole post 11 is R1, and the inner diameter of the groove opening of the third groove 131 is R3, satisfying: 25%R1≤R3≤85%R1. This allows the pole post 11 to have suitable material dimensions for flowing into the collector plate 13 to form the third protrusion 112, while avoiding excessively large dimensions of the formed third protrusion 112 that would reduce material flowability. This improves the reliability and ease of forming of the connection between the pole post 11 and the collector plate 13.

[0110] It is understood that the inner diameter R3 of the groove of the third groove 131 includes, but is not limited to, 25%R1, 27%R1, 29%R1, 31%R1, 33%R1, 35%R1, 37%R1, 39%R1, 41%R1, 43%R1, 45%R1, 47%R1, 49%R1, 51%R1, 53%R1, 55%R1, 57%R1, 59%R1, 61%R1, 63%R1, 65%R1, 67%R1, 69%R1, 71%R1, 73%R1, 75%R1, 77%R1, 79%R1, 81%R1, 83%R1, and 85%R1.

[0111] It is understandable that before riveting the pole post 11 to the collector plate 13, a groove can be provided on the end face of the pole post 11 facing the collector plate 13, and the groove is opposite to the part of the collector plate 13 surrounded by the third groove 131. In this way, when the pole post 11 and the collector plate 13 are pressed together, the flowability of the material around the groove of the pole post 11 can be improved, and the flow of the material around the groove of the pole post 11 can be guided by the setting of the groove.

[0112] Please see Figure 4 In some embodiments, the thickness of the collector plate 13 is H4, satisfying: 0.5mm≤H4≤2.5mm.

[0113] It is understood that the thickness H4 of the manifold 13 includes, but is not limited to, 0.5mm, 0.57mm, 0.6mm, 0.64mm, 0.7mm, 0.71mm, 0.78mm, 0.8mm, 0.85mm, 0.9mm, 0.92mm, 0.99mm, 1.0mm, 1.06mm, 1.1mm, 1.13mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, and 2.5mm.

[0114] In this embodiment, by limiting the thickness H4 of the current collector 13, on the one hand, the current collector 13 can have suitable structural strength to connect with the tabs and the pole post 11, and on the other hand, the excessive thickness of the current collector 13 can be avoided, which would reduce the energy density of the cell 1000.

[0115] Please see Figure 4 In some embodiments, the outer diameter of the opening of the third groove 131 is smaller than the outer diameter of the bottom of the third groove 131. In this way, the pole post 11 can be stopped and engaged with the collector plate 13 in the axial direction of the pole post 11 through the third protrusion 112, thereby improving the reliability of the connection between the pole post 11 and the collector plate 13.

[0116] In some embodiments, the height dimension H of the terminal post 11 satisfies: 3mm≤H≤30mm. This avoids the difficulty of riveting the terminal post 11 to the corresponding component if the height dimension H is too small, and also avoids the terminal post 11 height dimension A being too large, which would occupy too much space and affect the energy density of the cell 1000.

[0117] It is understood that the height dimension H of the pole post 11 includes, but is not limited to, 3mm, 3.5mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 19.5mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, and 30mm.

[0118] In some embodiments, the outer diameter of the opening of the first groove 121 is smaller than the outer diameter of the bottom of the first groove 121. In this way, the pole post 11 can be stopped and engaged with the terminal 12 in the axial direction of the pole post 11 through the first protrusion 111, thereby improving the reliability of the connection between the pole post 11 and the terminal 12.

[0119] In this embodiment, during the assembly of the battery cell 1000, the electrode post 11 is first connected to the current collector 13. Then, the positive electrode tab 201 of the electrode assembly 200 is welded to the current collector 13. Next, the electrode post 11 is sequentially passed through the sealing ring 50, the lower plastic part 40, the cover plate 20, and the upper plastic part 30, and then the electrode post 11 is connected to the terminal 12. Next, the electrode assembly 200 is installed into the housing 300, and the cover plate 20 is welded to the housing 300. Finally, the negative electrode tab 202 is welded to the bottom of the housing 300.

[0120] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A conductive element (10), characterized in that, include: Terminal (12), the terminal (12) having a first surface (123), the first surface (123) being provided with a first groove (121); as well as The pole post (11) includes a column (113) and a first protrusion (111) disposed at one axial end of the column (113), the first protrusion (111) being fitted into the first groove (121); The outer surface of the first protrusion (111) engages with the inner wall of the first groove (121).

2. The conductive element (10) according to claim 1, characterized in that, The terminal (12) has a second groove (122) on the side away from the first groove (121), and the bottom of the second groove (122) has a second protrusion (124) protruding in a direction away from the pole post (11); part of the first protrusion (111) is fitted into the second protrusion (124).

3. The conductive element (10) according to claim 2, characterized in that, The distance between the bottom of the second groove (122) and the first surface (123) is H1, the distance between the surface of the second protrusion (124) away from the pole post (11) and the first surface (123) is H2, and the depth of the first protrusion (111) fitted into the terminal (12) is H3, satisfying: H1<H3≤H2.

4. The conductive element (10) according to claim 2, characterized in that, The second protrusion (124) extends in a ring around the axis of the pole post (11).

5. The conductive element (10) according to claim 4, characterized in that, The portion of the first protrusion (111) that fits into the second protrusion (124) extends in a ring around the axis of the pole post (11).

6. The conductive element (10) according to any one of claims 2-5, characterized in that, The distance between the bottom of the second groove (122) and the first surface (123) is H1, which satisfies: 0.3mm≤H1≤2.5mm.

7. The conductive element (10) according to any one of claims 1-5, characterized in that, The first groove (121) is an annular groove extending around the axis of the pole post (11). The bottom of the first groove (121) is inclined along a first direction, and the first direction forms an acute angle θ1 with the radial direction of the pole post (11).

8. The conductive element (10) according to claim 7, characterized in that, The acute angle θ1 is 15° to 75°.

9. The conductive element (10) according to claim 7, characterized in that, The radius of the pole post (11) is R1, and the inner diameter of the groove opening of the first groove (121) is R2, satisfying: 25%R1≤R2≤85%R1.

10. The conductive element (10) according to any one of claims 1-5, characterized in that, The conductive component (10) further includes a current collector (13), one surface of which is provided with a third groove (131). The pole post (11) further includes a third protrusion (112) disposed at the other end of the axial direction of the pole body (113), the third protrusion (112) being fitted into the third groove (131); wherein, the outer surface of the third protrusion (112) and the inner wall of the third groove (131) engage with each other.

11. The conductive element (10) according to claim 10, characterized in that, The collector plate (13) has a fourth protrusion (132) on its surface away from the pole post (11), which protrudes in a direction away from the pole post (11); a portion of the third protrusion (112) is fitted into the fourth protrusion (132).

12. The conductive element (10) according to claim 11, characterized in that, The thickness of the collector plate (13) is H4, the distance between the surface of the fourth protrusion (132) away from the pole post (11) and the surface of the collector plate (13) facing the pole post (11) is H5, and the depth of the third protrusion (112) embedded in the collector plate (13) is H6, satisfying: H4<H6≤H5.

13. The conductive element (10) according to claim 11, characterized in that, The fourth protrusion (132) extends in a ring around the axis of the pole post (11).

14. The conductive element (10) according to claim 13, characterized in that, The portion of the third protrusion (112) that fits into the fourth protrusion (132) extends in a ring around the axis of the pole post (11).

15. The conductive element (10) according to claim 10, characterized in that, The third groove (131) is an annular groove extending around the axis of the pole post (11). The bottom of the third groove (131) is inclined along the second direction, and the second direction forms an acute angle θ2 with the radial direction of the pole post (11).

16. The conductive element (10) according to claim 15, characterized in that, The acute angle θ2 is 15° to 75°.

17. The conductive element (10) according to claim 15, characterized in that, The radius of the pole post (11) is R1, and the inner diameter of the groove of the third groove (131) is R3, satisfying: 25%R1≤R3≤85%R1.

18. The conductive element (10) according to claim 10, characterized in that, The thickness of the collector plate (13) is H4, which satisfies: 0.5mm≤H4≤2.5mm; And / or, the outer diameter of the opening of the third groove (131) is smaller than the outer diameter of the bottom of the third groove (131).

19. The conductive element (10) according to any one of claims 1-5, characterized in that, The height dimension of the pole post (11) is H, which satisfies: 3mm≤H≤30mm; And / or, the outer diameter of the opening of the first groove (121) is smaller than the outer diameter of the bottom of the first groove (121).

20. A cover plate assembly (100), characterized in that, include: Cover plate (20); The conductive element (10) as described in any one of claims 1-19, wherein the pole post (11) passes through the cover plate (20), and the terminal (12) is located on one side of the cover plate (20); The upper plastic part (30) is sleeved on the pole post (11) and located between the terminal (12) and the cover plate (20); The lower plastic part (40) is fitted onto the pole post (11) and located on the side of the cover plate (20) opposite to the terminal (12); and A sealing ring (50) is arranged between the pole post (11) and the cover plate (20).

21. A battery cell (1000), characterized in that, include: Casing (300); The cover plate assembly (100) as claimed in claim 20, wherein the cover plate (20) closes to the housing (300) to define a receiving cavity (301); and An electrode assembly (200) is disposed within the receiving cavity (301), and the electrode assembly (200) is connected to the electrode post (11).

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