Pole, battery cell cover plate assembly and battery cell

Abstract

The invention relates to the technical field of batteries, and discloses a pole, a battery cell cover plate assembly and a battery cell. The pole comprises a pole body, the pole body is provided with a first conductive section and a pair of second conductive sections which are connected, and the pair of second conductive sections are located on the two opposite sides of the first conductive section in the Y direction; the two opposite sides of the upper end face of the first conductive section in the X direction are respectively provided with a bent flange, the pole has a pre-assembly state and an assembly state, and in the pre-assembly state, the bent flanges extend in the Z direction; in an assembling state, the pair of bent flanges are bent in the direction away from each other and extend in the X direction after being bent, the upper end faces of the first conductive section and the second conductive section in the Z direction are flush with the upper surfaces of the bent flanges in the Z direction, and on a projection plane perpendicular to the Z direction, the orthographic projection of the pole body is in a runway shape. During assembly, the second conductive section is not provided with a bent flange, so that the problems of material pulling and insufficient filler in the area can be avoided, and the overall flatness of the pole and the yield of the cover plate are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to an electrode post, a cell cover assembly, and a cell. Background Technology

[0002] The cover plate is a key component in the battery cell, serving multiple purposes such as welding it to the casing to form a sealed cavity, leading out the positive and negative electrodes, and acting as an assembly carrier. Currently, cover plate forming methods mainly include riveting, electrode welding, injection molding, and flanging. Among these, the flanged cover plate achieves a seal by folding the upper convex edge of the electrode post outwards to press against the upper plastic. Compared to the traditional riveted cover plate, this method eliminates the riveting block, making it simpler and more reliable.

[0003] Due to the limitation of the cover width, the terminals of blade cells are mostly designed as a racetrack shape of "two semicircles + a middle rectangle". However, there is a difference in the outward turning of the convex edge of the semicircular part and the rectangular part: the convex edge of the semicircular part is prone to insufficient filling when turning outward, which makes it impossible for the convex edge to fully adhere to the plastic after turning outward, thus affecting the yield of the cover. At the same time, the outward turning of the convex edge of the semicircular part will pull the material at its root during the process, resulting in poor flatness of the upper end surface of the terminal after turning outward. Summary of the Invention

[0004] This invention provides a terminal post, a cell cover plate assembly, and a cell to solve the problems that easily lead to a decrease in cell yield and poor flatness of the upper end face of the terminal post when using racetrack-shaped terminal posts to prepare flanged covers.

[0005] In a first aspect, the present invention provides an electrode post, comprising: The electrode body has a first conductive segment and a pair of second conductive segments connected together. Along the Y direction, the pair of second conductive segments are located on opposite sides of the first conductive segment. The upper end surface of the first conductive segment is provided with bent flanges on opposite sides in the X direction. The pole includes a pre-assembled state and an assembled state. In the pre-assembled state, the bent flange extends along the Z direction. In the assembled state, the pair of bent flanges bend away from each other and extend along the X direction after bending. Along the Z direction, the upper end faces of the first conductive segment and the second conductive segment are flush with the upper surface of the bent flange. On the projection plane perpendicular to the Z direction, the orthographic projection of the pole body is in the shape of a racetrack.

[0006] Beneficial effects: This invention designs the electrode body as a structure containing a first conductive segment and a pair of second conductive segments, and sets bent flanges on both sides of the first conductive segment in the X direction, which are pre-extended in the Z direction and bent away from each other during assembly and extended in the X direction. This ensures that the electrode post's orthographic projection is racetrack-shaped to fit the width limitation of the blade cell cover plate, and avoids the problem of insufficient filler when the convex edge of the semicircular part of the traditional racetrack-shaped electrode post is turned outward. This allows the bent flanges to fit the plastic completely, while reducing the pulling of the electrode post root material during the outward turning process. This effectively improves the yield rate of the cell cover plate and the cell, ensures the flatness of the upper surface of the electrode post, and retains the advantages of the traditional flanged cover plate in terms of simplicity and reliability.

[0007] In one alternative embodiment, in the pre-assembled state, the upper surfaces of the first conductive segment and the second conductive segment are flush in the Z direction.

[0008] Beneficial effects: In the pre-assembled state, the upper Z-direction surfaces of the first conductive segment and the second conductive segment are flush, providing a stable benchmark for precise bending and flanging during assembly. This ensures that the upper surfaces of the electrode post are flush after bending, further improving the flatness of the electrode post and the assembly accuracy of the cover plate, and guaranteeing the sealing effect and the yield rate of the battery cell.

[0009] In one optional embodiment, in the pre-assembled state, along the Z direction, the height of the bent flange is h1, the height of the second conductive segment is h2, and the relationship between h1 and h2 satisfies: 0.2≤h1 / h2≤0.4.

[0010] Beneficial effects: The present invention limits the ratio of the bending flange height h1 to the second conductive section height h2 to between 0.2 and 0.4, which can ensure that there is enough material for the bending flange to achieve reliable folding and sealing, and avoid the root of the pole being pulled when folding due to excessive height, thereby further ensuring the flatness of the pole and the yield of the cover plate.

[0011] In one optional embodiment, in the pre-assembled state, along the X direction, the width of the first conductive segment is n, and the width of the bent flange is m, wherein the relationship between n and m satisfies: 0.15≤m / n≤0.25.

[0012] Beneficial effects: The present invention limits the ratio of the width n of the first conductive section to the width m of the bending flange in the pre-assembled state to between 0.15 and 0.25, which can ensure that there is sufficient material for the bending flange to achieve a tight seal, while avoiding stress concentration caused by excessive width, thus ensuring the stability of the pole structure and the reliability of the cover plate assembly.

[0013] In one optional embodiment, the pole further includes a pole base plate located at the end of the pole body away from the bent flange, and on a projection plane perpendicular to the Z direction, the orthographic projection of the pole body falls within the orthographic projection range of the pole base plate; and / or, on a projection plane perpendicular to the Z direction, the orthographic projection shape of the first conductive segment is rectangular, and the orthographic projection shape of the second conductive segment is semi-circular.

[0014] Beneficial effects: By setting a base plate at the end of the electrode body away from the bent edge, and ensuring that the orthographic projection of the electrode body falls within the orthographic projection range of the base plate, the present invention can enhance the overall structural stability of the electrode, provide a solid support for electrode assembly, improve the fitting accuracy between the electrode and other components of the battery cell, and further ensure the sealing effect of the cover and the reliability of the battery cell.

[0015] In a second aspect, the present invention also provides a cell cover assembly, comprising: The cover body has a first surface and a second surface that are disposed opposite to each other along the Z direction, and the cover body has a first clearance hole that is disposed through the Z direction. A plastic part is located on the first surface, and the plastic part has a second clearance hole that is disposed through the Z direction and communicates with the first clearance hole; The aforementioned pole post has a portion of its body inserted into the first clearance hole and the second clearance hole. The second clearance hole has a pair of stepped portions protruding from its hole wall along the X direction. In the assembled state, the pair of stepped portions and the pair of bent flanges are arranged in a one-to-one correspondence. Along the Z direction, the lower surface of the bent flange abuts against the upper surface of the stepped portion.

[0016] Beneficial effects: The battery cell cover assembly of the present invention, by setting a plastic part with a stepped part, corresponds one-to-one with the bent flange in the assembly state of the terminal post, which not only achieves precise positioning and reliable sealing between the terminal post and the plastic part, but also avoids the problems of insufficient filler and material pulling during bending by means of the optimized structure of the terminal post, thereby improving the assembly accuracy, sealing reliability and overall yield of the cover assembly.

[0017] In one alternative embodiment, in the assembled state, the width of the stepped portion and the length of the bent flange in the X direction are equal, as are their lengths in the Y direction.

[0018] Beneficial effects: This invention makes the width and length of the bent flange in the assembled state equal to the width and length of the step, which can increase the contact area between the two, improve the fit and sealing performance and the uniformity of stress, avoid local stress concentration or sealing gaps, and further ensure the assembly stability of the cell cover assembly and the reliability of the cell.

[0019] In one optional embodiment, the pole post further includes a pole post base plate located at the end of the pole post body away from the bent flange, and the pole post base plate is spaced apart from the second surface.

[0020] Beneficial effects: The pole base plate and the second surface of the cover body of the present invention are arranged at intervals, which not only retains the structural stability and assembly support of the pole, but also avoids interference caused by direct contact between the base and the cover body, ensuring the assembly coordination of each component of the cover plate assembly, and further improving the sealing effect and assembly yield.

[0021] In one optional embodiment, the cell cover assembly further includes an insulating seal, the insulating seal comprising a first ring and a second ring connected along the Z direction, the first ring and the second ring being sleeved on the electrode body, the first ring being located inside the first clearance hole, and the second ring being located between the cover body and the electrode base plate.

[0022] Beneficial effects: By setting the insulating sealing element as a first ring and a second ring sleeved on the outside of the electrode post body, the first ring adapts to the first clearance hole and the second ring fills the gap between the cover body and the electrode post base plate, the sealing integrity of the assembly gap is improved, and the insulation reliability and sealing effect of the cell cover plate assembly are guaranteed.

[0023] Thirdly, the present invention also provides a battery cell, comprising: the aforementioned battery cell cover assembly.

[0024] Beneficial effects: The battery cell of the present invention includes the battery cell cover assembly as described above, and has all the beneficial technical effects of the battery cell cover assembly, which will not be repeated here. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is an exploded view of a battery cell cover assembly according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the pole post in a pre-assembled state according to an embodiment of the present invention; Figure 3 for Figure 2 A schematic diagram of the central pole in its assembled state; Figure 4 for Figure 2 Cross-sectional view of the central pole; Figure 5 for Figure 2 Side view of the central pole; Figure 6 This is a schematic diagram of a battery cell cover assembly in a pre-assembled state according to an embodiment of the present invention; Figure 7 for Figure 6 Cross-sectional view from the perspective of the center line AA; Figure 8 for Figure 6 Cross-sectional view from the perspective of the middle BB line; Figure 9 This is a schematic diagram of the structure of a battery cell cover assembly in an assembled state according to an embodiment of the present invention; Figure 10 for Figure 9 Cross-sectional view from the CC perspective; Figure 11 for Figure 9 Cross-sectional view from the DD perspective.

[0027] Explanation of reference numerals in the attached figures: 1. Terminal post; 101. Terminal post body; 1011. First conductive section; 1012. Second conductive section; 1013. Bending and flanged edge; 102. Terminal post base plate; 2. Cover body; 201. First clearance hole; 3. Plastic part; 301. Second clearance hole; 3011. Stepped part; 4. Insulating seal; 401. First ring layer; 402. Second ring layer. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] The following is combined Figures 1 to 11 The following describes embodiments of the present invention. For ease of description thereafter, as... Figure 1 As shown, a spatial rectangular coordinate system is established: the height direction of pole post 1 is denoted as the Z direction, the length direction of pole post 1 is denoted as the Y direction, and the width direction of pole post 1 is denoted as the X direction.

[0030] According to embodiments of the present invention, in one aspect, such as Figures 2 to 5 As shown, an electrode post 1 is provided, including an electrode post body 101.

[0031] Specifically, the electrode body 101 has a first conductive segment 1011 and a pair of second conductive segments 1012 connected to each other. Along the Y direction, the pair of second conductive segments 1012 are located on opposite sides of the first conductive segment 1011. The upper end surface of the first conductive segment 1011 is provided with bent flanges 1013 on opposite sides in the X direction. The electrode 1 includes a pre-assembled state and an assembled state. In the pre-assembled state, the bent flanges 1013 extend along the Z direction. In the assembled state, the pair of bent flanges 1013 bend away from each other and extend along the X direction after bending. Along the Z direction, the upper end surfaces of the first conductive segment 1011 and the second conductive segment 1012 in the Z direction are flush with the upper surface of the bent flanges 1013. On the projection plane perpendicular to the Z direction, the orthographic projection of the electrode body 101 is in the shape of a racetrack.

[0032] This invention, through the design of the electrode body 101 as a structure containing a first conductive segment 1011 and a pair of second conductive segments 1012, and by providing bent flanges 1013 on both sides of the first conductive segment in the X direction, which are pre-extended in the Z direction and bent away from each other during assembly and extended in the X direction, ensures that the orthographic projection of the electrode 1 is racetrack-shaped to accommodate the width limitation of the blade cell cover plate, and avoids the problem of insufficient filler when the convex edge of the semicircular part of the traditional racetrack-shaped electrode 1 is turned outward. This allows the bent flanges 1013 to completely fit the plastic, while reducing the pulling of the material at the root of the electrode 1 during the outward turning process, effectively improving the yield rate of the cell cover plate and the cell, ensuring the flatness of the upper surface of the electrode 1, and retaining the advantages of the traditional flanged cover plate in terms of simplicity and reliability. Furthermore, the improved flatness of the upper surface of the electrode 1 also helps to improve the subsequent welding quality of the electrode 1 and the busbar.

[0033] It should be noted that the reason why the orthographic projection of the pole body 101 in the assembled state appears as a racetrack shape on the projection plane perpendicular to the Z direction is because the orthographic projection shape of the first conductive segment 1011 on the projection plane perpendicular to the Z direction is a rectangle extending along the Y direction, and the orthographic projection shape of the second conductive segment 1012 on the projection plane perpendicular to the Z direction is a semicircle. Specifically, along the X direction, the width of the rectangle is less than the diameter of the semicircle, and the sum of the width of the rectangle and the width of the pair of bent flanges 1013 in the assembled state is equal to the diameter of the semicircle.

[0034] It should be noted that the pre-assembly state in this embodiment refers to the state before the electrode post 1 has been bent and flanged 1013 and each component has maintained its initial structure. The assembly state refers to the final state in which the bending and flanging 1013 of the electrode post 1 has been bent and shaped in a direction away from each other and has been adapted and assembled with other components of the cell cover assembly.

[0035] In one embodiment, in the pre-assembled state, the upper surfaces of the first conductive segment 1011 and the second conductive segment 1012 are flush in the Z direction. It can be understood that making the upper surfaces of the first conductive segment 1011 and the second conductive segment 1012 flush in the Z direction during pre-assembly provides a stable reference for the precise bending of the bending flange 1013 during assembly, ensuring that the upper surface of the electrode post 1 is flush after bending, further improving the flatness of the electrode post 1 and the assembly accuracy of the cover plate, and ensuring sealing effect and cell yield.

[0036] In one embodiment, such as Figure 5 As shown, in the pre-assembled state, along the Z direction, the height of the bent flange 1013 is h1, and the height of the second conductive segment 1012 is h2. The relationship between h1 and h2 satisfies: 0.2 ≤ h1 / h2 ≤ 0.4. It can be understood that this embodiment of the invention limits the ratio of the height h1 of the bent flange 1013 to the height h2 of the second conductive segment 1012 to between 0.2 and 0.4. This ensures that the bent flange 1013 has sufficient material for reliable folding and sealing, while also preventing excessive height from pulling on the root of the electrode post 1 during folding, further guaranteeing the flatness of the electrode post 1 and the yield rate of the cover plate.

[0037] It is understood that the ratio of h1 / h2 can be, but is not limited to, 0.2, 0.22, 0.25, 0.27, 0.3, 0.31, 0.34, 0.38, 0.39, 0.4 or any value between the two.

[0038] In one embodiment, such as Figure 4 As shown, in the pre-assembled state, along the X direction, the width of the first conductive segment 1011 is n, and the width of the bent flange 1013 is m. The relationship between n and m satisfies: 0.15 ≤ m / n ≤ 0.25. This embodiment of the invention limits the ratio of the width n of the first conductive segment 1011 to the width m of the bent flange 1013 in the pre-assembled state to between 0.15 and 0.25. This ensures that the bent flange 1013 has sufficient material for a tight seal, while avoiding excessive width that could lead to stress concentration during bending, thus ensuring the structural stability of the pole 1 and the assembly reliability of the cover plate.

[0039] It is understood that the ratio of m / n can be, but is not limited to, 0.15, 0.16, 0.17, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25 or any value between the two.

[0040] In one embodiment, such as Figures 2 to 5As shown, the electrode post 1 also includes an electrode post base plate 102, which is located at the end of the electrode post body 101 away from the bent flange 1013. On a projection plane perpendicular to the Z direction, the orthographic projection of the electrode post body 101 falls within the orthographic projection range of the electrode post base plate 102; and / or, on a projection plane perpendicular to the Z direction, the orthographic projection shape of the first conductive segment 1011 is rectangular, and the orthographic projection shape of the second conductive segment 1012 is semi-circular. It can be understood that by setting the electrode post base plate 102 at the end of the electrode post body 101 away from the bent flange 1013, and ensuring that the orthographic projection of the electrode post body 101 falls within the orthographic projection range of the electrode post base plate 102, the embodiments of the present invention can enhance the overall structural stability of the electrode post 1, provide stable support for the assembly of the electrode post 1, and improve the fitting accuracy between the electrode post 1 and other components of the battery cell, further ensuring the sealing effect of the cover and the reliability of the battery cell.

[0041] According to an embodiment of the present invention, on the other hand, such as Figure 1 , Figures 6 to 11 As shown, a cell cover assembly is also provided, including: a cover body 2, a plastic part 3, and the aforementioned electrode post 1.

[0042] Specifically, the cover body 2 has a first surface and a second surface that are arranged opposite to each other along the Z direction, and the cover body 2 has a first clearance hole 201 that is arranged through the Z direction; the plastic part 3 is located on the first surface, and the plastic part 3 has a second clearance hole 301 that is arranged through the Z direction and communicates with the first clearance hole 201; a portion of the pole body 101 is inserted into the first clearance hole 201 and the second clearance hole 301, and a pair of stepped portions 3011 are formed on the hole wall that is arranged opposite to each other along the X direction. In the assembled state, the pair of stepped portions 3011 are arranged in a one-to-one correspondence with a pair of bent flanges 1013. Along the Z direction, the lower surface of the bent flange 1013 abuts against the upper surface of the stepped portion 3011.

[0043] The battery cell cover assembly of this invention has a plastic part 3 with a stepped portion 3011 that corresponds to the bent flange 1013 of the electrode post 1 in the assembled state. This achieves precise positioning and reliable sealing between the electrode post 1 and the plastic part 3. Furthermore, the optimized structure of the electrode post 1 avoids problems such as insufficient filler and material pulling during bending, thereby improving the assembly accuracy, sealing reliability and overall yield of the cover assembly.

[0044] In one embodiment, such as Figure 1 and Figure 4As shown, in the assembled state, the width of the stepped portion 3011 and the length of the bent flange 1013 in the X direction are equal, as are their lengths in the Y direction. It can be understood that by making the width and length of the bent flange 1013 equal to the width and length of the stepped portion 3011 in the assembled state, this embodiment of the invention increases the contact area between the two, improves the fit and sealing performance and the uniformity of stress distribution, avoids localized stress concentration or sealing gaps, and further ensures the assembly stability of the cell cover assembly and the reliability of the cell.

[0045] In one embodiment, such as Figures 1 to 5 As shown, the pole post 1 also includes a pole post base plate 102, which is located at the end of the pole post body 101 away from the bent flange 1013. The pole post base plate 102 and the second surface are spaced apart. It can be understood that in this embodiment of the invention, the pole post base plate 102 and the second surface of the cover body 2 are spaced apart, which not only maintains the structural stability and assembly support of the pole post 1, but also avoids direct contact between the base and the cover body 2 to prevent interference, thus ensuring the assembly coordination of the various components of the cover assembly and further improving the sealing effect and assembly yield.

[0046] In one embodiment, such as Figure 1 As shown, the cell cover assembly also includes an insulating seal 4. The insulating seal 4 includes a first ring 401 and a second ring 402 connected along the Z direction. The first ring 401 and the second ring 402 are sleeved on the outside of the electrode body 101. The first ring 401 is located inside the first clearance hole 201, and the second ring 402 is located between the cover body 2 and the electrode base plate 102. In this embodiment of the invention, by setting the insulating seal 4 as a first ring 401 and a second ring 402 sleeved on the outside of the electrode body 101, the first ring 401 adapts to the first clearance hole 201, and the second ring 402 fills the gap between the cover body 2 and the electrode base plate 102, thereby improving the sealing integrity of the assembly gap and ensuring the insulation reliability and sealing effect of the cell cover assembly.

[0047] According to an embodiment of the present invention, another aspect provides a battery cell, including the aforementioned battery cell cover assembly.

[0048] Beneficial effects: The battery cell of the present invention includes the battery cell cover assembly as described above, and has all the beneficial technical effects of the battery cell cover assembly, which will not be repeated here.

[0049] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. An electrode post, characterized in that, include: The electrode body has a first conductive segment and a pair of second conductive segments connected together. Along the Y direction, the pair of second conductive segments are located on opposite sides of the first conductive segment. The upper end surface of the first conductive segment is provided with bent flanges on opposite sides in the X direction. The pole includes a pre-assembled state and an assembled state. In the pre-assembled state, the bent flange extends along the Z direction. In the assembled state, the pair of bent flanges bend away from each other and extend along the X direction after bending. Along the Z direction, the upper end faces of the first conductive segment and the second conductive segment are flush with the upper surface of the bent flange. On the projection plane perpendicular to the Z direction, the orthographic projection of the pole body is in the shape of a racetrack.

2. The pole post according to claim 1, characterized in that, In the pre-assembled state, the upper surfaces of the first conductive segment and the second conductive segment are flush in the Z direction.

3. The pole post according to claim 2, characterized in that, In the pre-assembled state, along the Z direction, the height of the bent flange is h1, and the height of the second conductive segment is h2. The relationship between h1 and h2 satisfies: 0.2≤h1 / h2≤0.

4.

4. The pole post according to claim 3, characterized in that, In the pre-assembled state, along the X direction, the width of the first conductive segment is n, and the width of the bent flange is m. The relationship between n and m satisfies: 0.15≤m / n≤0.

25.

5. The pole post according to any one of claims 1 to 4, characterized in that, The electrode post also includes an electrode post base plate, which is located at the end of the electrode post body away from the bent flange. On a projection plane perpendicular to the Z direction, the orthographic projection of the electrode post body falls within the orthographic projection range of the electrode post base plate; and / or, on a projection plane perpendicular to the Z direction, the orthographic projection shape of the first conductive segment is rectangular, and the orthographic projection shape of the second conductive segment is semi-circular.

6. A cell cover assembly, characterized in that, include: The cover body has a first surface and a second surface that are disposed opposite to each other along the Z direction, and the cover body has a first clearance hole that is disposed through the Z direction. A plastic part is located on the first surface, and the plastic part has a second clearance hole that is disposed through the Z direction and communicates with the first clearance hole; According to any one of claims 1 to 5, the pole body is partially inserted into the first clearance hole and the second clearance hole. The second clearance hole has a pair of stepped portions protruding from its hole wall along the X direction. In the assembled state, the pair of stepped portions are arranged in correspondence with the pair of bent flanges. Along the Z direction, the lower surface of the bent flange abuts against the upper surface of the stepped portion.

7. The cell cover assembly according to claim 6, characterized in that, In the assembled state, the width of the stepped portion and the length of the bent flange in the X direction are equal, as are their lengths in the Y direction.

8. The cell cover assembly according to claim 6, characterized in that, The pole also includes a pole base plate, which is located at the end of the pole body away from the bent flange, and the pole base plate is spaced apart from the second surface.

9. The cell cover assembly according to claim 8, characterized in that, The cell cover assembly further includes an insulating seal, which includes a first ring and a second ring connected along the Z direction. The first ring and the second ring are sleeved on the electrode body. The first ring is located inside the first clearance hole, and the second ring is located between the cover body and the electrode base plate.

10. A battery cell, characterized in that, include: The cell cover assembly according to any one of claims 6 to 9.

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