Composite electrode post and cell cover
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-22
- Publication Date
- 2026-08-14
AI Technical Summary
[0004]然而，上述的平面结合界面设计及相关复合极柱，存在界面结合强度不足的问题：当极柱在后续使用过程中受到高温(导致材料膨胀系数差异显著)或承受较大轴向拉力(如电池组装或使用中的应力)时，铜铝结合面处容易发生断裂失效，严重影响电池的安全性与可靠性
[0024]上述复合极柱以及电芯盖板，通过在第一柱体部和第二柱体部之间的接触面配置卡接部与凹陷部，通过卡接部和凹陷部的配合形成极柱轴向的物理限位阻挡；当极柱受到沿极柱轴向两侧的拉力(如电池组装或使用中的应力)时，卡接部和凹陷部的配合区域能有效抵抗第一金属件和第二金属件的结合界面之间的分离趋势，显著提高抗拉强度和抗剪切强度，从根本上解决了相关技术中结合界面强度不足的问题，提高复合极柱的可靠性和安全性。
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Figure CN224637373U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to composite terminals and cell covers. Background Technology
[0002] With the development of power battery technology, the performance and cost requirements for battery terminals are constantly increasing. In order to balance conductivity, cost and lightweight, copper-aluminum composite structure negative electrode terminal technology has emerged. This technology utilizes the copper layer to provide excellent conductivity, while the aluminum layer achieves lightweight and reduces costs.
[0003] In related technologies, to achieve the final shape and dimensional accuracy of copper-aluminum composite poles, a turning process is usually added after the composite structure is formed. Meanwhile, to facilitate the implementation of the composite process, the interface between the copper and aluminum materials is typically designed as a simple plane.
[0004] However, the aforementioned planar interface design and related composite terminals have the problem of insufficient interface bonding strength: when the terminals are subjected to high temperatures (leading to significant differences in the coefficient of thermal expansion of materials) or large axial tensile forces (such as stress during battery assembly or use) during subsequent use, the copper-aluminum interface is prone to fracture failure, which seriously affects the safety and reliability of the battery. Summary of the Invention
[0005] Therefore, it is necessary to provide a composite electrode post and cell cover plate to address the above problems, thereby increasing the reliability of the copper-aluminum bonding and simplifying the molding process, eliminating the need for machining.
[0006] A composite pole includes a first metal part and a second metal part joined to the first metal part along the pole axis z;
[0007] The first metal part includes a first cylindrical portion and at least one snap-fit portion extending from the first cylindrical portion toward the second metal part in the pole axis z;
[0008] The second metal part includes a second column portion and an annular plate portion disposed on the outer periphery of the second column portion and extending in the radial x direction of the pole post. The second column portion has a recess portion that engages with the locking portion, and the locking portion and the recess portion that engage with each other form a limiting block in the axial z direction and the radial x direction of the pole post.
[0009] Along the radial x direction of the pole post, the outer edge of the annular plate portion protrudes circumferentially to form an extension;
[0010] The extension has a first end face and a second end face opposite each other in the pole column axis z, the first end face being closer to the first metal member in the pole column axis z than the second end face, and the ring plate has a third end face and a fourth end face opposite each other in the pole column axis z, the third end face being closer to the first metal member in the pole column axis z than the fourth end face, wherein the first end face and the third end face form a continuous plane in the pole column radial x.
[0011] The thickness of the extension portion along the pole axis z is less than the thickness of the annular plate portion along the pole axis z.
[0012] The outer contour of the first column portion projected onto a plane perpendicular to the pole axis z and the outer contour of the second column portion projected onto a plane perpendicular to the pole axis z have overlapping boundaries.
[0013] In one embodiment, the recess includes a first protrusion protruding toward the first metal member and a second protrusion surrounding the first protrusion, with a recessed area formed between the first protrusion and the second protrusion;
[0014] The snap-fit portion has an annular protrusion that protrudes toward the recessed area, and the annular protrusion fits into the recessed area.
[0015] In one embodiment, the first metal part is made of aluminum and the second metal part is made of copper.
[0016] In one embodiment, the first column portion has a first groove on one end face away from the second column portion along the z-axis of the pole column.
[0017] In one embodiment, the second column portion has a second groove on one end face away from the first column portion along the z-axis of the pole column.
[0018] In one embodiment, the width of the extension in the radial direction x of the pole post is w2, and the width w2 satisfies: 0.5mm≤w2≤3mm.
[0019] In one embodiment, the thickness of the annular plate portion along the pole column axis z is t1, and the thickness t1 satisfies: 0.8mm≤t1≤3mm.
[0020] In one embodiment, the thickness of the extension in the pole axis z is t2, and the thickness difference between the annular plate and the extension is K, where K = t1 - t2.
[0021] The thickness difference K satisfies: 0.3mm≤K≤0.5*t1.
[0022] In one embodiment, the ring width of the annular plate portion in the radial x direction of the pole post is w1, and the width w1 satisfies: 1.5mm≤w1≤3mm.
[0023] On the other hand, this application provides a cell cover plate, including the aforementioned composite electrode post.
[0024] The aforementioned composite electrode post and cell cover plate, by configuring a snap-fit portion and a recessed portion on the contact surface between the first and second electrode posts, form a physical limiting barrier along the axial direction of the electrode post through the cooperation of the snap-fit portion and the recessed portion; when the electrode post is subjected to tensile force along both sides of the electrode post axial direction (such as stress during battery assembly or use), the cooperation area of the snap-fit portion and the recessed portion can effectively resist the separation tendency between the bonding interface of the first and second metal parts, significantly improving tensile strength and shear strength, fundamentally solving the problem of insufficient bonding interface strength in related technologies, and improving the reliability and safety of the composite electrode post. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of the overall structure of the negative electrode post of this application.
[0026] Figure 2 This is a schematic diagram of the overall structure of the negative electrode post from another perspective.
[0027] Figure 3 This is a top view of the negative electrode post in the second direction of this application.
[0028] Figure 4 for Figure 3 AA section view in the image.
[0029] Figure 5 This is a schematic diagram of the structure of the first metal part of this application.
[0030] Figure 6 This is a schematic diagram of the structure of the second metal part of this application.
[0031] Figure 7 for Figure 4 A schematic diagram of the various parameters.
[0032] Figure 8 This is a schematic diagram of the negative electrode post structure before stamping and trimming in one embodiment of this application.
[0033] Figure 9 This is a top view of the negative electrode post before the stamping and trimming in the second direction of this application.
[0034] Figure 10 Figure 9 BB section view in the middle.
[0035] Wherein: 100, first metal part; 200, second metal part; 300, first groove; 400, extension; 500, second groove; 600, outer contour; 700, offset area;
[0036] 110. First column part; 120. Snap-fit part;
[0037] 120a, Annular protrusion;
[0038] 210. Second column section; 220. Ring plate section;
[0039] 211. Depression;
[0040] 211a, First protrusion; 211b, Second protrusion; 211c, Depression area;
[0041] 220a, Third end face; 220b, Fourth end face;
[0042] 400a, First end face; 400b, Second end face;
[0043] x, radial direction of the pole; z, axial direction of the pole. Detailed Implementation
[0044] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.
[0045] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0046] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0047] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0048] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0049] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.
[0050] See Figures 1-7 The diagram shows a structural schematic of a composite pole in one embodiment of this application.
[0051] This application provides a composite pole, including a first metal part 100 and a second metal part 200 joined to the first metal part 100 in the pole axis z;
[0052] The first metal member 100 includes a first column portion 110 and at least one snap-fit portion 120 extending from the first column portion 110 toward the second metal member 200 in the pole column axial direction z.
[0053] The second metal part 200 includes a second column portion 210 and an annular plate portion 220 disposed on the outer periphery of the second column portion 210 and extending in the radial x direction of the pole post. The second column portion 210 has a recessed portion 211 that engages with the locking portion 120, and the locking portion 120 and the recessed portion 211 that engage with each other form limiting blocks in the pole post axial direction z and the pole post radial direction x.
[0054] In the radial x direction of the pole post, the outer edge of the annular plate portion 220 protrudes circumferentially to form an extension portion 400;
[0055] The extension 400 has a first end face 400a and a second end face 400b opposite each other in the pole column axis z. The first end face 400a is closer to the first metal member 100 in the pole column axis z than the second end face 400b. The ring plate portion 220 has a third end face 220a and a fourth end face 220b opposite each other in the pole column axis z. The third end face 220a is closer to the first metal member 100 in the pole column axis z than the fourth end face 220b. The first end face 400a and the third end face 220a form a continuous plane in the pole column radial direction x.
[0056] The thickness of the extension 400 in the pole axis z is less than the thickness of the annular plate portion 220 in the pole axis z.
[0057] The outer contour of the first column portion 110 projected onto a plane perpendicular to the pole axis z and the outer contour of the second column portion 210 projected onto a plane perpendicular to the pole axis z have overlapping boundaries; thereby, the outer surfaces of the first column portion 110 and the second column portion 210 fit together as a whole to form the outer surface of the cylindrical column portion of the pole.
[0058] In some embodiments, the recessed portion 211 includes a first protrusion 211a protruding toward the first metal member 100 and a second protrusion 211b surrounding the first protrusion 211a, and a recessed region 211c is formed between the first protrusion 211a and the second protrusion 211b; the snap-fit portion 120 has an annular protrusion 120a protruding toward the recessed region, and the annular protrusion is fitted into the recessed region 211c.
[0059] like Figure 3As shown, the orthogonal projection of the first column portion 110 on the pole column axis z forms an outer contour 600. The area outside the outer contour 600 is pure copper, and the area inside is copper-aluminum composite. The first metal part 100 is made of aluminum, and the second metal part 200 is made of copper.
[0060] Furthermore, such as Figure 5 As shown, the snap-fit part 120 is an annular protrusion;
[0061] like Figure 6 As shown, the recessed portion 230 includes a first protrusion 231 located on the top surface and an annular second protrusion 232 located on the circumferential surface, the first protrusion 231 and the second protrusion 232 forming a recessed area;
[0062] The shape of the first arc-shaped surface 121 corresponds to the shape of the first protrusion 231, and the shape of the second arc-shaped surface 122 corresponds to the shape of the second protrusion 232, so that the annular protrusion is embedded in the recessed area.
[0063] In some embodiments, a first groove 300 is provided at the top of the first column portion 110 in the pole column axis z; it can be understood that the top here refers to the end face of the first column portion 110 away from the second column portion 210 in the pole column axis z.
[0064] In some embodiments, a second groove 500 is provided at the bottom of the second column portion 210 in the pole column axis z; it can be understood that the bottom here refers to the end face of the second column portion 210 away from the first column portion 110 in the pole column axis z.
[0065] In some embodiments, the thickness of the annular plate portion 220 in the pole column axial direction z is t1, and the thickness t1 satisfies: 0.8mm≤t1≤3mm;
[0066] Furthermore, the thickness of the extension (400) in the pole column axis z is t2, and the thickness difference between the ring plate portion 220 and the extension 400 is K, and K = t1 - t2; the thickness difference K satisfies: 0.3mm ≤ K ≤ 0.5 * t1.
[0067] The experiment was conducted based on the thickness t1 of the annular plate portion 220 along the pole column axis z. The experimental data are shown in Table 1.
[0068] Table 1
[0069]
[0070] As shown in Table 1, when t1 < 0.8 mm, the support strength is insufficient; when t1 > 3 mm, the material consumption is large and the cost is high.
[0071] An experiment was conducted based on the thickness difference K between the annular plate portion 220 and the extension portion 400. The experimental data are shown in Table 2.
[0072] Table 2
[0073]
[0074] As shown in Table 2, when K < 0.3 mm, the forming characteristics of the step are not obvious and the effect is not good; when K > 0.5 * t1 (mm), the forming of the step is difficult.
[0075] In some embodiments, the ring width of the ring plate portion 220 in the radial x direction of the pole post is w1, and the width w1 satisfies: 1.5mm≤w1≤3mm;
[0076] Furthermore, experiments were conducted based on the width w1 of the annular plate 220, and the experimental data are shown in Table 3:
[0077] Table 3
[0078]
[0079] Based on Table 3, when w1 < 1.5 mm, the step 400 is insufficient to support the sealing ring; when w1 > 3 mm, it results in a waste of lateral space.
[0080] In some embodiments, the width of the extension 400 in the radial x direction of the pole post is w2, and the width w2 satisfies: 0.5mm≤w2≤3mm;
[0081] Furthermore, experiments were conducted based on the width w2 of the extension 400, and the experimental data are shown in Table 4:
[0082] Table 4
[0083]
[0084] Based on Table 4, it can be seen that when w2 < 0.5 mm, the forming characteristics of step 400 are not obvious and the effect is not good; when w2 > 3 mm, the base plate is prone to deformation during stamping and trimming.
[0085] In practical applications, copper-aluminum composite plates are limited by their processing technology. The proportion of copper thickness to total thickness cannot exceed 50%, but it cannot be less than 20%. That is, the "volume of copper material in the finished electrode + volume of copper removed by cutting edges" cannot exceed half of the "volume of copper material in the finished electrode + volume of copper removed by cutting edges + volume of aluminum material in the finished electrode", and cannot be less than 20%.
[0086] Meanwhile, the volume of the bias region 700 is: S*(t1-t2);
[0087] S represents the surface area of the bias region 700, and t1-t2 represents the height of the bias region 700 along the z-axis of the pole column.
[0088] Therefore, in the negative electrode post, the volume of aluminum material in the aluminum material area of the copper-aluminum composite part is V1, and the total volume of copper material in the copper material area of the copper material part and the copper-aluminum composite part is V2.
[0089] Volumes V1, V2, and V3 of the offset region 700 together satisfy:
[0090]
[0091] In some embodiments, the distance by which the offset region 700 is offset outward in the first direction x (the distance between the outer edge of the offset region 700 and the outer edge of the plate structure 200) is w3, and the distance w3 satisfies: 1mm≤w3≤3mm.
[0092] An experiment was conducted based on an outward offset distance w3 from the offset region 700 in the first direction x. The experimental data are shown in Table 5.
[0093] Table 5
[0094]
[0095] Based on the data in Table 5, it can be seen that when w3 < 1 mm, the reserved cutting edge width in the offset area 700 is insufficient, making cutting difficult; when w3 > 3 mm, there is too much excess material in the offset area 700, resulting in material waste.
[0096] In other embodiments, a cell cover plate is also included, comprising the aforementioned composite electrode post.
[0097] In summary, the composite electrode of this application, by configuring a snap-fit portion 120 and a recessed portion 230 on the contact surface between the first electrode portion 110 and the second electrode portion 210, forms a physical limiting barrier in the axial direction of the electrode through the cooperation of the snap-fit portion 120 and the recessed portion 230. When the electrode is subjected to tensile force on both sides along the axial direction of the electrode (such as stress during battery assembly or use), the cooperation area of the snap-fit portion 120 and the recessed portion 230 can effectively resist the separation tendency between the bonding interface of the first metal part 100 and the second metal part 200, significantly improving tensile strength and shear strength, fundamentally solving the problem of insufficient bonding interface strength in related technologies, and improving the reliability and safety of the composite electrode.
[0098] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0099] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A composite pole, characterized by, It includes a first metal part and a second metal part that is joined to the first metal part in the z-axis direction of the pole column; The first metal part includes a first cylindrical portion and at least one snap-fit portion extending from the first cylindrical portion toward the second metal part in the pole axis z; The second metal part includes a second column portion and an annular plate portion disposed on the outer periphery of the second column portion and extending in the radial x direction of the pole post. The second column portion has a recess portion that engages with the locking portion, and the locking portion and the recess portion that engage with each other form a limiting block in the axial z direction and the radial x direction of the pole post. Along the radial x direction of the pole post, the outer edge of the annular plate portion protrudes circumferentially to form an extension; The extension has a first end face and a second end face opposite each other in the pole column axis z, the first end face being closer to the first metal member in the pole column axis z than the second end face, and the ring plate has a third end face and a fourth end face opposite each other in the pole column axis z, the third end face being closer to the first metal member in the pole column axis z than the fourth end face, wherein the first end face and the third end face form a continuous plane in the pole column radial x. The thickness of the extension portion along the pole axis z is less than the thickness of the annular plate portion along the pole axis z. The outer contour of the first column portion projected onto a plane perpendicular to the z-axis of the pole column and the outer contour of the second column portion projected onto a plane perpendicular to the z-axis of the pole column have overlapping boundaries.
2. The composite pole according to claim 1, wherein The recessed portion includes a first protrusion protruding toward the first metal part and a second protrusion surrounding the first protrusion, with a recessed area formed between the first protrusion and the second protrusion; The snap-fit portion has an annular protrusion that protrudes toward the recessed area, and the annular protrusion fits into the recessed area.
3. The composite post of claim 1, wherein, The first metal part is made of aluminum, and the second metal part is made of copper.
4. The composite post of claim 1, wherein The first column portion has a first groove on one end face away from the second column portion along the z-axis of the pole column.
5. The composite post of claim 1, wherein The second column portion has a second groove on one end face away from the first column portion along the z-axis of the pole column.
6. The composite post of claim 1, wherein In the radial direction x of the pole post, the width of the extension is w2, and the width w2 satisfies: 0.5mm≤w2≤3mm.
7. The composite electrode according to claim 1, characterized in that, The thickness of the ring plate portion along the z-axis of the pole column is t1, and the thickness t1 satisfies: 0.8mm≤t1≤3mm.
8. The composite post of claim 7, wherein, The thickness of the extension in the pole column axis z is t2, and the thickness difference between the ring plate and the extension is K, where K = t1 - t2; The thickness difference K satisfies: 0.3mm≤K≤0.5*t1.
9. The composite post of claim 1, wherein, In the radial x direction of the pole post, the ring width of the ring plate is w1, and the width w1 satisfies: 1.5mm≤w1≤3mm.
10. An electrode cover plate, characterized by, Includes the composite pole as described in any one of claims 1-9.