Composite pole and battery

Abstract

The invention relates to the technical field of batteries, and particularly discloses a composite pole and a battery, and the composite pole comprises a copper material part and an aluminum material part. The copper material part comprises a plate body and a first column body, the aluminum material part comprises a second column body, and the second column body is connected with the first column body. The volume of the aluminum material part is S1, the volume of the copper material part is S2, and S2 / S1 is larger than or equal to 0.15 and smaller than or equal to 0.48. By controlling the S2 / S1 value to be within the range, it can be guaranteed that the composite pole can be smoothly formed in a cold heading mode, the forming yield is high, the size precision is high, and the machining cost is low. An annular flange is arranged on one side, deviating from the plate body, of the second column body, an included angle alpha is formed between the first wall surface and the second wall surface of the annular flange, the thickness of each part of the annular flange in the radial direction after riveting is uniform by limiting the value of alpha, the connection strength of the composite pole and the battery cover plate is relatively high, failure is not easy to occur, and the service life of the composite pole is prolonged. And demolding is facilitated during cold heading forming. The invention also provides a battery which comprises the composite pole.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and particularly to a composite terminal post and a battery. Background Art

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries, as power batteries, are widely used in electric vehicles and energy storage fields. People's requirements for the performance and safety of lithium-ion batteries are increasing day by day. A lithium-ion battery includes a housing, a battery stack, a positive terminal post, and a negative terminal post. The battery stack is disposed inside the housing, and the positive terminal post and the negative terminal post are integrated on the housing. By electrically connecting the positive terminal post and the negative terminal post to the positive tab and the negative tab of the battery stack, the positive and negative electrodes of the battery stack are led out to realize power supply to the outside or charging.

[0003] Generally, the negative terminal post often adopts a composite terminal post. The copper part in the composite terminal post is electrically connected to the negative tab of the battery stack, and the aluminum part in the composite terminal post is used for electrical connection with an external circuit. There are two common forming methods for the composite terminal post: First, a copper-aluminum composite plate can be used for machining, but the material utilization rate of this processing method is low and the cost is relatively high; Second, a copper-aluminum composite plate can be used for cold heading forming, but there are problems of poor forming accuracy and low forming rate in this processing method. Summary of the Invention

[0004] The purpose of the present invention is to provide a composite terminal post and a battery. The special size design of the composite terminal post can improve the forming yield rate when the composite terminal post is formed by cold heading, and has high dimensional accuracy and low processing cost.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] On the one hand, the present invention provides a composite terminal post, which includes:

[0007] A copper part, the copper part includes a plate body and a first column body that are connected to each other;

[0008] An aluminum part, the aluminum part includes a second column body, the second column body is connected to the first column body, and an intersection interface is formed between the second column body and the first column body;

[0009] Wherein, the volume of the aluminum part is S1, and the volume of the copper part is S2;

[0010] S1 and S2 satisfy: 0.15 ≤ S2 / S1 ≤ 0.48;

[0011] On one side of the second cylinder facing away from the plate body, there is an annular flange. The annular flange extends along the axial direction of the second cylinder. The annular flange has a first wall surface and a second wall surface in its radial direction. The first wall surface is close to the axis of the annular flange, and the second wall surface is flush with the circumferential side wall of the second cylinder and the circumferential side wall of the first cylinder;

[0012] There is an included angle α between the first wall surface and the second wall surface of the annular flange;

[0013] The value range of α is 0.5° ≤ α ≤ 3.0°.

[0014] Optionally, along the axial direction of the second cylinder, the distance between the mating interface and the end face of the plate body on the side close to the second cylinder is h;

[0015] The value range of h is 0.2 mm ≤ h ≤ 5 mm;

[0016] And / or, along the axial direction of the second cylinder, the height of the plate body is t, and the value range of t is 2 mm ≤ t ≤ 10 mm; the dimensional tolerance of t is less than or equal to ±0.2 mm.

[0017] Optionally, along the radial direction of the second cylinder, the thickness of the end of the annular flange facing away from the plate body is A; along the axial direction of the second cylinder, the height of the annular flange is B;

[0018] Among them, the following relationship is satisfied between A and B: 1.2 ≤ B / A ≤ 3;

[0019] The value range of A is 0.5 mm ≤ A ≤ 3 mm;

[0020] The value range of B is 1 mm ≤ B ≤ 5 mm.

[0021] Optionally, the inner side of the annular flange and the end face of the second cylinder on the side facing away from the plate body enclose a first groove. The first wall surface is the first groove side wall of the first groove, and the end face of the second cylinder on the side facing away from the plate body is the first groove bottom wall. The first groove side wall and the first groove bottom wall are transitioned through a first arc portion, and the radius of the first arc portion is R;

[0022] The value range of R is 0.1 mm ≤ R ≤ 0.5 mm.

[0023] Optionally, a second groove is provided on the first groove bottom wall. The second groove is in an inverted cone shape, and the diameter of the open end of the second groove is larger than the diameter of the groove bottom of the second groove.

[0024] Optionally, along the axial direction of the second cylinder, the depth of the second groove is e, and the value range of e is 0.5 mm ≤ e ≤ 5 mm.

[0025] Optionally, the second groove includes a second groove side wall and a second groove bottom wall, and there is an included angle k between the second groove side wall and the second groove bottom wall, where the value range of k is 5° ≤ k ≤ 60°;

[0026] And / or, the diameter of the second groove bottom wall is φd, and the value range of φd is 0.5 mm ≤ φd ≤ 10 mm.

[0027] Optionally, the second groove side wall and the first groove bottom wall are transitioned through a second arc portion, and the radius of the second arc portion is R1, where the value range of R1 is 0.1 mm ≤ R1 ≤ 2 mm.

[0028] Optionally, along the axial direction of the second cylinder, the distance between the mating interface formed between the first cylinder and the second cylinder and the second groove bottom wall is c;

[0029] The value range of c is 0.5 mm ≤ c ≤ 10 mm.

[0030] On the other hand, the present invention provides a battery, including the composite pole column in any of the above solutions.

[0031] The beneficial effects of the present invention are as follows:

[0032] The present invention provides a composite pole column, including a copper part and an aluminum part. The copper part includes a plate body and a first cylinder that are connected to each other, and the aluminum part includes a second cylinder that is connected to the first cylinder. Among them, the volume of the aluminum part is S1, and the volume of the copper part is S2, and S1 and S2 satisfy: 0.15 ≤ S2 / S1 ≤ 0.48. By controlling the value of S2 / S1 within the above range, it can be ensured that the composite pole column can be successfully cold-heading formed, with a high forming yield, relatively high dimensional accuracy, meeting product requirements, and low processing costs. A ring-shaped flange is provided on the side of the second cylinder facing away from the plate body, and there is an included angle α between the first wall surface and the second wall surface of the ring-shaped flange, where the value range of α is 0.5° ≤ α ≤ 3.0°. By restricting the value of α within the above range, it can be ensured that the thickness of each part of the ring-shaped flange along its radial direction is uniform after riveting, the connection strength between the composite pole column and the battery cover plate is relatively high, and it is convenient to demold during the cold-heading forming of the composite pole column, and the appearance of the composite pole column is good.

[0033] The present invention also provides a battery, including a housing, a pole group, and a battery cover plate. An opening is provided on one side of the housing, the pole group is installed into the housing through the opening, the battery cover plate is connected to the opening of the housing, and the pole group is encapsulated in a sealed space by the housing and the battery cover plate. The above composite pole column is integrated on the battery cover plate. By adopting the above composite pole column, the reliability of the battery is ensured to be relatively high, and the battery cover plate is not likely to fail. Description of the Drawings

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the content of the embodiments of the present invention and these drawings.

[0035] Figure 1 It is a schematic structural diagram of the composite pole column (before riveting) provided in the embodiment of the present invention;

[0036] Figure 2 It is a sectional view of the composite pole column (before riveting) provided in the embodiment of the present invention;

[0037] Figure 3 It is Figure 2 a partial enlarged view of part A in

[0038] Figure 4 It is a schematic structural diagram of the composite pole column (after riveting) provided in the embodiment of the present invention;

[0039] Figure 5 It is a sectional view of the composite pole column (after riveting) provided in the embodiment of the present invention;

[0040] Figure 6 It is a top view of the battery cover plate provided in the embodiment of the present invention;

[0041] Figure 7 It is Figure 6 a sectional view of the B-B section in

[0042] Figure 8 It is Figure 7 a partial enlarged view of part C in

[0043] Figure 9 It is an exploded view of the battery cover plate provided in the embodiment of the present invention.

[0044] In the figure:

[0045] 100. Composite pole column; 110. Copper part; 111. Plate body; 112. First column; 1121. Junction interface; 120. Aluminum part; 121. Second column; 122. Annular flange; 1221. First wall surface; 1222. Second wall surface; 123. First groove; 1231. First groove side wall; 1232. First groove bottom wall; 124. Second groove; 1241. Second groove side wall; 1242. Second groove bottom wall; 200. Cover plate body; 300. Pure aluminum pole column; 400. First plastic part; 500. Second plastic part; 600. Sealing part. Detailed implementation manners

[0046] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions. Moreover, the first feature being "above", "over" and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicating that the first feature has a lower horizontal height than the second feature.

[0048] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected" and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0049] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0050] As Figures 1-3 shown, this embodiment provides a composite pole column 100, which can be formed by cold heading using a mold and composite plates, with high forming yield, high dimensional accuracy, and low processing cost.

[0051] Specifically, the composite plate includes a copper material layer and an aluminum material layer. Therefore, the composite pole 100 formed by cold heading using a mold includes a copper part 110 and an aluminum part 120. The copper part 110 includes a plate body 111 and a first cylinder 112 connected to each other. The aluminum part 120 includes a second cylinder 121, and the second cylinder 121 is connected to the first cylinder 112, and an intersection interface 1121 is formed between the second cylinder 121 and the first cylinder 112.

[0052] Among them, the volume of the aluminum part 120 is S1, and the volume of the copper part 110 is S2. S1 and S2 satisfy: 0.15 ≤ S2 / S1 ≤ 0.48. For example, the value of S2 / S1 can be 0.15, 0.20, 0.30, 0.40, 0.48, etc. Since the fluidity of the aluminum material is better than that of the copper material, by controlling the value of S2 / S1 within the above range, it can be ensured that the composite pole 100 can be successfully cold-headed. Otherwise, when the value of S2 / S1 is small, it may not be possible to form the first cylinder 112 of the copper part 110, and the intersection interface 1121 will be located at the plate body 111, and the resistance of the composite pole 100 is large, and the overcurrent capacity is poor; when the value of S2 / S1 is too large, the volume of the copper part 110 is large, and the material fluidity of the composite plate is poor, resulting in the composite pole 100 being unable to be cold-headed. Even if it is barely formed, the dimensional accuracy of the formed composite pole 100 is poor and does not meet the product requirements.

[0053] Furthermore, referring to Figure 2 , an annular flange 122 is provided on the side of the second cylinder 121 facing away from the plate body 111, and the annular flange 122 extends along the axial direction of the second cylinder 121 ( Figure 1 the Z-axis direction shown in Figure 4 and Figure 5 ). When the composite pole 100 is assembled with other components on the battery cover plate, it is necessary to rivet and press the annular flange 122 to make it deformed, so as to fix the composite pole 100 on the cover body 200 of the battery cover plate.

[0054] Continuing to refer to Figure 2 , the annular flange 122 has a first wall surface 1221 and a second wall surface 1222 along its radial direction ( Figure 1 the X-axis direction shown in

[0055] By limiting the value of α within the above range, it can be ensured that the annular flange 122 is radially ( Figure 5 The thickness of the composite pole 100 is uniform at various locations (in the X-axis direction in the figure), the connection strength between the composite pole 100 and the battery cover is high, and the composite pole 100 is easy to demold during cold heading, and the first wall surface 1221 and the second wall surface 1222 of the annular flange 122 will not be scratched, and the appearance of the composite pole 100 is good. Otherwise, if the value of α is too small, the flow of the aluminum material layer during the cold heading process is affected, and the annular flange 122 is easily scratched during demolding; if the value of α is too large, it will affect the uniformity of the thickness of the annular flange 122 and the battery cover after riveting, resulting in a decrease in the connection strength between the annular flange 122 and the battery cover, and a decrease in reliability.

[0056] Furthermore, along the radial direction of the second column 121, the thickness of the end of the annular flange 122 away from the plate body 111 is A; along the axial direction of the second column 121, the height of the annular flange 122 is B. Among them, A and B satisfy: 1.2≤B / A≤3. For example, the value of B / A can be 1.2, 1.5, 2.0, 2.5 or 3.0, etc. The value range of A is 0.5mm≤A≤3mm; the value range of B is 1mm≤B≤5mm. By limiting the value of B / A within the above range, the forming accuracy of the annular flange 122 is higher. Otherwise, when the value of B / A is too large or too small, after the composite pole 100 is cold headed, the dimensional accuracy of the annular flange 122 is poor, and defects such as collapsed edges are prone to occur.

[0057] Continue to see Figure 2 , along the axial direction of the second column 121, the distance between the interface 1121 between the first column 112 and the second column 121 and the end face of the plate 111 close to the second column 121 is h, and the value range of h is 0.2mm≤h≤5mm. For example, the value of h can be 0.2mm, 0.5mm, 1.0mm, 2.0mm, 3.0mm, 4.0mm or 5.0mm, etc. By limiting the value of h within the above range, the stress concentration position of the composite pole 100 is avoided from coinciding with the position of the interface 1121, thereby ensuring that the mechanical strength of the composite pole 100 is relatively large, the copper material part 110 and the aluminum material part 120 are not easily separated, and the reliability is relatively high. Among them, the stress concentration position of the above-mentioned composite pole 100 is: the connection position between the first column 112 and the plate 111. When the value of h is too small, the stress concentration position of the joint interface 1121 and the composite pole 100 is relatively close, and the first column 112 and the second column 121 at the joint interface 1121 have the risk of separation, which may easily cause the composite pole 100 to fall off the battery cover, reducing reliability. When the value of h is too large, the proportion of the copper material part 110 increases, resulting in increased costs and poor economic efficiency.

[0058] Furthermore, along the axial direction of the second column 121, the height of the plate 111 is t, and the value range of t is 2mm≤t≤10mm. For example, the value of t can be 2.0mm, 3.0mm, 5.0mm, 8.0mm or 10.0mm. It should be noted that the dimensional tolerance of t must be less than or equal to ±0.2mm. Otherwise, when the composite pole 100 is formed by cold heading, the mold may crack.

[0059] Continue to see Figure 1 and Figure 2 In this embodiment, the inner side of the annular flange 122 and the end surface of the second column 121 facing away from the plate body 111 form a first groove 123, that is, the first wall surface 1221 of the annular flange 122 is the first groove side wall 1231 of the first groove 123, and the end surface of the second column 121 facing away from the plate body 111 is the first groove bottom wall 1232. The first groove side wall 1231 and the first groove bottom wall 1232 are transitioned by a first arc portion, and the radius of the first arc portion is R, and the value range of R is 0.1mm≤R≤0.5mm. For example, the value of R can be 0.1mm, 0.2mm, 0.3mm, 0.4mm or 0.5mm, etc. By limiting the value of R within the above range, on the one hand, it is possible to avoid air suffocation in the cavity surrounded by the mold, the first groove bottom wall 1232, the first arc-shaped portion, and the first groove side wall 1231, thereby ensuring that the outer surface of the composite pole 100 after molding is smooth and has no concave defects; on the other hand, it is convenient for the material flow during riveting of the composite pole 100, so that after riveting, the first wall surface 1221 (that is, the first groove side wall 1231) of the annular flange 122 is coplanar with the first groove bottom wall 1232 (see Figure 5 ), and the surface is relatively smooth without any protrusions or depressions.

[0060] It should be noted that the value of R should not exceed 0.5mm, otherwise it will affect the flatness of the annular flange 122 and the battery cover after riveting, and unevenness is likely to occur at the intersection of the first groove bottom wall 1232 and the first groove side wall 1231 (i.e., the first arc portion). Of course, the value of R should not be too small, otherwise the intersection of the first groove bottom wall 1232 and the first groove side wall 1231 (i.e., the first arc portion) will have a sharp turn, and unevenness is likely to occur after the annular flange 122 and the battery cover are riveted, and the transition between the first wall surface 1221 of the annular flange 122 and the end surface of the second column 121 away from the plate body 111 is not flat.

[0061] Continue to see Figure 2 and Figure 3, a second groove 124 is provided at the center of the bottom wall 1232 of the first groove. Through the arrangement of the second groove 124, it is convenient to position the composite pole 100 and the bus bar by using a CCD detection mechanism during welding. The second groove 124 is in an inverted cone shape, and the diameter of the open end of the second groove 124 is larger than the diameter of the bottom of the second groove 124.

[0062] Exemplarily, the second groove 124 includes a second groove side wall 1241 and a second groove bottom wall 1242. There is an included angle k between the second groove side wall 1241 and the second groove bottom wall 1242, and the value range of k is 5° ≤ k ≤ 60°. For example, the value of k can be 5°, 10°, 20°, 30°, 40°, 50° or 60°, etc. By limiting the value of k within the above range, it can be ensured that the second groove 124 is easy to form during cold heading and has a high forming accuracy. Otherwise, when the value of k is too small, it is easy to cause air retention in the cavity surrounded by the mold, the second groove bottom wall 1242, the second arc portion, and the second groove side wall 1241, which may produce depression defects, and metal chips are also likely to remain in the second groove 124 during cold heading.

[0063] The diameter of the second groove bottom wall 1242 is φd, and the value range of φd is 0.5 mm ≤ φd ≤ 10 mm. For example, the value of φd can be 0.5 mm, 1.0 mm, 2.0 mm, 4.0 mm, 6.0 mm, 8.0 mm or 10.0 mm, etc. By limiting the value of φd within the above range, it is easy for the CCD detection mechanism to determine the position of the composite pole 100. Otherwise, when the value of φd is too small, the CCD detection mechanism is not easy to identify the second groove 124, and the positioning accuracy is poor. Of course, the value of φd should not be too large, otherwise it will affect the mechanical strength of the composite pole 100.

[0064] Furthermore, along the axial direction of the second column 121, the depth of the second groove 124 is e, and the value range of e is 0.5 mm ≤ e ≤ 5 mm. For example, the value of e can be 0.5 mm, 1.0 mm, 2.0 mm, 3.0 mm, 4.0 mm, 5.0 mm, etc. By limiting the value of e within the above range, it is easy for the CCD detection mechanism to determine the position of the composite pole 100. Otherwise, when the value of e is too small, the CCD detection mechanism is not easy to identify the second groove 124, and the positioning accuracy is poor. Of course, the value of e should not be too large, otherwise it will affect the mechanical strength of the composite pole 100.

[0065] Continue to refer to Figure 3, a second arc portion is provided for transition between a second groove side wall 1241 of the second groove 124 and a first groove bottom wall 1232 of the first groove 123. The radius of the second arc portion is R1, and the value range of R1 is 0.1 mm ≤ R1 ≤ 2 mm. For example, the value of R1 can be 0.1 mm, 0.3 mm, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, etc. By limiting the value of R1 within the above range, on the one hand, it can avoid air trapping in the cavity formed by the second groove bottom wall 1242, the second arc portion, and the second groove side wall 1241 of the mold, ensuring that the surfaces of the second groove bottom wall 1242 and the second groove side wall 1241 of the second groove 124 after molding are smooth, without depression defects, and not prone to generating metal residues; on the other hand, it is convenient for the material flow during the riveting of the composite pole column 100, and the second groove 124 is easy to form with high dimensional accuracy.

[0066] Continue to refer to Figure 2 , along the axial direction of the second column 121, the distance between the mating interface 1121 formed between the first column 112 and the second column 121 and the second groove bottom wall 1242 is c, and the value range of c is 0.5 mm ≤ c ≤ 10 mm. For example, the value of c can be 0.5 mm, 1.0 mm, 2.0 mm, 3.0 mm, 5.0 mm, 8.0 mm, 10.0 mm, etc. By limiting the value of c within the above range, it is to ensure that the connection strength between the copper part 110 and the aluminum part 120 in the composite pole column 100 is sufficient. Otherwise, when the value of c is too small, the distance between the second groove bottom wall 1242 of the second groove 124 and the mating interface 1121 is too small, affecting the bonding strength of the copper and aluminum at the mating interface 1121, resulting in the composite pole column 100 being prone to fracture at the mating interface 1121, and then causing the battery cover plate to fail. Of course, the value of c should not be too large either, otherwise the thickness of the battery cover plate is too large, occupying a large space, and the battery weight increases, which is not conducive to improving the energy density of the battery.

[0067] This embodiment also provides a battery, including a housing, a pole group, and a battery cover plate. Wherein, an opening is provided on one side of the housing, the pole group is installed into the housing through the opening, and the battery cover plate is connected to the opening of the housing. The pole group is encapsulated in a sealed space by the housing and the battery cover plate, and the above-mentioned composite pole column 100 is integrated on the battery cover plate. By adopting the above-mentioned composite pole column 100, the reliability of the battery is ensured to be relatively high, and the battery cover plate is not prone to failure.

[0068] Specifically, refer to Figures 6-9, in this embodiment, the battery cover plate includes a cover plate body 200, a first plastic part 400, and a second plastic part 500. There are two first plastic parts 400 and two second plastic parts 500. The two first plastic parts 400 are arranged on the side of the cover plate body 200 away from the electrode group, and the two second plastic parts 500 are arranged on the side of the cover plate body 200 close to the electrode group. The plate body 111 of the composite pole column 100 is electrically connected to the negative electrode tab of the electrode group. One end of the composite pole column 100 with an annular flange 122 is arranged through one of the second plastic parts 500, the cover plate body 200, and one of the first plastic parts 400. The annular flange 122 of the composite pole column 100 is riveted to the first plastic part 400. After riveting, the annular flange 122 is deformed, and the annular flange 122 presses the first plastic part 400 against the end face on the side of the cover plate body 200 away from the electrode group, and the plate body 111 presses the second plastic part 500 against the end face on the side of the cover plate body 200 close to the electrode group, thereby realizing the installation of the composite pole column 100 on the cover plate body 200. The first plastic part 400 and the second plastic part 500 are both made of insulating materials, and the composite pole column 100 is insulated from the cover plate body 200 through the first plastic part 400 and the second plastic part 500.

[0069] A pure aluminum pole column 300 is also integrated on the battery cover plate. The pure aluminum pole column 300 is electrically connected to the positive electrode tab of the electrode group. The appearance and dimensions of the pure aluminum pole column 300 and the composite pole column 100 are the same. The only difference is that the pure aluminum pole column 300 is formed by cold heading using a mold and aluminum sheet. One end of the pure aluminum pole column 300 with an annular flange 122 is arranged through the other second plastic part 500, the cover plate body 200, and the other first plastic part 400. The annular flange 122 of the pure aluminum pole column 300 is riveted to the other first plastic part 400. After riveting, the annular flange 122 is deformed, and the annular flange 122 of the pure aluminum pole column 300 presses the other first plastic part 400 against the end face on the side of the cover plate body 200 away from the electrode group, and the plate body 111 of the pure aluminum pole column 300 presses the other second plastic part 500 against the end face on the side of the cover plate body 200 close to the electrode group, thereby realizing the installation of the pure aluminum pole column 300 on the cover plate body 200. The pure aluminum pole column 300 is insulated from the cover plate body 200 through the first plastic part 400 and the second plastic part 500.

[0070] Furthermore, the battery cover plate further includes two sealing parts 600. One of the sealing parts 600 is sleeved on the composite pole column 100 and clamped between the composite pole column 100 and the cover plate body 200. The gap between the composite pole column 100 and the cover plate body 200 can be sealed through the sealing part 600. The other sealing part 600 is sleeved on the pure aluminum pole column 300 and clamped between the pure aluminum pole column 300 and the cover plate body 200. The gap between the pure aluminum pole column 300 and the cover plate body 200 can be sealed through the sealing part 600.

[0071] The parameters of the above composite pole 100 are verified in terms of appearance and push-pull force tested using the batteries in some specific implementation cases. For details, refer to Table 1.

[0072] Table 1

[0073]

[0074] Among them, for the appearance verification, mainly observe the appearance of the composite pole 100 after cold heading forming to see if there are any surface defects. In addition, measure the dimensions of each part of the composite pole 100 to determine whether its dimensions meet the standards. When both are okay, the appearance verification is qualified.

[0075] The push-pull force test is as follows: Fix the assembled battery, apply a thrust towards the pole group or a pull away from the pole group to the composite pole 100. If the thrust and / or pull exceeds 1000 N and the composite pole 100 is still fixed on the battery cover plate and the copper part 110 and the aluminum part 120 of the composite pole 100 do not separate at the mating interface 1121, then the push-pull force test is qualified.

[0076] From the above results, in Example 1, the value of S2 / S1 is close to the upper limit of its dimension range 0.15 ≤ S2 / S1 ≤ 0.48, and the remaining parameters are normally taken within their dimension ranges. The appearance of the composite pole 100 after cold heading forming is good, and the dimensions meet the standards, so the appearance verification passes. And the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite pole 100 is relatively high. After the composite pole 100 is assembled with the battery cover plate, it can resist a large external force, there is no risk of separation between the copper part 110 and the aluminum part 120, and the reliability is high. The push-pull force test passes and the battery is qualified.

[0077] In Example 2, the value of S2 / S1 is close to the lower limit of its dimension range 0.15 ≤ S2 / S1 ≤ 0.48, and the remaining parameters are normally taken within their dimension ranges. The appearance of the composite pole 100 after cold heading forming is good, and the dimensions meet the standards, so the appearance verification passes. And the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite pole 100 is relatively high. After the composite pole 100 is assembled with the battery cover plate, it can resist a large external force, there is no risk of separation between the copper part 110 and the aluminum part 120, and the reliability is high. The push-pull force test passes and the battery is qualified.

[0078] In Example 3, the value of h approaches the lower limit of its dimensional range of 0.2 mm ≤ h ≤ 5 mm, and the remaining parameters are normally taken within their dimensional ranges. The appearance of the composite terminal post 100 after cold heading forming is good, and its dimensions meet the standards, passing the appearance verification. Moreover, the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite terminal post 100 is high. After the composite terminal post 100 is assembled with the battery cover plate, it can resist a large external force, there is no risk of separation between the copper part 110 and the aluminum part 120, the reliability is high, the push-pull force test is passed, and the battery is qualified.

[0079] In Example 4, the value of B / A is at the upper limit of its dimensional range of 1.2 ≤ B / A ≤ 3, and the remaining parameters are normally taken within their dimensional ranges. The appearance of the composite terminal post 100 after cold heading forming is good, and its dimensions meet the standards, passing the appearance verification. Moreover, the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite terminal post 100 is high. After the composite terminal post 100 is assembled with the battery cover plate, it can resist a large external force, there is no risk of separation between the copper part 110 and the aluminum part 120, the reliability is high, the push-pull force test is passed, and the battery is qualified.

[0080] In Example 5, the value of B / A is at the lower limit of its dimensional range of 1.2 ≤ B / A ≤ 3, and the remaining parameters are normally taken within their dimensional ranges. The appearance of the composite terminal post 100 after cold heading forming is good, and its dimensions meet the standards, passing the appearance verification. Moreover, the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite terminal post 100 is high. After the composite terminal post 100 is assembled with the battery cover plate, it can resist a large external force, there is no risk of separation between the copper part 110 and the aluminum part 120, the reliability is high, the push-pull force test is passed, and the battery is qualified.

[0081] In Example 6, the value of c approaches the lower limit of its dimensional range of 0.5 mm ≤ c ≤ 10 mm, and the remaining parameters are normally taken within their dimensional ranges. The appearance of the composite terminal post 100 after cold heading forming is good, and its dimensions meet the standards, passing the appearance verification. Moreover, the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite terminal post 100 is high. After the composite terminal post 100 is assembled with the battery cover plate, it can resist a large external force, there is no risk of separation between the copper part 110 and the aluminum part 120, the reliability is high, the push-pull force test is passed, and the battery is qualified.

[0082] In Example 7, the value of S2 / S1 exceeds the upper limit of its dimensional range of 0.15 ≤ S2 / S1 ≤ 0.48, and the remaining parameters are normally taken within their dimensional ranges. The appearance of the composite terminal post 100 after cold heading forming is poor, its dimensions do not meet the standards, the appearance verification fails, and the battery is unqualified.

[0083] In Example 8, the value of h exceeded the lower limit of its dimensional range of 0.2 mm ≤ h ≤ 5 mm, and the remaining parameters were normally within their dimensional ranges. Although the appearance of the composite pole column 100 after cold heading forming was good and the dimensions met the standards, and the appearance verification passed. However, the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite pole column 100 was low. During the push-pull test, the copper part 110 and the aluminum part 120 of the composite pole column 100 separated, the reliability was low, it was prone to failure, the push-pull test failed, and the battery was unqualified.

[0084] In Example 9, the value of B / A exceeded the upper limit of its dimensional range of 1.2 ≤ B / A ≤ 3, and the remaining parameters were normally within their dimensional ranges. The appearance of the composite pole column 100 after cold heading forming was poor, the dimensions did not meet the standards, the appearance verification failed, and the battery was unqualified.

[0085] In Example 10, the value of B / A exceeded the lower limit of its dimensional range of 1.2 ≤ B / A ≤ 3, and the remaining parameters were normally within their dimensional ranges. The appearance of the composite pole column 100 after cold heading forming was poor, the dimensions did not meet the standards, the appearance verification failed, and the battery was unqualified.

[0086] In Example 11, the value of c exceeded the lower limit of its dimensional range of 0.5 mm ≤ c ≤ 10 mm, and the remaining parameters were normally within their dimensional ranges. The appearance of the composite pole column 100 after cold heading forming was good and the dimensions met the standards, and the appearance verification passed. However, the connection strength between the copper part 110 and the aluminum part 120 at the mating interface 1121 of the composite pole column 100 was low. During the push-pull test, the copper part 110 and the aluminum part 120 of the composite pole column 100 separated, the reliability was low, it was prone to failure, the push-pull test failed, and the battery was unqualified.

[0087] In summary, it can be seen that when the parameters S2 / S1, h, B / A, and c of the composite pole column 100 all meet their dimensional limits, it can ensure that the appearance of the composite pole column 100 after cold heading forming is good, the dimensional accuracy is high, meeting the product requirements, and the composite pole column 100 can withstand greater thrust and pull forces after being assembled with the battery cover plate, with high reliability and not prone to failure.

[0088] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limiting the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. A composite terminal post, characterized in that, The composite pole comprises: A copper material portion, the copper material portion comprising a plate body and a first column body connected to each other; An aluminum material portion, wherein the aluminum material portion includes a second column, the second column is connected to the first column, and a joint interface is formed between the second column and the first column; The volume of the aluminum material part is S1, and the volume of the copper material part is S2; S1 and S2 satisfy: 0.15≤S2 / S1≤0.48; An annular flange is provided on one side of the second column away from the plate body, the annular flange extends along the axial direction of the second column, and the annular flange has a first wall surface and a second wall surface along its radial direction, the first wall surface is close to the axis of the annular flange, and the second wall surface is flush with the peripheral side wall of the second column and the peripheral side wall of the first column; There is an angle α between the first wall surface and the second wall surface of the annular flange; The value range of α is 0.5°≤α≤3.0°.

2. The composite terminal post according to claim 1, wherein Along the axial direction of the second column, the distance between the interface and the end surface of the plate body close to the second column is h; The value range of h is 0.2mm≤h≤5mm; And / or, along the axial direction of the second column, the height of the plate is t, and the value range of t is 2mm≤t≤10mm; the dimensional tolerance of t is less than or equal to ±0.2mm.

3. The composite terminal post according to claim 1, wherein, Along the radial direction of the second cylinder, the thickness of the end of the annular flange away from the plate body is A; along the axial direction of the second cylinder, the height of the annular flange is B; Among them, A and B satisfy: 1.2≤B / A≤3; The value range of A is 0.5mm≤A≤3mm; The value range of B is 1mm≤B≤5mm.

4. The composite terminal post according to claim 1, wherein The inner side of the annular flange and the end surface of the second column facing away from the plate body form a first groove, the first wall surface is the first groove side wall of the first groove, the end surface of the second column facing away from the plate body is the first groove bottom wall, the first groove side wall and the first groove bottom wall are transitioned by a first arc portion, the radius of the first arc portion is R, and the value range of R is 0.1mm≤R≤0.5mm.

5. The composite terminal post according to claim 4, wherein A second groove is provided on the bottom wall of the first groove. The second groove is in an inverted cone shape. The diameter of the opening of the second groove is greater than the diameter of the groove bottom of the second groove.

6. The composite terminal post according to claim 5, characterized in that, Along the axial direction of the second cylinder, the depth of the second groove is e, and the value range of e is 0.5mm≤e≤5mm.

7. The composite terminal post according to claim 5, characterized in that, The second groove comprises a second groove side wall and a second groove bottom wall, and an angle k is formed between the second groove side wall and the second groove bottom wall; The value range of k is 5°≤k≤60°; and / or, the diameter of the bottom wall of the second groove is φd; The value range of φd is 0.5mm≤φd≤10mm.

8. The composite terminal post according to claim 7, wherein The second groove side wall and the first groove bottom wall are transitioned by a second arc-shaped portion, the radius of the second arc-shaped portion is R1, and the value range of R1 is 0.1mm≤R1≤2mm.

9. The composite terminal post according to claim 7, wherein Along the axial direction of the second cylinder, the distance between the mating interface formed between the first cylinder and the second cylinder and the bottom wall of the second groove is c, and the value range of c is 0.5mm ≤ c ≤ 10mm.

10. A battery, characterized in that, Comprising the composite pole column according to any one of claims 1-9.

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