Copper-aluminum composite pole and battery cover plate

Abstract

The invention relates to the technical field of batteries, in particular to a copper-aluminum composite pole and a battery cover plate, the copper-aluminum composite pole comprises a copper layer part and an aluminum layer part, the copper-aluminum composite pole comprises a pole body structure and a plate body structure, and the plate body structure is integrally connected with one end of the pole body structure in a first direction. Wherein the first part of the plate body structure and the first part of the column body structure are copper layer parts, the first part is the part, close to one end of the plate body structure, of the column body structure, and the second part of the column body structure is an aluminum layer part. The dimension of the first portion in the first direction is greater than or equal to 0.2 mm. According to the copper-aluminum composite pole and the battery cover plate provided by the invention, the combination of the copper layer part and the aluminum layer part of the copper-aluminum composite pole is stable, so that the structure of the copper-aluminum composite pole can be kept stable under the working conditions of vibration and bumping.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a copper-aluminum composite pole and a battery cover. Background Art

[0002] The negative pole of the current battery is usually designed as a copper-aluminum composite structure to ensure the welding performance of the negative pole. However, in the current copper-aluminum composite pole, the ratio between the copper layer and the aluminum layer of the negative pole is difficult to determine. If the ratio of the copper layer is too high, the manufacturing cost of the negative pole is greatly increased; if the ratio of the copper layer is insufficient, it is very easy to cause the connection stability between the copper layer and the aluminum layer of the negative pole to be poor. When the battery is vibrating and bumpy, the negative pole is very easy to break at the interface of the copper-aluminum composite. Summary of the invention

[0003] The purpose of the present application is to provide a copper-aluminum composite pole and a battery cover, so as to solve to a certain extent the technical problem that in the current copper-aluminum composite pole, the ratio between the copper layer part and the aluminum layer part of the negative pole is difficult to determine. If the ratio of the copper layer part is too high, the manufacturing cost of the negative pole is greatly increased; if the ratio of the copper layer part is insufficient, it is very easy to cause the connection stability between the copper layer part and the aluminum layer part of the negative pole to be poor, and the negative pole is very easy to break at the interface of the copper-aluminum composite when the battery is in a vibrating and bumpy working condition.

[0004] According to a first aspect of the present application, there is provided a copper-aluminum composite pole, the copper-aluminum composite pole comprising a copper layer portion and an aluminum layer portion, the copper-aluminum composite pole comprising a column structure and a plate structure, the plate structure being integrally connected to one end of the column structure in a first direction; The first part of the plate structure and the first part of the column structure are both the copper layer part, the first part is arranged at one end of the column structure close to the plate structure, and the second part of the column structure is the aluminum layer part; A dimension of the first portion in the first direction is greater than or equal to 0.2 mm.

[0005] Preferably, in the first direction, a dimension of the first portion in the first direction is less than or equal to 0.7 mm.

[0006] Preferably, the column structure is a cylinder, and the outer diameter of the column structure is greater than or equal to 5 mm.

[0007] Preferably, the outer diameter of the column structure is less than or equal to 15 mm.

[0008] Preferably, the copper-aluminum composite pole is a copper-aluminum friction welded part or a copper-aluminum rolled composite part.

[0009] Preferably, the operating temperature of the copper-aluminum composite pole is less than or equal to 350°C.

[0010] According to the second aspect of the present application, a battery cover is provided, comprising a cover body and a negative electrode column assembly, wherein the negative electrode column assembly comprises a negative electrode rivet block and the copper-aluminum composite electrode column described in any of the above embodiments, and thus has all the beneficial technical effects of the copper-aluminum composite electrode column, which will not be repeated here.

[0011] Specifically, the column structure of the copper-aluminum composite pole penetrates the cover plate body along the first direction and is connected to the negative electrode riveting block.

[0012] Preferably, it further comprises a positive electrode column assembly, the positive electrode column assembly comprising a positive electrode column and a positive electrode riveting block, a portion of the positive electrode column passes through the cover plate body along the first direction and is connected to the positive electrode riveting block; The positive electrode column, the positive electrode riveted block and the negative electrode riveted block are all aluminum parts.

[0013] Preferably, the battery cover plate further comprises a cover plate insulating member, and the cover plate insulating member covers a side of the battery cover plate which is away from the negative electrode riveting block; A portion of the cover plate insulation extends between the plate structure and the cover plate body.

[0014] Preferably, the negative electrode column assembly further comprises: A negative electrode insulating member, disposed between the negative electrode riveting block and the cover plate body; The negative electrode sealing ring is sleeved on the outer side of the column structure, and the two ends of the negative electrode sealing ring in the first direction are respectively connected to the negative electrode insulating member and the cover plate insulating member.

[0015] Compared with the prior art, the beneficial effects of this application are: The copper-aluminum composite pole provided by the present application extends the copper layer portion in the copper-aluminum composite pole from the plate structure to the column structure, and the copper layer portion extends on the column structure, that is, the size of the first part in the first direction (i.e. Figure 2 The h value shown is greater than or equal to 0.2 mm, and the copper layer part and the aluminum layer part of the copper-aluminum composite pole are stably combined, which can ensure that the copper-aluminum composite pole maintains structural stability under vibration and bumpy working conditions.

[0016] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A schematic diagram of the axonometric structure of a copper-aluminum composite pole provided in an embodiment of the present application; Figure 2 A schematic diagram of the cross-sectional structure of a copper-aluminum composite pole provided in an embodiment of the present application; Figure 3 A schematic diagram of the isometric structure of a battery cover provided in an embodiment of the present application; Figure 4 A schematic diagram of the front structure of a battery cover provided in an embodiment of the present application; Figure 5 for Figure 4 A schematic diagram of the cross-section structure of the copper-aluminum composite pole obtained by cutting along the AA direction; Figure 6 for Figure 5 The enlarged structural schematic diagram of the copper-aluminum composite pole at position B is provided; Figure 7 A schematic diagram of the isometric structure of a battery cover provided in another embodiment of the present application; Figure 8 A schematic diagram of a cross-sectional structure of a battery cover provided in yet another embodiment of the present application; Fig. 9 A schematic diagram of the axonometric structure of a copper-aluminum composite pole provided in yet another embodiment of the present application; Fig.10 This is the curve of IMC layer thickness changing with annealing temperature.

[0019] Reference numerals: 1-negative pole column assembly; 11-copper-aluminum composite pole; 111-column structure; 1111-first part; 1112-second part; 112-plate structure; 12-negative pole riveting block; 13-negative pole insulator; 14-negative pole sealing ring; 2-positive pole column assembly; 21-positive pole column; 211-column part; 212-plate part; 22-positive pole riveting block; 23-positive pole insulator; 24-positive pole sealing ring; 3-cover plate body; 31-cover plate insulator; 4-explosion-proof valve; 5-liquid injection hole.

[0020] F1-first direction; F2-second direction; F3-third direction. DETAILED DESCRIPTION

[0021] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0022] The components of the embodiments of the present application generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents the selected embodiments of the present application.

[0023] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0024] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application 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 cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0025] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0026] Refer to the following Figures 1 to 6 The copper-aluminum composite pole 11 and the battery cover plate according to some embodiments of the present application are described.

[0027] See also Figures 1 to 6As shown, an embodiment of the first aspect of the present application provides a copper-aluminum composite pole 11, which includes a copper layer portion and an aluminum layer portion. The copper-aluminum composite pole 11 includes a column structure 111 and a plate structure 112, and the plate structure 112 is integrally connected to one end of the column structure 111 in the first direction F1. Among them, the plate structure 112 and the first part 1111 of the column structure 111 are both copper layer portions, and the first part 1111 is arranged at one end of the column structure 111 close to the plate structure 112, and the second part 1112 of the column structure 111 is an aluminum layer portion. The size of the first part 1111 in the first direction F1 (i.e. Figure 2 The h value shown) is greater than or equal to 0.2 mm.

[0028] When other structural dimensions are the same, the applicant selects copper-aluminum composite poles 11 with different data of the dimensions of the first part 1111 in the first direction F1, and performs pull-out test and side-pushing test on the copper-aluminum composite poles 11 respectively. Table 1 shows the dimensional data and corresponding test results of the pull-out test and side-pushing test of the copper-aluminum composite poles 11.

[0029] It should be noted that the pull-out test of the copper-aluminum composite pole 11 can be understood as using a tensile testing machine (e.g., a universal tensile testing machine) to act on both ends of the copper-aluminum composite pole 11 in the first direction F1, pulling the copper-aluminum composite pole 11 along the first direction F1, and recording the tensile force value when the copper-aluminum composite pole 11 is pulled off (i.e., the pull-out strength value of the copper-aluminum composite pole 11 shown in Table 1), wherein the pull-out strength of the copper-aluminum composite pole 11 is between 75-95Mpa, and the tensile strength of the copper-aluminum composite pole 11 is considered qualified. And observe the pull-off position of the copper-aluminum composite pole 11.

[0030] In addition, the above-mentioned side push test of the copper-aluminum composite pole 11 can be understood as applying side push forces perpendicular to the first direction F1 and in opposite directions and equal in value to each other at both ends of the copper-aluminum composite pole 11 in the first direction F1 to observe the fracture position of the copper-aluminum composite pole 11 under the action of shear stress.

[0031] Table 1:

[0032] It can be seen from the data shown in Table 1 that, under the condition that the outer diameter d of the column structure 111 is the same, when the dimension h of the first part 1111 in the first direction F1 is less than 0.2 mm, no matter whether d=5 mm, d=8 mm, d=12 mm or d=15 mm, the fracture position of the pull-out test and the side-thrust test is the copper-aluminum bonding surface. When the dimension h of the first part 1111 in the first direction F1 is greater than or equal to 0.2 mm, no matter whether d=5 mm, d=8 mm, d=12 mm or d=15 mm, the fracture position of the pull-out test and the side-thrust test is not at the copper-aluminum bonding surface. In other words, the copper layer portion in the copper-aluminum composite pole 11 is extended from the plate structure 112 to the column structure 111, and the copper layer portion is extended on the column structure 111 by a length, that is, the dimension of the first part 1111 in the first direction F1 (that is, Figure 2 The h value shown is greater than or equal to 0.2 mm, and the copper layer part and the aluminum layer part of the copper-aluminum composite pole 11 are stably combined, which can ensure that the copper-aluminum composite pole 11 maintains structural stability under vibration and bumpy working conditions.

[0033] Preferably, in the first direction F1, the dimension h of the first part 1111 in the first direction F1 is less than or equal to 0.7 mm. As shown in Table 1, on the one hand, when 0.2 mm ≤ h of the copper-aluminum composite pole 11, both the copper layer portion and the aluminum layer portion of the copper-aluminum composite pole 11 can be stably combined; on the other hand, making h ≤ 0.7 mm of the copper-aluminum composite pole 11 can effectively take into account the manufacturing cost of the copper-aluminum composite pole 11.

[0034] like Figures 1 to 6 As shown, F1 shown in the figure may be an example of the first direction F1. For the convenience of description, two directions perpendicular to each other on a plane perpendicular to the first direction F1 are defined as a second direction F2 and a third direction F3, F2 shown in the figure may be an example of the second direction F2, and F3 shown in the figure may be an example of the third direction F3.

[0035] Preferably, if Figure 1 As shown, the column structure 111 may be a cylinder to facilitate the processing and manufacturing of the column structure 111 .

[0036] Preferably, the outer diameter of the column structure 111 (i.e. Figure 2 Referring to Table 2, when the outer diameter d of the column structure 111 is less than 5 mm, no matter the h value is greater than 0.2 mm or greater than 0.7 mm, the tensile strength of the copper-aluminum composite pole 11 is unqualified, and the bonding stability of the copper layer and the aluminum layer is poor.

[0037] Table 2:

[0038] Preferably, the outer diameter of the column structure 111 (ie, Figure 2 The d value shown) can be less than or equal to 15 mm to accommodate most battery cover structures.

[0039] Optionally, the copper-aluminum composite pole 11 may be a copper-aluminum friction welded part.

[0040] Optionally, the copper-aluminum composite pole 11 may be a copper-aluminum rolled composite part.

[0041] Preferably, the operating temperature of the copper-aluminum composite pole 11 can be less than or equal to 350° C. Fig.10 The graph shows the variation curve of the IMC (i.e., intermetallic compound) layer thickness with the annealing temperature. When the operating temperature of the copper-aluminum composite pole 11 can be less than or equal to 350°C, the thickness of the IMC generated by the phase change at the copper-aluminum bonding surface of the copper-aluminum composite pole 11 under high temperature conditions can be effectively reduced, thereby preventing the IMC from affecting the bonding stability of the copper layer and the aluminum layer.

[0042] It should be noted that the above column structure is not limited to Figure 1 The cylindrical structure shown in the figure can also be other column structures as long as the connection strength between the copper layer and the aluminum layer can be guaranteed, for example, Fig. 9 The elliptical column structure shown, or other polygonal columns, special-shaped columns, etc.

[0043] See also Figures 3 to 6 The embodiment of the second aspect of the present application also provides a battery cover, including a cover body 3 and a negative electrode column assembly 1, wherein the negative electrode column assembly 1 includes a negative electrode rivet block 12 and the copper-aluminum composite electrode 11 described in any of the above embodiments, and thus has all the beneficial technical effects of the copper-aluminum composite electrode 11, which will not be repeated here.

[0044] Specifically, Figures 3 to 6 As shown, the column structure 111 of the copper-aluminum composite pole 11 passes through the cover body 3 along the first direction F1 and is connected to the negative electrode riveting block 12 .

[0045] Preferably, if Figures 3 to 6 As shown, the battery cover may further include a cover insulating member 31, which covers the side of the battery cover facing away from the negative electrode rivet block 12 to achieve insulation between the cover body and the inside of the battery. Figure 6 As shown, part of the cover plate insulating member 31 extends between the plate structure 112 and the cover plate body 3 , so as to achieve insulation between the plate structure 112 and the cover plate body 3 .

[0046] Preferably, if Figures 3 to 6As shown, the negative electrode column assembly 1 may further include a negative electrode insulating member 13 , which may be disposed between the negative electrode rivet block 12 and the cover plate body 3 to achieve insulation between the negative electrode rivet block and the cover plate body 3 .

[0047] Preferably, if Figures 3 to 6 As shown, the negative electrode column assembly 1 may further include a negative electrode sealing ring 14, which may be sleeved on the outside of the column structure 111 to prevent the portion of the column structure 111 that penetrates the cover body 3 from contacting the cover body 3. Both ends of the negative electrode sealing ring 14 in the first direction F1 are respectively connected to the negative electrode insulating member 13 and the cover plate insulating member 31, so that the negative electrode column assembly 1 can be completely insulated from the cover body 3.

[0048] Optionally, the negative electrode riveted block 12 can be riveted and fixed to the cover plate body 3 via a plurality of copper-aluminum composite poles 11 to improve the riveting stability and flatness of the negative electrode riveted block 12. Figure 7 and Figure 8 As shown, the figure shows an example in which the negative electrode riveted block 12 is riveted and fixed to the cover plate body 3 via two copper-aluminum composite poles 11 , but it is not limited thereto, and the number of copper-aluminum composite poles 11 can be adaptively adjusted according to the size of the negative electrode riveted block 12 .

[0049] Alternatively, if Figure 7 and Figure 8 As shown, the figure shows an example in which the battery cover only includes a negative column assembly. In other words, not shown in the figure, the battery cover can be suitable for batteries in which the negative column assembly and the positive column assembly are respectively arranged at both ends of the battery in the first direction, such as blade batteries.

[0050] However, it is not limited thereto, and optionally, Figures 3 to 5 As shown, the battery cover plate may further include a positive electrode column assembly 2. Correspondingly, as Figure 5 As shown, the positive electrode column assembly 2 may also include a positive electrode column 21 and a positive electrode riveting block 22 . A portion of the positive electrode column 21 penetrates the cover body 3 along the first direction F1 and is connected to the positive electrode riveting block 22 .

[0051] Similarly, if Figure 5 As shown, the above-mentioned positive electrode column 21 may also include a plate portion 212 and a column portion 211 fixedly connected to each other, wherein the column portion 211 penetrates the cover body 3 along the first direction F1 and is connected to the positive electrode riveting block 22, and the plate portion 212 is clamped on the side of the cover body 3 away from the positive electrode riveting block 22.

[0052] Correspondingly, if Figure 5 As shown, part of the cover plate insulating member 31 may also extend between the plate portion 212 and the cover plate body 3 , so as to achieve insulation between the plate portion 212 and the cover plate body 3 .

[0053] Similarly, if Figure 5 As shown, the positive electrode column assembly 2 may also include a positive electrode insulator 23 and a positive electrode sealing ring 24. The positive electrode insulator 23 may be disposed between the positive electrode rivet block 22 and the cover body 3 to achieve insulation between the positive electrode rivet block and the cover body 3. The positive electrode sealing ring 24 may be sleeved on the outside of the column portion 211 to prevent the portion of the column portion 211 that passes through the cover body 3 from contacting the cover body 3. The two ends of the positive electrode sealing ring 24 in the first direction F1 are respectively connected to the positive electrode insulator 23 and the cover insulator 31, so that the positive electrode column assembly 2 can be completely insulated from the cover body 3.

[0054] Preferably, the positive electrode column 21 , the positive electrode riveted block 22 and the negative electrode riveted block 12 are all made of aluminum.

[0055] Alternatively, if Figures 3 to 5 As shown, the positive electrode column assembly 2 and the negative electrode column assembly 1 are spaced apart along the second direction F2 to prevent the positive electrode column assembly 2 and the negative electrode column assembly 1 from interfering with each other in electrical connection.

[0056] Preferably, if Figures 3 to 5 As shown, the battery cover plate may further include an explosion-proof valve 4 to ensure the safety of the battery. The explosion-proof valve 4 may be disposed at the portion of the cover plate body 3 between the positive electrode column assembly 2 and the negative electrode column assembly 1, so as to utilize the space between the positive electrode column assembly 2 and the negative electrode column assembly 1 of the cover plate body 3 to improve the space utilization of the battery cover plate.

[0057] Preferably, if Figures 3 to 5 As shown, the battery cover may further include an injection hole 5 to facilitate battery injection. The injection hole 5 may also be disposed in the portion of the cover body 3 between the positive electrode column assembly 2 and the negative electrode column assembly 1, so as to utilize the space between the positive electrode column assembly 2 and the negative electrode column assembly 1 of the cover body 3 to improve the space utilization of the battery cover.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A copper-aluminum composite pole, characterized in that: The copper-aluminum composite pole comprises a copper layer portion and an aluminum layer portion, the copper-aluminum composite pole comprises a column structure and a plate structure, and the plate structure is integrally connected to one end of the column structure in the first direction; The first part of the plate structure and the first part of the column structure are both the copper layer part, the first part is arranged at one end of the column structure close to the plate structure, and the second part of the column structure is the aluminum layer part; The dimension of the first portion in the first direction is greater than or equal to 0.2 mm.

2. The copper-aluminum composite pole according to claim 1, characterized in that: In the first direction, a dimension of the first portion in the first direction is less than or equal to 0.7 mm.

3. The copper-aluminum composite pole according to claim 2, characterized in that: The column structure is a cylinder, and the outer diameter of the column structure is greater than or equal to 5 mm.

4. The copper-aluminum composite pole according to claim 3, characterized in that: The outer diameter of the column structure is less than or equal to 15 mm.

5. The copper-aluminum composite pole according to any one of claims 1 to 4, characterized in that: The copper-aluminum composite pole is a copper-aluminum friction welded part or a copper-aluminum rolled composite part.

6. The copper-aluminum composite pole according to any one of claims 1 to 4, characterized in that: The operating temperature of the copper-aluminum composite pole is less than or equal to 350°C.

7. A battery cover, characterized in that: It comprises a cover plate body and a negative pole column assembly, wherein the negative pole column assembly comprises a negative pole riveting block and a copper-aluminum composite pole as claimed in any one of claims 1 to 6, The column structure of the copper-aluminum composite pole penetrates the cover plate body along the first direction and is connected to the negative electrode riveting block.

8. The battery cover according to claim 7, characterized in that: Also included is a positive electrode column assembly, the positive electrode column assembly includes a positive electrode column and a positive electrode riveting block, a portion of the positive electrode column passes through the cover plate body along the first direction and is connected to the positive electrode riveting block; The positive pole column, the positive pole riveting block and the negative pole riveting block are all aluminum parts.

9. The battery cover according to claim 7, characterized in that: The battery cover plate further comprises a cover plate insulating member, wherein the cover plate insulating member covers a side of the battery cover plate facing away from the negative electrode riveting block; A portion of the cover plate insulation extends between the plate structure and the cover plate body.

10. The battery cover according to claim 9, characterized in that: The negative electrode column assembly also includes: A negative electrode insulating member, disposed between the negative electrode riveting block and the cover plate body; The negative electrode sealing ring is sleeved on the outer side of the column structure, and the two ends of the negative electrode sealing ring in the first direction are respectively connected to the negative electrode insulating member and the cover plate insulating member.

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