Top cover assembly

Abstract

The utility model relates to the technical field of power battery top covers, and provides a top cover assembly which comprises a cover plate and a pole, the pole comprises a lower pole plate and an upper pole plate, and the lower pole plate penetrates through the cover plate and is fixedly connected with the cover plate in an insulating and sealing manner; and the upper pole plate is fixedly arranged on the lower pole plate. According to the utility model, the lower pole plate and the upper pole plate are arranged, the lower pole plate is fixedly connected with the cover plate, and the upper pole plate is fixedly connected with the lower pole plate, so that when the lower pole plate and the upper pole plate are made of different materials and are loosened due to the influence of environmental factors, the lower pole plate and the upper pole plate are fixed; and the fixing firmness degree and the sealing insulation performance of the lower pole plate and the cover plate cannot be influenced, so that the fixing firmness degree of the top cover assembly is improved, and the overall performance of the battery is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of power battery top covers, in particular to a top cover assembly. Background Art

[0002] The top cover assembly is an important component of the power battery. When assembling the battery top cover, ultrasonic welding is generally used to connect the pole tab and the adapter plate, and then the adapter plate is connected to the pole post of the cover plate by laser welding, so as to achieve conduction between the battery cell and the pole post. However, since the positive pole tab is usually aluminum foil and the negative pole tab is usually copper foil, in order to ensure the consistency of the welding material, the negative pole post needs to be made into a copper-aluminum composite pole post, and then the negative pole post is connected to the copper negative pole adapter plate and the negative pole tab by welding.

[0003] The utility model with patent publication number CN213989133U discloses a pole assembly, a top cover structure and a power battery, wherein the pole assembly includes an upper pole and a lower pole, the top surface of the upper pole is provided with a clearance hole, the clearance hole is not connected with the bottom surface of the upper pole, an upper boss is provided in the clearance hole, the interior of the upper boss is a hollow structure connected with the bottom surface of the upper pole, the top surface of the lower pole is provided with a lower boss, the interior of the lower boss is a hollow structure connected with the bottom surface of the lower pole, the lower boss is matched and arranged inside the upper boss, and under the action of external force, the side walls of the upper boss and the lower boss expand outward to form an inverted cone matching structure with a large upper part and a small lower part. The pole assembly does not need to be subjected to copper-aluminum friction welding or composite process, and the upper pole and the lower pole can be connected by self-piercing riveting process when the top cover is assembled, which reduces the steps of the top cover manufacturing process, reduces the use of pole materials, and is conducive to reducing the weight of the top cover and the overall production cost.

[0004] The above technical solution sets up an upper pole and a lower pole that are connected to each other. When the pole is a negative pole, the upper pole and the lower pole can be set to aluminum and copper respectively, thereby eliminating the copper-aluminum friction welding process of the pole. However, the fixed connection between the pole and the cover plate is achieved by using the upper pole and the lower pole to simultaneously support the cover plate. When the upper pole and the lower pole of different materials are affected by environmental factors such as temperature, they will loosen to a certain extent, causing the pole and the cover plate to loosen, causing the electrolyte inside the battery to leak out, thereby affecting the overall performance of the battery. Utility Model Content

[0005] In view of this, the utility model proposes a top cover assembly, which can improve the fixing firmness of the pole and the cover plate and ensure the overall performance of the battery.

[0006] The technical solution of the utility model is implemented as follows: The utility model provides a top cover assembly, including a cover plate and a pole, wherein the pole includes a lower pole plate and an upper pole plate, wherein:

[0007] The lower terminal plate penetrates through the cover plate and is fixedly and insulatingly sealed to it;

[0008] The upper terminal plate is fixedly arranged on the lower terminal plate.

[0009] Based on the above technical solutions, preferably, it further includes a connecting piece, and the connecting piece is abutted and arranged on one side of the cover plate;

[0010] The lower terminal plate includes a fixed boss and a curled edge, wherein,

[0011] The fixed boss penetrates through the cover plate and is fixedly connected to the connecting piece;

[0012] The curled edge is integrally formed on the fixed boss and abuts against the side of the cover plate away from the connecting piece.

[0013] More preferably, the lower terminal plate further includes a connecting boss, and the connecting boss is integrally formed on the side of the fixed boss away from the connecting piece;

[0014] A connecting hole is formed in the upper terminal plate, and the connecting boss is fixedly arranged in the connecting hole.

[0015] More preferably, the inner diameter of the connecting hole gradually increases in the direction from the connecting piece to the upper terminal plate, the connecting boss abuts against the inner wall of the connecting hole, and the upper terminal plate abuts against the curled edge.

[0016] More preferably, the upper terminal plate includes a welding part and an abutting part, wherein,

[0017] The welding part is fixedly connected to the connecting boss;

[0018] The abutting part is integrally formed on the welding part and abuts against the curled edge;

[0019] The thickness of the welding part is greater than the thickness of the abutting part, and the side of the abutting part away from the connecting piece is flush with the side of the welding part away from the connecting piece.

[0020] More preferably, it further includes a sealing ring, and the sealing ring is abutted and arranged between the cover plate and the connecting piece and between the cover plate and the lower terminal plate.

[0021] More preferably, it further includes a plastic ring, and the plastic ring is abutted and arranged between the cover plate and the lower terminal plate.

[0022] Based on the above technical solutions, preferably, there are two pole posts, the material of one of the lower pole post plates is copper, and the materials of the other lower pole post plate and the two upper pole post plates are both aluminum.

[0023] More preferably, both the fixing boss and the connecting boss are hollow structures and are continuously arranged.

[0024] Based on the above technical solutions, preferably, it further includes an explosion-proof valve, and the explosion-proof valve is fixedly arranged on the cover plate.

[0025] A top cover assembly of the present utility model has the following beneficial effects compared with the prior art:

[0026] (1) By providing the lower pole post plate and the upper pole post plate, fixedly connecting the lower pole post plate to the cover plate and fixedly connecting the upper pole post plate to the lower pole post plate. When the lower pole post plate and the upper pole post plate are made of different materials and loosen due to environmental factors, it will not affect the fixing firmness between the lower pole post plate and the cover plate and the sealing and insulation performance, thereby improving the fixing firmness of the present top cover assembly and ensuring the overall performance of the battery;

[0027] (2) By setting the connection hole to be conical, the fixing firmness between the upper pole post plate and the lower pole post plate can be improved by using the abutting effect of the connecting boss;

[0028] (3) By making the thickness of the welding part greater than the thickness of the abutting part, the welding effect between the upper pole post plate and the bus bar can be ensured. By making the side of the welding part and the abutting part away from the adapter plate flush, the welding part can extend into the interior of the fixing boss, thereby reducing the occupied space of the pole post and improving the space utilization rate of the battery. Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 It is a cross-sectional view of the pole post in a top cover assembly of the present utility model;

[0031] Figure 2 For Figure 1 The enlarged view of A in

[0032] Figure 3 It is an exploded view of the pole post in a top cover assembly of the present utility model;

[0033] Figure 4 A perspective view of a top cover assembly of the present utility model.

[0034] Wherein: 1. Cover plate; 2. Terminal post; 21. Lower terminal post plate; 211. Fixed boss; 212. Hem; 213. Connecting boss; 22. Upper terminal post plate; 221. Welding part; 222. Supporting part; 201. Connecting hole; 3. Adapter plate; 4. Sealing ring; 5. Plastic ring; 6. Explosion-proof valve. Specific embodiments

[0035] Next, in combination with the specific embodiments of the present utility model, the technical solutions in the present utility model will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0036] As Figures 1-4 shown, a top cover assembly of the present utility model includes a cover plate 1, a terminal post 2, an adapter plate 3, a sealing ring 4, a plastic ring 5 and an explosion-proof valve 6.

[0037] The cover plate 1 is used to seal the battery housing.

[0038] The terminal post 2 is used for electrically connecting with the battery cell. The terminal post 2 includes a lower terminal post plate 21 and an upper terminal post plate 22. As Figure 1 shown, the lower terminal post plate 21 penetrates through the cover plate 1 and is hermetically connected with insulation, which can avoid the leakage of electrolyte and also prevent the terminal post 2 from making electrical connection with the housing and the cover plate 1. The lower terminal post plate 21 is fixedly arranged on the cover plate 1, and the upper terminal post plate 22 is fixedly arranged on the lower terminal post plate 21. When the terminal post 2 is used as the negative terminal post 2, in order to ensure the consistency of the welding material between the terminal post 2 and the battery cell tab, the lower terminal post plate 21 and the upper terminal post plate 22 are made of different materials. When the two different materials are affected by environmental factors, different physical or chemical changes will occur. For example, the thermal expansion coefficients of the two materials are different. At the same temperature, the two materials will bend to different degrees, resulting in loosening of the lower terminal post plate 21 and the upper terminal post plate 22 of the two materials. Since the lower terminal post plate 21 is directly fixed to the cover plate 1 and does not cooperate with the upper terminal post plate 22 to fix to the cover plate 1, therefore, the loosening of the lower terminal post plate 21 and the upper terminal post plate 22 will not affect the fixing performance of the lower terminal post plate 21 to the cover plate 1, thus improving the fixing firmness of the terminal post 2 to the cover plate 1 and ensuring the quality of the top cover assembly.

[0039] There are two pole columns 2, one used as the positive pole and the other as the negative pole. To ensure the consistency of the welding material, the negative pole column 2 is usually made of copper and aluminum materials, and the positive pole column 2 is all made of aluminum materials. Therefore, one of the lower pole column plates 21 is made of copper, and the other lower pole column plate 21 and the two upper pole column plates 22 are all made of aluminum.

[0040] The adapter plate 3 is used to connect the battery cell and the pole column 2. The adapter plate 3 is abutted and arranged on one side of the cover plate 1 and is located inside the battery case.

[0041] As Figure 1 and Figure 2 shown, the lower pole column plate 21 includes a fixing boss 211 and a curled edge 212. The fixing boss 211 penetrates through the cover plate 1 and is fixedly connected to the adapter plate 3; the curled edge 212 is integrally formed on the fixing boss 211 and abuts against the side of the cover plate 1 away from the adapter plate 3. Thus, by the abutment of the adapter plate 3 and the curled edge 212 on both sides of the cover plate 1, the fixing boss 211 is fixed to the cover plate 1.

[0042] As Figure 1 and Figure 3 shown, the lower pole column plate 21 further includes a connecting boss 213. The connecting boss 213 is integrally formed on the side of the fixing boss 211 away from the adapter plate 3; a connecting hole 201 is formed in the upper pole column plate 22, and the connecting boss 213 is fixedly arranged in the connecting hole 201. By the connection and cooperation of the connecting boss 213 and the connecting hole 201, the fixed connection between the upper pole column plate 22 and the lower pole column plate 21 is realized.

[0043] To improve the connection firmness between the upper pole column plate 22 and the lower pole column plate 21, it is preferred that the inner diameter of the connecting hole 201 gradually increases in the direction from the adapter plate 3 to the upper pole column plate 22, that is, the connecting hole 201 is in the shape of a tapered hole. After the connecting boss 213 passes through the connecting hole 201, the connecting boss 213 is pressed and deformed by using the riveting technology, so that the connecting boss 213 abuts against the inner wall of the connecting hole 201, avoiding the separation between the upper pole column plate 22 and the lower pole column plate 21. And to prevent the upper pole column plate 22 from sliding towards the cover plate 1, it is preferred that the upper pole column plate 22 abuts against the curled edge 212, that is, the curled edge 212 and the connecting boss 213 abut against both sides of the upper pole column plate 22 to strengthen the connection firmness between the upper pole column plate 22 and the lower pole column plate 21.

[0044] Specifically, the connecting hole 201 is set as a through hole, and in the initial state, the connecting boss 213 is in the shape of a cylindrical structure. After the connecting boss 213 passes through the connecting hole 201, the connecting boss 213 is press-riveted to make the connecting boss 213 fit the inner wall of the connecting hole 201, so as to play a positioning role.

[0045] As Figure 1As shown, the upper terminal plate 22 includes a welding portion 221 and a abutting portion 222. Among them, the welding portion 221 is fixedly connected to the connecting boss 213; the abutting portion 222 is integrally formed on the welding portion 221 and abuts against the curled edge 212; the connecting hole 201 is preferably arranged at the middle position of the welding portion 221. By using the cooperation between it and the connecting boss 213 and the cooperation between the abutting portion 222 and the curled edge 212, the fixation of the upper terminal plate 22 and the lower terminal plate 21 is realized.

[0046] The upper terminal plate 22 is located on the side of the cover plate 1 away from the battery case. The welding portion 221 is used for welding conduction with the bus bar. In order to avoid problems during the welding of the upper terminal plate 22 and the bus bar, it is preferred that the thickness of the welding portion 221 is greater than the thickness of the abutting portion 222, that is, the welding portion 221 is thickened. Of course, it is preferred that the welding portion 221 is a plate-like structure with a uniform thickness.

[0047] At the same time, the side of the abutting portion 222 away from the adapter piece 3 is flush with the side of the welding portion 221 away from the adapter piece 3. Also, since the side of the abutting portion 222 close to the adapter piece 3 abuts against the curled edge 212, therefore, the welding portion 221 with a larger thickness needs to extend into the fixing boss 211, reducing the occupied space of the terminal 2, thereby improving the space utilization rate of the battery.

[0048] As Figure 3 shown, both the fixing boss 211 and the connecting boss 213 are hollow structures and are continuously arranged, that is, the fixing boss 211, the curled edge 212 and the connecting boss 213 can be formed by stamping a whole sheet of plate. The shape of the upper terminal plate 22 is uniform and can also be made by stamping or cutting, thereby further improving the processing efficiency of the terminal 2.

[0049] The sealing ring 4 is used for sealing the top cover assembly. The sealing ring 4 is abutted and arranged between the cover plate 1 and the adapter piece 3 and between the cover plate 1 and the lower terminal plate 21.

[0050] The plastic ring 5 is used for insulating and sealing the cover plate 1 and the terminal 2. The plastic ring 5 is abutted and arranged between the cover plate 1 and the lower terminal plate 21. As Figure 2 shown, the plastic ring 5 and the sealing ring 4 are respectively located on both sides of the cover plate 1 and both penetrate through the cover plate 1 to achieve butt joint, so as to comprehensively enclose the lower terminal plate 21, improving the sealing and insulating performance of the lower terminal plate 21 and the cover plate 1. At the same time, it is preferred that the plastic ring 5 wraps the connection gap between the upper terminal plate 22 and the lower terminal plate 21 to prevent the upper terminal plate 22 from being separated from the lower terminal plate 21 by external force.

[0051] The explosion-proof valve 6 is used to discharge the gas inside the battery when the battery is over-pressured or the temperature is too high. The explosion-proof valve 6 is fixedly arranged on the cover plate 1.

[0052] The working principle of a top cover assembly of the present utility model is as follows:

[0053] As Figure 1 and Figure 2 shown, by using the abutting fit between the connecting boss 213 and the conical connecting hole 201, the upper pole plate 22 can be abutted and fixed on the lower pole plate 21. The fixing bosses 211 are respectively connected to the curled edge 212 and the adapter plate 3. By using the abutting of the curled edge 212 and the adapter plate 3 on both sides of the cover plate 1, the lower pole plate 21 can be separately fixed on the cover plate 1. When the pole 2 is used as the negative electrode, the upper pole plate 22 is made of aluminum and the lower pole plate 21 is made of copper. If the upper pole plate 22 and the lower pole plate 21 are loosened due to environmental factors, it will not affect the fixing, sealing and insulating connection between the lower pole plate 21 and the cover plate 1, thus not affecting the performance of the top cover assembly and ensuring the quality of the battery.

[0054] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A top cover assembly, characterized in that: It includes a cover plate (1) and a terminal post (2). The terminal post (2) includes a lower terminal post plate (21) and an upper terminal post plate (22). Among them, the lower terminal post plate (21) penetrates through the cover plate (1) and is fixedly and insulatingly sealed to it; the upper terminal post plate (22) is fixedly arranged on the lower terminal post plate (21).

2. The top cover assembly according to claim 1, wherein: It further includes a connecting piece (3). The connecting piece (3) is abutted and arranged on one side of the cover plate (1); the lower terminal post plate (21) includes a fixing boss (211) and a curled edge (212). Among them, the fixing boss (211) penetrates through the cover plate (1) and is fixedly connected to the connecting piece (3); the curled edge (212) is integrally formed on the fixing boss (211) and abuts against the side of the cover plate (1) away from the connecting piece (3).

3. The top cover assembly according to claim 2, characterized in that: The lower terminal post plate (21) further includes a connecting boss (213). The connecting boss (213) is integrally formed on the side of the fixing boss (211) away from the connecting piece (3); a connecting hole (201) is formed in the upper terminal post plate (22), and the connecting boss (213) is fixedly arranged in the connecting hole (201).

4. The top cover assembly according to claim 3, characterized in that: The inner diameter of the connecting hole (201) gradually increases in the direction from the connecting piece (3) to the upper terminal post plate (22). The connecting boss (213) abuts against the inner wall of the connecting hole (201), and the upper terminal post plate (22) abuts against the curled edge (212).

5. The top cover assembly according to claim 4, wherein: The upper terminal post plate (22) includes a welding part (221) and an abutting part (222). Among them, the welding part (221) is fixedly connected to the connecting boss (213); the abutting part (222) is integrally formed on the welding part (221) and abuts against the curled edge (212); the thickness of the welding part (221) is greater than the thickness of the abutting part (222), and the side of the abutting part (222) away from the connecting piece (3) is flush with the side of the welding part (221) away from the connecting piece (3).

6. The top cover assembly according to claim 2, characterized in that: It further includes a sealing ring (4). The sealing ring (4) is abutted and arranged between the cover plate (1) and the connecting piece (3) and between the cover plate (1) and the lower terminal post plate (21).

7. A top cover assembly according to claim 2 or 6, characterized in that: It further includes a plastic ring (5). The plastic ring (5) is abutted and arranged between the cover plate (1) and the lower terminal post plate (21).

8. The top cover assembly according to claim 1, characterized in that: There are two terminal posts (2). The material of one of the lower terminal post plates (21) is copper, and the materials of the other lower terminal post plate (21) and the two upper terminal post plates (22) are both aluminum.

9. The top cover assembly according to claim 1, wherein: It further includes an explosion-proof valve (6). The explosion-proof valve (6) is fixedly arranged on the cover plate (1).

10. The top cover assembly according to claim 5, characterized in that: Both the fixing boss (211) and the connecting boss (213) are hollow structures and are continuously arranged.

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