Battery top cover with isolated welding positions

Abstract

The utility model discloses a battery top cover with isolated welding positions. A plate body is provided with a pole assembling hole; at least part of the pole structure is mounted in the pole assembly hole, a welding surface is formed on one side, facing a battery cell in the battery, of the pole structure, and an isolation rubber layer is coated and bonded on the region, with the welding surface, of the pole structure. According to the invention, the exposed copper-aluminum welding part is prevented from being in contact with electrolyte, so that the situation that aluminum reacts with Li ions in the electrolyte under low voltage (negative electrode) to form an LI-AL alloy, the LI-AL alloy falls off for a long time to cause a short-circuit explosion risk is avoided, and the battery is safer to use.

Description

Technical Field

[0001] This utility model belongs to the technical field of components for new energy vehicle batteries, specifically relating to a battery top cover with welded isolation. Background Technology

[0002] New energy vehicle batteries consist of cells, casings, and top covers. The cells are located inside the casing, and the top cover seals the casing to encapsulate the cells. The top cover consists of a plate and terminals mounted on the plate. For the negative electrode, copper-aluminum terminals are generally used. These copper-aluminum terminals are formed by fixing copper and aluminum terminals together using laser welding or ultrasonic welding. However, after laser or ultrasonic penetration welding of copper and aluminum, an aluminum-return phenomenon was found. Furthermore, during welding, the weld area is exposed because the weld is penetrated through one side of the copper terminal. This makes it easy for the exposed weld to come into contact with the electrolyte. Under low voltage (negative electrode), aluminum reacts with Li ions in the electrolyte to form a Li-Al alloy. Over time, this alloy may detach, causing a short circuit and explosion risk. Therefore, improvements are urgently needed. Utility Model Content

[0003] The purpose of this utility model is to provide a battery top cover with welded isolation to overcome the shortcomings of the existing technology.

[0004] To achieve the above objectives, the present invention provides a battery top cover with welded isolation, comprising:

[0005] The plate body is provided with pole assembly holes;

[0006] A terminal post structure, at least partially installed in a terminal post mounting hole, wherein a welding surface is formed on the side of the terminal post structure facing the cell inside the battery, and an adhesive layer is coated and bonded to the area of ​​the terminal post structure with the welding surface, the adhesive layer having a thickness in the axial direction.

[0007] According to the battery top cover with welded isolation as described above, the electrode structure includes a first electrode and a second electrode. The first connecting part of the first electrode and the second connecting part of the second electrode are welded and fixed to each other, so that a welding surface is formed on the side of the second connecting part of the second electrode facing the cell inside the battery.

[0008] According to the battery top cover with welded isolation as described above, the second pole includes a convex bulge, on which a second connecting portion and a cavity located below the second connecting portion are formed. After the second connecting portion is welded and fixed to the first connecting portion of the first pole, a welding mark is formed on the side of the second connecting portion facing the cavity, so that the side with the welding mark is used as the welding surface.

[0009] According to the battery top cover with welded isolation as described above, the plate body is provided with two terminal assembly holes, and terminal structures are installed in both terminal assembly holes. The first terminal of the terminal structure in one terminal assembly hole is made of aluminum and the second terminal is made of copper. The first terminal and the second terminal of the terminal structure in the other terminal assembly hole are both made of aluminum. The side of the second connecting part on the copper second terminal facing the cavity serves as the welding surface for coating the adhesive isolation layer.

[0010] According to the battery top cover with welded isolation as described above, the insulating adhesive layer is made of hot-melt polyolefin electrolyte-resistant adhesive.

[0011] According to the battery top cover with welded isolation as described above, the second pole post also includes an annular protrusion continuously disposed on the outer periphery of the protrusion, and a sealing ring is sleeved on the protrusion, the sealing ring being clamped between the annular protrusion and the back of the plate.

[0012] According to the battery top cover with welded isolation as described above, the electrode structure also includes an upper insulating member, which is clamped and disposed between the area with electrode assembly holes on the front side of the plate and the first electrode.

[0013] According to the battery top cover with welded isolation as described above, the area with the electrode assembly hole on the front side of the plate body is provided with an annular positioning part surrounding the outer peripheral wall of the upper insulator. The outer edge of the upper insulator forms a continuous and protruding annular limiting part. The outer peripheral wall of the first electrode abuts against the inner wall of the annular limiting part. The outer wall of the annular limiting part and the outer peripheral wall of the first upper insulator are both abutting against the inner wall of the annular positioning part. Furthermore, the annular limiting part, the annular positioning part, and the first upper insulator are all polygonal in shape.

[0014] According to the battery top cover with welded isolation as described above, a lower insulating member is fixed on the back of the plate. The lower insulating member is provided with a through hole corresponding to the terminal assembly hole, so that the sealing ring is located in the through hole, and the part of the lower insulating member located on the inner wall of the through hole is clamped by the annular protrusion and the plate.

[0015] The battery top cover with welded isolation according to this utility model has the following beneficial effects:

[0016] The battery top cover of this invention prevents the exposed copper-aluminum weld joint from coming into contact with the electrolyte, thereby avoiding the risk of aluminum reacting with Li ions in the electrolyte to form a LI-AL alloy under low voltage (negative electrode) conditions, which could lead to short circuits and explosions over time. This makes the battery safer to use. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the battery top cover (I).

[0018] Figure 2 This is an exploded view of the battery top cover (I).

[0019] Figure 3 This is an exploded view of the battery top cover (II).

[0020] Figure 4 This is a schematic diagram of the negative electrode's pole structure.

[0021] Figure 5 This is a schematic diagram of the positive electrode pole structure.

[0022] Figure 6 This is a schematic diagram of the battery top cover (II).

[0023] Among them, 1. Plate body; 11. Pole post assembly hole; 12. Positioning recess; 13. Annular positioning protrusion; 2. Pole post structure; 21. First pole post; 22. Second pole post; 23. Sealing ring; 24. Upper insulating component; 211. First connecting part; 221. Second connecting part; 222. Welding surface; 223. Protrusion; 224. Cavity; 225. Annular protrusion; 241. Annular limiting part; 242. Inner hole; 243. Positioning ring; 3. Isolation adhesive layer; 5. Lower insulating component; 51. Through hole. Detailed Implementation

[0024] To enable those skilled in the art to better understand this utility model and to more clearly define the scope of protection claimed by this utility model, the present utility model is described in detail below with reference to certain specific embodiments. It should be noted that the following are only some specific embodiments of the present utility model, and the specific and direct descriptions of related structures are merely for the convenience of understanding the present utility model; the specific features do not necessarily or directly limit the scope of implementation of the present utility model. Conventional choices and substitutions made by those skilled in the art under the guidance of the present utility model should all be considered within the scope of protection claimed by this utility model.

[0025] Example:

[0026] like Figures 1-6As shown in this embodiment, a battery top cover with welded isolation includes a plate 1 and a terminal structure 2. The plate 1 is an aluminum plate, and the plate 1 is provided with a terminal mounting hole 11. The terminal structure 2 is at least partially installed in the terminal mounting hole 11. A welding surface 222 is formed on the side of the terminal structure 2 facing the battery cell. An isolation adhesive layer 3 is coated and bonded to the area of ​​the terminal structure 2 with the welding surface 222. The isolation adhesive layer 3 has a thickness in the axial direction. Specifically, the terminal structure 2 includes a first terminal 21 and a second terminal 22. The first connecting part 211 of the first terminal 21 and the second connecting part 221 of the second terminal 22 are welded and fixed to each other, so that a welding surface 222 is formed on the side of the second connecting part 221 of the second terminal 22 facing the battery cell. This welding method adopts ultrasonic welding or laser welding. The second terminal 22 includes a protrusion 223, which forms... The second connecting part 221 and the cavity 224 located below the second connecting part 221 are welded and fixed to the first connecting part 211 of the first pole post 21, so that a welding mark is formed on the side of the second connecting part 221 facing the cavity 224, and the side with the welding mark is used as the welding surface 222. Therefore, a battery top cover with positive and negative electrodes can be formed based on the above structure. The number of pole post mounting holes 11 provided on the plate body 1 is two, and pole post structures 2 are installed in both pole post mounting holes 11. The first pole post 21 of the pole post structure 2 in one pole post mounting hole 11 is an aluminum pole post and the second pole post 22 is a copper pole post. The first pole post 21 and the second pole post 22 of the pole post structure 2 in the other pole post mounting hole 11 are both aluminum pole posts. The side of the second connecting part 221 on the copper pole post 22 facing the cavity 224 is used as the welding surface 222 for coating the adhesive separation layer 3. Therefore, by using the insulating adhesive layer 3 to cover the welding surface 222 of the copper second electrode post 22, the welding surface 222 is isolated from the electrolyte inside the battery, so as to prevent the electrolyte inside the battery from contacting the welding surface 222. This avoids the situation where aluminum reacts with Li ions in the electrolyte at low voltage (negative electrode) to form a LI-AL alloy, which may cause short circuit and explosion risk over a long period of time, making the battery safer to use.

[0027] Preferably, the isolation adhesive layer 3 is made of hot-melt polyolefin electrolyte-resistant adhesive, and the coating thickness of the isolation adhesive layer 3 is generally in the range of 0.1mm-2mm.

[0028] Preferably, such as Figures 4-6As shown, the second pole post 22 also includes an annular protrusion 225 continuously disposed on the outer periphery of the protrusion 223. A sealing ring 23 is sleeved on the protrusion 223. The sealing ring 23 is clamped between the annular protrusion 225 and the back of the plate 1. The annular protrusion 225 and the protrusion 223 are combined into an integral structure, so that the pole post structure 2 is sealed after being installed in the pole post assembly hole 11.

[0029] Preferably, such as Figures 2-4 As shown, the pole structure 2 also includes an upper insulating member 24. The upper insulating member 24 is clamped and disposed between the area with the pole mounting hole 11 on the front side of the plate 1 and the first pole 21. The upper insulating member 24 is made of plastic material, thereby insulating the front side of the top cover from the first pole 21. The inner hole 242 of the upper insulating member 24 has a downward protruding positioning ring 243 that is inserted into the pole mounting hole 11. The outer peripheral wall of the positioning ring 243 abuts against the inner peripheral wall of the pole mounting hole 11. The positioning ring 243 makes the positioning of the upper insulating member 24 more stable and reliable.

[0030] Preferably, such as Figure 2 and Figure 4 As shown, the area on the front of the plate 1 with the pole mounting hole 11 is provided with an annular positioning part surrounding the outer peripheral wall of the upper insulating member 24. The outer edge of the upper insulating member 24 forms a continuous and protruding annular limiting part 241. The outer peripheral wall of the first pole 21 abuts against the inner wall of the annular limiting part 241. The outer wall of the annular limiting part 241 and the outer peripheral wall of the first upper insulating member 24 are both abutting against the inner wall of the annular positioning part. The annular limiting part 241, the annular positioning part and the first upper insulating member 24 are all polygonal structures. Polygonal structures are generally square. Their structural design allows the first pole 21 to be reliably positioned and improves the torsional resistance after the pole is installed.

[0031] More preferably, the annular positioning part includes an annular positioning protrusion 13, the inner wall of which abuts against the outer peripheral wall of the upper insulating member 24 and the annular limiting part 241.

[0032] More preferably, the annular positioning portion includes a positioning recess 12 that is adapted to the shape of the upper insulating member 24, and the upper insulating member 24 is fitted in the positioning recess 12, with the inner wall of the positioning recess 12 abutting against the outer periphery of the upper insulating member 24.

[0033] In the above, the annular positioning protrusion 13 and the positioning recess 12 can be combined to form a single unit, or only one unit can be selected for setting. The positioning effect is better when both the annular positioning protrusion 13 and the positioning recess 12 are selected for setting simultaneously.

[0034] Preferably, such as Figure 2 and Figure 3As shown, a lower insulating member 5 is fixed on the back of the plate 1. The lower insulating member 5 is provided with a through hole 51 corresponding to the pole mounting hole 11, so that the sealing ring 23 is located in the through hole 51. The part of the lower insulating member 5 located on the inner wall of the through hole 51 is clamped by the annular protrusion 225 and the plate 1. The lower insulating member 5 is made of plastic and insulates the back of the plate 1.

[0035] Finally, in order to improve the positioning effect of the upper insulating member 24 on the front side of the plate 1, an annular locking part can be formed on the outer peripheral wall of the annular limiting part 241. The annular locking part is provided with an annular groove, and the annular positioning protrusion 13 is engaged in the annular groove.

Claims

1. A battery top cover with weld site isolation, characterized by, The utility model relates to a battery pole structure, including: A plate body (1) is provided with a pole assembly hole (11); A pole structure (2) is at least partially installed in the pole assembly hole (11), a welding surface (222) is formed on the pole structure (2) towards the side of the battery cell inside, the area of the pole structure (2) with the welding surface (222) is coated with an isolation glue layer (3), and the isolation glue layer (3) has a thickness in the axial direction.

2. A battery top cover with a welding site isolation according to claim 1, characterized in that, The pole structure (2) includes a first pole (21) and a second pole (22), a first connecting part (211) of the first pole (21) and a second connecting part (221) of the second pole (22) are welded and fixed to each other, so that a welding surface (222) is formed on the second connecting part (221) of the second pole (22) towards the side of the battery cell inside.

3. A battery top cover with a welding site isolation according to claim 2, characterized in that, The second pole (22) includes a convex (223), a second connecting part (221) and a cavity (224) below the second connecting part (221) are formed on the convex (223), and the second connecting part (221) is welded and fixed with the first connecting part (211) of the first pole (21), so that a welding trace is formed on the side of the second connecting part (221) towards the cavity (224), and the side with the welding trace is used as the welding surface (222).

4. A battery top cover with a welding site isolation according to claim 3, characterized in that, The plate body (1) is provided with two pole assembly holes (11), and the pole structure (2) is installed in the two pole assembly holes (11), the first pole (21) of the pole structure (2) in one of the pole assembly holes (11) is an aluminum pole, and the second pole (22) is a copper pole, the first pole (21) and the second pole (22) of the pole structure (2) in the other of the pole assembly holes (11) are both aluminum poles, and the side of the second connecting part (221) of the copper second pole (22) towards the cavity (224) is used as the welding surface (222) for coating the isolation glue layer (3).

5. A battery top cover with a welding site isolation according to claim 4, characterized in that, The isolation glue layer (3) is hot melt polyolefin electrolyte-resistant glue.

6. A battery top cover with a welding site isolation according to claim 4, characterized in that, The second pole (22) further includes an annular convex (225) continuously arranged on the outer periphery of the convex (223), the convex (223) is sleeved with a sealing ring (23), and the sealing ring (23) is clamped between the annular convex (225) and the back surface of the plate body (1).

7. A battery top cover with a welding site isolation according to any one of claims 2-6, characterized in that, The pole structure (2) further includes an upper insulating part (24), and the upper insulating part (24) is clamped and arranged between the area of the plate body (1) with the pole assembly hole (11) and the first pole (21).

8. A battery top cover with a welding site isolation according to claim 7, characterized in that The area of the plate body (1) with the pole assembly hole (11) on the front side is provided with an annular positioning part around the outer peripheral wall of the upper insulating part (24), the outer edge of the upper insulating part (24) forms a continuous and protruding annular limiting part (241), the outer peripheral wall of the first pole (21) is in abutment with the inner wall of the annular limiting part (241), the outer wall of the annular limiting part (241) and the outer peripheral wall of the first upper insulating part (24) are both in abutment with the inner wall of the annular positioning part, and the outer shapes of the annular limiting part (241), the annular positioning part and the first upper insulating part (24) are all polygonal structures.

9. A battery top cover with a welding site isolation according to claim 6, characterized in that, The back side of the plate body (1) is fixed with a lower insulating part (5), the lower insulating part (5) is provided with a through hole (51) corresponding to the pole assembly hole (11), so that the sealing ring (23) is located in the through hole (51), and the inner wall part of the through hole (51) on the lower insulating part (5) is clamped by the annular convex (225) and the plate body (1).

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