Battery top cover and power battery

Abstract

The present invention discloses a battery top cover and a power battery, wherein the battery top cover comprises a top cover sheet, a positive pole, a negative pole, a positive conductive upper plastic and a negative insulating upper plastic; the top cover sheet comprises a sheet-shaped main body and two pole rings protruding from the upper end face of the main body; two pole mounting holes are provided on the main body, and a pole ring is provided on the periphery of each pole mounting hole; the positive and negative poles are respectively inserted into a pole mounting hole; the positive conductive upper plastic and the negative insulating upper plastic are respectively provided on a pole ring; the lower end face of the main body of the top cover sheet is laser welded with a welding aluminum ring on the periphery of each pole mounting hole, and a sealing ring is provided between the welding aluminum ring and the main body. In the present invention, the top cover sheet is made by an integrated stamping process, and the upper plastic and the top cover sheet are integrally injection molded, which can simplify the production process and reduce the production cost; the reverse side welding aluminum ring can avoid the melting of the positive conductive upper plastic / negative insulating upper plastic, and improve the welding yield.

Description

Technical Field

[0001] The present invention relates to the field of power batteries, and in particular to a battery top cover and a power battery. Background Art

[0002] As environmental issues become increasingly prominent, low-carbon economy has become the mainstream of future economic development. The increasingly severe air quality situation has further promoted the rise of new energy vehicles. Hybrid vehicles and pure electric vehicles, as representatives of new energy vehicles, have gradually been recognized by manufacturers and consumers. As the main power source of new energy vehicles, power batteries have become one of the key components of electric vehicles.

[0003] The power battery top cover currently used in the market usually includes: a top cover sheet with two mounting holes, a positive pole and a negative pole inserted into the mounting holes, a positive conductive plastic sleeved on the outer periphery of the positive pole, a negative insulating plastic sleeved on the outer periphery of the negative pole, and a welding aluminum block welded to the outer end face of the top cover sheet. At present, the welding aluminum block adopts the front welding method. Since the welding aluminum block and the positive conductive plastic and the negative insulating plastic are all arranged on the outer end face of the top cover sheet and are close to each other, the positive conductive plastic and the negative insulating plastic are easily melted due to high temperature during the laser welding process, thereby increasing the defective rate of the product. Summary of the invention

[0004] The object of the present invention is to provide a battery top cover and a power battery, which overcome the defect of the front welding method in the prior art that the plastic on the positive electrode conductor and the plastic on the negative electrode insulation are easily melted.

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

[0006] A battery top cover, comprising a top cover sheet, a positive pole, a negative pole, a positive pole conductive upper plastic and a negative pole insulating upper plastic; the top cover sheet comprises a sheet-shaped main body and two pole rings protruding from the upper end surface of the main body; the main body is provided with two pole mounting holes, and a pole ring is provided on the periphery of each pole mounting hole;

[0007] The positive pole column of the positive pole column and the negative pole column of the negative pole column are respectively inserted into a pole mounting hole; the positive pole conductive upper plastic is arranged on the pole ring corresponding to the positive pole column, and the negative pole insulating upper plastic is arranged on the pole ring corresponding to the negative pole column;

[0008] A welding aluminum ring is laser welded on the lower end surface of the main body of the top cover sheet at the periphery of each pole mounting hole, and a sealing ring is provided between the welding aluminum ring and the positive pole / negative pole.

[0009] Optionally, the top cover piece is formed by integrally stamping an aluminum plate.

[0010] Optionally, the negative electrode insulating upper plastic and the positive electrode conductive upper plastic are injection molded on the top cover sheet at the same time.

[0011] Optionally, the effective penetration depth of the laser welding of the welded aluminum ring is greater than or equal to 0.55 mm.

[0012] Optionally, the lower end surface of the main body of the top cover sheet is provided with an annular mounting position at the outer periphery of each pole mounting hole, and the welding aluminum ring is welded in the annular mounting position.

[0013] Optionally, the battery top cover further includes a lower plastic piece, and the lower plastic piece is buckled and connected to the top cover sheet.

[0014] Optionally, the lower plastic part and the top cover sheet are fused into one by ultrasonic wave.

[0015] Optionally, the battery top cover further includes an explosion-proof valve; the explosion-proof valve is welded to the top cover sheet, and includes an explosion-proof sheet and a protective film arranged on the explosion-proof sheet.

[0016] Optionally, a plurality of through holes are provided at intervals on the outer periphery of the pole ring, and a plurality of protrusions matching the through holes are provided at intervals on the inner peripheries of the positive electrode conductive upper plastic and the negative electrode insulating upper plastic.

[0017] A power battery comprises a battery housing and also comprises a battery top cover as described above, wherein the battery top cover is assembled on the battery housing.

[0018] Beneficial effects of the present invention:

[0019] In the battery top cover provided by the embodiment of the present invention, the top cover sheet composed of the main body and the pole ring is made by an integrated stamping process, which can simplify the production process and reduce the production cost compared with the traditional separate stamping method; the positive electrode conductive upper plastic / negative electrode insulating upper plastic and the top cover sheet are integrally injection molded, which can further simplify the production process and save costs; the welding aluminum ring adopts a reverse welding method, which, compared with the traditional front welding method, can avoid the positive electrode conductive upper plastic / negative electrode insulating upper plastic from being burned due to the high temperature generated by welding, and can also effectively control the welding penetration depth and improve the welding yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1A three-dimensional diagram of a battery top cover provided in an embodiment of the present invention.

[0022] Figure 2 An exploded view of a battery top cover provided in an embodiment of the present invention.

[0023] Illustration Description:

[0024] Top cover sheet 1, positive pole 2, negative pole 3, positive conductive upper plastic 4, negative insulating upper plastic 5, sealing ring 6, welding aluminum ring 7, explosion-proof valve 8, lower plastic part 9, main body 11, pole ring 12, pole mounting hole 111, injection hole 112, explosion-proof hole 113, protective film 81, explosion-proof plate 82. DETAILED DESCRIPTION

[0025] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0027] See also Figure 1 and Figure 2 , Figure 1 and Figure 2 They are respectively an overall structural view and an exploded structural view of the battery top cover provided in the present embodiment. As can be seen from the figures, the battery top cover of the present embodiment includes: a top cover sheet 1, a positive electrode column 2, a negative electrode column 3, a positive electrode conductive upper plastic 4, a negative electrode insulating upper plastic 5, a sealing ring 6, a welded aluminum ring 7, an explosion-proof valve 8, and a lower plastic part 9.

[0028] The top cover sheet 1 includes a main body 11 with a sheet-like structure; the main body 11 is provided with two pole mounting holes 111 for mounting the positive pole 2 / negative pole 3, and also has a liquid injection hole 112; the top cover sheet 1 also includes a pole ring 12 protruding from the periphery of each pole mounting hole.

[0029] In this embodiment, the main body 11 and the pole ring 12 constituting the top cover plate 1 are both made of aluminum, and are integrally stamped from the aluminum during production.

[0030] In the existing design, the main body 11 and the pole ring 12 adopt a separate structural design. During the production process, the main body 11 and the pole ring 12 need to be stamped separately. Not only is the process complicated, but also three sets of stamping dies and three punching machines are required, the cleaning work must be completed alone, and the aluminum waste rate is high, so it consumes a high production cost.

[0031] To this end, this embodiment adopts an integrated stamping method to form the top cover sheet 1 including the main body 11 and the pole ring 12, which simplifies the production process and only requires one set of stamping dies and one punch press to complete it, also reduces the generation of waste, and ultimately can greatly reduce production costs.

[0032] The positive electrode column 2 includes a positive electrode column and a positive electrode bottom plate connected to the bottom of the positive electrode column. The negative electrode column includes a negative electrode column and a negative electrode bottom plate connected to the bottom of the negative electrode column. The positive electrode column of the positive electrode column 2 and the negative electrode column of the negative electrode column 3 are respectively inserted into the corresponding electrode mounting holes, and the upper ends of the positive electrode column and the negative electrode column exceed the upper end surface of the top cover sheet 1.

[0033] The positive conductive upper plastic 4 is injection molded on a pole ring 12 of the top cover sheet 1, and the positive conductive upper plastic 4 is used to achieve the conductive connection between the positive pole 2 and the top cover sheet 1. The negative insulating upper plastic 5 is injection molded on another pole ring 12 of the top cover sheet 1, and the negative insulating upper plastic 5 is used to achieve the insulating connection between the negative pole 2 and the top cover sheet 1.

[0034] The outer periphery of the pole ring 12 is provided with a plurality of through holes at intervals, and the inner periphery of the positive conductive upper plastic 4 and the negative insulating upper plastic 5 is evenly provided with a plurality of bumps matching the through holes to ensure smooth injection molding and improve the reliability of the encapsulation performance.

[0035] For the positive electrode conductive upper plastic 4 and the negative electrode insulating upper plastic 5, this embodiment adopts a method of simultaneously injection molding on the top cover sheet 1 after the positive electrode column 2 and the negative electrode column 3 are placed in the corresponding electrode column mounting holes 111 on the top cover sheet 1, replacing the conventional separate injection molding method, and the injection mold can be reduced from two sets to one set, further reducing the production cost of the battery top cover.

[0036] On the lower end surface of the main body 11 of the top cover sheet 1, an annular mounting position (not shown in the figure) matching the welding aluminum ring 7 is provided on the outer periphery of each pole mounting hole 111. After the positive electrode conductive upper plastic 4 and the negative electrode insulating upper plastic 5 are injection molded on the top cover sheet 1, the welding aluminum ring 7 is installed in the annular mounting position and integrated with the main body 11 by laser welding. The effective penetration depth of laser welding is greater than or equal to 0.55 mm, and the sealing ring 6 is provided between the welding aluminum ring 7 and the main body 11 of the top cover sheet 1 to achieve good airtightness.

[0037] In this embodiment, since the positive conductive upper plastic 4 and the negative insulating upper plastic 5 are located on the upper end surface of the top cover sheet 1, and the sealing ring 6 and the welding aluminum ring 7 are located on the lower end surface of the top cover sheet 1, this embodiment essentially laser welds the welding aluminum ring 7 to the back side of the top cover sheet 1. Compared with the conventional front welding method, this back welding method can effectively avoid the positive conductive upper plastic 4 / negative insulating upper plastic 5 from melting and other damages due to the high temperature caused by the laser welding process, and is more conducive to controlling the welding depth and reducing the welding defect rate.

[0038] The explosion-proof valve 8 is arranged on the top cover sheet 1, and the explosion-proof valve 8 includes a protective film 81 and an explosion-proof plate 82. An explosion-proof hole 113 is provided on the main body 11 of the top cover sheet 1. The explosion-proof plate 82 is arranged in the explosion-proof hole 113, and the protective film 81 is arranged on the explosion-proof plate 82. When the internal pressure of the battery increases, the electrolyte will break through the explosion-proof plate 82, and the heat inside the battery will be released in time and effectively, so as to avoid the battery from exploding due to excessive pressure.

[0039] The lower plastic part 9 is buckled into one with the top cover sheet 1, and the two are tightly connected by ultrasound. The lower plastic part 9 is provided with a plurality of through holes corresponding to the position below the explosion-proof valve 8, which are used to transmit the pressure to the explosion-proof valve 8 when the internal pressure of the battery increases to reduce safety hazards, and at the same time, when the electrolyte is injected into the injection hole 112, the electrolyte can flow into the battery housing.

[0040] In addition, in this embodiment, the material of the positive electrode column 2 is aluminum, the material of the negative electrode column 3 is a copper-aluminum composite material, the material of the positive electrode conductive upper plastic 4 is conductive PPS, and the material of the negative electrode insulating upper plastic 5 is insulating PPS.

[0041] Specifically, the production process of the battery top cover includes:

[0042] (1) The top cover sheet 1 including the main body 11 and the pole ring 12 is integrally stamped and manufactured.

[0043] (2) The positive electrode column 2, the negative electrode column 3 and the top cover sheet 1 are installed into the injection mold, and the positive electrode column 2 and the negative electrode column 3 pass through the corresponding electrode mounting holes on the top cover sheet 1 respectively.

[0044] (3) The positive electrode conductive upper plastic 4 and the negative electrode insulating upper plastic 5 are simultaneously injection molded on the top cover sheet 1 .

[0045] (4) Install the sealing ring 6 and the welding aluminum ring 7 on the lower end surface of the top cover plate 1, and weld the welding aluminum ring 7 to the reverse side of the top cover plate 1.

[0046] (5) After the explosion-proof valve 8 is installed on the top cover sheet 1, the lower plastic part 9 is assembled with the top cover sheet 1 as a whole.

[0047] In summary, in the battery top cover provided in the present embodiment, the top cover sheet 1 including the main body 11 and the pole ring 12 is formed by integral stamping, which can simplify the production process and reduce the production cost compared with the traditional separate stamping method; the positive electrode conductive upper plastic 4 / negative electrode insulating upper plastic 5 is integrally injection molded with the top cover sheet 1, which can further simplify the production process and save costs; the welding aluminum ring 7 is welded to the back side of the top cover sheet 1. Compared with the traditional front welding method, while avoiding the positive electrode conductive upper plastic 4 / negative electrode insulating upper plastic 5 from being burned due to the high temperature generated by welding, it can also effectively control the welding penetration depth and improve the welding yield.

[0048] In addition, this embodiment also provides a power battery, including a battery housing and a battery top cover assembled on the battery housing, the battery top cover is as described above. By using the above battery top cover, the production cost of the power battery can be greatly reduced and the product yield can be improved.

[0049] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery top cover, comprising a top cover sheet, a positive electrode column, a negative electrode column, a positive electrode conductive upper plastic and a negative electrode insulating upper plastic; characterized in that: The top cover sheet includes a sheet-shaped main body and two pole rings protruding from the upper end surface of the main body; the main body is provided with two pole mounting holes, and the outer periphery of each pole mounting hole is provided with a pole ring; The positive pole column of the positive pole column and the negative pole column of the negative pole column are respectively inserted into a pole mounting hole, and the positive pole column and the negative pole column respectively pass through the corresponding pole mounting holes on the top cover sheet; the positive pole conductive upper plastic is arranged on the pole ring corresponding to the positive pole column, and the negative pole insulating upper plastic is arranged on the pole ring corresponding to the negative pole column; wherein the negative pole insulating upper plastic and the positive pole conductive upper plastic are injection molded on the top cover sheet at the same time, and the positive pole conductive upper plastic is used to realize the conductive connection between the positive pole column and the top cover sheet; the negative pole insulating upper plastic is used to realize the insulating connection between the negative pole column and the top cover sheet; The lower end surface of the main body of the top cover sheet is laser welded with a welding aluminum ring at the periphery of each pole mounting hole, and a sealing ring is provided between the welding aluminum ring and the positive pole / negative pole; wherein the sealing ring is provided between the welding aluminum ring and the main body of the top cover sheet to achieve good air tightness.

2. The battery top cover according to claim 1, characterized in that: The top cover piece is formed by integrally punching an aluminum plate.

3. The battery top cover according to claim 1, characterized in that: The effective penetration depth of the laser welding of the welded aluminum ring is greater than or equal to 0.55 mm.

4. The battery top cover according to claim 1, characterized in that: The lower end surface of the main body of the top cover sheet is provided with an annular mounting position at the outer periphery of each pole mounting hole, and the welding aluminum ring is welded in the annular mounting position.

5. The battery top cover according to claim 1, characterized in that: The battery top cover also includes a lower plastic piece, and the lower plastic piece is buckled and connected to the top cover sheet.

6. The battery top cover according to claim 5, characterized in that: The lower plastic part and the top cover sheet are fused into one by ultrasonic wave.

7. The battery top cover according to claim 1, characterized in that: The battery top cover also includes an explosion-proof valve; the explosion-proof valve is welded to the top cover sheet and includes an explosion-proof sheet and a protective film arranged on the explosion-proof sheet.

8. The battery top cover according to claim 1, characterized in that: The outer periphery of the pole ring is evenly provided with a plurality of through holes, and the inner peripheries of the positive electrode conductive upper plastic and the negative electrode insulating upper plastic are evenly provided with a plurality of protrusions matching the through holes.

9. A power battery, comprising a battery housing, characterized in that: It also includes the battery top cover according to any one of claims 1 to 8, wherein the battery top cover is assembled on the battery casing.

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