Integrated battery cover plate, manufacturing method of battery cover plate and power battery

Abstract

The invention provides an integrated battery cover plate, a manufacturing method of the battery cover plate and a power battery, the integrated battery cover plate comprises a light cover plate, an anti-explosion area is arranged in the middle of the light cover plate, a blasting nick and a safe blasting nick are arranged in the anti-explosion area, the safe blasting nick is located in the middle of the blasting nick, and the safe blasting nick is located in the middle of the light cover plate. And the blasting nick, the safe blasting nick and the light cover plate are integrally punched and formed. According to the integrated battery cover plate, the blasting nick, the safe blasting nick and the light cover plate are subjected to integrated punch forming, and compared with an existing mode that an anti-explosion valve and the light cover plate are welded together through laser, deformation of the blasting nick and the safe blasting nick caused by laser welding can be avoided, and the safety of a power battery is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to an integrated battery cover, a method for manufacturing a battery cover, and a power battery. Background Art

[0002] During the production process of the new energy battery cover, the explosion-proof valve and the light cover are connected together through a laser welding process. In this process, the explosion-proof valve and the light cover need to be stamped separately before laser welding. The temperature generated during laser welding can be as high as 600 degrees or more. Since there are bursting marks on the explosion-proof valve, the bursting marks are easily affected by high temperature and deformed, which in turn affects the normal explosion of the explosion-proof valve. The bursting mark is the weakest part of the explosion-proof valve. When the pressure inside the battery reaches a certain value due to external force squeezing, vibration or high temperature heating, the bursting mark on the explosion-proof valve opens to release the pressure inside the battery to prevent the battery from exploding due to the increase in internal pressure of the battery. However, since the explosion-proof valve and the light cover are welded together through a laser welding process, it is easy to cause the bursting mark to deform, reducing the reliability of the explosion-proof valve. Summary of the invention

[0003] The embodiments of the present application provide an integrated battery cover, a method for manufacturing the battery cover, and a power battery to solve the problems existing in the related technologies. The technical solutions are as follows:

[0004] In a first aspect, an embodiment of the present application provides an integrated battery cover, including a light cover, wherein an explosion-proof area is provided in the middle of the light cover, blasting marks and safety blasting marks are provided in the explosion-proof area, the safety blasting marks are located in the middle of the blasting marks, and the blasting marks and the safety blasting marks are stamped integrally with the light cover.

[0005] In one embodiment, blasting marks are arranged on the upper surface and the lower surface of the explosion-proof area, and the blasting marks on the upper surface and the lower surface of the explosion-proof area are opposite to each other. The blasting marks arranged on the upper surface of the explosion-proof area are recessed from the upper surface of the explosion-proof area to the lower surface of the explosion-proof area, and the blasting marks arranged on the lower surface of the explosion-proof area are recessed from the lower surface of the explosion-proof area to the upper surface of the explosion-proof area.

[0006] In one embodiment, the safety blasting notch is disposed on the upper surface of the explosion-proof region, and the safety blasting notch is recessed from the upper surface of the explosion-proof region to the lower surface of the explosion-proof region.

[0007] In one embodiment, the cross-sections of the blasting notch and the safety blasting notch are both trapezoidal structures, and the angle between two side edges of the trapezoidal structure is 60±2 degrees.

[0008] In one embodiment, a circular groove is provided on the light cover plate, the circular groove is located inside the explosion-proof area, the circular groove is located on the upper surface and the lower surface of the explosion-proof area, and the blasting mark and the safety blasting mark are located inside the circular groove.

[0009] In one embodiment, a positive pole hole and a negative pole hole are provided on the optical cover plate, a positive pole is installed in the positive pole hole, a negative pole is installed in the negative pole hole, and a liquid injection hole is opened between the positive pole hole and the negative pole hole.

[0010] In a second aspect, an embodiment of the present application provides a power battery, comprising an integrated battery cover as described in any one of the above items.

[0011] In a third aspect, an embodiment of the present application provides a method for manufacturing a battery cover, the method for manufacturing a battery cover is used to manufacture an integrated battery cover as described in any one of the above items, and the manufacturing method comprises the following steps:

[0012] S1: Select an explosion-proof area on the light cover plate, and stretch the explosion-proof area upward to form an upward convex area;

[0013] S2: stretching the middle part of the upward convex area downward to form a downward convex area, wherein the bottom height of the downward convex area is higher than the bottom height of the light cover plate;

[0014] S3: punching a blasting notch and a safety blasting notch on the downwardly protruding area, and the safety blasting notch is located in the middle of the blasting notch.

[0015] In one embodiment, after step S1, the method further includes:

[0016] The smooth cover plate is trimmed, and a positive pole hole and a negative pole hole are punched on the smooth cover plate, and the explosion-proof area is located between the positive pole hole and the negative pole hole;

[0017] After step S2, the method further includes:

[0018] A circular groove is punched around the edge of the downwardly protruding area. The circular groove is located on the upper surface and the lower surface of the downwardly protruding area, and the circular groove located on the upper surface of the downwardly protruding area corresponds to the circular groove located on the lower surface of the downwardly protruding area.

[0019] In one embodiment, the cross section of the area between the blasting notch and the safety blasting notch is a convex arc-shaped structure.

[0020] The advantages or beneficial effects of the above technical solution include at least:

[0021] The embodiment of the present application provides an integrated battery cover, including a light cover, wherein an explosion-proof area is provided in the middle of the light cover, and a blasting notch and a safety blasting notch are provided in the explosion-proof area, and the safety blasting notch is located in the middle of the blasting notch, and the blasting notch and the safety blasting notch are integrally stamped and formed with the light cover. Since the blasting notch and the safety blasting notch are provided in the blasting area, when a certain pressure value is reached inside the power battery, the blasting notch and the safety blasting notch are opened at the weakest point, releasing the internal pressure of the power battery, preventing the battery from catching fire and exploding due to increased pressure inside the power battery, and ensuring the safety of the power battery. The integrated battery cover of the embodiment of the present application integrally stamps and forms the blasting notch, the safety blasting notch and the light cover, and compared with the existing explosion-proof valve and the light cover being laser welded together, the deformation of the blasting notch and the safety blasting notch caused by laser welding can be avoided, thereby improving the safety of the power battery.

[0022] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present application will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0024] Figure 1 is a cross-sectional view of an integrated battery cover;

[0025] Figure 2 A cross-sectional view of a light cover plate of an integrated battery cover plate;

[0026] Figure 3 It is the front view of the light cover;

[0027] Figure 4 for Figure 3 A cross-sectional view of

[0028] Figure 5 This is a front view of the light cover plate after the upward convex area is punched out;

[0029] Figure 6 for Figure 5 A cross-sectional view of

[0030] Figure 7 This is a front view after a downward convex area is formed by punching on the smooth cover plate;

[0031] Figure 8 for Figure 7 A cross-sectional view of

[0032] Fig. 9 The front view of the circular groove formed by punching on the smooth cover plate;

[0033] Fig.10 for Fig. 9 A cross-sectional view of

[0034] Fig.11 This is the main view after the blasting notch and the safety blasting notch are punched out on the smooth cover plate;

[0035] Fig.12 for Fig.11 A cross-sectional view of

[0036] Description of reference numerals:

[0037] 1. Bare cover; 2. Explosion-proof area; 3. Blasting notch 3; 4. Safety blasting notch 3; 5. Circular sink; 6. Positive pole hole; 7. Negative pole hole; 8. Positive pole; 9. Negative pole; 10. Liquid injection hole; 11. Upward raised area; 12. Downward raised area. DETAILED DESCRIPTION

[0038] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present application. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0039] Embodiment 1:

[0040] like Figure 1 , Figure 2 As shown, the embodiment of the present application provides an integrated battery cover, including a light cover 1, an explosion-proof area 2 is provided in the middle of the light cover 1, a blasting notch 3 and a safety blasting notch 4 are provided in the explosion-proof area 2, the safety blasting notch 4 is located in the middle of the blasting notch 3, and the blasting notch 3 and the safety blasting notch 4 are integrally stamped and formed with the light cover 1

[0041] In this embodiment, since the blasting marks 3 and the safety blasting marks 4 are arranged in the blasting area, when a certain pressure value is reached inside the power battery, the blasting marks 3 and the safety blasting marks 4 are opened at the weakest point to release the internal pressure of the power battery, prevent the battery from catching fire and exploding due to the increase in pressure inside the power battery, and ensure the safety of the power battery. The integrated battery cover of the embodiment of the present application integrally stamps the blasting marks 3, the safety blasting marks 4 and the light cover 1, which can avoid the deformation of the blasting marks 3 and the safety blasting marks 4 caused by laser welding compared to the existing explosion-proof valve and the light cover 1, thereby improving the safety of the power battery.

[0042] In this embodiment, since the blasting mark 3 and the safety blasting mark 4 are provided in the blasting area, after the blasting mark 3 fails in function, the safety blasting mark 4 can be activated, thereby further ensuring that the pressure can be normally released when the internal pressure of the power battery is too high, playing a role of dual protection.

[0043] In the prior art, the toughness of the middle area of ​​the explosion-proof valve is relatively weak. During the process of adding electrolyte to the power battery, the flow of electrolyte will cause the explosion-proof area to fluctuate up and down, thereby damaging the explosion-proof area and affecting the normal explosion pressure relief of the explosion-proof valve. In this embodiment, by adding the safety explosion-proof mark 4, it is helpful to decompose the mechanical stress caused by the flow of electrolyte, improve the toughness and strength of the explosion-proof area 2, and avoid the up and down fluctuation phenomenon.

[0044] In one embodiment, the blasting marks 3 are arranged on the upper surface and the lower surface of the explosion-proof area 2, and the blasting marks 3 on the upper surface and the lower surface of the explosion-proof area 2 are located opposite to each other. The blasting marks 3 arranged on the upper surface of the explosion-proof area 2 are recessed from the upper surface of the explosion-proof area 2 to the lower surface of the explosion-proof area 2, and the blasting marks 3 arranged on the lower surface of the explosion-proof area 2 are recessed from the lower surface of the explosion-proof area 2 to the upper surface of the explosion-proof area 2.

[0045] The safety blasting notch 4 is arranged on the upper surface of the explosion-proof area 2, and the safety blasting notch 4 is recessed from the upper surface of the explosion-proof area 2 to the lower surface of the explosion-proof area 2. Preferably, the safety blasting notch 4 is in a cross-shaped structure connected in sequence.

[0046] In one embodiment, the cross-sections of the blasting notch 3 and the safety blasting notch 4 are both trapezoidal structures, the angle between the two sides of the trapezoidal structure is 60±2 degrees, and the bottom thickness of the trapezoidal structure is 0.1±0.01mm. The cross-sections of the blasting notch 3 and the safety blasting notch 4 are convex arc structures.

[0047] The light cover plate 1 is provided with a circular groove 5, which is located inside the explosion-proof area 2, and the circular groove 5 is located on the upper and lower surfaces of the explosion-proof area 2, and the blasting notch 3 and the safety blasting notch 4 are located inside the circular groove 5. Preferably, the circular groove 5 is provided at the opposite positions of the upper and lower surfaces of the light cover plate 1, and the depth of the circular groove 5 is 0.3 mm. The outer side of the circular groove 5 has a circle of protrusions.

[0048] When the angle between the two sides of the trapezoidal structure at the blasting mark 3 is greater than 60 degrees, the circular sink 5 is prone to bulging and deformation, which affects the blasting mark 3 and causes unstable blasting values. Therefore, the angle between the two sides of the trapezoidal structure at the blasting mark 3 is generally set to 60 degrees.

[0049] The optical cover plate 1 is provided with a positive pole hole 6 and a negative pole hole 7, wherein a positive pole 8 is installed in the positive pole hole 6, a negative pole 9 is installed in the negative pole hole 7, and an injection hole 10 is provided between the positive pole hole 6 and the negative pole hole 7. The positive pole 8 and the positive pole hole 6, and the negative pole 9 and the negative pole hole 7 can be fixedly connected by laser welding, and the power battery is charged and discharged through the positive pole 8 and the negative pole 9. Since the injection hole 10 is provided between the positive pole hole 6 and the negative pole hole 7, the electrolyte can be injected into the power battery through the injection hole 10.

[0050] Embodiment 2:

[0051] The present embodiment is described in detail below with reference to the first embodiment:

[0052] An embodiment of the present application provides a power battery, comprising the integrated battery cover as described in the above-mentioned embodiment 1.

[0053] The power battery of this embodiment adopts the integrated battery cover plate described in the first embodiment. Since the light cover plate 1 of the battery cover plate can be directly stamped to form the bursting notch 3 and the safety bursting notch 4, the laser welding of the explosion-proof valve and the light cover plate 1 is avoided, and the high temperature of the laser welding is avoided to affect the bursting notch 3, thereby improving the safety of the power battery. Since the bursting notch 3 and the safety bursting notch 4 are provided, double pressure relief protection is provided to prevent the failure of normal pressure relief due to the failure of the bursting notch 3.

[0054] Embodiment three:

[0055] The present embodiment is described in detail below with reference to the first embodiment:

[0056] like Figures 3 to 12 As shown, the embodiment of the present application provides a method for manufacturing a battery cover, which is used to manufacture an integrated battery cover as described in Example 1. The manufacturing method comprises the following steps: S1: Selecting an explosion-proof area 2 on a light cover 1, stretching the explosion-proof area 2 upward to form an upwardly protruding area 11.

[0057] Before step S1, the

[0058] In one embodiment, before step S1 , the process further includes: trimming the light cover plate 1 , and punching a positive pole hole 6 and a negative pole hole 7 on the light cover plate 1 , wherein the explosion-proof area 2 is located between the positive pole hole 6 and the negative pole hole 7 .

[0059] The material used to make the light cover plate 1 of this embodiment is aluminum, the model of the aluminum is MFX2, and the thickness of the aluminum is 2.0 mm. When making the light cover plate 1, the aluminum is first trimmed to make the shape of the light cover plate 1, and then the positive pole hole 6 and the negative pole hole 7 are punched on the light cover plate 1. After the punching is completed, the aluminum material becomes thinner after the explosion-proof area 2 is stretched upward, and the thickness of the upward protruding area 11 after stretching is thinned from 2.0 mm to 1.5 mm.

[0060] S2: stretching the middle portion of the upwardly protruding area 11 downwardly to form a downwardly protruding area 12 , wherein the bottom height of the downwardly protruding area 12 is higher than the bottom height of the optical cover plate 1 .

[0061] After the explosion-proof area 2 is stretched upward to form the upwardly protruding area 11, the middle part of the explosion-proof area 2 is then stretched downward to form the downwardly protruding area 12. After the downward stretching, the thickness of the downwardly protruding area 12 is reduced from 1.5 mm to 1.0 mm.

[0062] After step S2, the method further includes: punching a circular groove 5 in the middle of the downwardly raised area 12, wherein the circular groove 5 is located on the upper surface and the lower surface of the downwardly raised area 12, and the circular groove 5 located on the upper surface of the downwardly raised area 12 corresponds to the circular groove 5 located on the lower surface of the downwardly raised area 12.

[0063] The depth of the circular groove 5 located on the upper surface of the downwardly protruding area 12 is 0.3 mm, and the depth of the circular groove 5 located on the lower surface of the downwardly protruding area 12 is also 0.3 mm, that is, the thickness of the aluminum material in the area of ​​the circular groove 5 is 0.4 mm. Since the explosion-proof area 2 is first stamped upward and then stamped downward, a circle of protrusions is formed on the outside of the circular groove 5 after the circular groove 5 is stamped.

[0064] S3: punching out a blasting mark 3 and a safety blasting mark 4 on the downwardly protruding area 12 , and the safety blasting mark 4 is located in the middle of the blasting mark 3 .

[0065] After the circular groove 5 is punched, the blasting notch 3 and the safety blasting notch 4 are punched in the circular groove 5, and the safety blasting notch 4 is located in the middle of the blasting notch 3. The safety blasting notch 4 is a cross-shaped structure connected in sequence. The cross section of the area between the blasting notch 3 and the safety blasting notch 4 is a convex arc structure.

[0066] The cross sections of the blasting notch 3 and the safety blasting notch 4 formed by stamping are both trapezoidal structures, the bottom thickness of the trapezoidal structure is 0.1±0.01 mm, and the angle between the two side edges of the trapezoidal structure is 60±2 degrees.

[0067] The battery cover of this embodiment is formed by stamping aluminum. During the stamping process, the aluminum is deformed by the impact force, resulting in stress inside the stamped aluminum. In order to ensure that the blasting mark 3 can blast when the set pressure is reached, the blasting mark 3 needs to be subjected to high-temperature annealing. After high-temperature annealing, the material structure at the blasting mark 3 can be more uniform, the material can be softened, and the stress of the material can be reduced.

[0068] In one embodiment, since the blasting mark 3 and the light cover plate 1 are integrally stamped, the light cover plate 1 cannot be subjected to overall annealing treatment, and therefore only local heating is required for the blasting mark 3 to improve the metallographic structure of the aluminum material there. The heating treatment method may be local heating by laser, local irradiation by xenon lamp, and local induction heating lamp by coil. By locally heating the blasting mark 3, the material structure at the blasting mark 3 can be recrystallized to form a uniform and fine recrystallized structure, thereby reducing the material strength at the blasting mark 3, improving the plasticity at the blasting mark 3, and stabilizing the blasting pressure value.

[0069] The blasting marks 3 and the safety blasting marks 4 of the embodiment of the present application are directly stamped and formed on the light cover plate 1, which can avoid deformation of the blasting marks 3 during the manufacturing process and improve the safety of the power battery. In addition, since the laser welding process is eliminated, the investment in personnel, equipment and materials is reduced, and the manufacturing cost is greatly reduced.

[0070] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0071] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0072] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An integrated battery cover, characterized in that: It comprises a light cover plate, wherein an explosion-proof area is arranged in the middle of the light cover plate, a blasting notch and a safety blasting notch are arranged in the explosion-proof area, the safety blasting notch is located in the middle of the blasting notch, and the blasting notch and the safety blasting notch are integrally stamped and formed with the light cover plate.

2. The integrated battery cover according to claim 1, characterized in that: The blasting marks are arranged on the upper surface and the lower surface of the explosion-proof area, and the blasting marks on the upper surface and the lower surface of the explosion-proof area are located opposite to each other. The blasting marks arranged on the upper surface of the explosion-proof area are recessed from the upper surface of the explosion-proof area to the lower surface of the explosion-proof area, and the blasting marks arranged on the lower surface of the explosion-proof area are recessed from the lower surface of the explosion-proof area to the upper surface of the explosion-proof area.

3. The integrated battery cover according to claim 1, characterized in that: The safety blasting notch is arranged on the upper surface of the explosion-proof area, and the safety blasting notch is recessed from the upper surface of the explosion-proof area to the lower surface of the explosion-proof area.

4. The integrated battery cover according to claim 1, characterized in that: The cross sections of the blasting notch and the safety blasting notch are both trapezoidal structures, and the angle between the two side edges of the trapezoidal structure is 60±2 degrees.

5. The integrated battery cover according to claim 1, characterized in that: A circular groove is provided on the light cover plate, the circular groove is located inside the explosion-proof area, the circular groove is located on the upper surface and the lower surface of the explosion-proof area, and the blasting mark and the safety blasting mark are located inside the circular groove.

6. The integrated battery cover according to any one of claims 1 to 5, characterized in that: The optical cover plate is provided with a positive pole hole and a negative pole hole, a positive pole is installed in the positive pole hole, a negative pole is installed in the negative pole hole, and a liquid injection hole is opened between the positive pole hole and the negative pole hole.

7. A power battery, characterized in that: Comprising the integrated battery cover plate as described in any one of claims 1 to 6.

8. A method for manufacturing a battery cover, characterized in that: The manufacturing method of the battery cover is used to manufacture the integrated battery cover as claimed in any one of claims 1 to 6, and the manufacturing method comprises the following steps: S1: Select an explosion-proof area on the light cover plate, and stretch the explosion-proof area upward to form an upward convex area; S2: stretching the middle area of ​​the upwardly raised area downward to form a downwardly raised area, wherein the bottom height of the downwardly raised area is higher than the bottom height of the optical cover plate; S3: punching a blasting notch and a safety blasting notch in the downwardly protruding area, wherein the safety blasting notch is located in the middle of the blasting notch.

9. The method for manufacturing a battery cover according to claim 8, characterized in that: Before step S1, the method further includes: The optical cover plate is trimmed, and a positive pole hole and a negative pole hole are punched on the optical cover plate, wherein the explosion-proof area is located between the positive pole hole and the negative pole hole; After step S2, the method further includes: The circular groove is formed by punching a circle around the edge of the downwardly protruding area. The circular groove is located on the upper surface and the lower surface of the downwardly protruding area, and the circular groove located on the upper surface of the downwardly protruding area corresponds to the circular groove located on the lower surface of the downwardly protruding area.

10. The method for manufacturing a battery cover according to claim 8, characterized in that: The cross section of the area between the blasting notch and the safety blasting notch is a convex arc-shaped structure.

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