Seal welding structure capable of reducing seal welding explosion point and sealing method of seal welding structure

Abstract

The invention discloses a seal welding structure capable of reducing seal welding explosion points and a sealing method thereof.The seal welding structure comprises a cover plate, a liquid injection opening is formed in the inner side of the cover plate, and a sealing groove is formed in the liquid injection opening; the plastic nail is arranged on the inner side of the liquid injection opening; the sealing metal sheet is arranged on the inner side of the sealing groove, and a welding seam fixed with the cover plate through penetration welding is formed on the edge of the inner side of the sealing metal sheet; wherein the sealing groove comprises a first connecting groove and a second connecting groove, and the second connecting groove is formed in the first connecting groove; through the arrangement of the first connecting groove, the second connecting groove, the welding seam for penetration welding and the sealing metal sheet, the device can well avoid electrolyte residues so as to avoid the influence of welding explosion points on welding, meanwhile, the welding mode is improved, the penetration welding is adopted to reduce the stress borne by the sealing metal sheet in the horizontal direction, and the sealing performance of the sealing metal sheet is improved. Large gaps existing in original splicing inclined planes are reduced, and the sealing effect is improved.

Description

Technical Field

[0001] The invention specifically relates to a sealing welding structure and a sealing method thereof for reducing a sealing welding explosion point. Background Art

[0002] Lithium battery is a rechargeable battery widely used in portable electronic devices, electric vehicles, energy storage systems and other fields. Glue nails and sealing aluminum sheets are important components in the assembly process of lithium-ion batteries, especially square aluminum shell batteries. Its main function is to ensure that the battery can be completely sealed at the injection port of the cover after the electrolyte is injected to avoid electrolyte leakage and external air or moisture from entering, thereby ensuring the safety of the battery and long-term stable operation.

[0003] In the prior art, when sealing the liquid injection port of the cover plate, the liquid injection port is first sealed by a glue nail, and then the liquid injection port is cleaned, and then the sealing aluminum sheet is fixed to the welding groove of the cover plate by splicing welding. Figure 4 As shown, however, the R corner of the welding groove cannot be effectively cleaned, and residual electrolyte crystals will remain. Although the welding molten pool will not reach the bottom R corner, the welding heat and metal vapor will vaporize the electrolyte crystals and dissolve into the molten pool after vaporization. If the molten pool cannot be discharged in time, it will cause welding explosion points. In addition, the gap of the traditional splicing welding seam is large, which affects the sealing effect. For this reason, we propose a sealing welding structure and a sealing method to reduce the sealing welding explosion point. Summary of the invention

[0004] The purpose of the present invention is to provide a sealing welding structure and a sealing method thereof that reduce the explosion point of the sealing weld, so as to solve the problem proposed in the above background technology that when the existing battery filling port is sealed, electrolyte crystallization exists at the R corner of the welding groove where the sealing aluminum sheet and the cover plate are welded, and welding explosion points may occur.

[0005] To achieve the above object, the present invention provides the following technical solution: a sealing welding structure for reducing the explosion point of sealing welding, comprising:

[0006] A cover plate, wherein a liquid injection port is provided on the inner side of the cover plate, and a sealing groove is provided on the liquid injection port;

[0007] A rubber nail is arranged inside the liquid injection port;

[0008] A sealing metal sheet is arranged inside the sealing groove, and a welding seam is formed on the inner edge of the sealing metal sheet and fixed to the cover plate by penetration welding;

[0009] Wherein, the sealing groove includes a first connecting groove and a second connecting groove, the first connecting groove is provided with the second connecting groove, and the inner diameter of the second connecting groove is greater than the inner diameter of the first connecting groove.

[0010] It is convenient to form a welding seam through penetration welding to avoid the situation in which the welding seam is at the contact point between the sealing metal sheet and the cover plate during traditional splicing welding, resulting in a larger welding seam gap and affecting the sealing effect. The welding seam formed by penetration welding can reduce the welding seam gap and at the same time can well reduce the horizontal stress on the sealing metal sheet. The sealing groove is composed of two sections, the first connecting groove and the second connecting groove, which can effectively reduce the electrolyte residue on the inner side of the second connecting groove after cleaning and cause the explosion point during welding, so as to improve the cleanliness of the second connecting groove so as to improve the welding effect.

[0011] Preferably, a sealing protrusion is fixed on the lower surface of the sealing metal sheet, and the height of the sealing protrusion corresponds to the depth of the first connecting groove.

[0012] This facilitates better sealing of the liquid injection port.

[0013] Preferably, the outer surface of the sealing metal sheet has a connecting bevel, and the inner surface of the second connecting groove is provided with a first sealing bevel corresponding to the connecting bevel.

[0014] It is convenient for better contact sealing effect. At the same time, the weld seam using penetration welding can effectively reduce the larger weld seam gap existing in splicing welding.

[0015] Preferably, the inner wall of the first connecting groove has a second sealing slope having the same inclination as the first sealing slope.

[0016] To facilitate better sealing.

[0017] Preferably, the inner diameter of the liquid injection port is the same as the outer diameter of the glue nail, and the inner diameter of the liquid injection port is smaller than the inner diameter of the first connecting groove.

[0018] It is convenient to seal the liquid injection port more comprehensively to reduce leakage of electrolyte from the liquid injection port.

[0019] Preferably, the sealing metal sheet is made of aluminum.

[0020] It is convenient to reduce costs and facilitate welding operations.

[0021] Preferably, the material of the rubber nail is EPDM rubber or silicone.

[0022] For better corrosion resistance.

[0023] Preferably, the outer diameter of the rubber nail increases from the lower end to the upper end.

[0024] A sealing method for a sealing welding structure for reducing a sealing welding explosion point comprises the following steps:

[0025] Step A: After injecting liquid through the injection port, insert the glue nail into the inner side of the injection port for sealing;

[0026] Step B: Clean the inner side of the sealing groove by laser or dry ice, and then place the sealing metal sheet into the inner side of the sealing groove, so that the sealing protrusion extends into the inner side of the first connecting groove, and the connecting inclined surface contacts the first sealing inclined surface;

[0027] Step C: Fix the sealing metal sheet and the cover plate by penetration welding. At this time, the welding seam corresponds to the second connection groove.

[0028] It is convenient to avoid the influence of residual electrolyte crystallization on welding by changing the shape of the sealing groove and the structure of the sealing metal sheet, thereby saving a lot of labor for manually scrubbing the injection hole, reducing the welding explosion point, and improving the qualified rate of sealing welding.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] This patent avoids the traditional welding groove by providing a first connecting groove, a second connecting groove, a welding seam of penetrating welding and a sealing metal sheet, which is relatively simple. After liquid is injected through the liquid injection port of the cover plate, the electrolyte remains at the R corner of the welding groove. The common splicing welding is prone to explosion points. This device can well avoid the residual electrolyte to avoid the influence of welding explosion points on welding. At the same time, by improving the welding method, penetrating welding is used to reduce the horizontal stress of the sealing metal sheet, reduce the large gap in the original splicing inclined surface, and improve the sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of the present invention;

[0032] Figure 2 It is a schematic diagram of the sealing groove structure of the present invention;

[0033] Figure 3 It is a schematic diagram of the sealing metal sheet structure of the present invention;

[0034] Figure 4 This is a schematic diagram of the existing splicing welding structure.

[0035] In the figure: 1, cover plate; 2, rubber nail; 3, sealing metal sheet; 301, sealing protrusion; 302, connecting slope; 4, sealing groove; 401, first connecting groove; 402, second connecting groove; 4021, first sealing slope; 5, welding seam; 6, liquid filling port. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments 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.

[0037] See also Figure 1-Figure 4 The present invention provides a technical solution: a sealing welding structure for reducing the explosion point of sealing welding, comprising:

[0038] A cover plate 1, a liquid injection port 6 is provided on the inner side of the cover plate 1, and a sealing groove 4 is provided on the liquid injection port 6;

[0039] The glue nail 2 is arranged inside the liquid injection port 6;

[0040] The sealing metal sheet 3 is arranged inside the sealing groove 4, and a welding seam 5 is formed on the inner edge of the sealing metal sheet 3 and fixed to the cover plate 1 by penetration welding;

[0041] The sealing groove 4 includes a first connecting groove 401 and a second connecting groove 402 . The first connecting groove 401 is provided with the second connecting groove 402 , and the inner diameter of the second connecting groove 402 is greater than the inner diameter of the first connecting groove 401 .

[0042] The welding seam 5 is formed by penetration welding to avoid the welding seam being at the contact point between the sealing metal sheet 3 and the cover plate 1 during traditional splicing welding, resulting in a larger welding seam gap and affecting the sealing effect. The welding seam 5 formed by penetration welding can reduce the welding seam gap and at the same time can well reduce the horizontal stress on the sealing metal sheet 3. The sealing groove 4 is composed of two sections, the first connecting groove 401 and the second connecting groove 402, which can effectively reduce the electrolyte residue after cleaning to the inner side of the second connecting groove 402 causing the explosion point during welding, and it is convenient to improve the cleanliness of the second connecting groove 402 to improve the welding effect.

[0043] Preferably, a sealing protrusion 301 is fixed on the lower surface of the sealing metal sheet 3 , and the height of the sealing protrusion 301 corresponds to the depth of the first connecting groove 401 .

[0044] This facilitates better sealing of the liquid injection port 6.

[0045] Preferably, the outer surface of the sealing metal sheet 3 has a connecting inclined surface 302 , and the inner surface of the second connecting groove 402 is provided with a first sealing inclined surface 4021 corresponding to the connecting inclined surface 302 .

[0046] This facilitates a better contact sealing effect, and the weld seam 5 using penetration welding can effectively reduce the larger weld seam gap existing in the splicing welding.

[0047] Preferably, the inner wall of the first connecting groove 401 has a second sealing slope having the same inclination as the first sealing slope 4021 .

[0048] To facilitate better sealing.

[0049] Preferably, the inner diameter of the liquid injection port 6 is the same as the outer diameter of the glue nail 2 , and the inner diameter of the liquid injection port 6 is smaller than the inner diameter of the first connecting groove 401 .

[0050] This facilitates more comprehensive sealing of the liquid injection port 6 to reduce leakage of electrolyte from the liquid injection port 6 .

[0051] Preferably, the sealing metal sheet 3 is made of aluminum.

[0052] It is convenient to reduce costs and facilitate welding operations.

[0053] Preferably, the material of the rubber nail 2 is EPDM rubber or silicone.

[0054] For better corrosion resistance.

[0055] Preferably, the outer diameter of the rubber nail 2 increases from the lower end to the upper end.

[0056] A sealing method for a sealing welding structure for reducing a sealing welding explosion point comprises the following steps:

[0057] Step A: After the liquid is injected through the liquid injection port 6, the glue nail 2 is inserted into the inner side of the liquid injection port 6 for sealing;

[0058] Step B: Clean the inner side of the sealing groove 4 by laser or dry ice, and then place the sealing metal sheet 3 into the inner side of the sealing groove 4, so that the sealing protrusion 301 extends into the inner side of the first connecting groove 401, and the connecting inclined surface 302 contacts the first sealing inclined surface 4021;

[0059] Step C: Fix the sealing metal sheet 3 and the cover plate 1 by penetration welding. At this time, the welding seam 5 corresponds to the second connecting groove 402.

[0060] It is convenient to avoid the influence of residual electrolyte crystallization on welding by changing the shape of the sealing groove 4 and the structure of the sealing metal sheet 3, thereby saving a lot of labor for manually scrubbing the injection hole, reducing the welding explosion point, and improving the qualified rate of sealing welding.

[0061] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A sealing welding structure for reducing the explosion point of sealing welding, characterized in that: include: A cover plate (1), wherein a liquid injection port (6) is provided on the inner side of the cover plate (1), and a sealing groove (4) is provided on the liquid injection port (6); A rubber nail (2) is arranged inside the liquid injection port (6); A sealing metal sheet (3) is arranged inside the sealing groove (4), and a welding seam (5) is formed on the inner edge of the sealing metal sheet (3) and fixed to the cover plate (1) by penetration welding; The sealing groove (4) comprises a first connecting groove (401) and a second connecting groove (402); the second connecting groove (402) is provided on the first connecting groove (401); and the inner diameter of the second connecting groove (402) is greater than the inner diameter of the first connecting groove (401).

2. A sealing welding structure for reducing the explosion point of sealing welding according to claim 1, characterized in that: A sealing protrusion (301) is fixed on the lower surface of the sealing metal sheet (3), and the height of the sealing protrusion (301) corresponds to the depth of the first connecting groove (401).

3. A sealing welding structure for reducing the explosion point of sealing welding according to claim 1, characterized in that: The outer surface of the sealing metal sheet (3) is provided with a connecting bevel (302), and the inner surface of the second connecting groove (402) is provided with a first sealing bevel (4021) corresponding to the connecting bevel (302).

4. A sealing welding structure for reducing the explosion point of sealing welding according to claim 3, characterized in that: The inner wall of the first connecting groove (401) has a second sealing slope having the same inclination as the first sealing slope (4021).

5. A sealing welding structure for reducing the explosion point of sealing welding according to claim 1, characterized in that: The inner diameter of the liquid injection port (6) is the same as the outer diameter of the glue nail (2), and the inner diameter of the liquid injection port (6) is smaller than the inner diameter of the first connecting groove (401).

6. A sealing welding structure for reducing the explosion point of sealing welding according to claim 1, characterized in that: The sealing metal sheet (3) is made of aluminum.

7. A sealing welding structure for reducing the explosion point of sealing welding according to claim 1, characterized in that: The material of the rubber nail (2) is preferably EPDM rubber or silicone.

8. The sealing welding structure for reducing the explosion point of sealing welding according to claim 1, characterized in that: The outer diameter of the rubber nail (2) increases from the lower end to the upper end.

9. A sealing method for a sealed welding structure for reducing the explosion point of sealing welding according to any one of claims 1 to 8, characterized in that: The steps include: Step A: After liquid is injected through the liquid injection port (6), the glue nail (2) is inserted into the inner side of the liquid injection port (6) for sealing; Step B: Cleaning the inner side of the sealing groove (4) by laser or dry ice, and then placing the sealing metal sheet (3) into the inner side of the sealing groove (4), wherein the sealing protrusion (301) extends into the inner side of the first connecting groove (401), and the connecting inclined surface (302) contacts the first sealing inclined surface (4021); Step C: Fix the sealing metal sheet (3) and the cover plate (1) by penetration welding, and the welding seam (5) corresponds to the second connecting groove (402).

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