Sealing nail structure of large cylindrical battery

Abstract

The utility model discloses a sealing nail structure of a large cylindrical battery. The sealing nail structure comprises a liquid injection hole and a sealing nail which are arranged on a shell or a cover plate, the sealing nail is characterized in that the whole sealing nail is cylindrical, a concentric groove is formed in the inward end of the sealing nail, a sealing ring is fixedly embedded in the groove, and the thickness of the sealing ring is larger than the depth of the groove; the inner diameter of the liquid injection hole is matched with the diameter of the sealing nail, the inward end of the liquid injection hole is provided with an annular boss formed by protruding inwards in the radial direction, the inner hole diameter of the annular boss is smaller than the inner diameter of the sealing ring, the sealing nail is arranged on the liquid injection hole in a matched mode, and the sealing ring is pressed on the annular boss in a sealed mode. The sealing structure has the advantages that the structure is ingenious, the liquid injection hole can be sealed in advance, welding hole explosion caused by electrolyte leakage is avoided, the welding yield is improved, and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a sealing nail structure of a large cylindrical battery. Background Art

[0002] After lithium-ion batteries are filled with electrolyte, sealing nails are usually used to seal the injection holes. Existing sealing nails mainly use round aluminum sheets. This structure cannot play a sealing role before the sealing nails are welded, which can easily lead to electrolyte leakage during welding and cause welding holes. The welding sealing effect is poor, resulting in a low yield rate in the welding process. Utility Model Content

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is: how to provide a sealing nail structure with an ingenious structure that can seal the injection hole in advance to avoid welding holes caused by leakage of electrolyte, thereby facilitating improving the welding yield.

[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0005] A sealing nail structure for a large cylindrical battery, comprising a liquid injection hole and a sealing nail arranged on a shell or a cover plate; characterized in that the sealing nail is cylindrical as a whole, and has a concentrically arranged groove at one end facing inward, a sealing ring is fixedly embedded in the groove, and the thickness of the sealing ring is greater than the depth of the groove; the inner diameter of the liquid injection hole matches the diameter of the sealing nail, and has an annular boss protruding radially inward at one end facing inward, the inner hole diameter of the annular boss is smaller than the inner diameter of the sealing ring, the sealing nail is fitted on the liquid injection hole, and the sealing ring is sealingly pressed on the annular boss.

[0006] With the above structure, the sealing ring and the annular boss are sealed to form a sealing match between the sealing pin and the injection hole before welding, thereby avoiding electrolyte leakage and welding hole explosion, which is beneficial to improving the welding yield. At the same time, since the sealing ring is fixed in the groove, no additional sealing ring installation process is required.

[0007] Furthermore, the groove is in a circular ring shape, and the sealing ring is glued into the groove.

[0008] Furthermore, the outward end of the sealing pin has an annular flange protruding radially outward, and the outward end of the injection hole has a positioning groove extending radially outward, the depth of the positioning groove is consistent with the thickness of the annular flange, and the diameters of the two match; the annular flange fits in the positioning groove.

[0009] In this way, the welding position between the sealing pin and the liquid injection hole is as far away from the middle of the liquid injection hole as possible through the outwardly expanded positioning groove and the annular flange.

[0010] Furthermore, the sealing pin has a convex ridge protruding in the radial direction, and the convex ridge is tightly matched with the inner wall of the injection hole.

[0011] In this way, the sealing pin pressed into the injection hole can keep the sealing ring sealed before welding due to the tight fit between the ridge and the injection hole. On the one hand, it can prevent electrolyte overflow; on the other hand, no additional tooling is required to press the sealing pin during the welding process, making the welding operation more convenient.

[0012] Furthermore, the convex ridge is close to an outward end of the sealing pin.

[0013] In this way, the tight fit state will only be achieved when the sealing pin is about to be fully pressed in, thereby making press-fitting more convenient.

[0014] Furthermore, the convex ridge extends in a ring shape along the circumference of the sealing pin.

[0015] Furthermore, the sealing nail is made of stainless steel or aluminum.

[0016] Furthermore, the sealing ring is made of rubber or polytetrafluoroethylene.

[0017] In summary, the utility model has the advantages of clever structure, being able to seal the injection hole in advance, avoiding electrolyte leakage and causing welding hole explosion, and being beneficial to improving welding yield, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the sealing nail.

[0019] Figure 2 It is a schematic diagram of the cross-sectional structure of the sealing pin and the injection hole. DETAILED DESCRIPTION

[0020] The utility model is further described in detail below in conjunction with the embodiments.

[0021] When implementing: Figure 1 and Figure 2As shown, a sealing nail structure of a large cylindrical battery includes a liquid injection hole 1 and a sealing nail 2 arranged on a shell or a cover plate; the sealing nail 2 is cylindrical as a whole, and has a concentrically arranged groove 21 at one end facing inward, a sealing ring 3 is fixedly embedded in the groove 21, and the thickness of the sealing ring 3 is greater than the depth of the groove 21; the inner diameter of the liquid injection hole 1 matches the diameter of the sealing nail 2, and has an annular boss 11 protruding radially inward at one end facing inward, the inner diameter of the annular boss 11 is smaller than the inner diameter of the sealing ring 3, the sealing nail 2 is fitted on the liquid injection hole 1, and the sealing ring 3 is sealed and pressed on the annular boss 11. In this embodiment, the groove 21 is annular, the sealing ring 3 is glued in the groove 21, the sealing nail 2 is made of aluminum, and the sealing ring 3 is made of polytetrafluoroethylene.

[0022] like Figure 1 As shown, the outward end of the sealing pin 2 has an annular flange 22 protruding radially outward, and the outward end of the injection hole 1 has a positioning groove 12 extending radially outward, the depth of the positioning groove 12 is consistent with the thickness of the annular flange 22, and the diameters of the two match; the annular flange 22 fits in the positioning groove 12.

[0023] With the above structure, the sealing ring and the annular boss are sealed to form a sealing match between the sealing pin and the injection hole before welding, thereby avoiding electrolyte leakage and welding hole explosion, which is beneficial to improving the welding yield. At the same time, since the sealing ring is fixed in the groove, no additional sealing ring installation process is required.

[0024] In this embodiment, the sealing pin 2 has a ridge 23 protruding in the radial direction, the ridge 23 is tightly matched with the inner wall of the injection hole 1, and the ridge extends in a ring shape along the circumference of the sealing pin 2 and is close to the outward end of the sealing pin 2.

[0025] Before welding, press the sealing pin into the injection hole. The sealing pin pressed into the injection hole can keep the sealing ring sealed before welding due to the tight fit between the ridge and the injection hole. On the one hand, it can prevent electrolyte overflow. On the other hand, no additional tooling is required to press the sealing pin during the welding process, making the welding operation more convenient.

[0026] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A sealing nail structure for a large cylindrical battery, comprising a liquid injection hole (1) and a sealing nail (2) arranged on a housing or a cover plate; characterized in that: The sealing pin (2) is cylindrical in shape as a whole, and has a concentrically arranged groove (21) at one end facing inwards, a sealing ring (3) is fixedly embedded in the groove (21), and the thickness of the sealing ring (3) is greater than the depth of the groove (21); the inner diameter of the injection hole (1) matches the diameter of the sealing pin (2), and has an annular boss (11) protruding radially inwards at one end facing inwards, the inner hole diameter of the annular boss (11) is smaller than the inner diameter of the sealing ring (3), the sealing pin (2) is fitted on the injection hole (1), and the sealing ring (3) is sealingly pressed on the annular boss (11).

2. The sealing nail structure according to claim 1, characterized in that: The groove (21) is in the shape of a circular ring, and the sealing ring (3) is glued into the groove (21).

3. The sealing nail structure according to claim 1, characterized in that: The outward end of the sealing pin (2) has an annular flange (22) protruding radially outward, and the outward end of the injection hole (1) has a positioning groove (12) extending radially outward. The depth of the positioning groove (12) is consistent with the thickness of the annular flange (22), and the diameters of the two are matched; the annular flange (22) is fitted in the positioning groove (12).

4. The sealing nail structure according to claim 1, characterized in that: The sealing pin (2) has a convex ridge protruding in the radial direction, and the convex ridge is tightly matched with the inner wall of the injection hole (1).

5. The sealing nail structure according to claim 4, characterized in that: The convex ridge is close to the outward end of the sealing pin (2).

6. The sealing nail structure according to claim 4, characterized in that: The convex ridge extends in a ring shape along the circumference of the sealing pin (2).

7. The sealing nail structure according to claim 1, characterized in that: The sealing nail (2) is made of stainless steel or aluminum.

8. The sealing nail structure according to claim 1, characterized in that: The sealing ring (3) is made of rubber or polytetrafluoroethylene.

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