Sealing structure for liquid injection hole of lithium battery

Abstract

The utility model relates to the technical field of lithium batteries, in particular to a sealing structure of a liquid injection hole of a lithium battery, which comprises a top cover plate, the liquid injection hole is arranged on the top cover plate, a sinking table is arranged at one end of the liquid injection hole positioned on the outer side of the top cover plate, an annular bulge is arranged on the outer side of the top cover plate around the sinking table, and an annular limiting block is arranged on the inner side wall of the annular bulge. A sealing plug is arranged in the liquid injection hole and is in interference fit with the liquid injection hole, a sealing piece is arranged at the top of the sealing plug and is located in the sinking table, a rubber plug is arranged in the annular protrusion, a limiting groove corresponding to the annular limiting block is formed in the outer side wall of the rubber plug, and the annular limiting block is in interference fit with the limiting groove. The rubber plug is arranged to limit the sealing piece, the sealing performance is further improved through the annular limiting block, the annular protrusion and the rubber plug, during sealing, only the sealing plug and the rubber plug need to be plugged in sequence, the spinning procedure is reduced, the sealing effect of a seal is improved, and defective products are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, and more specifically to a sealing structure for a liquid injection hole of a lithium battery. Background Art

[0002] Lithium-ion batteries have the advantages of high energy density, long cycle life, and no pollution. They are widely used in portable electronic products and have been shining in the field of electric vehicles in recent years. Lithium battery filling and sealing are important processes in the post-battery manufacturing process. The existing lithium battery filling and sealing methods basically use direct holes in the cover substrate for filling.

[0003] The existing Chinese utility model patent with announcement number CN216818575U discloses a sealing structure for a lithium battery injection hole and a lithium battery. A sealing structure for a lithium battery injection hole comprises an injection hole arranged on a top cover sheet, the injection hole is a step-shaped through hole arranged on the top cover sheet, an annular protrusion formed integrally with the top cover sheet is arranged around the injection hole, a sealing plug is arranged in the injection hole, and the annular protrusion covers the top of the sealing plug to seal the sealing plug.

[0004] However, the above-mentioned structure subsequently uses a spinning device to spin the annular protrusion. After spinning, the annular protrusion squeezes the sealing sheet to achieve sealing. However, during the spinning process, there may be uneven force, resulting in uneven squeezing of the annular protrusion on the sealing sheet. This uneven squeezing may make some areas too tight to seal, while other areas may not be sealed enough, thereby affecting the overall sealing effect; during the spinning process, if the force is too great, the sealing sheet may be damaged, such as cracks, deformation or wear, etc. These damages may reduce the sealing performance of the sealing sheet. Utility Model Content

[0005] The utility model aims to provide a sealing structure for a lithium battery injection hole, which reduces the spinning process, improves the sealing effect, and reduces the generation of defective products.

[0006] In order to achieve the above purpose, the technical solution of the utility model is as follows:

[0007] A sealing structure for a lithium battery injection hole comprises a top cover sheet, the top cover sheet is provided with an injection hole, a sink is provided at one end of the injection hole located on the outside of the top cover sheet, an annular protrusion is provided on the outside of the top cover sheet around the sink, an annular limit block is provided on the inner side wall of the annular protrusion, a sealing plug is provided in the injection hole, the sealing plug and the injection hole are interference fit, a sealing sheet is provided on the top of the sealing plug, the sealing sheet is located in the sink, a rubber plug is provided in the annular protrusion, a limiting groove corresponding to the annular limit block is provided on the outer side wall of the rubber plug, and the annular limit block is interference fit with the limiting groove.

[0008] Furthermore, the inner diameter of the annular limit block is smaller than the inner diameter of the sinker.

[0009] Furthermore, a first chamfer is provided at the bottom of the sink.

[0010] Furthermore, a second chamfer is provided at the junction of the sink and the injection hole.

[0011] Furthermore, an end of the annular limiting block close to the limiting groove is provided with an arc surface.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] The sealing sheet is limited by setting a rubber plug, and the sealing performance is further improved by using an annular limit block, annular protrusion and rubber plug. When sealing, it is only necessary to insert the sealing plug and the rubber plug in sequence, which reduces the spinning process, improves the sealing effect and reduces the production of defective products. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model.

[0015] 1. Top cover; 101. Liquid injection hole; 102. Sink; 2. Annular protrusion; 3. Annular limit block; 4. Sealing plug; 5. Sealing sheet; 6. Rubber plug; 601. Limiting groove; 7. First chamfer; 8. Second chamfer. DETAILED DESCRIPTION

[0016] like Figure 1 As shown, a sealing structure for a lithium battery injection hole comprises a top cover sheet 1, wherein the top cover sheet 1 is provided with an injection hole 101, and a sink 102 is provided at one end of the injection hole 101 located on the outside of the top cover sheet 1, an annular protrusion 2 is provided on the outside of the top cover sheet 1 around the sink 102, an annular limit block 3 is provided on the inner wall of the annular protrusion 2, a sealing plug 4 is provided in the injection hole 101, the sealing plug 4 and the injection hole 101 are interference fit, a sealing sheet 5 is provided on the top of the sealing plug 4, the sealing sheet 5 is located in the sink 102, a rubber plug 6 is provided in the annular protrusion 2, a limit groove 601 corresponding to the annular limit block 3 is provided on the outer wall of the rubber plug 6, and the annular limit block 3 and the limit groove 601 are interference fit.

[0017] The sealing sheet 5 is limited by setting a rubber plug 6, and the sealing performance is further improved by using the annular limiting block 3, the annular protrusion 2 and the rubber plug 6. When sealing, it is only necessary to insert the sealing plug 4 with the sealing sheet 5 and the rubber plug 6 in sequence, which reduces the spinning process, improves the sealing effect, and reduces the production of defective products.

[0018] The inner diameter of the annular limiting block 3 is smaller than the inner diameter of the sink 102 .

[0019] The bottom of the sink 102 is provided with a first chamfer 7 .

[0020] A second chamfer 8 is provided at the junction of the sink 102 and the injection hole 101 .

[0021] The annular limiting block 3 has an arc-shaped surface at one end close to the limiting groove 601 .

[0022] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A sealing structure for a lithium battery injection hole, characterized in that: The invention comprises a top cover sheet (1), wherein the top cover sheet (1) is provided with a liquid injection hole (101), and a sink (102) is provided at one end of the liquid injection hole (101) located on the outside of the top cover sheet (1), and an annular protrusion (2) is provided on the outside of the top cover sheet (1) around the sink (102), and an annular limiting block (3) is provided on the inner wall of the annular protrusion (2), and a sealing plug (4) is provided in the liquid injection hole (101), and the sealing plug (4) and the liquid injection hole (101) are interference fit, and a sealing sheet (5) is provided on the top of the sealing plug (4), and the sealing sheet (5) is located in the sink (102), and a rubber plug (6) is provided in the annular protrusion (2), and a limiting groove (601) corresponding to the annular limiting block (3) is provided on the outer wall of the rubber plug (6), and the annular limiting block (3) and the limiting groove (601) are interference fit.

2. The sealing structure of the lithium battery injection hole according to claim 1, characterized in that: The inner diameter of the annular limiting block (3) is smaller than the inner diameter of the sinking platform (102).

3. The sealing structure of the lithium battery injection hole according to claim 1, characterized in that: The bottom of the sink (102) is provided with a first chamfer (7).

4. The sealing structure of the lithium battery injection hole according to claim 1, characterized in that: A second chamfer (8) is provided at the junction between the sink (102) and the injection hole (101).

5. The sealing structure of the lithium battery injection hole according to claim 1, characterized in that: An arc-shaped surface is provided on one end of the annular limiting block (3) close to the limiting groove (601).

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