Sealing nail assembly and cylindrical battery

Abstract

The utility model discloses a sealing nail assembly and a cylindrical battery. The sealing nail assembly comprises a liquid injection hole and a sealing nail, wherein the liquid injection hole is formed in a shell or a cover plate; a first stepped hole and a second stepped hole are sequentially formed in the outer end of the liquid injection hole from inside to outside, and the diameters of the first stepped hole, the second stepped hole, the first stepped hole and the liquid injection hole are sequentially reduced; the sealing nail comprises a welding plate matched with the second stepped hole, the middle of the welding plate is provided with a sealing column formed through coaxial protruding, the diameter of the sealing column is matched with the diameter of the first stepped hole, a sealing gasket is arranged at the end of the sealing column, and the length of the sealing column is matched with the depth of the first stepped hole; an annular protruding edge formed in a protruding mode is arranged on the outer circle face of the sealing column in the circumferential direction, and the annular protruding edge is tightly matched with the first step hole. The sealing nail assembly and the cylindrical battery provided by the utility model have the advantages that the structure is reasonable, the influence of electrolyte on a welding surface can be avoided, the yield can be 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 assembly and a cylindrical battery. Background Art

[0002] Usually, the sealing nails of lithium-ion cylindrical batteries adopt a flat structure, and the sealing effect is mainly guaranteed by the molten pool and molten depth formed after laser welding. During welding, the electrolyte climbs to the welding surface due to the high temperature of laser welding, contaminating the welding surface, and the welding is prone to holes. The welding sealing effect is poor, resulting in a low yield of 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 assembly and a cylindrical battery with a reasonable structure, which can avoid the influence of the electrolyte on the welding surface and is conducive to improving the yield rate.

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

[0005] A sealing nail assembly, comprising an injection hole arranged on a shell or a cover plate and a sealing nail sealingly fitted on the injection hole; characterized in that the outer end of the injection hole has a first step hole and a second step hole arranged in sequence from the inside to the outside, and the diameters of the first step hole, the second step hole, the first step hole and the injection hole become smaller in sequence; the sealing nail comprises a welding plate matching the second step hole, the middle part of the welding plate has a sealing column formed by coaxial protrusions, the diameter of the sealing column matches the diameter of the first step hole, a sealing gasket is arranged at the end of the sealing column, the length of the sealing column matches the depth of the first step hole, so that the sealing gasket can be sealingly fitted between the sealing column and the end face of the first step hole; an annular convex ridge formed by protrusions is arranged on the outer circumferential surface of the sealing column along the circumferential direction, and the annular convex ridge is tightly fitted on the first step hole.

[0006] With the above structure, since a sealing gasket is provided, after the sealing column is pressed into the first step hole, the sealing gasket can be sealed between the sealing column and the first step hole. At the same time, the sealing column is tightly matched with the first step hole through the annular flange, thereby preventing the sealing column from moving under the reverse elastic action of the sealing gasket, and ensuring that the sealing gasket is always in a sealed state. In this way, the tight fit formed by the annular flange can, on the one hand, prevent the sealing pin from axially moving during the welding process, which is conducive to ensuring the appearance quality after welding. On the other hand, the sealing gasket can also be kept in a compressed and sealed state at all times, thereby preventing the electrolyte from affecting the welding surface, avoiding hole explosion, and helping to improve the yield rate.

[0007] Furthermore, a side wall of the first step hole has an annular groove arranged in the circumferential direction, and the distance between the annular groove and the second step hole is equal to the distance between the annular ridge and the welding plate.

[0008] In this way, when the sealing column is pressed into the first step hole, the annular ridge will be embedded in the annular groove.

[0009] Furthermore, the end of the sealing column is recessed to form a coaxially arranged groove, and the sealing gasket has a convex column protruding toward the groove, and the convex column is tightly fitted in the groove.

[0010] In this way, the sealing gasket can be better inserted into the first step hole together with the sealing column through the tightly matched protruding column and the groove, making the assembly easier.

[0011] A cylindrical battery, characterized in that it includes a shell that is generally cylindrical and open at one end, the bottom of the shell has a concentrically arranged through hole; a collection plate is arranged in the shell, the middle part of the collection plate has a circular boss protruding toward the through hole, the circular boss cooperates with the through hole and is welded to each other; the middle part of the circular boss has the injection hole that is arranged through, and the injection hole is matched with the sealing nail assembly as described above.

[0012] Furthermore, the confluence plate has confluence areas uniformly distributed along the circumferential direction, and the confluence areas are fan-shaped as a whole and are recessed in a direction away from the circular boss.

[0013] Furthermore, the thickness of the busbar area is smaller than the thickness of the busbar plate.

[0014] Furthermore, a through-going lower liquid hole is provided between two adjacent confluence areas, and the lower liquid hole radially extends into a strip shape along the confluence plate.

[0015] Furthermore, the edge of the busbar has a flange folded away from the circular boss, the flange is tapered as a whole, and has grooves uniformly distributed along the circumferential direction.

[0016] In this way, the conical flange facilitates the automatic centering of the core and the busbar after welding, which facilitates automated manufacturing and improves assembly efficiency. The grooves on the flange can avoid wrinkles and improve the quality of the flange molding.

[0017] In summary, the sealing nail assembly and cylindrical battery of the present invention have the advantages of reasonable structure, being able to avoid the influence of electrolyte on the welding surface, and being conducive to improving the yield rate, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the cross-sectional structure of the bottom of a cylindrical battery.

[0019] Figure 2 It is a schematic diagram of the cross-sectional structure of the sealing nail assembly.

[0020] Figure 3 It is a schematic diagram of the cross-sectional structure of the injection hole.

[0021] Figure 4 It is a structural diagram of the busbar. DETAILED DESCRIPTION

[0022] The utility model is further described in detail below in conjunction with the embodiments.

[0023] When implementing: Figure 1 to Figure 3 As shown, a cylindrical battery comprises a shell 4 which is cylindrical in shape and open at one end, wherein the bottom of the shell 4 has a through hole arranged concentrically; a busbar 5 is arranged in the shell 4, wherein the middle part of the busbar 5 has a circular boss 51 protruding toward the through hole, wherein the circular boss 51 cooperates with the through hole and is welded to the through hole; the middle part of the circular boss 51 has the injection hole 1 which is arranged through, wherein the injection hole 1 is sealed with a sealing nail 2; the outer end of the injection hole 1 has a first step hole 11 and a second step hole 12 which are arranged in sequence from the inside to the outside, wherein the first step hole 11, the second step hole 12, the first step hole 11 and the injection hole 1 are straight The diameter of the sealing nail 2 decreases successively; the sealing nail 2 includes a welding plate 21 matching the second step hole 12, the middle part of the welding plate 21 has a sealing column 22 formed by coaxial protrusion, the diameter of the sealing column 22 matches the diameter of the first step hole 11, and the end of the sealing column 22 is provided with a sealing gasket 3, the length of the sealing column 22 matches the depth of the first step hole 11, so that the sealing gasket 3 can be sealed between the sealing column 22 and the end face of the first step hole 11; the outer circumferential surface of the sealing column 22 is provided with a protruding annular ridge 23 in the circumferential direction, and the annular ridge 23 is tightly fitted on the first step hole 11. The end of the sealing column 22 is recessed to form a coaxial groove 24, and the sealing gasket 3 has a convex column protruding toward the groove 24, and the convex column is tightly fitted in the groove 24.

[0024] In this way, the sealing gasket can be better inserted into the first step hole together with the sealing column through the tightly matched protruding column and the groove, making the assembly easier.

[0025] The side wall of the first stepped hole 11 has an annular groove 13 arranged circumferentially, and the distance between the annular groove 13 and the second stepped hole 12 is equal to the distance between the annular ridge 23 and the welding plate 21. When the sealing column is pressed into the first stepped hole, the annular ridge will be embedded in the annular groove.

[0026] like Figure 4 As shown, the confluence plate 5 has a confluence area 52 uniformly distributed along the circumferential direction, and the confluence area 52 is fan-shaped as a whole, and is recessed in the direction away from the circular boss 51, and the thickness of the confluence area 52 is less than the thickness of the confluence plate 5. A lower liquid hole 53 is provided through-through between two adjacent confluence areas 52, and the lower liquid hole 53 extends radially along the confluence plate 5 into a strip shape. The edge of the confluence plate 5 has a flange 54 folded away from the circular boss 51, and the flange 54 is conical as a whole, and has grooves uniformly distributed along the circumferential direction. In this way, the conical flange facilitates the automatic centering of the winding core and the confluence plate into the shell after welding, which facilitates automated manufacturing and improves assembly efficiency. The grooves on the flange can avoid wrinkles and improve the quality of flange molding.

[0027] With the above structure, since a sealing gasket is provided, after the sealing column is pressed into the first step hole, the sealing gasket can be sealed between the sealing column and the first step hole. At the same time, the sealing column is tightly matched with the first step hole through the annular flange, thereby preventing the sealing column from moving under the reverse elastic action of the sealing gasket, and ensuring that the sealing gasket is always in a sealed state. In this way, the tight fit formed by the annular flange can, on the one hand, prevent the sealing pin from axially moving during the welding process, which is conducive to ensuring the appearance quality after welding. On the other hand, the sealing gasket can also be kept in a compressed and sealed state at all times, thereby preventing the electrolyte from affecting the welding surface, avoiding hole explosion, and helping to improve the yield rate.

[0028] 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 pin assembly, comprising a liquid injection hole (1) provided on a housing or a cover plate and a sealing pin (2) sealingly fitted on the liquid injection hole (1); characterized in that: The outer end of the injection hole (1) comprises a first step hole (11) and a second step hole (12) which are arranged in sequence from the inside to the outside, and the diameters of the first step hole (11), the second step hole (12), the first step hole (11) and the injection hole (1) are successively smaller; the sealing pin (2) comprises a welding plate (21) which matches the second step hole (12), and the middle part of the welding plate (21) comprises a sealing column (22) which is coaxially protruded, and the diameter of the sealing column (22) matches the diameter of the first step hole (11); a sealing gasket (3) is arranged at the end of the sealing column (22), and the length of the sealing column (22) matches the depth of the first step hole (11), so that the sealing gasket (3) can be sealingly fitted between the sealing column (22) and the end surface of the first step hole (11); an annular convex ridge (23) which is protruded is arranged on the outer circumferential surface of the sealing column (22) along the circumferential direction, and the annular convex ridge (23) is tightly fitted on the first step hole (11).

2. The sealing nail assembly according to claim 1, characterized in that: The side wall of the first step hole (11) has an annular groove (13) arranged in the circumferential direction, and the distance between the annular groove (13) and the second step hole (12) is equal to the distance between the annular ridge (23) and the welding plate (21).

3. The sealing nail assembly according to claim 1, characterized in that: The end of the sealing column (22) is recessed to form a coaxially arranged groove (24), and the sealing pad (3) has a convex column protruding toward the groove (24), and the convex column is tightly fitted in the groove (24).

4. A cylindrical battery, characterized in that: The invention comprises a shell (4) which is cylindrical in shape as a whole and open at one end, wherein the bottom of the shell (4) has a through hole arranged concentrically; a collector plate (5) is arranged inside the shell (4), wherein the middle part of the collector plate (5) has a circular boss (51) protruding toward the through hole, wherein the circular boss (51) cooperates with the through hole and is welded to the through hole; the middle part of the circular boss (51) has the injection hole (1) which is arranged through, and the injection hole (1) is cooperated with the sealing nail assembly according to any one of claims 1 to 3.

5. The cylindrical battery according to claim 4, characterized in that: The confluence plate (5) has confluence areas (52) uniformly distributed along the circumferential direction, and the confluence areas (52) are fan-shaped as a whole and are recessed in a direction away from the circular boss (51).

6. The cylindrical battery according to claim 5, characterized in that: The thickness of the busbar area (52) is smaller than the thickness of the busbar plate (5).

7. The cylindrical battery according to claim 5, characterized in that: A through-going lower liquid hole (53) is provided between two adjacent confluence areas (52), and the lower liquid hole (53) extends radially along the confluence plate (5) into a strip shape.

8. The cylindrical battery according to claim 5, characterized in that: The edge of the busbar (5) has a flange (54) that is folded away from the circular boss (51); the flange (54) is tapered as a whole; and the flange (54) has grooves that are evenly distributed along the circumference.

Images