SECONDARY BATTERY AND METHOD OF FABRICATING THE SAME

Abstract

A secondary battery includes an electrode assembly and a can having an opening at one end of the can. The electrode assembly is housed in the can. A cap plate seals the opening. The cap plate includes an electrolyte injection hole. An electrode terminal is coupled to the cap plate electrical connecting the electrode terminal and the electrode assembly. A gasket is located between the electrode terminal and the cap plate to insulate the electrode terminal from the cap plate. A plug seals the electrolyte injection hole, the plug being coated with an elastic film.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a portion of a conventional secondary battery.

FIGS. 2A and 2B are sectional views of an electrolyte injection hole of a conventional secondary battery before and after the electrolyte injection hole is sealed by an aluminum ball, respectively.

FIG. 3 is exploded perspective view of an exemplary embodiment of a secondary battery in accordance with the present invention.

FIG. 4 is a sectional view of an exemplary embodiment of a plug in accordance with the present invention.

FIG. 5 is a sectional view of a sealed electrolyte injection hole using the plug of FIG. 4.

FIG. 6 is a sectional view of a portion of an exemplary secondary battery in accordance with the present invention.

FIG. 7 is a sectional view of an electrolyte injection hole of the secondary battery of the FIG. 6.

FIG. 8 is a flow chart of an exemplary manufacturing method of a secondary battery in accordance with the present invention.

FIGS. 9A, 9B, 9C, 9D and 9E are sectional views of an electrolyte injection hole being sealed by the manufacturing method of FIG. 8.

Claims

1. A secondary battery comprising; an electrode assembly;a can having an opening at one end of the can, the can housing the electrode assembly;a cap plate sealing the opening, the cap plate having an electrolyte injection hole for inserting electrolyte into the can;an electrode terminal coupled to the cap plate to provide an electrical connection between the electrode terminal and the electrode assembly;a gasket located between the electrode terminal and the cap plate for insulating the electrode terminal from the cap plate; anda plug for sealing the electrolyte injection hole, the plug being coated with an elastic film.

2. The secondary battery of claim 1, wherein the elastic film is a resin.

3. The secondary battery of claim 2, wherein the resin is a hardening resin.

4. The secondary battery of claim 3, wherein the hardening resin is an epoxy resin.

5. The secondary battery of claim 1, wherein the plug is a ball or a pin.

6. The secondary battery of claim 5, wherein, the plug is made from material selected from the group of aluminum, aluminum alloy, and stainless steel.

7. A secondary battery comprising; an electrode assembly;a can having an opening at one end of the can, the can housing the electrode assembly;a cap plate for sealing the opening, the cap plate including an electrolyte injection hole for inserting electrolyte into the can; anda plug for sealing the electrolyte injection hole;wherein an elastic film is located between the electrolyte injection hole and the plug.

8. The secondary battery of claim 7, wherein the electrolyte injection hole has a stepped configuration such that an upper hole portion of the stepped configuration for inputting electrolyte into the can has a diameter larger than a diameter of a lower hole portion adjacent to the upper hole portion; andwherein the elastic film coats wall surfaces of the upper hole portion.

9. The secondary battery of claim 7, wherein the elastic film is fluorine resin or polyolefin resin.

10. The secondary battery of claim 7, wherein the elastic film is fluorine rubber, Butadiend rubber, or Isobutylene-Isoprene rubber.

11. A method of manufacturing a secondary battery, the secondary battery including a can having an opening at one end of the can, the method comprising; providing an electrode assembly;inserting the electrode assembly into the can through the opening;sealing the opening with a cap plate, the cap plate having an electrolyte injection hole for inserting electrolyte into the can,coating the electrolyte injection hole with an elastic film;injecting electrolyte into the can through the electrolyte injection hole; andcompressing a plug to seal the electrolyte injection hole such that the plug contacts the elastic film.

12. The method of claim 11, wherein the electrolyte injection hole further comprises a stepped configuration such that an upper hole portion of the stepped configuration for inputting electrolyte into the can has a diameter larger than a diameter of a lower hole portion adjacent to the upper hole portion, and wherein coating the electrolyte injection hole with an elastic film further comprises: preparing a loader with a liquid solvent;aiming the loader at the upper hole portion;injecting the liquid solvent into the upper hole portion while moving the loader along a diameter of the electrolyte injection hole; anddrying the liquid solvent to form the elastic film.

13. A method of manufacturing a secondary battery, the secondary battery including a can having an opening at one end of the can, the method comprising; providing an electrode assembly;inserting the electrode assembly into the can through the opening;sealing the opening with a cap plate, the cap plate having an electrolyte injection hole for inserting electrolyte into the can,injecting electrolyte into the can through the electrolyte injection hole; andcompressing a plug to seal the electrolyte injection hole;wherein the plug includes a resin covering the surface of the plug.

14. The method of claim 13, wherein the resin is a hardening resin.

15. The method of claim 14, wherein the hardening resin is an epoxy resin.

16. The method of claim 13, wherein the plug is made from material selected from the group of aluminum, aluminum alloy and stainless steel.