Secondary battery and manufacturing method of the same

Abstract

A secondary battery which reduces production cost and improves productivity by excluding the process of attaching an insulating washer and, instead, insulating a cap plate by forming an UV-curing insulation layer on an external surface of the cap plate after sealing the electrolyte inlet.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a cross-sectional view of the upper end of a secondary battery of the related art;

FIG. 2 is a cross-sectional view of the upper end of a secondary battery according to aspects of the present invention; and

FIG. 3 is a process flow chart of a secondary battery according to aspects of the present invention.

Claims

1. A secondary battery, comprising: an electrode assembly including a positive electrode plate, a separator, and a negative electrode plate;a can to contain the electrode assembly;a cap plate connected to an upper opening portion of the can and including a terminal opening and an electrolyte inlet;an electrode terminal extending through the terminal opening;a gasket disposed between the electrode terminal and the cap plate to insulate the electrode terminal from the cap plate;a plug to seal the electrolyte inlet of the cap plate; andan insulation layer formed of one insulating material disposed on the external surface of the cap plate and the plug.

2. The secondary battery as claimed in claim 1: wherein the insulation layer includes a UV-cured coating layer.

3. The secondary battery as claimed in claim 1: wherein the insulation layer includes a photo-curing resin.

4. A method of fabricating a secondary battery, the method comprising: constructing an electrode assembly and placing the electrode assembly in a can;forming a cap assembly having an electrolyte inlet therethrough;affixing the cap assembly to an upper opening of the can;injecting an electrolyte through the electrolyte inlet of the cap assembly;sealing the electrolyte inlet with a plug; andforming an insulation layer to cover both the plug and an external surface of the cap assembly.

5. The method of fabricating as claimed in claim 4: wherein the insulation layer includes a UV-cured coating.

6. The method of fabricating as claimed in claim 4: wherein the insulation layer includes a photo-hardening resin.

7. The secondary battery of claim 1, wherein the insulation layer electrically insulates the external surface of the cap plate and the plug.

8. The secondary battery of claim 1, wherein the insulating material crosslinks in response to application of electromagnetic radiation.

9. The secondary battery of claim 1, wherein the insulating material is a polymer or a sclerosing paint.

10. The secondary battery of claim 1, wherein the insulating material is sprayable onto the cap plate and the plug.

11. The secondary battery of claim 1, wherein the insulating material crosslinks at a low temperature.

12. The secondary battery of claim 1, wherein the insulating material crosslinks quickly.

13. The secondary battery of claim 1, wherein the insulating material resists pollution.

14. The method of claim 4, further comprising: applying an amount of radiation to the insulation layer to crosslink the insulation layer.

15. The method of claim 4, wherein the insulation layer is formed of one material.

16. The method of claim 4, wherein the insulation layer is formed by spraying a material to cover both the plug and an external surface of the cap assembly.

17. The method of claim 14, wherein the insulation layer is formed of a UV-crosslinking polymer.

18. The method of claim 17, wherein the radiation applied to the insulation layer is UV radiation.

19. A secondary battery, comprising: a cap assembly with an electrolyte inlet therethrough;a plug to seal the electrolyte inlet; anda UV-crosslinked insulation layer,wherein the UV-crosslinked insulation layer is formed on an external surface of the cap assembly and an external surface of the plug.

20. A secondary battery, comprising: a cap assembly with an electrolyte inlet therethrough; anda UV-crosslinked insulation layer,wherein the UV-crosslinked insulation layer is formed on an external surface of the cap assembly.