| 摘要 |
A secondary battery is provided to prevent the occurrence of bubbles of an electrolyte and reinforce a welding portion when a circumference of an electrolyte injection hole stopper welds. A secondary battery includes: an electrode assembly obtained by laminating and winding a positive electrode plate with a positive electrode tap, a negative electrode plate with a negative electrode tap, and a separator; a can(200) of which one end is opened and which accommodates the electrode assembly; and a cap assembly of which the upside has an electrolyte injection hole, and which comprises a cap plate(310) that closes the opening of the can, and an electrolyte injection hole stopper(312) that seals the electrolyte injection hole. The whole upside of the electrolyte injection hole stopper is molten, the upper circumference of the electrolyte injection hole is molten, and the molten upside of the electrolyte injection hole stopper and the molten circumference of the electrolyte injection hole are coupled to form a closed passage high-speed revolving type laser welding part(314). |
