Cap assembly and secondary battery using the same

摘要

Cap assembly, coupled to an open end of a battery can free from a beading portion, includes a top cap at an uppermost portion in a protrusive form forming a cathode terminal, a safety element below the top cap contacting the top cap, a safety vent contacting the safety element, a gasket surrounding outer circumferences of top cap, the safety element and vent, a cover surrounding the gasket so the top cap, safety element and vent adhere to each other, and a welding member at an upper portion of the cover having an outer end protruding more outwards than the outer end of the cover placed on the open end of the battery can, the welding member having a first notch at an upper surface thereof, protruding more than the outer end of the cover, and welded to the open end of the battery can where first notch is formed.

主权项

1. A cap assembly for a secondary battery, coupled to an open end of a battery can free from a beading portion, the cap assembly comprising:
a top cap disposed on an uppermost portion in a protrusive form to form a cathode terminal; a safety element disposed below the top cap to contact the top cap; a safety vent disposed to contact the safety element; a gasket surrounding outer circumferences of the top cap, the safety element and the safety vent; a cover surrounding the gasket so that the top cap, the safety element and the safety vent closely adhere to each other; and a welding member disposed at an upper portion of the cover and having an outer end located to protrude more outwards than the outer end of the cover so as to be placed on the open end of the battery can, the welding member having a first notch formed at an upper surface thereof, which protrudes more than the outer end of the cover, and being welded to the open end of the battery can at a portion where the first notch is formed.