BUTTON-TYPE SECONDARY BATTERY

A button-type secondary battery includes an electrode assembly; a lower can into which the electrode assembly is disposed; and an upper can configured to cover an opening of an upper end of the lower can. A beading part recessed inward is disposed at an upper portion of the lower can. The upper end of the lower can disposed above the beading part has a bent shape and configured to surround an edge end of the upper can so that the upper can and the lower can are coupled to each other.