Patent ID: 7998613
Filing Date: 2011-08-16
Classification: H01M,Y02E

Abstract:
1. A lithium ion secondary battery, comprising: a can having a space defined therein while being opened at an upper portion thereof, and a flange extended outwardly from an upper end of the can, the can having a two-stage step formed on one side wall thereof, in such a manner that the can has a first lower surface, a first side wall extended upwardly from the first lower surface, a second lower surface located higher than the first lower surface and extending outwardly from the first side wall, and a second side wall extended upwardly from the second lower surface; a cap having a contact surface facing the flange of the can and the cap not being inserted into the can; an electrode assembly located on the first lower surface and including a cathode plate and an anode plate; and a protruded terminal connected to one of the cathode plate and the anode plate, and protruding through only the second lower surface to an outside of the can and located between the first side wall and the second side wall and located inwardly from the second side wall toward the defined space, wherein an outer surface of the flange of the can is micro-arc welded to an outer surface of the cap, thereby forming a sealed container and the protruded terminal is only located at the second lower surface of the can where the two-stage step is formed so that a cooling jig can be installed and contacted to the sealed container such that only the outer surface of the flange of the can and the outer surface of the cap are exposed to the outside.