Patent attributes
A secondary battery including a can for receiving an electrolyte and an electrode assembly including first and second electrode plates and a cap assembly including a cap plate covering an upper portion of the can. An electrode terminal connected to one of the first and second electrode plates is inserted into a center portion of the cap plate. A safety vent is formed at a first side of the cap plate and an electrode lead wire is connected to an upper surface of the electrode terminal to connect the electrode terminal to an external terminal. A washer is installed on an upper surface of the cap assembly in order to insulate the cap plate from the electrode lead wire and has an exposure part for exposing the safety part allowing the location of the safety vent to be noted without disassembly of the secondary battery.