CAP ASSEMBLY HAVING SAFETY VENT WITH NOTCH

The present invention relates to a cap assembly which is installed to the open upper part of a can which has a structure of forming a cylindrical can in an electrode assembly. It includes a safety vent which has a notch which is broken when the withstand voltage of a battery increases, an upper cap of an upward protrusion type which is connected to it along the outer surface of the safety vent, and a current blocking member which is attached to the lower end of the safety vent and blocks a current when the withstand voltage of a battery increases. The safety vent includes a first bending part which is bent from the outer surface to a lower part, a slope part which is extended from the first bending part to the lower part, and a second bending part which is horizontally bent from the slope part to a center part. The notch is formed in the first bending part of the first bending part and the second bending part.