SECONDARY BATTERY HAVING SUPERIOR PRODUCTIVITY AND SAFETY

Disclosed is a secondary battery having a structure in which a jelly-roll having a cathode/separator/anode structure is mounted in a cylindrical battery case, wherein a plate-shaped insulator mounted on the top of the jelly-roll includes a perforated inlet enabling gas discharge and penetration of electrode terminals, and a plurality of fine pores that allow permeation of an electrolyte solution, but do not allow permeation of foreign materials having a size of 100 µm or higher.