SECONDARY BATTERY AND BATTERY MODULE INCLUDING THE SAME

A secondary battery according to an embodiment of the present invention includes: an electrode assembly; and a pouch-type casing in which the electrode assembly is embedded, the pouch-type casing including upper and lower casings thermally bonded to each other, in which the pouch-type casing includes a sealing part formed along at least a part of an edge of the pouch-type casing and formed by thermally bonding the upper and lower casings, in which electrode leads connected to the electrode assembly protrude from sides of the pouch-type casing, in which the sealing part includes a notch portion formed at any one end of the side from which the electrode leads protrude, and in which the notch portion has a curvature which is recessed toward the inside of the pouch-type casing.