SECONDARY BATTERY

The present disclosure relates to a secondary battery, which includes a cap assembly (13) including a cap plate (131) provided with an electrode lead-out hole (131a), an electrode terminal (132) adapted to cover the electrode lead-out hole (131a), a sealing ring (133) disposed between the cap plate (131) and the electrode terminal (132), and a lower insulating member (134) including a base portion (134a) and a protruding portion (134b) connected to each other, wherein the base portion (134a) is located at a lower side of the cap plate (131) and has a thickness of 0.01 mm to 10 cm, and the protruding portion (134b) is at least partially located in the electrode lead-out hole (131a); a current collecting member (14) including a body portion (141) and an extending portion (142) connected to each other, wherein the body portion (141) is located below the base portion (134a) of the lower insulating member (134), and the extending portion (142) is configured to extend into the electrode lead-out hole (131a) and is connected to the electrode terminal (132); and a support member (15) disposed between the body portion (141) of the current collecting member (14) and the base portion (134a) of the lower insulating member (134). The secondary battery according to the embodiments of the present disclosure can limit the lower insulating member via the support member and thus can effectively prevent the lower insulating member from moving downward.