A secondary battery according to an embodiment of the present disclosure includes an external terminal electrically connecting a charge collector disposed inside a battery case with a terminal, a first part electrically connected to the charge collector, a second part electrically connected to the terminal, a first connection part electrically connecting the first part with the second part, and a second connection part electrically connecting the first part with the second part, the second connection part being different from the first connection part. The first connection part is ruptured when a displacement of the displacement part toward the outside of the battery case is transferred to the first connection part, and the second connection part becomes nonconductive when a temperature of the second connection part reaches a predefined temperature.