Secondary Battery

The present invention relates to a secondary battery. The secondary battery according to the present invention comprises an electrode assembly wherein electrodes and separators are alternatingly stacked, and a battery case in which the electrode assembly is accommodated, where the battery case comprises a first gas pocket on which a first collection space for collecting gases in the battery case is formed, and on which is provided a first exhaust port from which gases in the first collection space are exhausted, and a second gas pocket on which a second collection space for collecting gases exhausted from the first exhaust port is formed, and on which is provided a second exhaust port for outward exhaust of gas in the second collection space.