METHOD FOR ACTIVATING SECONDARY BATTERY

The present invention relates to a method for activating a secondary battery. The present invention comprises: a primary charging step of charging a secondary battery including a positive electrode, a negative electrode, a separator, and an electrolyte; a room temperature-aging step of storing, at a room temperature, the secondary battery that has undergone the primary charging step; and a high temperature-aging step of storing, at a high temperature, the secondary battery that has undergone the room temperature-aging step, wherein charging/discharging is performed by alternately applying + current and − current to the secondary battery at the end of the primary charging step. The method for activating a secondary battery according to the present invention includes alternately applying + current and − current to the secondary battery at the end of the primary charging step to stabilize an SEI film, thereby shortening a following-up aging time.