Provided is a secondary battery pack including a plurality of secondary battery modules including a plurality of secondary battery cells stacked in parallel to each other in a vertical direction, a cover, and a switch installed at an upper side of the one end in the horizontal direction of the cover, a housing, a Power Relay Assembly (PRA) including a relay electrically connected to the secondary battery cells and switches, for transmitting charging power supplied from the outside to the secondary battery cells when the relay is in a close state and changing the relay to an open state when the switch is pushed according to pressure applied to an upper side from a lower surface of the cover, and a Battery Management System (BMS) for controlling the Power Relay Assembly (PRA).