A drain plug assembly that has particular application for sealing a drain hole in a battery compartment on a vehicle. The plug assembly includes a plug that inserted into the drain hole and a cover covering the plug. The plug assembly also includes a first shape memory alloy (SMA) wire having ends attached to the cover and a middle portion attached to the plug and a second SMA wire having ends attached to the cover and a middle portion attached to the plug. The plug assembly also includes a mechanical hinge attached to the plug and the cover, wherein the first SMA wire is actuated to flip the hinge to position the plug in a closed position to close the drain hole and the second SMA wire is actuated to flip the hinge to position the plug in an open position to open the drain hole.