An emergency lighting device for controlling a lighting means includes an energy store, such as a battery or an accumulator, a charging circuit for the energy store having connections for an AC voltage (alternating voltage), the charging circuit has a potential isolation element, a potentially isolated clocked converter supplied from the energy store and having a switch, preferably a flyback converter. The converter can be supplied only by the energy store, a control circuit for controlling the switch, and a supply path from the secondary side of the converter to connections for the lighting means.