A method for black starting a power supply device is disclosed, wherein the power supply device includes at least one bidirectional inverter having an AC-side connection for a grid and a battery connected to the DC side of the bidirectional inverter. The method includes operating an activation device of the power supply device so that the activation device applies a voltage to a control line of the battery to place the battery into an operating state, wherein the voltage provided by the activation device is provided by an auxiliary battery. The method also includes putting the bidirectional inverter into an operating state after the voltage provided by the auxiliary battery is applied to the control line.