A reversible electrochemical system includes a first electrode comprising liquid silver metal and a second electrode, said first and second electrodes separated by a oxygen ion-conducting solid electrolyte; a conduit for directing a first reactive material across the second electrode; and a conduit for contacting second reactive material with the first liquid silver electrode, wherein the cell is capable of steam electrolysis when the polarity of the electrodes is selected such that the liquid silver is an anode and the cell is capable of electrical energy generation when the polarity of the electrodes is selected such that the liquid silver is a cathode.