The present invention relates to an electrochemical device. The device features an anode constructed of materials such that the device can be chemically recharged. In addition, the device is capable of switching between operating as a fuel cell or as a battery. In certain aspects of the invention, the device includes a liquid anode and is capable of operating at a temperature of less than 1000.degree. C. Other aspects feature a control system and a fuel delivery system for the electrochemical system.