NOVELTY - An electrochemical conversion system comprises a first and second masses of hydrogen absorbent material in a housing; a first electrode, a proton conductive membrane, and a second electrode between a first and second masses of hydrogen absorbent material; and a supply of hydrogen.    USE - For producing electricity.    ADVANTAGE - The electrochemical conversion system of the invention does not require a continuous source of reactant. It does not require an electrolyte which may become plugged over time. The system may be operated at relatively low temperatures.    DETAILED DESCRIPTION - An electrochemical conversion system comprises a first mass of hydrogen absorbent material (17); a second mass of hydrogen absorbent material (18) spaced from the first mass; a first electrode (20); a second electrode (21); a proton conductive membrane (22) between the two electrodes; a housing (11) containing the masses of hydrogen absorbent material, the electrodes, and the membrane; and a supply of hydrogen. The electrodes and the membrane are operably between the masses of hydrogen absorbent material. The first and second masses of hydrogen absorbent material are in fluid communication with each other through the electrodes and through the proton conductive membrane. The hydrogen may be desorbed by one mass of hydrogen absorbent material and absorbed by the other mass while passing past and reacting with the electrodes and the proton conductive membrane to cause an electric potential difference between the electrodes. An INDEPENDENT CLAIM is also included for a method of producing electricity, which comprises flowing hydrogen through an electric conversion cell. The hydrogen protons are produced from the oxidation of hydrogen gas passing past one of the electrodes. The hydrogen flow is induced by a pressure differential across the cell resulting from the release of hydrogen from a mass of metal hydride material. An electric current is induced through a load coupled to the electrodes.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of an electrochemical conversion system of the invention.    Housing (11)    Mass of hydrogen absorbent material (17, 18)    Electrode (20, 21)    Proton conductive membrane (22)    Heat transfer system (25)