TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Components: The gas-receiving chamber comprises an input (11) for receiving gaseous stream of impure hydrogen, and an output (15) for venting an outlet stream containing contaminants from the impure hydrogen stream and hydrogen not absorbed by the gas diffusion anode. The outlet stream is fed into a hydrogen separator for separation into a hydrogen stream containing major portion of hydrogen and a waste stream containing contaminants. The hydrogen stream is fed into the impure hydrogen stream, and the waste stream is vented to the atmosphere or collected. The gas diffusion anode comprises an active material layer containing hydrogen storage alloy and a material catalytic towards the dissociation of molecular hydrogen into atomic hydrogen; a gas diffusion layer to distribute the impure hydrogen stream across the active material layer; and current collector grid(s), e.g. metal sheet, expanded metal, foil, wire mesh, and/or screen. The gas diffusion anode is electrically connected with the power source to supplement the power source with an electrical current produced from the oxidation of absorbed hydrogen at the electrolyte interface during operation. The electrolytic cathode comprises a substrate with a material catalytic towards the decomposition of water to form hydrogen and hydroxyl ions. The substrate is metal sheet, expanded metal, foil, wire mesh, and/or screen.    TECHNOLOGY FOCUS - METALLURGY - Preferred Materials: The hydrogen storage alloy is rare-earth alloy, Misch metal alloy, zirconium and/or titanium alloy, and/or magnesium/nickel alloy. The catalytic material of the cathode comprises a host matrix of nickel, molybdenum, and/or cobalt; and modifying element(s), e.g. titanium, molybdenum, tantalum, zinc, chromium, niobium, manganese, iron, vanadium, copper, strontium, silicon, lanthanum, cerium, oxygen, cobalt, aluminum, carbon, ruthenium, Misch metal, and/or Raney Nickel. The substrate is formed from nickel, steel, titanium, graphite, and/or copper.