Hydrogen system and method of operation

A method for providing hydrogen, comprising:

• feeding a gas comprising hydrogen to an anode side of a first electrochemical cell stack, feeding a liquid comprising water and a water-compatible redox compound in an oxidant form;
• applying a voltage to the first electrochemical cell stack to ionize hydrogen ions at the anode side and transport them to the cathode side of the first electrochemical cell stack, and to reduce the water-compatible redox compound to a reductant form comprising hydrogen acquired at the cathode side of the first electrochemical cell stack;
• transporting the liquid comprising water and the water-compatible redox compound in reductant form to an anode side of a second electrochemical cell stack;
• applying a voltage to the second electrochemical cell stack to oxidize the water-compatible redox compound to the oxidant form and release hydrogen, and to transport ions of the released hydrogen through a proton exchange membrane to form hydrogen on a cathode side of the second electrochemical cell stack;
• and
• providing hydrogen from the cathode side of the second electrochemical cell stack.