Electrochemical characterization of hydrogen pump with internal humidifier and dead-end anode channel

Hydrogen gas is compressed with a new electrochemical pump, where internal humidifier is built in, and dead-end at anode is considered for a practical situation. Both the voltage and current efficiency of the hydrogen pump is evaluated experimentally. The pump is operated up to 2 MPaG under the temperature condition of 293 and 333 K. The voltage efficiency indicates nearly 50% at most and the maximum current efficiency is 96%. Overpotentials inherently involved in the pump are discussed with electrochemical impedance spectroscopy.