Gas Evolution in Rotating Electrochemical Cells under Reduced and Normal Gravity Conditions

Electrochemical experiments in microgravity are essential for the optimum design of advanced life support systems and power storage systems in space. In the absence of gravity, the evolved gas bubbles will clog the electrode and slow the reaction. Here, a rotating cell concept is introduced as a plan for improving mass transfer and bubble removal in a microgravity environment. A primary experimental study of bubble behavior in rotating water electrolysis cells has been done in reduced gravity through KC-135 parabolic flight. The results show that the cell resistance decreases with increasing rotation rate. Without rotation, the bubbles stick on the electrode surface during reduced gravity period, thus, the cell efficiency degrades. Mass transfer enhanced by bubble generation is investigated in ground-based work at high rotation rate of test cells, so that gravitational effects are minimized.