Operando neutron imaging of an alkaline electrolysis cell for mapping gas distributions

Optimizing hydrogen and oxygen transport within porous electrodes is essential for improving the efficiency of industrial alkaline electrolyzers. In this study, we utilize operando dynamic neutron radiographic measurements to investigate gas distributions and bubble dynamics within an alkaline electrolysis cell. Porous nickel foam was used as cathode and anode in the zero-gap cell configuration to replicate the gas evolution conditions occurring in industrial settings. Our results indicate that approximately 50 % of hydrogen and oxygen is generated within the innermost quarters of both the cathode and anode at the lower section of the electrolysis cell. Additionally, the findings imply that 4–8 % of the volume within the electrode compartments remains occupied by immobilized gas bubbles. These findings demonstrate the potential of neutron imaging as a powerful technique for quantitative mapping of gas volumes within electrolyzer systems. • Operando neutron radiography for mapping hydrogen and oxygen gas distributions. • Neutron imaging of zero-gap alkaline water electrolysis cell. • Immobilized gas in nickel foam electrodes. • Quantitative neutron imaging of hydrogen and oxygen gas bubbles.