Elucidating the increased ohmic resistances in zero-gap alkaline water electrolysis

This is the metadata for the research paper "Elucidating the increased ohmic resistances in zero-gap alkaline water electrolysis". In this study we elucidate the possible reasons for the increased ohmic resistances in zero-gap alkaline water electrolysis. We critically assess the methodology for estimating the ohmic resistance of zero-gap electrolyzers as reported in literature. In order to monitor variations in ohmic resistance during zero-gap alkaline electrolysis, we employ electrochemical impedance spectroscopy (EIS) at both low and high current densities. Both 2- and 4-terminal configurations are used to address additional contact or cable resistance. Furthermore, we evaluate the diaphragm wettability and the bubble behavior both outside and inside the diaphragm using a photographic method to better understand the possible role of bubbles. Our intention is that these findings will help to open the way for electrolyzers with reduced ohmic resistance, enabling efficient operation...