Experimental evaluation of state-of-the-art electrode and separator materials under advanced alkaline water electrolysis operation conditions

Operating alkaline water electrolysis (AWE) at enhanced temperatures (at or above 100 °C) and higher pressures can improve process efficiency due to a reduction of overvoltages. However, experimental research at these advanced AWE operation conditions is scarce. This study aims to fill this gap by presenting comprehensive experimental results using an AWE cell equipped with state-of-the-art electrodes from De Nora and separators from Agfa-Gevaert that were evaluated in a test rig with a wide range of the operational parameters, including temperatures from 80 to 130 °C, pressures from 2 to 24 bar and flow rates from 1.5 to 2.85 l/min. The temperature increase yielded the strongest improvement in cell performance, followed by the pressure with a moderate and the flow rate with a minimal impact on the reduction of the cell voltage. The best cell performance was achieved at 130 °C, 15 bar and 1.5 l/min, reaching 1.7 A/cm 2 at a cell voltage of 1.99 V.