Electrochemical characterisation of Raney nickel electrodes for alkaline water electrolysis: From laboratory to industrial scale
Alise-Valentine Prits, Martin Maide, R. Väli, A. C. Nunes, Peeter Valk, Mairis Bērziņš, Peeter Paaver, Rainer Küngas, Jaak Nerut
Abstract
A Raney nickel electrode is characterised in various electrochemical measurement setups for alkaline electrolysis. Experiments are conducted with a typical laboratory-scale three-electrode setup, two different flow-cell setups and a 10-kW electrolysis stack of 17 cells. In addition to the cell geometry (electrode area ranging from 1 cm 2 to 960 cm 2 ), the varied measurement conditions include temperature (ranging from room temperature to 80 °C), pressure (from 1 atm to 16 atm), electrolyte concentration (from 0.1 M to 30 % wt KOH), and the level of Fe impurities in the electrolyte. It is demonstrated that with an appropriate setup and measurement conditions, it is possible to predict the performance of electrodes at an industrial scale by conducting laboratory-scale experiments. • Commercial electrodes were studied with various alkaline water electrolysis setups. • Fe content, temperature, and setup are key to industrially relevant research data. • Well-designed lab tests can predict the performance of an electrolyser stack. • Setup recommendations for alkaline electrolysis research were outlined.