Adaptation and Application of a Polarisation Curve Test Protocol for a Commercial Pem Electrolyser on Cell and Stack Level

The present study aims to develop a test protocol based on the literature for electrochemical characterisation of a polymerelectrolyte membrane (PEM) electrolysis commercial stack using polarisation curves. For this, a 1-kW water electrolysis test standwith integrated temperature control and measurement systems was built around the stack. Afterwards, the stack performancewas characterised under different operating pressure and temperature conditions by using polarisation curves. A measurement protocolwas developed based on the literature. To ensure the reproducibility of the results, two rounds of experiments were performed.The experiments were carried out at temperatures between 20 and 60 °C and pressures up to 15 bar. The results show distinct regionsin the polarisation curves related to the activation and ohmic overvoltage. The effect of temperature and pressure on the performanceis shown and analysed. The performance of single cells in the stack is also measured. The stack polarisation curves are comparedwith those in the literature, which gives an understanding of the materials used in electrodes and types of membranes.