Effect of Flow Channel Shape and Operating Temperature on the Performance of a Proton Exchange Membrane Electrolyzer Cell

Proton exchange membrane electrolyzer cells (PEMECs) are considered to be an environmentally friendly system for producing high-purity hydrogen through water electrolysis. However, they require optimal configurations and operating conditions for energy and cost-effective practical applications. In this study, four different types of flow paths inside a PEMEC were proposed, namely, parallel, single-channel, four-channel, and parallel grid, and the effect of the flow path shape inside the PEMEC on hydrogen evolution reaction was examined. In addition, the optimal operating temperature was determined via electrochemical experiments. The experimental results reveal that the parallel grid flow field yielded the highest current density of 118.04 mA/cm2 and hydrogen production at a volume flow rate of 6.6 mL/min owing to a relatively higher electrochemical surface area of 1.11657 cm2 at the optimum operating temperature of 40 °C compared with other flow fields. Computational fluid dynamics analysis results confirmed that at 40 °C the parallel grid flow field has an advantageous path shape for electrolyte distribution inside the PEMEC, and consequently, the appropriate flow rate facilitates the transport of reactants and products. The findings of this study can be used as a reference for PEMEC research in terms of the selection of a suitable flow field geometry and temperature for PEMECs operating under different conditions.