PEM electrolysis simulation and validation

To meet the ever-growing demand for polymer electrolyte membrane (PEM) electrolyzers to operate at higher current densities, higher pressures and higher temperatures, a zero dimensional simulation was developed to optimize operating conditions and cell geometries. The model presented was focused on capturing the performance of an electrolyzer operating at higher current densities ranging from 2-6 A/cm(2). This entails focusing more on the mass transport and ohmic losses (both proton and electron transport) that dominate under these conditions. A design tool was developed to optimize operational and geometrical parameters of a PEM electrolyzer. Models with a strong focus on ohmic losses and prediction of membrane proton transport were combined to improve the prediction of the ohmic losses. These are particularly important when operating at high current densities due to the linear dependence ohmic losses have with current density. In this research a polymer electrolyte membrane (PEM) electrolysis model was developed to include a water supply shortage mass transport loss. The mass transport losses depend on concentrations, flow rates, porous transport layer morphologies, temperature and pressure. The simulation results are validated with a single cell PEM electrolyzer operating without water circulation on the cathode (hydrogen) side.