Theoretical study of an influence of the materials parameters on the performance of a polymer electrolyte fuel cell

The paper presents a systematic investigation of the influence of alterations in the values of the polymer electrolyte membrane, catalyst layers and gas diffusion layer characteristics on the performance of a PEMFC. The individual influences of 25 material properties were tested using CFD simulation on a single channel fuel cell. The calculations of PEMFC performance were conducted by increasing and decreasing the values of each tested parameter, and comparing the results to a reference case. The dependencies of the current
density on the following quantities were analysed in detail: 1) the cell potential, 2) the power density, 3) the membrane over-potential, 4) the mean water concentration in the PEM, 5) the relative humidity at the interface CCL/GDL, and 6) the total water flux through the PEM.
The results showed that the variations in the conductivities and thicknesses of the PEM and GDL, as well as variations in GDL porosity, led to significant changes in fuel cell performance. The characteristics of the anode catalyst layer had little influence on fuel cell behaviour. Increasing the thickness and exchange
current density of the cathode catalyst layer increased the current densities, while the reduction of the transfer coefficient decreased fuel cell performance.