This study uses the finite element technique to analyse a multi-dimensional model for a polyelectrolyte membrane fuel cell at high working temperature. A computational fluid dynamics (CFD) technique implements and solves this model. In addition, the membrane’s thickness, and catalyst layer’s thickness parameters have been studied. Membrane thickness is varied from to and the length of the fuel cell from to. The performance of the fuel cell was studied, analysed, and discussed for each case using the polarization curves and output power. The results indicate that the performance of fuel cells is enhanced by a thinner membrane than a thicker one with an increase in loading. The performance is approximated at light loads. Furthermore, the concentration of water at the cathode side of the fuel cell is highly affected by the change in fuel cell length more than the thickness of the membrane. Comparative analysis with prior research demonstrates strong agreement with our consequences.