Investigation of the Effect of Gas Diffusion Layer Thickness on the PEM Fuel Cell Performance

The structure of the gas diffusion layer influences cell performance because it also affects the passage of reaction gases and electrons. In this study, the effect of the thickness of the gas diffusion layer on the cell performance for the singlecelled PEM fuel cell was investigated by numerically modelling. In order to investigate the effect of the gas diffusion layer on the performance of the PEM fuel cell, a stable single-phase and three-dimensional model was established. The effect of the gas diffusion layer thickness on the current density and the amount of power obtained is examined. By analysing the gas diffusion layer thickness under different operating conditions; the current density at different cell potentials and the amount of power obtained were determined. In addition, the changes in the current density with respect to temperature, pressure and air flow rate are given as graphs for the different gas diffusion layer thicknesses. The highest current density was found to be 1.794 A/cm2, where the gas diffusion layer thickness was 0.2 mm and the cell potential was 0.4 V. In addition, the results obtained at high cell potentials are close to each other.