Protons exchange membrane fuel cells (PEMFC) are sensitive to hydrogen and air pollutants. Thisstudy is focused on the impact of carbon monoxide (CO) and hydrogen sulfide (H2S) which are twomajor impurities of hydrogen. A combined experimental and modeling approach has been followed.The experimental part consisted in studying the effect of the concentration of individual pollutants andmixtures, and the effect of catalyst loading, for different operating modes. This work has highlighted animpact on both electrodes (anode and cathode) due to a heterogeneous distribution of the pollutantson the anodic surface area and to a deactivation of the opposite cathodic surface area. Furthermore,in the case of H2S poisoning, this study has shown that the cell voltage can reach a quasi-steadystate, in galvanostatic mode, which had never been highlighted in the literature.In the multi-scales modeling approach, a coupling of the electrochemistry and fluidics as well as thedevelopment of new modules of the model have allowed improving the description of the physicochemicalphenomena. As a consequence, the model simulates a fuel cell in real operating conditions,including the kinetics of platinum poisoning by CO and H2S.Finally, experimental data and simulated data were compared and they showed satisfactory anduseful results for the understanding of the impact of H2 impurities.
