Optimization of PEM Fuel Cell Operation with High-purity Hydrogen Produced by a Membrane Reactor

An innovative micro-cogeneration system (m-CHP) based on membrane reformer and polymer electrolyte membrane fuel cell (PEMFC) is developed within the FluidCELL project. The purity of the hydrogen separated by the membrane reformer can decrease over time, due to membrane/sealing degradation, therefore a methanator is adopted to prevent CO poisoning of the fuel cell. This paper investigates the optimal control strategies of a polymer electrolyte membrane (PEM) fuel cell at different hydrogen purities by using a detailed 1D model, including the CO poisoning on the anode Pt-Ru catalyst, and calibrated against experimental data. Simulation results show that the system is able to work also with low-purity hydrogen thanks to the effectiveness of the methanator, the resistance to CO poisoning of the Pt-Ru anode catalyst, the small voltage drop due to inert gases accumulation in the anode recirculation loop: at 0.3 A cm(-2) as current density, the stack efficiency is always above 60% even when the membranes selectivity drops to 5 10(2).