Hydrogen and proton exchange membrane fuel cells for clean road transportation

In this paper the main issues related to the working of hydrogen fuel cells and their utilization in the transportation field are presented and discussed, starting from the experimental analysis of dynamic performance of a laboratory fuel cell system based on a 20 kWe H2/air proton exchange membrane stack. The experiments were carried out on successive load steps characterized by low reactant relative pressures (15–50 kPa) and stack temperature of 310–350 K. The effect of air flow rate, hydrogen purge and membrane humidification strategy on stack output voltage was evaluated evidencing the role of different sub-systems in stack management (for reactant feeding, stack cooling, membrane humidification) and their effect on efficiency losses of the overall system. The results presented in this paper provide experimental indications about potentialities of hydrogen fuel cell systems as clean electric energy generators for automotive applications.