Optimization of purge cycle for dead-ended anode fuel cell operation

Abstract

Dead-Ended Anode (DEA) operation of Proton Exchange Membrane Fuel Cells (PEMFCs) yields a system with lower complexity and the potential to reduce system cost as fewer external components are required. Optimization of the purge interval and cycle duration, for a given operating power, can increase the fuel cell efficiency which depends on three interrelated objectives, namely, the hydrogen loss during the purge, the average voltage output between the purges, and the voltage decrease due to the carbon corrosion caused by hydrogen starvation over the lifetime of the DEA operation.In advancing past results, this paper shows how the purge cycle can be optimized for better efficiency in DEA operation by considering the impact of carbon corrosion. For this optimization, a model capturing the liquid water and nitrogen accumulation in the anode is needed to accurately describe the evolution of corrosion rate and the amount of hydrogen wasted during the purge. The optimization process is first defining a target range of purge intervals based on the physical constraints of the actuator and the model-based prediction of the species concentration distributions. The search of optima is performed then by scanning the target domain to quantify the trade-off between wasted hydrogen and reducing the corrosion rate over a long time horizon.