Experimental analysis of a PEM fuel cell performance at variable load with anodic exhaust management optimization

In this paper an investigation on the performance of a commercial Proton Exchange Membrane (PEM) fuel cell, installed at the laboratory of the University of Bologna, is carried out, taking into account the anodic exhaust management and its effects on the flooding phenomenon. To address the problem of flooding, it is necessary to run periodically the purge process of the Fuel Fell (FC). Indeed, in this study the periodic anodic purge process in dead-end mode has been investigated. This operation is performed by opening a particular control valve, the Outlet Purge Valve (OPV), located along the anodic exhaust line. The purge process has been analyzed at different FC power output levels. For each FC power level the optimized behavior of the FC operation was found, by regulating the time of flooding. The aim of this analysis is to optimize the purge process to reduce the amount of hydrogen discharged with water, in order to increase the FC efficiency. An investigation on the benefits in terms of fuel utilization factor and costs, resulting from optimization of the FC purge process, is shown in the paper.