Impact of humidification by cathode exhaust gases recirculation on a PEMFC system for automotive applications
Résumé
Reactant gases humidification, in most PEM fuel cell systems, is traditionally implementedto ensure both stack durability and superior performance. A cathode exhaust gases recirculationarchitecture allows to decrease the system volume compared to the passive humidifiers,which are classically used. Incorrect water management being responsible forirreversible degradations, a control of relative humidity at stack inlet thanks to the recirculationcould be of great interest to limit their impact. In this work, investigations onperformance and stability are performed during operation in recirculation mode, from thecell scale to the system scale. It was observed that high to medium recirculation ratios wereable to stabilize and homogenize the cells voltages along the stack but performance wasreduced due to oxygen dilution by nitrogen. Besides, large relative humidity ranges wereachieved at stack inlet, which can vary from 25 to 85% and could be able to follow automotivedynamics.
Domaines
Génie des procédés
Origine : Fichiers produits par l'(les) auteur(s)