Sizing Supercapacitor for Direct Hybridization with Polymer Electrolyte Membrane Fuel Cell

An efficient solution to accommodate fuel cell (FC) systems to the dynamic loads met in transport applications consists in hybridizing the FC with a storage device, such as batteries or supercapacitors. Among all possible configurations, direct hybridization with supercapacitors offers substantial advantages in terms of mass, volume, reliability, efficiency and cost. The present article investigates the influence of supercapacitor sizing on FC efficiency. For this purpose, a FC electrical model based on mass and charge transport equations, associated with a supercapacitor electrical model including porosity effects, are used to compute the hybrid source responses to an urban dynamic load profile. Simulated results, which demonstrate how increasing supercapacitor can enhance FC efficiency, are validated by experimental tests carried out on a 100 cm2 single FC fed with dry hydrogen and humidified air.