Modeling the effects of mechanical solicitations and their influence on the power production of a polymer electrolyte membrane fuel cell

Abstract

For the past years, many studies have been conducted to understand and analyze the behavior of fuel cells (FC). In our present work, we study the effects of mechanical solicitations on the physical properties of polymer electrolyte membrane FC. We first analyze the influence of different pressures (applied on graphite or steel bipolar plates (BP)) on the porosity, permeability, and deformation of the gas diffusion layer (GDL) and then we evaluate these local fields of GDL porosity and permeability. Moreover, a new numeric approach based on fluid mechanics is elaborated to study the effects of mechanical compression of the GDL on the performance of the cell through the variation of the local pressure at the GDL/BP interface; it has been shown that this local pressure is no longer uniform but varies locally. Finally, the effects of this compression are incorporated into a multi-physical model that considers the chemical phenomena and the effects of mechanical compression of the FC to correctly simulate and report the polarization and power density curves and to conclude about the performance of the cell.