Multiscale Modeling of PEMFC Using Co-Simulation Approach

Abstract

Enhancement of fuel cell performance at high current densities is essential to improve the overall power density and to reduce the cost of proton exchange membrane fuel cell (PEMFC) systems. Mass transport over-potential is the major barrier to achieving high performance at a high current density. Condensed water, specifically in the gas diffusion layer (GDL), reduces oxygen transport to the oxygen reduction reaction (ORR) area. Experimental investigations of oxygen transport are limited by an inability to resolve the water saturation-dependent properties. The alternative approach to understand and overcome transport resistances, particularly inside the GDL, is to use state-of-the-art mathematical modeling. This work shows the successful development of a multi-scale calculation technique with co-simulation approach that incorporates a detailed structure of each scale dimension for every component of a fuel cell. The flow-field bipolar plates and membrane electrode assembly (MEA) models are calculated using traditional computational fluid dynamics (CFD) method with existing PEMFC model; whereas the detail structured GDLs are numerically predicted by Lattice Bolzmann method (LBM). This technique can be used to develop material and design solutions to improve the mass transport; which is the most critical for high end performance and operational robustness.