Probing Multiphysics Interactions in the PEFC Catalyst Layer Using a Coupled Direct Numerical Simulation-Lattice Boltzmann Method (DNS-LBM) Framework

Abstract

The complex dynamics associated with the flooding phenomena in Polymer Electrolyte Fuel Cells (PEFC) need to be appropriately probed in order to facilitate proper water management. In this work, we propose a hybrid Direct Numerical Simulation-Lattice Boltzmann Method (DNS-LBM) framework that enables to investigate such intricate multiphysics coupling. The reaction area passivation and pore blockage which is a consequence of the formation of water as a byproduct from the Oxygen Reduction Reaction (ORR) is implicitly correlated to the geometrical configuration of the catalyst layer microstructure and influences the local electrochemistry leading to mass-transport limitations. In addition, the effect of operating current density on the saturation zones alters the distribution of reaction current within the electrode. This synergistic modeling approach sheds light on the aforementioned mechanisms at the pore-scale and paves the way for detailed understanding of the performance of low Platinum loaded cathode catalyst layers.