Investigation of Liquid Water Formation in PEMFC By Direct Simulation and Operando X-Ray Computed Tomography

Abstract

Direct modeling-based Lattice Boltzmann Method (LBM) [1-3] combined with in-operando X-ray computed tomography (CT) is used to investigate the liquid water formation in the porous layers of polymer electrolyte membrane fuel cell (PEMFC). Studies of the local saturation of liquid water, heat transfer, species transport, and electrochemical kinetics with platinum metal group (PGM) and PGM-free catalyst layers are explored under different cell operating conditions. The detailed structure of dry (i.e., GDL, MPL, and CL) and wet samples (i.e., liquid saturation) used in this study were obtained by in-operando X-ray CT, which allows for accurate visualization of water transport in operating PEMFCs. The overall predictions were compared and validated with experimental data [4, 5]. Figure 1 shows the comparison examination of liquid formation on the detailed structure of porous layer with PGM and PGM-free catalyst layers. The results reveal that the liquid water evolution/saturation inside the GDL samples are different when the cell operating conditions and transport properties are changed. More results will be presented and discussed.