Adaptation and Validation of a Pore-Network Model for Tracking Water in PEM Fuel Cell Electrodes

Liquid water in PEM fuel cell porous transport layers, also known as gas diffusion layers, has been extensively studied in order to understand how to remove product water and reduce mass trasnport losses. A variety of pore network models and imaging techniques have been developed and successfully used to model water transport in these porous layers. Mass transport losses also occur in the electrodes (catalyst layers) due to water where there is little understanding of how water interacts with the ionomer films and percolates through the pore space. In order to better understand liquid water movement, holdup, and evaporation in catalyst layers a pore network model has been adapted for use on PEM fuel cell electrodes. Network models are built on an abstraction of geometric features. Therefore, ex-situ characterization tests are needed to determine if the abstraction is valid. This talk focuses on the electrode network model development, characterization, and parametric studies examining the interplay between production of heat and water with transport through the catalyst support, pore space and ionomer films.