Micro-Scale Transport in the Diffusion Media of Polymer Electrolyte Fuel Cells

This paper reports our recent work on the stochastic-model-based reconstruction of the gas diffusion layer (GDL) of PEFCs and direct numerical simulation and presented the pore-level transport within GDLs of polymer electrolyte fuel cell (PEFC). The carbon-paper-based GDL is modeled as a stack of thin sections with each section described by planar 2D random line tessellations which are further dilated to three dimensions. The reconstruction of the GDL structure is based on given GDL data provided by scanning electron microscopy (SEM) images. Based on the stochastically constructed digital GDL, we further conduct the DNS of the coupled transport processes, including gas flow and species transport, electronic current conduction, and heat transfer. Results indicate remarkable distinction in tortuosities of gas diffusion passage and solid matrix. The numerical tool can be applied to investigate the GDL microstructure and internal pore-level transport in PEFCs.