Polytetrafluorethylene effects on liquid water flowing through the gas diffusion layer of polymer electrolyte membrane fuel cells

Abstract

A three-dimensional (3D) lattice Boltzmann model is applied to simulations of the dynamic process of liquid water moving through the gas diffusion layer, processed by covering the fibers with polytetrafluorethylene (PTFE), in polymer electrolyte membrane fuel cells. The PTFE content and two through-plane distribution styles were analyzed regarding their impact on the liquid water's flow behavior. The total saturation curves show that the water's breakthrough times are affected by these two factors. Different characteristic shapes of local saturation curves are observed with different types of PTFE distribution. The dynamic elevation plots of water fronts show that certain PTFE distribution styles can be of advantage to fuel cell efficiency.