A numerical study of the polarization effect of liquid water in the gas diffusion layer of a proton exchange membrane fuel cell

Abstract

To improve the efficiency and lifetime of proton exchange membrane fuel cells, a deeper understanding of the physical and chemical factors affecting the water transport within the fuel cell is required. A factor that is often neglected in corresponding investigations is the polarization of the liquid water molecules in the unevenly distributed electric field. Therefore, in this paper, the effect of polarization on the transport of liquid water in the gas diffusion layers (GDL) is studied. Thereto, numerical simulations are conducted using the structural and physical properties of TORAY TGP-H-060 carbon paper GDL. The simulation findings indicate that the polarization effect has no substantial impact on the shape of liquid water droplets in the GDL. Nonetheless, polarization significantly lowers the internal pressure of the water droplets needed to penetrate the GDL.