A novel method for determining forcing drivers for total water flow in PEM fuel cells including electro-osmotic drag, back diffusion, and single- and two-phase thermal osmosis

Abstract

Heat and water management are essential for successful for PEM fuel cell operation, the goal being optimal fuel cell hydration to maximize ionic conductivity. Overhydration can lead to flooding on the cathode side. In experimentation on PEM fuel cells, total water transfer across the membrane is a result of simultaneous fluid drivers present in the experiment, including voltage, chemical potential, thermal and pressure gradients, and is measured indirectly with a high degree of precision.