Dynamics and control of membrane hydration in a PEMFC

The subject of water management is a key issue in the design and operation of Polymer Electrolyte Membrane Fuel Cells (PEMFC). In this paper we present a dynamic model central to understanding the water management and flooding issue. First we consider membrane hydration and show how the interplay between electro-osmotic drag and back-diffusion determine ionic conductivity. The model is then used to identify appropriate manipulated variables for controlling the location and shape of the hydration profile within the membrane.