Gas Purge for Switching of Polymer Electrolyte Unitized Reversible Fuel Cell

Unitized reversible fuel cells combine the functionality of a fuel cell and electrolyzer in one unitized device. Gas purge operation is essential for switching from electrolyzer to fuel cell operation at a polymer electrolyte unitized reversible fuel cell. In order to examine the relationships between the spending time and the gas flow rate, a gas purge model is presented. The model considers physical phenomena such as evaporation and diffusion from liquid water in the GDL and the membrane. Experimental data obtained with two cells with different size are also presented. The simulated curves of high frequency resistance versus time are in good agreement with the experimental data.