Modeling the Vanadium Oxygen Fuel Cell

F.T. Wandschneider[1], M. Küttinger[1], P. Fischer[1], K. Pinkwart[1], J. Tübke[1], H. Nirschl[2]
[1]Fraunhofer-Institute for Chemical Technology, Pfinztal, Germany
[2]Karlsruhe Institute for Technology, Karlsruhe, Germany

A two-dimensional stationary model of a vanadium oxygen fuel cell is developed in COMSOL Multiphysics®. This energy storage device combines a vanadium flow battery anode and an oxygen fuel cell cathode. The oxygen reduction reaction generates additional water, leading to a degradation of the catalyst performance over time. A logistic function is introduced to the Butler-Volmer equation in order to model this degradation. The model can then be used in a semi-transient way, thus saving computational time over a fully transient model.