The multi-layered electrode is expected to exhibit improved flow battery performance due to its variable flow and electrochemical properties that can be locally optimized in different layers. The porosity combination and the thickness of layers with different porosities will affect the reaction rate and the uniformity of the reactant distribution. Although a variety of models have been developed to guide the design of the electrode microstructure, how to mathematically optimize the properties of the electrode with multi-layered carbon paper sheets, remains unknown. In the present study, the authors devise a 3D, multi-physical vanadium redox flow battery model with the multi-layered electrode, and put forward a 1D analytical model for optimizing porosity distribution of multi-layered electrode in the redox flow cell. The optimization results based on the 3D simulations are presented.
Keywords redox flow battery, VRFB, porous material electrode, multi-layered electrode, porosity distribution , analytical model