A numerical evaluation of felt electrodes in a vanadium redox flow battery

The charge and mass transport phenomena of the different types of commercial electrodes such as KFD 2.5, GFD 2.5, GFD 4.6 and GFA 6 in a vanadium redox flow battery with the single-cell are presented in this study, comparatively. In order to perform these comparisons, all properties of the four different types of electrodes are applied to the numerical model which validated experimental data. The results indicated that the biggest electrode potential difference between the positive electrode and negative electrode belongs to GFD 4 .6 electrode with 1.20244 V, the smallest difference in the electrode potential belongs to KFD 2.5 electrode with 1.19832 V. Although KFD 2.5 and GFD 2.5 have the same electrode thickness, GFD 2.5 exhibits a better current density variation throughout both positive and negative electrode sides due to its higher electrical conductivity. While the V2+ and V5+ vanadium concentrations remain constant at 300 mol/m(3) for KFD 2.5 and GFD 2.5 electrodes, these concentrations are approximately 310 mol/m(3) for GFD 4.6 and GFA 6 after x/L = 0.5.