High performance zinc-bromine redox flow batteries: Role of various carbon felts and cell configurations

Optimization of the cell configuration utilizing various carbon felts for obtaining better performance in zincbromine redox flow battery (ZBRFB) system is reported. It is clearly observed that the reaction kinetics of both Zn and Br are enhanced when used in different cell configurations with carbon felts. Redox flow cells having carbon felts on both half-cells showed improved performance thanthe other cell configurations tested in the present study. Further, Rayon based carbon felt is evaluated as an electrode on both sides. It is noted that the Rayon carbon felt based cell exhibited good performance in terms of coulombic (96.26%), voltaic (83%) and energy efficiency (79.4%) at a current density of 20 mA.cm(-2). In addition to that, Rayon felt based system showed good performance even at 40 mA.cm(-2) (3250 mW h. l(-1)) which indicates the significance of the flow cell configuration on the overall cell performance.