Synthesis, Characterization and Evaluation of Pb Electroplated Carbon felts for Achieving Maximum Efficiency of Fe-Cr Redox Flow Cell

Abstract

To catalyze Cr(III)/Cr(II) redox couple, Pb was used as candidate catalysts. Pb has a remarkable behavior on reduction and oxidation of chromium couple to enhance the performance of Fe-Cr redox flow cell. In the present investigation catalyzed carbon felt substrates were used as electrodes on negative side which were electrochemically plated/ loaded with Pb from 0.05g to 1.2g. The cell comprising 0.8 g Pb loaded felt has shown 100% Chromium reduction efficiency, 98% coulombic efficiency and zero hydrogen gassing at 32oC for 15 cycles of charge and discharge. 5liters of 1.3N FeCl2 in 2N HCl as catholyte, 1.3N CrCl3 in 2N HCl as anolyte containing 0.05N BiCl3 as additive were used as electrolytes. The cell operated with Nafion-117 PFSA membrane. 100 cm2 GFA grade carbon felts with 3mm thickness were utilized as electrodes at a current density of 50 mA/ cm2.