Lead-modified graphite felt electrode with improved VO2+/VO2+ electrochemical…

Graphite felt is disadvantageous of lower electrochemical reaction activity, which is improved by introducing catalysts. Especially, cheaper materials and simple fabrication are popular for reducing cost. In this work, electrodeposited-lead electrode is proposed for improving electrochemical reaction activity of VO2+/VO2+ couple as well as charge-discharge performance of the battery. Experiment platform is established for vanadium redox flow battery. Cyclic voltammetry and charge-discharge performance measurements are carried out. Electron scanning microscope (SEM) is employed to investigate the surface morphology of electrode. Results show that peak potential difference (ΔE+) and peak current ratio (Ia+/Ic+) with electrodeposited-lead electrode is 103.7 mV lower and 0.249 lower than that with untreated electrode for VO2+/VO2+ electrochemical reaction. Electron scanning microscope images exhibit that lead particles are adhered extensively on carbon fiber of electrodeposited-lead electrode, which improves electrochemical activity of VO2+/VO2+ couple. Energy efficiency of the battery with electrodeposited-lead electrode in positive side is higher than that with untreated electrode by 8.5% at 60 mAcm−2. Electrodeposited-lead electrode exhibits higher activity to VO2+/VO2+ reaction and brings about higher energy efficiency of battery. This work provides a suitable electrode for vanadium redox flow battery.