The redox flow battery (RFB) is one of the most promising large-scale energy storage technologies for the massive utilization of intermittent renewables especially wind and solar energy. This work presents. ••A redox flow battery using low-cost iron and lead redox materials is p. The massive utilization of intermittent renewable energy sources especially wind and solar energy urgently needs large-scale energy storage devices to achieve uninterrupted an. 2.1. Electrolyte preparationThe premixed iron and lead electrolyte was prepared by dissolving the lead monoxide (Nacalai Tesque) and iron powder into the diluted methanes. 3.1. Iron-lead redox systemFig. 2a shows the CV curves of the Fe(II)/Fe(III) and Pb/Pb(II) redox couples in the mixed-reactant electrolyte at the different scan rat. In summary, a RFB utilizing cheap and abundant iron/lead redox materials has been proposed and demonstrated. The CV test shows that Fe(II)/Fe(III) and Pb/Pb(II) redox couples ex.