Synergistic binary catholyte design for enhanced electrochemical performance in membraneless hybrid flow batteries

Abstract

A hydroquinone (HQ)/1,2-dihydroxybenzene-3,5-disulfonic acid (Tiron) binary catholyte system is developed for membraneless zinc hybrid flow batteries, leveraging sequential redox reactions with complementary potentials to enhance energy density and electrochemical kinetics. The HQ–Tiron system achieves an energy density of 21.4 W h L⁻¹ and a peak power density of 102.3 mW cm⁻².