Addition of weak acids in electrolytes to prevent osmosis in aqueous organic redox flow batteries

Water transfer issues related to unbalanced ionic strengths in aqueous organic redox flow batteries (AORFBs) are often overlooked. In this work, a simple strategy based on the addition of weak acid negolyte was studied prevent osmosis AORFBs. Ferrocyanide [Fe(CN)6]4- and anthraquinone-2,7-disulfonic disodium salt (AQDS) were used as positive negative active materials, respectively, aspartic chosen acid. The well strong bases such KOH, NaOH or LiOH reach complete deprotonation desired pH contributes balancing cations total concentration both compartments. Battery cycling experiments carried out with 0.2 – 0.3 M AQDS 0.4 0.6 [Fe(CN)6]4?. When no used, quickly leading shortage electrolyte observed, while presence volumes remained unchanged during time experiment.