Delayed Start

Materials discovery is key to the continued advancement of redox flow batteries (RFBs), and renewed interest in this energy storage technology has led to growth and diversification of the community. While new entrants introduce a range of innovative new approaches, inconsistent understanding of the electrochemical principles that are central to determining the efficacy of candidate RFB electrolytes can lead to mischaracterization of new materials, challenging comparative analyses across the field. This tutorial introduces foundational electrochemical methods (i.e., macroelectrode, microelectrode, and rotating disk electrode voltammetry) in the context of RFBs, discussing how to elicit thermodynamic, kinetic, and transport properties from redox electrolytes. Specifically, we will examine proper experimental methodology, data interpretation, and considerations for translating such characteristics to cell performance. Finally, we will describe emerging methods for establishing stability and cyclability in candidate electrolytes, using bulk electrolysis and symmetric cells as stepping stones toward full cell diagnostics.