The synergy between the redox flow batteries and other battery chemistries offers the opportunity towards highly modular electrical energy storage systems. As an emerging battery technology based on lithium chemistry, the Li-redox flow batteries inherit and step further towards the smart features of other battery technologies. Our research effort focuses on the design rationale, fundamentals and characterization of Li-redox flow batteries from a chemistry and material perspective, with particular emphasis on the development of redox-active organic compounds as high-energy liquid electrodes.