A review of current developments in non-aqueous redox flow batteries: characterization of their membranes for design perspective

Room temperature ionic liquid electrolytes for redox flow batteries

“…Using a series of aprotic imidazolium-based RTILs, we demonstrate significant differences in the voltammetry of V(acac) 3 , Cr(acac) 3 and Mn(acac) 3 .…”

“…While most RFBs contain aqueous electrolytes (common systems include the allvanadium, bromine-polysulfide, and zinc-bromine systems [2]), their energy and power densities are limited as they must operate within the potential region where water is stable (<1.23 V) [3]. Organic electrolytes often have wider potential windows than that of water and, consequently, there is a lot of interest in high energy density, organic RFB systems and systems based on Ru [4], V [5], Mn [6], and Cr [7] complexes have been reported.…”

“…Organic electrolytes often have wider potential windows than that of water and, consequently, there is a lot of interest in high energy density, organic RFB systems and systems based on Ru [4], V [5], Mn [6], and Cr [7] complexes have been reported. In a similar approach to that used in the popular aqueous all-vanadium RFBs [8], the same chemical species is often used on each side of non-aqueous RFBs, mitigating the effects of transfer of redox species between compartments and increasing the coulombic efficiency [3].…”

“…A couple of studies involved using RTILs as supporting electrolytes in non-aqueous, all- Oxidation and reduction peaks associated with the Fe 2+/3+ redox couple were observed and the reaction was electrochemically quasi-reversible. To the best of our knowledge, and despite the opportunities offered both by pure RTIL electrolytes and metal acac salts to RFB technology, RFBs based on soluble V(acac) 3 , Mn(acac) 3 and Cr(acac) 3 (which are very promising for use on organic solvent-based cells [3]) and pure RTIL solvents have not been reported.…”

“…We describe here an investigation of the electrochemistry of Mn(acac) 3 , Cr(acac) 3 , and V(acac) 3 in RTILs. Using a series of aprotic imidazolium-based RTILs, we demonstrate significant differences in the voltammetry of V(acac) 3 , Cr(acac) 3 and Mn(acac) 3 .…”