Feasibility of a Supporting-Salt-Free Nonaqueous Redox Flow Battery Utilizing Ionic Active Materials.
Nonaqueous redox flow batteries (NAqRFBs) are promising devices for grid-scale energy storage, but high projected prices could limit commercial prospects. One route to reduced prices is to minimize or eliminate the expensive supporting salts typically employed in NAqRFBs. Herein, the feasibility of a flow cell operating in the absence of supporting salt by utilizing ionic active species is demonstrated. These ionic species have high conductivities in acetonitrile (12-19 mS cm-1 ) and cycle at 20 mA cm-2 with energy efficiencies (>75 %) comparable to those of state-of-the-art NAqRFBs employing high concentrations of supporting salt. A chemistry-agnostic techno-economic analysis highlights the possible cost savings of minimizing salt content in a NAqRFB. This work offers the first demonstration of a NAqRFB operating without supporting salt. The associated design principles can guide the development of future active species and could make NAqRFBs competitive with their aqueous counterparts.
['Milshtein|Jarrod D|JD|0000-0001-8322-5106', 'Fisher|Sydney L|SL|', 'Breault|Tanya M|TM|', 'Thompson|Levi T|LT|', 'Brushett|Fikile R|FR|0000-0002-7361-6637']
D000097:Acetonitriles D001881:Borates D001888:Boric Acids D004467:Economics D011211:Electric Power Supplies D004573:Electrolytes D004867:Equipment Design D005240:Feasibility Studies D007477:Ions D010084:Oxidation-Reduction
energy storage techno-economic analysis electrochemistry nonaqueous flow batteries redox chemistry