Systematic and rapid screening for the redox shuttle inhibitors in lithium-sulfur batteries

High performance liquid chromatography (HPLC) can be used to systematically and rapidly screen the potential additives for the inhibition of the polysulfide shuttle effect in a Li-S battery. The method is proven effective by investigating the 18 compounds which were reported in the literature as redox shuttle inhibitors for Li-S batteries. The change of the polysulfide ions from being exposed to 18 different redox shuttle inhibition additives was qualitatively and quantitatively determined. The changes of polysulfide species and elemental sulfur were successfully used to study the inhibition effect of the additives in Li-S batteries. It was confirmed that nitrate salts under the same concentration showed the best inhibition effect for the polysulfide shuttle reaction. However even in the electrolyte with nitrate additives, the shuttle reactions between Li metal and polysulfides (and elemental sulfur) are still notable, and thus the search for a better polysulfide shuttle inhibitor is ongoing and critical for improving the electrochemical performance of Li-S batteries.