Oxidatively stable fluorinated sulfone electrolytes for high voltage high energy lithium-ion batteries

New fluorinated sulfones were synthesized and evaluated in high voltage lithium-ion batteries using a LiNi0.5Mn0.3Co0.2O2 (NMC532) cathode. Fluorinated sulfones with an α-trifluoromethyl group exhibit enhanced oxidation stability, reduced viscosity and superior separator wettability as compared to their non-fluorinated counterparts. Their improved performance in high voltage NMC532/graphite cells makes them promising high voltage electrolytes for next generation high voltage high energy lithium-ion batteries.