Is 3-methyl-2-oxazolidinone a suitable solvent for lithium-ion batteries?

Abstract

3-Methyl-2-oxazolidinone (MeOx) has been mixed to ethylene carbonate (EC) or dimethyl carbonate (DMC) in presence of lithium tetrafluoroborate (LiBF 4) or lithium hexafluorophosphate (LiPF 6) for use as electrolyte in lithium batteries. The optimized electrolytes in term of conductivity and viscosity are MeOx:EC, x(MeOx) = 0.5 and MeOx:DMC, x(MeOx) = 0.4 in presence of LiBF 4 (1 M) or LiPF 6 (1 M). MeOx:EC electrolytes have a better thermal stability than MeOx:DMC electrolytes but the low wettability of the Celgard separator by MeOx:EC prevents its use in lithium batteries. No lithium insertion–deinsertion occurs when LiPF 6 is used as salt in MeOx-based electrolytes. MeOx:DMC, x(MeOx) = 0.4 + LiBF 4 (1 M) exhibits a good cycling ability at a graphite electrode but all the investigated electrolytes containing MeOx have a low stability in oxidation at a lithium cobalt oxide electrode (Li x CoO 2).