This invention described the preparation of a series of compounds selected from the group comprising
tris(1,1,1,3,3,3-hexafluoro-iso-propyl)
phosphate,
tris(perfluoroethyl)
phosphate,
tris(perfluoro-iso-propyl)
phosphate, bis(1,1,1-trifluoroethyl)fluorophosphate, tris(1,1,1-trifluoroethyl)phosphate, hexakis(1,1,1-trifluoroethoxy)
phosphazene, tris(1,1,1-trifluoroethoxy)trifluorophosphazene, hexakis(perfluoro-t-butyl)
phosphazene and tris(perfluoro-t-butyl)phosphate. These compounds may be used as co-solvents, solutes or additives in non-aqueous electrolytes in various electrochemical devices. The inclusion of these compounds in
electrolyte systems can enable rechargeable chemistries at high voltages that are otherwise impossible with state-of-the-art
electrolyte technologies. These compounds are chosen because of their beneficial effect on the interphasial chemistries formed at high potentials, such as 5.0 V class cathodes for new Li
ion chemistries. These compounds may be used in Li
ion battery technology and in any electrochemical device that employs non-aqueous electrolytes for the benefit of
high energy density
resultant from high operating voltages.