The electrolyte for a lithium battery includes a non-aqueous organic
solvent, a lithium salt, and an additive of the following Formula 1:
##STR00001## wherein, X is O or S,Y.sub.1, Y.sub.2, and Y.sub.3 are the
same or different from each other and selected from the group consisting
of O, S, CR.sub.2, and NR, where here R is H, a halogen, or an alkyl
having a carbon number of less than or equal to 8, or neighboring alkyl
groups are combined to each other to form a cycle or hetero cycle,
andR.sub.a to R.sub.d are the same or different from each other and
selected from H, a halogen, an alkoxy group having a carbon number of
less than or equal to 8, or an unsaturated or saturated alkyl group
having a carbon number of less than or equal to 8, or neighboring alkyl
groups are combined to each other to form a cycle or hetero cycle.