Patent ID: 8557447

Claim:
A rechargeable lithium battery comprising: a negative electrode including a non-carbon-based negative active material, wherein the non-carbon-based negative electrode comprises at least one selected from the group consisting of Si, silicon oxide (SiO x , 0<X>2), Si-M (M is at least one metal selected from the group consisting of Al, Sn, Ag, Fe, Bi, Zn, In, Ge, Pb, and Ti), SnO 2 , Sn, and combinations thereof; a positive electrode including a positive active material that reversibly intercalates and deintercalates lithium ions; and an electrolyte consisting essentially of: a non-aqueous organic solvent that includes ethylene carbonate in an amount of 20 volume % or less based on a total volume of the non-aqueous organic solvent, a lithium salt including LiPF 6 , a first additive represented by the following Formula 1 and a second additive that is LiB(C 2 O 4 ) 2 in an amount of about 0.1 to about 5 parts by weight based on 100 parts by weight of the electrolyte, wherein the electrolyte has a viscosity of 3.02 cP or less: wherein, in the above Formula 1, R 1 and R 2 are independently selected from the group consisting of hydrogen, a halogen, a cyano (CN), a nitro (NO 2 ), and a C1 to C5 fluoroalkyl, provided that at least one of R 1 and R 2 is selected from the group consisting of a halogen, a cyano (CN), a nitro (NO 2 ), and a C1 to C5 fluoroalkyl.