Rechargeable lithium battery

A rechargeable lithium battery comprising:

• an electrolyte comprising a non-aqueous organic solvent comprising an ethylene carbonate-based compound, a pyrocarbonate-based additive, and a lithium salt, wherein the pyrocarbonate additive is present in the electrolyte in an amount ranging from about 0.01 to about 5 wt % based on the total weight of the electrolyte, the pyrocarbonate-based additive being selected from the group consisting of dimethylpyrocarbonate, diethyl pyrocarbonate, methylethyl pyrocarbonate, methylpropyl pyrocarbonate, methylbutyl pyrocarbonate, methyldecyl pyrocarbonate, ethyldodecyl pyrocarbonate, ethylcetyl pyrocarbonate, di-2-ethylhexyl pyrocarbonate, di-tert-butyl pyrocarbonate, and combinations thereof;
• a negative electrode comprising a negative active material comprising a crystalline-based carbon core and an amorphous-based carbon shell surrounding the crystalline-based carbon core, and the amorphous-based carbon shell consists essentially of an amorphous-based carbonaceous material;
• and
• a positive electrode comprising a positive active material.