Rechargeable lithium battery

A rechargeable lithium battery comprising:

• a positive electrode comprising a positive active material comprising nickel and represented by LiaNibEcGdO2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5 and 0.001≤d≤0.1, E is Co;
• G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or combinations thereof);
• a negative electrode comprising a negative active material comprising a Si-based material and a carbon-based material, the Si-based material being a composite consisting of Si and C, or silicon oxide, or a combination thereof;
• an electrolyte solution comprising:
• a lithium salt, a non-aqueous organic solvent, and an additive;
• the non-aqueous organic solvent comprising a cyclic carbonate and a linear carbonate, the linear carbonate comprising ethylmethyl carbonate and dimethyl carbonate;
• and
• the additive comprising at least one selected from fluoroethylene carbonate, propane sultone, succinonitrile, adiponitrile, or combinations thereof;
• a separator between the positive electrode and the negative electrode, the separator comprising a porous substrate and a coating layer positioned on at least one side of the porous substrate, the coating layer comprising an inorganic compound comprising Al (Aluminum).