A rechargeable lithium battery and a method of preparing the same are described. The rechargeable lithium battery includes a positive electrode including a positive active material; a negative electrode including a negative active material; and a liquid electrolyte including a lithium salt and a non-aqueous organic solvent. A separator is interposed between the negative electrode and positive electrode and includes a support. A fluoro-based polymer layer is positioned on both sides of the support. The positive electrode includes the positive active material in an amount from about 30 to about 70 mg/cm2.