A rechargeable lithium battery includes a positive electrode having a positive current collector and a positive active material layer at least partially disposed on the positive current collector, wherein the positive active material layer includes a first positive active material having at least one of a composite oxide of a metal selected from cobalt, manganese, nickel, and a combination thereof and lithium, and a second positive active material having a compound represented by Chemical Formula 1 as defined herein, and a negative electrode having a negative current collector, a negative active material layer at least partially disposed on the negative current collector, and a negative electrode functional layer having generally flake-shaped polyethylene particles at least partially disposed on the negative active material layer.