Rechargeable lithium battery

Abstract

A rechargeable lithium battery includes an electrode laminate including a positive electrode including a positive current collector and a positive active material layer disposed on the positive current collector; a negative electrode including a negative current collector, a negative active material layer disposed on the negative current collector, and a negative electrode functional layer disposed on the negative active material layer; and a separator, wherein the electrode laminate has a ratio (L/W) of a height (L), which is a length in a protruding direction of an electrode terminal, relative to a width (W), which is perpendicular to the protruding direction of the electrode terminal and parallel to the laminate surface, is about 1.1 to about 2.3, the positive active material layer includes a first positive active material including 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 including a compound represented by Chemical Formula 1, the negative electrode functional layer includes flake-shaped polyethylene particles, and an operation voltage is greater than or equal to about 4.3 V.LiFeMPO  [Chemical Formula 1] In Chemical Formula 1, 0.90≤a≤1.8, 0≤x1≤0.7, and M is Mn, Co, Ni, or a combination thereof.