LITHIUM BATTERY AND PREPARATION METHOD THEREOF

A lithium battery includes an electrode group stack i including a plurality of positive electrodes and one or more negative electrodes , wherein the plurality of positive electrodes includes a first and a second positive electrode, the first positive electrode being an inner layer, the second positive electrode being the outermost layer, and the first positive electrode including a first positive current collector and a first positive active material layer, wherein the first positive active material layer is on both surfaces of the first positive current collector, wherein the second positive electrode includes a second positive current collector, a second positive active material layer, and an interlayer between the second positive current collector and the second positive active material layer, the second positive current collector including a first surface and a second surface on opposite sides of the second positive current collector, wherein the first surface faces the inner layer.