Electrode Comprising Active Material Layer Having Double-Layered Structure, and Secondary Battery Comprising Same

An electrode for a secondary battery comprises: a current collector; a lower active material layer formed on at least one side of the current collector; and an upper active material layer formed on the lower active material layer. The lower active material layer comprises a first lithium iron phosphate active material, a lithium nickel oxide active material, and a needle-type conductive material. The upper active material layer comprises a second lithium iron phosphate active material and sphere-type conductive material. A ratio of a content of a sum of the first lithium iron phosphate material and the second lithium iron phosphate active material to a content of the lithium nickel oxide active material is in a weight ratio range of from 55 to 70:30 to 45. A total average loading amount of the upper and lower active material layers is in a range of from 300 mg/25 cmto 900 mg/25 cm.