NOVELTY - An electrode consists of current collector to which electrode composition comprising electrode active material, binder and conductive material, is applied. The electrode active material is positive electrode active material and/or negative electrode active material. The positive electrode active material comprises lithium-manganese-containing oxide (I), and negative electrode active material comprises lithium-containing oxide (II). The content of conductive material in electrode composition is 0.1-15% with respect to total weight of electrode composition.    USE - Electrode is used for secondary battery e.g. lithium secondary battery of battery module used in battery pack of device e.g. electric vehicle, hybrid electric vehicle, plug-in hybrid electric vehicle and power storage device (all claimed). Uses include but are not limited to electrical golf cart, electric bicycle, electrical scooter and electric two-wheeled vehicle.    ADVANTAGE - The device obtained using electrode has excellent high-temperature stability, long cycleability and rate characteristics.    DETAILED DESCRIPTION - An electrode consists of current collector to which electrode composition comprising electrode active material, binder and conductive material, is applied. The electrode active material is positive electrode active material and/or negative electrode active material. The positive electrode active material comprises lithium-manganese-containing oxide (Lix-My-Mn2-y-O4-z-Az) (I), and negative electrode active material comprises lithium-containing oxide (LiaM'b-O4-cAc) (II). The content of conductive material in electrode composition is 0.1-15% with respect to total weight of electrode composition, where x is 0.9-1.2, y is more than 0 and less than 2, z is 0 to less than 0.2, M is element chosen from aluminum, magnesium, nickel, cobalt, iron, chromium, vanadium, titanium, copper, boron, calcium, zinc, zirconium, niobium, molybdenum, strontium, antimony, tungsten, titanium and bismuth, A is anion having charge of -1 or -2, b is 0.2-4, a is 0.1-4 and M' is titanium, tin, copper, lead, antimony, zinc, iron, indium, aluminum and zirconium, and c is 0 to less than 0.2.