Spinel-Structured Lithium Manganese-Based Positive Electrode Active Material, and Positive Electrode and Lithium Secondary Battery Which Include the Positive Electrode Active Material

A spinel-structured lithium manganese-based positive electrode active material includes a lithium manganese oxide represented by Formula 1, and a coating layer which is disposed on a surface of the lithium manganese oxide and includes at least one coating element selected from the group consisting of aluminum, titanium, tungsten, boron, fluorine, phosphorus, magnesium, nickel, cobalt, iron, chromium, vanadium, copper, calcium, zinc, zirconium, niobium, molybdenum, strontium, antimony, bismuth, silicon, and sulfur, and a positive electrode and a lithium secondary battery which include the positive electrode active material, LiMnMOA [Formula 1]