Manganese oxide, lithium manganese complex oxide and cobalt-coated lithium manganese complex oxide, and preparation processes thereof

摘要

A manganese oxide which has a calcium or/and magnesium content of 0.01 to 2.50 mol % based on the moles of manganese, a lithium manganese complex oxide using the manganese oxide, and a cobalt-coated lithium manganese complex oxide are disclosed. These provide a particularly high discharge capacity and are useful for the improvement of cycle characteristics of a secondary battery as an active material of a positive electrode for a secondary battery with a nonaqueous electrolyte.