POSITIVE ACTIVE MATERIAL CONTAINING COMPOSITE METAL OXIDE FOR MAGNESIUM RECHARGEABLE BATTERIES AND MAGNESIUM RECHARGEABLE BATTERIES COMPRISING THE SAME

摘要

The present invention relates to a composite oxide-based cathode active material for a magnesium secondary battery represented by Mg_yMA_2O_7-zC_z and a magnesium secondary battery comprising the same. The cathode active material for a magnesium secondary battery of the present invention has a new structure in which polyanions form a framework and magnesium ions are chemically or electrochemically inserted or separated to/from a channel or a tunnel existing between the framework formed by the polyanions so as to not only improve electroconductivity by facilitating the movement of magnesium ions among particles but also express relatively high stability, a long lifespan and excellent thermal properties in comparison with an existing magnesium secondary battery of which the crystalline structure collapses during the movement of the magnesium ions.