Lithium manganese-based composite oxide and method for preparing the same

摘要

The present invention provides a lithium manganese-based composite oxide represented by the compositional formula: Li 1+x (Mn 1-m-n Fe m Ti n ) 1-x O 2 , wherein 0 < x < 1/3, 0 ‰ m ‰ 0.75, 0.01 ‰ n ‰ 0.75, and 0.01 ‰ m+n <1, and comprising a crystal phase of layered rock-salt type structure. The composite oxide is capable of maintaining an average discharge voltage of 3 V or more over long charge/discharge cycles. The composite oxide can be prepared using lower-cost starting materials, and exhibits improved charge/discharge characteristics over conventional low-cost positive electrode materials.