Patent ID: 7056486

Claim:
A method for preparing lithium manganese complex oxide with a spinel structure comprising: a) providing a spinel Li 1+x Mn 2−x−y M y O 4 (0.01≦x≦0.1,0≦y≦0.5, and M is one or more metal atoms other than lithium and manganese) intercalation compound used as a core powder; b) providing a mixture of a lithium compound and a manganese compound without solvent, wherein a ratio of the lithium compound to the manganese compound is from 0.5:1.0 to 2.0:1.0 based on a mole ratio of Li and Mn; c) coating the mixture of step b) without solvent on the spinel Li 1+x Mn 2−x−y M y O 4 intercalation compound of step a); and d) calcining coated spinel compound prepared in step c) to form a new phase of spinel structure on the core.