Patent ID: 6423294
Filing Date: 2002-07-23
Classification: C01G,C01P,H01M,Y02E

Abstract:
A method of preparing a lithium manganese oxide with a spinel structure and having the formula: Li1+X&it;Mn2-Y&it;Mm11&it;Mm22&it;â€¦&it;â€ƒ&it;Mmkk&it;O4+Zwherein:M1, M2, . . . Mk are cations different than lithium or manganese selected from the group consisting of alkaline earth metals, transition metals, B, Al, Si, Ga and Ge; X, Y, m1, m2, . . . mk, each have a value greater than or equal to 0 and less than or equal to 0.2; Z has a value greater than or equal to âˆ’0.1 and less than or equal to 0.2; and X, Y, m1, m2, . . . mk are selected to satisfy the equation: Y=X+m1+m2+. . . +mk said method comprising the step of:calcining a mixture comprising: at least one highly crystalline manganese oxide selected from the group consisting of Mn2O3 and Mn3O4, said manganese oxide having a specific area of less than 2.0 m2/g and a low porosity such that the pore volume of pores having a mean radius of less than âˆ’1 micron in said manganese oxide is no more than 20% of the total pore volume of said manganese oxide; and at least one lithium source compound; in at least one firing step at a temperature greater than or equal to about 400Â° C. and less than or equal to about 900Â° C. to form the lithium manganese oxide spinel compound.