Patent ID: 6974486

Claim:
A method of preparing a positive active material for rechargeable lithium batteries, the method comprising the steps of: obtaining a powder from a source material, the source material being selected from the group consisting of Li x MnO 2 , Li x Mn 1-y M y O 2 , Li x Mn 1-y M y O 2-z F z , Li x Mn 1-y M y O 2-z S z , Li x Mn 2 O 4 , Li x Mn 2-y M y O 4 , Li x Mn 2-y M y O 4-z F z , and Li x Mn 2-y M y O 4-z S z , where 0<x<1.5, 0.05≦y≦0.3, z≦1.0 and M is selected from the group consisting of Al, Co, Cr, Mg, Fe and La; and coating the powder with a metallic alkoxide solution to make an alkoxide-coated powder, the metallic alkoxide solution being selected from the group consisting of Mg-Alkoxide and Al-alkoxide; and heat-treating the alkoxide-coated powder such that the alkoxide-coated powder is changed into an oxide-coated powder.