Patent ID: 7074382

Claim:
A method of preparing a compound having a substantially single phase, hexagonal layered crystal structure, being substantially free of localized cubic spinel-like structural phases and having no diffraction peaks at a smalller scattering angle than the diffraction peak corresponding to Miller indices ( 003 ) in its powder x-ray diffraction pattern, the method comprising the steps of synthesizing a lithium metal oxide having the formula Li Î± M Î² A Î³ O 2 , wherein M is one or more transition metals, A is one or more dopants having an average oxidation state N such that +2.5â‰¦Nâ‰¦+3.5, 0.90â‰¦Î±â‰¦1.10, and Î²+Î³=1, at a temperature of at least 600Â° C.; and cooling the lithium metal oxide to room temperature at a rate of between 8Â° C./min and 140Â° C./min; wherein if M is Co in the lithium metal oxide, said synthesizing step comprises synthesizing the lithium metal oxide from a cobalt source compound selected from the group consisting of Co 3 O 4 and Co(OH) 2.