Li[Ni1/3Co1/3Mn1/3]O2-zFz (x=0-0.15) were synthesized via a co-precipitation followed by a high-temperature heat treatment. Though the initial discharge capacities of Li[Ni1/3Co1/3Mn1/3]O2-zFz (x=0-0.15) is somewhat. smaller, capacity retention, rate capability, and thermal stability at highly oxidized state were significantly improved comparing to the undoped Li[Ni1/3Co1/3Mn1/3]O-2. Fluorine substitution for oxygen made it possible to use the cathode material at 4.6 V cut-off limit. (c) 2005 Elsevier B.V. All rights reserved.