Using analytical transmission electron microscopy (TEM) techniques real a zigzag layer on surface of the cycled particles of LiNi1/3Co1/3Mn1/3O2 cathode after 300 discharge/charge cycles. The Ni, Mn content in the zigzag layer of the cycled particle has decreased rapidly from interior to edge of the ziszag layer of the cycled particles. The structure of LiNi1/3Co1/3Mn1/3O2 oxide was gradually destructed front hexagonal cell with P3(1) 12 at interior region to fcc lattice of alpha-NaFeO2 at edge of the zigzag layer of the cycled particles. These experimental data provide the compositional and structural origins of the capacity decrease in the Li-ion battery. (C) 2008 Published by Elsevier B.V.