Comparative experiment on layered Li（Ni1/3Co1/3Mn1/3）O2 as the alternative material for LiCoO2

This work was financially supported by the National Natural Science Foundation of China （No.50472093）.

Comparative experiment on layered Li(Ni1/3Co1/3Mn1/3)O2 as the alternative material for LiCoO2

The characteristics and electrochemical properties of the layered Li(Ni1/3Co1/3Mn1/3)O2 have been investigated by using the X-ray diffraction (XRD), scanning electron microscopy (SEM), and cyclic voltammograms (CV). The Li(Ni1/3Co1/3Mn1/3)O2 powders were synthesized by coprecipitation method. The as-synthesized Li(Ni1/3Co1/3Mn1/3)O2 has well-shaped crystals with a uniform particle size distribution at ～500 nm. A reversible discharge capacity of 165 mAh/g at a current of 40 mA/g between 2.7-4.35 V, with stable cycling performance has been obtained. Moreover, the discharge capacity rises up to 190 mAh/g, when the cutoff voltage increases to 4.6 V. The excellent cycling performance at a higher cutoff operating voltage (up to 4.8 V) could be attributed to the well-retention of the microstructure of synthesized Li(Ni1/3Co1/3Mn1/3)O2 powders. Comparatively, LiCoO2 suffered structure degradation at a higher cutoff voltage. However, the high rate properties of LJ(Ni1/3Co1/3Mn1/3)O2 is not as good as LiCoO2, so its electrical conductivity must be improved.