Facile synthesis of lithium-rich layered oxide Li[Li0.2Ni0.2Mn0.6]O2 as cathode of lithium-ion batteries with improved cyclic performance

Abstract

Lithium-rich layered oxide has attracted much attention as a cathode of lithium-ion batteries due to its high specific capacity and relative cheapness. Although much effort has been dedicated to its development, this oxide is not used commercially because of its poor cyclic performance. In this work, we reported a facile synthesis for lithium-rich layered oxide, Li[Li0.2Ni0.2Mn0.6]O2, with improved cyclic performance, in which fast evaporation for precursor formation is introduced. The as-synthesized samples were characterized with X-ray diffraction, Raman spectroscopy and scanning electron microscope, and charge/discharge test. The results indicate that the as-synthesized samples deliver a reversible capacity of ~200 mAh g−1 and remain unchanged after 50 cycles at 0.05 C. The improved cyclic performance can be attributed to the low structural defects in lithium-rich layered oxides, which decrease the oxygen loss and manganese reduction and therefore depress the migration of transition metal ions and phase transformation.