Three-dimensional Li1.2Ni0.2Mn0.6O2 cathode materials synthesized by a novel hydrothermal method for lithium-ion batteries

摘要

Three-dimensional (3D) hierarchical Li-rich Li1.2Ni0.2Mn0.6O2 microspheres are directly prepared by a novel hydrothermal method without calcination. The preparation procedure involves a co-precipitation process for precursor microspheres and subsequent hydrothermal reaction with different concentration of lithium source at 220 degrees C. The prepared layered materials are composed of stacked nanorods with the length of 100-200 nm. When used as cathode material of lithium-ion battery, the material synthesized by appropriate concentration of lithium source exhibits remarkable electrochemical performances with an initial discharge specific capacity of 269 mA h g(-1) and a first Coulombic efficiency of 82.8% at 0.1 C. Meanwhile, a high reversible specific capacity of 121.3 mA h g(-1) can be achieved after 100 cycles at 5 C, revealing the good rate capability. These results demonstrate that the direct hydrothermal method without calcination is an effective and energy-saving approach to synthesize 3D Li-rich cathode materials for lithium-ion batteries. (C) 2018 Elsevier B.V. All rights reserved.