The enhanced high cut-off voltage electrochemical performances of LiNi0.5Co0.2Mn0.3O2 by the CeO2 modification

- The effects of precipitants on CeO2 are investigated in detail.
- The thermal stability of LiNi0.5Co0.2Mn0.3O2 can be enhanced by CeO2.
- Electrochemical performance of LiNi0.5Co0.2Mn0.3O2 is enhanced by CeO2 modification

The CeO2 nano-particles dispersed on the surface of commercial LiNi0.5Co0.2Mn0.3O2, have been prepared by a co-precipitation method, in which ammonium carbonate or ammonium oxalate is served as a precipitant to generate the different precursor of CeO2, respectively. CeO2-modified LiNi0.5Co0.2Mn0.3O2 composites with ammonium oxalate as the precipitant exhibit the best electrochemical properties with a reversible lithium storage capacity of 157.7 mAh g−1 with a retention of 86.36% at 25 °C at the current density 1C after 100 cycles under high cut-off voltage 4.6 V. At higher temperature 55 °C, its discharge capacity changes from 198.2 mAh g−1 to 136.6 mAh g−1 after 100 cycles, with a retention of 68.29%. Besides, it also displays an excellent rate performance with a capacity of 114.0 mAh g−1 at 5C in the 100th cycle. All enhanced performances could be due to the dispersion of CeO2 on the surface of commercial LiNi0.5Co0.2Mn0.3O2 and the synergistic effects between the CeO2 and LiNi0.5Co0.2Mn0.3O2, which leads to the enhanced structural stability and electric conductivity.