Multi-strategy synergistic Li-rich layered oxides with fluorine-doping and surface coating of oxygen vacancy bearing CeO2 to achieve excellent cycling stability

Li-rich layered oxides (LLOs) have attracted extensive attentions because of their high reversible capacity and operating voltages for advanced lithium-ion batteries. However, the practical applications of LLOs are restricted by the rapid decay of capacity and voltage. Herein, multi-strategy synergistic Li1.2Mn0.54Ni0.13Co0.13O2 cathode materials with flourine-doping and surface coating of oxygen vacancy bearing CeO2 are prepared through a processing involving co-precipitation and subsequent calcination. The obtained cathode materials exhibit micron-sized olive-shaped particles that are comprised by nanoscale primary particles. Electrochemical testing results indicate that the multi-strategy synergistic LLO exhibits discharge specific capacities of 287.4 mAh g(-1) at 0.2 C and 211.3 mAh g(-1) at 2 C. Compared to the pristine LLO without modifications, high capacity retentions of 76.3% after 500 cycles at 2 C, and 79.1% after 600 cycles at 5 C have been observed for the modified LLO, which are almost 2.0 and 2.5 times that of the pristine LLO. Besides, a voltage drop of 0.511 V after 500 cycles at 2 C, and a voltage drop of 0.514 V after 600 cycles at 5 C are also observed, indicating inhibited voltage attenuation. This work demonstrates that multi-strategy synergy by flourine-doping and surface coating of oxygen vacancy bearing CeO2 can effectively enhance the cycling stability and restrain voltage attenuation of LLO cathode materials.

Automated summary

Multi-strategy synergistic Li1.2Mn0.54Ni0.13Co0.13O2 cathode materials with flourine-doping and surface coating of oxygen vacancy bearing CeO2 have been successfully prepared. The modified cathode materials exhibit improved cycling stability and restrained voltage attenuation compared to pristine LLO. This work demonstrates the effectiveness of multi-strategy synergy for enhancing the electrochemical performance of Li-rich layered oxides.