Surface Coating Modification of Lithium-Rich Manganese-Based Oxide as Cathode Material for Lithium-Ion Batteries

Lithium-rich manganese-based oxides (Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 , LMNCO) as cathode materials were prepared by the sol-gel method. Then, LMNCO was coated with γ-basic manganese oxide (γ-MnOOH) to form the composite cathodes. Through the structural characterization and performance test, it is found that the composite cathode with 10% γ-MnOOH coating exhibits the best electrochemical performance. After 50 cycles at 0.1 C (1 C = 200 mA g -1 ), the specific discharge capacity is 264.4 mAh g -1 with capacity retention of 96.1%. Even at a high current density of 1C, its discharge capacity reaches up to 200.5 mAh g -1 after 30 cycles, which suggests that surface coating of γ-MnOOH is an effective strategy for further enhancing the electrochemical performance of LMNCO.