Enhanced electrochemical performances of layered-spinel heterostructured lithium-rich Li1.2Ni0.13Co0.13Mn0.54O2 cathode materials

Layered Li-rich manganese-based cathode material, Li1.2Ni0.13Co0.13Mn0.54O2, is prepared by a facile solvothermal method, followed by calcination at high temperature. After that, an effective surface modification approach including the pre-coating of dopamine layer and subsequent heating treatment in air is used to synthesize layered-spinel heterostructured Li-rich cathode material. After surface modification, spinel nanoparticles uniformly distribute on the surface of Li-rich cathode material and, as a result, the electrochemical performances of the collected layered-spinel heterostructured cathode material are improved significantly. The produced layered-spinel heterostructured cathode material exhibits a high initial discharge capacity of 276 mA h g(-1) at 0.1 C with an enhanced initial Coulombic efficiency of 87.6%. The reversible capacities are 246 mA h g(-1) after 100 cycles at 0.2 C with a capacity retention of 90.9% and 231 mA h g(-1) after 200 cycles at 1 C with a capacity retention of 95.8%. The reasons for the greatly enhanced electrochemical properties of layered-spinel heterostructured cathode material are discussed in detail.