Nickel-Rich Layered Microspheres Cathodes: Lithium/Nickel Disordering and Electrochemical Performance

Nickel-rich layered metal oxide materials are prospective cathode materials for lithium ion batteries due to the relatively higher capacity and lower cost than LiCoO2. Nevertheless, the disordered arrangement of Li+/Ni2+ in local regions of these materials and its impact on electrochemistry performance are not well understood, especially for LiNi1–x–yCoxMnyO2 (1–x–y > 0.5) cathodes, which challenge one’s ability in finding more superior cathode materials for advanced lithium-ion batteries. In this work, Ni–Co–Mn-based spherical precursors were first obtained by a solvothermal method through handily utilizing the redox reaction of nitrate and ethanol. Subsequent sintering of the precursors with given amount of lithium source (Li-excess of 5, 10, and 15 mol %) yields LiNi0.7Co0.15Mn0.15O2 microspheres with different extents of Li+/Ni2+ disordering. With the determination of the amounts of Li+ ions in transition metal layer and Ni2+ ions in Li layer using structural refinement, the impact of Li+/Ni2+ ions di...