Co-precipitation synthesis of LiNi0.59+xCo0.3-xTi0.1Al0.01O2 (NCTA) as Ni-rich cathode materials and their electrochemical performance

The increasing adoption of electric vehicles (EVs) has driven the demand for efficient, sustainable, and cost-effective cathode materials. Nickel-rich cathode materials (Ni content more than 50%) are highly promising due to their high energy density. However, Ni-rich cathode materials suffer from high capacity fading due to their structural instability and particles microcracking after repeatedly undergo charge/discharge process. Herein, a single-crystal LiNi0.59+xCo0.3-xTi0.1Al0.01O2 (NCTA) was synthesized using a co-precipitation method followed by high annealing temperature with excess lithium. Three synthesis parameters such as washing durations, annealing temperatures and nickel-to-cobalt ratios were optimized and the effects on the structural, morphological, and electrochemical properties also studied systematically. In the first part, co-precipitation synthesis of NCTA_0.59 (LiNi0.59Co0.3Ti0.1Al0.01O2) that annealed at 920 °C was washed with deionized water at different duration. Rietveld refinements revealed that the washed sample exhibited lower cation mixing compared to the unwashed sample showed that the unwashed samples had particle agglomeration and existing of Li residue on the surface of the cathode materials. Interestingly, FESEM revealed that after the washing treatment, the NCTA appeared as single crystals particles with clean, smooth surfaces.