Exposing Microstructure Evolution Of Ni-Rich Ni-Co-Al Hydroxide Precursor

Preparing excellent hydroxide precursor is a significant step in the synthesis of high-energy-density Ni-Rich cathode materials. Efforts to address their limited cycle life have focused on the structure of the precursor. Herein, we showed a systematic survey to reveal the structural evolution of Ni-Rich Ni-Co-Al hydroxide precursor under different synthesis conditions. Under a certain pH, the higher the ammonia concentration is, the larger the primary particle size gradually becomes. Simultaneously, at the low pH (pH = 11.2), Ni-Rich Ni-Co-Al hydroxide precursor is consisted of four phases: Ni(OH)(2), AlO(OH), Al (OH)(3) and Al-2(SO4)(3) with the space group P-3 m1, Cmcm, P21/n and R-3, respectively. At the harsh pH (pH = 11.8), the precursor is consisted of two phases: Ni(OH)(2), and Al(OH)(3) with the space group P3 m1 and P21/n, respectively. This study provided a significant guidance for the design of the precursor with special structure. (C) 2020 Elsevier Ltd. All rights reserved.