Insight into the evolution of precursor and electrochemical performance of Ni-rich cathode modulated by ammonia during hydroxide precipitation

Ni-rich cathode material LiNi0.6Co0.2Mn0.2O2 with the advantage of relative high capacity, low cost and high safety has been realized mass industrial production. To maximize the electrochemical performance of LiNi0.6Co0.2Mn0.2O2, it is highly necessary to gain insight into the inherent laws of precipitation process and precisely control the characterization of secondary and primary particle of precursor. Herein, the evolution of structure, morphology, D50, tap density, {010} facts for Ni0.6Co0.2Mn0.2(OH)2 precursor and the electrochemical performance of corresponding cathode modulated by ammonia during hydroxide precipitation are investigated. The particle size, D50, tap density and morphology are charged with the increase of reaction time under different of ammonia concentration. When the feeding time is larger than 32 h, the steady state of the continuous precipitation is reached. The higher amount of ammonia leads to the formation of precursor crystal with higher percentage of (001) plane and cathode with better electrochemical performance. The understanding of the evolution of precursor and electrochemical performance of Ni-rich cathode modulated by ammonia during hydroxide precipitation would provide new a guiding significance for the controllable preparation of other lithium transition metal oxide materials. •Evolution of precursor is modulated by ammonia during hydroxide precipitation.•Steady state of precipitation is reached when feeding time is larger than 32 h.•Higher amount of ammonia enhances the percentage of area for (001) plane.