It is challenging to balance the cyclability and rate capability of single crystal nickel-rich cathode mate-rials (Ni ＞ 0.8).Multicomponent oxides by spray pyrolysis shows potential as highly-reactive precursors to synthesize single crystal nickel-rich cathode at lower temperature,yet Ni2+ will severely inhibit par-ticle growth when Ni content exceeds 0.9.Herein,lithium nitrate (LiNO3) with low melting point and strong oxidation is introduced as collaborate lithium salts for fabrication of well-dispersed submicron and micron single crystal LiNi0.9Co0.055Mn0.045O2 (NCM90) cathode without extra unit operation.By changing amount of LiNO3,particle size regulation is realized and cation disorder can be diminished.The as-prepared material with optimal content of 4 wt％ LiNO3 (NCM90-4LN) displays the most appropri-ate particle size (1 μm) with approximately stoichiometric structure,and presents better kinetics char-acterization of lithium-ion diffusion (15％ higher than NCM90) and good electrochemical performance with specific discharge capacity of 220.6 and 173.8 mAh g-1 at 0.1C and 10C at room temperature,respectively.This work broadens the conventional research methodology of size regulation for single crystal Ni-rich cathode materials and is indispensable for the development of designing principal of nickel-rich cathode materials for lithium-ion batteries.