The invention provides a preparation method of a
single crystal NCM ternary positive
electrode material precursor, which comprises the following steps of S1, adding a Nix: Coy: Mnz
sulfate solution with the total concentration of 1.0-2.2 mol / L, a 4-10 mol / L caustic soda solution and 20%
ammonia water into a reaction unit (10) according to a ratio, and introducing
inert gas to carry out a first-stage reaction under the
reaction conditions that the stirring speed is 800-1100 r / min, the pH is 11.50-13.00, the temperature is 40-60 DEG C, the
inert gas flow is 0.1-2 m<3> / h, x+y+z=1, and 1.0>x> / =0.5, S2, after measuring that the particle D50 is equal to 1.5-1.8 mum, increasing the
ammonia value in the reaction kettle to carry out a second-stage reaction under the
reaction conditions that the stirring speed, the temperature and the
airflow speed are kept unchanged, the
ammonia water concentration is controlled to be 2-7 g / L, the pH is controlled to be 9.00-11.00, concentrating by utilizing a
solid extraction unit (20) to increase the
solid content and adjust the clear speed of a
solid extractor, and finally measuring the particle D50 to be 3.8-4.5 mum and stopping the reaction, and S3, washing,
drying and screening the
slurry to obtain the
single crystal NCM ternary positive
electrode material precursor.