Ternary precursor and preparation method therefor, ternary positive electrode material, and electric apparatus

A preparation method of ternary precursor, comprising:

• providing a first mixed nickel-cobalt-manganese metal salt solution and a second mixed nickel-cobalt-manganese metal salt solution;
• adding a first base solution having a first pH value and a first ammonia concentration to a first reactor, and adding the first mixed nickel-cobalt-manganese metal salt solution, an alkali solution, and ammonia to the first reactor to maintain the pH value and the ammonia concentration unchanged, so as to form a seed crystal slurry of ternary precursor;
• and
• adding water as a base solution to a second reactor, adding the seed crystal slurry of ternary precursor to adjust the base solution to a second pH value and a second ammonia concentration, and adding the second mixed nickel-cobalt-manganese metal salt solution, an alkali solution, ammonia, and the seed crystal slurry of ternary precursor to the second reactor to maintain the pH value and the ammonia concentration unchanged, so as to form a ternary precursor;
• wherein primary particles or whiskers of the ternary precursor are distributed in a radial direction;
• and a deformation stacking fault probability fD of the ternary precursor is ≤2.5%, and the deformation stacking fault probability fD is calculated as follows:
• fD=0.1552×B (101)−0.03233×B (102)−0.4399/D (001),
• where B (101) is a full width at half maximum in an X-ray diffraction pattern of a (101) crystal plane of the ternary precursor, B (102) is a full width at half maximum in an X-ray diffraction pattern of a (102) crystal plane of the ternary precursor, and D (001) is a full width at half maximum in an X-ray diffraction pattern of a (001) crystal plane of the ternary precursor, where the full widths at half maximum are measured in degrees;
• wherein the ternary precursor comprises an inner core and a shell enclosing the inner core, a radius R of the inner core is 0.1-6.0 μm, and a thickness h of the shell is 2-10 μm;
• wherein a molar ratio of nickel, cobalt, and manganese in the first mixed nickel-cobalt-manganese metal salt solution is x:
• y:
• (1-x-y), wherein 0.8≤x<1.0, 0<y<0.2, and x+y<1;
• and a molar ratio of nickel, cobalt, and manganese in the second mixed nickel-cobalt-manganese metal salt solution is a:
• b:
• (1-a-b), wherein 0.8≤a<1.0, 0<b<0.2, a+b<1, and a≤x.