The invention relates to a rare-earth
doping modified
lithium ion battery ternary positive
electrode material and a preparation method of the rare-earth
doping modified
lithium ion battery ternary positive
electrode material. The chemical general formula of the material is as follows: LiNiaCo<1-a-b>MnbRxO2 / M, wherein a is more than 0 and less than 1, b is more than 0 and less than 1, (1-a-b) is more than 0 and less than 1, x is more than 0.005 and less than 0.1, R is one or more of rare-earth
lanthanum,
cerium,
praseodymium and
samarium, and M is a composite cladding layer of
oxide of aluminum,
titanium or
magnesium and carbon. The soluble
metal nickel salt,
cobalt salt,
manganese salt and rare-earth compound are mixed to prepare a mixed
salt solution, the mixed
salt solution is reacted with a mixed alkaline solution prepared by mixing NaOH and
ammonium hydroxide, after the reaction solution is filtered, washed and dried, the obtained product is uniformly mixed with
lithium salt
powder to be ball milled, then the mixture is calcined at the high temperature and coated with the composite cladding layer of the aluminum,
titanium or
magnesium oxide and carbon, and finally the calcined mixture is calcined at a constant temperature to obtain the rare-earth
doping modified
lithium ion battery ternary positive
electrode material. After doping the
rare earth, the
metal oxide and carbon composite cladding layer, which are cheap and easy to obtain, are adopted, so that the
cycling performance and the rate performance can be improved, and the charging-discharging efficiency of the material also can be improved.