The invention is applicable to the technical field of a
lithium battery and provides a
lithium Ni-Co
aluminate positive
electrode material co-doped with negative ions and positive ions and a preparation method of the positive
electrode material. The method comprises the steps of firstly, pre-
sintering a
lithium Ni-Co
aluminate NCA precursor to form a porous
honeycomb quasi-spherical pre-sintered precursor by employing a pre-
sintering method of spraying a
sodium bicarbonate solution and an F solution; secondly, preparing a solution from a Mg source and Nb source according to a proportion, mixing with the pre-sintered precursor under a water
system, and effectively guiding a Mg and Nb solution into a positive
electrode material substrate through
honeycomb holes; thirdly, spraying an F
ion regulation agent solution during material mixing and lithium supplement by a high mixing
machine so that materials are fully and uniformly mixed; and finally, performing high-temperature
sintering to make a finished product crystallized so as to obtain the lithium Ni-Co
aluminate positive
electrode material co-doped with the negative ions and the positive ions. In the positive
electrode material, positive
ion mixing can be reduced by Nb<4+>, polarization can be reduced by Mg<3+>, the electrochemical performance is improved, no electrochemical reaction of Mg<3+> / Nb<4+> is generated during the charging process, no valence-state change is generated, and an effect of stabilizing a
crystal structure can be achieved; and moreover,
oxygen can be fixed by F negative
ion doping,
oxygen precipitationis reduced, the
material structure is stabilized, and the cycle property is improved.