The invention relates to the technical field of
lithium ion batteries, and particularly discloses a high-
voltage composite positive
electrode material as well as a preparation method and application thereof. A preparation method of the high-
voltage composite positive
electrode material disclosed by the invention comprises the following steps: co-precipitating a
nickel source, a
cobalt source, a
manganese source and a
mixed solution containing a first
doping element, a second
doping element and a third
doping element to obtain a precursor; and S2, mixing the precursor with a
lithium source, and
sintering to obtain the high-
voltage positive
electrode material, and S3, crushing the high-voltage positive
electrode material, repairing the crushed high-voltage positive
electrode material through mixed repairing gas, and cooling and sieving the crushed high-voltage positive
electrode material to obtain the high-voltage composite positive electrode material. According to the invention, a high-entropy stable bulk phase is constructed through multi-element co-doping, and a surface interface is optimized in combination with a unique
gas phase repair technology, so that the problem that the
cycling stability and rate capability of the positive electrode material are sharply deteriorated under
high voltage is synergistically solved, and the prepared positive electrode material has
high voltage, high capacity and long cycle life.