The invention relates to a three-layer core-shell structure positive
electrode material. The three-layer core-shell structure positive
electrode material comprises a three-layer structure, namely, a ternary positive
electrode material inner core, an aluminum
oxide layer and a rapid
ion conductor layer, wherein the aluminum
oxide layer wraps the ternary positive
electrode material inner core, and the rapid
ion conductor layer wraps the aluminum
oxide layer. The invention also comprises a preparation method of the three-layer core-shell structure positive
electrode material. Since the rapid ionconductor wrapping an outer layer of the three-layer core-shell structure positive
electrode material has super strong
ionic conductivity, the integral
ionic conductivity of the Al2O3-coated positiveelectrode material can be improved, the
electric energy loss is reduced, and the cycle property of a battery is improved; moreover, the aluminum oxide layer and the ternary positive electrode materialinner core form a Li-Al-Co-O co-melting body by high-temperature
calcination during the preparation process, the
ionic conductivity of the material can be further improved, and the electrical
conductivity and the
microstructure stability of the
composite material are improved; and by the three-layer core-shell structure, the
corrosion of an
electrolyte to the ternary positive electrode material inner core can be reduced, and the battery safety is improved.