Patent ID: 11916229
Assignee: CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 13:
14. A method for preparing a positive electrode active material, comprising the following steps:
a step of providing an inner core material, wherein: the inner core comprises Li1+xMn1−yAyP1−zRzO4, wherein x is −0.100 to 0.100, y is 0.001 to 0.500, z is 0.001 to 0.100, A is one or more selected from Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb, and Ge;
a coating step, involving: providing an MP2O7 powder and an XPO4 suspension containing a carbon source, adding the inner core material and the MP2O7 powder into the XPO4 suspension containing the carbon source, mixing same, sintering the mixture to obtain an inner core with a first coating layer and a second coating layer, and coating the obtained inner core with the first coating layer and the second coating layer with a polymer by dry coating or wet coating to obtain a positive electrode active material, wherein the polymer comprises one or more selected from a polysiloxane with a linear structure and a polysiloxane with a cyclic structure, and M and X are each independently selected from one or more of Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, and Al, and
the positive electrode active material has a core-shell structure, comprising the inner core and a shell coating the inner core, with the shell comprising the first coating layer coating the inner core, the second coating layer coating the first coating layer, and the third coating layer coating the second coating layer, wherein the first coating layer comprises a pyrophosphate of MP2O7 and a phosphate of XPO4, the second coating layer comprises carbon, the third coating layer comprises the polymer, and the polymer comprises one or more selected from the polysiloxane with a linear structure and the polysiloxane with a cyclic structure.