Olivine composite cathode material, preparation method and application thereof, and lithium-ion battery

Abstract

Provided are an olivine composite cathode material, a preparation method, and a lithium-ion battery. The composite cathode material includes a matrix and a composite phase. The matrix has a composition represented by formula I: LiMMnFeM(PO)(RO)Cv, where 0.5≤x<1.3, 0≤y≤0.5, 0<z≤1, 0≤u≤0.01, 0<w≤1, 0<v≤0.05, 0≤≤8, and 0≤b≤1; Mis selected from at least one of Mg, Na, and K; Mis selected from at least one of Ga, Sn, V, Y, Mo, Al, Mg, Ce, Ti, Zr, Nb, Si, W, and In; and R is selected from at least one of Si, Cl, Br, S, Sb, and Sn. The composite phase has a composition represented by formula II: TG, where: 0.1≤m≤5, and 0.1≤n≤5; T is selected from at least one of Ti, Mo, Co, W, Zn, Cu, B, V, Nb, Ta, Pd, Cr, Ag, Al, Mn, Sn, Mg, Sc, Zr, and Hf; and G is selected from N and/or C.