O3/P2 double-phase composite sodium ion positive electrode material as well as preparation method and application thereof

The invention provides an O3/P2 dual-phase composite sodium ion positive electrode material and a preparation method and application thereof, the O3/P2 dual-phase composite sodium ion positive electrode material comprises: an O3-phase sodium ion positive electrode material having a chemical formula of NaXNiaFebMncZn (0.333-a) O2, in which X is greater than or equal to 0.9 and less than or equal to 1.1, a is greater than or equal to 0 and less than or equal to 0.333, b is greater than or equal to 0.1 and less than or equal to 0.5, and c is greater than or equal to 0.2 and less than or equal to 0.8; the chemical formula of the P2-phase sodium ion positive electrode material is NaxNiaMn1-aFbO2-b/2, X is more than or equal to 0.5 and less than or equal to 0.88, a is more than or equal to 0 and less than or equal to 0.4, and b is more than or equal to 0 and less than or equal to 0.05; the oxides and/or hydroxides coat the surfaces of the O3-phase sodium ion positive electrode material and the P2-phase sodium ion p