Lithium-manganese-rich material, preparation method for same, and applications thereof

A Lithium-Manganese-rich material comprising a substrate and a coating layer coated on a surface of the substrate;

• the substrate comprises a substance represented by a chemical formula Li1.2+x[(MnaCobNicM1−a−b−c)1−dM′d]0.8−xO2, the coating layer comprises a substance represented by a chemical formula Nau[Liv(MnaCobNicM1−a−b−c)γM′1−v−γ]O2, wherein 0≤x≤0.3, 0.5≤a≤1, 0≤b≤0.5, 0≤c≤0.5, 0≤d≤0.1, 0.4≤u<5/6, 0.167 ≤v0.5, 0.5≤γ≤1, M and M′ are respectively and independently at least one element selected from the group consisting of Al, B, Ba, Ce, Cr, Cu, Fe, K, La, Mg, Mo, Na, Nb, Os, Pr, Re, Ru, Sc, Sr, Sm, Ta, Ti, V, W, Y, Yb, Zn and Zr;
• the value of a in the substrate equals the value of a in the coating layer;
• the value of b in the substrate equals the value of b in the coating layer;
• and the value of c in the substrate equals the value of c in the coating layer;
• and
• the coating layer in the Lithium-Manganese-rich material has a thickness of 10-100 nm.