The application provides a composite
manganese-based positive
electrode material, a preparation method thereof and a
lithium ion battery, and the composite
manganese-based positive
electrode material comprises a
manganese-containing positive
electrode material and a
coating layer coated on the surface of the manganese-containing positive
electrode material, and the
coating layer comprises a dioxole-containing
organic matter and a 2-
oxazolidone-containing
organic matter. The manganese-containing positive
electrode material is modified by the dioxole-containing
organic matter and the 2-
oxazolidone-containing organic matter, and the surface of the manganese-containing positive
electrode material is physically formed into a film under the action of physical adsorption, which makes the
ethylene oxide free radicals in the dioxole-containing organic matter and the 2-
oxazolidone in the 2-oxazolidone-containing organic matter rapidly crosslink with each other in the charging and discharging process, so that a uniform, thin and stable CEI film with small polarization degree is formed on the surface of the positive electrode material, the
dissolution of manganese is effectively inhibited, the interface resistance is reduced, and the cycle and rate performance of the positive electrode material are improved.