The invention discloses a surface-modified high-entropy
lithium-rich
manganese positive
electrode material as well as a preparation method and application thereof, and the surface-modified high-entropy
lithium-rich
manganese positive
electrode material is represented by a general formula Li1 + xNi0. 13Co0. 13Mn0. 54MyNzO2-wAw. The specific preparation method comprises the following steps: respectively weighing a
nickel-
cobalt-
manganese compound, a
lithium salt, an additive I and an additive II, uniformly mixing, carrying out high-temperature
calcination in a
muffle furnace, cooling, crushing, crushing, and screening to obtain the surface-modified high-entropy lithium-rich manganese positive
electrode material. And mixing with an additive III, and carrying out secondary
sintering to prepare the surface high-entropy lithium-rich manganese positive
electrode material. According to the method, different electrostatic fields are generated through co-
doping of a high-d-state orbital element and a low-
electronegativity element, an O2p band is expanded, overlapping between the O2p band and a (TM-O) * band is enhanced, an energy
band gap is reduced, and anion
oxidation reduction reversibility is promoted; by constructing a surface high-entropy change energy band structure, the diversity and
distortion energy of a Mn < 4 + >
local structure are increased, and the formation energy of
oxygen vacancies and the migration energy of
transition metal ions are improved. Through accurate design and controllable preparation of the lithium-rich manganese material and multi-strategy coordinated regulation and control of an energy band structure, the cycle performance and the
voltage attenuation phenomenon of the lithium-rich manganese-based positive
electrode material are improved.