The invention discloses a
lithium-rich
manganese-based positive
electrode material and a preparation method, and relates to the technical field of
lithium ion battery positive
electrode materials, and the preparation method comprises the following steps: jointly dropwise adding a
lithium acetate
aqueous solution and a
transition metal salt
aqueous solution into a
citric acid aqueous solution, maintaining the
reaction temperature, and continuously stirring to form gel; and carrying out secondary
calcination on the gel to obtain a lithium-rich
manganese-based positive
electrode material precursor, carrying out
high shear stress and heat treatment
combined treatment on the lithium-rich
manganese-based positive
electrode material precursor, washing, and
drying to finally obtain the lithium-rich manganese-based positive
electrode material. The lithium-rich manganese-based positive
electrode material is prepared by adopting a
sol-
gel method, a two-step
calcination method and a
high shear stress and heat treatment combined mode,
lattice oxygen can be stabilized by introducing
oxygen vacancies, and the
cycling stability is improved; by introducing the lithium vacancy, the migration energy of lithium ions can be reduced, the migration of the lithium ions is accelerated, and the rate capability is improved; the generation of the disordered layer hinders the contact between the
electrolyte and the internal material, the reaction between the material and the
electrolyte is reduced, the stress caused by lattice
distortion is relieved by the internal local disorder, and the stability of the material is enhanced. The lithium-rich manganese-based positive electrode material prepared by the invention is applied to a
lithium ion battery and shows excellent electrochemical performance, and the preparation method hardly generates waste liquid and shows the characteristic of environmental friendliness.