A positive electrode active material, its preparation method and application

Abstract

This application relates to a positive electrode active material, its preparation method, and its application. The positive electrode active material is a layered lithium-rich manganese-based oxide, comprising a dual-alkali metal lithium-rich layered structure and an in-situ generated heteroepitaxial structure. The dual-alkali metal lithium-rich layered structure is a nano-symbiotic structure containing two alkali metal elements, including an R-3m space group structure and a C2 / m space group structure. The heteroepitaxial structure includes one or more non-layered space group structures selected from Fd-3m, Fm-3m, and Pbnm. The solution provided in this application provides a positive electrode active material with good mechanical strength and compressive strength, which can improve the structural stability and material compaction density of the positive electrode sheet. This not only helps the lithium-rich manganese-based positive electrode material to exert its energy density advantage but also improves the thermal stability of the electrode, reduces side reactions, and overall enhances the electrochemical performance and energy density of lithium-ion batteries.

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