Composite phosphate positive electrode material and preparation method and application thereof

The invention belongs to the technical field of battery materials, and particularly relates to a composite phosphate positive electrode material and a preparation method and application thereof. Comprising the following steps: performing primary mixing and grinding treatment on raw material components including a phosphorus source, an iron source, a manganese source, a lithium source and a mixed carbon source I and a solvent I to prepare a solid-liquid mixed raw material; carrying out primary grinding treatment on a primary crystallization product, a mixed carbon source II and a solvent II, carrying out primary drying treatment, carrying out primary sintering treatment in an inert atmosphere, carrying out secondary grinding treatment on the primary crystallization product, the mixed carbon source II and the solvent II, carrying out secondary drying treatment, and carrying out secondary sintering treatment in the inert atmosphere to obtain the composite phosphate positive electrode material, the mixed carbon s