High-capacity high-pressure-density lithium battery positive electrode material and preparation method thereof

The invention discloses a high-capacity high-pressure-density lithium battery positive electrode material and a preparation method thereof. The method comprises the following steps: 1) adding a part of lithium salt into a solvent, and grinding or crushing to a certain particle size; 2) mixing the other part of lithium salt, a phosphorus source, an iron source and a conductive agent with the lithium salt in the step 1), supplementing a certain amount of solvent for grinding, and then drying to obtain a precursor; and 3) sintering the precursor obtained in the step 2) under the protection of an inert atmosphere to obtain the lithium battery positive electrode material. According to the method, a part of lithium salt is ground to a certain particle size, under the high-temperature sintering condition, the small-particle lithium salt is high in reaction activity, a carbothermal reduction reaction can be preferentially generated, meanwhile, a fast ion conductor compound can be generated, the electronic conductivit