Preparation method for and use of high-performance lithium iron phosphate

Disclosed are a preparation method for and use of high-performance lithium iron phosphate. The method comprises the following steps: dispersing a lithium salt into a solvent A, and adding an organic acid to adjust the pH to obtain a mixed solution; dispersing porous iron phosphate into a solvent B, and adding an organic carbon source to obtain a mixed slurry A; adding the mixed slurry A into the mixed solution; grinding the obtained slurry; adding a dispersing agent into the grinding material for stirring and dispersing to obtain a mixed slurry B; placing the mixed slurry B under the pressure of 100-1000 Pa for aging and drying; and sintering the obtained dry material in an inert atmosphere to obtain lithium iron phosphate. According to the present invention, the lithium salt and the organic carbon source are stably embedded into the porous iron phosphate structure, so that the reaction is more effective and complete, the generation of impurity phases in the finished product is reduced, and the prepared product has a more uniform and rounded particle morphology, more excellent electrochemical performance, and long cycle performance.