Solvothermal method for making lithium iron phosphate

A solvothermal method for making lithium iron phosphate, comprising:

• providing a precursor solution for synthesizing lithium iron phosphate, wherein the precursor solution comprises a solvent mixture comprising an organic solvent and water;
• solvothermal reacting the precursor solution to obtain a first suspension liquid;
• filtering the first suspension liquid to obtain a wet lithium iron phosphate material and a filtrate, wherein the filtrate comprises the organic solvent, the water, and a byproduct of the solvothermal reacting;
• flash evaporating the filtrate to respectively obtain the water and a second suspension liquid, wherein the second suspension liquid comprises the organic solvent and the byproduct suspended in the organic solvent;
• separating the byproduct from the organic solvent of the second suspension liquid;
• mixing the water obtained from flash evaporating the filtrate and a part of the organic solvent obtained from separating the byproduct from the organic solvent of the second suspension liquid to obtain a first washing liquid, and countercurrent washing the wet lithium iron phosphate material by using the first washing liquid to obtain a purified wet lithium iron phosphate material and a second washing liquid;
• and
• drying the purified wet lithium iron phosphate material to obtain the lithium iron phosphate.