Regeneration method of lithium iron phosphate in retired lithium battery

The invention relates to the field of lithium battery materials, in particular to a regeneration method of lithium iron phosphate in a retired lithium battery. The method comprises the following steps: pretreating a positive electrode material obtained by decomposing a waste lithium iron phosphate battery to obtain a lithium iron phosphate semi-finished product; mixing the lithium iron phosphate semi-finished product with aluminum powder and carbon fibers, then putting the mixture into a dispersing agent for wet ball milling, pre-drying the obtained mixed slurry to obtain pre-dried powder, andputting the pre-dried powder into an argon atmosphere for purging and drying to obtain dried powder; continuously purging and heating the dried powder in a mixed atmosphere of hydrogen and argon, andkeeping the temperature constant for a period of time to obtain a precursor; continuously carrying out constant-temperature purging on the precursor in a mixed atmosphere of carbon source gas and hydrogen, and then performing