Study On Recycling Of Waste Lithium Iron Phosphate Battery

Energy and environmental issues have become increasingly intensified with the development of society.To alleviate the shortage of petroleum energy and environmental pollution,China increases the promotion of electric vehicles to replace the fuel vehicle.But,with the scrapping of electric vehicles,the importance of power battery recycling and disposal is increasing day by day.Lithium iron phosphate batteries which is the largest amount in used has been selected as the recycling research object.This paper proposed a complete recycling process by the study of each step of the processes,and preliminary put forward the operating conditions.The recovery treatment process based on the regeneration technology of positive electrode materials,including dismantling,stripping,regeneration pretreatment,and regeneration.Among them,disassembly is performed manually.In terms of stripping,a cold-shocking method was proposed in this study.The positive electrode was heated in water at 80? for 5 minutes.Then put it in water at 15? mediately.The positive electrode material was separated efficiently and cleanly from the current collector.The separated positive electrode material was treated at a high temperature in an inert atmosphere at 500? for 2 hours,to remove the binder PVDF.Then Li2CO3,FeC2O4·2H2O,and NH4H2PO4 were used as reactants and added to the positive electrode material.The mixture was milled at 500rpm for 2h,and it generated the regenerated precursor.The precursor was heated in an inert atmosphere at 350? for 2h and then at 750? for 8h,and the regenerated cathode material would be prepared.The cold-shocking method in the above flow has a better separation effect than the conventional exfoliation method.The surface of the separated current collector is bright,with no residual cathode material.The peeling process is simple in operation,mild in operating conditions,low in energy consumption.It has good economy,and easily to industrialize.The crystal structure of the regenerated cathode material is regular,and the particle size distribution is uniform,which is between 0.3-0.8?m.The crystal particle has good dispersion,large void ratio and specific surface.The specific charge and discharge capacity of regenerated cathode material is above 130mAh/g at 0.1 C rate.