Directional High-Value Regeneration of Lithium, Iron, and Phosphorus from Spent Lithium Iron Phosphate Batteries

Abstract

As lithium-ion batteries (LIBs) are undergoing unprecedented development in electric vehicles (EVs) and renewable grids, recycling spent battery disposal is becoming the dominating issue considering the urgent demand for sustainable resources and eco-friendly development. However, existing recovery methods for spent LIBs still suffer from complex processes and low processing efficiency. Herein, an effective pyroprocessing-based strategy was proposed to recycle spent lithium iron phosphate (LFP) materials, featuring full element regeneration and conversion of high-value products. Specifically, over 99% Li was extracted and converted into high purity lithium carbonate (>99%), while Fe and P were further converted into value-added Fe2P2O7 and Na4P2O7, respectively. Due to the benefits of high efficiency of metal extraction and the reuse of all valuable elements, the pyroprocessing-based strategy potentially generates the profit of 1.44 $ kg–1 of LFP batteries, over three times more than that of the conventional hydrometallurgical process, while the discharges of wastewater and residue are reduced by 66.3 and 93.9%, respectively. This study provides a new pyroprocessing-based approach to the green recovery of all elements of LFP materials in spent LFP batteries.