Spray drying–assisted recycling of spent LiFePO4 for synthesizing hollow spherical LiFePO4/C

With the booming of new energy storage and power battery industries, sustainable recycling of retired lithium batteries has become an urgent issue in today’s society. This work develops a spray drying–assisted method for recovering used LiFePO4 to high-performance hollow spherical LiFePO4/C composites effectively. The typical technology consists of separation, purification, leaching, spray drying, and a commonly used sintering process. Structural and morphological characterization results show that the particle uniformly distributed regenerated hollow spherical powders with high crystallization and tightly coated nano-conductive carbon films. As a result of the experiment, the recovered LiFePO4/C materials possess prospective Li-ion storage properties with high discharge capacities and outstanding cyclic stability. The LiFePO4/C composite regenerated under an optimized condition shows a high capacity of 141.9 mAh g-1 at 1 C rate and retains a capacity retention of more than 99% after 100 cycles. This work proves that spray drying–assisted method is a promising strategy for recycling spent LiFePO4-based lithium-ion batteries efficiently.