Recycling graphite (Gr) from spent lithium‐ion batteries (LIBs) presents an attractive means of counteracting the high cost and limited supply of battery‐grade Gr. However, its industrial implementation has yet to be realized, owing to the low economic value and complex separation process. Herein, an existing industrial cathode recycling process is leveraged to recover Gr for secondary use as an LIB anode material. Metallic impurities in the solid residue generated by pyrolysis of spent LIBs are removed by double acid leaching to improve the purity of the recovered Gr. Subsequently, the graphitic matrix is regenerated by heat treatment at a relatively low temperature (1200°C). Nonetheless, the low initial Coulombic efficiency (ICE) of the recovered Gr (62.4%) necessitates incorporation with commercial Gr to enhance anode performance. The resulting composite anode with 20 mass% recovered Gr exhibits an acceptable ICE of 82.0% and enhanced rate and cycling performances. Moreover, it achieves a high energy density of 346.3 Wh kg –1 and retention rate of 79.1% after 500 cycles. This study demonstrates that Gr can be recovered from spent LIBs and reused as an anode material, thereby improving the recovery rate and sustainability of the battery recycling process.
Chng et al. (Thu,) studied this question.