Sustainable approach for reclamation of graphite from spent lithium-ion batteries

Abstract A scalable and facile regeneration route is utilized to recover the graphite from a spent lithium-ion battery (LIB). Eco-friendly organic acid is employed as a leaching-curing reagent for the present work. All the unwanted content of elements e.g. Ni, Co, Li, Cu and Al has been completely terminated from the graphite after the purification step without any additional calcination process. The optical, structural and electrochemical properties of as-reclaimed graphite have been studied by several analytical methods. Regenerated graphite is restored to its layered crystal structure along with expansion in the interlayer distance, and the same is confirmed from scanning electron microscopy and X-ray diffraction analysis respectively. Notably, high purity graphite is achieved and tested in its electrochemical storage property in supercapacitor (SC) applications. As an outcome, recreated graphite exhibits a maximum areal capacitance of 285 mF cm⁻² at 5 mV s⁻¹. The fabricated symmetric SC demonstrates the superior energy storage performance in terms of durability and higher capacitance (131 mF cm⁻²) with better capacity retention over several cycles. It is worth mentioning that this curing process is a facile route, consumes lower energy and eco-friendly methodology and thereby may have futuristic extent for the bench scale reclamation of graphite from spent LIBs.