Flash recovery of lithium from spent anode graphite by carbothermal shock and water leaching

Abstract

The global boom in electric vehicles has led to an alarming accumulation of lithium-ion battery waste. Battery recycling technologies have primarily focused on cathode metal recovery, while the contaminated anode graphite has been severely neglected. Conventional graphite recovery methods require multiple acid washes or prolonged high-temperature treatment and consume large amounts of energy and chemicals. Here, we develop an ultra-fast carbon thermal shock and water leaching (CTSW) method, which can transiently realize the complete stripping of anode materials, enable 100% recovery of graphite and copper foil, and recover valuable lithium resources. Specifically, carbon thermal shock (CTS) introducing auxiliary media (CaCO₃, Al₂O₃, etc.) promotes lithium aggregation from the interior to the surface of graphite, converts insoluble LiF to Li₂CO₃, achieves deep leaching of >99.5% lithium, and immobilizes the hazardous byproduct, HF, to metal fluoride. Compared to conventional hydrometallurgy, LCA analysis shows that our CTSW method has a significantly lower environmental impact, energy, and cost.