Niu, Jiahui, et al. Process Safety and Environmental Protection 190 (2024): 77-84.
Lithium-ion batteries (LIBs) are critical energy storage devices experiencing rapid growth, which has led to increasing metal waste from spent LIBs. A major challenge in recycling these batteries lies in separating cathode materials from aluminum (Al) foil due to the strong adhesive properties of polyvinylidene fluoride (PVDF). To address this, a novel low-melting mixture solvent (LoMMS) based on a choline chloride-xylitol system was developed, offering advantages such as low toxicity, cost-effectiveness, and environmental sustainability.
Preparation Procedure:
A choline chloride-xylitol solvent mixture was prepared at a 2:1 mass ratio. The components were weighed accurately to prepare a 70% solution and placed in a 50 mL beaker. The mixture was heated and magnetically stirred at 80 °C for 15 minutes until a uniform, transparent liquid formed. Upon completion, the mixture was allowed to cool to room temperature, resulting in the choline chloride-xylitol LoMMS system.
The method for separating cathode materials from Al foil in discarded LIBs, specifically lithium cobalt oxide (LCO), using this LoMMS system is illustrated in the accompanying figure. Optimal separation conditions were achieved with a 2:1 molar ratio of choline chloride to xylitol.