Recent developments and the future of the recycling of spent graphite for energy storage applications

This review provides an extensive analysis of the recycling and regeneration of battery-grade graphite obtained from used lithium-ion batteries. The main objectives are to address supply-demand challenges and minimize environmental pollution. The study focuses on the methods involved in obtaining, separating, purifying, and regenerating spent graphite to ensure its suitability for high-quality energy storage. To improve the graphite recovery efficiency and solve the problem of residual contaminants, techniques like heat treatment, solvent dissolution, and ultrasound treatment are explored. Wet and pyrometallurgical purification and regeneration methods are evaluated, considering their environmental impact and energy consumption. Sustainable and cost-effective approaches, including acid-free purification and low-temperature graphitization, are highlighted. Specific requirements for regenerated graphite in lithium-ion batteries and supercapacitors are discussed, emphasizing customized recycling processes involving acid leaching, high-temperature treatment, and surface coating. Valuable information for the development of efficient and sustainable energy storage systems is provided, addressing environmental issues, and how to meet the increasing demand for graphite anodes.