Direct recycling of lithium-ion battery materials: separation and regeneration

Abstract

The rapid development of lithium-ion batteries (LIBs) has led to an urgent need for efficient recycling. Among current recycling strategies, direct recycling emerges as a promising alternative to conventional pyrometallurgy and hydrometallurgy, restoring valuable electrode materials while preserving the original crystal structure and minimizing energy consumption.However, direct recycling remains technically immature and faces challenges in practical cost, material purity, scalability, and process integration. This review summarizes recent advances in direct recycling of LIB active materials, following the workflow of disassembly, separation and regeneration, along with material degradation mechanisms. Various thermal, mechanical, and solvent-based separation methods are discussed in terms of their product size, efficiency, material compatibility, and cost. Regeneration methods, including solid-state sintering, solution-based, and molten salt regeneration, are discussed from their relithiation kinetics, processing conditions, upcycling strategies and electrochemical performance of restored materials. Finally, future perspectives are proposed to address current limitations towards scalable and cost-effective direct recycling technologies for sustainable LIB development.