Sustainable recycling technologies for lithium-ion battery cathode materials: Recent progress

With the widespread deployment and extensive utilization of lithium-ion batteries (LIBs) across various sectors, battery recycling has emerged as a critical concern for sustainable development. As the most valuable and resource-intensive component of LIBs, cathode materials play a central role in enabling resource conservation, reducing the ecological footprint and reinforcing environmental protection. This review summarizes recent advances in recycling technologies for LIB cathode materials, with particular emphasis on green and sustainable process design. Optimization strategies for conventional hydrometallurgical and pyrometallurgical routes are first discussed, highlighting efforts to lower energy consumption, chemical usage, and environmental emissions. Emerging direct regeneration and closed-loop recycling approaches are then reviewed, demonstrating their potential to preserve crystal structures, improve material reuse efficiency, and reduce overall processing intensity. Through comparative analysis, key challenges such as high energy demand, complex processing steps, and performance variability of recycled products are identified. Finally, future research directions are outlined, focusing on environmentally benign recycling chemistries, process integration, life-cycle-oriented evaluation, and high-value utilization of recycled cathode materials. These insights aim to guide the development of greener and more sustainable battery recycling technologies. • SLIBs exhibit remarkable value-added potential in the circular economy. • The recovery efficiencies of hydrometallurgy, pyrometallurgy, and direct regeneration are systematically compared. • Green reagents and closed-loop systems contribute to the sustainable development in cathode material recovery.