Direct regeneration of spent lithium-ion batteries: Advancing from powder to cell

The rapid advancement of electric vehicles (EVs) has led to a substantial increase in spent lithium-ion batteries (LIBs), necessitating effective recycling pathways to recover the reusable battery components. Traditional recycling methods, such as pyrometallurgy and hydrometallurgy, represent battery-component destructive pathways with high energy consumption and substantial waste emissions, leading to considerable environmental issues. In contrast, direct regeneration technologies preserve the integrity of battery components on certain levels, offering a more sustainable and energy-efficient approach. However, these technologies are hindered by complex pre-treatment procedures, underscoring the need for a simplified route to effectively restore battery performance. This Review categorizes recent advancements in direct regeneration strategies at three levels—powder, electrode, and cell—focusing on their fundamental mechanisms, technological pathways, and socioeconomic sustainability. Among these, cell-level direct regeneration technologies exhibit the highest economic benefits and the lowest waste emissions, positioning them as a promising solution for large-scale battery recovery. By highlighting the potential of cell-level direct regeneration, this review aims to drive further research and development toward scalable and simplified strategies for the efficient reuse of spent LIBs.