Direct regeneration of spent LiFePO 4 cathode materials: challenges, strategies, modifications, and economic benefits

Abstract The exponential surge in global demand for clean energy has significantly propelled the extensive deployment of lithium‐ion batteries (LIBs), which serve as pivotal energy storage components. As the initial generation of commercial LIBs progressively reaches their end‐of‐life stage, the recycling of spent lithium iron phosphate batteries (SLFPs) and the associated resource regeneration and utilization have emerged as critical concerns within the industry. This review compiles and evaluates the most recent advancements in the direct regeneration of SLFPs cathode materials. A comprehensive analysis is conducted to elucidate the fundamental causes of material degradation and the attendant technical challenges. Additionally, an in‐depth summary of the prevalent direct regeneration methodologies employed in recent years is presented, encompassing the solid‐phase sintering technique, hydrothermal process, molten salt method, and electrochemical approach. Furthermore, the investigation delves into the underlying mechanisms by which surface modification techniques and ion‐doping strategies influence the performance characteristics of regenerated materials. From an economic perspective, a comparative assessment of the costs and revenues associated with various regeneration technologies is performed. Conclusively, in light of the existing limitations in current research, prospective directions are proposed, including the establishment of a comprehensive recycling and utilization framework, the facilitation of industrial implementation, and the refinement of characterization techniques for spent batteries.