Laser-Induced Regeneration of Spent LiMn₂O₄ Cathode Into High-Performance Ni-Doped LiMn₂O₄ Cathode

The rapid increase in lithium-ion battery (LIB) production, fueled by the rise of electric vehicles, highlights significant challenges in managing end-of-life LIBs, particularly regarding environmental impact and waste management. Traditional recycling methods, such as pyrometallurgical and hydrometallurgical processes, are energy-intensive and consume substantial reagents. In this study, a laser-assisted regeneration method is introduced for LiMn₂O₄ (LMO) cathodes, enabling in situ Ni doping into spent LMO cathodes (r-LMO-Ni) to enhance electrochemical performance. Surface Ni-doping improves interfacial processes and reduces capacity loss at lower temperatures by creating a new interface with a lower charge transfer energy barrier. The r-LMO-Ni cathode surpasses pristine LMO cathodes, achieving a specific capacity of 112.95 mA h g^-1 at 1 C and retaining 95.1% of its capacity after 200 cycles at 0 °C. A techno-economic analysis supports the feasibility of this laser-assisted regeneration approach, offering an innovative pathway for upcycling spent cathodes and developing next-generation Mn-based cathodes.