This review article discusses the recycling of spent lithium-ion batteries (LIBs) for a sustainable future, focusing on recent advancements in recycling technologies. LIBs are widely used in electronic devices and electric vehicles, and their recycling is crucial for recovering valuable metals like cobalt and lithium, as well as mitigating environmental pollution. Various recycling methods, including direct recycling, pyrometallurgy, hydrometallurgy, bio-hydrometallurgy, and electrometallurgy, are used to resynthesize LIBs. Each method has its own benefits and drawbacks, and this review critically evaluates recent advances in these technologies, including the development of recycling processes, identification of products obtained from recycling, and the effects of recycling methods on environmental burdens. Insights into chemical reactions, thermodynamics, kinetics, and the influence of operating parameters of each recycling technology are provided. The sustainability of recycling technologies, such as life cycle assessment and life cycle cost analysis, is critically evaluated. The review also presents existing challenges and future prospects for further development of sustainable, highly efficient, and environmentally benign recycling of spent LIBs to contribute to the circular economy. Direct recycling is one of the most promising methods for converting spent LIBs into resources. It involves discharging and dismantling spent LIBs, recovery of electrolytes, separation of electrode materials or metal foils, and regeneration of electrode materials. The regeneration of cathode materials involves relithiation of degraded cathodes using solid medium or aqueous solution with a short annealing step with excess Li2CO3. The main regeneration methods applied to cathode materials include solid-state reactions, hydrothermal treatment, coprecipitation, the sol-gel method, and carbon-thermal reduction. The regeneration of anode materials involves removing impurities and restoring the graphite crystal lattice through high temperature processes. The regeneration of anode materials can be achieved through thermal treatment and functionalization, which includes modification and composition changes to enhance electrochemical performance. Pyrometallurgy is another widely used method for recycling spent LIBs, involving high-temperature processes to recover valuable metals. The chemical transformations during pyrometallurgical processes include carbothermic reduction, thermite reduction, additive-assisted transformation, and regeneration of cathodes. The regeneration of cathode materials aims to extract Co and Li from spent LIBs and regenerate high value-added products. The regeneration of anodes involves the recycling of graphite anodes, which are used as reductants to facilitate the recycling of cathodes. The regeneration of anodes can be achieved through high temperature processes, which include the dissociation, decomposition, and separation of impurities and subsequent graphitization of spent graphite. The regeneration of binders, separators, and electrolytes involves the transformation of these components for potential recycling and upgrading. The thermal degradation of PVDF produces F-containing gases, which can be mitigated through thermal defluorination techniques. The thermal decomposition of PTFE produces fluorocarThis review article discusses the recycling of spent lithium-ion batteries (LIBs) for a sustainable future, focusing on recent advancements in recycling technologies. LIBs are widely used in electronic devices and electric vehicles, and their recycling is crucial for recovering valuable metals like cobalt and lithium, as well as mitigating environmental pollution. Various recycling methods, including direct recycling, pyrometallurgy, hydrometallurgy, bio-hydrometallurgy, and electrometallurgy, are used to resynthesize LIBs. Each method has its own benefits and drawbacks, and this review critically evaluates recent advances in these technologies, including the development of recycling processes, identification of products obtained from recycling, and the effects of recycling methods on environmental burdens. Insights into chemical reactions, thermodynamics, kinetics, and the influence of operating parameters of each recycling technology are provided. The sustainability of recycling technologies, such as life cycle assessment and life cycle cost analysis, is critically evaluated. The review also presents existing challenges and future prospects for further development of sustainable, highly efficient, and environmentally benign recycling of spent LIBs to contribute to the circular economy. Direct recycling is one of the most promising methods for converting spent LIBs into resources. It involves discharging and dismantling spent LIBs, recovery of electrolytes, separation of electrode materials or metal foils, and regeneration of electrode materials. The regeneration of cathode materials involves relithiation of degraded cathodes using solid medium or aqueous solution with a short annealing step with excess Li2CO3. The main regeneration methods applied to cathode materials include solid-state reactions, hydrothermal treatment, coprecipitation, the sol-gel method, and carbon-thermal reduction. The regeneration of anode materials involves removing impurities and restoring the graphite crystal lattice through high temperature processes. The regeneration of anode materials can be achieved through thermal treatment and functionalization, which includes modification and composition changes to enhance electrochemical performance. Pyrometallurgy is another widely used method for recycling spent LIBs, involving high-temperature processes to recover valuable metals. The chemical transformations during pyrometallurgical processes include carbothermic reduction, thermite reduction, additive-assisted transformation, and regeneration of cathodes. The regeneration of cathode materials aims to extract Co and Li from spent LIBs and regenerate high value-added products. The regeneration of anodes involves the recycling of graphite anodes, which are used as reductants to facilitate the recycling of cathodes. The regeneration of anodes can be achieved through high temperature processes, which include the dissociation, decomposition, and separation of impurities and subsequent graphitization of spent graphite. The regeneration of binders, separators, and electrolytes involves the transformation of these components for potential recycling and upgrading. The thermal degradation of PVDF produces F-containing gases, which can be mitigated through thermal defluorination techniques. The thermal decomposition of PTFE produces fluorocar