The article provides a comprehensive review of recent advancements in the recycling of spent lithium-ion batteries (LIBs) to address environmental and sustainability challenges. LIBs, widely used in electronic devices and electric vehicles (EVs), require efficient recycling methods to recover valuable metals like cobalt and lithium and mitigate environmental pollution. The review covers various recycling techniques, including direct recycling, pyrometallurgy, hydrometallurgy, biohydrometallurgy, and electrometallurgy, highlighting their benefits and drawbacks. It discusses the chemical reactions, thermodynamics, kinetics, and operating parameters of each method, as well as their sustainability through life cycle assessment and techno-economic analysis. The review also addresses existing challenges and future prospects, emphasizing the need for sustainable, highly efficient, and environmentally friendly recycling technologies to support a circular economy. The authors, experts in environmental science and engineering, provide insights into the latest research trends and propose directions for further development in LIB recycling.The article provides a comprehensive review of recent advancements in the recycling of spent lithium-ion batteries (LIBs) to address environmental and sustainability challenges. LIBs, widely used in electronic devices and electric vehicles (EVs), require efficient recycling methods to recover valuable metals like cobalt and lithium and mitigate environmental pollution. The review covers various recycling techniques, including direct recycling, pyrometallurgy, hydrometallurgy, biohydrometallurgy, and electrometallurgy, highlighting their benefits and drawbacks. It discusses the chemical reactions, thermodynamics, kinetics, and operating parameters of each method, as well as their sustainability through life cycle assessment and techno-economic analysis. The review also addresses existing challenges and future prospects, emphasizing the need for sustainable, highly efficient, and environmentally friendly recycling technologies to support a circular economy. The authors, experts in environmental science and engineering, provide insights into the latest research trends and propose directions for further development in LIB recycling.