Green recovery of solid electrolytes from all-solid-state lithium-ion batteries using low-melting mixture solvents with tunable physical properties

Abstract

All-solid-state lithium-ion batteries (ASSLIBs) are anticipated to be the next generation of high-performance lithium batteries due to their enhanced safety and high energy density. However, the promising widespread application of ASSLIBs will lead to a significant increase in spent batteries, resulting in environmental pollution and resource depletion. Therefore, the development of environmentally friendly recycling methods for ASSLIBs is both urgent and critical. Low-melting mixture solvents (LoMMSs) were proposed by Professor Yu's research group at Tsinghua University in 2023 to facilitate the advancement of green solvents and green chemistry. Here, we utilize LoMMSs to leach metals from solid-state electrolytes (SSEs) of ASSLIBs and apply anti-solvents method to recover metal ions from leachate. Results show that the leaching efficiency of Li is up to 92.5% at a mild temperature of 80 °C within 24 h. The high Li leaching efficiency is ascribed to the coordination interaction. Furthermore, the Li leaching efficiency in large-scale applications shows minimal deviation from the optimal efficiency. This research provides valuable insights into the development of efficient, green, and mild recycling methods for SSEs in ASSLIBs.