Sustainable Closed-Loop Recycling of Spent Solid Electrolytes and Electrodes in All Solid-State Batteries

Abstract

With rapidly increased lithium ion batteries (LIBs) adoption, the need for sustainable battery recycling is a matter of utmost importance. Spent LIBs contain lithium, cobalt, nickel and other transition metals that are not only economically valuable but are also limited in terms of their geographical availabilities. Conventional recycling technologies, such as pyrometallurgy and hydrometallurgy, tend to be energy intensive, costly, and use toxic chemical processing which can be difficult to handle. Additionally, materials recovery efficiency remains low, due to low recycling rates of other components in the cell such as the liquid electrolyte and lithium salts. This is primarily because today’s LIBs are not designed specifically for recycling ease. While it might be too late for conventional batteries, next generation all solid-state batteries (ASSBs) might instead stand a chance. In this work, we developed a sustainable and practical ASSB recycling model, that involves complete closed-loop recyclability of all components in the cell including the solid electrolyte and electrodes. We demonstrate efficient separation and recovery of the solid electrolyte and spent electrodes from a cycled lithium metal full cell, without using toxic chemicals or energetic processes. These recovered materials are directly regenerated into their original usable formats without any breakdown of their core chemical structure. The fully recycled materials are then used to fabricate new ASSBs, achieving the same performance level as pristine ASSBs. This study provides a promising opportunity for sustainable recovery and recycling of spent ASSBs.