In Germany, a project led by electrolyte company Elyte Innovations GmbH is pursuing the recovery of the non-metallic components—including lithium salts, solvents and electrolyte additives—from spent lithium-ion batteries. Named SWELL (Stoffliche Wiederverwertung von Elektrolyt-Leitsalzen und-Lösungsmitteln / Recovery of Electrolyte Salts and Solvents), the project is funded by the German Federal Ministry of Economics and Climate Protection.
The project is supported by the lead partner Jülich; the consortium includes TU Dresden and Fuchs Schmierstoffe GmbH.
Due to the increased demand in Li-ion battery production in recent years, the raw material requirements for lithium, cobalt and other metals have also increased enormously. The costly extraction of these materials entails numerous ecological risks. Effective recycling of used batteries therefore represents an important sustainability factor for this technology.
While established recycling processes have focused predominantly on recovering the metals contained in LIBs, the SWELL project is addressing the recovery of the non-metallic components, i.e. the electrolytes, consisting of lithium salts, solvents and electrolyte additives, for the first time.
“The electrolytes are largely lost in previous processes in the form of thermal recycling or downcycling. However, the electrolyte components have significant material value and contain critical, environmentally relevant resources, such as lithium, fluorine and phosphorus. Their recovery and efficient reprocessing with the aim of direct reuse in LIBs is therefore of great interest and can lead to a significant increase in the sustainability of battery cell production”, states team member Dr. Kai Schwedtmann from the Chair of Inorganic Molecular Chemistry at Technische Universität Dresden.
The overall goal of the project is to develop processes in which a large part of the electrolyte components are selectively extracted, separated and then processed in order to integrate them back into a material cycle. The main focus here is on the electrolyte solvents (carbonates, such as DMC, EMC EC) and the lithium salt LiPF6 as well as its decomposition products.
To increase the material recovery rates during the recycling of LIBs, a team led by Prof. Jan J. Weigand at TU Dresden is working on efficient separation methods of liquid and solid electrolyte components.
“By developing and evaluating such a method, we aim to improve access to battery materials in Europe and reduce the environmental footprint of LIBs. We can achieve these goals by providing secondary components from cost-efficient processes in the future, thereby reducing dependencies along the battery value chain on non-European suppliers”, states TUD project manager Jan J. Weigand.