In Germany, the geothermal waters in the North German Basin (NDB) and Upper Rhine Valley (ORG) have been confirmed as having some of the world’s highest concentrations of lithium (NDB: up to 240 mg/L, Regenspurg et al. 2015; ORG: 100-200 mg/L, Sanjuan et al. 2016). Given both the lithium concentrations and volumes of geothermal water fluids in these regions, Germany has good potential for the extraction of lithium from geothermal waters. Gaining commercial value from lithium extraction can potentially provide additional revenue streams to geothermal energy plants and contribute developing domestic supply chain of lithium for batteries, in Germany. Furthermore, the use of direct lithium extraction (DLE) technologies enables a more sustainable lithium supply compared to conventional solar evaporation pond and hard rock mining methods, in terms of land use, water use and carbon emissions. ....