Optimization of processing costs could improve the cost-competitiveness of lithium extraction from clay relative to conventional sources of brines and hard rock ores

Lithium is a critical material for current and future battery technologies. Commercial production primarily relies on hard rock deposits (e.g., in Australia, China, Zimbabwe) and brines (e.g., in Chile, Argentina). This study evaluates the economic viability of lithium extraction from clay, the third largest lithium resource globally, by analyzing seven proposed projects employing three different extraction technologies: Hydrochloric acid leaching, sulfuric acid leaching, and sulfate salt roasting. We benchmark levelized production costs for clay extraction against global brine and hard rock extraction operations and projects (4996-5580 USD t−1 LCE). Our findings indicate that clay-based lithium extraction can be between 20% and 100% more expensive than global averages, depending on extraction technology and process flow (6429-10,875 USD t−1 LCE). However, we propose pathways that can improve cost-competitiveness relative to conventional sources by up to 50%. We emphasize that these are modeled optimization pathways derived from feasibility-stage data and have not yet been demonstrated at commercial scale. Lithium from clay currently costs 20–100% more than brine or hard rock, but reductions in reagent, power, and capital costs could narrow the gap, according to process-level cost modeling of seven feasibility-stage projects across three extraction routes. Primary Handling Editors: I-Yun Hsieh and Alireza Bahadori.