Life cycle carbon footprint of novel technologies for lithium production and potential implications for the supply chain in North America

• Novel technologies show promise to reduce lithium’s carbon footprint. • Estimated potential carbon footprints of 2–18 kgCO₂e/kg (no allocation). • Carbon footprint is influenced by energy and chemical sources, and LCA methods. • Compared Li and Na-ion batteries carbon footprints with different functional units. • Conclusions may vary based on the functional unit when assessing battery impacts. This study explores unconventional lithium sources in North America for producing lithium hydroxide monohydrate (LiOH.H 2 O) with lower greenhouse gas (GHG) emissions compared to traditional sources. We also estimate how batteries using LiOH.H 2 O would compare with the emerging sodium-ion battery technology. Novel technologies (e.g., direct lithium extraction, DLE, and electrochemical refining) show promise to reduce GHG emissions compared to traditional methods, with carbon footprints from 2 to 18 kgCO 2 eq/kg LiOH.H 2 O (baseline, no allocation). Electricity carbon intensity and methodological choices (e.g., co-product allocation/substitution, boundary definitions) are the most influential factors across pathways, with impacts ranging from -156 % to 130 % in carbon footprints relative to baseline scenarios. Furthermore, while unconventional lithium sources coupled with novel processing technologies may reduce carbon footprints compared to current incumbent pathways, research and development (R&D) and innovation effects should be considered to maintain competitiveness in the face of other emerging technologies, such as sodium-ion batteries.