How Pure Lithium Brine to Battery Technology Improves Energy Storage, Manufacturing

Pure Lithium’s Brine to Battery™ technology fundamentally changes the way rechargeable batteries are made, from the materials used to the methods of production. The result is a lithium-metal (Li-M) battery delivered at a lower cost with significantly higher energy density than lithium-ion (Li-ion), the dominant battery on the global market today. The Brine to Battery method turns lithium-containing brines into 99.9% pure, battery-ready Li-M anodes, using sophisticated electrochemistry. This method has been successfully demonstrated with global low-grade brines, opening opportunities into untapped North American resources, such as oilfield and geothermal wastewater. 

The Brine to Battery method enables co-location of brine feedstock, extraction facility, and manufacturing facility – dramatically cutting transportation costs and emissions. Pure Lithium’s first generation batteries are lab-scale pouch cells using Brine to Battery anode and commercial LFP cathode which have demonstrated more than 5,500 cycles at 100% depth of discharge, cycled at a rate of 1C:1C while retaining >90% nameplate capacity. This Li-M battery has twice the capacity and half the weight of an equivalent Li-ion battery and is about 30% less expensive in material costs alone. Pure Lithium aims to create the first closed-loop supply chain for rechargeable batteries in the United States. 

Li-ion batteries are outdated and unsuitable for meeting growing global energy demand. Less than 5% of Li-ion batteries are recycled and the Li-ion anode offers a maximum theoretical energy density of only 372 mAh/g. In contrast, the Li-M anode offers 10 times the maximum theoretical energy density, at 3860 mAh/g, and is designed for recyclability, as a pure, non-composite material. The high energy density properties of Li-M have been known for decades, but a commercially viable Li-M battery has never been produced due to (1) expensive, unreliable production methods, and (2) unsustainable, uneconomic supply chains. Lithium is traditionally extracted from brines in South America, using open-air or direct lithium extraction (DLE), methods that waste an unacceptable amount of freshwater. This precursor Li salt is transported to China, where molten salt electrolysis is used to produce a Li-M ingot. Molten salt electrolysis requires near-stoichiometric amounts of KCl, operates at >400°C, and emits chlorine gas. The resulting Li-M ingot can be turned into Li-M anodes using physical vapor deposition (PVD) or ingot extrusion. PVD is energy-intensive and expensive, while ingot extrusion uses high pressures and produces inconsistent quality foils that are easily damaged in transport. Both methods result in an anode that delaminates from its substrate when cycled as a battery – completely unsuitable for Li-M battery applications. The lithium supply chain alone covers approximately 55,000 nautical miles, equivalent in emissions to 805 kg CO2 per tonne of cargo. Not included in this calculation is graphite, the primary material making up the Li-ion anode, which is produced primarily in China. Nor the cathode side which typically requires Cobalt, Nickel, and Manganese – materials that rely on mining practices that are unsustainable and harmful to human health.  It takes 587 days for lithium to get from the ground into a Li-ion battery via conventional methods and supply chains, while the Brine to Battery™ method takes 48 hours. Pure Lithium’s Li-M battery can be used in any application that currently relies on Li-ion batteries, including consumer electronics, drones, electric vehicles and grid scale energy storage.