Lithium is produced through two primary methods: pumping salt-rich brine from underground deposits and evaporating it in the sun, or mining a hard rock mineral called spodumene and processing it with heat and chemicals. Australia leads global production at 86,000 metric tons in 2023 using hard rock mining, while Chile produced 44,000 metric tons almost entirely from brine. China, Argentina, and Brazil round out the top five producers.
Brine Evaporation: Sun Does the Heavy Lifting
Beneath salt flats in South America, particularly in Chile and Argentina, massive underground reservoirs hold water saturated with dissolved minerals, including lithium. Producers pump this brine to the surface and channel it into a series of shallow evaporation ponds, where the sun and wind slowly drive off the water over many months.
The process works because different salts crystallize and drop out of the solution at different concentrations. As the brine moves through a sequence of roughly five ponds, common table salt precipitates first, followed by potassium-bearing salts, then magnesium compounds. Each pond removes a different impurity, leaving behind an increasingly lithium-rich solution. The potassium salts recovered along the way are valuable on their own and often sold as fertilizer. After the final evaporation stage, the concentrated lithium solution is piped to a refining plant, where it’s treated with chemicals to produce lithium carbonate, a white powder that serves as the starting material for most lithium products.
Brine operations are relatively low-energy since sunlight provides the evaporation power. They also tend to produce a smaller carbon footprint than hard rock mining. Research published in Nature Communications found that South American brine operations cluster at the low end of carbon emissions, roughly one-third the level of typical spodumene operations. The tradeoff is water: brine extraction consumes approximately 500 tons of water for every ton of lithium produced, and in the arid regions where these salt flats exist, that draw can strain neighboring water systems.
Hard Rock Mining: Heat and Acid
Australia dominates lithium production using a completely different approach. There, lithium is locked inside spodumene, a mineral found in large rock formations called pegmatites. Conventional open-pit mining extracts the ore, which is then crushed and processed in a concentrator to separate spodumene crystals from surrounding rock.
The raw spodumene concentrate can’t release its lithium easily because the mineral’s crystal structure is too tight and stable. To break it open, producers heat it to around 1,100°C for about two hours in a kiln. This transforms the mineral into a more porous form that chemicals can penetrate. The converted material is then mixed with sulfuric acid and baked again at around 250°C, which swaps lithium out of the crystal structure and into a water-soluble compound. From there, the lithium is dissolved in water, purified through a series of chemical steps, and converted into lithium carbonate or lithium hydroxide.
This route is faster than brine evaporation, taking days rather than months, but it’s energy-intensive. The high-temperature kilns burn significant fuel, and the carbon footprint per kilogram of lithium is roughly three times higher than brine-sourced lithium. Hard rock mining also generates waste rock and chemical byproducts that require careful management.
Lithium Carbonate vs. Lithium Hydroxide
Both brine and hard rock operations typically produce lithium carbonate first. This compound works for many battery types, but the fastest-growing segment of the battery market, nickel-rich cathode chemistries used in electric vehicles, requires lithium hydroxide instead. Lithium hydroxide is made by reacting lithium carbonate with calcium hydroxide, then purifying the result through additional refining steps to reach battery-grade purity. Some newer spodumene operations skip the carbonate stage entirely and convert directly to hydroxide, which cuts out a processing step and reduces cost.
Clay Deposits: A Newer Source
A third type of lithium source is gaining attention: sedimentary clay deposits, like those at the Thacker Pass project in Nevada. These clays contain lithium trapped inside layered mineral structures rather than dissolved in brine or locked in hard crystalline rock.
Extracting lithium from clay involves heating the material to around 600°C to break down the mineral phases, then soaking the heated clay in acid. The acid releases hydrogen ions that swap places with lithium ions in the clay’s layered structure, pulling lithium into solution. Under optimized lab conditions, this approach has achieved recovery rates above 91%. Clay deposits are abundant and found in more locations than traditional brine or spodumene sources, which makes them attractive for diversifying supply. However, commercial-scale production from clay is still in its early stages.
Recycling Spent Batteries
As billions of lithium-ion batteries reach the end of their useful life, recycling is becoming a meaningful production source. Two main approaches exist.
Pyrometallurgical recycling, the simpler method, feeds whole battery cells into a high-temperature furnace. The batteries melt and separate into two layers: heavy metals like cobalt and nickel sink to the bottom, while lighter materials including lithium float to the top in a slag layer. The problem is that lithium ends up mixed into the slag and is difficult to recover efficiently. This method loses a significant portion of the lithium and produces substantial emissions.
Hydrometallurgical recycling takes a more targeted approach. Battery materials are first shredded and sorted, then dissolved in chemical solutions that selectively pull out individual metals. Lithium ions in solution are separated through techniques like chemical precipitation or solvent extraction, then converted into lithium carbonate ready for reuse in new batteries. This method is more energy-efficient for lithium recovery, though it requires careful handling of the chemical solutions involved.
Where Production Is Headed
Global lithium production is concentrated in a small number of countries. According to U.S. Geological Survey data, seven mining operations in Australia, two brine operations each in Chile and Argentina, and a mix of six operations in China account for the majority of world output. The geographic concentration has pushed governments in the U.S. and Europe to develop domestic sources, including clay deposits and a newer technique called direct lithium extraction, which pulls lithium from brine chemically rather than waiting months for evaporation. These technologies aim to shrink both the timeline and the water footprint of brine-based production, though they haven’t yet reached the scale of conventional methods.