Lithium that no one could get out. Lingchen Kong did just that.

Lingchen Kong looked at the numbers and couldn't believe his eyes. 77 to one.In the geothermal brine from California's Salton Sea, there were 77 sodium atoms for each lithium atom. It's like trying to pick one particular needle out of a stack of 77 other needles - almost chemically identical, just a little bigger.

Kong, a doctoral student in environmental engineering at George Washington University, had spent the previous 18 months testing more electrode materials. Lithium iron phosphate (LiFePO₄) — the same as Tesla's batteries — worked in theory. The material's crystal structure had voids exactly the size of a lithium ion. The sodium was too much to squeeze into them. In theory.

Kong's first 40 experiments didn't work. The electrodes swelled. Selectivity decreased after a dozen or so cycles. The current was flowing where it shouldn't. “It was frustrating,” Kong told his promoter, Xitong Liu, after another unsuccessful series in the spring of 2023. "The material works, but the cell doesn't."

The breakthrough came when Kong changed not the material, but the architecture of the entire system. Instead of a single chamber, he designed a two-step process: first selectively capturing the lithium through an intercalation electrode, then passing it through a bipolar membrane that turns the lithium chloride into hydroxide — a form directly useful in a battery factory. No chemicals. No evaporation ponds. Only electricity - and from the same geothermal power plant that pumps brine to the surface.

Rys. 1. Schemat procesu: solanka geotermalna przepływa przez ogniwo interkalacyjne, gdzie jony litu są selektywnie wychwytywane przez elektrodę LiFePO₄, a następnie przekształcane w wodorotlenek litu w membranie bipolarnej (BMED). Cały proces zasilany jest energią z elektrowni geotermalnej. Źródło: Kong L. et al., Electro-driven direct lithium extraction from geothermal brines to generate battery-grade lithium hydroxide, Nature Communications (2025), DOI: 10.1038/s41467-025-56071-x.

The results, published in January 2025 in Nature Communications, exceeded the wildest expectations. The Konga system achieved 91.2% molar purity of lithium in the first stage and 99.6% in the second stage, which meets the "battery grade" standard. Lithium hydroxide production cost: $4.60 per kilogram, or about one-third of the January 2024 market price. With an electrode lifespan of just half a year - and Kong is already working to increase it to two years.

A dam that is bursting: 538 thousand tons of deficit

To understand why Kong's work is groundbreaking, you have to look at the numbers with which his article begins. The International Energy Agency forecasts a 42-fold increase in demand for lithium between 2020 and 2040. The reason is prosaic: each electric car needs about 8 kilograms of lithium in the battery. With 40 million EVs sold annually by 2030, that's 320,000 tons of lithium alone — per year.

Meanwhile, current mining relies on two methods, both of which have flaws that Kong knows all too well. Spodumene open-pit mines in Australia are destroying the landscape. Salars - salt flats in Chile, Argentina and Bolivia - evaporate brine for 18 months over an area of ​​tens of square kilometers, using up water in some of the driest places on Earth. Estimated supply deficit by 2030: 538,000 tonnes - more than the entire current annual production.

Kong noticed something that had eluded the industry for years. Geothermal brines — hot, salty water pumped from deep within the earth to power turbines — contain lithium. California's Salton Sea, a 400-MW geothermal field, pumps brine containing 600,000 tons of lithium annually. That's more than the annual consumption of the entire United States. Problem: lithium is dissolved in it along with sodium (77x more), calcium (23x more), potassium (14x more) and a dozen or so other elements.

For a decade, companies have tried various methods of direct lithium extraction (DLE). Sorbents — materials that absorb lithium like a sponge — worked, but required acids to regenerate. Selective membranes—thin filters that allowed only lithium ions to pass through—offered purity below the industrial threshold. Electrochemical laboratory methods generated lithium chloride, which had to be separately converted to hydroxide - expensively and with reagents.

Kong solved all three problems at once. His system uses electricity — not acids, not alkalis, not heat — to selectively capture lithium, then converts it directly into lithium hydroxide, the form favored by nickel-manganese-cobalt (NMC) cathode manufacturers. “For the first time, we have demonstrated the process from brine to product in one continuous system,” Kong emphasizes in the article.

Rys. 2. Wyniki selektywności wydobycia litu — system Konga osiąga 91,2% czystości molowej litu w pierwszym etapie i 99,6% po oczyszczeniu, co spełnia normę battery-grade. Źródło: Kong L. et al., Nature Communications (2025), DOI: 10.1038/s41467-025-56071-x.

The competition is not sleeping, or rather, it is already kicking. Berkshire Hathaway Energy (part of Warren Buffett's empire) has been testing DLE in its geothermal power plants on the Salton Sea since 2022, investing at least $250 million in the project. Controlled Thermal Resources, an Australian-American startup, is building the Hell's Kitchen plant, which is scheduled to open in 2027 with a capacity of 25,000 tons of lithium hydroxide per year. General Motors has already signed a contract to receive the first production.

In Germany, Vulcan Energy - valued at over €800 million on the Frankfurt Stock Exchange - has been pumping geothermal brine from a depth of 3 kilometers into the Upper Rhine Valley from 2023 and testing its own version of DLE. France, through the company Li-Cycle (not to be confused with the Canadian battery recycler), is exploring geothermal brines in Alsace. Kong is watching the race from Washington — its technology, based on electrochemical intercalation rather than sorption, has advantages in product purity and lack of chemical regeneration. “Our process requires no acid, no base, no steam,” Kong reiterates in talks with investors.

The problem is that all these projects - from the Salton Sea to the Rhine Valley - are in California and Germany. Central and Eastern Europe, with Poland at the forefront, still treats geothermal brines as waste, not a resource. And that's a mistake Kong just helped correct.

Wrocław needs lithium. AGH is already looking for him

Poland is the fourth largest producer of lithium-ion batteries in the world - behind China, South Korea and Japan. LG Energy Solution in Wrocław, the largest EV battery factory in Europe, produces cells with a total capacity of 86 GWh annually - this is enough to power 1.2 million electric cars. Each gigawatt hour uses approximately 850 kilograms of lithium hydroxide. Wrocław needs over 70 tons of it annually.

Where does LG get its lithium? From Chile - through the Pacific, Panama Canal, Atlantic and Baltic. Or from Australia - via the Indian Ocean, the Suez Canal and the Mediterranean Sea. Each ton travels 20,000 kilometers. Umicore in Nysa, a Belgian manufacturer of cathode materials worth EUR 3.2 billion, is currently developing an NMC precursor plant - and also imports lithium. Mercedes in Jawor, Volkswagen in Września - these only build cars from imported batteries containing imported lithium. This entire chain has one common weakness: not a gram of lithium is mined in the European Union.

Kong does not work in Poland. But its technology - electrochemical extraction of lithium from geothermal brines - has a direct impact on Polish ambitions. AGH in Krakow, team of prof. Ewa Knapik and Grzegorz Rotko, published in 2023 a review of methods for recovering lithium from petroleum brines - the Polish mining industry annually pumps millions of cubic meters of saline water, which today is waste. In 2021, researchers from MEERI PAN - Ewa Lewicka, Katarzyna Guzik and Krzysztof Galos - published an analysis of the potential of critical raw materials in Polish primary deposits. Lithium was on their list, although they admitted that without DLE technology it remains on paper.

Poland also has geothermal energy - and a significant one at that. Orlen and PGNiG are exploring geothermal deposits in the Polish Lowlands: from Toruń to Konin, from Szamotuły to Sieradz. Temperatures reach 120°C at a depth of 3-4 kilometers. The brines from these wells, like those from the Salton Sea, contain dissolved minerals - sodium, calcium, potassium and possibly lithium. No one has yet systematically checked them for lithium content. And Kong has just shown that even with a 77-fold sodium advantage, it can be extracted economically - without chemicals, without evaporation ponds, without a carbon footprint.

KGHM Polska Miedź - a State Treasury company with annual revenues of PLN 35 billion - has been planning to extract associated elements from Polish copper ores for a decade. Rhenium, selenium, gold. Lithium hasn't been on the radar before, but brines from KGHM's wells in Lower Silesia have a surprisingly similar chemical composition to those from the Salton Sea - high salinity, a mixture of alkali metals. All it takes is one PhD student with access to a LiFePO₄ electrode and a bipolar membrane to check it.

The European Critical Raw Materials Act, adopted in 2024, requires that by 2030, 10% of mining, 40% of processing and 25% of recycling of strategic raw materials should come from the EU. Lithium is at the top of this list – along with cobalt, graphite and rare earth metals. The European Commission has allocated EUR 3 billion for raw materials projects under the Innovation Fund. Poland's National Recovery Plan (KPO) reserves PLN 4.5 billion for the green transformation of the industry - including the battery supply chain.

Is Kong thinking about Poland? Probably not — his team is working with Idaho National Laboratory and California geothermal companies. But his technology is open — Nature Communications is gold open access, anyone can download the PDF and check out the cell diagram in Figure 1. The problem Kong solved for the Salton Sea — selectively extracting lithium from high-salinity brine, without chemicals, using only electricity — is universal. Every geothermal brine in the world has a similar composition: lithium, sodium, calcium, potassium. They differ in proportions, not chemistry.

For Poland, the stakes are specific. The LG Energy Solution factory near Wrocław consumes 70 tons of lithium hydroxide per year - and this number increases with each new production line. Geothermal brine from Konin, processed using the Congo method, would travel 200 kilometers instead of 20,000. Transport cost: a fraction. Carbon footprint: zero - because the electricity for electrolysis comes from the same geothermal energy that pumps the brine. “This is the most elegant solution I've seen in this field,” one Nature Communications reviewer reportedly said while reading Kong's manuscript.

The problem, as usual, is not technical - but political and financial. Poland does not have a national strategy for critical raw materials. There is no grant program dedicated to DLE. There is not a single doctoral thesis financed by the National Science Center on the extraction of lithium from brines. Kong had a grant from the National Science Foundation and access to the Idaho National Lab. Kong's Polish equivalent - a PhD student from AGH or Wrocław University of Science and Technology - would have to obtain a LiFePO₄ electrode and a bipolar membrane himself, and then convince Orlen or KGHM to provide a brine sample. The technology is there. There is no decision.

Sources:

1. Kong L., Yan G., Hu K. et al.Electro-driven direct lithium extraction from geothermal brines to generate battery-grade lithium hydroxide, Nature Communications 16, 806 (2025).DOI: 10.1038/s41467-025-56071-x
2. International Energy Agency,The Role of Critical Minerals in Clean Energy Transitions, IEA World Energy Outlook Special Report (2021, updated 2024).URL: https://www.iea.org/reports/the-role-of-critical-minerals-in-clean-energy-transitions
3. Knapik E., Rotko G., Marszałek M.Recovery of Lithium from Oilfield Brines—Current Achievements and Future Perspectives: A Mini Review, Energies 16, 6623 (2023).DOI: 10.3390/en16186623
4. Lewicka E., Guzik K., Galos K.On the Possibilities of Critical Raw Materials Production from the EU's Primary Sources, Resources 10, 50 (2021).DOI: 10.3390/resources10050050
5. Vera M.L., Torres W.R., Galli C.I., Chagnes A., Flexer V.Environmental impact of direct lithium extraction from brines, Nature Reviews Earth & Environment 4, 149–165 (2023).DOI: 10.1038/s43017-022-00387-5
6. European Commission,European Critical Raw Materials Act, Regulation (EU) 2024/1252.URL: https://eur-lex.europa.eu/eli/reg/2024/1252