Lithium

Lithium (from Ancient Greek: λίθος, líthos, 'stone') is a chemical element; it has symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid element. Like all alkali metals, lithium is highly reactive and flammable, and must be stored in vacuum, inert atmosphere, or inert liquid such as purified kerosene or mineral oil.

Lithium has important uses in nuclear physics, including being used in early nuclear reaction experiments and serving as fusion fuel in staged thermonuclear weapons. It also has many industrial applications, such as in heat-resistant glass and ceramics, lithium grease lubricants, and especially in lithium metal batteries and lithium-ion batteries, which use most of the world's lithium production.

Lithium is also used in medicine. Lithium-based drugs help treat mental illness such as bipolar disorder by acting as a mood stabilizer and antidepressant. Though it is rare in nature, lithium can be found in small amounts in ocean water and is extracted from certain minerals and brines.

Properties

Lithium is a soft, silvery-white metal that belongs to a group called the alkali metals. It is very light—it’s the least dense metal and can even float on water! Like other alkali metals such as sodium and potassium, lithium has one outer electron that it easily shares, making it a good conductor of heat and electricity.

Lithium has some interesting properties. It can be cut with a knife and changes when exposed to air. It melts at a temperature of 180.50 °C and boils at a very high 1,342 °C. Lithium is also used in coolants because it can absorb a lot of heat. There are two main types of lithium found in nature, called isotopes, which have slightly different weights.

Occurrence

Lithium-7 was created in the early universe in a process called Big Bang nucleosynthesis. It is found in space, including in brown dwarf stars, and its presence helps scientists tell different types of stars apart. On Earth, lithium is not found in its pure form because it reacts easily with other elements. It is found in small amounts in seawater, in certain rocks like granites, and in minerals such as spodumene and petalite. Chile has the largest known reserves of lithium, and Australia produces the most each year.

See also: Lithium compounds and Lithium minerals

Lithium is present in tiny amounts in plants, animals, and even human bodies, though it is not known to play a special role in living things. It is absorbed by plants and can be found in foods such as potatoes and tomatoes. Lithium behaves similarly to sodium and magnesium in the body, affecting how cells work, but its exact effects in living organisms are still being studied.

History

Petalite was discovered in 1800 by Brazilian chemist José Bonifácio de Andrada e Silva in a mine on the island of Utö, Sweden. In 1817, Johan August Arfwedson, working in the laboratory of chemist Jöns Jakob Berzelius, detected a new element in petalite ore. This element formed compounds similar to sodium and potassium. Berzelius named it "lithium," from the Greek word for "stone," because it was found in a solid mineral.

Later, Arfwedson found the same element in minerals called spodumene and lepidolite. In 1818, Christian Gmelin observed that lithium salts give a bright red color to flame. It wasn’t until 1821 that William Thomas Brande isolated pure lithium using electrolysis of lithium oxide. In the mid-20th century, lithium began to be used to treat mood disorders, and during World War II and the Cold War, it was important for making aircraft engine greases and later for nuclear weapons. Today, lithium is widely used in lithium-ion batteries, which has increased demand for the element.

Chemistry

Lithium is a very reactive metal. It can react with water to make hydrogen gas and lithium hydroxide. When you put lithium near a flame, it can turn a bright red color. Lithium needs special storage to keep it from reacting with air or water.

Lithium makes many useful compounds. One important compound is lithium carbonate, which comes from lithium ores and helps make batteries and other materials. Organolithium compounds are special chemicals used in making medicines and other important substances in laboratories. They are very reactive and can catch fire when they touch air.

Production

See also: List of countries by lithium production

Lithium production has grown a lot since the end of World War II. The main sources of lithium are brines and ores.

Lithium metal is made through electrolysis using a mix of 55% lithium chloride and 45% potassium chloride at about 450 °C.

Lithium is important for renewable energy and batteries, which means it will likely be in high demand. The world has about 26 to 28 million tonnes of identified lithium reserves, but measuring these reserves can be tricky.

The US Geological Survey estimated worldwide identified lithium reserves in 2022 and 2023 to be 26 million and 28 million tonnes, respectively. An accurate estimate of world lithium reserves is difficult. One reason for this is that most lithium classification schemes are developed for solid ore deposits, whereas brine is a fluid that is problematic to treat with the same classification scheme due to varying concentrations and pumping effects.

In 2019, world production of lithium from spodumene was around 80,000 t per annum, primarily from the Greenbushes pegmatite and from some Chinese and Chilean sources. The Talison mine in Greenbushes is reported to be the largest and to have the highest grade of ore at 2.4% Li₂O (2012 figures).

The world's top four lithium-producing countries in 2019, as reported by the US Geological Survey, were Australia, Chile, China and Argentina.

The three countries of Chile, Bolivia, and Argentina contain a region known as the Lithium Triangle. The Lithium Triangle is known for its high-quality salt flats, which include Bolivia's Salar de Uyuni, Chile's Salar de Atacama, and Argentina's Salar de Arizaro. As of 2018, the Lithium Triangle had been estimated to contain over 75% of then known lithium reserves. Deposits found in subsurface brines have also been found in the United States (southwest Texas and Arkansas) and South America throughout the Andes mountain chain. In 2010, Chile was the leading producer, followed by Argentina. Both countries recover lithium from brine pools. According to USGS, Bolivia's Uyuni Desert has 5.4 million tonnes of lithium. Half the world's known reserves as of 2022 were located in Bolivia along the central eastern slope of the Andes. The Bolivian government invested US$900 million in lithium production by 2022, and in 2021 successfully produced 540 tons. The brines in the salt pans of the Lithium Triangle vary widely in lithium content. Concentrations can also vary over time as brines are fluids that are changeable and mobile.

Extracting lithium from brine deep in Wyoming's Rock Springs Uplift has been proposed as revenue source to make atmospheric carbon sequestration economically viable. Additional deposits in the same formation were estimated to be as much as 18 million tons if economic means of recovery can be employed. Similarly in Nevada, the McDermitt Caldera hosts lithium-bearing volcanic muds that consist of the largest known deposits of lithium within the United States.

In the US, lithium is recovered from brine pools in Nevada. Projects are also under development in Lithium Valley in California and from brine in southwest Arkansas using the direct lithium extraction process, drawing on the deep brine resource in the Smackover Formation.

A deposit of Rotliegend lithium brines containing 43 million tons of lithium carbonate equivalent was discovered in the Altmark region of Saxony-Anhalt, Germany, in 2025, potentially eliminating the dependency of European electric vehicle battery producers on imported lithium.

Since 2018 the Democratic Republic of Congo is known to have the largest lithium spodumene hard-rock deposit in the world. The deposit located in Manono, DRC, may hold up to 1.5 billion tons of lithium spodumene hard-rock. The two largest pegmatites (known as the Carriere de l'Este Pegmatite and the Roche Dure Pegmatite) are each of similar size or larger than the famous Greenbushes Pegmatite in Western Australia. Thus, the Democratic Republic of Congo is expected to be a significant supplier of lithium to the world with its high grade and low impurities.

On 16 July 2018 2.5 million tonnes of high-grade lithium resources and 124 million pounds of uranium resources were found in the Falchani hard rock deposit in the region Puno, Peru. In 2020, Australia granted Major Project Status (MPS) to the Finniss Lithium Project for a strategically important lithium deposit: an estimated 3.45 million tonnes (Mt) of mineral resource at 1.4 percent lithium oxide. Operational mining began in 2022.

The Pampean Pegmatite Province in Argentina is known to have a total of at least 200,000 tons of spodumene with lithium oxide (Li₂O) grades varying between 5 and 8 wt %.

In Russia the largest lithium deposit Kolmozerskoye is located in Murmansk region. In 2023, Polar Lithium, a joint venture between Nornickel and Rosatom, has been granted the right to develop the deposit. The project aims to produce 60,000 tonnes of lithium carbonate and hydroxide per year and plans to reach full design capacity by 2030.

Another potential source of lithium as of 2012 was identified as the leachates of geothermal wells, which are carried to the surface. Recovery of this type of lithium has been demonstrated in the field; the lithium is separated by simple filtration. Reserves are more limited than those of brine reservoirs and hard rock.

Prices for lithium carbonate in 2024 were in the range of $10,000/ton.

Lithium and its compounds were historically isolated and extracted from hard rock. However, by the 1990s mineral springs, brine pools, and brine deposits had become the dominant source. Most of these were in Chile, Argentina and Bolivia and the lithium is extracted from the brine by evaporative processes. Large lithium-clay deposits under development in the McDermitt caldera (Nevada, United States) require concentrated sulfuric acid to leach lithium from the clay ore.

By early 2021, much of the lithium mined globally came from either "spodumene, the mineral contained in hard rock formations found in places such as Australia and North Carolina" or from salty brine pumped directly out of the ground, as it is in locations in Chile, Argentina, and Arkansas.

In Chile's Salar de Atacama, the lithium concentration in the brine is raised by solar evaporation in a system of ponds. The enrichment by evaporation process may require up to one-and-a-half years, when the brine reaches a lithium content of 6%. The final processing in this example is done in Salar del Carmen and La Negra near the coastal city of Antofagasta where pure lithium carbonate, lithium hydroxide, and lithium chloride are produced from the brine.

Direct Lithium Extraction (DLE) technologies are being developed as alternatives to the evaporitic technology long used to extract lithium salts from brines. The traditional evaporitic technology is a long duration process requiring large amounts of land and intensive water use, and can only be applied to the large continental brines. In contrast, DLE technologies are proposed to tackle the environmental and techno–economic shortcomings by avoiding brine evaporation. Some recent lithium mining projects in the United States are attempting to bring DLE into commercial production by these non-evaporative DLE approaches.

One method of direct lithium extraction, as well as other valuable minerals, is to process geothermal brine water through an electrolytic cell, located within a membrane.

The use of electrodialysis and electrochemical intercalation was proposed in 2020 to extract lithium compounds from seawater (which contains lithium at 0.2 parts per million). Ion-selective cells within a membrane in principle could collect lithium either by use of electric field or a concentration difference. In 2024, a redox/electrodialysis system was claimed to offer enormous cost savings, shorter timelines, and less environmental damage than traditional evaporation-based systems.

Applications

Batteries

In 2021, 87% of the world’s lithium production was used to make lithium-ion batteries for electric cars and mobile devices. Lithium is important for batteries because it has a high electrode potential. Its low atomic mass gives it a great power-to-weight ratio. A typical lithium-ion battery can generate about 3 volts per cell, more than lead-acid or zinc-carbon batteries.

Ceramics and glass

Lithium oxide is used to make ceramics and glass. It lowers the melting point and viscosity of materials, helping create better glazes. Lithium carbonate is often used for this purpose.

Lubricating greases

Lithium is the third most common use in greases. Lithium hydroxide creates a soap when heated with fats, which thickens oils. This is used to make high-temperature lubricating greases.

Metallurgy

Lithium is added to metals to change their properties. It helps make molten metals flow better and is used in aluminium production to lower melting temperatures. Alloys of lithium with metals like aluminium are used in aircraft parts.

Pyrotechnics

Lithium compounds give red color to fireworks and flares.

Air purification

Compounds like lithium chloride and lithium bromide are used to remove moisture from air. Aboard spacecraft and submarines, lithium hydroxide removes carbon dioxide.

Optics

Lithium fluoride is used in special glasses and lenses for cameras and telescopes. It works well for seeing ultraviolet light.

Organic and polymer chemistry

Organolithium compounds are important in making plastics and chemicals. They help create new molecules and are used as catalysts.

Medicine

Lithium helps treat bipolar disorder. It is used to balance mood and prevent extreme emotions. Lithium salts are known as mood stabilizers.

Precautions

Lithium metal is corrosive and needs careful handling to prevent skin contact. Inhaling lithium dust or certain lithium compounds can irritate the nose and throat, and in larger amounts, may affect the lungs. The metal itself can be dangerous if it touches water, as it forms lithium hydroxide, a caustic substance. To keep it safe, lithium metal is stored in materials like naphtha that won’t react with it.