The material necessary for the electromobile industry can be found where there have been catastrophic super-eruptions in antiquity.
As scientists from the United States have established, rubidium impurities in salts on the site of ancient eruptions of supervolcanoes mean that they contain a lot of lithium. Such salts are many near the places of ancient eruptions of American super volcanoes. This will greatly facilitate the search for new sources of this material, the consumption of which has been growing unusually fast in recent years. The corresponding article is published in Nature Communications.
At present, world consumption of lithium is experiencing extremely rapid growth. If in 2016 less than half a million electromobiles were produced, then in 2018, according to forecasts, they will be made about a million, and by 2020 – about one and a half million. A number of industry observers say that by the 2030s they will be made several tens of millions each year. Meanwhile, lithium for batteries is still produced only from deposits in place of salt lakes in Latin America and in smaller quantities in Australia. The manufacturers of batteries face a real threat of a shortage of raw materials. In theory, it can be extracted from sea water, but extraction from salt deposits is slightly cheaper. Because of this, geologists around the world are looking for new sources of lithium.
Researchers analyzed the chemical composition of salt deposits in place of caldera lakes. Caldera is a volcanic basin with steep walls and a flat bottom. It is formed on a volcano after the collapse of the walls of the crater or as a result of its catastrophic eruption. Then it is filled with rainwater, washing away salts from igneous rocks and redepositing them along the shores of formed lakes. The authors found that lithium is the most abundant in those calderas where acidic igneous rocks were found during the eruption. Their high content is typical for the North American caldera formed on the site of the eruption of the Cenozoic supervolcanic eruptions, such as the Yellowstone.
The more salt deposits in such areas of rubidium and its compounds, the higher the content of lithium in them. On the contrary, a high content of zirconium indicates that lithium in such salts will be few. The information on these “fellow-travelers”, together with the indication of the prospect of searching for calves in the super volcanoes, will greatly simplify the search for new sources of lithium, which is in high demand with the industry.