What’s behind lithium mining? Here’s all you need to know

Demand is growing across the globe for lithium extraction, mainly driven by the increasing use of lithium in electronic battery technologies and electric vehicles. But where does lithium come from and how is it produced? Here’s an explainer with everything you should know, including the environmental impacts.

Hexagonal formations on the surface of the Salar de Uyuni as a result of salt crystallization from evaporating water. Credit Wikimedia Commons

Basically, lithium is a highly reactive alkali metal with excellent heat and electrical conductivity. Such characteristics make it especially useful to manufacture lubricants, pharmaceuticals, glass and, most importantly, lithium-ion batteries for electric cars and consumer electronics.

But lithium can’t just be found in nature, as it’s highly reactive. Instead, it’s present as a constituent of salts or other compounds. Most of the lithium available in the market can be found as lithium carbonate, a more stable compound that can then transformed into chemicals or salts.

Lithium salts can be found in underground deposits of clay, mineral ore and brine, as well as in geothermal water and seawater. Most of the world’s lithium comes from mines, from where it’s extracted. Briny lakes, also known as salars, have the highest concentration of lithium, ranging from 1,000 to 3,000 parts per million.

Lithium extraction

A Taiwanese Monk at the Salar of Uyuni during winter. Photo taken at sunset time. He was travelling for a few weeks in order to see some nice places and to meet some of his fellows scattered in Latin America. Credit: Christopher Crouzet, Wikimedia Commons.

The salars with the highest lithium concentrations are located in Bolivia, Argentina, and Chile, in an area called “the lithium triangle.” Lithium obtained from salars is then recovered in the form of lithium carbonate, the main raw material that is used by companies in lithium-ion batteries.

Brine mining in salars is normally a very long process that can take from eight months to three years. Mining starts by drilling a hole and pumping brine to the surface. Then they leave it to evaporate for months, first creating a mix of manganese, potassium, borax, and salts which is filtered and placed into another evaporation pool.

Salt mounds in Salar de Uyuni, Bolivia. The Salar de Uyuni is the world’s largest (12 000 km²) and highest (3 700 m) salt flat, ca. 25 times as large as the Bonneville Salt Flats. It’s the remnant of a prehistoric lake surrounded by mountains without drainage outlets. Credit: Luca Galuzzi, Wikimedia Commons.

It will take between 12 and 18 months for that mix to be filtered enough in order to be able to extract the lithium carbonate, also known as white gold. While it’s cheap and effective, the process needs a lot of water, estimated at 500.000 gallons per ton of lithium extracted.

This creates a lot of pressure in local communities living in nearby areas. For example, in Chile’s Salar de Atacama, mining has caused the region to lose 65% of the region’s water. This has meant impacts of local farmers, who rely on agriculture and cattle for their livelihoods and now need to get the water from somewhere else.

The risks of lithium mining

Lack of water in the region is not just the single potential problem with lithium mining. Toxic chemicals can leak from the evaporation pools to the water supply, such as hydrochloric acid, which is used in the processing of lithium – as well as waste products that can filter out of the brine.

In the United States, Canada, and Australia, lithium is usually extracted from the rock by using more traditional methods. Nevertheless, this still requires the use of chemicals in order to extract it in a useful form. In Nevada, the research found impacts on fish 150 miles downstream from a lithium processing operation, for example.

A report by Friends of the Earth argued that extracting lithium can affect the soil and causes air contamination. In the area Salar del Hombre Muerto in Argentina, residents complain that lithium polluted streams that are used by humans and livestock, while in Chile there were clashes between mining firms and locals.

Improved technologies for lithium extraction

Researchers argue that there’s a need to develop new extraction technologies that can allow manufacturing batteries in a more environmentally friendly way. That’s why across the world many are looking for new alternatives, such as battery chemistries that replace cobalt and lithium with more common and less toxic materials.

Nevertheless, new batteries that are less energy-dense or more expensive could end up having a negative effect on the environment. “A less durable, yet more sustainable device could entail a larger carbon footprint once you factor in transportation and the extra packaging required,” said Christina Valimaki an analyst at Elsevier.

Being able to recycle lithium-ion plays a key role as well. In Australia, research showed that only 2% of the country’s 3,300 tons of lithium-ion waste was recycled. That can cause problems, as unwanted electronics with batteries can end up in landfills and metals and ionic fluids can leak into underground water reservoirs.

The Birmingham Energy Institute is using robotics technology initially develop for nuclear power plants to look for ways to remove and dismantle potentially explosive lithium-ion cells from electric vehicles. There were a number of fires at recycling plants where lithium-ion batteries have been stored improperly.

A key problem is that manufacturers are usually secretive regarding what actually goes into the batteries, which makes it difficult to recycle them properly. Now, recovered cells are mostly shredded, leading to a mixture of metals that can be separated using pyrometallurgical techniques.

Growing demand

Credit: Public Domain.

The global enchantment over mobile devices and all kinds of technological gadgets have led to a growing demand for lithium-ion batteries. That’s especially applicable for electric vehicles, as the world seeks to stop using fossil fuels in the near future to reduce global greenhouse gas emissions.

By 2025, lithium demand is expected to increase to approximately 1.3 million metric tons of LCE (lithium carbonate equivalent). That’s five times today’s levels. A long list of automakers is responsible for that. For example, Volkswagen hopes to launch more than 70 electric car models in the next 10 years.

The growth in demand for lithium can also be linked to an announcement made by China in 2015, prioritizing electric vehicles as part of its five-year plan. Over the period from 2016 to 2018, lithium prices have more than doubled and are expected to keep growing as the demand expands.

The open question is the consequences that such demand will have on the environment and the communities near the salt mines where the lithium is extracted. The more gadgets and electric vehicles the more lithium that will be needed in the future, raising the need to develop more environmentally friendly extraction techniques.

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