General Motors to Source Lithium for EV Batteries From the Salton Sea Region in California With New Strategic Partnership

author: Eric Walz   

The Salton Sea region in California is rich in lithium deposits, a key raw material for EV batteries.

Some industry analysts say that lithium is the "new oil", as the auto industry begins its transition to fully-electric cars. Lithium is a core raw material for the production of lithium-ion EV batteries and automakers are pursuing supply deals to ensure they have steady supply of raw materials to manufacture millions of electric vehicle batteries. The latest strategic partnership is from General Motors.

GM is forming a strategic investment and commercial collaboration with lithium producer Controlled Thermal Resources (CTR) to secure local and low-cost lithium in Southern California in the Salton Sea region. 

GM said its investment will help support CTR's more environmentally friendly direct extraction process to recover lithium from geothermal brine. 

This lithium produced for GM by CTR will be a closed-loop, direct extraction process that results in a smaller physical footprint and lower carbon dioxide emissions compared to traditional processes like pit mining or evaporation ponds.

Having a steady supply of lithium is crucial to GM's bold plans to phase out combustion engine passenger vehicles by 2035. The strategic partnership between GM and CTR is expected to accelerate the adoption of more environmentally friendly lithium extraction methods, which can help bring down the cost of producing batteries and make electric vehicles more affordable.

Lithium is a key battery material used in the cathodes and electrolytes of EV batteries. GM says that sourcing large amounts of lithium will become even more important for batteries in the future, as the automaker explores the use of more energy-dense, lithium metal batteries with a protected anode (Li-metal anode).

CTR has developed and managed world-scale renewable energy projects in the Salton Sea region of California for the past 20 years where large lithium deposits are found underground. The company was established in 2013 and has headquarters in Imperial Valley, California and Brisbane, Australia. 

How Lithium is Typically Extracted

Most lithium used in lithium-ion batteries is currently mined and processed outside of the U.S.

In South America, where some of the world's largest Lithium deposits are located, miners drill a hole in vast salt flats, which are actually ancient dried up lake beds. Deep underneath the salt layer is a brine that is rich in lithium salts. 

To extract the lithium from the brine, which is the world's lightest metal, massive amounts of water are pumped underground forming large pools. The water forces the mineral rich brine to the surface. These large pools of water containing the lithium are then left to evaporate in the sun. The process is similar to how sea salt is extracted from sea water.

After several months of evaporation in the hot sun, the brine leaves behind a dried mixture containing a mixture of manganese, potassium, borax and lithium, which is then filtered and placed into a separate evaporation pool. 

The process is repeated for up to two years until the mixture is filtered enough that the raw lithium carbonate can be extracted. This is the material used in the cathode and the electrolyte of EV batteries.

The standard Lithium extraction process uses approximately 500,000 gallons of water per metric ton of Lithium extracted. To put that in perspective, the Tesla Model S battery pack contains roughly 10 kilograms (22 lbs) of lithium.

CTR's closed-loop, direct lithium extraction process is done in a factory in a more sustainable process and doesn't use evaporation ponds or open pit mining. 

According to GM, a significant amount of the automaker's future battery-grade lithium and carbonate could be sourced from CTR's Hell's Kitchen Lithium and Imperial Valley Geothermal Project Power, which is also known as the "Salton Sea Geothermal Field" in Imperial, California.

The Salton Sea Geothermal Field, comprises 11 geothermal power stations located along the shore of the Salton Sea. It's the second largest geothermal field in the U.S. and is rich with natural lithium deposits.

The region has the potential to supply 40% of global lithium demand, according to David Hochschild, Chair, California Energy Commission.

"Lithium is critical to battery production today and will only become more important as consumer adoption of EVs increases, and we accelerate towards our all-electric future," said Doug Parks, GM executive vice president, Global Product Development, Purchasing and Supply Chain. "By securing and localizing the lithium supply chain in the U.S., we're helping ensure our ability to make powerful, affordable, high mileage EVs while also helping to mitigate environmental impact and bring more low-cost lithium to the market as a whole. GM looks forward to working with CTR, in addition to state and local leaders, in achieving these goals."

GM will be the first company to make a multi-million dollar investment in CTR's Hell's Kitchen project. As the first investor in the project, GM will have first rights on lithium produced by the first stage of the Hell's Kitchen project, including an option for a multi-year relationship, which will be key for GM as lithium demand rises in the auto industry.

The first stage of the Hell's Kitchen project is expected to begin yielding lithium in 2024, which will support GM's plans to build millions of EVs over the next decade.

Eric Walz

Originally hailing from New Jersey, Eric is a automotive & technology reporter covering the high-tech industry here in Silicon Valley. He has over 15 years of automotive experience and a bachelors degree in computer science. These skills, combined with technical writing and news reporting, allows him to fully understand and identify new and innovative technologies in the auto industry and beyond. He has worked at Uber on self-driving cars and as a technical writer, helping people to understand and work with technology.