Massachusetts Institute of Technology (MIT) researchers have developed a low-temperature process to extract battery-grade lithium from spodumene, the most common lithium-bearing hard rock mineral.

The researchers said the method could reduce the cost and waste associated with conventional hard rock lithium extraction.

Even though the U.S., Europe, and Australia have abundant lithium resources within their borders, China dominates the global lithium refining. The biggest hurdle for the U.S. and Australia is extracting lithium from hard rock minerals in a usable form.

The MIT process uses a liquid reagent to dissolve the rock into its constituent parts. It can produce battery-ready lithium salts, smelter-grade alumina, and cement-ready silica. The solvent and reagent can be recovered and reused, bringing waste levels close to zero.

The team first dissolved silica in a mixture of water and ammonium fluoride, reversing the sequence used in conventional chemistry-based extraction methods. The researchers showed they could dissolve spodumene at room temperature.

After dissolving the rock, the team isolated lithium fluoride, which is used as an input in common battery electrolytes. It also developed processes to isolate lithium hydroxide and lithium carbonate, two lithium salts used in battery cathodes. Some of the processes involved the addition of carbon dioxide or sodium carbonate.

The researchers also worked on recovering aluminum and silica from the dissolved mineral. The aluminum was isolated using a high-temperature separation technique, while silica was isolated by precipitation. Silica was tested as a cement additive, and the lithium salts were evaluated for battery-grade purity.

The researchers said the circular process depends on the recovery of ammonium fluoride. According to Yet-Ming Chiang, MIT’s Kyocera Professor of Materials Science and Engineering, ammonia gas is released during the process and can be reapplied to precipitate silica, thereby regenerating the starting ammonium fluoride.

Conventional hard rock lithium extraction requires heating the rock to more than 1,000 degrees Celsius and chemically leaching it to recover lithium, with the remaining rock discarded. Researchers said the new process could make hard-rock lithium extraction cost-competitive with brine extraction, which also has environmental drawbacks.

The team processed 17 spodumene rock samples, demonstrating the method’s applicability across different locations.

Conventional chemistry-based methods for extracting metals from ores preferentially dissolve more reactive elements and leave behind a silica-enriched residue because of the strength of silicon-oxygen bonds. By designing their process to use a mixture of water and ammonium fluoride, the researchers can first dissolve silica, then reverse the process.

According to an International Energy Agency report, the global lithium-ion battery market exceeded $150 billion in 2025, up 20% from 2024.

In another study on alternatives to lithium-ion batteries, research found that sodium-ion batteries could charge faster than lithium-ion batteries, according to an experimental study led by the Department of Applied Chemistry at Tokyo University of Science.