Depend on your smart phone? Enjoy a flat screen tv? How about an electric vehicle, do you drive one? These technologies—and other clean energy, information, and defense applications— all rely on rare-earth elements that could be mined in most parts of the world but are primarily processed and refined only in a limited number of countries, like China.

“Right now, the U.S. doesn’t have enough supply to fulfill the objective of the steady clean energy transition, ensure national security, and achieve long-term economic goals” said Gorakh Pawar, a staff scientist at the Idaho National Laboratory who is a visiting scholar at the Center for International Security and Cooperation.  The importance of rare earths mining is highlighted in the series of reports recently issued by the U.S.  Department of Energy in response to President Biden’s Executive Order "America's Supply Chains" signed in 2021.

“This means that the U.S. depends on other countries and therefore, the U.S. needs a strategic approach to resolve the major rare earth elements supply chain issues urgently,” Pawar added. 

Mountain Pass Rare Earth Mine and Processing Facility, Mountain Pass, San Bernardino Co., California (Image credit: MP materials.com)

Rare-earth elements “are moderately abundant in the earth’s crust, but they need to be concentrated to be economically viable,” said Sulgiye Park, a Fellow at CISAC. “What we want is concentrated rare-earth reserves because we are going to spend a lot of money mining and processing it.”

Important deposits of rare earths exist in the U.S. and previously the U.S. was self-reliant in domestically produced rare-earth elements, but mining operations have declined over the last several decades, allowing China to command roughly 90 percent of the global market. Now, however, there are signs that domestic production is making a comeback, and CISAC scholars are both studying and providing support to accelerate this resurgence.

Pawar, Park and CISAC co-director Rod Ewing toured the Mountain Pass Rare Earth Mine and Processing Facility in southern California to learn more about its operation and to determine how their research could help support this important industry.

“We were provided with critical insights into MP Materials' strategy for securing the domestic rare earth supply chain that would significantly reduce U.S. economic dependence on foreign REE,” Ewing said.

“The substantial challenges include developing domestic supply chains for mill equipment and capacity to process rare earths, such as neodymium-praseodymium magnets,” Ewing added.

Pawar, Park and Ewing toured the mine for three hours to see the facilities, ask and answer questions. They wanted to understand the facts on the ground, supply chain issues and industry challenges in a more complete way to enhance their own research.

Open pit mine (Sulphide Queen deposit) at Mountain Pass. The open pit is ~600 m wide. A massive carbonatite forms the core of Mountain Pass that hosts REE mineral resources, including bastnäsite. (Image credit: Gorakh Pawar)

Before the trip, Pawar and Park relied on academic literature, open source information, news stories and press releases about rare-earth elements, like this recent White House release titled “Securing a Made in America Supply Chain for Critical Minerals,” which announced a Department of Defense grant to MP Materials, who operate the Mountain Pass mine.

“Open source is great,” Park said. “But if you have a chance to visit the site, you can learn from the people on the ground who provide a whole new perspective. “

The tour also fortified connections so that the Pawar, Park and Ewing could share their own knowledge and policy-relevant research, as well as their network of colleagues who have different areas of expertise.

CISAC was created in 1983 with the goal of bringing together experts in science and technology with experts in policy. The mission statement has always been “to generate new knowledge for a better world.” And this trip to Southern California was another opportunity to fulfill this mission.

About Idaho National Laboratory
Battelle Energy Alliance manages INL for the U.S. Department of Energy’s Office of Nuclear Energy. INL is the nation’s center for nuclear energy research and development, and also performs research in each of DOE’s strategic goal areas: energy, national security, science and the environment.

Abstract

Unregulated lithium (Li) growth is the major cause of low Coulombic efficiency, short cycle life and safety hazards for rechargeable Li metal batteries. Strategies that aim to achieve large granular Li deposits have been extensively explored, and yet it remains a challenge to achieve the ideal Li deposits, which consist of large Li particles that are seamlessly packed on the electrode and can be reversibly deposited and stripped. Here we report a dense Li deposition (99.49% electrode density) with an ideal columnar structure that is achieved by controlling the uniaxial stack pressure during battery operation. Using multiscale characterization and simulation, we elucidate the critical role of stack pressure on Li nucleation, growth and dissolution processes and propose a Li-reservoir-testing protocol to maintain the ideal Li morphology during extended cycling. The precise manipulation of Li deposition and dissolution is a critical step to enable fast charging and a low-temperature operation for Li metal batteries.

Read the rest at  Nature Energy