A team of engineers at Nanjing University, working with a pair of colleagues from the University of California, Berkeley, has developed a new way to extract lithium from briny water.

In their paper published in the journal Science, the team describes the process they developed and the device they built and how it could be used to extract lithium from various natural sources. Seth Darling, with Argonne National Laboratory in the U.S., has published a Perspective piece in the same journal issue outlining the work done by the team on this new effort.

Lithium is in high demand due to its use in batteries. Unfortunately, its traditional sources, hard rock ores, are expected to decline in the coming years. Because of that, scientists have been looking for other sources like briny water found in the world’s oceans. Prior research has suggested there is more than enough to meet global demand for as long as needed.

The problem is extracting the lithium in a way that does not pollute the environment and is relatively inexpensive to obtain. In this new effort, the research team has developed an approach called solar transpiration-powered lithium extraction and storage (STLES).

The idea behind the new approach involves using sunlight to extract lithium from brine. It calls for creating a device that floats on the brine’s surface. Inside the device is a membrane made of aluminum oxide with embedded nanoparticles.

When the sun shines on the devices, pressure builds up that forces lithium through the membrane, separating the ions from the brine—a silica ceramic frit with tiny holes in it that stores the lithium salts as they are pulled out. The researchers note that because the system operates passively, it is very inexpensive. They also note that it can be used in places besides the ocean, such as the Dead Sea.

The new approach is not the only one being investigated. Another team at the King Abdullah University of Science and Technology has developed a technique that involves using iron-phosphate electrodes and silver/silver halide redox electrodes to pull lithium ions from brine solution, which is then released into a freshwater compartment. They have also published a paper describing their technique in the journal Science.

More information: Yan Song et al, Solar transpiration–powered lithium extraction and storage, Science (2024). DOI: 10.1126/science.adm7034

Seth B. Darling, The brine of the times, Science (2024). DOI: 10.1126/science.ads3699

Zhen Li et al, Lithium extraction from brine through a decoupled and membrane-free electrochemical cell design, Science (2024). DOI: 10.1126/science.adg8487

Journal information: Science

© 2024 Science X Network

Vehicle electrification is an important pathway to reducing global greenhouse gas emissions. The supply chain for electric vehicle battery materials relies heavily on China, a dependency that can leave the US vulnerable to supply chain disruptions and geopolitical shifts. The Inflation Reduction Act (IRA) offers meaningful incentives for building batteries in the US and diversifying the supply chain, but some loopholes exist.

A recent study by researchers in Carnegie Mellon University’s College of Engineering has analyzed how much impact the IRA is likely to have on incentivizing vehicle electrification and reducing supply chain vulnerabilities. Anthony Cheng, Ph.D. student in Engineering and Public Policy (EPP); Erica Fuchs, professor in EPP; and Jeremy Michalek, professor in EPP and mechanical engineering and director of Carnegie Mellon’s Vehicle Electrification Group, contributed to this research.

The findings are published in the journal Nature Energy.

The total credits offered through the IRA would enable a manufacturer to receive more in tax credits than the total cost of battery production, but qualifying for the full range of credits would be difficult, Michalek explained.

In particular, the 30D New Clean Vehicle Credit, which offers $7,500, can only be claimed on vehicles for which US-designated “Foreign Entities of Concern”—including China, Russia, Iran, and North Korea—played no role in the supply chain, Michalek said.

In a related study earlier this year, EPP researchers analyzed the extent to which electric vehicle supply chains are vulnerable to disruptions, with a focus on China. That study found that for virtually all chemistries, the entire supply chain would be profoundly affected if China’s exports were disrupted.

At the same time, another recent study by EPP researchers found that electric vehicle manufacturing stimulates the job market, as these vehicles require more jobs per vehicle produced than their conventional counterparts.

The new 30D credit offers a major incentive for automakers in the US and allied countries to focus on their own production means and find ways to develop alternatives to Chinese materials in the supply chain, Michalek explained.

However, a major loophole exists in that the restriction on Chinese-origin materials only applies to vehicles sold. An automaker can avoid the restriction by leasing vehicles and instead claiming the 45W Commercial Clean Vehicle Credit, which is currently worth the same amount as the 30D credit.

A supply chain’s flexibility for diversification does not always line up with its credit eligibility. Notably, lithium iron phosphate batteries have more potential to reduce supply chain vulnerabilities and qualify for incentives, but they have smaller total available incentives than nickel- and cobalt-based batteries.

The study found that the IRA primarily incentivizes downstream battery manufacturing diversification, whereas the impact on upstream supply will depend on how automakers respond to Foreign Entities of Concern and leasing rules.

If enough automakers successfully pivot toward a more lease-heavy business model to skirt the restrictions, the policy may need to evolve in order to remain effective, Michalek said, noting that researchers at Carnegie Mellon will continue to monitor the impact and outcome.

More information: Anthony L. Cheng et al, US industrial policy may reduce electric vehicle battery supply chain vulnerabilities and influence technology choice, Nature Energy (2024). DOI: 10.1038/s41560-024-01649-w

Journal information: Nature Energy

The world is rapidly transitioning to renewable power, but there are shortcomings. Solar power falls at night, and wind power recedes and ascends irregularly. New technologies need to be developed that can store energy from the electrical grid when there’s a surplus and deploy it when there’s not enough.

Rechargeable lithium-ion batteries play a crucial role in everyday life, powering devices from smartphones to electric vehicles. However, they rely on limited resources like lithium, nickel, and cobalt, raising concerns about sustainability and cost.

Xiaowei Teng, the James H. Manning Professor in Chemical Engineering at WPI, is leading a team to explore new battery technologies for grid energy storage. The team’s recent results, published in ChemSusChem, suggest that iron, when treated with the electrolyte additive silicate, could create a high-performance alkaline battery anode. The second most abundant metal in the Earth’s crust after aluminum, iron is far more sustainable than nickel and cobalt. The United States alone recycles approximately over 40 million metric tons of iron and steel from scrap each year.

Teng notes that iron is already used as an alkaline battery anode in iron-nickel alkaline batteries—invented by Thomas Edison in the 1900s—but it has low energy efficiency and storage capacity due to the formation of hydrogen gas during charging and inert iron oxide during discharging.

“You don’t want hydrogen gas formation when charging a battery,” said Teng. “It impairs the energy efficiency of the battery system considerably. Without addressing these technical challenges, iron alkaline batteries are less attractive for modern energy storage systems to be coupled with electric grids.”

In the Oct. 7 cover story featured in ChemSusChem, the team reported that adding silicate to the electrolytes allowed them to charge a battery without producing hydrogen.

A chemical compound of silicon and oxygen, silicate has long been used as an inexpensive and simple agent in glass, cement, insulation, and detergents, said Sathya Jagadeesan, a Ph.D. student at WPI and lead author on the paper. The team discovered that silicate also strongly interacts with battery electrodes and suppresses hydrogen gas generation.

Teng said this new process could improve the alkaline iron redox chemistries in iron-air and iron-nickel batteries for energy storage applications, such as microgrids or individual solar or wind farms.

More information: Sathya Narayanan Jagadeesan et al, Unlocking High Capacity and Reversible Alkaline Iron Redox Using Silicate‐Sodium Hydroxide Hybrid Electrolytes, ChemSusChem (2024). DOI: 10.1002/cssc.202400050

Provided by Worcester Polytechnic Institute