Simon M. King, a Rice University sophomore, served as the first author on a recent study of a new process for recycling lithium-ion batteries. Photo courtesy Rice

Rice University researchers have uncovered a more energy-efficient and faster way to recycle critical minerals from used lithium-ion batteries.

Traditional methods rely on high heat, long processing times and harsh chemicals to recover a small fraction of critical materials from batteries used in everything from smartphones to electric vehicles. However, the team from Rice's Department of Materials Science and Nanoengineering developed a process that uses a water-based solution containing amino chlorides to extract more metals in less time

The team published the findings in a recent edition of the scientific journal Small.

Simon King, a sophomore studying chemical and biomolecular engineering who completed this work as a summer research fellow at the Rice Advanced Materials Institute, served as first author of the study. He worked with corresponding authors Pulickel Ajayan, the Benjamin M. and Mary Greenwood Anderson Professor of Engineering, and Sohini Bhattacharyya, a research scientist in Ajayan’s lab.

By using a hydroxylammonium chloride (HACI) solution, the team achieved roughly 65 percent extraction of key battery metals in just one minute at room temperature, according to the study. The efficiencies grew to roughly 75 percent for several metals under longer processing times.

“We were surprised by just how fast the reaction occurs, especially without the involvement of high temperatures,” King said in a news release. “Within the first minute, we’re already seeing the majority of the metal extraction take place.”

By not requiring high temperatures or long reaction times, Rice predicts the process could have a major impact on cost and the environmental impact of lithium battery recycling. Additionally, the water-based HACI solution makes waste handling easier and lowers certain environmental risks.

In addition to extracting the materials, the team went on to demonstrate that the recovered metals could be recycled and reprocessed into new battery materials.

“A big advantage of this system is that it works under relatively mild conditions,” Ajayan added in the release. “That opens the door to more sustainable and scalable recycling technologies.”

The Rice team's process is up to 10 times more effective than existing lithium-ion battery recycling. Photo by Gustavo Raskosky/Rice University

Houston scientists discover breakthrough process for lithium-ion battery recycling

researching for the future

With the rise of electric vehicles, every ounce of lithium in lithium-ion batteries is precious. A team of scientists from Rice University has figured out a way to retrieve as much as 50 percent of the material in used battery cathodes in as little as 30 seconds.

Researchers at Rice University’s Nanomaterials Laboratory led by Department of Materials Science and NanoEngineering Chair Pulickel Ajayan released the findings a new study published in Advanced Functional Materials. Their work shows that the process overcomes a “bottleneck” in lithium-ion battery recycling technology. The researchers described a “rapid, efficient and environmentally friendly method for selective lithium recovery using microwave radiation and a readily biodegradable solvent,” according to a news release.

Past recycling methods have involved harsh acids, and alternative eco-friendly solvents like deep eutectic solvents (DESs) at times have not been as efficient and economically viable. Current recycling methods recover less than 5 percent of lithium, which is due to contamination and loss during the process.

In order to leach other metals like cobalt or nickel, both the choline chloride and the ethylene glycol have to be involved in the process, according to the researchers at Rice. The researchers submerged the battery waste material in the solvent and blasted it with microwave radiation since they knew that of the two substances only choline chloride is good at absorbing microwaves.

Microwave-assisted heating can achieve similar efficiencies like traditional oil bath heating almost 100 times faster. Using the microwave-based process, Rice found that it took 15 minutes to leach 87 percent of the lithium, which differs from the 12 hours needed to obtain the same recovery rate via oil bath heating.

“This method not only enhances the recovery rate but also minimizes environmental impact, which makes it a promising step toward deploying DES-based recycling systems at scale for selective metal recovery,” Ajayan says in the release.

Due to rise in EV production, the lithium-ion battery global market is expected to grow by over 23 percent in the next eight years, and was previously valued at over $65 billion in 2023.

“We’ve seen a colossal growth in LIB use in recent years, which inevitably raises concerns as to the availability of critical metals like lithium, cobalt and nickel that are used in the cathodes,” the study's co-author, Sohini Bhattacharyya, adds. “It’s therefore really important to recycle spent LIBs to recover these metals.”

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Houston startup strikes deal to develop hydrogen production plant in Canada

hydrogen partnership

Houston-based cleantech startup Vema Hydrogen has reached a tentative agreement with Canada-based CHARBONE Corp. to develop a hydrogen production and processing plant in Québec.

The deal would couple Vema’s production of engineered mineral hydrogen with CHARBONE’s purification, compression and distribution capabilities.

Engineered mineral hydrogen, also known as orange hydrogen, is produced underground by accelerating naturally occurring geochemical reactions in iron-rich rock formations, according to the journal Energy & Environmental Science.

“Across high-value markets — from aviation and maritime fuels to industrial gases — there is incredible demand for Vema’s low-carbon [hydrogen]. Now, more than ever, we need a pathway to deliver these low-carbon fuels,” Pierre Levin, CEO of Vema, said in a news release.

The project would enable Vema to expand into emerging markets like low-carbon maritime and aviation fuel, e-fuels and power generation. Incorporating CHARBONE’s capabilities, the agreement would also support Québec’s hydrogen supply chain.

“The market is demanding high-value industrial gases, and our customers need cleaner, more reliable supply. By pairing Vema’s [hydrogen] feedstock with our purification and distribution capabilities, we’re strengthening Québec’s position as a regional hub for next-generation hydrogen,” Dave Gagnon, CEO of CHARBONE, added in the release.

Vema said in February that it had completed drilling of its first two pilot wells in Québec, making them the world’s first pilot well for orange hydrogen. It’s the first time Vema’s technology has been used outside a lab.

“This pilot will provide the critical data needed to validate [our hydrogen] at commercial scale and demonstrate that Quebec can lead the world in this emerging clean energy category,” Levin said. “The quality of the rock within our core samples is exactly what we expected and is very promising for hydrogen yields.”

Shortly before Vema carried out the pilot drilling, it signed a 10-year deal with California-based energy technology company Verne Power to supply clean hydrogen for California data centers. Over the course of the 10-year agreement, Vema will boost annual production of orange hydrogen to more than 36,000 metric tons.

“There is a robust market for baseload power generation across the U.S., where data centers are straining the grid,” Levin said. “As we power California’s fastest-growing markets with clean hydrogen, we look toward expanding our hydrogen to markets globally and supporting AI-driven power hubs.”

Vema, founded two years ago, raised $13 million in seed funding in 2025.

“The energy transition and emerging uses of hydrogen have spurred demand for clean hydrogen,” Levin said in its funding announcement. “However, existing decarbonized hydrogen production methods simply don’t work — they are too costly and energy-intensive. Vema is here to change that. It’s time to unlock a new era of scalable, low-carbon hydrogen.”

Greentown names 5 climatech startups to manufacturing accelerator

Catalyst Cohort

Greentown Labs has named five climatech startups to its Go Make 2026 cohort, including one from Houston.

Greentown Go Make 2026 is in partnership with Shell Catalysts & Technologies and Technip Energies. Startups will be able to collaborate with leadership from Shell and Technip and have opportunities to work directly with their process engineering teams and develop potential partnerships, pilots and demonstrations, according to Greentown.

This year's manufacturing cohort focuses specifically on process technology and catalytic innovations, which, according to Greentown, have the potential to be a "critical enabler of the global energy transition." Greentown shares that 90 percent of chemical processes depend on catalysis, but traditional methods rely on fossil fuels and consume significant amounts of energy.

“Catalysis underpins the majority of industrial chemical processes, which together account for a significant share of global emissions, making it a critical lever for reducing carbon intensity while improving performance,” Georgina Campbell Flatter, CEO of Greentown, said in a news release. “Greentown Go Make 2026 is designed to close the gap between breakthrough innovation and industrial deployment. By connecting startups with Shell and Technip Energies’ technical expertise and global scale, we’re helping accelerate solutions that improve efficiency and drive industrial decarbonization.”

The five Greentown Go Make 2026 companies include:

  • Houston-based Biosimo, which makes scalable biochemicals from ethanol
  • Missouri-based Catalyxx, which transforms bioethanol into drop-in, cost-competitive, carbon-negative chemicals
  • Sydney, Australia-based HydGene Renewables, which produces low-carbon hydrogen and industrial chemicals from waste biomass
  • Switzerland-based TreaTech, which turns waste into renewable gas, water and minerals through catalytic hydrothermal gasification
  • California-based Unifuel, which has developed a chemical technology platform to make sustainable aviation fuel, renewable gasoline and other renewable chemicals

The cohort will be celebrated at a kickoff event in Houston at The Ion on June 9.

In addition to Greentown Go Make, Greentown also runs its Go Move (transportation), Go Energize (energy and electricity), Go Build (buildings), and Go Grow (food and agriculture) cohort-based programs. The climatech incubator announced its Go Build 2026 cohort in March. Read more here.