Consortium to make batteries for electric vehicles more sustainable

A consortium of battery scientists, led by Lawrence Berkeley National Laboratory (Berkeley Lab), will accelerate the commercialisation of a new family of battery cathode materials called DRX or “disordered rock salt”.

DRX cathodes could provide batteries with higher energy density than conventional lithium-ion battery cathodes made of nickel and cobalt, two metals that are in critically short supply.

The U.S. Department of Energy (DOE) has made it a priority to find ways to reduce or eliminate the use of cobalt in batteries. In support of that initiative, the DRX Consortium is focused on making DRX cathodes made of manganese or titanium, which are both more abundant and cheaper than nickel or cobalt. Lithium batteries made with DRX cathodes could safeguard the automobile industry and therefore consumers from higher prices spurred by supply constraints.

“DRX cathodes can be made with almost any transition metal instead of nickel and cobalt. That versatility is key if we want to replace gasoline vehicles with electric vehicles,” said principal investigator Gerbrand Ceder. He is co-leading the DRX Consortium with fellow battery scientist Guoying Chen at Berkeley Lab.

The DRX Consortium — which includes a team of approximately 50 scientists from Berkeley Lab, SLAC National Accelerator Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, Oak Ridge National Laboratory, and the University of California at Santa Barbara — was awarded $20 million from the Vehicle Technologies Office in DOE’s Office of Energy Efficiency and Renewable Energy. The funding — allocated in $5 million yearly increments through 2025 — will allow the consortium to develop DRX battery cathodes that could perform just as well if not better than the NMC (nickel-manganese-cobalt) cathodes used in today’s lithium-ion batteries.

“DRX offers more sustainable, more abundant, and cheaper mineral sources for battery cathodes,” Ceder said. “The lithium-ion battery is a really good energy storage technology, but to stay relevant, it will need to grow toward higher production of multiple terawatt hours per year. Without DRX, lithium-ion batteries would require enormous amounts of nickel and cobalt if we stay with current technologies.”

“DRX could be the go-to material for battery cathodes,” Chen added. “We already have the advantage of cost and resources. Now all we have to do is improve performance.”

Video credit: Marilyn Sargent/Berkeley Lab.

Decarbonising transportation with DRX

DRX is still a very young technology — Ceder and his team developed DRX in 2014, as a response to a rapidly growing lithium-ion battery industry. New battery technologies typically take 20 to 30 years to mature. But DRX is on an unusually fast track towards commercialisation.

Ceder and Chen demonstrated DRX’s potential during a four-year program called the “Deep Dive”, which was also funded by the DOE Vehicle Technologies Office. That program ended in 2022, and the consortium formed soon after with the goal of demonstrating commercial-ready DRX cathodes in less than five years.

Image caption: Berkeley Lab battery scientists Gerbrand Ceder (left) and Guoying Chen are co-leading the DRX Consortium. Image credit: Marilyn Sargent/Berkeley Lab.

This urgency comes in the midst of a clean energy transition. The United States aims to make half of all new cars sold in 2030 zero-emissions vehicles, including battery electric, plug-in hybrid electric or fuel cell electric vehicles. In California, all new cars must be zero-emission vehicles beginning in 2035.

To achieve this ambitious goal, Ceder and Chen formed the DRX Consortium, enlisting battery scientists from across the country and national lab system to help.

Researchers at the Department of Energy’s National Energy Research Scientific Computing Center (NERSC) will help the team narrow down the best combination of manganese and titanium through computer modelling. Researchers from Oak Ridge National Laboratory and Argonne National Laboratory will work on chemical synthesis and scale up the materials for industry. New DRX-compatible electrolytes will be developed at Pacific Northwest National Laboratory. Researchers from Berkeley Lab’s Molecular Foundry, SLAC National Accelerator Laboratory, and UC Santa Barbara will assist with materials characterisation.

A pioneer in computational materials discovery, Ceder and his team discovered DRX through computer model experiments, many of which were performed at NERSC.

Vince Battaglia and his team at Berkeley Lab will test out Ceder’s DRX cathode “recipes” by fabricating dozens of DRX coin-cell batteries with various formulations of titanium or manganese. The idea is to improve the material’s electronic conductivity, which is crucial to ensuring that a DRX lithium-ion battery not only has high energy density but also a high cycle life (the number of times a battery can charge and discharge before it begins to break down).

“In my lab we can test hundreds of lithium-ion coin cells at a time. We try to make batteries in the best environments possible so that we can really understand the performance of the material itself. It’s scaled up to mimic the fabrication processes that would actually work in the field,” Battaglia said.

This latest chapter in the development of DRX comes at a pivotal moment as nations around the world search for actionable solutions to prevent global warming from worsening. Climate scientists say that replacing gasoline-powered vehicles with electric vehicles could be one of the most effective ways to rapidly decarbonise the transportation sector.

Ceder said that DRX could play a key part in decarbonising transportation. “DRX is a very promising technology that could provide reliable yet inexpensive and abundant energy storage. But this has to happen soon — not in 30 years, but now. We don’t have time to wait — and the DRX Consortium will help us get there,” he said.

This article was originally published by Berkeley Lab.

Top image caption: Jingyang Wang holds up a ceramic palette sample in the battery lab in B33. Image credit: Marilyn Sargent/Berkeley Lab.