For America to move fully away from fossil fuels and to a more sustainable energy economy, batteries are the key ingredient. For both electric vehicles and the power grid, new battery technologies will transform the energy equation behind how we live and how we move.
As part of this effort, the Joint Center for Energy Storage Research (JCESR), an energy innovation hub located at the U.S. Department of Energy’s Argonne National Laboratory, has taken up the battery cause for over 10 years. The research at JCESR has produced breakthroughs that have found their way into electric vehicles as well as lead the creation of several spinoff companies.
One of these companies, Sepion Technologies, has formed to make real the promise of an innovative battery chemistry. The heart of Sepion’s technology is a battery membrane, which separates the two electrodes of a battery. These membranes are especially useful for energy-dense lithium-metal batteries.
Sepion recently secured Series A funding — its first significant round of outside venture capital investment. With the additional capital, Sepion will expand its staff from 10 to 30 people and open a new pilot facility.
“When I was a part of JCESR, we were all thinking about what the future of batteries could possibly look like, and now I’m excited to be a part of it by making real the promise of lab technology in industry,” said Sepion co-founder Peter Frischmann.
“We’ve always had as our mantra that we want to be able to understand electric battery phenomena at the atomic and molecular level so that we can purpose-design batteries for a specific application,” added JCESR Director George Crabtree. “Now companies are coming out of JCESR to fulfill that mission.”
Membranes are crucially important for batteries because they selectively allow charge-carrying ions to move from one side of the battery to the other. Membranes allow a wide variety of batteries to work, from lithium-ion batteries for electric cars to large flow batteries that can be used to store energy on the grid.
“Membranes have always been viewed as a key component to enable next-generation batteries,” Frischmann said. “Our membrane research has evolved as we sought to discover which batteries would have the most transformative impact.”
Frischmann’s journey in battery research began as a postdoctoral researcher working as a JCESR team member at DOE’s Lawrence Berkeley National Laboratory. From the beginning, Frischmann sought ways to develop new battery technologies for maximum impact.
Frischmann gained entry to the National Science Foundation’s I-Corps program, in which he learned the skills needed to become a successful entrepreneur and paved the way for Sepion. “JCESR was the launching point for our technology as well as other battery technologies that are advancing toward commercial success,” Frischmann said.
“Start-ups play a special role — they have a pressing existential concern from the get-go,” Crabtree added. “They operate in a very different way from big companies — they’re always looking for the next opportunity which means they have to be more aggressive, creative, and out there.”
In the I-Corps program, Frischmann realized that his initial game plan — creating membranes for lithium-sulfur batteries — was an overwhelming challenge for a startup. It necessitated a more comprehensive battery overhaul that would have required a long-term commitment as well as large amounts of capital. “When we were looking at lithium-sulfur batteries, we needed to change the whole battery system, including both electrodes of the battery,” Frischmann said. “By focusing on lithium-metal batteries instead, we can keep the cathodes the same as in well-validated lithium-ion batteries, and focus our attention entirely at the anode.” A battery has two electrodes, a positively charged cathode and negatively charged anode, between which lithium ions shuttle.
Lithium-metal batteries use anodes formed of pure lithium metal. They offer a greater amount of energy for every pound than their lithium-ion relatives, making them an attractive option for extending range for applications like electric vehicles and aircraft. “Improving battery performance while lowering cost is imperative to accelerate the transition to sustainable transportation,” Frischmann said.
The principal drawback of lithium-metal batteries lies in their relative instability. As the battery charges and discharges, long needles of lithium tend to form on the anode surface and stretch towards the cathode. If these one-dimensional needles, called lithium dendrites, become too long, they can impair battery performance or even short a battery out.
The key to improving the performance, safety and reliability of lithium-metal batteries, Frischmann realized, lay in making the lithium metal deposits grow in a different way. By using the nanoporous membrane he had created as part of JCESR near the anode surface, he and the Sepion team were able to flatten the previously branching dendrite needles. “Instead of a spike, we were able to create a pancake, which is much better for battery performance,” he said.
With these new membranes and a focus on electrified mobility applications, Sepion gained entry to Cyclotron Road, a Lawrence Berkeley-based incubator. Cyclotron Road seeks to move lab research to the marketplace through startups. This two-year intensive program provided Frischmann with one of the most formative experiences of his career. “Cyclotron Road really taught me to think differently about how I talk about science and how I think about batteries,” he said.
Cyclotron Road is part of the Lab-Embedded Entrepreneurship Program funded through the Department of Energy’s (DOE) Advanced Manufacturing Office (AMO) in the Office of Energy Efficiency and Renewable Energy (EERE).
JCESR is funded by DOE’s Office of Basic Energy Sciences.
The Joint Center for Energy Storage Research (JCESR), a DOE Energy Innovation Hub, is a major partnership that integrates researchers from many disciplines to overcome critical scientific and technical barriers and create new breakthrough energy storage technology. Led by the U.S. Department of Energy’s Argonne National Laboratory, partners include national leaders in science and engineering from academia, the private sector, and national laboratories. Their combined expertise spans the full range of the technology-development pipeline from basic research to prototype development to product engineering to market delivery.
Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.
The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.