California awards grant to LLNL and DarmokTech to develop recyclable sodium batteries

Lithium-ion batteries are everywhere: in phones, computers and more. The technology primarily uses liquid electrolytes, which facilitate charge moving from electrode to electrode, but they can also leak, short-circuit the battery and — in some cases — cause fires. In broader applications such as electrical grid storage, lithium scarcity also makes it difficult to rely on lithium batteries for growing energy demands. This is an increasingly important factor in the energy-intensive age of artificial intelligence.

Alternatively, solid, polymer-based electrolytes could provide a more stable and recyclable option. Using sodium instead of lithium would also make the batteries more cost-effective and less dependent on scarce resources. However, thus far, this technology hasn’t been optimized for grid storage applications, which are a high priority for national security and industry needs alike.

To address this critical energy need, the California Energy Commission recently awarded local startup DarmokTech and Lawrence Livermore National Laboratory (LLNL) a grant of $2 million over three years to pursue recyclable, sodium polymer-based batteries. The technology aims to enhance cost-effective energy storage and grid reliability in the state and beyond. The collaboration is indicative of the type of public-private partnerships that develop as a result of technology transfer and the entrepreneurial programs run by LLNL’s Innovation and Partnerships Office (IPO).

DarmokTech, based in Livermore, Calif., will provide a custom battery cell design that aims to enable non-shredding recyclability. Currently, recycling batteries requires an intensive and expensive shredding process to extract and recover the electrodes — making it commercially impractical on a large scale.

“If you can achieve a non-shredding disassembly, where you can get to those electrodes by essentially pulling them apart, it becomes easy for someone to come in and regenerate, reuse, remake batteries,” said LLNL polymer chemist Johanna Schwartz, who is leading the Laboratory’s research effort as principal investigator. “That is what the DarmokTech battery design will do.”

To make that happen, LLNL is developing polymer electrolytes that have high conductivity and the right material properties to enable disassembly.

LLNL’s role in the project is based on using the Laboratory’s Studying-Polymers-On a-Chip (SPOC) technology to mix, deposit and screen polymer and composite electrolyte materials — all in one platform that is available for commercialization and has been filed for a patent.

“Polymers and composites can be very viscous, like hair gel, honey or slime,” said Schwartz. “Normally, someone like me has to go in and mix these viscous materials by hand. Cast it by hand. Test it by hand. Find out it sucks. And then do that whole process all over again.”

Instead, with SPOC, Schwartz and her team can screen potential electrolyte materials quickly — carrying forward only the best options for further screening. The SPOC technology can also measure performance across multiple replicates and observe day-to-day changes in a high throughput way, providing more reliable information to accelerate optimization. In this process, researchers acquire massive amounts of data that can be used to train machine learning algorithms.

“We're trying to move from high throughput screening to autonomous screening of electrolytes,” said Schwartz. “The idea is that SPOC itself could pick formulations for further training without human interference.”

Work under the grant will begin this month. At the end of the project, the team hopes to have a DarmokTech battery with an LLNL electrolyte that meets energy storage requirements and is accessible to manufacture and take to market.  Schwartz and her team have actively worked with LLNL’s IPO to protect related intellectual property and collaborate with industry partners, like DarmokTech, to mature various technology toward the greatest possible impact.

The SPOC technology came about as a result of the Laboratory Directed Research and Development (LDRD) program, which enables LLNL to fund creative fundamental and applied research activities in areas aligned with its missions to enable high-risk, potentially high-payoff, projects at the forefront of science and technology.

The partnership with DarmokTech was made possible through a series of entrepreneurship programs IPO facilitates for LLNL, in which Schwartz participated. The National Lab Accelerator Program in 2022 introduced Schwartz to DarmokTech, and culminated in a pitch competition to Silicon Valley investors in Palo Alto. The partnership will continue with this grant funding and work toward a commercial-ready energy storage solution for grid resilience.

LLNL Business Development Executive Austin Smith is responsible for the Laboratory’s Advanced Manufacturing IP portfolio. IPO is the focal point for LLNL’s engagement with industry. It aims to accelerate U.S. national security and competitiveness by identifying new economic opportunities and solutions and transferring those to the private sector through licensing or partnerships.