Seattle startup bets on sodium batteries as cheaper, safer alternative to lithium

Seattle startup bets on sodium batteries as cheaper, safer alternative to lithium Lisa Stiffler

Emerald Battery Labs co-founders from left: David Bell, Kjell Schroder and Aric Stocks. (Emerald Photo)

While most battery startups chase lithium, a new Seattle company is betting on an abundant alternative: sodium.

Emerald Battery Labs is developing materials for sodium-ion batteries because the ingredient is readily available in the U.S. and cheaper than the lithium required for more conventional batteries. Sodium-ion batteries also have significantly longer lifespans and are less likely to catch fire than lithium-ion alternatives.

The tradeoff? They’re less energy dense — meaning they don’t hold as much power per unit of weight and volume, so they need to be larger than competing technologies to deliver the same energy output.

But co-founder and Chief Product Officer David Bell said his startup aims to shrink that power gap.

“We want to solve that energy density problem,” he said. “That’s one of the core aspects for Emerald — we want to make the highest performing sodium-ion battery on the market.”

The company is developing an improved “hard carbon” material that’s used in sodium battery anodes. Its next generation solution will tackle a composite anode product, which has been a strategy for advancement in lithium-ion batteries.

Another strength, Bell said, is the sodium-ion batteries can be made using the same manufacturing line that works for lithium-ion batteries. Companies in China and South Korea are already repurposing some of that infrastructure for sodium applications.

Emerald is targeting several growing applications for sodium-ion batteries:

• Grid-scale energy storage, where utilities can pair intermittent power sources like wind and solar with large-scale battery energy storage systems to extend the availability of renewable power.
• Supporting data center operations, such as providing immediate, short-term power when the electrical grid goes down, and longer-term energy storage.
• Consumer products such as power tools, scooters and electric bikes, forklifts and automotive starter batteries.
• Military defense applications.

Emerald incorporated in March and is using University of Washington resources to develop its technology, including CoMotion Labs and the Washington Clean Energy Testbeds. The company is part of a regional battery hub that includes Group14 Technologies, Ecellix, Sila and others.

The startup is bootstrapped and received funding from two universities that helps pay for student employees.

The founders bring deep battery experience:

• Bell led product management and customer programs at Group14, which is manufacturing next generation silicon anode materials and has raised more than $1 billion from investors. He also held research and management roles at battery materials companies including Ionic Materials.
• Kjell Schroder, CEO and chief technologist, holds a doctoral degree from the University of Texas with a research focus on silicon anodes. Schroder led engineering, R&D and testing work at Form Energy, a startup developing iron-air batteries, and at Ionic and EnPower.
• Aric Stocks, chief operating officer, has a materials engineering background and led a team of global business development managers at Group14. He previously served as a senior product manager at T-Mobile.

Battery companies face intimidating headwinds as many U.S. clean energy supports are being unwound by the Trump administration and given the costs associated with large-scale materials manufacturing. Emerald is looking to partner with existing battery manufacturers to help manage those costs.

But the risks are real. Sodium-ion battery startup Natron shuttered in September despite having $25 million worth of orders for its Michigan factory. OneD Battery Sciences, a company producing lithium-ion battery materials in Washington, folded last summer.

Emerald faces competition from Peak Energy, Nanode Battery Technologies and Unigrid — though the companies are pursuing different strategies to improve performance that Bell predicts will be more costly.

He said the Emerald team is focused on the work that’s underway — prepping prototypes for partners in defense and transportation.

“We’re every day getting closer and closer to our [minimum viable product],” he said. “We’re fully heads down on getting to a product that we’re excited to ship the customers.”

https://ift.tt/pciVoqU October 17, 2025 at 03:27PM GeekWire