Sepion Technologies is a California-based materials company specializing in advanced separator and electrolyte solutions for lithium-ion and lithium-metal batteries. Founded in 2015, the company develops innovative materials that enhance battery safety, performance, and cost-effectiveness for electric vehicle applications. Their proprietary technologies focus on improving energy density while reducing mass through specialized separator coatings and non-flammable electrolytes. The company operates from a 25,000-square-foot facility in Alameda, California, where they conduct research, development, and pilot production of their battery components.
Battery Technology
Sepion Technologies’ primary innovation lies in their coated separator technology, which filters ions at the atomic level. This specialized coating allows lithium ions to pass through while blocking harmful transition metals such as nickel, cobalt, manganese, copper, and iron that can damage battery anodes. The technology results in up to 5% greater volumetric energy density and reduces vehicle mass by approximately 10 kg by eliminating the need for dense ceramic coatings used in conventional separators.
Their non-flammable liquid electrolyte represents another significant advancement in battery safety. This solution features a flash point exceeding 70°C and demonstrates a self-extinguishing time 25 times faster than standard commercial electrolytes. The development process utilizes advanced materials science and machine learning to optimize performance while maintaining compatibility with existing manufacturing processes.
The company’s Alameda facility houses state-of-the-art equipment, including a dry room with cell assembly capabilities for both 2Ah and 20Ah cells. Their slot-die coater produces 330 mm wide coated separators, with an annual production capacity of 500,000 m2 of coated separators and 1 MWh of prototype cells.
Recent Projects
In a significant expansion move, Sepion Technologies secured a $17.5 million grant in 2024 to construct a new lithium-ion battery separator manufacturing facility in West Sacramento, California. The facility, scheduled to begin production in 2027, will produce 50 tons of proprietary polymer and 50 million square meters of coated separator annually – sufficient to power 50,000 electric vehicles. This project includes collaborations with local organizations for workforce development and training programs.
The company also achieved UN/DOT 38.3 safety certification for its products, marking an important milestone in its commitment to safety standards and market readiness.
Investors
Sepion Technologies has attracted substantial investment from prominent financial institutions and strategic partners. Fine Structure Ventures led a $16 million Series A funding round in November 2021, with participation from Solvay Ventures and Alumni Ventures. Additional investors include 11.2 Capital, ACVC Partners, Calm Ventures, and Creative Ventures.
The company has also received significant government support through grants from the California Energy Commission and the U.S. Department of Energy, demonstrating public sector confidence in their technology and mission to advance domestic battery production capabilities.
Business Details
Location: Emeryville, California, USA
Website: https://sepiontechnologies.com
LinkedIn: https://www.linkedin.com/company/18491806
