Flux XII has announced it has raised $3.95 million in seed funding to advance the development and deployment of its aqueous flow battery technology. The funding round, led by the Grantham Foundation for the Protection of the Environment, also saw participation from the Wisconsin Alumni Research Foundation, Desai Ventures, and Gener8tor. Flux XII claims that its approach, which focuses on materials integration for grid-scale energy storage, has garnered backing from Activate Fellowship, Third Derivative, Gigascale Capital, the Collaborative Fund, Safar Partners, and LiquidMetal Ventures.
With the new funding, Flux XII says it has scaled up production of both electrolyte and membrane materials using industrial processes and has begun testing multiple kilowatt-scale prototypes. The company plans to validate its minimal viable product (MVP) battery module under controlled conditions in 2026, followed by the design of a fully integrated, containerized battery energy storage system (BESS). In addition, Flux XII is building a consortium of utilities, developers, universities, and research organizations to support pilot system testing in 2027.
Flux XII’s technology uses high-performance, tunable flow battery materials derived from abundant chemical feedstocks. The company states that this approach reduces both cost and system footprint, while maintaining high efficiency and stability. Flux XII produces its electrolytes and membranes via industrial processes, integrating them into battery systems designed for megawatt-scale deployment by commercial suppliers. It aims to reduce the capital expenditure of flow battery systems by 50 percent at the 100 megawatt scale, unlocking cost-effective energy storage for markets including data centers, electric vehicle infrastructure, onshoring manufacturing, and grid electrification.
“Grid power developers need more capacity, and it needs to be cheaper, safer, and cleaner than gas or lithium-ion batteries,” said Dr. Patrick Sullivan, co-founder and CEO of Flux XII. “Flux is developing a comprehensive product that builds off decades of industry advancements and addresses these key points without the tradeoffs of competing energy storage solutions.”
Josh Agenbroad of the Grantham Foundation stated, “We’ve reviewed many new technologies, but Flux XII is a standout with the potential for greatly reducing the cost of energy storage,” adding, “The chemistry is safe and rapidly scalable. This is what’s needed for renewables to undercut thermal generation, even overnight or when the wind isn’t blowing.”
Source: Flux XII
