XL Batteries is commercializing an organic flow battery that replaces scarce, corrosive vanadium with inexpensive, proprietary organic electrolytes, resulting in safer, non-flammable and lower-cost long-duration energy storage. The technology leverages proven flow-battery architecture while eliminating the need for specialized supply chains, enabling flexible deployment for grid operators, independent power producers, data centers and heavy industry. Recent milestones include a strategic partnership with Prometheus Hyperscale for large-scale data-center installations—the first U.S. flow-battery deployment of its kind—and a commercial-scale pilot with Stolthaven Terminals in Houston. The company follows a capital-light approach aimed at rapid scaling and market readiness. XL Batteries was founded by Columbia University scientists and is headquartered in Marlborough, Massachusetts. The firm positions itself as an LDES leader capable of enhancing grid resilience amid rising demand from electrification and data-center growth. Financially, XL Batteries has just secured $7.5 million in new capital, which will be used to accelerate commercialization and expand operations.

Total raised

$18M

Funding rounds

2

Latest round

Equity

Latest activity

Sep 2025