XL Batteries is a technology company focused on developing and deploying safe, low-cost, and reliable grid-scale battery storage solutions. Founded in 2019 by scientists from Columbia University, the company is headquartered in Marlborough, Massachusetts. XL Batteries emerged from research that identified a unique organic chemistry with significant potential for grid-scale energy storage. The company aims to facilitate the global transition to renewable energy by providing durable and affordable energy storage systems designed to meet diverse power needs. With a mission centered on carbon neutrality and a commitment to sustainability, XL Batteries is working to establish a global presence in the energy storage market.
XL Batteries employs a team with expertise in chemistry, engineering, industrial operations, and entrepreneurship. This group focuses on aligning technological development with market demands and global sustainability goals. The company has secured approximately $16.22 million in funding to date, including a $10 million Seed-2 round in February 2023. XL Batteries is actively recruiting professionals passionate about sustainable energy to support its expansion and commercialization efforts.
Battery Technology
XL Batteries specializes in Organic Flow Battery technology for long-duration energy storage (LDES) applications at the grid scale. This technology utilizes a patented pH-neutral organic chemistry, employing molecules historically known but newly applied within a battery format. The system operates on flow battery architecture, including fluid storage tanks and a 40-foot shipping container housing proprietary components.
Key technical features include a proprietary organic electrolyte chemistry suspended in water that can accept a high number of electrons. The flow battery architecture is modular and scalable; capacity is scaled by increasing tank size, while power is scaled by adding container units. This allows for flexible deployment across various scales, from industrial to multi-megawatt projects. The technology demonstrates near 100% electrochemical efficiency in controlled settings and is designed for a lifespan exceeding 20 years. The use of organic, nonflammable electrolytes enhances safety and sustainability by avoiding corrosive chemicals and rare metals common in other battery types. The materials used are derived from globally available commodity chemicals, reducing reliance on constrained supply chains for metals like lithium, cobalt, and nickel.
Recent Projects
In April 2025, XL Batteries launched its first grid-scale Organic Flow Battery project. This followed the successful commissioning of their initial organic flow battery pilot project with Stolthaven Terminals on April 8, 2025. This pilot, installed at Stolthaven Terminals’ Houston facility, demonstrated the system’s operational safety, reliability, and cost-effectiveness in a real-world industrial setting. These projects mark significant steps in the company’s transition from research and development to commercial deployment of its technology.
Investors
XL Batteries has received funding from a mix of institutional venture capital firms and individual investors. Catalus Capital led the company’s $10 million Seed-2 round. SIP Global Partners and Xerox Ventures also participated in the Seed-2 round, investing alongside Catalus Capital. Repeat individual investors include Jeffrey Schwarz, Joel Greenblatt, and Robert Goldstein, indicating continued confidence in the company’s technology and market approach.
Business Details
Location: Marlborough, Massachusetts, USA
Website: https://xlbatteries.com/
LinkedIn: https://www.linkedin.com/company/19166975
