ESS Acquires VoltStorage GmbH Intellectual Property and Assets to Advance Flexible Long-Duration Energy Storage
ESS Tech acquires VoltStorage’s iron-salt battery patents and assets to strengthen long-duration energy storage capabilities, aiming to improve grid reliability and reduce costs for utilities and renewable developers.
ESS Tech, Inc. announced on February 18, 2026, the acquisition of VoltStorage GmbH’s intellectual property and assets, including patents and technical expertise in iron-salt battery technology. The deal expands ESS’s existing portfolio, adding VoltStorage’s decade-long research and development in durable, low-cost energy storage systems. The combined technologies are intended to enhance grid stability by enabling extended energy discharge periods, supporting intermittent renewable sources like wind and solar.
The acquisition brings VoltStorage’s team of electrochemistry and materials science specialists into ESS, reinforcing its workforce to advance long-duration storage solutions. ESS, a manufacturer of iron flow batteries since 2011, uses iron, salt, and water in its systems, avoiding scarce materials while maintaining performance. The integration aims to deliver a more flexible and cost-effective storage platform for utilities, renewable developers, and industrial customers.
Drew Buckley, ESS CEO, stated the acquisition aligns with the company’s goal of providing clean, reliable, and affordable energy storage globally. He highlighted the combined expertise in iron flow batteries as a step toward creating an advanced platform for long-duration storage, addressing the growing need for resilient energy infrastructure.
ESS (NYSE: GWH) designs iron flow batteries designed for long-duration use, supporting grid reliability and maximizing the value of excess renewable energy. The company’s technology targets utilities and industrial clients seeking to manage energy demand without disruptions while reducing reliance on fossil fuels.