CMBlu Energy, a German deep-tech company and sole inventor of the SolidFlow non-lithium long-duration battery, has crossed the €1 billion valuation threshold following a €50 million initial close of its Series C financing with participation from Samsung Ventures. All existing investors, including STRABAG SE, also joined the round. The milestone reflects accelerating commercial validation as data centers and utilities seek dependable, multi-hour energy solutions at scale.
Founded in 2014 and headquartered in Alzenau, Germany, CMBlu evolved from one of Europe’s largest lithium-free battery research laboratories into a rapidly scaling energy storage innovator with more than 250 employees, including over 150 scientists and engineers. The company is scaling manufacturing through its automated gigafactory in Alzenau, with additional facilities planned in the United States and Greece to support resilient, localized supply chains.
CMBlu’s SolidFlow technology represents a fundamental departure from lithium-dominated storage, introducing a long-duration architecture purpose-built for multi-gigawatt-hour deployment. The system combines non-flammable, water-based electrolytes with proprietary solid energy storage materials, decoupling power from energy capacity to enable cost-effective scaling. Built from earth-abundant, recyclable materials, SolidFlow avoids foreign-entity-of-concern supply chains for U.S. customers while supporting long-life, infrastructure-grade performance. The system is engineered to deliver ten hours or more of dispatchable energy, addressing one of the most pressing structural constraints on hyperscale growth: how to secure dependable, multi-hour capacity as electricity demand outpaces grid expansion.
As proof of commercial momentum, CMBlu has secured a 5 GWh framework agreement with Uniper, one of Europe’s leading utilities. That volume is equivalent to powering a 1 GW data center for five hours or supplying a 500 MW data center for ten continuous hours, covering the full overnight window when solar generation drops to zero. By shifting excess daytime generation into peak and overnight demand periods, SolidFlow enables data centers to operate on some of the lowest-cost electricity available while maintaining uptime and grid stability.
The initial Series C close will support manufacturing scale-up and accelerate early commercial deployments in Europe and the United States.
KEY QUOTES:
“Our SolidFlow technology is redefining energy storage by combining inherent safety with a streamlined permitting pathway, enabling faster, more predictable deployment at scale. That speed to power paired with resilient, localized supply chains is critical as data centers and industrial customers advance their business needs and race to meet surging demand. Customers powering critical operations need energy they can count on through the night and under real-world conditions while maximizing efficiency. CMBlu’s innovative battery tech makes this possible and the market is rewarding technologies that can deliver superior performance and dependability.”
Constantin Eis, CEO, CMBlu Energy
“CMBlu’s innovative solution stands out as an industry leading approach to scaling sustainable, long-duration energy storage solutions and positions the company as a key enabler of the global energy transition. This partnership underscores our dedication to supporting technologies that not only accelerate energy innovation but also meet the rising power demands of an AI and electrification driven world.”
Samsung Ventures
