Milanese startup Sinergy Flow raises €7 million led by CDP Venture Capital to scale its low-cost, sulfur-based flow battery technology for a sustainable grid.
Beyond Lithium: Sinergy Flow Secures €7M to Commercialize Circular Energy Storage
The Achilles’ heel of renewable energy has always been its intermittency. To achieve a 100% green grid, we need Long-Duration Energy Storage (LDES) that is cheap, scalable, and independent of rare earth minerals. Sinergy Flow is answering this call by turning an industrial byproduct into a powerhouse of clean energy.
Founded in 2022 as a spin-off from Politecnico di Milano, Sinergy Flow has secured €7 million in a round led by CDP Venture Capital (via the EnergyTech and Green Transition funds), with participation from 360 Capital, Exergon, and Tech4Planet.
The Technology: The Power of Sulfur
Traditional batteries rely on lithium, cobalt, and nickel—materials with volatile prices and complex supply chains. Sinergy Flow’s proprietary Redox Flow Battery (RFB) technology utilizes sulfur, a widely available industrial byproduct.
- Long Duration: Designed for stationary storage exceeding 8 to 10 hours.
- Circular Economy: By valorizing sulfur-rich byproducts, the technology reduces industrial waste while providing clean energy.
- Scalability: The team has already scaled the device 10,000-fold since its earliest lab prototypes, recently completing a Proof of Concept with Italian utility giant A2A.
From Lab to Utility-Scale: The Fundreef Toolkit
As Sinergy Flow moves into industrialization and commercial deployment, they face the classic “DeepTech hurdle”: moving from a validated prototype to a bankable utility asset. At Fundreef, we provide the tools to help hardware founders navigate this transition:
- DeepTech Valuation Benchmarks: Flow battery technology is a high-cap-ex game. Use our AI Company Valuation tool to benchmark your progress against 2026 energy storage leaders.
- The Tech-Transfer Roadmap: Sinergy Flow is a textbook case of successful technology transfer. Structure your own spin-off journey with our AI Business Plan tool, specifically designed for capital-intensive R&D.
- Pitching the “Hard Tech” Moat: Communicating the chemistry of flow batteries to generalist VCs requires a clear narrative. Use our Pitch Deck Analyzer to ensure your technical edge is the star of your deck.
- Sourcing “Green” Capital: Looking for your own CDP or Exergon? Our Investor Database lets you filter for VCs who specifically back the Green Transition and industrial sustainability.
- Closing the Late Seed: As you move toward Series A, our AI Term Sheet Analysis ensures you protect your founders’ equity while bringing on the heavy hitters of institutional finance.
