What Sinergy Flow does

Sinergy Flow S.r.l. is an Italy-based DeepTech startup founded in 2022 and headquartered in Milan, with an operational R&D facility in Rho (Milan) comprising over 350 m² of laboratories and in-house cell prototyping capacity. The company is developing a proprietary sulfur-based redox flow battery for long-duration stationary energy storage, exploiting sulfur — a low-cost byproduct of the petrochemical industry — together with other earth-abundant materials. The modular and scalable architecture is designed with a customizable energy-to-power ratio for continuous operation exceeding 10 hours, targeting multi-day storage use cases intended to enable renewable energy penetration up to 90% on the grid.

The company's core product is a single redox flow battery platform serving European grid operators, multi-utility companies, and utility-scale energy storage customers. Sinergy Flow pursues a direct enterprise sales model focused on proof-of-concept collaborations (notably with Italian multi-utility A2A) as the bridge from pilot validation to industrial deployment. Pricing is not publicly disclosed and is expected to be quote-based for utility-scale B2B engagements. Revenue mechanics at this stage are anchored on hardware system sales and associated commissioning, with no commercial-scale deployments reported and no disclosed revenue, ARR, or shipments.

Sinergy Flow has raised approximately €8.8 million across two funding rounds: a €1.8 million seed round in November 2022 led by 360 Capital (Poli 360) and A+360 with Tech4Planet participation, and a €7 million late-seed round in February 2026 led by CDP Venture Capital SGR with 360 Capital, Tech4Planet, and new investor Exergon. The company originated from doctoral research at Politecnico di Milano by founders Alessandra Accogli (CEO), Gabriele Panzeri (CTO), and Matteo Salerno (COO/CSO), and has been recognized through the Everis Awards 2021, Startcup Lombardia 2021, Premio Nazionale Innovazione 2021, Intellectual Property Awards 2021, and ENI Awards 2022. According to the company, the technology has been scaled more than 10,000x since inception, and a dedicated 12-person team now spans R&D management, battery science, electrochemistry, cell engineering, mechanical design, and development engineering.

Name

Sinergy Flow

Legal name

Sinergy Flow S.r.l.

Website

https://sinergyflow.com

Company type

Private

Founded year

2022

Operating status

Operating

Headcount range

1–10 employees

Short description

Sinergy Flow is a Milan-based DeepTech startup developing a sulfur-based redox flow battery for long-duration (10+ hours) stationary energy storage. Founded in 2022, it serves European grid operators and utilities — notably Italian multi-utility A2A — and remains in pre-commercial pilot validation.

Ownership category

akta.pro rank

Product category

Grid-Scale Energy Storage

NAICS

Battery Manufacturing (33591), Electric Power Generation (22111)

SIC

Electronic Coils, Transformers & Other Inductors (3677), Motors & Generators (3621)

akta.pro primary industry

Electrochemical LDES (Flow Batteries & Other Long-Duration Batteries) (EUAFADAA)

akta.pro secondary industry

Battery Repair, Refurbishment & Remanufacturing Services (Module/Pack Repair, Rework) (EUAFACAI)

Keywords

• Redox flow batteries
• Long-duration storage
• Grid-scale energy storage
• Sulfur battery technology
• Stationary energy storage

Headquarters

HQ city

Milano

HQ country

Italy

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Technology or R&D, Infrastructure, Operations, Marketing or Sales

Revenue model

1. Redox Flow Battery Systems: Sinergy Flow generates revenue through the sale of long-duration energy storage systems (flow batteries) to utility-scale customers and grid operators. The company is in the process of scaling from proof-of-concept validation with A2A toward commercial-scale deployment. Revenue is derived from hardware system sales with associated commissioning and potentially service contracts.

Go-to-market motion2 records

Distribution channels1 record

Marketing channels4 records

Core offering

Sinergy Flow develops and sells sulfur-based redox flow battery systems for long-duration stationary energy storage. The hardware is modular and scalable, uses sulfur (a petrochemical industry byproduct) as the active material, and is designed for continuous operation exceeding 10 hours to support renewable integration at grid-scale. Customers are European grid operators and multi-utility companies seeking cost-effective, Circular Economy-compliant storage for renewable-heavy grids.

Product overview

Sinergy Flow offers a single core product: its proprietary low-cost redox flow battery technology for long-duration energy storage. The modular and scalable battery system uses sulfur—a petrochemical industry byproduct—and other earth-abundant materials, making it compliant with Circular Economy principles. The technology is designed for stationary utility-scale storage and grid support applications, with customizable energy-to-power ratios suitable for storage exceeding 10 hours of continuous operation.

Differentiator

Problem solved

Functional benefit

Products and services

• Redox Flow Battery System Sulfur-based redox flow battery hardware for long-duration stationary energy storage exceeding 10 hours of continuous operation. Modular and scalable with customizable energy-to-power ratio, using earth-abundant and Circular Economy-compliant materials to enable renewable energy penetration up to 90%. Sold to European grid operators and multi-utility companies for utility-scale deployments.

Quantifiable outcome

• Technology scaled more than 10,000x since inception
• +3 more outcomes

Named customers1 record

Segments1 record

Ideal customer profiles1 record

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

Three partnerships are on record, tiered core and supporting.

• A2AcoreStrategic or Co-development PartnerSinergy Flow is executing a proof-of-concept collaboration with Italian multi-utility company A2A to validate its redox flow battery technology under real operational conditions ahead of industrial deployment. This is the company's primary customer-facing partnership for technology validation and represents a strategic bridge between the startup and industrial deployment.
• PoliHubsupportingStrategic or Co-development PartnerSinergy Flow is linked to PoliHub, the startup incubator of Politecnico di Milano. The company originated from doctoral research at Politecnico di Milano and participated in the Switch2Product Challenge hosted by the university, where the project was awarded. PoliHub provides incubation support, resources, and network access for the startup's early development.
• Politecnico di MilanosupportingStrategic or Co-development PartnerThe company originated from doctoral research conducted at Politecnico di Milano, where founders Alessandra Accogli (CEO), Gabriele Panzeri (CTO), and Matteo Salerno (COO/CSO) developed the new chemistry for redox flow batteries. The team participated in and won the Switch2Product Challenge at the university, marking the commencement of the startup's journey.

Scale indicators4 records

Recent moves5 records

Expansion highlights5 records

Direct peers

• Invinity Energy Systems: Invinity is a commercial-stage vanadium redox flow battery manufacturer selling modular stationary storage systems to utilities and microgrid customers globally. It is the closest direct competitor to Sinergy Flow in electrochemical long-duration energy storage for utility-scale grid applications.
• VRB Energy: VRB Energy is a leading vanadium redox flow battery developer with utility-scale projects across China, Africa, and North America. It competes directly with Sinergy Flow in the long-duration stationary storage market and shares the same flow battery business model targeting grid operators and multi-utility customers.
• CellCube (Enerox GmbH): CellCube manufactures vanadium redox flow battery systems for commercial, industrial, and utility-scale energy storage. It is a direct peer of Sinergy Flow in the electrochemical long-duration energy storage category, targeting similar European utility and grid-scale customers.
• Redflow Limited: Redflow develops zinc-bromine redox flow batteries for stationary energy storage. It is a direct peer of Sinergy Flow as an electrochemical flow battery company focused on long-duration applications, though it uses a different active chemistry.
• ESS Inc. ESS Inc. manufactures iron flow batteries for long-duration stationary energy storage, targeting utility and commercial customers. It competes directly with Sinergy Flow in the long-duration energy storage segment, differentiated by its iron-based chemistry rather than Sinergy Flow's sulfur-based chemistry.
• Form Energy: Form Energy is developing iron-air batteries for multi-day (100+ hour) stationary energy storage, with utility customers including Great River Energy and Georgia Power. It is a direct peer of Sinergy Flow in the long-duration energy storage market, differentiated by its iron-air chemistry and even longer duration target.

Broad incumbents

• Sumitomo Electric Industries: Sumitomo Electric is a large industrial conglomerate that has commercialized vanadium redox flow battery technology and deployed utility-scale systems, particularly in Japan. It is a broad incumbent in the same long-duration flow battery space as Sinergy Flow, with a much wider product portfolio.

Emerging players

• Highview Power: Highview Power is commercializing liquid air energy storage (LAES) for long-duration grid-scale applications, with operational projects in the UK and US. It is an emerging player in the LDES market adjacent to Sinergy Flow's flow battery offering, competing for the same utility customer budgets but with a different storage modality.
• Energy Vault: Energy Vault develops gravity-based and hybrid energy storage systems for utility-scale long-duration applications. It is an emerging player competing for the same multi-hour to multi-day stationary storage budgets as Sinergy Flow, but using mechanical rather than electrochemical storage.

Others

• A2A: A2A is a major Italian multi-utility company and Sinergy Flow's pilot customer and co-development partner. It is included as a peer because it is both a customer and a strategic anchor in Sinergy Flow's commercialization path, providing a reference relationship rather than competing directly.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• YouTubeyoutube.com/@sinergyflow9105
• LinkedInlinkedin.com/company/sinergyflow

Revenue estimate

Valuation estimate

Number of profiles

Profiles5 records

Funding overview

Funding rounds3 records

Investors6 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Sinergy Flow