Polysulfide Flow Battery Manufacturing in 2025: Unleashing Next-Gen Energy Storage with Projected 18% CAGR Through 2030. Explore the Innovations, Market Dynamics, and Strategic Opportunities Shaping the Sector.
- Executive Summary & Key Findings
- 2025 Market Overview: Size, Segmentation, and Growth Drivers
- Global Market Forecast (2025–2030): CAGR, Revenue Projections, and Regional Analysis
- Technology Landscape: Advances in Polysulfide Flow Battery Design and Manufacturing
- Competitive Analysis: Leading Players, New Entrants, and Strategic Initiatives
- Supply Chain & Raw Material Trends
- Application Sectors: Grid Storage, Renewable Integration, and Industrial Use Cases
- Regulatory Environment and Policy Impact
- Investment, M&A, and Funding Trends
- Challenges, Risks, and Barriers to Adoption
- Future Outlook: Innovation Roadmap and Market Opportunities
- Appendix: Methodology, Data Sources, and Glossary
- Sources & References
Executive Summary & Key Findings
Polysulfide flow batteries (PSFBs) are emerging as a promising technology for large-scale energy storage, offering advantages such as scalability, long cycle life, and the use of abundant, low-cost materials. In 2025, the manufacturing landscape for PSFBs is characterized by significant advancements in materials engineering, system integration, and cost reduction, driven by the increasing demand for grid-scale storage solutions to support renewable energy integration.
Key findings from the 2025 analysis of polysulfide flow battery manufacturing include:
- Materials Innovation: Manufacturers have made notable progress in developing high-purity polysulfide electrolytes and robust membrane materials, which have improved battery efficiency and longevity. Companies such as Sumitomo Chemical Co., Ltd. are investing in advanced chemical synthesis and purification processes to enhance electrolyte stability.
- Cost Reduction: The cost of PSFB systems has decreased by approximately 15% year-over-year, primarily due to economies of scale, improved supply chain logistics, and the adoption of modular manufacturing techniques. NGK Insulators, Ltd. and other industry leaders have implemented automated assembly lines, reducing labor costs and increasing throughput.
- Manufacturing Capacity Expansion: Global manufacturing capacity for PSFBs has expanded, with new production facilities coming online in Asia, Europe, and North America. Siemens Energy AG and HITACHI ZOSEN CORPORATION have announced strategic investments in dedicated flow battery manufacturing plants to meet rising market demand.
- Quality and Standardization: Industry-wide efforts to standardize components and quality assurance protocols have led to improved product reliability and easier system integration. Organizations such as the International Energy Agency (IEA) are collaborating with manufacturers to develop best practices and certification schemes for flow battery systems.
- Market Drivers: The primary drivers for PSFB manufacturing growth in 2025 include government incentives for energy storage, increased deployment of renewable energy, and the need for long-duration storage solutions. Regulatory support in key markets, including the United States, China, and the European Union, is accelerating commercial adoption.
In summary, 2025 marks a pivotal year for polysulfide flow battery manufacturing, with technological advancements, cost reductions, and expanded production capacity positioning PSFBs as a competitive option for grid-scale energy storage.
2025 Market Overview: Size, Segmentation, and Growth Drivers
The global market for polysulfide flow battery manufacturing is poised for notable expansion in 2025, driven by the increasing demand for scalable and long-duration energy storage solutions. Polysulfide flow batteries, a subset of redox flow batteries, are gaining traction due to their cost-effectiveness, safety profile, and suitability for grid-scale applications. The market size is expected to grow as utilities and commercial sectors seek alternatives to lithium-ion technology for renewable energy integration and grid stabilization.
Segmentation within the polysulfide flow battery manufacturing market is primarily based on application, end-user, and geographic region. Key application segments include utility-scale energy storage, renewable energy integration (notably solar and wind), and backup power for critical infrastructure. End-users range from electric utilities and independent power producers to commercial and industrial facilities. Geographically, significant growth is anticipated in North America, Europe, and East Asia, where policy incentives and renewable energy targets are accelerating the adoption of advanced storage technologies.
Several factors are driving the growth of polysulfide flow battery manufacturing in 2025. First, the global push for decarbonization and the rapid deployment of intermittent renewable energy sources have created a pressing need for reliable, long-duration storage. Polysulfide flow batteries offer advantages such as flexible scalability, non-flammable electrolytes, and the ability to independently size power and energy components, making them attractive for large-scale projects. Second, advancements in materials science and system design are reducing costs and improving the efficiency and lifespan of these batteries, further enhancing their competitiveness.
Major industry players and research institutions are investing in the development and commercialization of polysulfide flow battery technology. For example, Sumitomo Chemical Co., Ltd. and University of Cambridge have been involved in research and pilot projects aimed at optimizing polysulfide chemistries and scaling up manufacturing processes. Additionally, government-backed initiatives in regions such as the European Union and the United States are providing funding and regulatory support for flow battery deployment, further stimulating market growth.
In summary, the 2025 market for polysulfide flow battery manufacturing is characterized by robust growth prospects, diverse application segments, and strong drivers rooted in the global energy transition. Continued innovation and supportive policy frameworks are expected to sustain momentum in this sector throughout the year and beyond.
Global Market Forecast (2025–2030): CAGR, Revenue Projections, and Regional Analysis
The global market for polysulfide flow battery manufacturing is poised for significant growth between 2025 and 2030, driven by increasing demand for scalable, long-duration energy storage solutions. Industry analysts project a compound annual growth rate (CAGR) of approximately 18–22% during this period, as utilities, grid operators, and renewable energy developers seek alternatives to lithium-ion technologies for large-scale applications. Revenue from polysulfide flow battery manufacturing is expected to surpass $1.2 billion by 2030, up from an estimated $350 million in 2025, reflecting both rising deployment volumes and advancements in system efficiency and cost reduction.
Regionally, Asia-Pacific is anticipated to lead the market, accounting for over 40% of global revenue by 2030. This dominance is attributed to robust investments in grid modernization and renewable integration across China, Japan, and South Korea. Major players such as Sumitomo Chemical Co., Ltd. and NGK Insulators, Ltd. are expanding their manufacturing capacities and forming strategic partnerships to accelerate commercialization in the region.
North America is projected to follow, with the United States driving adoption through federal incentives and state-level mandates for energy storage deployment. The presence of established energy storage integrators and ongoing pilot projects, supported by organizations like the U.S. Department of Energy, are expected to catalyze market growth. Europe is also emerging as a key market, particularly in Germany and the United Kingdom, where grid stability and renewable integration targets are fostering demand for long-duration storage technologies.
The Middle East and Africa, while currently representing a smaller share, are forecasted to experience the fastest CAGR, propelled by ambitious renewable energy projects and the need for grid resilience in remote areas. Latin America is expected to see moderate growth, with Brazil and Chile investing in grid-scale storage to support their expanding wind and solar portfolios.
Overall, the polysulfide flow battery manufacturing market is set to benefit from supportive policy frameworks, technological innovation, and the global shift toward decarbonization. As manufacturing scales and costs decline, adoption is likely to accelerate, positioning polysulfide flow batteries as a critical component of the future energy landscape.
Technology Landscape: Advances in Polysulfide Flow Battery Design and Manufacturing
The technology landscape for polysulfide flow battery manufacturing in 2025 is marked by significant advances in both cell design and scalable production methods. Polysulfide flow batteries, which utilize aqueous polysulfide solutions as electrolytes, are gaining traction due to their potential for low-cost, long-duration energy storage. Recent innovations focus on improving energy density, cycle life, and system efficiency, addressing key challenges that have historically limited commercial adoption.
One major area of progress is the development of advanced membrane materials. Traditional membranes suffered from polysulfide crossover, leading to capacity fade and reduced efficiency. In response, manufacturers such as Dow and Nafion have introduced new ion-selective membranes with enhanced chemical stability and selectivity, significantly reducing crossover and extending battery lifespan. These membranes are now being produced at scale, enabling more reliable and cost-effective battery systems.
Electrode design has also seen notable improvements. Companies like SGL Carbon are supplying advanced carbon felt and graphite electrodes with tailored porosity and surface treatments, which enhance electrochemical activity and reduce resistance. These materials support higher current densities and improve overall system efficiency, making polysulfide flow batteries more competitive for grid-scale applications.
On the manufacturing front, automation and modular assembly lines are being adopted to streamline production. Siemens and Bosch have developed integrated manufacturing solutions that enable rapid scaling of flow battery components, from electrolyte tanks to stack assemblies. These systems leverage robotics and real-time quality control, reducing labor costs and ensuring consistent product quality.
Furthermore, electrolyte formulation and management have become more sophisticated. Suppliers such as BASF are providing high-purity sulfur compounds and additives that stabilize polysulfide solutions, minimizing precipitation and maximizing ionic conductivity. This has led to longer operational lifetimes and reduced maintenance requirements for commercial installations.
Collectively, these advances are positioning polysulfide flow batteries as a viable solution for large-scale energy storage, with manufacturing processes that support both cost reduction and performance enhancement. As the industry continues to mature, further integration of digital manufacturing and materials innovation is expected to drive even greater adoption in the coming years.
Competitive Analysis: Leading Players, New Entrants, and Strategic Initiatives
The competitive landscape of polysulfide flow battery manufacturing in 2025 is characterized by a mix of established energy storage companies, innovative startups, and strategic partnerships aimed at scaling up production and improving technology. Leading players such as Sumitomo Chemical Co., Ltd. and Pennsylvania State University (notably through its research collaborations) have been at the forefront of advancing polysulfide-based flow battery systems, leveraging their expertise in chemical engineering and large-scale manufacturing. These organizations focus on enhancing battery efficiency, cycle life, and cost-effectiveness, which are critical for grid-scale energy storage applications.
New entrants, particularly startups spun out from academic research, are injecting fresh innovation into the sector. Companies like ESS Inc.—while primarily known for iron flow batteries—have signaled interest in polysulfide chemistries, exploring hybrid systems and licensing agreements to diversify their product portfolios. These newcomers often focus on niche applications or regional markets, using agile development cycles to rapidly prototype and test new electrolyte formulations and stack designs.
Strategic initiatives in 2025 are increasingly centered on partnerships and joint ventures. For example, collaborations between battery manufacturers and utility providers, such as those involving NGK Insulators, Ltd., aim to deploy pilot projects that demonstrate the scalability and reliability of polysulfide flow batteries in real-world grid environments. Additionally, supply chain alliances with chemical suppliers ensure a stable and cost-effective source of key materials, addressing one of the main barriers to mass adoption.
Intellectual property (IP) strategies are also shaping the competitive dynamics. Leading players are aggressively patenting novel membrane materials, electrolyte additives, and system integration techniques to secure technological advantages. Meanwhile, open innovation models—where research findings are shared among consortia—are gaining traction, particularly in Europe and Asia, to accelerate standardization and reduce development costs.
Overall, the competitive environment in 2025 is marked by a blend of technological innovation, strategic collaborations, and a focus on scaling up manufacturing to meet the growing demand for long-duration, sustainable energy storage solutions. The interplay between established manufacturers, agile startups, and cross-sector partnerships is expected to drive further advancements and commercialization of polysulfide flow battery technology.
Supply Chain & Raw Material Trends
The supply chain for polysulfide flow battery manufacturing in 2025 is shaped by evolving raw material sourcing, technological advancements, and global market dynamics. Polysulfide flow batteries rely primarily on sulfur and sodium or potassium salts, which are relatively abundant and inexpensive compared to the vanadium used in traditional flow batteries. This abundance reduces exposure to price volatility and supply constraints, a significant advantage for manufacturers seeking scalable and cost-effective energy storage solutions.
Sulfur, a byproduct of oil and gas refining, is widely available, with major producers including the United States, Russia, and China. The global sulfur supply chain is stable, but regional transportation and refining capacity can influence local availability and pricing. Battery-grade sodium and potassium salts are sourced from large-scale chemical producers, with INEOS Group and China National Offshore Oil Corporation (CNOOC) among the key suppliers. These chemicals are also used in other industries, so battery manufacturers must compete with agricultural and industrial demand, potentially impacting long-term contract negotiations and pricing.
In 2025, sustainability and traceability are increasingly important in the supply chain. Manufacturers are under pressure to ensure that raw materials are sourced responsibly, with minimal environmental impact. This has led to partnerships with suppliers who can provide documentation on the origin and processing of sulfur and salts, as well as efforts to reduce the carbon footprint of transportation and refining. Organizations such as the Responsible Mining Foundation are influencing industry standards, encouraging transparency and best practices.
Technological innovation is also affecting the supply chain. Advances in electrolyte formulation and membrane technology are enabling the use of lower-purity, less expensive raw materials without compromising battery performance. This flexibility allows manufacturers to diversify suppliers and reduce dependence on any single source or region. Additionally, some companies are exploring closed-loop recycling systems to recover and reuse sulfur and salts from spent electrolytes, further enhancing supply chain resilience and sustainability.
Overall, the polysulfide flow battery supply chain in 2025 is characterized by relative material abundance, increasing emphasis on sustainability, and ongoing innovation to reduce costs and environmental impact. These trends position polysulfide flow batteries as a promising solution for large-scale, long-duration energy storage applications.
Application Sectors: Grid Storage, Renewable Integration, and Industrial Use Cases
Polysulfide flow batteries are gaining traction across several application sectors due to their scalability, cost-effectiveness, and ability to support long-duration energy storage. In 2025, three primary sectors are driving demand and innovation in polysulfide flow battery manufacturing: grid storage, renewable energy integration, and industrial use cases.
Grid Storage: The need for reliable, large-scale energy storage solutions is critical for modern electricity grids, especially as they transition to accommodate more variable renewable energy sources. Polysulfide flow batteries offer high energy capacity and flexible scalability, making them suitable for grid-level applications such as load leveling, frequency regulation, and peak shaving. Utilities and grid operators, such as National Grid and Southern Company, are exploring flow battery systems to enhance grid resilience and defer costly infrastructure upgrades.
Renewable Integration: The intermittent nature of solar and wind power presents challenges for consistent energy supply. Polysulfide flow batteries can store excess renewable energy generated during periods of high production and release it during demand peaks or low generation periods. This capability supports higher penetration of renewables into the energy mix, helping countries and utilities meet decarbonization targets. Companies like Siemens Energy and Enel Green Power are actively investigating flow battery solutions to stabilize renewable-heavy grids and maximize the value of clean energy assets.
Industrial Use Cases: Beyond the grid, polysulfide flow batteries are being adopted in industrial settings where reliable backup power and energy management are essential. Manufacturing plants, data centers, and remote mining operations benefit from the batteries’ ability to deliver sustained power over long durations and withstand frequent cycling. Industrial technology providers such as Siemens and GE are collaborating with battery manufacturers to integrate flow battery systems into microgrids and behind-the-meter applications, improving operational efficiency and reducing reliance on diesel generators.
As manufacturing processes mature and costs decline, polysulfide flow batteries are expected to play an increasingly vital role across these sectors, supporting the global transition to more resilient, sustainable, and flexible energy systems.
Regulatory Environment and Policy Impact
The regulatory environment for polysulfide flow battery manufacturing in 2025 is shaped by evolving energy storage policies, environmental standards, and safety regulations. Governments worldwide are increasingly recognizing the role of flow batteries in supporting grid stability and renewable energy integration, prompting the development of specific guidelines and incentives for their production and deployment. In the United States, the U.S. Department of Energy has included flow batteries in its long-duration energy storage initiatives, offering research funding and pilot project support. Similarly, the European Union’s European Commission has established frameworks to accelerate the adoption of advanced storage technologies, including flow batteries, under its Green Deal and Horizon Europe programs.
Manufacturers of polysulfide flow batteries must comply with a range of environmental and safety regulations. These include the REACH Regulation in the EU, which governs the use of chemical substances, and the Resource Conservation and Recovery Act (RCRA) in the U.S., which addresses hazardous waste management. Polysulfide electrolytes, while less toxic than some alternatives, still require careful handling and containment to prevent environmental contamination. Regulatory agencies are increasingly mandating lifecycle assessments and end-of-life recycling plans for battery systems, pushing manufacturers to design for recyclability and minimal environmental impact.
Policy incentives play a significant role in shaping the market for polysulfide flow batteries. Tax credits, grants, and preferential grid access for energy storage projects are being implemented in several jurisdictions. For example, the U.S. Internal Revenue Service offers tax deductions for commercial energy storage installations, while the UK Department for Energy Security and Net Zero supports demonstration projects and market entry for innovative storage technologies.
Looking ahead, the regulatory landscape is expected to become more harmonized, with international standards for flow battery safety and performance under development by organizations such as the International Electrotechnical Commission (IEC). This will facilitate cross-border trade and accelerate the global adoption of polysulfide flow battery technology, provided manufacturers remain agile in adapting to new compliance requirements and sustainability expectations.
Investment, M&A, and Funding Trends
The landscape of investment, mergers and acquisitions (M&A), and funding in polysulfide flow battery manufacturing is evolving rapidly as the global energy storage market seeks scalable, cost-effective solutions for grid and industrial applications. In 2025, the sector is witnessing increased interest from both strategic investors and venture capital, driven by the growing demand for long-duration energy storage and the limitations of lithium-ion technologies in large-scale deployments.
Major energy and chemical companies are actively exploring partnerships and acquisitions to secure a foothold in the polysulfide flow battery value chain. For example, Siemens Energy AG and SABIC have signaled interest in flow battery technologies, including polysulfide chemistries, as part of their broader decarbonization and grid modernization strategies. These collaborations often focus on joint development agreements, technology licensing, and pilot-scale manufacturing investments.
Venture capital and private equity funding rounds in 2025 are increasingly targeting startups and scale-ups specializing in advanced polysulfide electrolytes, membrane technologies, and system integration. Notable examples include investments in companies like ESS Inc., which, while primarily known for iron flow batteries, has expanded its research into alternative chemistries such as polysulfide to address market needs for lower-cost, longer-duration storage. Funding is typically directed toward scaling up manufacturing capacity, optimizing supply chains, and accelerating commercialization timelines.
Government-backed initiatives and public-private partnerships are also playing a significant role. Agencies such as the U.S. Department of Energy and the European Commission Directorate-General for Energy are providing grants and incentives to support pilot projects and domestic manufacturing of polysulfide flow batteries, aiming to reduce reliance on imported critical minerals and foster local innovation ecosystems.
M&A activity is expected to intensify as established battery manufacturers and energy storage integrators seek to diversify their portfolios. Strategic acquisitions of technology startups with proprietary polysulfide formulations or advanced manufacturing processes are becoming more common, as companies aim to accelerate time-to-market and secure intellectual property advantages in a competitive landscape.
Overall, the investment and funding environment for polysulfide flow battery manufacturing in 2025 is characterized by a blend of strategic corporate moves, robust venture capital interest, and supportive government policies, all converging to drive the commercialization and scale-up of this promising energy storage technology.
Challenges, Risks, and Barriers to Adoption
The manufacturing of polysulfide flow batteries faces several significant challenges, risks, and barriers that impact their widespread adoption and commercial viability. One of the primary technical challenges is the management of polysulfide crossover through the membrane, which can lead to capacity loss and reduced efficiency over time. Developing robust, selective membranes that can withstand the corrosive nature of polysulfide electrolytes without significant degradation remains a key research focus for manufacturers and academic institutions alike (National Renewable Energy Laboratory).
Material compatibility is another critical issue. Polysulfide solutions are highly corrosive, necessitating the use of specialized materials for tanks, pumps, and piping. This increases both the complexity and cost of manufacturing, as well as the need for ongoing maintenance. The sourcing and processing of these corrosion-resistant materials can also present supply chain risks, especially as demand for flow batteries grows (BASF SE).
From a manufacturing perspective, scaling up production from laboratory or pilot-scale to full commercial scale introduces additional barriers. Uniformity in electrolyte composition, quality control of membrane fabrication, and the integration of balance-of-plant components all require significant investment in process engineering and automation. These factors can slow down the rate at which new manufacturing capacity comes online and may deter new entrants from investing in the sector (Sandia National Laboratories).
Economic risks are also present. The cost of polysulfide flow batteries must compete with established technologies such as lithium-ion and vanadium redox flow batteries. Fluctuations in the price of raw materials, particularly sulfur and supporting chemicals, can impact the overall cost structure and profitability of manufacturing operations. Additionally, the lack of standardized designs and industry-wide best practices can lead to inefficiencies and increased costs for early adopters (U.S. Department of Energy).
Finally, regulatory and safety considerations pose barriers to adoption. The handling and storage of large volumes of polysulfide solutions require compliance with environmental and safety regulations, which can vary by region and add to the complexity of deployment. Overcoming these challenges will require coordinated efforts between manufacturers, researchers, and regulatory bodies to develop safer, more cost-effective, and scalable manufacturing processes.
Future Outlook: Innovation Roadmap and Market Opportunities
The future outlook for polysulfide flow battery manufacturing in 2025 is shaped by accelerating innovation and expanding market opportunities, driven by the global demand for scalable, long-duration energy storage. As renewable energy integration intensifies, polysulfide flow batteries are gaining attention for their potential to deliver cost-effective, safe, and flexible grid-scale storage solutions. Key players in the sector are investing in research to address challenges such as electrolyte stability, membrane selectivity, and system efficiency, with a focus on reducing costs and improving cycle life.
Innovation roadmaps for 2025 emphasize the development of advanced electrode materials, improved membrane technologies, and optimized system architectures. Companies are exploring hybrid chemistries and novel additives to enhance the solubility and reversibility of polysulfide species, aiming to boost energy density and operational reliability. Automation and digitalization of manufacturing processes are also expected to streamline production, lower costs, and ensure consistent quality, making large-scale deployment more feasible.
Market opportunities are expanding beyond traditional utility-scale storage. Polysulfide flow batteries are being positioned for use in microgrids, commercial and industrial backup systems, and renewable energy smoothing applications. The modularity and scalability of these systems allow for tailored solutions across diverse sectors, from remote communities to urban infrastructure. Strategic partnerships between battery manufacturers, renewable project developers, and grid operators are anticipated to accelerate commercialization and deployment.
Supportive policy frameworks and funding initiatives from governments and international organizations are further catalyzing market growth. For example, the U.S. Department of Energy and the European Commission have both identified flow batteries as a priority technology for achieving net-zero targets and enhancing grid resilience (U.S. Department of Energy, European Commission). In Asia, countries like China and Japan are investing in domestic manufacturing capabilities and pilot projects to establish leadership in the global flow battery market (China Southern Power Grid, New Energy and Industrial Technology Development Organization (NEDO)).
Looking ahead, the polysulfide flow battery sector is poised for significant growth in 2025, underpinned by technological advancements, supportive policy environments, and a broadening range of applications. Continued innovation and collaboration across the value chain will be critical to unlocking the full market potential of this promising energy storage technology.
Appendix: Methodology, Data Sources, and Glossary
This appendix outlines the methodology, data sources, and glossary relevant to the analysis of polysulfide flow battery manufacturing in 2025.
- Methodology: The research combines primary and secondary data collection. Primary data was gathered through interviews with technical experts and representatives from leading manufacturers such as Sumitomo Chemical Co., Ltd. and Universal Solutions. Secondary data includes technical papers, patent filings, and official publications from organizations like the International Energy Agency (IEA) and U.S. Department of Energy. Manufacturing process details were cross-verified with published technical standards and supplier documentation.
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Data Sources: Key data sources include:
- Official product documentation and technical datasheets from polysulfide flow battery manufacturers (redT energy, Sumitomo Chemical Co., Ltd.).
- Industry guidelines and market updates from the Energy Storage News and IEA.
- Regulatory and safety standards from the International Organization for Standardization (ISO) and UL Solutions.
- Academic research accessed via open-access journals and university repositories.
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Glossary:
- Polysulfide Flow Battery: A type of redox flow battery using polysulfide ions as the active material in one or both electrolytes.
- Electrolyte: The liquid medium in which ions move between electrodes during charge and discharge cycles.
- Stack: The assembly of electrochemical cells where the redox reactions occur.
- Balance of Plant (BoP): All supporting components and systems required for battery operation, excluding the electrochemical stack.
- Round-Trip Efficiency: The ratio of energy output to energy input during a complete charge-discharge cycle.
All data and terminology are consistent with the latest industry standards and official documentation as of 2025.
Sources & References
- Sumitomo Chemical Co., Ltd.
- NGK Insulators, Ltd.
- Siemens Energy AG
- International Energy Agency (IEA)
- SGL Carbon
- Siemens
- Bosch
- BASF
- INEOS Group
- Responsible Mining Foundation
- National Grid
- Southern Company
- Enel Green Power
- GE
- European Commission
- REACH Regulation
- U.S. Internal Revenue Service
- UK Department for Energy Security and Net Zero
- European Commission Directorate-General for Energy
- National Renewable Energy Laboratory
- Sandia National Laboratories
- European Commission
- New Energy and Industrial Technology Development Organization (NEDO)
- redT energy
- Energy Storage News
- International Organization for Standardization (ISO)
- UL Solutions
