Global Flow Battery Industry White Paper: Path to Large-Scale Long-Duration Energy Storage

This white paper, published by Boston Consulting Group in November 2025, explores the rise of flow batteries as a key technology for large-scale long-duration energy storage. It highlights the unique advantages of flow batteries, such as decoupled energy and power design, high safety, long cycle life, and scalability for durations of 4 hours or more. The document traces the technical principles of redox flow batteries, compares mainstream energy storage technologies, and analyzes vanadium-based and alternative chemistries like iron-chromium, iron salt, and zinc-bromine systems. It examines the global competitive landscape, key development milestones, and driving factors behind the industry's growth. The paper also provides economic and commercialization analysis, including cost trends, market size evolution, and three breakthrough pathways for scaling up. Despite currently representing less than 2% of global electrochemical storage capacity, flow batteries are entering a large-scale demonstration phase, particularly in China, driven by policy support and supply chain improvements. The authors conclude that flow batteries are poised to become a transformative force in the next wave of energy technology, enabling grid peak shaving and industrial energy storage applications.