Long-duration energy storage is booming. Boasting abundant raw materials, controllable costs, high safety and decoupled power and capacity, iron-chromium flow batteries have become the most scalable technical route after all-vanadium systems. Since 2025, multiple projects over 10MW have been launched in China, while a 600MWh large-scale order in Europe has been signed and delivered, driving iron-chromium flow batteries into large‑scale commercialization. Yet key bottlenecks remain, including slow kinetics, hydrogen evolution, ion crossover and electrolyte incompatibility, making efficient, accurate and repeatable testing essential for technical and engineering breakthroughs.

With deep expertise in flow battery testing equipment, we target R&D pain points of iron-chromium systems and provide a full range of LAB products covering single-cell setups, test stacks and test platforms. Supporting material screening, mechanism study, performance validation and system integration with customized services, we deliver one-stop precision testing solutions to accelerate the industrialization of iron-chromium flow battery technology.

Single-Cell System: Iron-Chromium Core Materials Rapid Screener

The first step in iron-chromium R&D is to precisely identify the optimal combination of electrolyte, membrane, and electrode. ZH Energy’s modular single-cell system is designed specifically for fundamental flow battery research:

• Simple structure and easy assembly, ideal for high-frequency material comparison testing;

• Optimized flow field design for significantly improved energy efficiency;

• Multiple specifications available to accurately evaluate intrinsic material properties, eliminate operational interference, and rapidly iterate electrolyte formulations, verify membrane selectivity, and optimize electrode activity, securing the best material solution with reliable data.

Test Stack: Iron-Chromium Engineering Validation Bridge

As a core bridge between laboratory research and industrialization, iron-chromium systems impose stricter requirements on mass transfer, sealing and performance consistency. ZH Energy’s test stacks adopt commercial full-stack architecture with fully optimized flow fields and engineering validation:

• Verified by customers: energy efficiency >80% at power density of 100 mW/cm², highly consistent with industrial stack performance;

• Manufactured under ISO9001 standardized processes for excellent batch consistency;

• Optimized for high-temperature operating conditions of iron-chromium systems, effectively revealing engineering challenges such as uneven mass transfer, sealing issues and side reactions during scale-up, thereby reducing pilot-scale risks.

Test Platform: Iron-Chromium System Final Verification Station

Full-system validation under real operating conditions is essential prior to industrialization. ZH Energy's flow battery test platform integrates monitoring, testing and verification in one unit:

• Equipped with multi-dimensional sensors for full collection of key performance indicators;

• Modular design with flexible configurations from 1–5kW to 10–50kW, supporting customization;

• Capable of integrating temperature control, charge-discharge testing, PCS, SOC and other modules to simulate actual energy storage station operation, providing conclusive data support for the commercial deployment of iron-chromium flow batteries.

High-Throughput Solution: Iron-Chromium R&D Efficiency Accelerator

To meet the demand for parallel screening of diverse materials and parameters in iron-chromium R&D, ZH Energy offers a multi-channel single-cell test station (8 channels as standard):

• Parallel testing greatly increases experimental throughput with highly comparable data under identical conditions;

• Automated control minimizes human error and consumable waste;

• Full acquisition of EE, CE, capacity and decay curves supports rapid material iteration and mechanism research, significantly shortening R&D cycles.

To date, ZH Energy’s LAB series has served hundreds of flow battery manufacturers, research institutes and universities worldwide, strongly supporting R&D and mass production across multiple technical routes including all-vanadium, iron-chromium, iron-sulfur, zinc-iron, all-iron and organic systems. It has become a recognized test equipment partner in the long-duration energy storage sector.

As iron-chromium flow batteries enter a critical window for large-scale application, ZH Energy will continue to deliver precise, reliable and efficient testing solutions. We help overcome material and engineering bottlenecks for the iron-chromium route, accelerate the deployment of hundred-megawatt-level energy storage projects, and provide robust technical impetus for the high-quality development of long-duration energy storage.