A combined flow field design for dual optimization of mass transfer and pressure drop in anion exchange membrane water electrolysis

Anion exchange membrane water electrolysis (AEMWE) is a competitive technology for large-scale green hydrogen production. As a core component of the electrolyzer, the flow field is crucial for optimizing reactant distribution, enhancing mass transfer efficiency, and reducing system energy consumption. However, traditional single-structure flow fields inherently face a trade-off between mass transfer efficiency and pressure drop. To address these issues, this study proposes a novel combined flow field (CFF) for AEMWE. The performance of CFF is validated through mass transfer visualization, pressure drop measurement, and electrochemical characterization. Results show that the CFF outperforms parallel flow field (PFF), serpentine flow field (SFF), and interdigitated flow field (IFF) in balancing mass transfer efficiency and pressure drop across different flow rates. Under realistic AEMWE operating conditions, the CFF reduces pressure drop compared to SFF and improves cell electrochemical performance—exhibiting a lower cell voltage at a typical current density and a significant reduction in mass transport overpotential relative to traditional flow fields. Therefore, this study provides insights for future flow field design in high-performance water electrolysis.