Related Experiment Video
Updated: May 29, 2026
09:49
A Protocol for Electrochemical Evaluations and State of Charge Diagnostics of a Symmetric Organic Redox Flow Battery
Published on: February 13, 2017
Bio-inspired relay catalysis for aqueous redox flow batteries
Jiafeng Lei1, Yaqin Zhang2, Weixing Wu3
1Electrochemical Energy and Interfaces Laboratory, Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
Nature Communications
|May 27, 2026
Summary
Relay catalysis enhances aqueous redox flow batteries by using sequential catalysts to boost reaction rates and energy efficiency. This strategy improves capacity utilization and battery stability for long-duration energy storage.
Area of Science:
- Electrochemistry
- Materials Science
- Energy Storage
Background:
- Aqueous redox flow batteries are key for long-duration energy storage.
- Current designs face challenges with slow reaction kinetics, low energy efficiency, and poor capacity utilization.
Purpose of the Study:
- To introduce relay catalysis as a universal strategy for high-performance aqueous redox flow batteries.
- To overcome the trade-off between overpotential and catalytic rate in energy storage systems.
Main Methods:
- Inspired by biological electron transfer, relay catalysis uses a two-step catalytic process.
- A low-overpotential catalyst initiates the reaction, followed by a high-activity catalyst.
Main Results:
- Demonstrated polysulfide-ferrocyanide flow batteries with near-complete polysulfide utilization (64 Ah L⁻¹).
- Achieved high stability over 3 months (>500 cycles) with minimal decay rates.
- Extended the relay catalysis strategy to organosulfide- and azo-based batteries.
Conclusions:
- Relay catalysis offers a transformative platform for designing advanced flow batteries.
- This approach redefines homogeneous catalysis for energy storage, enhancing performance and scalability.
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