Related Experiment Video
Updated: Jan 11, 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
10.9K
A Highly Reversible Redox Mediator Enables Long-Term Stability Alkaline Zinc-Iron Flow Batteries with Complete
Fangyuan Xiao1,2, Jiayou Ren3, Hongchao Zhang4
1Faculty of Materials Science and Energy Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, 518055, China.
Small (Weinheim an Der Bergstrasse, Germany)
|November 18, 2025
Summary
A novel redox mediator effectively dissolves inactive zinc in alkaline zinc-iron flow batteries (AZIFBs), enhancing cycling stability and suppressing hydrogen evolution for reliable energy storage.
Area of Science:
- Electrochemistry
- Materials Science
- Energy Storage
Background:
- Alkaline zinc-iron flow batteries (AZIFBs) are promising for long-duration energy storage.
- Inactive zinc accumulation (
- dead Zn
- ) degrades AZIFB performance and lifespan.
Purpose of the Study:
- To introduce a redox mediator (RM) that resolves dead Zn issues in AZIFBs.
- To enhance the cycling stability and efficiency of AZIFBs.
Main Methods:
- Introduction of 2-amino-3-hydroxyphenazine as a redox mediator.
- Electrochemical cycling and analysis of AZIFBs with the RM.
- Investigation of the RM's effect on zinc deposition and hydrogen evolution.
Main Results:
- The RM effectively dissolves accumulated dead Zn, preventing dendrite growth.
- The RM suppresses parasitic hydrogen evolution reaction (HER).
- AZIFBs with RM achieved over 2300 hours of stable cycling at 100% utilization.
Conclusions:
- 2-amino-3-hydroxyphenazine is a stable and effective RM for AZIFBs.
- The RM significantly improves battery cycling stability and efficiency.
- This approach enables high-performance, long-duration energy storage using AZIFBs.
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