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09:49
A Protocol for Electrochemical Evaluations and State of Charge Diagnostics of a Symmetric Organic Redox Flow Battery
Published on: February 13, 2017
A high-energy-density redox flow battery based on zinc/polyhalide chemistry
Liqun Zhang1, Qinzhi Lai, Jianlu Zhang
1Division of Energy Storage, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, PR China.
Chemsuschem
|January 21, 2012
Summary
This study introduces a novel zinc/polyhalide redox flow battery. It achieves 81% energy efficiency, offering high performance and energy density at a reasonable cost.
Area of Science:
- Electrochemistry
- Energy Storage Systems
- Materials Science
Background:
- Redox flow batteries (RFBs) are promising for grid-scale energy storage.
- Zinc-based RFBs offer potential for high energy density and low cost.
- Polyhalide electrolytes present unique electrochemical properties for RFBs.
Purpose of the Study:
- To develop and evaluate a novel zinc/polyhalide redox flow battery.
- To assess the performance metrics including energy efficiency, Coulombic efficiency, and voltage efficiency.
- To determine the potential of this technology for practical energy storage applications.
Main Methods:
- Fabrication of a zinc/polyhalide redox flow battery.
- Performance evaluation using charge-discharge cycling tests.
- Analysis of redox couples: Br(-) /ClBr(2-) in the positive half-cell and Zn/Zn(2+) in the negative half-cell.
Main Results:
- The battery demonstrated a high energy efficiency of 81%.
- Coulombic efficiency reached 96%, and voltage efficiency was 84%.
- The system exhibited stable charge-discharge cycling performance.
Conclusions:
- The developed zinc/polyhalide redox flow battery shows excellent performance characteristics.
- This technology offers a viable path towards high-performance, high-energy-density, and cost-effective energy storage.
- Further development could lead to practical implementation in grid-scale applications.
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