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Boosting Electrolytic MnO2-Zn Batteries by a Bromine Mediator
Xinhua Zheng1, Yongchao Wang2, Yan Xu1
1Department of Applied Chemistry, School of Chemistry and Materials Science, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
Nano Letters
|October 11, 2021
Summary
Researchers developed a high-performance aqueous manganese dioxide-zinc (MnO2-Zn) battery using a bromine redox mediator. This innovation significantly enhances conductivity and extends the battery
Area of Science:
- Electrochemistry
- Materials Science
- Energy Storage
Background:
- Aqueous electrolytic MnO2-Zn batteries are promising for next-generation energy storage.
- Limited MnO2 conductivity hinders long service life and high areal capacities.
Purpose of the Study:
- To enhance the electrochemical performance of MnO2-Zn batteries.
- To overcome the conductivity limitations of MnO2 electrodes.
Main Methods:
- Introduction of a bromine (Br2) redox mediator into the MnO2-Zn battery system.
- Electrochemical characterization and performance testing of the modified battery.
Main Results:
- The MnO2/Br2-Zn battery achieved a high discharge voltage of 1.98 V and capacity of ~5.8 mAh cm-2.
- Demonstrated excellent rate performance (20 C) and long-term stability (>600 cycles).
- Scaled-up battery showed stable cycling (100 cycles) with practical energy density (~32.4 Wh kg-1) and low cost (<15 US$ kWh-1).
Conclusions:
- The bromine redox mediator effectively enhances MnO2-Zn battery performance.
- This approach offers a viable pathway for developing high-performance, cost-effective large-scale energy storage solutions.
- The design strategy is adaptable to other battery systems.
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