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Updated: May 19, 2026
05:33
Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications
Published on: August 12, 2013
Polyprotic acid catholyte for high capacity dual-electrolyte Li-air batteries
Longjun Li1, Xinsheng Zhao, Yongzhu Fu
1Electrochemical Energy Laboratory & Materials Science and engineering Program, the University of Texas at Austin, Austin, Texas 78712, USA.
Physical Chemistry Chemical Physics : PCCP
|August 15, 2012
Summary
Phosphoric acid (H3PO4) acts as a proton donor in lithium-air cells, achieving high capacity and stable voltage. This dual-electrolyte system demonstrates promising performance for rechargeable batteries.
Area of Science:
- Electrochemistry
- Materials Science
- Energy Storage
Background:
- Lithium-air (Li-air) batteries are a promising next-generation energy storage technology.
- Developing efficient and stable catholytes is crucial for improving Li-air cell performance.
- Polyprotic acids offer potential as proton sources in electrochemical systems.
Purpose of the Study:
- To investigate the use of phosphoric acid (H3PO4) as a catholyte in dual-electrolyte Li-air cells.
- To evaluate the electrochemical performance, including capacity, voltage, rechargeability, and stability.
- To demonstrate the viability of H3PO4 as a proton-donating species in this system.
Main Methods:
- Utilizing a dual-electrolyte Li-air cell configuration.
- Employing phosphoric acid (H3PO4) as the catholyte.
- Using a lithium sulfate (Li2SO4) supporting electrolyte.
- Conducting electrochemical performance testing, including capacity and voltage measurements.
Main Results:
- Phosphoric acid (H3PO4) effectively donated three protons in the Li-air cell.
- The cell achieved a high capacity of 740 mA h g(-1).
- A stable average cell voltage of 3.3 V was maintained with good rechargeability and stability.
Conclusions:
- Phosphoric acid (H3PO4) is a viable and effective catholyte for dual-electrolyte Li-air cells.
- The demonstrated high capacity and stability highlight the potential of this system for advanced energy storage.
- This study contributes to the development of improved Li-air battery technologies.
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