一个可逆和更高速率的Li-O2电池
Zhangquan Peng1, Stefan A Freunberger, Yuhui Chen
1School of Chemistry, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9ST, UK.
Science (New York, N.Y.)
|July 24, 2012
概括
研究人员开发了一种可充电的空气电池,配有二甲基硫氧化物电解质和金电极,实现95%的容量保留. 这一突破使得高度可逆的过氧化的形成和分解成为可能,从而改善了能量储存.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 可充电的空气 (Li-O(2) 电池在理论上提供比离子电池更高的特定能量.
- 高效的电池运行依赖于可逆过氧化物 (Li(2) O(2) 在阴极的形成/分解.
研究的目的:
- 研究一种新的电解质和电极组合,以实现稳定的Li-O(2) 电池循环.
- 为了提高Li(2) O(2) 循环的可逆性,用于实际的储能应用.
主要方法:
- 使用了一种二甲基硫氧化物 (DMSO) 电解液.
- 用一个多孔的金电极进行阴极研究.
- 进行了电化学循环测试,以评估容量保留和Li(2) O(2) 行为.
主要成果:
- 在100个周期内实现95%的容量保留,与以前的系统相比显著改善.
- 使用DMSO/黄金电极配置确认了高度可逆的Li(2) O(2) 形成和分解.
- 与碳电极相比,在黄金上观察到的Li(2) O(2) 氧化动态大约是碳电极的10倍.
结论:
- DMSO电解质和多孔黄金电极的组合使非水性Li-O(2) 电池能够稳定和可逆循环.
- 这一进步解决了O2电池技术的关键挑战,为更高能量密度的存储解决方案铺平了道路.
- 较快的Li(2) O(2) 氧化动力学表明更好的充电效率和功率能力.
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