在Mg电池的双层中电解质反应:一个接口潜在依赖的DFT研究
Anja Kopač Lautar1,2, Jan Bitenc1, Tomaž Rejec2,3
1Department of Materials Chemistry, National Institute of Chemistry, 1000 Ljubljana, Slovenia.
Journal of the American Chemical Society
|February 8, 2020
概括
在金属电池中,电解质降解即使不接触表面也会发生,这挑战了以前的假设. 新的方法揭示了稳定的电池运行延长的潜在窗口.
科学领域:
- 电化学
- 材料科学
- 计算化学
背景情况:
- 金属电池提供高能量密度,但电解质稳定性面临挑战.
- 电解质降解是阻碍Mg金属电池实际应用的主要限制.
研究的目的:
- 研究Mg金属电池的溶剂电解质的电化学降解机制.
- 了解电解质分解路径及其对Mg金属电池性能的影响.
- 为预测和改善电解质稳定性制定理论框架.
主要方法:
- 使用大规范密度函数理论 (DFT) 来建模电解质行为.
- 在双层区域内分析电化学反应.
- 确定了电解质和沉积的热力学稳定性.
主要成果:
- 在双层中确定了显著的电解质反应,独立于直接接触Mg表面.
- 表明二氧化乙 (DME) 和乙烯碳酸盐 (EC) 在Mg2+/Mg0降解之前会热力学分解.
- 定义了一个扩展的运行潜力窗口 (OPW),使Mg沉积超出热力学极限.
结论:
- 双层电解质分解是Mg电池故障的一个关键因素.
- 开发的潜在依赖的DFT方法准确地预测了降解产品和机制.
- 该方法为设计多价电池和储能装置的稳定电解质提供了指导方针.
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