硫化聚烯 (SPAN) 在使用碳酸盐电解质的硫电池中的降解行为:一项计算研究
S V Klostermann1, J Kappler2, A Waigum1
1Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany. kaestner@theochem.uni-stuttgart.de.
Physical chemistry chemical physics : PCCP
|March 13, 2024
概括
硫电池 (LSB) 显示出高能量密度的前景. 计算研究表明,硫化聚烯) 阴极通过稳定硫化核形成,防止了多硫化的穿.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 计算化学的计算化学
背景情况:
- 硫电池 (LSB) 提供高的理论能量密度,并利用丰富的硫.
- 聚硫化物穿机制通过影响硫氧化还原特性来阻碍LSB的性能.
- 电解质和阴极材料的选择显著影响LSB的电化学行为.
研究的目的:
- 通过使用硫化聚烯 (SPAN) 阴极在LSB中计算调查放电过程.
- 为了比较LSB放电期间固体Li2S与可溶Li2S的核化.
- 通过分析吉布斯自由能量来确定主导物种.
主要方法:
- 对LSB放电机制的计算研究.
- 吉布斯自由能量计算用于识别主导物种.
- 固体Li2S核化与可溶性Li2S的比较.
主要成果:
- 多个化步骤先于Li2S分离,抑制聚硫化物穿.
- 2S单位通过丰富的SPAN骨干上的核化来稳定.
- 计算的排放形状与实验数据一致,表明固体-固体过渡.
结论:
- SPAN阴极有效地稳定了Li2S核化,减轻了多硫化物穿.
- 2S与SPAN骨干之间的相互作用对电池性能至关重要.
- 在碳酸盐电解质中的Li-SPAN细胞中提出了直接的固体-固体过渡机制.
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