在电极和电解质中通过操作中子吸收以原子精度量化的时空量化
Peter-Paul R M L Harks1, Tomas W Verhallen2, Chandramohan George2,3
1Materials for Energy Conversion and Storage (MECS), Department of Chemical Engineering , Delft University of Technology , P.O. Box 5045, 2600 GA Delft , The Netherlands.
Journal of the American Chemical Society
|August 27, 2019
概括
中子深度分析揭示了聚硫化物如何移动和包含在硫 (Li-S) 电池中. 这有助于了解和改善Li-S电池的性能和寿命.
科学领域:
- 材料科学
- 电化学
- 能量储存
背景情况:
- -硫 (Li-S) 电池具有较高的理论能量密度,但周期寿命较短.
- -S电池的性能衰退主要是由于聚硫化物溶解和穿.
- 缺乏现场分析技术阻碍了对Li-S细胞中的多硫化物动态的理解.
研究的目的:
- 在空间和时间上可视化Li-S电极中的 (Li) 分布.
- 获得 Li-S 电池组件中聚硫化物调节的机械洞察力.
- 将聚硫化物行为与电池容量和寿命相关联.
主要方法:
- 使用6Li同位素进行直接空间Li分析的中子深度分析 (NDP).
- 研究了三种类型的Li-S电极:碳硫,碳硫与氧化物 (LTO) 以及碳硫与LTO膜.
- 分析了聚硫化物在工作中的迁移,吸附和封闭.
主要成果:
- 提供了聚硫化物迁移,吸附和限制在Li-S电极中的直接空间证据.
- 证明了电极组成 (LTO添加,LTO膜) 对聚硫化物行为的影响.
- 将聚硫化物动态与观察到的Li-S电池容量和循环寿命联系起来.
结论:
- NDP是阐明Li-S电池机制的强大工具.
- 了解聚硫化物监管对于设计稳定且持久的电池至关重要.
- 这些发现为高能耗,安全和成本效益的Li-S电池提供了合理的电极设计指南.
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