相关的离子溶解结构和电极潜在温度系数
Hansen Wang1, Sang Cheol Kim1, Tomás Rojas2,3
1Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
Journal of the American Chemical Society
|January 28, 2021
概括
电极潜力的温度系数揭示了对离子行为的关键见解. 这项研究将这些系数与离子溶解联系起来,为电池电解质提供了一种新的选方法.
科学领域:
- 电化学
- 材料科学
- 电池技术
背景情况:
- 电极电位的温度系数 (TC) 对于理解离子电池的热安全性和材料相位过渡至关重要.
- 单个电极电位TC的基本意义,特别是 (Li) /Li+电极,仍未得到充分研究.
研究的目的:
- 研究离子溶解对/+电极电位的贡献.
- 在各种电解质中建立Li/Li+电极电位TC和离子溶解结构之间的相关性.
- 证明Li/Li+电极电位TC作为新电池电解质选工具的实用性.
主要方法:
- 在不同溶剂,离子和盐度的电解质配方中对Li/Li+电极电位TC进行比较分析.
- 使用*ab initio*分子动力学模拟来验证TC和离子溶解结构之间的相关性.
主要成果:
- 在沉积/间隔过程中的离子溶解过程被证明是由于实质性变化导致/+电极电位的显著贡献.
- 测量到的电极电位和不同电解质内的特定离子溶解结构之间建立了直接的相关性.
- 这项研究证实TC为离子溶解环境提供了宝贵的见解.
结论:
- /+电极电位TC受到离子溶解的显著影响.
- 电极电位TC作为离子溶解环境的有价值指标.
- 测量Li/Li+电极电位TC可以有效地作为选工具来设计下一代离子和金属电池的先进电解质.
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