溶剂盐中电解质中的异质协调使得高转移数成为可能
Anne Hockmann1,2, Florian Ackermann1, Diddo Diddens1,3
1Institute of Physical Chemistry, University of Münster, Corrensstraße 28/30, 48149 Münster, Germany. schoenho@uni-muenster.de.
Faraday discussions
|July 18, 2024
概括
溶剂盐电解质中的高转移数是通过异质离子协调实现的. 这种异质性解释了异常的离子流动性,这对于先进的电池开发至关重要.
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
- 物理化学 物理化学
背景情况:
- 溶剂盐 (SiS) 电解质为下一代电池提供高转移数 (tLi).
- 了解离子运输和协调是优化SiS电解质性能的关键.
研究的目的:
- 研究LiTFSI,DME和DOL三元电解质系统的传输特性和协调结构.
- 分析高度的传输机制,包括SIS模式.
- 阐明Li+协调异质性与运输行为之间的关系.
主要方法:
- 电泳性NMR (eNMR) 用于确定物种的移动性.
- 拉曼光谱和NMR光谱用于结构分析.
- 分子动力学 (MD) 模拟以建模Li+协调.
主要成果:
- 在SiS电解质中观察到的Li+转移数 (tLi) 为0.73.
- 在SiS区域中,中性DME流动性超过Li+流动性 (μDME>μLi).
- 在SiS区域确定了异质的Li+协调环境,影响Li+迁移速度.
- DME 作为双质联结体,而 TFSI 和 DOL 作为桥接联结体.
结论:
- +协调异质性是异质+运输和SiS电解质中高tLi的基础.
- 观察到Li+和离子 (Onsager系数 σ+- ≈0) 的有效动态解.
- 这些发现为改善电池应用提供了对有效离子运输的更深入的见解.
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