碳酸盐溶剂电解质在酸阳极上的活性
Heonjae Jeong1,2, Christopher S Johnson3
1Department of Electronic Engineering, Gachon University, Seongnam, Gyeonggi 13120, South Korea.
ACS applied materials & interfaces
|September 18, 2025
概括
研究人员探索了离子电池 (LIB) 中阳极的电解质添加剂. 该研究发现,LiPF6与乙基甲基碳酸盐 (EMC) 中的乙烯碳酸盐 (VC) 具有最低的反应性,改善了电池的稳定性.
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
- 计算化学计算化学
背景情况:
- 阳极为离子电池 (LIB) 提供高容量,但受到体积膨胀和电解质不稳定的影响.
- 不均的固体电解质间相 (SEI) 形成阻碍了LIB性能和寿命.
- 计算模拟对于理解SEI机制和电解质行为至关重要.
研究的目的:
- 用阳极研究不同电解质组合物的反应性.
- 了解乙烯碳酸 (VC) 和乙烯碳酸 (FEC) 等电解质添加剂的作用.
- 为基于的LIB设计稳定电解质提供见解.
主要方法:
- 密度功能理论 (DFT) 和初始分子动力学 (AIMD) 模拟.
- 在电解质-系统中分析离子轨迹和电荷转移.
- 计算解离和形成能量以评估电解质活性.
主要成果:
- 在乙基甲基碳酸盐 (EMC) 中含有VC的LiPF6显示出与阳极的反应性最低.
- FEC和VC的影响因主要溶剂 (EMC或EC/EMC混合物) 而有所不同.
- 电解质反应性取决于阳极的化状态和电荷.
结论:
- 第一原则模拟为设计电解质提供了战略基础,这些电解质可以提高LIBs中的阳极的循环稳定性和日历寿命.
- 了解电解质-相互作用是克服高容量电池材料挑战的关键.
- 优化的电解质配方可以减轻SEI问题并提高电池的整体性能.
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