由于电池电解质中的辅溶剂不平衡造成的过度电位:在EMC:EC中LiPF6
Taeho Jung1,2, Andrew A Wang3, Charles W Monroe1,2
1Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, U.K.
ACS omega
|June 16, 2023
概括
液态离子电池模型经常忽略辅溶剂效应. 本研究量化了乙基甲基碳酸盐 (EMC) 和乙烯碳酸盐 (EC) 混合物的液结电位,揭示了来自不均溶剂比率的显著电压影响.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 液态离子电池电解质通常使用辅溶剂混合物.
- 现有的电化学运输模型往往将它们简化为单溶剂近似.
- 这种简化忽略了非均的辅溶剂比率对电池电压的潜在影响.
研究的目的:
- 为了研究和量化三元电解质混合物的液体连接潜力.
- 扩展现有的模型,用于预测乙基甲基碳酸盐 (EMC),乙烯碳酸盐 (EC) 和LiPF6系统中的连接潜力.
- 根据不可逆转的热力学,为这些电解质开发一个更准确的运输模型.
主要方法:
- 执行了固定参考度细胞测量.
- 两极化了辅溶剂比率以诱导液体结合潜力.
- 将之前报告的连接电位相关性扩展到三元组合.
- 开发了一种基于不可逆转热力学的运输模型.
主要成果:
- 由于两极化辅溶剂比率,观察到可观的液体结合潜力.
- 扩展了EMC:LiPF6连接电位相关性,以覆盖显著的三元组合空间.
- 报告了EC和LiPF的连接系数6.
- 证明离子电流诱导溶剂迁移.
结论:
- 不均的辅溶剂比率显著影响液态离子电池中的电池电压.
- 拟议的运输模型和连接系数提供了更准确的电解质表现行为.
- 了解溶剂迁移对于优化电池性能和安全至关重要.
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