在模型阳极与液态电池电解质的模型上,固体电解质间相的长期多孔性
Jonas Grill1, Jelena Popovic-Neuber2
1Department of Energy and Petroleum Engineering, University of Stavanger, Stavanger, Norway.
Communications chemistry
|December 20, 2024
概括
稳定的固体电解质间相 (SEI) 对电池性能至关重要. 这项研究揭示了在各种电解质中的阳极上早期的SEI形成,并分析了其特性,为改善电池寿命提供了见解.
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
- 电池技术 电池技术
背景情况:
- 稳定的固体电解质间相 (SEI) 对电池电极循环和保质期至关重要.
- 阳极上的SEI形成通常在循环后进行研究,而不是在开放电路条件下.
研究的目的:
- 在接近开放电路条件下的阳极上研究液体/固体SEI的形成和行为.
- 分析电解质组成对SEI特性和长期稳定性的影响.
主要方法:
- 使用了带有电极的对称电池.
- 使用温度依赖的电化学阻抗光谱 (EIS) 来测量SEI激活能量.
- 系统地研究了各种电解质配方 (碳酸盐,基于甘氨酸的,添加剂,含水量).
主要成果:
- 液体/固体SEI在阳极上形成,甚至在初始循环之前.
- 基于glyme的电解质比基于碳酸盐的电解质产生更多孔的SEI.
- 乙烯碳酸盐的添加提高了SEI的稳定性,并降低了glyme电解质中的电阻;少量的水会产生更密集的SEI.
结论:
- 在开放电路条件下,早期SEI形成对电池性能产生重大影响.
- 电解质工程,特别是使用乙烯碳酸等添加剂,可以优化SEI特性,以提高阳极稳定性和电池寿命.
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