用于低温离子电池的碳酸基电解质的度控制
Song Gao1, Kang Wang1, Liying Wang1
1Key Laboratory of Advanced Structural Materials, Ministry of Education & Advanced Institute of Materials Science, Changchun University of Technology, Changchun, 130012, P. R. China.
Chemistry (Weinheim an der Bergstrasse, Germany)
|July 23, 2024
概括
这项研究为离子电池 (LIB) 引入了一种新型电解质,可以提高在低温下的性能. 新的电解质配方可确保电池在-40°C下稳定运行,克服了LIBs的一个关键挑战.
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
背景情况:
- 由于电解质失活,低温显著降低了离子电池 (LIB) 的性能.
- 在零度以下的温度下保持电化学稳定性的电解质的开发对于实际的LIB应用至关重要.
研究的目的:
- 设计一种耐低温的电解质,以提高LIB性能.
- 在低温下研究稳定的固体电解质接口 (SEI) 的形成.
主要方法:
- 使用乙烯 (EA) 和乙烯碳酸盐 (FEC) 作为溶剂的新型电解质的配方,二 (LiDFOB) 作为盐.
- 对金属阳极 (LMA) 和氧化物 (LCO) 阴极上SEI形成的分析.
- 电化学循环测试LIBs在-40°C和石墨/LCO电池在-25°C.
主要成果:
- 优化的电解质促进了富含LiF的SEI层的形成,增强了稳定性和Li+离子溶解.
- 带有新电解质的LIB在200个循环后在-40°C下保持了83.9%的容量.
- 石墨/LCO电池在-25°C下保持了90.3%的容量.
结论:
- 开发的电解质有效地解决了LIBs中低温性能降解的挑战.
- 这种具有成本效益的电解质可以在寒冷的环境中实现实用的LIB应用.
- 富含LiF的SEI层是实现在零度以下温度下稳定循环的关键.
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