一种完全甲基化循环以太溶剂使得石墨阳极在低温下循环运行
Yongxin Ma1, Minghao Huang1, Yejuan Xue1
1School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, P. R. China.
ACS applied materials & interfaces
|April 24, 2024
概括
研究人员开发了一种用于离子电池 (LIB) 的新电解质,可以提高低温性能. 这种新型电解质增强了石墨阳极的稳定性和离子转移,提高了电池容量保留和在寒冷条件下循环寿命.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 离子电池 (LIB) 在低温下面临显著的容量损失和极化.
- 这是由于高的Li+解溶能障碍和缓慢的Li+在固体电解质接口 (SEI) 上的转移.
研究的目的:
- 设计一种电解质,使石墨阳极接口稳定,并在低温下增强反应动力学.
- 通过电解质工程来提高LIBs的低温性能.
主要方法:
- 使用2,2,4,4,5,5-甲基-1,3-二氧化 (HMD) 和乙烯碳酸盐 (FEC) 开发了一种高度离子导电的电解质.
- 研究了电解质的溶解结构及其对Li+溶解和SEI形成的影响.
- 测试了在低温条件下使用新的电解质测试玉玉石墨电池的性能.
主要成果:
- 基于HMD的电解质形成了一个阳离子主导的溶解结构,加速了Li+溶解.
- 形成了一层富含LiF的SEI层,防止溶剂协同和改善离子迁移.
- 带有新电解质的电池在227个周期内保持了93.8%的容量,在20°C下200个周期后保持了81%,超过了传统电解质的性能.
结论:
- 阳离子主导的溶解电解质为低温LIB提供了一个有前途的策略.
- 设计的HMD/FEC电解质在寒冷条件下显著提高了石墨阳极性能.
- 这项工作为设计用于低温储能应用的先进电解质提供了宝贵的见解.
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