基于伊米达的盐LiHDI作为导电解质的固体电解质相间稳定添加剂
Marek Broszkiewicz1, Bartosz Brzozowski1, Tomasz Trzeciak1
1Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
Molecules (Basel, Switzerland)
|February 24, 2024
概括
4,5-dicyano-2-(n-heptafluoropropyl) imidazolide (LiHDI) 通过稳定固体电解质间相来提高离子电池的性能. 这种添加剂提高了容量保留和热稳定性,为传统添加剂提供了有希望的替代品.
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
- 电池技术 电池技术
背景情况:
- 固体电解质间相 (SEI) 形成对于离子电池的寿命至关重要.
- 像乙烯碳酸盐 (FEC) 和乙烯碳酸盐 (VC) 这样的常规添加剂具有局限性.
- 开发新的SEI稳定添加剂对于提高电池性能至关重要.
研究的目的:
- 为了研究4,5-dicyano-2-(n-heptafluoropropyl) imidazolide (LiHDI) 作为离子电池中的SEI稳定剂添加剂的有效性.
- 为了比较LiHDI与常规添加剂 (FEC,VC) 和无添加剂的电解质的性能.
- 评估LiHDI对电解质特性,电化学性能和SEI组成的影响.
主要方法:
- 电化学测试包括室温和60°C的静电循环.
- 测量电解质导电性和细胞内部电阻.
- 在循环后对电极表面进行X射线光电子光谱 (XPS) 分析.
主要成果:
- LiHDI的化学和热稳定性与LiTDI的化学和热稳定性相当.
- LiHDI不会对电解质性能产生负面影响.
- LiHDI显著改善了石墨-LiFePO4电池的容量保留,超过了FEC-VC混合物,特别是在高温下.
- 内细胞抵抗与提高容量保留相关.
- 对XPS的分析显示,LiHDI对SEI的组成有影响.
结论:
- LiHDI是离子电池的高效SEI稳定添加剂.
- 与FEC-VC.相比,LiHDI提供了优越的性能,特别是在高温下.
- LiHDI为提高电池周期寿命和稳定性提供了一个有希望的途径.
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