富含的电解质添加剂,用于在低温下实现无树的阳极
Yan Wang1, Longtao Ren1, Qiaoli Zhang1
1College of Chemistry, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
ACS applied materials & interfaces
|August 30, 2024
概括
甲基三酸 (MTFA) 添加剂通过形成保护性固体电解质介相 (SEI) 层来稳定金属阳极. 这提高了电池的性能,并使得可靠的低温运行.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 金属阳极对于高能量密度电池至关重要,但受到界面不稳定性和树生长的影响.
- 这些问题限制了实际应用和安全操作,特别是在低温下.
研究的目的:
- 开发一种用于稳定金属阳极的新型电解质添加剂.
- 为了提高金属电池的接口性能和低温性能.
主要方法:
- 引入甲基三乙酸盐 (MTFA) 作为一种以为基础的电解质中的电解质添加剂.
- 形成一个富含LiF的in situ复合体固体电解质间相 (SEI) 层,具有灵活的以基为基础的矩阵.
- 在各种温度条件下,对立式Li的电化学测试和Li的完整LiFePO4电池.
主要成果:
- 由MTFA衍生的SEI层具有高离子导电性和机械稳定性,有效调节沉积并抑制树突.
- 立体二极管对称细胞的寿命延长 (>在室温下5000小时,在-20°C下800小时),超电位较低.
- 体体LiFePO4全细胞显示出极好的循环稳定性 (在200个循环中每周期衰减0.096%的容量) 和高库伦比效率 (>99%在-20°C).
结论:
- MTFA是一种有效的电解质添加剂,用于在金属阳极上创建稳定和导电性的SEI层.
- 这种方法显著提高了电池循环性能,并使低温可靠运行.
- 这项研究提出了一个有前途的战略,通过电解质工程来推进金属电池技术.
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