在硫电池电解质中控制聚硫化物溶解,扩散和反应的盐度控制
N Tan Luong1, Aginmariya Kottarathil1,2, Władysław Wieczorek2,3
1Department of Physics, Chalmers University of Technology, 412 96 Gothenburg, Sweden.
概括
高度的电解质减少了-硫 (Li-S) 电池中的聚硫化物 (PS) 溶解和迁移. 这项研究揭示了盐度如何影响PS行为,改善Li-S电池的稳定性和寿命.
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:
- 硫 (Li-S) 电池面临聚硫化物 (PS) 溶解的挑战,影响性能和寿命.
- 了解PS溶解和迁移机制,特别是在不同的充电状态下 (SOC),对于Li-S电池的改进至关重要.
研究的目的:
- 研究高度的电解盐对Li-S电池中的多硫化物溶解度和运输的影响.
- 阐明不同度下长链和短链多硫化物和三硫基的行为.
主要方法:
- 使用运行式拉曼光谱法实时监测聚硫化物种.
- 在 DME:DOL (1:1,v/v) 电解质中检查了广泛的 LiTFSI 度 (0.3-7.0 m).
主要成果:
- 电解质盐度的增加降低了可溶性,并减缓了阳极中的PS二离子 (S4-82-) 和三硫基 (S3•-) 的运输.
- S3•-的度比S62-显著下降,这表明缩的电解质中抑制了激素的形成.
- 由于高盐度控制PS行为,观察到局部溶解结构的变化.
结论:
- 高度的电解质盐有效地减轻了Li-S电池中的聚硫化物溶解和迁移.
- 了解溶解结构对聚硫化物动态的影响是提高Li-S电池性能的关键.
- 这项研究为设计先进的Li-S电池电解质提供了关键的机械见解.
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