脱阳离子使LiPF6基于电解质的溶解化学控制向低温离子电池转向
Song Yuan1,2, Shengkai Cao3, Xi Chen1,2
1Institute of Flexible Electronics Technology of THU, Tsinghua University, Jiaxing, Zhejiang, 314000, P. R. China.
Advanced materials (Deerfield Beach, Fla.)
|January 14, 2024
概括
一种新的电解质添加剂提高了离子电池在零度以下温度的性能. 通过修改六酸 (LiPF6) 和酸盐添加剂的溶解结构,可显著减少容量衰变,使低温运行稳定.
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) 的零度以下温度运行受到缓慢的界面动力学阻碍,导致严重的容量衰减.
- 目前使用高溶性盐的解决方案面临着诸如当前收集器腐蚀和高成本等挑战.
研究的目的:
- 为使用六酸 (LiPF6) 的低温LIB开发一个具有成本效益的电解质策略.
- 为了改善界面动力学和减轻LIB在零度以下温度下运行的容量衰减.
主要方法:
- 将酸盐 (NO3-) 添加剂添加到基于LiPF6的电解质中,以创建特定的离子对和聚合物溶解结构.
- 在-20°C下对石墨 (Gr) 阳极和LiCoO2/Gr全电池进行电化学性能评估.
主要成果:
- 酸盐添加剂在低温下显著降低了界面能量屏障.
- 石墨阳极在-20°C时表现出约72.3%的容量保留,性能优于常规电解质.
- LiCoO2/Gr全电池在 -20 °C下实现了100个周期的稳定循环,并进行了抑制的涂层.
结论:
- 拟议的基于LiPF6的电解质与酸盐添加剂为低温LIB应用提供了一个有希望的新方法.
- 这一策略有效地解决了容量衰减问题,并确保在零下环境中稳定的电池性能.
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