分子级阳离子和Li+共调通过聚合物分离器用于高速稳定的金属阳极
Shizhen Li1, Hangqi Yang1, Mengzi Geng1
1School of Resource and Environmental Sciences, Wuhan University, 299 Bayi Road, Wuhan 430072, PR China.
Nano letters
|December 26, 2023
概括
一种具有均分布的离子调节组的新型复合分离器 (HBPA-g-PE) 有效地抑制了树的生长. 这提高了金属阳极的稳定性,并使高性能硫电池成为可能.
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:
- 树的生长对金属电池的安全性和寿命构成了重大挑战.
- 控制阳极接口上的离子运输对于树突抑制至关重要.
- 分离器的设计显著影响离子分布和电池性能.
研究的目的:
- 开发一种复合分离器,以提高金属阳极的稳定性.
- 研究离子调节组对离子运输和树抑制的影响.
- 为了评估硫电池新分离器的性能.
主要方法:
- 将高分支聚胺 (HBPA) 植入聚乙烯 (PE) 上,以创建一个复合分离器 (HBPA-g-PE).
- 描述分离器上的正 (-NH2) 和负 (-CHNO-) 组的分布.
- 在高电流密度下测试Li薄膜对称电池的循环稳定性.
- 评估HBPA-g-PE在具有高硫负载和低电解质含量的硫电池中的性能.
主要成果:
- HBPA-g-PE分离器显示出密集且均分布的离子调节组.
- 薄膜对称细胞显示稳定循环超过1500小时 (3000个循环) 在20mAcm-2的低电压歇斯底里 (130mV).
- 硫电池在200多个周期中表现出稳定的性能,初始 (700 mAh g-1) 和保留 (455 mAh g-1) 容量高.
结论:
- 该HBPA-g-PE复合分离器有效调节离子运输,并抑制树突.
- 这种分离器设计促进了金属阳极的长期稳定性和高性能.
- 开发的分离器对实用,高能量密度的硫电池具有显著的前景.
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