由一个晶体化合物为快速的Li-S化学提供动力的Li+移动性
Ben Chen1, Boxin Li1, Jingxuan Bi1
1Frontiers Science Center for Flexible Electronics & Shaanxi Institute of Flexible Electronics, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China. iamhfdu@nwpu.edu.cn.
概括
研究人员开发了一种新型的碳复合材料 (LiPN2@C) 来改进硫 (Li-S) 电池. 这种材料抑制了聚硫化物穿,并增强了离子运输,提高了电池的性能和寿命.
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:
- 聚硫化物的穿效应阻碍了硫 (Li-S) 电池的性能.
- 阻断层可以抑制这种效应,但通常会阻碍离子运输.
研究的目的:
- 开发一种材料,同时减轻聚硫化物运输,并促进Li-S电池中的Li+运输.
- 为了提高电化学性能和Li-S电池的循环寿命.
主要方法:
- 通过 Li+ 吸收的胺聚酸盐的一步化合成了以为基础的,与碳 (LiPN2@C) 复合的晶体.
- 用LiPN2@C材料修改了一个分离器.
- 研究了使用修改过的分离器的Li2S阴极的电化学性能.
主要成果:
- 这种LiPN2@C材料有效地抑制了聚硫化物的转运,并改善了Li+的运输.
- 2S阴极显示了较低的激活电位 (2.4V) 和高速率容量 (519mAhg-1在2C).
- 电池在0.5°C下达到726mAhg-1的容量,衰变率低 (每100个循环周期的衰变率为0.25%).
结论:
- LiPN2@C复合材料是提高Li-S电池性能的一个有希望的材料.
- 同时抑制聚硫化物穿和促进Li+运输对于先进的Li-S电池设计至关重要.
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