相关的双梯度电极使高质量负载Li-S电池在高电流密度下实现空间同步的硫氧化还原
Yuxuan Zhang1, Yeongjun Oh1, Jinwook Baek1
1School of Engineering Technology, Purdue University, West Lafayette, Indiana, USA.
Advanced materials (Deerfield Beach, Fla.)
|December 26, 2025
概括
一个新的双梯度电极设计克服了硫 (Li-S) 电池的局限性,改善了用于高功率应用的离子传输和氧化还原动力学. 这一策略提高了Li-S电池的性能和能量密度.
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:
- -S电池的实际部署受到缓慢的氧化还原动力学和高质量负载硫阴极中的劣质离子传输的限制,特别是在快充条件下.
- 使用电催化剂的现有策略仅部分解决了电化学极化,无法解决厚电极中的度和欧姆极化.
研究的目的:
- 开发一种高性能Li-S电池的合材料架构方法.
- 为了克服缓慢的氧化还原动力学和厚硫阴极中较差的离子运输的局限性.
主要方法:
- 使用立体石刻和热解,制造一种低曲率,相关的双梯度电极.
- 将电催化剂 (Fe2O3/Fe-N-C) 与Li2S纳米粒子集成到一个层次结构中.
- 微观孔径梯度与活性物质梯度的相关性,以同步氧化还原进展.
主要成果:
- 双梯度电极实现了高面积容量 (22.7 mAh cm−2 在0.1 C,15.7 mAh cm−2 在5 C).
- 证明了卓越的循环稳定性,在4C时在1100个循环中保持82%的容量.
- 一个袋式电池达到403Wh kg-1的特定能量,展示了高能量和高功率的能力.
结论:
- 集成的双梯度策略有效地使阴极利用同质化,并减轻极化问题.
- 层次结构和嵌入式电催化剂提高了离子可访问性和聚硫化物转化.
- 这种方法显示出对推进现实世界高能和高功率Li-S电池技术的重大前景.
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