丰富层氧化物的阴极-电解质间相:结构的演变和对稳定性的影响
Menghao Li1,2, Xuming Yang3, Xianbin Wei1,2
1Eastern Institute for Advanced Study, Eastern Institute of Technology, Ningbo, Zhejiang 315200, P. R. China.
Nano letters
|February 11, 2025
概括
这项研究揭示了使用冷TEM的阴极电解质介面 (CEI) 的原子级细节. 了解CEI结构是提高电池性能和寿命的关键.
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
- 纳米技术 纳米技术
背景情况:
- 阴极-电解质介面 (CEI) 对于电池性能至关重要,但其结构和功能尚不清楚.
- 现有的CEI知识是有限的,经常受到争论,阻碍了电池的发展.
研究的目的:
- 使用低温传输电子显微镜 (cryo-TEM) 可视化原子分辨率CEI结构.
- 调查电池循环期间CEI的动态演变.
- 为了将CEI结构与电池性能相关联.
主要方法:
- 利用冷传输电子显微镜 (cryo-TEM) 进行原子分辨率成像.
- 使用富含氧化物 (LiNi0.8Co0.1Mn0.1O2,NCM811) 微粒作为模型阴极.
- 分析了基于乙烯碳酸盐 (EC) 和乙烯碳酸盐 (FEC) 的电解质中CEI的形成和演变.
主要成果:
- 获得了前所未有的CEI结构的高分辨率图像.
- 观察到不同的CEI构成:EC电解质中的无形有机丰富层和FEC电解质中的富含LiF的颗粒.
- 记录了CEI加厚和不同结构演变 (马赛克与双层) 与循环.
结论:
- 化TEM有效地揭示了原子分辨率CEI结构.
- CEI结构随着循环而动态演变,并根据电解质组成而有所不同.
- 这项研究为CEI动态提供了关键的见解,解决了争议并指导了未来的电池设计.
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