在离子阴极LiNi0.6Mn0.2Co0.2O2单晶中成像空隙和缺陷
Isaac Martens1, Victor Vanpeene1,2, Nikita Vostrov1
1ESRF─The European Synchrotron, 71 Avenue des Martyrs, 38000 Grenoble, France.
ACS applied materials & interfaces
|December 12, 2023
概括
即使是原始的离子电池阴极材料,如NMC-622,也具有内部纳米结构. 这些缺陷,包括nanovoids和应变,影响电池性能和稳定性.
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:
- 商用离子电池阴极材料可以显示不同的性能,尽管外观相似.
- 了解内部材料结构是预测电池行为的关键.
研究的目的:
- 为了研究原始NMC-622阴极粒子的内部纳米结构.
- 为了将内部缺陷与电池的潜在性能和稳定性相关联.
主要方法:
- 扫描X射线衍射显微镜分析层间应变和晶体曲.
- 阶段对比X射线纳米断层扫描以可视化内部纳米体和粒子形态.
主要成果:
- NMC-622粒子表现出显著的内部纳米结构,包括应变梯度和结晶曲,与氧气空缺有关.
- 观察到两种粒子类型:聚合型和单晶型,突出显示异质性.
- 在许多颗粒的大部分中检测到大量的纳米体 (平均每颗颗粒12.5%).
结论:
- 内部纳米结构和缺陷,如纳米体和菌株,即使在原始的NMC-622中也存在.
- 先进的X射线技术可以量化这些缺陷,有助于预先选材料.
- 描述内部缺陷对于预测和改善离子电池性能至关重要.
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