Nomura Yuki, Yamamoto Kazuo, Fujii Mikiya, Hirayama Tsukasa, Igaki Emiko, Saitoh Koh
Technology Innovation Division, Panasonic Corporation, 3-1-1 Yagumo-naka-machi, Moriguchi, Osaka, 570-8501, Japan.
Nanostructures Research Laboratory, Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atsuta, Nagoya, Aichi, 456-8587, Japan.
Nat Commun. 2020 Jun 4;11(1):2824. doi: 10.1038/s41467-020-16622-w.
Lithium-ion transport in cathodes, anodes, solid electrolytes, and through their interfaces plays a crucial role in the electrochemical performance of solid-state lithium-ion batteries. Direct visualization of the lithium-ion dynamics at the nanoscale provides valuable insight for understanding the fundamental ion behaviour in batteries. Here, we report the dynamic changes of lithium-ion movement in a solid-state battery under charge and discharge reactions by time-resolved operando electron energy-loss spectroscopy with scanning transmission electron microscopy. Applying image denoising and super-resolution via sparse coding drastically improves the temporal and spatial resolution of lithium imaging. Dynamic observation reveals that the lithium ions in the lithium cobaltite cathode are complicatedly extracted with diffusion through the lithium cobaltite domain boundaries during charging. Even in the open-circuit state, they move inside the cathode. Operando electron energy-loss spectroscopy with sparse coding is a promising combination to visualize the ion dynamics and clarify the fundamentals of solid-state electrochemistry.
锂离子在阴极、阳极、固体电解质及其界面中的传输，对固态锂离子电池的电化学性能起着至关重要的作用。在纳米尺度上直接观察锂离子动力学，为理解电池中基本离子行为提供了有价值的见解。在此，我们通过时间分辨的扫描透射电子显微镜原位电子能量损失谱，报告了固态电池在充放电反应过程中锂离子迁移的动态变化。通过稀疏编码进行图像去噪和超分辨率处理，极大地提高了锂成像的时间和空间分辨率。动态观察表明，在充电过程中，钴酸锂阴极中的锂离子通过钴酸锂畴界扩散而复杂地脱出。即使在开路状态下，它们也在阴极内部移动。结合稀疏编码的原位电子能量损失谱，是一种很有前景的组合，可用于可视化离子动力学并阐明固态电化学的基本原理。
