Linking void and interphase evolution to electrochemistry in solid-state batteries using operando X-ray tomography
Linking void and interphase evolution to electrochemistry in solid-state batteries using operando X-ray tomography
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DOI：
10.1038/s41563-020-00903-2
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发表时间：
2021-01-28
期刊：
影响因子：
41.2
通讯作者：
McDowell, Matthew T.
中科院分区：
文献类型：
--
作者：
Lewis, John A.;Cortes, Francisco Javier Quintero;McDowell, Matthew T.
尽管固态电池工程取得了进展，但与固液界面相比，我们对控制固固界面电化学行为和稳定性的化学机械现象的理解仍然有限。在这里，我们使用操作同步加速器 X 射线计算机显微断层扫描来研究电池循环过程中锂/固态电解质界面的演变，揭示空隙形成、相间生长和体积变化之间复杂的相互作用如何决定电池行为。在对称电池中可以直接观察到锂剥离过程中形成的空隙，并且对驱动锂和固态电解质 (Li10SnP2S12) 之间界面处的电流收缩的接触损失进行了量化，发现这是电池故障的主要原因。发现界面在充电时具有氧化还原活性，并且由于任一电极处的部分摩尔体积不匹配而发生整体体积变化。这些结果让我们深入了解化学机械现象如何影响电池性能，从而促进固态电池的发展。
Despite progress in solid-state battery engineering, our understanding of the chemo-mechanical phenomena that govern electrochemical behaviour and stability at solid-solid interfaces remains limited compared to at solid-liquid interfaces. Here, we use operando synchrotron X-ray computed microtomography to investigate the evolution of lithium/solid-state electrolyte interfaces during battery cycling, revealing how the complex interplay among void formation, interphase growth and volumetric changes determines cell behaviour. Void formation during lithium stripping is directly visualized in symmetric cells, and the loss of contact that drives current constriction at the interface between lithium and the solid-state electrolyte (Li10SnP2S12) is quantified and found to be the primary cause of cell failure. The interphase is found to be redox-active upon charge, and global volume changes occur owing to partial molar volume mismatches at either electrode. These results provide insight into how chemo-mechanical phenomena can affect cell performance, thus facilitating the development of solid-state batteries.