Charge distribution guided by grain crystallographic orientations in polycrystalline battery materials
Charge distribution guided by grain crystallographic orientations in polycrystalline battery materials
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DOI：
10.1038/s41467-019-13884-x
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发表时间：
2020-01-08
影响因子：
16.6
通讯作者：
Lin, Feng
中科院分区：
文献类型：
--
作者：
Xu, Zhengrui;Jiang, Zhisen;Lin, Feng
构建晶粒晶体取向可以调节电荷分布和化学机械性质，以增强多晶电池材料的性能。然而，探索电荷分布，晶粒晶体取向和性能之间的相互作用仍然是一个艰巨的挑战。在此，我们阐明了空间分辨的电荷分布在锂层状氧化物与不同的晶粒晶体结构的安排，并建立了一个模型来量化它们的电荷分布。虽然整体的“表面到体”的电荷分布在多晶颗粒中占主导地位，但晶体取向引导的氧化还原反应控制着局部带电纳米畴中的电荷分布。与随机取向的晶粒相比，径向排列的晶粒在电池循环时表现出较低的电池极化和较高的容量保持率。径向排列的晶粒产生较少曲折的锂离子路径，从而改善电荷均匀性，如从多晶颗粒中超过2000万个纳米畴统计量化的。这项研究提供了一个更好的理解多晶电池材料的电荷分布和化学机械性能。
Architecting grain crystallographic orientation can modulate charge distribution and chemomechanical properties for enhancing the performance of polycrystalline battery materials. However, probing the interplay between charge distribution, grain crystallographic orientation, and performance remains a daunting challenge. Herein, we elucidate the spatially resolved charge distribution in lithium layered oxides with different grain crystallographic arrangements and establish a model to quantify their charge distributions. While the holistic "surface-to-bulk" charge distribution prevails in polycrystalline particles, the crystallographic orientation-guided redox reaction governs the charge distribution in the local charged nanodomains. Compared to the randomly oriented grains, the radially aligned grains exhibit a lower cell polarization and higher capacity retention upon battery cycling. The radially aligned grains create less tortuous lithium ion pathways, thus improving the charge homogeneity as statistically quantified from over 20 million nanodomains in polycrystalline particles. This study provides an improved understanding of the charge distribution and chemomechanical properties of polycrystalline battery materials.