Polymorphism of garnet solid electrolytes and its implications for grain-level chemo-mechanics
Polymorphism of garnet solid electrolytes and its implications for grain-level chemo-mechanics
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DOI：
10.1038/s41563-022-01333-y
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发表时间：
2022-09-01
期刊：
影响因子：
41.2
通讯作者：
Hatzell, Kelsey B.
中科院分区：
文献类型：
--
作者：
Dixit, Marm B.;Vishugopi, Bairav S.;Hatzell, Kelsey B.
了解和减轻灯丝形成、短路和固体电解质断裂对于先进的全固态电池是必要的。在这里，我们采用了耦合的远场高能衍射显微镜和断层扫描的方法来评估致密，多晶石榴石（Li 7 La 3 Zr 2 O 12）固体电解质的化学机械行为与晶粒级分辨率。现场监测的颗粒级应力响应表明，故障机制是随机的，并受局部微观结构的异质性。耦合高能X射线衍射和远场高能衍射显微镜测量揭示了存在的相异质性，可以改变局部化学力学内的散装固体电解质。这些局部区域被提议为具有LLZO的立方多晶型物的存在的区域，可能由局部掺杂剂浓度变化引起。耦合层析成像和FF-HEDM实验相结合的传输和力学建模来说明多晶石榴石固体电解质的降解。研究结果展示了高性能固态电池的加工途径。了解和减轻灯丝形成、短路和固体电解质断裂对于先进的全固态电池是必要的。本文研究了多晶型对致密多晶石榴石固体电解质晶粒化学机械行为的影响。
Understanding and mitigating filament formation, short-circuit and solid electrolyte fracture is necessary for advanced all-solid-state batteries. Here, we employ a coupled far-field high-energy diffraction microscopy and tomography approach for assessing the chemo-mechanical behaviour for dense, polycrystalline garnet (Li7La3Zr2O12) solid electrolytes with grain-level resolution. In situ monitoring of grain-level stress responses reveals that the failure mechanism is stochastic and affected by local microstructural heterogeneity. Coupling high-energy X-ray diffraction and far-field high-energy diffraction microscopy measurements reveals the presence of phase heterogeneity that can alter local chemo-mechanics within the bulk solid electrolyte. These local regions are proposed to be regions with the presence of a cubic polymorph of LLZO, potentially arising from local dopant concentration variation. The coupled tomography and FF-HEDM experiments are combined with transport and mechanics modelling to illustrate the degradation of polycrystalline garnet solid electrolytes. The results showcase the pathways for processing high-performing solid-state batteries.Understanding and mitigating filament formation, short-circuit and solid electrolyte fracture is necessary for advanced all-solid-state batteries. The effect of polymorphism on the grain-level chemo-mechanical behaviour of dense and polycrystalline garnet solid electrolytes is now investigated.