An Analysis of Solid-State Electrodeposition-Induced Metal Plastic Flow and Predictions of Stress States in Solid Ionic Conductor Defects
An Analysis of Solid-State Electrodeposition-Induced Metal Plastic Flow and Predictions of Stress States in Solid Ionic Conductor Defects
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DOI：
10.1149/1945-7111/ab6c5b
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发表时间：
2020-01-29
影响因子：
3.9
通讯作者：
Ceder, Gerbrand
中科院分区：
文献类型：
--
作者：
Barroso-Luque, Luis;Tu, Qingsong;Ceder, Gerbrand
已经提出使用具有金属电极的无机固体离子导体作为增加能量密度、降低容量损失和防止金属传播引起的故障的方式。目前对固态系统中锂金属电极引起电池短路的观察已被确定为限制该技术发展的主要障碍。然而，所涉现象的许多方面在理论上尚未得到充分解决。在这项工作中，我们推导出一个数学模型的电沉积诱导塑性流动的金属/无机固体导体系统。我们使用一个半解析的解决方案，以获得在金属突起的压力增加的表达式，并评估断裂的可能性。结果给出了类似于层流槽道流动的流动解。该解决方案还显示了如何考虑到边界牵引电位从建立的压力，导致离子再分布，并有效地筛选孤立的缺陷，使局部电流集中观察到的电解质断裂的不完整的解释。我们表明，边界牵引潜力设置一个最大值的压力增加，可以发生沉积在一个孤立的缺陷。我们推导出断裂可能发生的条件，并量化了离子电导率和电解质断裂韧性在扩展金属电极固态电解质的安全操作制度中的作用。(C)2020作者（S）由IOP Publishing Limited代表电化学学会出版。
The use of inorganic solid-ionic conductors with a metal electrode, has been proposed as a way to increase energy density, decrease capacity loss and prevent failure from metal propagation. Current observations of Li-metal electrodes causing cell shorting in solid-state systems have been identified as main obstacles limiting the development of this technology. However, many aspects of the involved phenomenon have not been fully addressed theoretically. In this work, we derive a mathematical model of electrodeposition-induced plastic flow in metal/inorganic solid-conductor systems. We use a semi-analytical solution to derive pressure increase expressions at metal protrusions and assess the possibility of fracture. The results give flow solutions analogous to laminar channel flow. The solutions also show how taking into account a boundary traction potential from built up pressure, leads to ionic redistribution and effectively screens isolated flaws, making local current focusing an incomplete explanation for observed electrolyte fracture. We show that the boundary traction potential sets a maximum value for the pressure increase that can occur from deposition at an isolated flaw. We derive conditions under which fracture can occur, and quantify the role of ionic conductivity and electrolyte fracture toughness in extending safe operating regimes of solid-state electrolytes with metal electrodes. (C) 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited.