论文标题
X射线计算机断层扫描和建模对锂离子电池电极的破裂预测
Cracking predictions of lithium-ion battery electrodes by X-ray computed tomography and modelling
论文作者
论文摘要
发现锂离子电极电极的断裂会导致容量褪色并降低电池的寿命。用于电池的传统断裂模型仅限于考虑单个，理想化的粒子。在这里，将高级X射线计算机断层扫描（CT）成像，电化学机械模型和相位场断裂框架组合在一起，以预测现实电池电极微结构的电极颗粒中的空隙驱动的断裂。该电极显示出表现出高度异质的电化学和断裂反应，取决于距离分离器/电流收集器的粒径和距离。该模型可以预测由于循环电压窗口扩大而增加的破裂，易感性与电极厚度的函数以及对排出速率的损害敏感性。该框架提供了一个平台，可促进对电极断裂的更深入的了解，并可以设计具有较高能力和改善降解特性的下一代电极。
Fracture of lithium-ion battery electrodes is found to contribute to capacity fade and reduce the lifespan of a battery. Traditional fracture models for batteries are restricted to consideration of a single, idealised particle; here, advanced X-ray computed tomography (CT) imaging, an electro-chemo-mechanical model and a phase field fracture framework are combined to predict the void-driven fracture in the electrode particles of a realistic battery electrode microstructure. The electrode is shown to exhibit a highly heterogeneous electrochemical and fracture response that depends on the particle size and distance from the separator/current collector. The model enables prediction of increased cracking due to enlarged cycling voltage windows, cracking susceptibility as a function of electrode thickness, and damage sensitivity to discharge rate. This framework provides a platform that facilitates a deeper understanding of electrode fracture and enables the design of next-generation electrodes with higher capacities and improved degradation characteristics.
