Damage and fracture can be induced not only by mechanical loading but also due to chemical interactions within a solid. On one hand, species concentration may embrittle or toughen the material and on the other hand, the mechanical state adds additional driving force for diffusion. We propose a chemo-mechanically coupled cohesive fracture model with several novel features. It distinguishes the mode-dependent damage progression and its influence on lithium transport. Coupled with mode-dependent cohesive zone damage, the model recaptures both the normal and tangential transport behavior of lithium at the interface. Moreover, it tackles concentration-dependent crack initiation, various softening behavior, as well as the cyclic damage accumulation. The thermodynamic consistency of the proposed model with the mentioned features is demonstrated. The model is numerically implemented with the finite element method. Numerical results, along with comparison with related experimental data, demonstrate that the model can be applied to study diffusion-induced fracture in general solid ionic conductors in Lithium-ion batteries. In particular, illustrative numerical results are presented for both the intergranular fracture inside active material or solid electrolyte and the interface fracture between active material and solid electrolyte. Furthermore, it is discussed how the solid electrolyte influences the dominant crack patterns. The current contribution is applicable to address similar problems on hydrogen-induced cracking and moister-dependent fracture.

损坏和断裂不仅可以由机械载荷引起，还可以由固体内的化学相互作用引起。一方面，物质浓度可能会使材料变脆或变硬，另一方面，机械状态增加了额外的扩散驱动力。我们提出了一种具有几个新特征的化学机械耦合内聚断裂模型。它区分了模式相关的损伤进展及其对锂运输的影响。再加上依赖于模式的内聚区损伤，该模型重新捕获了界面处锂的法向和切向输运行为。此外，它解决了浓度相关的裂纹萌生、各种软化行为以及循环损伤累积。证明了具有上述特征的所提出模型的热力学一致性。该模型是用有限元方法数值实现的。数值结果与相关实验数据的比较表明，该模型可用于锂离子电池中一般固体离子导体的扩散诱导断裂研究。特别是，给出了活性材料或固体电解质内部的晶间断裂和活性材料和固体电解质之间的界面断裂的说明性数值结果。此外，还讨论了固体电解质如何影响主要裂纹模式。目前的贡献适用于解决氢致开裂和潮湿相关断裂的类似问题。证明该模型可用于研究锂离子电池中一般固体离子导体的扩散诱导断裂。特别是，给出了活性材料或固体电解质内部的晶间断裂和活性材料和固体电解质之间的界面断裂的说明性数值结果。此外，还讨论了固体电解质如何影响主要裂纹模式。目前的贡献适用于解决氢致开裂和潮湿相关断裂的类似问题。证明该模型可用于研究锂离子电池中一般固体离子导体的扩散诱导断裂。特别是，给出了活性材料或固体电解质内部的晶间断裂和活性材料和固体电解质之间的界面断裂的说明性数值结果。此外，还讨论了固体电解质如何影响主要裂纹模式。目前的贡献适用于解决氢致开裂和潮湿相关断裂的类似问题。给出了活性材料或固体电解质内部的晶间断裂和活性材料和固体电解质之间的界面断裂的说明性数值结果。此外，还讨论了固体电解质如何影响主要裂纹模式。目前的贡献适用于解决氢致开裂和潮湿相关断裂的类似问题。给出了活性材料或固体电解质内部的晶间断裂和活性材料和固体电解质之间的界面断裂的说明性数值结果。此外，还讨论了固体电解质如何影响主要裂纹模式。目前的贡献适用于解决氢致开裂和潮湿相关断裂的类似问题。