Cohesive modeling of crack nucleation under diffusion induced stresses in a thin strip: Implications on the critical size for flaw tolerant battery electrodes

Recent advances in lithium-ion battery electrodes with huge volume changes during intercalation-deintercalation cycles are calling for studies on crack nucleation under diffusion induced stresses. Here we develop a cohesive model of crack nucleation in an initially crack-free strip electrode under galvanostatic intercalation and deintercalation processes. The analysis identifies a critical characteristic dimension below which crack nucleation becomes impossible. The critical size and other predictions of the model are compared to recent experiments on silicon nanowire electrodes. The results suggest nanostructured electrodes are highly promising for applications in high capacity batteries. (C) 2010 Elsevier Ltd. All rights reserved.