Dynamic Lithium Transport Pathway via Crack Formation in Phase-Separating Battery Particles

High Resolution Image Download MS PowerPoint Slide Nanoscale cracks within battery particles are ubiquitously induced during battery cycling. Tracking the origin of nanocrack formation and its subsequent propagation remains challenging, although it is crucial for the cycle life and kinetics of batteries. Moreover, it is even more challenging to understand how such nanocracks influence lithium (de)insertion pathways and local strain fields within battery particles. In this study, we utilized operando scanning transmission X-ray microscopy on individual LiFePO 4 (LFP) particles to visualize the relationship between lithium (de)insertion pathways and crack formation and propagation. We first demonstrate the generation mechanism of nanocracks occurs when the lithium insertion pathway at the edge of fresh LFP particles induces strong tensile stress in the middle of the particle. Then, we dire…