Cracking predictions of lithium-ion battery electrodes by X-ray computed tomography and modelling

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.

Automated summary

Fracture of lithium-ion battery electrodes can lead to capacity fade and reduced battery lifespan. Advanced imaging techniques, electro-chemo-mechanical models, and fracture frameworks have been combined to predict void-driven fracture in realistic battery electrode microstructures. The study reveals heterogeneous electrochemical and fracture responses in electrodes, influenced by particle size and distance from separator/current collector.