(Invited) A Macro-to-Nano Zoom through the Hierarchy of a Lithium Ion Battery

Abstract

Lithium-ion battery (LIB) is featured by structural and chemical complexities across a broad range of length scales and, ultimately, it is the hierarchy of the battery structure that determines its functionality. The study of the battery function, degradation, and failure mechanisms requires a thorough and systematic investigation from the structural, chemical, mechanical, and dynamic perspectives. X-ray-based characterization techniques are playing an important role in this research field.In this talk, I will review my group’s research activities over the past few years [1-10] by presenting a macro-to-nano zoom through the hierarchy of a standard battery cell [2] using a suite of state-of-the-art X-ray techniques. Damage [6-7], deformation, compositional [9-10] and chemical [1, 4-5] heterogeneity at different length scales are visualized and are associated to different degradation phenomena and mechanisms. Our results highlight the importance of the battery cathode material’s mechanical properties [7-8], which evolve upon battery cycling and could significantly impact both the immediate and the long-term cell behaviours. Statistical analysis, numerical modelling [4], and machine learning [3, 5-6] approaches are key components integrated in our research efforts and will be touched upon in this presentation. I hope this presentation will ignite enthusiasm and ideas for future collaborations.