Intact, Commercial Lithium-Polymer Batteries: Spatially Resolved Grating-Based Interferometry Imaging, Bragg Edge Imaging, and Neutron Diffraction

Abstract

We survey several neutron imaging and diffraction methods for non-destructive testing and evaluation of intact, commercial lithium-ion batteries. Specifically, far-field interferometry was explored as an option to probe a wide range of autocorrelation lengths within the batteries via neutron imaging. The dark-field interferometry images change remarkably from fresh to worn batteries, and from charged to discharged batteries. When attempting to search for visual evidence of battery degradation, neutron Talbot-Lau grating interferometry exposed battery layering and particle scattering through dark-field imaging. Bragg edge imaging also reveals battery wear and state of charge. Neutron diffraction observed chemical changes between fresh and worn, charged and discharged batteries. However, the utility of these methods, for commercial batteries, is dependent upon battery size and shape, with 19 to 43 mAh prismatic batteries proving most convenient for these experimental methods. This study reports some of the first spatially resolved, small angle scattering (dark-field) images showing battery degradation.

Data-driven simulations for training AI-based segmentation of neutron images

“…NIST has been working on a prototype instrument that is capable of measuring this range of scales. The applications of multi-scale hierarchical characterization by INFER are wide-ranging, for example, measuring samples of civil engineering structures (e.g., cement 8 ), polymers 9 , additive manufacturing 10 , 11 , steels 12 and magnetic domains 13 , chemistry of complex systems (e.g., batteries 14 , 15 and fuel cells 16 , 17 ), and complex hierarchical structures (e.g., wood 18 and bones 19 ) as well as in geology 20 and food science 21 .…”