Summary X-ray computed tomography (CT) is widely used for nondestructive inspection of cylindrical lithium-ion batteries. However, in conventional flat-detector-based CT systems, spatial resolution is limited by focal-spot-induced blurring, which becomes severe at the cell periphery due to an increased object-to-detector distance. This is particularly problematic for cylindrical battery inspection, where resolving peripheral features such as electrode termination positions is essential. Here, we present a curved-scintillator-based optically coupled X-ray CT system that reduces the effective object-to-detector distance at the periphery, suppressing focal-spot-induced blurring while enabling the use of a high-power X-ray tube. The system is experimentally demonstrated through CT imaging of a 4680 cylindrical lithium-ion cell. The curved scintillator improves peripheral spatial resolution by approximately 8% compared with the flat-scintillator configuration, providing more uniform resolution across the field of view. Frequency- and image-domain resolution analyses confirm the improvement, indicating the potential of the curved-scintillator-based system for high-resolution inspection of cylindrical lithium-ion batteries.
Im et al. (Mon,) studied this question.