A comparison of stitching techniques to reconstruct large volume x-ray tomography of batteries

Abstract

Synchrotron-based X-ray microtomography (μCT) is a valuable technique to study the internal structure of heterogeneous samples with high spatial and temporal resolution. However, synchrotron X-ray imaging, such as many microscopy methods, is solidly limited by its Field of View (FOV): a challenge when approaching large and/or highly detailed volumes at high spatial imaging resolution. In this study, we consider two techniques used to increase the FOV in µCT for studying Li-ion batteries, Local Tomography Stitching (LTS) and Sinogram Oriented Stitching (SOS), and compare in terms of scan time, processing efficiency and computing storage. We complement our study by estimating the impact of different battery geometries on the stitching performance for similar scanning parameters. Evaluation of the two presented techniques reveals that both provide equally satisfyingly stitched volumes. Nevertheless, it is demonstrated that SOS is predominantly more efficient for the considered battery geometries, requires fewer scans in total, and hence has a lower time and storage demand in comparison to LTS. However, technical constraints make the SOS technique more difficult to implement. Further discussed are differences in acquisition and reconstruction for the two techniques, addressing the processing efficiency for both SOS and LTS techniques and we shall provide indicators for selecting the most suitable stitching technique.