Assessing rechargeable batteries with 3D X-ray microscopy, computed tomography, and nanotomography

In the last three decades, significant advances have been made in rechargeable battery technologies. However, battery cell manufacturers still face quality and process control challenges when attempting to non-destructively map the microstructure of battery electrodes, their inhomogeneities, and their effect on battery ageing and performance degradation. This paper introduces workflows that combine computed tomography and 3D X-ray microscopy to generate a detailed three-dimensional visualisation of the interior of battery cells and assemblies, without destroying them, to enable the study of their internal structure before and after charging/discharging cycles. These imaging workflows can be run independently or complementary to other multiscale correlative microscopy evaluations and provide valuable insights into the inner workings of battery systems at multiple length scales, from macroscopic features on battery packs (i.e. hundreds of mm) to microscopic details in electrode materials (in the tens of nm). Understanding battery systems through X-ray imaging can speed development time, increase cost efficiency, and simplify failure analysis and quality inspection of lithium-ion batteries and other cells built with emerging new energy materials.