3D data on an 18650 Li-ion Battery Nickel-Rich NMC811 Cathode Collected using an 810 Ultra X-ray-CT instrument (Zeiss Xradia 810 Ultra, Carl Zeiss., CA, USA).Accelerating tube voltage of 35 kVp that employs a rotating chromium anode. Quasi-monochromatic beam with a characteristic emission peak of 5.4 keV (Cr-Kα). A capillary condenser produces focused X-rays for a full-field illumination of the sample, projected onto the scintillator detector using a Fresnel zone plate. In order to capture the full electrode thicknesses, two CT scans were conducted of the sample. The two Zernike phase-contrast nano-CT scans of the cathode required 1200 X-ray radiograph projections per scan, with a 30 second exposure time per projection. The raw radiographs can be made available upon request - please state 'EIL-011.tif' and 'EIL-012.tif'. The two nano-CT datasets were then reconstructed using commercial software employing parallel-beam filtered back-projection algorithms (‘Reconstructor Scout-and-Scan’, Carl Zeiss., CA, U.S.A.),producing an isotropic voxel length of 63.1 nm. The reconstructed volumes were then stitched using Avizo Fire software (Avizo, Thermo Fisher Scientific, Waltham, Massachusetts, U.S.A.) producing one nano-CT tomogram (EIL-014.tif).