In case study 2, operando micro-CT of NMC811 at multiple SOC was acquired at the DLS i13-2 beamline . A bespoke pouch cell sample holder made of Polyether Ether Ketone (PEEK) with an aluminium x-ray window compressed the pouch cell throughout the experiment. This allowed the same ROI to be scanned repeatedly without removing the cell between scans. The ROI was a tab that had been laser cut from the electrode so that it extended above the rest of the pouch cell, which is shown in figure .2. Electrical connections allowed for electrochemical control of the cell for charge/discharge between specific voltages (vs. Li/Li+). The ROI was first scanned in the pristine state, and then after being charged and held at; (charging) 4.0 V, 4.1 V. 4.2 V, 4.3 V, 4.4 V, and (discharging) 4.3 V, 4.2 V, 4.1 V, 4.0 V, 3.8 V, & 2.5 V. However, in this paper, the data analysed is limited to tomograms acquired at pristine, 4.0 V, 4.4 V, and 2.5 V after discharge. Scanning was performed at open circuit voltage, after a voltage hold until current had dropped to 10% of the charging current. A pco.edge 5.5 scintillator-coupled detector with a 10 × objective lens was used which resulted in an effective pixel size of 325 nm. The FoV was 0.83 × 0.70 mm. For each tomography scan, 3000 projections were acquired between 0-180 • with 0.8 seconds exposure. The 'pink beam', which makes use of multiple harmonics from the undulator, was utilised, resulting in higher flux than the monochromatic beam. The beam had an average energy of ∼ 27 keV.