The other quantity experimentally determined in these methods used in the calculation of the diffusion coefficient (Equations 16 and 19) is the OCP slope. Figure presents a comparison between the slopes of the OCP obtained from the relaxed potential at the end of the rest period in the GITT protocol and the iR-corrected pseudo-OCP in the ICI analysis. The difference between the values from two methods are minimal above 3.65 V. The deviation at low SoC is presumably linked to the high resistance discussed above, which interferes with the resistance determination of the ICI method. Nevertheless, the good agreement between the slopes of OCP and iR-corrected pseudo-OCP in most SoC intervals indicates that the ICI method alone can deliver the required electrochemical parameters for the calculation of the diffusion coefficient above 3.7 V. By skipping the time-consuming relaxation periods, the ICI method can save around 90% of the time spent on common GITT protocols, such as the one used in this work. + derived from the GITT with data selection interval 5-40 s and 50-150 s, the ICI method and the EIS fitting (𝑘 = 𝜎$8/𝜋, σ: Warburg coefficient). The maximum of the y-axis is set to 30 Ω s -0.5 to show the differences of the data above 3.7 V. Due to a technical issue, the spectra below 3.8 V in the first charge were not properly collected, but it was solved afterwards.