Below 3.7 V, the linear region on the E-√𝑡 plots shifts to 50-150 s, as demonstrated in Figure . This means that only the GITT result from the 50-150 s interval properly provides diffusion coefficients below 3.7 V. This phenomenon is also manifested by the expansion of the second semi-circle on impedance spectra (Figure ), which do not show a Warburg element within the frequency range (20 kHz-10 mHz) and thus cannot render accurate k values. The increase in charge transfer resistance represented by the enlarged semi-circle has been reported for NMC111 (LiNi0.33Mn0.33Co0.33O2) at low SoC. In summary, Figure illustrates the consistency of EIS, GITT and ICI method within their respective limitations and the importance of selecting the proper time interval where 𝑑𝐸 𝑑√𝑡 ⁄ is linear when conducting the GITT analysis.