Fig. 5: AC electrochemical impedance variations of the lithium-ion cells during cycling.
From: Data-driven capacity estimation of commercial lithium-ion batteries from voltage relaxation
The resistance increment from the initial value (Rinit) is calculated for comparison. The ohmic resistance of NCA cells (a), NCM cells (b), and NCA+NCM cells (c). SEI resistance of NCA cells (d), NCM cells (e), and NCA+NCM cells (f). Charge transfer resistance of NCA cells (g), NCM cells (h), and NCA+NCM cells (i). Only resistances before the capacity reducing to 71% of nominal capacity are shown to be consistent with the datasets in the study. The coefficient of determination (R2) between the raw and fitted impedance data is summarized in Supplementary Table 12. The SEI resistances are not identified in some cycles (seen in Supplementary Table 12) for the NCA battery (d) and NCM battery (e). The shared information of raw impedance data and fitted data can be found in the data availability.
