fig5

Figure 5. (A) EIS results at 50% SOC and the corresponding equivalent circuit model (inset: linear fitting of Z_Re to ω^-0.5 in the frequency range of 0.01-0.1 Hz). (B) Charge transfer resistance (R_ct) at various SOC. (C) Solid-phase Li-ion diffusion coefficient ($$ D_{\mathrm{Li}}{ }^{+} $$) at various SOC. (D) Voltage-capacity curves at 15C charge/discharge and the schematic illustration for calculating overpotential during charge (η_ch) and discharge (η_dis). (E) Tafel plot and the linear fitting in large overpotential regions. (F) Calculated exchange current density (j₀) during charge and discharge.