Fig. 4.

Electrochemical impedance spectroscopy analysis after ten discharge–charge cycles. a, b Temperature-dependent Nyquist plots of the TiO₂ anode for the EC/DEC-based electrolyte (a) and the diglyme-based electrolyte (b). c Arrhenius plot of the resistance contributions of the solid electrolyte interphase R_SEI and the charge transfer resistance R_ct, with the derived activation energies E_a,SEI and E_a,ct for the TiO₂ anode in the two electrolytes. d Comparison of the charge transfer energy barriers in the diglyme-based electrolyte and EC/DEC-based electrolytes for various electrode materials