The electrochemical kinetics at the electrode/electrolyte interface can be revealed by the electrochemical impedance spectroscopy (EIS) analysis as seen in Fig. . The EIS exhibits similar Nyquist plot, i.e., one depressed semicircle followed by an inclined line related to Li + diffusion in the bulk electrode . The semicircle is related to the charge-transfer resistance and the intercept of the semicircle represents the internal ohmic resistance of the electrode. For the 'dry' TVP sample, the resistance is relatively high because of the poor conductivity. After the humidity treatment, there is a remarkable decrease in the charge transfer resistance, and thus an apparent reduction in battery impedance, especially for 65RH (seen in the inset of Fig. ), indicating the overall smallest resistance of charge transfer and a more-facile transfer of Li + ions at the 65RH anode/electrolyte interface. The improvement is attributed to the unique effect of the incorporated water on altering the 3D network structure of 65RH, which increases efficient channels for transportation of Li + ions and electrons.