where v is scan rate, both k1 and k2 are parameters. In Fig. , the fraction of charge stored arising from capacitive processes of 65RH sample is determined to be 51 % at a scan rate of 0.1 mV s -1 . As the scan rate increases to 0.2, 0.5, 1 and 2 mV s -1 , the capacitive contributions are 59%, 68%, 64.8%, 75%, and 83%, respectively (Fig. ), suggesting the capacitive-dominant characteristics at high-rate conditions. This phenomenon could be ascribed to the nanocrystals induced by the incorporated water with a large surface area, which provides extra active sites for lithiation/delithiation through the capacitive process. Such a prominent contribution by capacitive lithium storage not only gives 65RH a superior high-rate capability, but also improves its cycling stability and high rates capability. To clarify the reasons for the booming capacities of the hydrous samples, XPS was employed to probe the chemical states of the components, especially the OH species, in the four sample before cycles. The O 1s high-resolution XPS spectra of the four samples are displayed in Fig. , where the broad and asymmetric peak of each sample can be deconvoluted into three peaks, revealing the presence of at least three distinct oxygen species. Notably, the peak at 533.1 eV is associated with the crystal water in the precipitated H4V3P3O16.5⋅xH2O, i.e., the molecularly adsorbed H2O . The peak at 531.5 eV corresponds to the -OH groups . It is evident that the areas of the two peaks in the hydrated samples expand dramatically with increasing relative humidity, suggesting that more H2O and -OH groups reside in the samples. This result is consistent with the observation on TGA, i.e., the structural H2O including the OH species could be incorporated into the network structure of glass matrix. Thus, it is reasonable to infer that the incorporated H2O might contribute greatly to the boosted capacity of TVP glass after the hydration treatment. A g -1 , respectively. It is seen that the Bragg peaks in the XRD pattern of the 65RH and 85RH disappeared, instead, a hump was observed in the patterns of the samples after cycles. This means that the nanocrystals induced by humidity treatment were transformed into amorphous domain, i.e., experienced an order-disorder transition, during discharge/charge cycles.