Pd-V alloys were internally oxidized (IOed) resulting in composites of nano-particle V2O5 precipitates within Pd matrices. These composites were found to interact with H2 to form hydrogen bronzes, HxV2O5, within the Pd matrix where x can vary between 1.65 and 2.20. Relative partial molar enthalpies for H intercalation into the H-bronze within the Pd/V2O5 composite were measured calorimetrically as a function of the H content of the bronze, and these molar enthalpies decrease in magnitude from about −75 to −20 kJ/mol H as the H content increases. H2 isotherms have also been measured in disordered, fcc Pd0.96V0.04, Pd0.945V0.055, and Pd0.93V0.07 alloys from 273 K to 343 K (0 °C to 70 °C). Thermodynamic data have been derived from these isotherms. The relative partial molar enthalpies at infinite dilution of H, \(\Updelta H_{\hbox{H}}^\circ,\) increase with atom fraction V, X\(_{\hbox{V}},\) while the corresponding standard partial molar entropies, \(\Updelta \hbox{S}_{\hbox{H}}^\circ,\) decrease with \(\hbox{X}_{\hbox{V}}.\) The first-order term, g1, in a polynomial expansion of the excess or non-ideal chemical potential of H in r = H-to-metal, mol ratio, decreases in magnitude with \(\hbox{X}_{\hbox{V}}\) at a given temperature.