The potentials for various Pd-Li alloys in coexisting phase states were investigated in LiCl-KCl eutectic melt in the temperature range of 673-773 K. The activities and the relative partial molar Gibbs free energies of Li were calculated from the measured potentials for various Pd-Li alloy phases, i.e., Pd7Li, Pd2Li, PdLi, PdLi2, and the liquid phase. The relative partial molar entropies and enthalpies of Li were also calculated for the Pd-Li alloys by using the temperature dependence of the potentials. Using the Gibbs-Duhem relation, the activities and the relative partial molar properties of Pd were calculated from the activities of Li for the Pd-Li alloy phases. Finally, the standard Gibbs free energies of formation were calculated for the Pd-Li alloy phases.