Polyethylene oxide (PEO)/Li x MoO 3 nanocomposites were prepared by the direct melt method. Characterization of the nanocomposites using thermal gravimetric analysis, differential scanning calorimetry, and powder X-ray diffraction shows that polymer chains intercalate inorganic host lamella and exhibit a lattice expansion along the stacking direction of 7.7 9, consistent with the lattice expansion of nanocomposites prepared by the solution method. The intercalation of the polymer chains in Li x MoO 3 galleries suppresses their tendency to crystallize.