Shape-stabilized lauric acid/activated carbon composites as phase change materials were prepared by adsorbing liquid lauric acid into activated carbon. In the composites, the lauric acid was used as a phase change material for thermal energy storage, and the activated carbon was used as an adsorbent that acted as the supporting material. Fourier transformation infrared spectroscope, X-ray diffractometer, scanning electronic microscope and thermal conductivity apparatus were used to determine the chemical structure, crystalloid phase, microstructure and thermal conductivity, respectively, of the composites. The thermal properties and thermal stability were investigated by a differential scanning calorimeter and a thermogravimetry analyzer. The microstructural analysis results showed that the lauric acid was well adsorbed into the porous network of the activated carbon. The thermal conductivity measurement results presented that the thermal conductivity of the composites was enhanced. The differential scanning calorimetry analysis results indicated that the composites exhibited the same phase change characteristics as those of the lauric acid and their latent heats increased with increase of the lauric acid content in composites. The thermogravimetric analysis results presented that the activated carbon can improve the thermal stability of the composites. (C) 2012 Elsevier B.V. All rights reserved.