Chloride salts/graphite foam composites prepared by vacuum impregnation with high thermal conductivity for medium temperature thermal energy storage

Chloride salts are ideal phase change materials (PCMs) for thermal energy storage (TES), but low thermal conductivity and high corrosiveness limit their applications. The use of porous skeletal materials to encapsulate chloride salts is a promising approach to overcome the above-mentioned disadvantages. In this study, graphite foam (GF) was selected as the skeleton material, low melting point LiCl-NaCl-KCl-ZnCl2 eutectic salts (LES) was selected as the PCM, and LES/GF composites were prepared by vacuum impregnation. The thermal conductivity of LES/GF reached 29.0 W/(m center dot K) at 25 degrees C, which is 68.6 times higher than LES. The highly thermally conductive 3D network structure of GF results in enhanced thermal conductivity. The thermal properties and stability of LES/GF indicate that the LES/GF composites are promising materials for medium temperature thermal storage.