The effect of expanded graphite (EG) size on thermal performances of PCM has been little discussed although many EG-based PCMs were investigated. Here, three different sizes of EGs (50, 80, 100 mesh) were adopted as supporting materials to prepare their respective composite PCMs (CPCMs). Form-stability, thermal conductivity and phase change behavior of CPCM were systematically discussed. Results indicated that the shape-stabilized effect and the adsorptive rate of EG-50 for modified CaCl₂·6H₂O PCM were superior to that of EG-80 and EG-100, which originated from its larger proportions of micropores, larger specific area and pore volume respectively. The results of pore structure analysis and SEM confirmed that the pore structures of three kinds of EGs were occupied by modified CaCl₂·6H₂O PCM. CPCM with EG-50 possessed a higher thermal conductivity and latent heat than that of the other two with EG-80 and EG-100 respectively, which were due to the low interfacial thermal resistance and the small confinement effects in EG-50 respectively. The addition of EG could suppress the supercooling degree of modified CaCl₂·6H₂O PCM. This work will provide insights into the enhanced thermal performance for shape-stabilized CPCMs by introducing carbon-based supporting materials with appropriate size.

尽管已经研究了许多基于EG的PCM，但很少讨论膨胀石墨（EG）尺寸对PCM热性能的影响。在这里，采用三种不同尺寸的EG（50、80、100目）作为支撑材料，以准备它们各自的复合PCM（CPCM）。系统地讨论了CPCM的形状稳定性，导热性和相变行为。结果表明，EG-50对CaCl ₂ ·6H ₂ O PCM的形状稳定作用和吸附速率优于EG-80和EG-100，这是由于其微孔比例较大，比表面积较大所致。和孔体积。孔结构分析和SEM结果表明，改性的CaCl占据了三种EG的孔结构。₂ ·6H ₂ O PCM。EG-50的CPCM的导热系数和潜热分别高于其他两种EG-80和EG-100的导热系数和潜热，这分别是由于EG-50的界面热阻低和限制作用小。EG的加入可以抑制改性CaCl ₂ ·6H ₂ O PCM的过冷度。通过引入适当尺寸的碳基支撑材料，这项工作将为形状稳定的CPCM增强的热性能提供见解。