Thermo-mechanical properties of compaction molded cement-based composite containing a high mass fraction of phase change material for thermal energy storage

This study presents a novel compaction molded composite of sulphoaluminate cement-based thermal energy storage mortar (SCTESM) containing shape stabilized phase change materials (SSPCM) up to 25.9 wt%. A series of tests were conducted to investigate the thermo-mechanical properties of SCTESM. The results show that the thermal conductivity of the compaction molded SCTESM is about 60% higher than that of casting molded one. A mathematical model for thermal conductivity prediction was proposed with a maximum relative error of 5.69%. Furthermore, the thermal penetration depth of SCTESMs was also analyzed, and the thermal penetration depth of the compaction molded samples was over 30% higher than that of casting molded sample of same SSPCM dosage. The mechanical strength determination revealed that compaction molding method can increase the 28-day compressive strength and flexural strength of SCTESM by 28.0% and 40.0% than that of casting molded one with the same SSPCM dosage.