Preparation of a novel microencapsulated phase change material (MEPCM)/adipic acid ceramic composite and its thermal performance

Metal-based phase change materials (PCM) have received extensive attention due to their high thermal conductivity and high volumetric heat storage density. However, their relatively low heat storage density per unit mass and leakage have limited their applications. Herein, a porous ceramic was firstly prepared using SnBi58 MEPCM (Tm = 140.8 °C) with thermal expansion void and ceramic materials as framework materials, and PMMA as pore-forming agent. Then, MEPCM/adipic acid ceramic composite was fabricated by impregnating adipic acid (Tm = 157.3 °C) with high latent heat per unit mass into the porous ceramic. The results showed that the MEPCM/adipic acid ceramic composite with 35 wt% MEPCM addition exhibited the best performance taking into account thermal conductivity and latent heat. The latent heat was 92.73 J/g, and the thermal conductivity of the composite was 2.183 W/(m·K), increased by nearly 3 times compared to pure adipic acid (0.513 W/(m·K)) and increased by 97.4% compared to the ceramic composite without MEPCM (1.1058 W/(m·K)). Furthermore, due to the presence of void in MEPCM, MEPCM/adipic acid ceramic composite exhibited good thermal cycling stability. The MEPCM/adipic acid ceramic composite with high thermal conductivity, high latent heat and high thermal reliability exhibits good applications prospects in the next generation of heat storage.