Shape-stabilized phase change materials for thermal energy storage and heat dissipation

Abstract

Shape-stabilized phase change material (SSPCM) are widely used as energy storage materials due to its advantages of easy preparation and adjustable scale. But the thermal conductivity enhancement of SSPCM still need to be further studied to improve the energy storage efficiency. In this work, silicone rubber (SR)/paraffin@SiO2 (Pn@SiO2)/graphene nanoplates (GNPs) shape-stabilized phase change materials (SPG) with different GNPs content were prepared. Pn@SiO2 and GNPs can be homogeneously dispersed in the SR matrix due to the enhanced interfacial compatibility between Pn@SiO2 and SR. The leakage rate of SPG composites was as low as 0.25% due to the protection of SiO2 shell, SR matrix and GNPs. The SPG composites had excellent thermal storage properties, with the enthalpy about 50 J·g−1. The thermal conductivity of SPG composites was improved with the content of GNPs, the thermal conductivity of SPG reach 0.989 W·m−1·K−1 at a GNPs content of 10 phr. The low hardness of SPG composites above the phase change temperature can provide a more cohesive surface when applied to heat dissipation. The heat dissipation of the SPG composites in electric devices was simulated and demonstrated that the addition of GNPs made the heat dissipation rate of the SPG composites increased significantly. Therefore, the SPG composites can be applied in thermal energy storage and heat dissipation of electronic devices.