Nano-enhanced PCMs for low-temperature thermal energy storage systems and passive conditioning applications

Phase change material (PCM)-based thermal energy storage (TES) systems are preferred due to high energy density; however, they possess an inherent problem of low dispatchability. This is due to the low thermal conductivity of the constituent PCMs. For ensuring high energy density and high rate of dispatchability of the TES systems, it is necessary to find methods to enhance the thermal conductivity of these PCMs. The present study chooses low-temperature melting PCM (n-nonadecane) which is suitable for thermal regulation of various devices, systems and buildings. For enhancement of PCM, TiO2 nanoparticles are prepared using continuous spray pyrolysis method and dispersed within the PCM matrix using advanced wet impregnation technique, to form nano-enhanced PCMs (NEPCMs). The thermal properties of these NEPCMs have been adjudged, in this study. The advanced wet impregnation technique ensures uniform mixing of nanoparticles, and no visual separation or settling issues are encountered up to 2% by weight concentration. An increase in thermal conductivity up to 37% is observed. It is also observed that beyond 2% concentration, partial settling of nanoparticles is observed over a 1-week duration. [GRAPHICS] .

Automated summary

This study focuses on enhancing the thermal properties of PCM-based TES systems by introducing TiO2 nanoparticles into the PCM matrix to form NEPCMs, resulting in an up to 37% increase in thermal conductivity. Beyond 2% concentration, partial settling of nanoparticles is observed over a 1-week duration.