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In this paper, Al 2 O 3 -SiO 2 -B 2 O 3 glass-ceramic was prepared and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), further, the porosity was detected by Archimedes principle, thermo physical properties were investigated by differential scanning calorimeter (DSC), respectively. The phase composition was detected by XRD, and the morphology was observed by SEM. The results indicated that the thermal conductivities of the Al 2 O 3 -SiO 2 -B 2 O 3 glass-ceramic were between 1.3 and 1.5 W·(m·K) −1 , and the material had good thermal stability in the range of 300–900 °C. The porosity and apparent density were increased with the temperature. The porosity of Al 2 O 3 -SiO 2 -B 2 O 3 glass-ceramic in ranging from 1.2 to 9.6%, the apparent density were between 2.12 and 2.67 g·cm −3 , and heat capacities were between 0.64 and 0.79 kJ/(kg·K). All the results indicated that the Al 2 O 3 -SiO 2 -B 2 O 3 glass-ceramic can be applied as encapsulation material in high temperature latent thermal energy storage.

The present work focused on the preparation and characterization of a new thermal storage material applied in thermal energy management. X-ray diffraction (XRD) results showed that Expanded Perlite (EP) has a good thermal stability varying from 300 °C to 900 °C. Morphology of scanning electron microscopy (SEM) revealed that sodium nitrate is uniformly encapsulated and embedded in the three-dimensional network structure of EP. Fourier transform infrared (FT-IR) spectroscopy indicated that the EP is physically combined with the nitrate salt. Thermo-gravimetric analysis (TGA) and differential Scanning Calorimeter (DSC) indicated that the composites have good thermal stability. The adsorption capacity of loose EP was 213.21%. When the EP mass fraction varying from 10% to 60%, thermal conductivity decreased with the content of EP increased, and the highest thermal conductivity is 1.14 W (m K)−1 at 300 °C. SEM revealed the network structure of EP provided thermal conduction paths which enhanced the thermal conductivity of the composites. All results indicated that EP could be a good adsorption material to be applied in the thermal storage fields.

Inorganic hydrated salt Ba(OH)2⋅8H2O is one of most potential thermal storage materials in the low–medium temperature range due to its highest latent heat per unit volume. Thermal stability tests, super-cooling and corrosion investigations of Ba(OH)2⋅8H2O on four metal materials were conducted, thermal cycling tests revealed that Ba(OH)2⋅8H2O as PCM had a good thermal reliability, the super-cooling increased and then stabilized after 300 thermal cooling cycles, the corrosion investigations showed that the copper had the strongest resistance corrosion performance. Furthermore, using copper as finned-tube and cylindrical shell and Ba(OH)2⋅8H2O as phase change material (PCM), numerical simulation of heat exchangers was carried out. The simulation results showed higher heat transfer efficiency was associated with the greater temperature difference between PCM and heating/cooling wall. The large fin width or small fin pitch could help extend the surface of the heat exchange, and contribute to improving the heat transfer efficiency.