Enhanced solar-thermal and electro-thermal storage performance of solid-solid composite phase change material

Abstract

Phase change material (PCM) is a highly sought-after thermal storage medium, but cannot directly reserve solar energy and electricity. In this study, a pentaglycerine (PG)-based composite solid-solid phase change material (SSPCM) was developed with the ability to convert and store solar-thermal and electro-thermal energy. The composite was prepared using a high temperature melting process with graphite paper (GP) and carbon nano tube (CNT) as functional additives. The performance tests showed that the composite has a phase change temperature of 80.5 °C, latent heat of 145.6 J/g, supercooling degree of 7.9 °C and electrical conductivity of 15.3 S/m. This composite could undergo solid-solid phase change and store solar energy in the form of latent heat under simulated sunlight. The phase change process can also be driven by direct current, with a 10 V power supply increasing the temperature of the composite to 90 °C within 32 min. These properties make the developed SSPCM promising for energy storage applications.