Design,Preparation And Application Of Phase-Change Solar-thermal Energy Storage Composites

Photothermal conversion is an efficient and clean way to harvest solar energy.Due to the intermittency and low energy density of solar radiation,solar energy storage is the key technology to overcome the disadvantages.Among them,phase-change thermal energy storage has attracted much attention due to its high energy density and relatively stable heat releasing temperature.However,phase change materials generally have problems such as low thermal conductivity,easy leakage after melting,and low absorption of sunlight,which severely limits their applications in the field of solar energy storage.Currently,phase-change solar-thermal energy storage composites are expected to enhance the performance.At present,the research in this field mainly rely on high thermal conductivity fillers to improve the thermal energy storage performance of materials,which usually only limitedly enhances the charging and discharging rates but sacrifices the favorable characteristics of phase change materials.In this paper,to improve the slow charging rate of traditional heattransfer-based charging approach,we propose a new solar-thermal energy storage mechanism based on the rapid transmission of photons,which preserves the high enthalpy and phase transition temperature of phase change materials,and achieves a fast,efficient and large-capacity solarthermal energy storage.In order to solve the leakage problem of phase change materials and explore new applications of solar-thermal energy storage,we further propose a solar-thermal energy storage mechanism based on the rapid thermal conduction of three-dimensional heat transfer network.By designing and preparing phase-change solar-thermal energy storage composite with special structure,we explore the innovative applications of latent solar-thermal energy storage in the field of thermal therapy.Proved by experimental measurement and theoretical simulations,the three-dimensional high thermal conductivity network can significantly shorten the charging time and greatly prolong the healing duration of the thermal therapy.