Ultra-low voltage driven form-stable phase change material with enhancing thermal conductivity

Electric-driven phase change materials (PCMs) are of great significance to improve energy utilization by electrothermal conversion and heat storage. However, the high working voltage can easily cause safety hazards, so it is vital to reduce the driving voltage. In this work, the polyethylene glycol (PEG) is constrained in the gel to form a semi-interpenetrating polymer network (semi-IPN). Then filled the phase change gel into the conductive network of foamed copper (FCu) to prepare the FCu/sodium polyacrylate (PAAS)/N,N'-Methylenebisacrylamide (MBA)/PEG composite PCMs with a like reinforced concrete structure. The PCMs exhibit strong form stability, enhanced thermal conductivity, and ultra-low driving voltage. The phase change enthalpy was 90.1 J/g, the electrical conductivity was 217.39 S/m, and the electrothermal conversion efficiency reached 65.49 % at 0.80 V. Moreover, the thermal storage and release rate of the PCMs was enhanced 52.41 % and 62.88 % with the introduction of the FCu.