Preparation and Properties of Thermal Management Materials for Electronic Devices Using Stearic Acid/Expanded Graphite Composite Phase Change Material with Enhanced Thermal Conductivity

It is highly feasible to utilize phase change energy storage technology to construct a phase change material (PCM)-based thermal management system for electronic devices. In this paper, stearic acid (SA) was used as the PCM, and expanded graphite (EG) was chosen as the carrier to prepare SA/EG CPCM. The results showed that EG could prevent the melted SA from leaking, and the combination between SA and EG was only physical. When the mass fraction of EG was 11%, the SA/EG CPCM had good shape stability with a phase change temperature (T_m) of 67.2 °C, a phase change enthalpy (∆H_m) of 204.4 J/g, and a significantly increased in thermal conductivity (6.432 W/(m·K)). In addition, simulation test experiments showed that the peak value of the heating surface was weakened by about 20 °C in the heating stage after loading the CPCM on the electronic device. Therefore, the resultant SA/EG CPCM in this work had great application value.