Performance optimization of silicon dioxide (SiO2)-encapsulated myristic-stearic acid eutectic as phase change material for thermal energy storage

Phase change materials present a promising solution for efficient thermal energy storage. This study systematically optimized the synthesis parameters for preparing SiO 2 -encapsulated myristic-stearic acid eutectic mixture via the sol-gel method. Through comprehensive investigation of key factors, optimal conditions were identified to produce microencapsulated phase change materials with spherical morphology, smooth surfaces, and superior thermal properties. The microencapsulated phase change materials prepared under optimal conditions exhibited melting and freezing temperatures of 48.40 °C and 46.53 °C, respectively, and latent heats of 133.74 J/g and 123.24 J/g. The encapsulation efficiency and energy storage efficiency reached 74.05% and 71.32%, respectively. Thermal and cycling tests demonstrated excellent leak resistance and thermal stability of this material. Furthermore, microencapsulation significantly improved the thermal conductivity, which was further enhanced by modifying the SiO 2 shell with graphene oxide. The simulation results of battery thermal management validated the practical application value of this material. This work elucidated the synthesis–property relationship for this class of materials, highlighting their potential value in thermal regulation and low-to-medium temperature energy storage.