High-performance thermal energy storage and thermal management via starch-derived porous ceramics-based phase change devices

Low thermal conductivity and leakage of phase change materials (PCMs) have severely limited their applications in thermal energy storage and thermal management of electronic devices. Here, we propose starch-derived porous SiC ceramics to achieve high thermal conductivity and prevent leakage of PCMs simultaneously. Porous SiC ceramics with high thermal conductivity of 30 W/m-K at high porosity of 80% are obtained, benefiting from directional pore structures and dense grains enabled via facile directional freeze-drying of starch combined with liquid silicon infiltration technology. Thermal conductivity and thermal energy storage density of SiC/paraffin composite PCMs (CPCMs) attenuated only slightly by 2.75% and 2.80% after 500 repeated heating-cooling cycles, respectively, confirming their longevity and good stability. The phase change enthalpy achieves 331.56 J/g with high thermal conductivity of 24.27 W/m-K maintained by replacing paraffin with LiOH-LiF eutectics. When applying into transient cooling of high-power chips, the chip temperature is 10 ℃ lower if replacing traditional copper by porous SiC/paraffin CPCMs as a cooling medium. Our work demonstrates a promising route to realize efficient thermal energy storage and thermal management of high-power electronics via starch-derived porous ceramics-based phase change devices.