Achievement

Phase change materials such as paraffin waxes and plant derived oils are of interest as thermal energy storage materials, especially for low temperature waste heat recovery. An issue in the implementation of these materials is their low thermal conductivity, resulting in long time scales to charge and discharge thermal energy. To address this issue, attempts have been made to increase the thermal conductivity of the waxes and oils by adding high thermal conductivity particles. However, the stability of the suspended particles remains a challenge, as settling of the particles results in degradation in thermal conductivity and performance over time. In this work, IGERT Fellow Anne Mallow and Prof Graham are developing methods to suspend graphite nanoplatelets in paraffin wax as well as commercial plant derived phase change materials. State of the art measurements demonstrated graphite particles remain suspended in paraffin for up to 1wk, demonstrating the challenge of this approach.