Thermodynamic modeling and calorimetry of nanostructured materials for capacitive thermal management

Transient power dissipation profiles in handheld electronic devices alternate between high and low power states depending on usage. Capacitive thermal management based on phase change materials potentially offers a fan-less thermal management for such transient profiles. However, such capacitive management becomes feasible only if there is a significant enhancement in the enthalpy change per unit volume of the phase change material since existing bulk materials such as paraffin fall short of requirements. In this paper we propose novel nanostructured thin-film materials that can potentially exhibit significantly enhanced volumetric enthalpy change. Using fundamental thermodynamics of phase transition, we calculate the enhancement resulting from superheating in such thin film systems. We further describe the design of a microfabricated calorimeter to measure such enhancements. This work advances the state-of-art of phase change materials for capacitive cooling of handheld devices.