Towards High Energy Density, High Conductivity Thermal Energy Storage Composites Conference Paper uri icon


  • Thermal energy storage (TES) materials absorb transient pulses of heat, allowing for rapid storage of low-quality thermal energy for later use, and effective temperature regulation as part of a thermal management system. This paper describes recent development of salt hydrate-based TES composites at the Air Force Research Laboratory. Salt hydrates are known to be susceptible to undercooling and chemical segregation, and their bulk thermal conductivities remain too low for rapid heat transfer. Here, we discuss recent progress towards solving these challenges in the composite system lithium nitrate trihydrate/graphitic foam. This system takes advantage of both the high volumetric thermal energy storage density of lithium nitrate trihydrate and the high thermal conductivity of graphitic foams. We demonstrate a new stable nucleation agent specific to lithium nitrate trihydrate which decreases undercooling by up to 70% relative to previously described nucleation agents. Furthermore, we demonstrate the compatibility of lithium nitrate trihydrate and graphitic foam with the addition of a commercial nonionic silicone polyether surfactant. Finally, we show that thermal conductivity across water-graphite interfaces is optimized by tuning the surfactant concentration. These advances demonstrate a promising route to synthesizing high energy density, high thermal conductivity TES composites.

name of conference

  • ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer

published proceedings

  • ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer

author list (cited authors)

  • Shamberger, P. J., & Forero, D. E.

publication date

  • January 1, 2012 11:11 AM