Carbon matrices with different pore structures as heat transfer intensifier in paraffin wax/carbon thermal energy storage system

Graphite foam, carbon felt and compressed expanded natural graphite (CENG) were used to increase the heat transfer ability of paraffin wax as latent heat storage (LHS) medium. Structure and thermal properties of the paraffin wax-carbon LHS system were characterized using the scanning electron microscopy, laser flash technique and differential scanning calorimetry. Results indicated that the thermal conductivities of paraffin wax-graphite foam, paraffin wax-carbon felt and paraffin wax-CENG systems were enhanced by a factor of 437, 14 and 25 times, respectively, compared with pure paraffin wax and their latent heats were 42.34J/g, 48.38J/g and 57.82J/g respectively.