Highly thermal conductivity phase change composites enabled by SiCw reinforced graphite foam dual-network for high-efficiency thermal harvesting

Abstract

Phase change composites (PCCs) for the thermal management of high-energy density device are required to have large heat storage capacity and rapid heat conduction and dissipation ability. A graphite foam (GF)/silicon carbide whiskers (SiCw) dual-network skeleton with abundant pore capacity for loading paraffin wax (PW) was designed and fabricated. The highly oriented carbon walls of GFs as the main channels for fast thermal transportation and SiCw formed in GF pores as the secondary heat conductive networks provide GF-SiCw/PW with highly efficient thermal energy harvesting and releasing ability. The prepared GF-SiCw-2 composite loaded with 48.99 wt% of PW exhibits an excellent thermal conductivity of 249.7 W m⁻¹ K⁻¹ and fast thermal response characters. In addition, finite element simulation confirmed that the SiCw network could significantly improve the uniformity of heat transfer inside the PCCs. No PW leakage, homogeneity and superior phase change behavior were observed in GF-SiCw-2/PW. The excellent battery thermal management of GF-SiCw-2/PW was also confirmed. This innovative structure design suggests an efficient route for the development of phase change thermal management system with high heat conductivity, and shows extensive application prospects.