Construction and Thermal Management Properties of Melamine Foam‐Based High‐Thermal‐Conductivity Leak‐Proof Composite Phase Change Materials

ABSTRACT With the increasing demand for energy storage and management, phase change materials (PCMs), particularly organic phase change materials (OPCMs), demonstrate broad application prospects owing to their chemical stability and high enthalpy values. However, OPCMs commonly suffer from leakage and poor thermal conductivity, which limits their practical application. This study employs melamine foam (MF) as the encapsulation matrix, hexadecyl alcohol (HA) as the phase change material, and nanographite (NG) as the thermal conductive filler. Through an electrostatic self‐assembly strategy, a composite phase change material (HA@MF/NG) featuring a three‐dimensional continuous thermal conduction network was constructed. By leveraging the porous structure and surface modification of MF, a three‐dimensional thermal conduction network was constructed along the foam skeleton for NG. This simultaneously achieved high HA loading (81.7%) and leak prevention. The incorporation of NG significantly enhanced the thermal conductivity of the composite material to 0.62 W·m −1 ·K −1 , representing a 210% improvement over pure HA. The composite material exhibits favorable phase transition enthalpy (197.7 J·g −1 ), crystallinity (90.5%), and thermal stability. When applied to thermal management of power batteries, the maximum temperature is reduced by 10.1°C compared to bare batteries. This research provides an effective strategy for preparing high‐performance, leak‐proof, and highly thermally conductive composite phase change materials, demonstrating application potential in fields such as building energy efficiency and electronic thermal management.