Shape-stabilized phase change material based on MOF-derived oriented carbon nanotubes for thermal management of lithium-ion battery

Phase change material (PCM) is a suitable candidate for thermal energy storage as its high latent heat and narrow temperature fluctuations during phase change process. However, low thermal conductivity and poor shape stability seriously hinder the large-scale utilization of phase change materials. Here we fabricated the highly oriented N-doped carbon nanotubes (N-CNTs) derived from metal-organic frameworks (MOFs) by a facile and high-yield strategy. Then the N-CNTs/docosane composite PCM (CPCM) was fabricated with the as-synthesized N-CNT as the supporting material and docosane as the functional material. It can be revealed that the shape stability of docosane was significantly enhanced by integrating with N-CNTs. The CPCM possessed a thermal conductivity increased by 197.47 % (0.5286 W·m−1·K−1) than that of docosane. Besides, the CPCM exhibited an excellent cycle performance with ultrahigh retention of latent heat (99.95 % in melting process and 99.94 % in freezing process) after 20 melting-freezing cycles. Further exploration reveals that the electronic conductivity of the CPCM increases to 2928.26 S·cm−1. The CPCM was then used to fabricate a flexible thin film for the thermal management of lithium-ion battery (LIB). In the charge-discharge cycle performance test, the maximum temperature of LIB is about 2 °C lower by the utilization of CPCM film. This exploration exhibits great potential in stimulating the development of PCMs and provides a new technology for LIB thermal management.