Tailoring thermal insulation in carbon fiber reinforced composites: Pore-preserved aerogels and thermoplastic matrix engineering

There is an increasing demand for battery pack housing materials that offer lightweight, mechanical, and thermal insulation properties to prevent thermal runaway caused by external mechanical and/or thermal stimuli. In this study, by applying a polypropylene (PP) chain-length control strategy to impregnate micropores between carbon fibers (CFs) and to maintain nanopores within the incorporated silica aerogel (SA), a CF reinforced thermoplastic (CFRTP) with superior thermal insulation properties was proposed. The PP chain length, used as matrix, was identified as the most important structural factor determining the extent of CF impregnation and preservation of the SA nanopore structure. Additionally, the optimized CFRTP, in which SA nanopores were preserved and CF was well-impregnated, exhibited excellent thermal insulation with a value of 0.045 W/m·K. The excellent thermal insulation properties of the proposed CFRTP make it a promising candidate for applications in electric vehicle battery pack enclosures.