A comprehensive review of nano-enhanced phase change materials for electric vehicle and power electronics thermal management

Nano-enhanced phase change materials (NEPCMs) are a novel small-scale passive technique for thermal management in electric-cars and high-power electronics. This paper summarises the innovations in materials, mechanistic-insights, and system-level performance of NEPCMs and quantifies reported advances to guide engineering execution. Nano-additives based on carbon, including graphene (40%–120%), carbon nanotubes (25%–80%), metal-oxide fillers (20%–60%) and MXenes (60%–150%), enable significant increases in thermal-conductivity, dependent on loading and dispersion-quality. The scalable-processing and low-temperature carbon-additive routes can reduce material-costs by 20%–35% compared to early laboratory-formulations and can thus match active cooling in cost-performance at moderate heat-fluxes. Performance enhancement approaches, such as hybrid PCMs, thermo-responsive and multi-functional PCMs, and their application in practical scenarios, especially in EV battery thermal control, power-electronics cooling and rapid charging are addressed. It also discusses the major issues of NEPCM implementation, including dispersion-stability, thermal-degradation and nanotoxicity, and suggests future research directions to mitigate these shortcomings.