Heat pipes are becoming increasingly popular for managing thermal conditions of electric car battery packs because of their durability, superconductive ability, low maintenance requirements, and lifespan. In this work, suitable working fluid for heat pipes has been identified using multi-criteria decision-making (MCDM) methods for 15 working fluids (Helium, Hydrogen, Oxygen, Nitrogen, Propane, Ethane, Ethanol, R123, Methanol, Toluene, Acetone, (FC-72), Ammonia, (HFE-7000), and water) as potential alternatives and nine decision attributes (thermal conductivity, specific heat capacity, compatibility with heat pipe material, phase change temperature, latent heat of vaporization (LHV), density, viscosity, surface tension, and cost). The criteria weights determined by Criteria importance through inter-criteria correlation (CRITIC) and analytical hierarchy process (AHP) schemes were utilized to prioritize considered working fluids through the application of Multi-Objective Optimization basis on Ratio Analysis (MOORA), Preference ranking organization method for enrichment evaluation (PROMETHEE) and weighted aggregated sum product assessment technique (WASPAS) ranking methods. The findings indicated that water is the best alternative, followed by ammonia. Cost emerged as the most convincing criterion, followed by the compatibility of heat pipe material. The qualitative analysis showed that the integrated weight-based PROMETHEE-II method is the most effective framework for this decision problem, followed by the MOORA and WASPAS methods.