The present work aims to perform a thermoeconomic assessment of a battery pack integrating a novel compact coolant system through which Al2O3, TiO2, CuO, and Cu nanofluids flow at different Reynolds numbers and concentrations. The inlets in the north and west and the outlets in the south and east directions are found to be the best configuration since the least number of batteries exhibits higher temperatures. A nanofluid-based cooling system offers an improvement of 15 K in battery core temperature when compared to the pack without any coolant system at 200 s; however, a reduction of 0.3 K is noticed when compared to water. CuO nanoparticles perform better at a low concentration of 2%, whereas Cu particles have an advantage over other nanoparticles at a concentration greater than 2%. An economic analysis of the nanofluid has also been performed, eradicating the idea of using Cu–water nanofluid in the coolant system owing to its significantly high cost. Though the cost of the CuO and Al2O3 nanofluid is 13 times lower than Cu, using pure water as the coolant is recommended since there is a marginal reduction of 0.1–0.3 K in the battery pack temperature when water is replaced by nanofluid.