In this study, the thermal performance of a compact heat sink thermoelectric cooling module with water, nanofluid, and ferrofluid as the coolants is investigated experimentally. The TiO2 nanofluid and Fe3O4 ferrofluid were tested at concentrations of 0.005% and 0.015%, respectively. The dummy battery pack was filled with water under a constant temperature and represented as a heat load. The results reveal that the Fe3O4 ferrofluid showed a maximum heat transfer rate 11.17% and 12.57% higher, respectively, than that of the TiO2 nanofluid and water. The TiO2 nanofluid and Fe3O4 ferrofluid with a 0.015% concentration enhanced the Peltier effect by lowering the contribution of the Fourier effect of the thermoelectric cooler (TEC), decreasing the temperature difference of the TEC cooling module by 4.6% and 9.6%, respectively, which decreases the thermal resistance of the heat sink by 7% and 14%, respectively. More importantly, the use of nanofluids and ferrofluids with a 0.015% concentration as coolants increased the pressure drop significantly, by 0.5 kPa and 2.7 kPa, respectively, compared with water.