Transient thermal analysis of a thermoelectric-based battery thermal management system at high temperatures

In response to the need for rapid cooling of batteries operating at elevated temperatures (333.15 K), this study proposes a hybrid battery thermal management system (BTMS) that integrates liquid cooling, vapor chambers (VCs), and thermoelectric coolers (TECs). An unsteady multiphysics model is established to evaluate the thermal behavior of the BTMS, incorporating heat transfer, fluid flow, and electric field coupling. Comprehensive comparative analysis reveals that a BTMS without TECs fails to cool the battery below 313.15 K, while the proposed BTMS significantly outperforms systems that utilize air cooling methods. Within the operational ranges of coolant flow rates below 0.12 m/s and TEC input currents below 3 A, an increase in both parameters improves the thermal behavior of the BTMS. However, excessively high flow rates and currents are not desirable due to diminishing returns. Specifically, at a coolant flow rate of 0.12 m/s, TEC input current of 3 A, and discharge rate of 3 C, the BTMS achieves a cooling time of 630 s, a period of ΔTmax > 5 K lasting 640 s, and a cooling rate of 1.905 K/min. Moreover, the system remains effective even at higher discharge rates of 4 C and 5 C, meeting the thermal management requirements under these conditions. This research offers novel insights into the thermal management of batteries under high-temperature conditions, contributing to the development of more effective cooling strategies.