Experimental assessment and comparison of single-phase versus two-phase liquid cooling battery thermal management systems

Abstract

Liquid-based cooling systems are becoming the dominant approach for thermal management of lithium-ion batteries due to the favorable specific heat capacity and heat transfer coefficient. In this study, single-phase and two-phase liquid cooling (SPLC and TPLC) systems are experimentally evaluated and compared in two indirect-contact modes for a large-format lithium-ion battery. Two commonly used liquid coolants, e. g. Novec 7000 and deionized water, are utilized as heat transfer fluids. The experimental results reveal that both SPLC and TPLC systems with coolant flow exhibit excellent ability to control temperature spikes, and the SPLC system using deionized water outperforms the TPLC system using Novec 7000 in terms of cooling capability. Additionally, the cooling effect of copper foam configuration surpasses that of straight fin configuration. The SPLC system equipped with copper foam holds the best cooling performance, with a maximum surface temperature of 32.1 °C and a largest temperature difference of 1.8 °C observed over the 3C discharge process at a flow rate of 10 mL/min. These findings are valuable for designers seeking to develop efficient and practical thermal management systems for large-format lithium-ion batteries.