A compact and lightweight hybrid liquid cooling system coupling with Z-type cold plates and PCM composite for battery thermal management

In this study, a hybrid liquid cold plate design containing Z-type parallel cooling channel and PCM/aluminum foam composite, in conjunction with a novel delayed cooling strategy, is proposed to provide a compact, lightweight, and energy efficient solution for battery thermal management systems (BTMSs). A total of nine different cold plate designs, including one baseline cold plate without PCM composite and eight hybrid cold plates containing PCM composite, are analyzed systematically to demonstrate the superior cooling performance of the proposed cooling design. Specifically, the average temperature of battery surface and total power consumption performance of each design are analyzed and compared at a battery discharging rate of 1C under both continuous and delayed cooling schemes. Subsequently, two selected designs with superior cooling performance as well as the baseline cold plate are further investigated to discuss the effectiveness of hybrid liquid cold plates for cooling batteries at high discharge rates. The results show that the optimum hybrid cold plate design, which only weighs half of the baseline cold plate, can provide more than 50% reduction in the total pumping power while achieving the same cooling performance (i.e., with the average battery temperature controlled within 40 °C) compared with the baseline cold plate at battery discharging rates of 1C, 2C and 3C. These results can potentially provide important guidance to the design of advanced cooling systems for lithium-ion batteries.