Numerical investigation of air cooling system for a densely packed battery to enhance the cooling performance through cell arrangement strategy

Abstract

Summary Recent studies have revealed that the operating temperature and temperature uniformity within the battery pack significantly affected its performance. In this study, the air‐cooled thermal management system of a densely packed battery pack was numerically investigated under different cell arrangements such as inline, offset, and staggered configurations to evaluate their cooling characteristics. The effects of inlet ambient air velocity and discharge rate were also evaluated to guarantee the temperature of the battery pack operated within an optimal range. The results revealed that increased airflow enhanced the cooling performance of the system but also increased the flow resistance, resulting in large power consumption. A battery pack operating at the low discharge rate of 0.5C might not require forced air‐cooling. For fast discharge rates, especially over 2C‐rate, forced air‐cooling would not be economical for battery thermal management. A narrow cell‐to‐cell distance can decrease the cell temperature and also improve space utilization; however, it increased the power consumption for circulating air and the risk of a thermal runaway propagation. A trade‐off between thermal dissipation and energy consumption was investigated. After comparing several circumstances, the offset layout was the appropriate choice for the air‐cooled thermal management system, followed by the inline layout. It satisfied the requirements of low power consumption, high space utilization, and efficient cooling performance; in particular, the offset layout consumed about 43.1% less power than the inline layout, while losing space utilization of only 6.3%.

Design and optimization of a novel reverse layered air‐cooling battery management system using U and Z type flow patterns

“…To ensure good temperature uniformity and good cooling performance, the value of ΔT should be optimized as low as possible, meanwhile T max should be smaller than that of the initial design T max_init , and ΔP should not be raised over 10% higher than that of the initial design ΔP init . The scheme of the optimization of the problem in this work can be given by Equation (17).…”

“…Yu et al 16 depicted that air natural convection could only assure the maximum temperature and temperature difference within the optimal range at 0.5C (C standards for the charge/discharge rate of the battery respecting its normal capacity) discharge rate. Saechan and Dhuchakallaya 17 pointed out that the heat generation of a battery under 0.5C discharge rate can be dissipated with natural convection, and that under 1C can be dissipated using air‐forced cooling with the airflow velocity of 1 m/s. Furthermore, forced air‐cooling has also been proven to be able to control the temperature rise within the desired optimal range 2,18 …”

“…Yang et al 20 found that increasing the spacing increases the average temperature but decreases the power consumption and temperature difference. Saechan and Dhuchakallaya 17 numerically investigated the effects of different structural features as inline, offset and staggered arrangements as well as the uneven spacing on the cooling performance. It has been found that the offset layout has the best performance then followed by the inline layout, and the uneven spacing provides efficient cooling performance with less power consumption and space utilization.…”