CFD simulation of effect spacing between lithium-ion batteries by using flow air inside the cooling pack

Abstract

The CFD simulation of this study shows the impact of airflow with varying Reynolds numbers on heat transfer improvement with cooling lithium-ion batteries at varied battery row spacing. Air was used as a cooling fluid to remove heat from lithium-ion batteries by flowing within the cooling pack during testing of four different spacing ranges (S = 1–4 mm). The Reynolds numbers vary from15,000 to 30,000 in the current analysis. The average Nu numbers are augmented through increasing Reynolds numbers for all types of cooling fluids. The CFD results show that the Nu number increases as spacing increases. The temperature of the single cell drops with increasing the Re or the flow rate since the liquid in the pack exchange with a new cold HTF at a faster rate. The average Nu number is directly proportional to the Re number and the spacing between the neighbor cells. Further, the temperature of the cells located closer to the inlet section is always lower than those closer to the outlet section because of the temperature differences between the cells and the HTF. This study has confirmed that the flowing air with high Re and highest spacing S = 4 mm has a major impact on thermal dissipation and rapid heat transfer improvement from lithium-ion batteries in the cooling pack, which leads to improved electrical performance and increase the life of lithium-ion batteries.