| 초록 |
Recently, there has been increasing interest in the 4680 type cylindrical battery cell, which has improved energy density by five times compared to conventional types for eco-friendly vehicles. For the proper use of the 4680 cell, adequate thermal management is also important to prevent fires caused by battery thermal runaway. In this study, the U and Y parameters for the NTGK model of CFD were obtained through a discharging test of the 18650 cell. The CFD results show that even though the 4680 cell has a multi-tab structure known as a tab-less structure, its thermal safety is worse than that of the 18650 cell with a single tab under natural convection conditions(h = 15 W/m2K). Additionally, the results indicate that the tab-less structure is more effective with active cooling methods such as forced convection(h = 50 W/m2K) and liquid cooling(Tbtm = 23 oC). However, the results from bottom liquid cooling are not good for thermal safety due to a large temperature distribution on the side of the battery cell. This means that air cooling of the cell with a tab-less structure can be an effective battery cooling method as a main or auxiliary means for small battery packs from the perspective of thermal safety. |
