Comparative study of thermal management systems with different cooling structures for cylindrical battery modules: Side-cooling vs. terminal-cooling

Indirect-cooling through cooling plate is a common way in the design of liquid-based battery thermal management system (BTMS), which can be divided into side-cooling and terminal-cooling according to the position arrangement of the cooling plates. In this work, comparative investigations are performed to analyze the specific merits and demerits between these two cooling structures and further understandings are provided for the heat dissipation mechanisms of BTMSs for the cylindrical battery modules. It is found that the side-cooling BTMS exhibits a better ability in the temperature rise control with a maximum temperature (Tmax) of 30.84 degrees C at the end of 1 C discharge compared with the terminal-cooling one where corresponding Tmax rises to 35.48 degrees C. But meanwhile, it encounters an inherent drawback on the temperature uniformity with a maximum temperature difference (Delta Tmax) of 5.76 degrees C after 1 h discharging due to the low radial thermal conductivity of the batteries, which forms a significant thermal gradient along its thermal transport paths. In contrast, corresponding Delta Tmax in the terminal-cooling case is only 2.86 degrees C. Effects of coolant velocity and channel number on the heat dissipation performances of the side-cooling and terminal-cooling BTMSs are examined and further, different strategies are proposed and tested for these two cooling structures respectively to ameliorate their heat dissipation performances based on their different characteristics in the heat transport paths and thermal field distributions. The results could provide useful guidance for the future design of BTMS for the cylindrical battery modules.