Design and Numerical Study of Microchannel Liquid Cooling Structures for Lithium Batteries

To investigate the microchannel liquid cooling system of 18650 cylindrical lithium battery packs, cooling systems with varying numbers of microchannels are developed and they are analyzed through numerical simulations using COMSOL software. The findings reveal that lower coolant inlet temperatures correspond to lower maximum temperatures during discharge, with temperatures decreasing closer to the inlet. When the coolant passes through a 3.6 mm diameter or at an inlet flow rate of 0.1 m s −1 , an increase in Reynolds number results in a decrease in the highest temperature of the cells. However, this temperature reduction slows down when Re exceeds 400. The annular channel cooling structure demonstrates superior cooling effects and temperature uniformity. Optimization opportunities exist to reduce the number of inlets. The dual‐inlet and dual‐outlet cooling structure has been enhanced by adjusting the number of channels in the annular channel design. This modification has resulted in a maximum temperature reduction of 4.62 K and a temperature difference of less than 5 K compared to the initial reference group, demonstrating effective cooling performance.