Compact thermal management for high-density lithium-ion batteries: Liquid cooling solutions

Efficient thermal dissipation technology is crucial for compact energy storage battery packs with high heat flux density, representing a major bottleneck in technological advancement. This study proposes a thermal management strategy: a compact liquid-cooling system designed to optimize the thermal efficiency of lithium-ion battery (LIB) modules. Utilizing computational fluid dynamics (CFD) simulation technology, this study focuses on analyzing the impact of the height of the liquid cooling tube (Delta h), the angle of contact between the tubes and the batteries (B), the velocity of the cooling liquid at the inlet (vw), and the temperature of the cooling water (T) on the thermal performance of the battery pack. To simplify the analysis process and achieve rapid optimization, this study integrates orthogonal experimental design, genetic aggregation, and the rank sum ratio (RSR) method, avoiding extensive CFD predictive calculations and quickly obtaining the optimal structural solution. The results show that when the height of the cooling tube h increases from 0 mm to 6 mm, the maximum temperature of the battery pack (Tmax) decreases from 24.0 degrees C to 23.7 degrees C, while the system mass (m) correspondingly increases from 0.106 kg to 0.125 kg, and the energy consumption (W) increases from 52,767 J to 53,140 J. When B increases from 30 degrees to 90 degrees, Tmax decreases from 25.7 degrees C to 23.7 degrees C, m increases from 0.082 kg to 0.118 kg, and W increases from 52,533 J to 53,032 J. When vw increases from 0.2 m/s to 1 m/s, Tmax decreases from 27.5 degrees C to 23.6 degrees C, and W correspondingly increases from 52,565 J to 53,163 J. When T increases from 15 degrees C to 25 degrees C, Tmax increases from 18.9 degrees C to 28.7 degrees C, while W decreases from 53,453 J to 52,384 J. By comprehensively optimizing these parameters, the optimal system configuration was determined: Delta h = 0 mm, B = 60 degrees, vw = 0.93 m/s, T = 22.5 degrees C. Compared to the initial solution, W of the optimal solution was reduced by 350 J, and m was reduced by 0.013 kg. The results of this study confirm that the proposed thermal management system significantly improves the thermal performance of LIB modules, providing a compact, multi-objective solution for high-power applications.