基于波浪形液冷通道的锂离子电池热管理系统模拟分析

Simulation and Analysis of Lithium-Ion Battery Thermal Management System Based on Wavy Liquid Cooling Channel

随着电动汽车的普及,液体冷却的电池热管理系统因其高效散热和低成本而被广泛应用。提出了一种波浪形液冷散热结构,并利用伪二维电化学模型和三维传热模型构建了一个电池组模型,考察了一个5×5的LiFePO_(4)/石墨电池组中的产热与传热过程,研究了放电倍率、环境温度、冷却液温度、冷却液流速和冷却管道与电池接触面积对电池组散热性能的影响。结果显示,高放电倍率会导致电池的最高温度和最大温差上升;低环境温度和冷却液温度可以有效降低电池组温度,但过低的环境温度和冷却液温度会导致电池组的较大温差。当环境温度为室温时,冷却液温度为293.15 K时最佳;冷却液流速对电池组的散热性能影响较小;电池与冷却管道接触面积越大,电池组的最高温度和最大温差会降低,然而考虑到经济成本,电池与冷却管道的最佳接触角度为90°。这项研究为锂离子电池组的热管理系统设计提供了理论指导。

With the popularization of electric vehicles,liquid-cooled battery thermal management systems have been widely used due to their high heat dissipation efficiency and low cost.A unique wavy liquid-cooled heat dissipation structure was utilized,and a battery pack model was constructed using a pseudo-two-dimensional electrochemical model and a three-dimensional heat transfer model.The study examined the effects of discharge rate,ambient temperature,coolant temperature,coolant flow rate,and contact area between the coolant pipe and the battery on the thermal performance of a 5×5 LiFePO_(4)/graphite battery pack.The results showed that a high discharge rate would cause the maximum temperature and maximum temperature difference of the battery to rise.Low ambient temperature and coolant temperature can effectively reduce the temperature of the battery pack,but too low ambient temperature and coolant temperature can cause a larger temperature difference in the battery pack.When the ambient temperature is at room temperature,the optimal coolant temperature is 293.15 K.The coolant flow rate has little effect on the thermal performance of the battery pack.The larger the contact area between the battery and the coolant pipe,the lower the maximum temperature and maximum temperature difference of the battery pack.However,considering the economic cost,the optimal contact angle between the battery and the coolant pipe is 90°.This study provides theoretical guidance for the design of thermal management systems for lithium-ion battery packs.