电动汽车电池的散热性能

Heat Dissipation Performance of Electric Vehicle Batteries

建立单体电池生热模型,编写用户自定义函数(user defined function,UDF)模拟单体电池的生热,并通过试验验证生热模型的准确性。通过模拟真实工况下单体电池生热量以及测点温度变化分析单体电池生热与冷却空气流速、环境温度的关系,分析不同冷却空气流速与环境温度对电池散热性能的影响。结果表明:电池生热与放电电流基本呈正相关关系;电池中部温度在电池生热时温度较高,在设计冷却通道时应重点考虑;冷却风速越大,电池降温效果越好,但随风速增大降低幅度变小,应根据经济性与实用性选择降温风速;环境温度对电池散热影响很大,在高温时,电池性能大幅度下降,在高温环境使用时应加强电池的散热处理。

The heat generation model of single cell battery is established, and user defined function(UDF) is compiled to simulate the heat generation of single cell battery and the accuracy of the heat generation model is verified by experiments. The relationship between heat generation and cooling air flow rate and ambient temperature is analyzed by simulating the heat generation of single cell and the temperature change of measuring point. The influence of different cooling air flow rate and ambient temperature on the heat dissipation performance of single cell is quantitatively analyzed and the conclusion is that the heat generation of cell is positively correlated with discharge current, and the temperature of the middle part of cell becomes high with the heat generation which deserves due attention when designing the cooling gallery. Although the greater the cooling wind speed is, the better cooling effect we have, the temperature drop decreases as the cooling wind speed increases, so economic and practical cooling wind speed should be selected;the environmental temperature has a great impact on the heat dissipation of the battery. At high temperature, the performance of the battery will be greatly reduced, and the heat dissipation treatment of the battery should be strengthened when it is used in high temperature environment.