基于高均温性锂离子电池液冷模组热管理研究

Thermal Management of Lithium-ion Battery Liquid Cooling Module Based on High Temperature Uniformity

为提高锂离子动力电池热管理模组的温度均匀性,提出了一种基于导热块接触面弧度角(简称接触角)梯度增加的液冷式动力电池热管理模组结构。采用数值计算方法,在对单体电池热模型进行实验验证的基础上,研究了接触角(αi)、接触角梯度(Δα)和冷却液入口速度(v)对模组内多个单体电池冷却性能的影响。研究结果表明:单纯增加αi可以降低模组内电池的最高温度(T max),但会导致其温度均匀性降低;采用梯度变化的αi则可以有效改善模组内电池的温度均匀性,该均匀性随着Δα值的增大而提高;且在αi梯度变化的情况下,存在一个可以进一步提升温度均匀性的v。当Δα取15°、v取0.01 m/s时,以3C倍率放电的模组内电池最大温度差(ΔTmax)可以降到4℃以下。

In order to improve the temperature uniformity of the thermal management module of the lithium-ion power battery,a structure of liquid-cooled power battery thermal management module based on the gradient increase of the contact surface radian angle of the heat-conductive block(referred to as the contact angle)was established.Based on the experimental verification of the thermal model of the single cell,a method of numerical calculation was used to study the influence of the contact angle(αi),the contact angle gradient(Δα)and the coolant inlet velocity(v)on the cooling performance of multiple single cells in the module.The research results indicate that simply increasingαi could reduce the maximum temperature(T max)of the battery in the module,but it will cause a decrease in its temperature uniformity.While the gradient change ofαi is adopted,the temperature uniformity of the battery in the module could be effectively improved,and the uniformity increases with the increase of theΔαvalue.And in the case thatαi is gradient changed,there is a v that can further improve the temperature uniformity.WhenΔαis 15°and v is 0.01m/s,the maximum temperature difference(ΔTmax)of the battery in the module discharged at a rate of 3C can be reduced to below 4℃.