摘要
锂离子电池以其高能量密度、低自放电率等优点,广泛应用于新能源汽车。本文以圆柱18650锂离子电池为研究对象,建立了锂离子电池的详细热模型,内部包括正负极、隔膜等多层结构。通过Bernardi方程求解焦耳热与熵变产热率,结合有限元分析(FEA),对三元锂圆柱电池放电过程的热特性进行数值研究,得到不同放电倍率下,电池的温度分布以及温升曲线。结果表明,焦耳热对电池的温升起主导作用,熵变热的影响相对较小,在5C放电情况下占比仅8%。与自然对流相比,强迫对流下,电池的最高温度显著降低,但是电池的内外温差也会加大。
Lithium-ion batteries,with its excellent characteristics such as high energy density and low self-discharge rate,are widely used in new energy vehicles.In this study,a detailed thermal model is established for 18650 cylindrical lithium-ion battery.The simplified model by adopting a cylindrical coordinate is employed.Theoretical thermo-electric model conjugated with finite element analysis to numerically study the thermal behavior(temperature distributions and profiles)of LiNiCoMnO2/C cylindrical battery during different discharge rates.The results show that the contribution of heat source due to joule heating is significant during the discharge process,and the effect of entropy heating is relatively small.Compared to the results of natural convection,the maximum temperature of the battery is significantly reduced under forced convection,while the temperature difference between the inside and the outer surface increases.
作者
朱泽华
张恒运
ZHU Zehua;ZHANG Hengyun(School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)
出处
《智能计算机与应用》
2020年第7期210-216,共7页
Intelligent Computer and Applications
基金
国家自然科学基金(51876113)
