Thermal analysis of large-capacity LiFePO 4 power batteries for electric vehicles
Thermal analysis of large-capacity LiFePO 4 power batteries for electric vehicles
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DOI：
10.1016/j.jpowsour.2015.06.129
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发表时间：
2015-10
影响因子：
9.2
通讯作者：
Chunjing Lin;Sichuan Xu;Z. Li;Bin Li;Guofeng Chang;Jinling Liu
中科院分区：
文献类型：
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作者：
Chunjing Lin;Sichuan Xu;Z. Li;Bin Li;Guofeng Chang;Jinling Liu
优秀的热管理系统设计需要对动力电池的热行为有很好的理解。本研究研究了40 Ah C/ lifepo4柱形电池的电化学和热性能，重点研究了混合充放电循环中温度对电池容量的影响。此外，在不同的电流速率下，电池在充电和放电过程中产生的热量和能量效率是确定的。实验结果表明，在一定温度范围内，充放电容量随温度的升高而显著增大。此外，当电池在0.33 C - 2℃的电流和25-45℃的温度下运行时，能量效率达到95%以上。建立了基于实验得到的内阻和熵系数的热数学模型。利用该模型，根据实验测量的比热值和理论计算的比热值对电池温度的升高进行了模拟。模拟结果表明，温度的升高与实验值吻合较好，比热的测量结果优于比热的计算结果，并且随着温度的升高，产生的热量减小。
Excellent design of a thermal management system requires good understanding of the thermal behaviors of power batteries. In this study, the electrochemical and heat performances of a prismatic 40 Ah C/LiFePO4battery are investigated with a focus on the influence of temperature on cell capacity in a mixed charge–discharge cycle. In addition, the heat generation and energy efficiency of a battery are determined during charge and discharge at different current rates. The experimental results indicate that in certain temperature ranges, both the charging and discharging capacities increase significantly as the temperature increases. In addition, the energy efficiency reaches more than 95% when the battery runs at a current rate of 0.33 C–2 C and temperature of 25–45 °C. A thermal mathematical model based on experimentally obtained internal resistances and entropy coefficients is developed. Using this model, the increase in the battery temperature is simulated based on specific heat values that are measured experimentally and calculated theoretically. The results from the simulation indicate that the temperature increase agrees well with the experimental values, the measured specific heat provides better results than the calculated specific heat and the heat generated decreases as the temperature increases.