汽车专栏
Automobile
纯电动汽车磷酸铁锂电池的热特性参数辨识和热仿真分析
刘杨,赵中阁
(中国航空综合技术研究所,北京100028)
摘要:磷酸锂铁作为新型的高能化学电源,常被用作纯电动汽车电池。因此,需要对磷酸锂特电池的热性能进行研究。本文以某型号磷酸锂铁电池单体为研究对象。研究磷酸锂铁电池的生热和传热机制。建立电池的电化学一热耦合模型,并对电池的热物性参数进行计算,对电池的生热速率模型进行选取。应用计算得到的电池热物性参数,对磷酸锂铁电池单体进行CFD模型建立。应用非接触式热测量方式对CFD模型进行模型校核。运用FloTHERM热分析软件对磷酸锂铁电池组在不同散热条件下的温度场进行仿真,为电池组的设计和优化提供参考和指导。
关键词:磷酸铁锂电池;热特性;CFD仿真;热测试
中图分类号:TM911文献标识码:A文章编号:1004-7204(2020)05-0013-07
Thermal Characteristic Analysis and Simulation of Lithium Iron Phosphate
Battery
LIU Yang,ZHAO Zhong-ge
(China Aero-polytechnology Establishment,Beijing100028)
Abstract:As a new type of high-energy chemical power supply,lithium iron phosphate ba/tteries are often used as power source of pure electrie vehicles.Therefore,it is necessary to study the thermal performance of lithium iron phosphate batteries.A certain type of lithium iron phosphate battery cell is taken as research object in this paper to study the heat generation and transfer mechanism of lithium iron phosphate batteries.The thermo-physical parameters of the cell are calculated and the heat generation model is selected.Besides,the CFD(Computa/tional Fluid Dynamics)model of the lithium iron phosphate battery cell is established out of the thermophysical parameters.FloTHERM is used to Simulate the temperature profile of the cell under different working conditions.The temperature is also tested by non-contact temperature measurement.It provides reference and guidance for battery pack design and optimization.
北京电动汽车Key words:lithium iron phosphate ba/ttery;thermal characteristics;CFD Simulation;thermal test
引言
温度影响着磷酸铁锂电池的性能、安全性和寿命。温度过髙不仅会损坏磷酸铁锂电池的使用寿命,还会造成磷酸铁锂电池的热失控,导致车辆起火,危及乘客的安全E。安全性是电动汽车的基本要求。因此有必要对磷酸铁锂电池的热特性进行分析,提高电池的散热能力。
热仿真已经成为研究锂离子电池热问题的主要方法之一。建立准确的热模型,有利于高效地获得电池的热特性,进而进行精确的电池热设计。磷酸铁锂电池的主要发热组成为可逆热和不可逆热两部分冋。充放电过程中的爛系数影响着可逆热,而电极的极化热决定着不可逆热。磷酸铁锂电池热物理参数的准确识别对电池热仿真的准确性也起着关键作用[3]o电池热
13环境技术/Environmental Technology