基于大倍率电流脉冲的动力锂离子电池阻抗模型优化  

Optimization of an impedance model for power Li-ion batteries based on a large multiplier current pulse

作　　者：李欣雨 韩雪冰[1] 卢兰光[1] 李建秋[1] 欧阳明高[1] LI Xinyu;HAN Xuebing;LU Languang;LI Jianqiu;OUYANG Minggao(State Key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学汽车安全与节能国家重点实验室,北京100084

出　　处：《储能科学与技术》2023年第5期1686-1694,共9页Energy Storage Science and Technology

基　　金：北京市科技计划课题任务书(Z221100005222002)。

摘　　要：随着中国能源转型的推进,动力电池使用量逐年上升。随之而来的电池安全运行问题逐渐凸显。在保障电池稳定运行的电池管理系统(Battery management system,BMS)中,等效电路模型(Equivalent circuit model,ECM)是其工作的基础核心。而目前的电池管理系统模型主要为线性模型,且受限于计算量和芯片的计算能力,无法合理表达电池在极端工况下,如大功率等情况下的非线性特征。针对这一问题,本文从可用功率角度出发,对电池进行了不同倍率的脉冲放电实验,分析了不同倍率情况下电池内阻的非线性特征,改进了电池的等效电路模型,建立了高倍率条件下阻抗随电流的变化关系。实验结果表明改进后的等效电路模型的模型误差为1.74%,远小于旧模型的8%。研究成果比传统等效电路模型相比提高了精度,且计算量比P2D(Pseudotwo-dimensions,P2D)模型小,预期可以用于BMS中电池模型可用功率的在线仿真计算,避免动力电池过功率放电,提高电动自行车使用安全性。With the advancement of energy transition in China,using power batteries is rising yearly.The problem of battery safety has gradually come to the fore.In the battery management system(BMS),the equivalent circuit model(ECM)is the core of its work to ensure safe and stable operation.The current battery model in the BMS is mainly linear,which is limited by the computational volume and the computing power of the chip,which cannot reasonably and practically express the nonlinear characteristics of the battery under extreme operating conditions,such as high power.To address this problem,herein,from the perspective of available power,pulse discharge experiments are conducted on the battery at different multipliers to analyze the nonlinear characteristics of the internal resistance of the battery,improve the equivalent circuit model of the battery,and establish the variation of impedance with current under high multiplier conditions.The error of the improved impedance model is 1.74%,considerably smaller than the 8%of the old model.The results show an improved accuracy compared with the traditional equivalent circuit model,and the calculated computational volume is smaller than that of the P2D model,which is expected to be used in the online simulation calculation of the battery model in BMS to avoid over-power discharge of power batteries and improve the safety of battery use.

关 键 词：锂离子电池 模型参数 电池阻抗 阻抗模型优化 倍率特性实验 主动管理 

分 类 号：TM911.3[电气工程—电力电子与电力传动]