基于PNGV电路模型的新能源汽车钴酸锂电池内阻研究

Research on Internal Resistance of Automobile Cobaltate Lithium-ion Battery Based on PNGV Circuit Model

对新能源汽车钴酸锂电池进行PNGV建模,依据可测的外部电压和电流来估算电池内部直接测量的欧姆内阻和极化内阻。实验采用混合脉冲功率特性法(HPPC)来获取锂电池在脉冲充放电和过渡过程中的各参数。最后基于Matlab/Simulink对电池的PNGV等效模型进行了可行性验证。实验表明,用HPPC实验测得的锂电池极化电阻Rp和欧姆内阻R0精度高,辨识方法正确。基于PNGV电路模型对汽车动力钴酸锂电池进行等效研究可行,该模型电压估算误差0.015 V,欧姆内阻与极化内阻最大误差分别为0.0728 mΩ和0.0696 mΩ。本实验结论可为钴酸锂电池的内阻估算提供理论依据。

The PNGV model of lithium cobalt battery for the new energy vehicle is modeled.The ohmic internal resistance and polarization internal resistance measured directly in the battery are estimated on the basis of the measured external voltage and current.HPPC was used to obtain the parameters of the lithium battery in the process of pulse charge discharge and transition.Finally,the feasibility of the PNGV equivalent model of the battery is verified based on Matlab/Simulink.The experimental results show that the polarization resistance Rp and ohmic resistance R0 of lithium battery measured by HPPC test are high,and the identification method is correct.Based on the PNGV circuit model,the equivalent study of automobile powered lithium cobalt lithium battery is feasible.The voltage estimation error of the model is 0.015 V,and the maximum error of Ohm internal resistance and polarization internal resistance is 0.0728 mΩand 0.0696 mΩrespectively.The experimental conclusion can provide theoretical basis for the estimation of internal resistance of lithium cobalt batteries.