The design of a lumped parameter battery model preserving physical meaning is especially desired by the automotive researchers and engineers due to the strong demand for battery system control, estimation, diagnosis and prognostics. In light of this, a novel simplified fractional order electrochemical model is developed for electric vehicle (EV) applications in this paper. In the model, a general fractional order transfer function is designed for the solid phase lithium ion diffusion approximation. The dynamic characteristics of the electrolyte concentration overpotential are approximated by a first-order resistance-capacitor transfer function in the electrolyte phase. The Ohmic resistances and electrochemical reaction kinetics resistance are simplified to a lumped Ohmic resistance parameter. Overall, the number of model parameters is reduced from 30 to 9, yet the accuracy of the model is still guaranteed. In order to address the dynamics of phase-change phenomenon in the active particle during charging and discharging, variable solid-state diffusivity is taken into consideration in the model. Also, the observability of the model is analyzed on two types of lithium ion batteries subsequently. Results show the fractional order model with variable solid-state diffusivity agrees very well with experimental data at various current input conditions and is suitable for electric vehicle applications.

由于对电池系统控制，估计，诊断和预测的强烈需求，汽车研究人员和工程师特别希望保留物理意义的集总参数电池模型的设计。有鉴于此，本文针对电动汽车（EV）应用开发了一种新颖的简化分数阶电化学模型。在模型中，为固相锂离子扩散近似设计了通用的分数阶传递函数。电解质浓度超电势的动态特性通过电解质相中的一阶电阻-电容传递函数来近似。欧姆电阻和电化学反应动力学电阻简化为集总欧姆电阻参数。全面的，模型参数的数量从30个减少到9个，但仍然可以保证模型的准确性。为了解决充电和放电过程中活性粒子中相变现象的动力学问题，模型中考虑了可变的固态扩散率。另外，随后在两种类型的锂离子电池上分析了模型的可观察性。结果表明，在各种电流输入条件下，具有可变固态扩散率的分数阶模型与实验数据非常吻合，适用于电动汽车应用。随后在两种类型的锂离子电池上分析了模型的可观察性。结果表明，在各种电流输入条件下，具有可变固态扩散率的分数阶模型与实验数据非常吻合，适用于电动汽车应用。随后在两种类型的锂离子电池上分析了模型的可观察性。结果表明，在各种电流输入条件下，具有可变固态扩散率的分数阶模型与实验数据非常吻合，适用于电动汽车应用。