论文标题
锂离子电池模型参数化的非线性电化学阻抗光谱
Nonlinear electrochemical impedance spectroscopy for lithium-ion battery model parameterization
论文作者
论文摘要
在这项工作中,我们分析了锂离子电池的局部非线性电化学阻抗光谱(NLEIS)响应,并根据测得的NLEIS数据估算模型参数。该分析假设一个单粒子模型,包括电极颗粒内锂的非线性扩散以及表面不对称电荷转移动力学。基于此模型并假设中等曲折的激发幅度,我们系统地得出了在第二次谐波响应之前的阻抗分析公式,从而使每个贡献的有意义的解释在模型中的物理过程和非线性方面都可以做出有意义的解释。探索了此对参数化的影响,包括使用最大似然的结构可识别性分析和参数估计,以及合成和实验测量的阻抗数据。可以准确地拟合阻抗数据,但是拟合扩散时间表中的不一致表明非线性扩散模型可能不适合所考虑的单元。还通过使用参数化模型来预测时间域电压响应来证明模型验证,这证明与测量的电压时间序列数据(11.1 mV RMSE)具有极好的一致性。
In this work we analyse the local nonlinear electrochemical impedance spectroscopy (NLEIS) response of a lithium-ion battery and estimate model parameters from measured NLEIS data. The analysis assumes a single-particle model including nonlinear diffusion of lithium within the electrode particles and asymmetric charge transfer kinetics at their surface. Based on this model and assuming a moderately-small excitation amplitude, we systematically derive analytical formulae for the impedances up to the second harmonic response, allowing the meaningful interpretation of each contribution in terms of physical processes and nonlinearities in the model. The implications of this for parameterization are explored, including structural identifiability analysis and parameter estimation using maximum likelihood, with both synthetic and experimentally measured impedance data. Accurate fits to impedance data are possible, however inconsistencies in the fitted diffusion timescales suggest that a nonlinear diffusion model may not be appropriate for the cells considered. Model validation is also demonstrated by predicting time-domain voltage response using the parameterized model and this is shown to have excellent agreement with measured voltage time-series data (11.1 mV RMSE).