Control-oriented modeling and adaptive parameter estimation of a Lithium ion intercalation cell

Battery management systems using parameter and state estimators, based on electrochemical models for Lithium ion cells, are promising efficient use and safety of the battery. A new reduced order model of the Pseudo Two-Dimensional model is derived, based on the absolute nodal coordinate formulation (ANCF). The ANCF model is shown to be accurate for currents up to 4C for a LiCoO2/LiC6 cell. To estimate SOC and SOH of the cell, an extended adaptive observer, guaranteeing global stability for state tracking, is presented. It is applied to the new reduced order model and parameters are shown to converge under conditions of persistent excitation.