D. Pavković, A. Komljenović, M. Hrgetić, M. Krznar

Experimental Characterization and Development of a SoC/SoH Estimator for a LiFePO4 Battery Cell

Proceedings of IEEE EUROCON 2015, Salamanca, Spain, 2015.
This paper presents the results of experimental characterization of an automotive LiFePO4 battery cell for the purpose of building of a control-oriented battery equivalent electrical circuit model suitable for designing a combined state-of-charge (SoC) and state-of-health (SoH) estimator. The SoC/SoH estimator design has been based on the time-series representation of the battery model utilized within the extended Kalman filter (EKF) parameter estimator, with SoC reconstruction based on the known open-circuit voltage vs. discharged charge curve. In order to provide a consistent SoC estimate during low-excitation intervals, EKF-based estimation has been combined with a Coulomb (charge) counting approach. The effectiveness of the proposed SoC/SoH estimator has been verified by means of computer simulations on the developed battery model for different battery operating regimes.