Experimental validation of adaptive observers for battery management systems

A lithium ion battery model includes several parametric uncertainties, which need to be identified in real time in order to determine accurate estimates of State of Charge (SOC) and State of Health. Recently, an augmented adaptive observer that simultaneously estimates the parameters of the underlying linear dynamics and algebraic nonlinearities in a modified Single Particle Model (SPM) was proposed. In this paper, we validate this observer experimentally using a Panasonic cell. The algebraic nonlinearities included are both due to open circuit potential and due to over potential. Using the properties of these potential functions and experimental constraints, a novel adaptive observer was used to estimate their parameters as well as those of the underlying linear dynamics. The experimental results show that the adaptive observer results in accurate SOC estimation and parameter convergence.