— Lithium-ion batteries are the core of new plug-in hybrid-electrical vehicles (PHEV) as well as considered in many 2nd generation hybrid electric vehicles (HEV). In most cases the lithium-ion battery performances play an important role in the vehicle energy management. As consequence, battery modeling is one of the most important tasks for hybrid and electrical vehicles control. Full order electrochemical models have to be simplified in order to make them compatible with estimation algorithms embedded in a real-time on-board electronic control unit. The battery model simplification has to be carried out accurately in order to achieve maximum computational cost reduction while ensuring the best model performance and reaching an efficient system management. In this paper two different reduced order models, based on the electrochemical laws, are compared both with simulation results and with experimental data collected from a 10 Ah lithium-ion battery. The reduced order models chara...