SOH Estimation of Lithium-ion Batteries for Electric Vehicles

Accurate estimates of the state-of-health (SOH) for rechargeable batteries provide a significant value to the management of any operation involving electrical systems. This is especially important for transportation systems, where unexpected battery performance may lead to catastrophic failures. This paper performs experiments aiming at analyzing Lithium-ion battery performances with aging due to different temperatures and charging-discharging rates, and the optimum working areas of temperature and charging-discharging current are determined. In addition, the cycle life tests of battery are launched based on the simulations of battery performances under typical urban driving cycles using ADVISOR, and after the inspection of the results, a new SOH prediction model is proposed. Finally, in comparison with the experimental results, it is shown that the proposed method could be valid and effective in estimating battery SOH.