Nonlinear lithium-ion diffusion dynamics conscious power management strategy in hybrid electric vehicles for battery downsizing

摘要

This paper proposes a battery power management strategy using the estimated lithium-ion concentration in the electrodes to prevent battery over-charging and over-discharging under aggressive driving conditions. Excessive battery operation is moderated by adjusting the allowable battery power limits through the feedback of information on the electrode-averaged lithium-ion concentration estimated by the extended Kalman filter. Uneven discretization of the radii of the solid electrode particles is used in the extended Kalman filter to reduce the computation effort. Safe battery operation with a relatively small size of the battery is possible with the proposed battery power management strategy by preventing extreme conditions, thus providing more flexibility for the development of robust and cost-effective hybrid electric vehicles.