Hybrid electric vehicle supervisory control design reflecting estimated lithium-ion battery electrochemical dynamics

Accurate prediction of the battery electrochemical dynamics is important to avoid undesired battery operation under aggressive driving. This paper proposes a battery power management strategy considering Li-ion concentration in the electrodes to prevent excessive battery charging and discharging. The proposed approach adjusts the allowable battery power limits through the feedback of the estimated electrode-averaged Li-ion concentration information. An advanced hybrid electric vehicle (HEV) power split strategy is constructed implementing a Li-ion battery model with electrochemical diffusion dynamics to capture the battery dynamic behavior under transients. A novel contribution arises from the implementation of an extended Kalman filter (EKF) using uneven discretization of the particle radius for fast and accurate prediction of the Lithium intercalation dynamics. The control design modifies the allowable battery power limit used in the supervisory controller, thus, maintaining low complexity of the control structure.