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The battery electrodes are porous and have complicated microstructures due to irregular sizes and shapes of pores. Electrode design parameters like porosity, thickness, particle size, and conductivity can vary from one local area to another in one cell. Even under the normal operating current, some local areas may experience over-charge/over-discharge, extensive degradation, and rapid heat generation. These local events are not easy to observe or measure at onset and can eventually lead to catastrophic failure of the whole cell if no actions are taken. Battery design parameters are treated as constant values in many electrochemical battery models. However, the uncertainty of these parameters has an adverse effect on the longevity and safety of batteries. To prevent any catastrophic failure, a battery model is needed to predict any potential over-charge/over-discharge and rapid heat generation caused by internal uncertainty.

Many problems are associated with the large battery operation current, such as battery overheating, lithium plating, and mechanical structural instability of battery materials. All these problems may cause battery safety issues in fuel cell hybrid vehicles (FCHVs), e.g., battery explosions and thermal runaway have been reported and may cause public anxiety about FCHVs. Previous researches on FCHV power management strategy have focused on minimizing fuel consumption. But more attention needs to put on the battery current constraint for analysis of battery state of charge (SOC) and battery state of health (SOH). This research targets optimizing the FCHV battery pack operation within a safe current range through power management strategy to increase the safety of the battery pack while improving battery usage via SOC control. Battery SOH is also evaluated in the study.