Battery Life Extending Charging Strategy for Plug-in Hybrid Electric Vehicles and Battery Electric Vehicles*

This paper presents an optimal control based charging strategy for plug-in hybrid electric vehicles (PHEVs) and battery electric vehicles (BEVs). This work proposes a method to minimize battery capacity degradation incurred during charging by optimizing current profile. A semi-empirical battery aging model is adopted to quantify the capacity loss; a generic control-oriented vehicle cabin thermal model is developed to describe the battery surroundings taking into account solar radiation. Optimal control solution offered by Pontryagin’s Minimum Principle (PMP) is presented. Simulation-based results show that the benefit of this strategy in terms of decreasing battery aging is significant, when compared with the existing strategies, such as the widely accepted constant current constant voltage (CC-CV) protocol.