Real-time Analysis of Battery Degradation in a Plug-in Hybrid Electric Vehicles during Vehicle-to-Grid Operation

This paper examines the effect of vehicle-to-grid (V2G) integration on battery aging and the economic viability of plug-in hybrid electric vehicles (PHEVs). Due to their energy storage potential, V2G technologies are considered an environmentally friendly means to increase the stability of power grids. Persistent V2G operations tend to reduce battery lifetime and, consequently, will increase its replacement cost, which is a source of uncertainty for EV owners. This work investigates battery degradation under two scenarios: first, under normal vehicle operation using the US06 drive cycle, and second, under V2G operation with a 10-kW and 15-kW bidirectional charger. In the case of V2G operation, the charger discharges the battery by 20 kWh and then recharges it back to 90% state of charge (SoC) at a constant 1C-rate. Real-time simulations are performed in order to validate these results: a grid, a bidirectional charger, and the vehicle battery are modeled in a real-time simulator; furthermore, a pair of controllers is used in order to run the energy management and predict the battery aging. Economic analysis assesses the capacity loss due to V2G participation as well as the incentives, providing a comprehensive view of the economic feasibility of V2G applications and their potential benefits.