Bidirectional Conductive Charging of Electric Vehicles for V2V Energy Exchange

Battery-powered Electric Vehicles (EVs) are considered as an effective solution to curb carbon emissions and fight global warming. One of the main drawbacks in driving an EV is range anxiety, which can be defined as the fear of vehicle having insufficient range to reach its destination due to lack of charging. Vehicle-to-vehicle (V2V) charging is being explored as a solution to mitigate the range anxiety issue. V2V charging allows the sharing of charge between two EVs so that if an EV is stranded far from a charging station, it can be charged from another EV. Various V2V chargers have been studied. It has been found that the traditional chargers involve many power conversion stages, which reduces the efficiency in the energy exchange. In this paper, an off-board DC V2V charger is presented. It reduces the power conversion stages while dispensing with the use of any on-board charger. To implement the off-board DC V2V charger, a bidirectional DC-DC converter is adopted. The converter operates in various modes, depending upon voltage and state of charge of the EV batteries. In turn, the V2V charging is managed in an automatic way. Operation modes and management program of the off-board V2V charger are discussed in the paper.