Strategies for competing energy storage technologies for in DC fast charging stations

The universal acceptance of electric vehicles depends on the widespread presence of charging stations. These stations have to be designed intelligently so as not to overwhelm the fragile power grid with the additional load. In this paper we extend our previous work in [1] and examine how the charging station performance, namely the blocking probability, is affected both by the energy storage technology used, and the employed charging strategy. We consider two strategies: charging from the energy storage first, and charging from the power grid first. We compare their performance for different sets of system parameters and identify the optimum operating rule. Finally, we describe an economic model, which allows us to determine the trade-offs involved when choosing between an energy storage with higher capacity or one with a higher power rating.