Optimum operation on electric vehicles considering battery degradation in V2G system

In vehicle-to-grid system (V2G), a great number of electric vehicles (EVs) can form a massive energy storage to perform the operation of charging, discharging and providing frequency regulation for the grid. This process may lead to battery degradation of the EVs. In this paper, we propose to optimize the operation of EVs in each hour to maximize the user's total revenue, where Lithium battery is used for the EVs and the battery degradation is considered. Here, battery degradation includes two parts, one is the degradation caused by battery temperature during EVs' charging and discharging; another is the degradation caused by the depth of discharge (DoD). Considering the real-time electricity price, the optimum operation of each hour, i.e., charging, discharging or frequency regulation, can be obtained by V2G control center. Simulation results are provided to demonstrate that an optimum operation in each hour can be obtained to maximize the users profit. It also shows that large charging or discharging rate, and DoD reduces the battery's capacity and life cycle, which finally leads to the loss of user's benefit.