I. Introduction
As an important means to reduce environmental pollution, the development of renewable energies (REs) and electric vehicles (EVs) promote each other [1], [2]. EVs are not only a load of the smart grid but also can be used as energy storage to increase the penetration of REs [3]. Lithium-ion batteries have become the main choice for EVs or other storage systems due to their many advantages [4]–[6]. In order to maximize the potential of the batteries, charging technologies have increasingly become one of the focuses [7], [8].