The charging and discharging activities of electric vehicles（EV）can exert significant effects on the safety and economy of power system operation.This paper first compares and analyzes three most common EV battery charging modes.Then，based on the time-of-use（TOU）pricing mechanism，the operation and arbitration modes of electric vehicle battery swapping stations（EVBSS）are analyzed，and the benefit function of the EVBSS is proposed.Then，based on definite simplified on assumptions，taking the maximum operating income of EVBSS as the objective function，a linear programming model for EVBSS optimal charge/discharge strategy is established and solved.Finally，it is verified at two different energy pricings.Case study shows that the optimization model proposed is simple and effective.The work of this paper can help EVBSS operators gain maximum economic benefits and give evidence for grid management departments on EVBSS management and dispatching.