With the rapid development of EVs (electric vehicles), the integration of PV (photovoltaic) generation with EV charging infrastructure can effectively improve the efficiency of clean energy utilization and carbon emission reduction. How to optimize the capacities of components in the PV-based BSS (battery switch stations) is still unsettled. This paper focuses on the mathematical model of the problem. With consideration of battery swapping requirement and maximally utilizing PV energy, an energy exchange strategy is introduced for the PV-based BSS, including battery swapping service model and power distribution model. Towards benefits of economy and environment, objective functions of capacity optimization are modeled with the purpose of minimizing annual cost and maximizing the percentage of utilized PV energy in total energy. The constraints include the construction scale, power balance and battery swapping service etc. Based on the energy exchange strategy, the optimization model is solved by NSGA-II algorithm. Finally, taking the planning of a PV-based BSS in a certain district as example, optimized capacities of PV panels, EV batteries, EV chargers and grid-connected modules can be obtained. From the analysis of the results, the method can provide a foundation for the plan and design of the PV-based BSSs. (C) 2013 Elsevier Ltd. All rights reserved.