中文摘要：

电动汽车蓄电池成本占整车成本约三分之一,因此规模化应用之后,针对电动汽车换电站不同时段的蓄电池储备量及充电设备规模的优化研究对提高换电站建设运营的经济性及促进电动汽车的发展具有重大意义。提出了换电站蓄电池冗余度的概念,建立了基于一定用户换电需求和换电站充电管理策略下,换电站充电设备规模和蓄电池冗余度需求模型。应用蒙特卡洛（Monte Carlo）方法进行仿真计算,得出换电站不同充电设备规模下的储备蓄电池冗余度。算例分析表明,所提方法在充电设备规模增长初期可以大幅减少电池冗余度,达到相应规模之后还能提升可用于优化控制充电的蓄电池的数量和电量裕度。

英文摘要：

Electric vehicle （EV） battery cost accounts for about one third cost of EVs. After the large-scale application of EV, it is of great significance to study the scale of charging equipment and the number of fully charged batteries in a battery swapping station in different time intervals for economical operation of swapping station and development of EV. The concept of battery redundancy was given, and a mathematical model based on certain EV owners＇ swapping demand and charging management strategy was proposed. The method was simulated by Monte Carlo method to get the reserved battery redundancy at different scales of charging equipment. The calculation results show that the method can drastically reduce battery redundancy on the initial growth stage of charging equipment scale. After arriving at corresponding scale, it also can contribute to the growth of coordinated charging capacity.