Swap and Carry Strategy for Utilizing Spare Batteries as an Emergency Power Supply on Battery Swapping EV

Electric Vehicles (EVs) have attracted attention to reduce greenhouse gas. Battery swapping EVs make it possible to drive longer distance than plug-in charging EVs, because battery swapping EVs can swap batteries in a few minutes. However these services need a lot of initial costs to be distributed widely. One of the reasons is that a number of spare batteries need to be installed in Battery Swapping Stations (BSSs). Then we will propose to utilize spare batteries for other purposes except for driving EVs, like an emergency power supply at the time of disaster. For the purpose, spare batteries must be kept in a certain level. But batteries in a BSS which located in an overcrowded area tend to be low because the BSS is used frequently, and the batteries cannot supply enough power. Therefore, this paper focuses on the issues by battery transportation, and proposes a method that can equalize the amount of electricity levels of spare battery in BSS by transporting a battery from the BSS in which the average state of charge (SOC) of spare batteries is high to the one is low.