Vehicle and battery pack and method for controlling a battery pack assembly

There is provided a vehicle which can install a plurality of detachable battery packs that accommodates a rechargeable battery module and a battery management system (BMS) in a case. In a state where the battery pack is installed in the vehicle, the BMS can perform information communication with another BMS, and one BMS is a master and can communicate with another BMS which is a slave and combine information of another battery pack. In a state where the battery pack is detached from the vehicle, a control of a charging state is independently performed by the BMS with respect to the rechargeable battery module.