Battery system, controlling method of the same, and energy storage system including the battery system

A battery system comprising:

• a rack having a plurality of battery tray positions, each of the battery tray positions being associated with position information;
• a battery tray in a corresponding battery tray position among the battery tray positions, the battery tray having an identifier;
• and
• a system management unit electrically coupled to the battery tray, and being configured to receive and store the position information and the identifier,
• wherein the system management unit is configured to determine the corresponding battery tray position of the battery tray in accordance with the identifier and the position information,
• further comprising:
• a plurality of position information boards respectively corresponding to the plurality of battery tray positions, each of the position information boards being configured to provide the position information of a corresponding one of the battery tray positions.