A bin storage system includes a bin storage structure and robot vehicles for retrieving storage bins from the bin storage structure. The bin storage structure includes pillars that define storage columns for the storage bins, supporting rails, arranged on top of the pillars to provide a vehicle support for the plurality of robot vehicles allowing each robot vehicle to travel across the bin storage structure, a storage bin delivery station, and a bin lift device, arranged to receive storage bins from the plurality of robot vehicles and transport the storage bins from a top level of the bin storage structure to the delivery station. Each robot vehicle includes sets of rolling means for moving the robot vehicle along the supporting rails, a cavity for receiving a storage bin, and a lifting device for retrieving a storage bin from a storage column and storing the storage bin in the cavity.