I'm thinking it is the position it came out of. The tray they sit in have different locations given. I have tried to research it more but I've been busy.
I am told the BIN number is one of many pieces of information that needs to be on a worksheet required to order the battery in the first place. The BIN number is provided by the technician, obtained from GDS - so I am told.
See SI document ID#4868078 PIP4148S. 2. Using GDS2, access the Battery Energy Control Module (BECM) and look under the identification information section. The BIN will be listed under the parameter: Hybrid/EV Battery Pack Identification Number. As an alternate, locate the BIN on one of two tags on the battery pack itself. The BIN is the bottom most 16-digit code and begins with the letter “T”.