What is controller "Battery Choose" for?

In a file for my controller it says "Battery Choose" for terminal 15 in the big connector with room for 30 wires.
The terminal is unused on my scooter (there is no wire) but i would like to know what it is for.

It sound like the controller might be able to switch between batteries.
Like if the scooter have 2 batteries maybe i could switch between by pressing a switch and not having to move the battery cable(s).
Or maybe it could be for choosing if the battery is lead-acid or lithium or something else.

Have anyone seen a scooter with a switch or something that might use "Battery Choose"?
Its properly translated from chinese to english so maybe the wording "Battery Choose" is not perfect.