Bosch e-bike - are the motors locked to the battery/control?

[PhillipM]

Bit of a weird question for here I know but some might know - I have a bike with a bosch mid-drive motor, but no battery, and no controller.
The intent was just to buy a controller and then knock together a battery out of spare parts I have - however, someone I know that dabbles with e-bikes told me the Bosch stuff has a control line to the battery and controller - and won't work without the genuine parts and original controller that was for the bike?

Anyone know if that's right or just whispers being passed along - as I can't see anything like that in any info when I looked.