I thought the BMS did that but wasn't sure.

I know the battery for my bike outputs at 36 volt but there is nothing on it to indicate the manufacturer or other output details.

The batteries I was thinking of trying are listed as follows: 3 x NEW 12V 10AH Mobility Scooter/Electric Bike Batteries.

They are listed at a good price and are relatively close to me.

Your further comments would be appreciated.