Getting 12V out of 60V battery bank
Likely not a good idea as you would not have equal discharge from all cells in the bank.  This could (depending on how sophisticated and complex your charger is) cause trouble with charging.  It could also cause shortened pack run time and reduced pack life.  Depending on how the pack is constructed it could also impact some of the safety features.

You're better off with a buck converter that will take the 60V and convert it down to 12V.