No one has mentioned a VESC, yet. It is an open source controller that is capable of 240A for a few seconds or about 50A continuous depending on cooling. 8V-60V range. You can configure amp limits and safe voltage cutoffs.
The ESC is rated up to 3S (~12V). 6V is the BEC or Battery Eliminator Circuit. The higher the voltage, the less current is needed. . In theory, a 10V 100A setup and a 48V 20A setup will perform the same (with appropriate gearing), as they are both ~1000W. In practice, higher currents are less...