I'm building a small electromobile. I was planning on using a car alternator as the motor, however I'm now looking into buying a 48V 500W BLDC motor.
The problem is I'm not really sure how to manage the difference in voltage between what the motor requires and the rest of my circuitry.
I have a bunch of components that run at 12V as well as another bunch at 5V. In the scenario where I have a 12V battery I just use a buck converter to step-down the voltage for my 5V circuit and it all seems fine since it didn't draw anywhere near the 3A maximum rating of the converter.
Now my 12V circuit draws ~10A at full load. If I have a 48V battery I think I'll have trouble using a buck converter for that purpose. I was thinking I could tap into a point between the battery cells where the voltage will be 12V but that is probably dangerous, I'm pretty sure difference in voltage in the cells will upset the battery.
What would be the "proper" way to power my 48V motor and 12V as well as 5V circuit?