All the components work at 5V, less the motors and motor drivers that work as much at 10.8V(if I pass this limit, the motor drives burns itself).Yes, and/or use battery voltage whenever possible so you don't waste as much power in voltage regulators.
What is the voltage tolerance of the components being used? What is the current capacity of the battery you're using (is it a 9V transistor radio battery)? How much runtime do you want?
Actually I'm using normal batteries of 1.5V, but I will use lithium-ion batteries. I want to connect two 3.7V lithium-ion batteries serial, but maybe I will need to connect more in parallel to get more amperage.
I would like between 30 minutes and 1h of runtime.