Originally Posted by Hoese37

Not quite true. Depends how the motor was rated. It could be much more if the motor was tested with no-load, as a lot of them are.



Plugging 8.4 in will help you a bit because the voltage starts out at this level. The higher the voltage, the lower the amperage when there is no change in load.

Originally Posted by cokemaster

Motors rating in wattage is what they can handle with full load continuously (nominal). Obviously, we will not have this continues load when we drive the car, since we coast, break and accelerate. During peak conditions like under full acceleration of your car, the ESC will see a much higher current (amps) during these conditions (up to 5 times the nominal) and ESC are designed to handle these currents for short periods (bursts). And yes, you can narrow down the size of an ESC with a simple calculation based on the nominal wattage and voltage. Lower voltage means higher current (power = voltage x current). I would use 7,2V, since I never go below 3,6V per cell. So, for a Novak 13.5T with 195W nominal power, the max amps continuously would be 27A. So you could getaway with a smaller ESC, e.g. 40A.

Another aspect is the capacity and C rating of the battery. The capacity is given in mAh, thus a 5000 mAh battery could theoretically supply 5000mA (5A) for 1 hour. With a rating of let's say 40C, it should be able to supply up to 40 x 5A = 200A. High C ratings is never needed, and I will actually make a statement that you would probably be more consistent with lower C rating (20-40C). The picture of the voltage drop given by "murat61" is a test of different batteries with a 98 Amps continuously load. It's a good indication of how voltage drops over time for Lipo batteries. The purple curve (5000mAh battery) is most likely drained 100%, but a good thumb rule is not to use more than 80% of your capacity.