Hi hi hello
i have some 2s 7400mAh 90c batteries that when I recharge them the charger puts back in about 3800-4400mAh 5-7min run on a 4.5t 7600kv motor

I was thinking of dropping to a lower turn motor 4000kv or 6100kv an using,
3s 4500mAh 90c save weight
or
3s 5400mAh 90c

My question is will I run out of mAh (over discharge) in the same 5-7mins? Using either of these batteribatterie

Thanks
Dre

3 cells on 4500kv enjoy the short life of that esc and motor.
you will run outa something in that time...lol

The math is simple......

To run a same performance you need to have a same power. With a 2S to 3S battery that is a 1.5 factor with the voltage. Because power = made by voltage x current so you do need a 1.5x lower current, and to get the same runtime also a 1.5x lower capacity. To be honest, a 3S hardcased battery can just store a 1.5x smaller capacity.

Then there are other factors. Yes, on 3S you have lower currents which gives less loss on wires, solder joints and connectors.but the 3rd cell has a higher battery resistance. So at the end the efficiency of the motor, ESC and maybe battery will make the difference.

Ok thanks, got an idea of what I need