New battery new head speed?

[WyDiablo]

I was running a stock battery (1800Mah) in my blade 400 until now. I got a new 2100 Mah battery and charged it with my charger and balancer. Yesterday I flew it with the 1800 frrst and the head speed seemed ok as usual. After the 1800 ran down I put the 2100 in the heli and I had probably twice the head speed than I had with the first battery. At first I thought that my "Idle up" was flipped on but it was off. The head speed was unreal for the heli. But also the battery did not last very long iether. Any thoughts or suggestions?

Thanks
WyDiablo

[skigolfmike]

It's simple. Power (Watts) = Amps times Voltage. With better batteries the head speed will be higher because the voltage drop is less due to the internal resistance of the battery being lower.

For the headspeed to be doubled, you'd need to put on a 6S battery pack. More than likely you'd burn up the ESC and at those kind of head speeds, the head would just explode. You probably picked up 200 rpm, which can sound like a lot.

What is the battery?

[WyDiablo]

I'm using a E-Flite 2100 maH 3s 11.1v 20c Lipo 13 GA ES3 Battery

[skigolfmike]

K - doing a little math 20C * 1.8Ah = 36A, 20C * 2.1Ah = 42A. Your not going to pull more than 25A with the stock motor and not more than 12-13A hovering. So why the difference when both batteries are capable of putting out way more than the power system is capable of drawing?

2 reasons. First the internal resistance of the larger capacity battery is lower, so the voltage loss in the battery under load is less. Secondly, your other battery is not new, so, depending on the number of cycles and how deep you discharged the battery each time, may not be as good as it was when it was new.

I got 2 stock batteries initially. Then I got 2 TP 2100 ProLites. They are only 15C, but right off the bat they had 200RPM more than the E-Flite 1800 20C. E-Flite's 20C is pretty weak IMHO.

[WyDiablo]

Thanks for the good info. I'll try and digest as much as I can lol thanks man

[Mon_t]

Originally Posted by skigolfmike

K - doing a little math 20C * 1.8Ah = 36A, 20C * 2.1Ah = 42A. Your not going to pull more than 25A with the stock motor and not more than 12-13A hovering. So why the difference when both batteries are capable of putting out way more than the power system is capable of drawing?

2 reasons. First the internal resistance of the larger capacity battery is lower, so the voltage loss in the battery under load is less. Secondly, your other battery is not new, so, depending on the number of cycles and how deep you discharged the battery each time, may not be as good as it was when it was new.

I got 2 stock batteries initially. Then I got 2 TP 2100 ProLites. They are only 15C, but right off the bat they had 200RPM more than the E-Flite 1800 20C. E-Flite's 20C is pretty weak IMHO.

Mike, the speedy is only rated for 25A you'll find that you can put more than that through it especially under high load, it has a burst value just like your batteries, (not that I've been able to reach that). It is possible to draw enough current to cook the ESC.