Battery drop voltage

[dxer]

So I have several batteries for my H , each maybe 10-13 times charged.
They are charged to 16.7 V but what bothers me is that after just one minute of flight , voltage is droopped to like 16 V or even slightly lower.

Is this normal ?

Today there was a slight wind and I flew to 14.6 V , no more than 15 minutes. After powering down motors it went to 15 V. So is this OK, we don't have actually more than maybe 16 minutes of flight ?
I mean hovering would be probably go to 20 or more.

Anyway, as I underatand 15 V is storage voltage OK, right ?
Is it better to have chargers like SkyRC for the longterm of using batteries ?

 

[Steve Carr]

So I have several batteries for my H , each maybe 10-13 times charged.
They are charged to 16.7 V but what bothers me is that after just one minute of flight , voltage is droopped to like 16 V or even slightly lower.

Is this normal ?

Today there was a slight wind and I flew to 14.6 V , no more than 15 minutes. After powering down motors it went to 15 V. So is this OK, we don't have actually more than maybe 16 minutes of flight ?
I mean hovering would be probably go to 20 or more.

Anyway, as I underatand 15 V is storage voltage OK, right ?
Is it better to have chargers like SkyRC for the longterm of using batteries ?

15v is fine for storage. The recommended voltage is 3.7 volts per cell which would be 14.8v. Close enough.
The battery voltage will always rebound after you shut off the motors. Dropping voltage during flight is normal. Mine do the same. Wind and rapid climbing cause the voltage to drop very fast. You could continue to fly until the low voltage warning, but I don't recommend that. It will probably shorten the battery life.

 

[prathbun]

This is a big topic, and each of your questions falls into more than one category...

A lot depends on the temperature of your batteries in addition to their overall health; and how hard you're flying. With gentle flying (and warm batteries) I get around 15-18 minutes on a 6700 mAh pack.

That initial drop is pretty normal. Here's a 12-minute flight in cool (45°F) weather. See the big drop at the start, then it flattens out, then jumps back up when it's landed.



Here's one this morning with a really cold (+/- 35°F) battery (about 30 seconds aloft before the warning).

 

[Steve Carr]

Perfect.

 

[dxer]

Thanks for clearing this up.

What about better charger ? Would this be better for the life of the battery ?

 

[Steve Carr]

Thanks for clearing this up.

What about better charger ? Would this be better for the life of the battery ?

It certainly doesn't hurt to use a better charger. I have to say, however, I have been using the original for 8 months with no problem. I have the kit to make the cables and I have several chargers. I just haven't done it yet.

 

[prathbun]

Thanks for clearing this up.

What about better charger ? Would this be better for the life of the battery ?

Depends on the turn-around time you're looking for and the batteries you're using. The stock charger doesn't work well for me because I (try to) do several flights a day on four batteries, and it just takes too long. Also it doesn't have the ability to look at individual cell voltages, internal resistance, increased charge-rate, etc. You'll get as many opinions on the best charger as there are people posting here ;-) I use a Venom Pro Duo and an older Venom Medion, which gives me four simultaneous charges and all the diagnostics I need.

 

[dxer]

Ok, so this third party chargers are showing all these things.....but how is this actually helping us to better charge battery ?
I mean, can we influence on these features if we see that individual cells are not charged correctly or this is just for us to monitor charge process ?

I see there are this small balancer devices to purchase too. Are these necessary to have too, with this chargers as SkyRC D100 for example or this Venom ?
Or these chargers will do everything we need ?