Rhino 5s1p 4900mAh 20C Lipo Problem

[suicideneil]

I think he was joking... ...at least I hope he was.

Anyways Finnster, 4s = 18v because you only charge the cells upto 3.6v each, then stop the charge & restart it with the charger set for a 5s pack to achieve the full 4.2v per cell. Its a safety feature in many chargers- you plug in a pack, and if the voltage isnt high enough for the pack vs what you've told the charger it should be, then it will assume you're thick and charge the pack as though it were 1 cell smaller. Kind of annoying, but it does save people from tryign to charge a 2s pack as a 3s etc and burning down their house....

[Finnster]

Originally Posted by suicideneil

I think he was joking... ...at least I hope he was.

Anyways Finnster, 4s = 18v because you only charge the cells upto 3.6v each, then stop the charge & restart it with the charger set for a 5s pack to achieve the full 4.2v per cell. Its a safety feature in many chargers- you plug in a pack, and if the voltage isnt high enough for the pack vs what you've told the charger it should be, then it will assume you're thick and charge the pack as though it were 1 cell smaller. Kind of annoying, but it does save people from tryign to charge a 2s pack as a 3s etc and burning down their house....

I thought that's what you were saying, but it didn't quite make sense as written. Most of the chargers I have ask you to confirm the higher cell count.

I'm still confused on your math tho, 18V/5=3.6V, 18/4=4.5. 4S=18v?
If I am understanding you, you say charge as a 4S to 3.6V/cell, then stop, then charge as a 5S. Full charge on 5S gets you to 21V.

Originally Posted by suicideneil

There is a very simple trick you can perform; charge the lipo as a 4s pack until the voltage of each cell is at the nominal level or just over- thats 3.6v each, so the total voltage will be 18v. Now, stop the charge and restart it- the charger should recognize that you have a 5 cell pack and ask you to confirm this before it starts the charge.

If you are charging a 4S pack to 3.6, then stopping, that only gets you to 14.4V. It will still "think" is a 4S pack. That's still less than 3v/cell for a 5S anyway, which is bad to begin with. If you do a 4S full charge, you can get upto 16.8, but as said, I would stop mine @ ~16.5V as it goes into CV mode and the amps slow down alot.
(This was done on a charger that would only trickle charge until voltage got over like 3.3V/cell, annoying as hell. I'd cheat it up to 16.xV faster, then go to 5S mode. I wouldn't do this unless forced to tho, that charger was dumb like that.)