helicub81

Hmm, so i recently purchased this charger: http://www.valuehobby.com/product_de...13&item_id=171. I know its cheap and probably won't last too long, but tts the first charger that i purchased. All of my other ones came with rtf packages. So i'm charging a 1300 mah 3 cell battery and i've charged the battery for three hours and the lights still haven't turned green. I emailed the support at valuehobby and "Alex" said that i should just pull the battery out after an hour or so even if the lights are still red. He said that the charger is probably just trying to balance the cells. Is this a good way to charge the battery? Will it wear out the battery?

I also tried charging the battery with an eflite charger that came with an rtf package and the battery balances fine with that.

azrcfly

Well, even with the worlds worst charger, it should not take nearly 3 hours to charge a 1300 3s, more like an 1 1/2 hour. I would keep an eye on the battery if it keeps going that long.

helicub81

hm, so should i just pull out the battery after 1.5 hours? The charger charges at at 1.2 amps, so in theory, it should completely charge in about one hour.

fmw

The problem could well be the battery. It sounds like your charger doesn't provide voltage readings. What you need to do is to get one of the cheap little voltmeters that plug into the balance plug of your battery. They will give you the voltage of each cell individually and then a total. They cost about $10 on Ebay.

helicub81

how would i measure the individual voltages of the cells with the voltmeter? Would i have to take apart the battery or something? Also, i know that the cells idividual voltage are supposed to be 4.2v. So, if the individual cells are about 4.2, does that mean the battery would be fully charged? Should i charge the battery in that manner?

Well, if i pull out the battery after 1.5 hours of chargig and plug it into an eflite charger that came in an rtf package, the charger idndicates that the battery is balaced in about 15 minutes (after the 1.5 hour charge). Am i correct to assume that the batteyr is not the issue?

fmw

By using the voltmeter I recommended. Something like this
http://cgi.ebay.com/RC-Lipo-battery-...item3efc474c78

I don't know that there is anything wrong with your battery. I simply suggested a means to find out.

helicub81

Ok, so i picked up a multimeter from lowes and basically, the individual cells are about 4.2 4.2 and 3.9 when fully charged. When discharged, it is 3.9 3.9 and 2.8. I'm thinking that means a bad battery?

fmw

That's what it looks like. You have a weak cell that won't come up to full charge and which discharges significantly faster than the others. It may perfectly useable if you don't discharge the weak one any more than you did. Under 3 volts the cells can change chemically and there is no going back if that happens.

Rodney

Can you charge just the weaker cell as a single cell using the balance connector? If so, charge that weak cell individually until it is the same voltage as the two good cells.

helicub81

hm, how would I be able to charge 1 cell? Would i attach the leads to that part of the balance charger or something? I have a stock 2-3 cell balance charger btw...