I have a charger for my rc plane, and it needs an input of 11.5v-13.5v dc, and 1.5 amps. I went to radioshack and the wall adapter is 30, which is what i paid for the damn charger. Anyways, i have one here that is 5v dc and 1 amp. The said device that needs power is a balance charger, and I am going to be charging a 11.1v 2800 mah Lipo battery. It is supposed to charge the battery at 12.6v and 800mah. Also, i wouldn't mine charging it via the car, i have a ciggy lighter adapter, and an extra pigtail that came with the charger, so that wiring would be easy enough, im not sure how many amps the lighter puts out though. Anyways, would my wall adapter have enough juice to charge my battery,(the more i think about it, the less i think it will work) and how much longer would it take? If you just tell me the formula, or guide me the right direction, i could do the math. Thanks.

Edit, i just found a 10v 800mah one i could hack up too.

 

So the charger needs 11.5 to 13.5v and the supply you have puts out 5v? It wont work...

Or do I miss understand?

 

Yeah i figured it would only charge up to 5 volts.

 

I would imagine it would mess with the charger / the charger wouldn't even have enough voltage to run, and seeing how Li-po batteries are very sensitive to being charged wrong, I would not try it.

 

There's no way your 5V supply or 10V supply would get the job done; you need at least the 11.5V the manual calls for, it's pretty much specifiying a 12Vdc source.
You have three options:
1. Buy a 12Vdc, 1.5A wall adapter
2. Connect your charger to a 12V battery (like a car battery, they also have smaller gel cells you can get)
3. Wire up your car cigarette adapter, the fuse for that circuit should be ~10A, more than enough for what you need. That'll be the cheapest fix, since you already said you have the adapter. Center pin of the adapter is positive, the outside is negative - the connector for your charger is probably the same (center positive), but make sure first. Also, some of those cig adapters have a fuse in the tip; if so, you'll need to make sure that's > 1.5A.
Not really any equations you need to figure out what'll work, just stay within the voltage specs and above the current spec.
I'm (almost) an electronic engineer, and I play with LiPo planes too so I know what's going on. Lemme know if you need clarification on anything.

 

Dont mess around with what it needs. Search ebay. Whats wrong with the one you have now? I had a laptop adapter that got messed up, so I bought one on ebay, the jackass sent the wrong one and told me it was better, so I took the parts off it I needed and fixed the old one I had.

 

Check ebay. A 12 volt ac adapter at 1.5 amps is a VERY common size. In fact I'll look......

http://cgi.ebay.com/AC-100-240V-Conv...#ht_2132wt_911

Done. $7 and it will be there in about a week and a half from hong kong. VERY good chance it is the same thing that radio shack sells.

Also you might try the salvation army/thrift store's. I used to have one near me in Seattle that had a PILE of these things for a dollar a pop. So long as you know the volts/amps they are all the same inside. Just add the end you need.

 

charge an 11.1v LiPo with 5v, and you're actually going to discharge the battery. Best case scenario, it will cause irreversible damage. Worst case scenario, your LiPo will literally explode.

My first ever youtube embed attempt:


Get a real man's charger
http://www.maxamps.com/EOS0606i-AC-DC.htm

12-14V DC / 100-240V AC input. Balance 2s-6s

 

I just didn't feel like waiting on it. I wont try that other one. I was thinking that since it was 3.7v per cell..... but then i reasoned it out. I will just wait on the one from ebay. Being lazy, impatient, and cheap all at the same time is tough.