hi
how to charge single celled lipos ?
will mobile charger work?
anyone have experience with it ?

the idea of charging using mobile charger was proposed by me lol

yaa..
but i was the first to post

well folks this topic was put up when we two were talking of 1 cell lipo as i asked him to buy for me

actually i have charged many types of batteries including ni-mh , ni-cd , li-ion [of mobiles] all barely- by just using that charger and they work fine

but i don't know the results of it on lipo

The mobile chargers usually give out a little over 5V. The actual charger chip is inside your phone. So no, you cannot just plugin a LiPo.

Building a single cell LiPo charger is quite easy if you can do soldering. There are no balancing issues, so the circuit for a current and voltage limited charger is very simple and cheap.

Do you have any recommendations for such a circuit with parts that are easily available locally ?

i cAN do soldering tell me the circuit

See page 20 "current limited voltage regulator" and current limited 6V charger on page 22 of LM317 datasheet. Read this datasheet for the details of the regulator IC. You need to set the output voltage to 4.2V and current to 1C value of of your battery.

Adaptation of this circuit with component values for LiPo cells has been popularised by http://shdesigns.org/lionchg.html in RC world. You can pick up the circuit from here if you don't want to do the calculations yourself.

Since you are going to use a mobile charger with about 5V output, there is not enough headroom for dropout voltage of LM317. You could substitute LM2940 in place of LM317 for your application.

any thing simpler than it which requires less things-something simple availble?

and i have a charger that outputs 4.5v at 600mah

is that charger ok?

Quoteis that charger ok?

No. You will need at least 6V at the rated current (1C) of your LiPo.

Don't try experiments with LiPo, overcharging can result in fire.

It doesn't really get simpler than the first circuit http://shdesigns.org/pdf/lionchg.pdf. If that is challenging, you have to look at buying.

can u tell me where to buy one?

Quote from: sushil_anand on December 03, 2009, 04:36:10 PM
No. You will need at least 6V at the rated current (1C) of your LiPo.

Since the mah rating of the lipo was not mentioned, how was this calculation done ?

http://www.funnhobby.com/showdetails.aspx?id=1152

is this charger ok

The page does not display well, but it says the output is 8v or 12v.  So that would work for two cell or three cell lipos. 

You were after single cell chargers, right ?

Quote from: sushil_anand on December 03, 2009, 04:36:10 PM

Quoteis that charger ok?

No. You will need at least 6V at the rated current (1C) of your LiPo.

ya i was over charging 1cell lipo only but read the post above to understand my intentions

Quote from: ankurgr8on on December 04, 2009, 04:43:02 PM
ya i was over charging 1cell lipo only but read the post above to understand my intentions

Which post ? Anyways, this does not look like a good match for one cell lipo charging.

then tell other possibilities other than those given by rotorzone

Just curious, what are you guys planning to do with the one cell lipo ?  Almost all routine use of lipos in the RC world happens on two cell lipos or higher, so this is most interesting 

TO BE USED ON SMALL PLANES WITH BRUSHED MOTORS THUS MAKING IT VERY CHEAP

Well,Anwar bahiya i expected that u used small electric  helis which run on these batteries and thus should be able to answer this question

Hmmm..  they are borderline, more like toys 

And they come with their own charger, did you lose yours ? Single cell chargers are harder to find, precisely for the reason I mentioned (they are not common in the RC world). 

For example, if you are willing to pay Rs550 for a charger, why not spend a little more, and get another toy heli or toy plane ?

Of course they are available...

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWLT6 (expensive)
http://www.rcgroups.com/forums/showthread.php?t=1116487 (some cheap options)

If you absolutely do not want to build your own based on the plan Rajesh posted (which seems to be a widely used option), eBay sounds like your best route.

Actually Amir bhaiya has order multiple lipos [single cell] for me-they are of two tpyes with different 'mah'
ask him the 'mah' of the batteries and tell us the charger for them[better if its is 1 or cheap two of them]

Rajesh - What would be a best guess on the total cost of building that first circuit you posted using locally available components ?