modding batteries

OT: should have put this message elsewhere: how can I move it?

Hi all!

i was wondering if i could connect two other wires to this battery (http://www.sparkfun.com/commerce/product_info.php?products_id=731); it's a Polymer Lithium Ion. My idea is to have the two defaut wires to costantly charge my arduino board, and two more (added by myself) to end with a plug for a wall charger. So the custom-made battery would have four wires: two black and two red: allowing it to give energy to the arduino and to take energy from a wall (i was thinking to something like this http://www.sparkfun.com/commerce/product_info.php?products_id=8734). Do you think it's possible? ;-)

thanks much

batteries are touchy enough, lipo's can be bombs

I dont have any good or safe advice to give you, other then I don't advise it

That battery is 3.7V. IIRC the Arduino requires either 5V from the USB port or 7V from a wall adapter. Not sure how were planning on wiring it.

(* jcl *)

@Osgeld ahah, thanks for the advise! i just discovered that the arduino lilypad liPower which i have (http://www.sparkfun.com/commerce/product_info.php?products_id=8786) does have "terminals for charging an attached LiPo battery with one LiPo chargers." roll over "C", bottom left: http://www.flickr.com/photos/leahbuechley/2845764065/ . so it should be doable without any hack/mod. I'm safe! But now...how I do I connect it? _ anyway, thanks much for the quick reply!

Whatever you do, make sure you use the proper li-po charger; these batteries deliver tremendous power for their small size. As Osgeld noted, they can become "bombs" if improperly charged (or shorted, for that matter). There are more than a few videos on YouTube showing what can happen with such batteries (I tend to wonder how many homes of R/C modelers have burned down due to improper charging of these kinds of batteries)...

Be careful, and good luck!