modding batteries

Forum 2005-2010 (read only) Hardware Troubleshooting
1

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 (Lithium Ion Battery - 110mAh - PRT-13853 - SparkFun Electronics);
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 Barrel Jack to 2-pin JST - TOL-08734 - SparkFun Electronics).
Do you think it's possible? :wink:

thanks much

2

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

3

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 *)

4

@Osgeld
ahah, thanks for the advise!
i just discovered that the arduino lilypad liPower which i have (LilyPad LiPower - DEV-08786 - SparkFun Electronics) does have "terminals for charging an attached LiPo battery with one LiPo chargers."
roll over "C", bottom left: LilyPad LiPower | low profile rechargeable battery board (sp… | Flickr .
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!

5

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!