LiPo charging is a well developed technology.
Check out:
http://www.fmadirect.com/support_docs/item_1266.pdf
This handles up to a 10S battery setup Quickly, safely, and babies the=20
batteries. Over kill, I think, for your App but a good place to learn a bit=
!

On 5/14/2012 6:17 AM, cdb wrote:
>   I'm just kicking this around and would be interested in other thoughts.
>
> In the R-Pi E-14 forum someone wanted to know if there is such a thing as=
 a
> series connected lithium battery charger.
>
> I suggested a module made up of a lithium charger IC,  a switching
> mechanism that could isolate those batteries in the chain (envisaging no
> more than 3) once they've charged and some form of electronic load
> (probably a FET). It has been proposed that each  battery could have its
> own switch controller and thinking about this a small Pic or Atmel chip
> could be used to provide the intelligent switching per battery with the
> charger/battery gauge chip providing the correct charging algorithm, the
> controller chip would either switch it out of the pack chain or
> alternatively switch in the active load to maintain that particular batte=
ry
> charge state.
>
> Does this seem workable in theory?
>
> Colin
> --
> cdb,   14/05/2012
>
> --
>
>
>
>
> colin@btech-online.co.uk
>

--=20
John Ferrell W8CCW
=93During times of universal deceit,
   Telling the TRUTH becomes a revolutionary act=94
      George Orwell


--=20
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