From: [IDC]Dragon <idc-dragon_at_gmx.de>
Date: Wed, 4 Aug 2004 21:10:53 +0200 (MEST)

> THat only matters at end of charge. When the battery is discharged, it
> will
> accept pretty much any current thrown at it. The only limitation being
> that
> the current should remain below the mfr's max charge rate. That is
> usually
> C/2 or C/3.
>
> Since the objective here isn't to fully charge the battery but merely to
> put
> back enough charge to let the machine boot, there is no need for any sort
> of
> battery management.

This is pretty much correct. LiIons are tricky to fully charge to the
capacity. A good part of the capacity gets filled when the cell is already
very close to the cutoff voltage, which must never be exceeded. The
regulators have to be very precise to fully exploit this, and have to match
the cell.
This is why I said 4V sharp, then you're on the safe side. The internal
charger goes up to 4.2V.

At the start of the charging, the cell may rather be 3V when you apply some
current. if you let is rise to maybe 3.5V or so it should be enough to start
the box and continue the charging in there. Don't let is raise above 4V!

Please note that the battery pack consists of two cells side by side. They
are connected in parallel only if in the device, have no connection on their
own. So you have to charge 2 cells externally, each for a while, or both at
the same time, whatever is more convenient to hook up.

Jörg

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Received on 2004-08-04