On Dec 7, 2004, at 7:42 PM, Chetan Bhargava wrote:

> I was wrong about number of cells in the batteries. I found out that
> NP-F330 has 2 cells and the voltage rating on the battery is marked
> 7.2V so that means 3.6V per cell. Assuming that the infolithium cell
> is 3.6v, NP-FC11 will have only one cell.
>
Li-ion cells do not have as flat a discharge curve as NiMH or NiCd, and
"consumer" battery packs are rated at 3.6 to 3.7V per cell.  I guess 
that's
supposed to me an average of the 4.2V "freshly charged" state and the 3V
"fully discharged" state.  They still get charged to 4.1 or 4.2V 
depending
on exact cell chemistry.

Rumor has it that you can get extended numbers of charge cycles by 
charging
your batteries to a somewhat lower-than-optimal voltage (you sacrifice
capacity, of course.)  More dangerous rumors (as in batteries 
"exploding and
catching fire.  Dangerous for real, not just dangerous to the battery 
spec) are
that you can get a bit of extra capacity out of a Li-ion battery by 
charging
it to above the 4.2V level (at the cost of decreasing cell life, even 
if you
avoid fire and explosions.)

BillW
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