"rebel" wrote in message
...
On Tue, 17 Mar 2009 09:58:17 -0500, "ps56k"

wrote:

it's interesting how battery specs are tweaked
to show more power.... even Dell -

ie -
Dell CG039 battery lists as 9cell @ 85Wh
the "key" is what is used as a base voltage - 10.8 vs 11.1-
which is interesting as most all rechargeables list as 1.2v
9 x 1.20v = 10.80v
9 x 1.24v = 11.07v

11.1v x 4800mah = 53Wh (NF343)
11.1v x 7600mah = 85Wh (CG039)

Other battery vendors -
10.8v x 6600mah = 71Wh
10.8v x 7200mah = 77Wh

It isn't 9 cells @ 1.2V. It is 3*3 at 3.6V, or in the other case 3.7V.
The
quoted nominal cell voltage of Li-Ion cells depends on who wants to
impress whom
as much as any clinical arguments.

Using a charge termination voltage of 4v20 (the notation I prefer) and an
end-of-discharge voltage of 3v0, the average is 3v6. Under constant
current
discharge the voltage curve is reasonably linear so using the average is a
reasonable approach. However under constant power discharge the curve
becomes
steeper as the voltage drops, so 3v7 is more relevant in some arguments.

huh - math is the same
9 x 1.2v = 10.8v
3 x 1.2v = 3.6v x 3 = 10.8v

the real question(able) issue,
is using something other than 1.2v per cell.