>>it doesn't take a math genius to figure that with 4-"AA" batteries
>>at 1.5volts per battery. To drop from 6volts to 5volts means that
>>each battery looses .25volts (that's a quarter of a volt) That
>>means that the battery still has 80% of it's capacity!
>If I ever go into space I want Ed and PCBman in the capsule!
With physics like that Ed is not allowed in my capsule. ;-) The
relationship between cell capacity and voltage is and needs to be
more complex than a simple linear one. It probably looks roughly more
like a damped exponential decay curve from a constant voltage like
this:
---------------------------
-------
-----
---
--
-
-
-
--
---
-----
---------
Most devices (torches excepted) will be designed to operate only at
or near the top of the curve. The drop in power may be fast when it
starts in earnest, and 'capacity' i.e. total/remaining charge stored,
measured in Coulombs or Amp Seconds (mAh even), will be related to
the area under the graph rather than the voltage line plot itself. At
80% capacity the cell should still be producing 1.5V. At 1 V there
would be little useful capacity left.
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