> Yes about that. At 1V or lower you increase risk of suddenly reverse
> charging one cell (sudden drop to under 3V).

Yes. That's something I didn't mention.
As long as cells are not run close to discharge this is not an issue
but if the "battery" is allowed to run flat (fully discharged) then,
as Michael notes, one cell will run out of capacity first and be
driven into reverse polarity by the discharge current from the other
3. With NiCds this can result in the cell having a "whisker" hard
electro-plated across the cell, leaving it permanently short circuit.
While this whisker can be "burnt down" the cell will usually be
permanently damaged. NimH tend not to grow whiskers but discharging
any cell fully will shorten lifetime and is "not recommended".

> I seem to have duplicated a lot of what you said... I should check all
> my email when I get up before opening my mouth for other than coffee.

That's certainly true for some people here :-) - but you managed to
cover a number of things that I didn't. (And good points often bear
reinforcing :-) ).


                  Russell
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