Rich Grise said:
Yes - never discharge your pack to the point that any cell reaches
zero volts. By the time the reverse voltage across the cell reaches
a diode drop, the cell has already been destroyed.
In other words, don't do it.
Sorry,
Rich
Sorry, Rich, but I don't think your answer is very useful...
Unless I'm misunderstanding him horribly, he's looking for info on what
to use as what I've always heard called "steering diodes", so that no
matter which way a battery/battery pack gets hooked to the circuit, the
polarity is correct, not info on keeping a dead cell from reversing a
pack.
Royal:
What I've always done (in non-weight-critical applications) is "over
design" the power supply (Add an extra cell, ferinstance) appropriately
to compensate for the diode drop that will be involved, and then plug
the power (Either AC or DC...) into a bridge rectifier's inputs. Put DC
on the inputs of a bridge, and it's going to put out DC of the right
polarity on the output pins regardless of which way the supply voltage
is hooked up. Free bonus: If your circuit doesn't have a problem
handling AC ripple, you're also set to just hook up the correct voltage
AC (from an ultra-cheap wall-wart, for instance) to the same pins you'd
hook the battery to. If it does have a problem with ripple, a couple of
caps and coils "downstream" from the power input can easily clean things
up to tolerable when used with AC, yet sit there quietly doing nothing
if the device is being fed DC.
