> Anyone know of a method of detecting if a battery that is inserted into a
> charger is alkaline or nicad/niMH?

Drive the battery with AC.
Mount a capacitive plate facing the side of the battery.
If the received signal from the plate is in phase with the positive pole,
it's alkaline.

This works because the outer case of alkaline batteries is positive,
nicad/nimh have negative case.

Whether you can get it to work in practice is an excercise left to the
experimenter.

What do you want to bet someone has attempted to patent this idea already?
If not, the piclist will count as prior art, please give me credit :)

-Bob Blick

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