Testing battery condition

[Mike Barnes]

Is there an easy way to tell how much life there is in a part-used alkaline "C" cell? At this time of year I remove quite a few from our irrigation timers, which have done their job for the season. It seems a waste to throw these batteries away, but I'm reluctant to use them again next season because the cost of failure would be too high. We don't have any other battery-powered devices that use this size.

[The Natural Philosopher]

The best thing is to put them on a decent load - from memory what happens to old alklines is that they still have volts left...but those volts do not last for very long under load.

Try a sort of amp for a minute test, and f they show a volt therefater, they may be useful

OTOH that is te sort of thing I would not take a risk on. Scrap them all and new in as a matter of course.

I don't do particle analysis on the oil that cpmes out of my engine and pour it back in either :D

[manatbandq]

Make a few of these

give the batteries away to someone who can use them, don't just dump them.

MBQ

[bland]

Looking at

end of life volts for alkaline rated capacity is 0.8v but I guess the electronics will have stopped working by then. Suggestions (i) find the equipment current consumption from the manual and calculate what the life should be. If they are run to half life, over two season that should be about 1.15 volts so 1/4 life at the end of the first season should be around 1.325 volts.

(ii) if they measure above 1.325 volts at the end of the first season, plus they give > 5A on a short circuit test on an AVO, they should do another season.

(iii) I accept no responsibilty for lack of irrigation

bland