In reading something here, my curiosity caused me to get out my Tek DMM and check out the Voltage of some AAA NiMH I had.
They were charged, but it had been several weeks. So I did find one of them was about one Volt, and before I put it away, I pushed the Ohms button, and shorted my probes to see what it would read. Got about 1.5 Ohms, but noticed it was unstable, the digital display would hardly stay on one reading - between 1.1 and 2.0 or so. My probes are nice shiny ones, but no matter how I held them, the reading would shift.
Took a notion to try some contact cleaner. Sprayed some Deoxit D-5 and in the recessed banana connector end, wiped everything with a saturated corner of a paper towel and then plugged 'er up again.
Now I get a rock solid 0.6 Ohm reading, and a steady indication, with very little dependency of the probes position and pressure. Wow.
Re-tried my Voltage measures and found they also were more stable.
And you know, with 1.3V supply, a few tenths of an Ohm might just make a difference in the way a flashlight works. Used that paper towel to rub the electrodes of every battery I had out.
I have noticed some stability changes after applying contact cleaner on lights in the past, but never tried to measure anything.
They were charged, but it had been several weeks. So I did find one of them was about one Volt, and before I put it away, I pushed the Ohms button, and shorted my probes to see what it would read. Got about 1.5 Ohms, but noticed it was unstable, the digital display would hardly stay on one reading - between 1.1 and 2.0 or so. My probes are nice shiny ones, but no matter how I held them, the reading would shift.
Took a notion to try some contact cleaner. Sprayed some Deoxit D-5 and in the recessed banana connector end, wiped everything with a saturated corner of a paper towel and then plugged 'er up again.
Now I get a rock solid 0.6 Ohm reading, and a steady indication, with very little dependency of the probes position and pressure. Wow.
Re-tried my Voltage measures and found they also were more stable.
And you know, with 1.3V supply, a few tenths of an Ohm might just make a difference in the way a flashlight works. Used that paper towel to rub the electrodes of every battery I had out.
I have noticed some stability changes after applying contact cleaner on lights in the past, but never tried to measure anything.
