Battery question

Last year (2004) I had bought some Turbo Flares out at Sams Club on clearance due to this tread. I had put Energizer Lithiums in it as I was hoping they would withstand the heat and cold better than alkalines. Last night when I finished jumping someones car I saw the turbo flares in my trunk kit and decided to try them. They didn't work sadly.

So this morning after I woke up I took the batteries out and measured them on my multimeter. A few measured a measly .43 volts, two measured 1.25 and 1.14, while two batteries measured -.73v and -.05v.

What causes batteries to reverse polarity like that? I'm pretty certain that the button didn't get pushed on them while in my trunk kit. Not much room for them to move at all, and they would have to hit the corner of something to even get the button pushed as it resides between the feet of the unit.

That is a mystery. I haven't been measuring dead battery voltages for very long but of the ones I have measured the ones depleted on their own don't seem to ever reverse like that. I could assume if a few cells did die AND you turn it on that could lead directly to reversal as the dead batteries would be forced to pass the current of the good ones through them thus reversing them.

Could be you got a bad batch of batteries, some good and some bad.

Yes I find it a mystery. I have a 6AA Energizer double barrel flashlight with Energizer Lithiums in it and it sits inside my car for easy reach. And that was working fine last night.

Current leakage due to bad design/corroded contacts?

Since there is a GB on the TurboFlares going on maybe one us could test to see if they leak current. I would bet lunch that they do not. If they leak current, it seems we would have heard about it already.

However, the switch is very sensitive on these lights. It is plausible that the unit was turned on for say a week or two (it is not necessary to fully depress the button for it to turn on), but then later it shifted again in storage.

Of course bad batteries are always a possibility.

Geo

The only way I have seen batteries reverse voltage is when they are stacked in series and power is being drawn. If you let them sit forever they won't reverse on you, just go flat. So somehow there was a draw on them. My guess is the light's button somehow got depressed just enough to come on without "clicking" on and ran them dead.

I would have to side with the idea somehow it got turned on by partial depression of the switch in the box long enough to drain them, but it is easy to check for current leakage with a DMM in all but the switch itself.

If you find even a tiny current drain it can add up over time. I had a touchlight with a timer off circuit that I modded with 4 LEDs and it kept eating my 1500mah nimh batteries every few weeks. I thought the batteries were bad but after charging them a few times I suspected there was a current leak and testing it showed the timer circuit had a standby idle current of 4ma or so which added up to 1000mah in a week thus killing the batteries between using it and sitting.

Put alkalines in it and tape a cap off a bottle over the button and stick it back in the trunk if you don't find anything wrong with it and if 6 months from now the batteries are good it was coming on via external button manipulation.