Pop Goes a Flashlight

Recently I received a fine gift from a fellow CPFer (bondr006). It was a surprisingly decent 99 cent light he found somewhere and bought a bunch. So, I was using it to drain and old alkaline. Had it tail standing when it suddenly just fell over. Right after I picked it up the switch boot went "bang". This came as quite a surprise. Didn't know what had happened at first.

No problem with the light now, except a hole in the boot.

Geoff

Alkaline vented? I thought they just leaked?

We've seen this occur in 2-cell lights on some occasion, although usually the rubber boot just stretches instead of pops.

You should have posted this in the Budget Forum, where they would explain to you why this is a perfectly reasonable thing to have happen, and where you can order replacement parts that will take several months to arrive..

There have been reports of alkaline venting... so yours does not surprise me.

I've had it happen to me twice in the past few weeks on almost two consecutive days. The first time it was a pair of alkaline cells in a Mini-MagLite with the Nite-Ize 3-LED drop-in. It was drained a lot too far and I heard a "pop". I dumped the batteries on the ground and one of them had popped like a pimple, spewing a bit of battery acid on the inside of the flashlight body. Two days later I was using a Pelican Versabrite that I had modified to LED and I heard it pop as well. This time I was lucky in that there was no battery acid to clean up. I've since switched over to NiMH cells so I won't be experiencing that again.

I think this is why some of the waterproof dive lights have a pellet in them to absorb excess gasses and prevent the "pop" but don't quote me on that.

Flying Turtle said:

... So, I was using it to drain and old alkaline. Had it tail standing when it suddenly just fell over. Right after I picked it up the switch boot went "bang".

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Hi Geoff,

That's why I avoid fully draining alkaline batteries and replace them when the voltage falls below 1.3 volts or so.

I think fully draining batteries increases the chances that they will vent, leak, and damage the flashlight.

I use a cheap xnova I paid $2 for and a 4AA battery holder hooked to a luxeon circuit out of an old 3AAA headlamp with a potentiometer hooked between it as a computer keyboard light to drain batteries. If it leaks it may ruin a $2 battery holder and I have drained dozens of batteries to unusable levels with it. I think the pop happens less often when drained at rather low current levels.
I agree the chance of batteries leaking increases dramatically when the voltage drops below 1v especially when used in series as one battery can be driven to 0v or even reversed which I think increases chances even more.

Lynx_Arc said:

I think this is why some of the waterproof dive lights have a pellet in them to absorb excess gasses and prevent the "pop" but don't quote me on that.

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Yup. Pelican's sealed lights (and others I'm sure) have pellets in them to absorb hydrogen gas.

Right after this occurrence the battery looked normal. Looked at it yesterday and it had leaked badly (on the workbench). I know this is risky, but I've been doing it for years. I do reserve this practice for "special" lights and rarely use anything but NiMH's or lithiums in good lights.

Geoff

Flying Turtle said:

Recently I received a fine gift from a fellow CPFer (bondr006). It was a surprisingly decent 99 cent light he found somewhere and bought a bunch. So, I was using it to drain and old alkaline. Had it tail standing when it suddenly just fell over. Right after I picked it up the switch boot went "bang". This came as quite a surprise. Didn't know what had happened at first.

No problem with the light now, except a hole in the boot.

Geoff

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What is the purpose of draining old batteries, when mine drop off and I can no longer use my brightest level I replace my batteries and then put the old ones in the recycle trash can. Is it better to drain them totally first or what is the reason.

I have no good purpose draining the batteries. I'm just cheap and hate to throw something away that still has some use. Usually I'll set up a light to function as a night light while the battery is drained.

Geoff

Flying Turtle said:

I have no good purpose draining the batteries. I'm just cheap and hate to throw something away that still has some use. Usually I'll set up a light to function as a night light while the battery is drained.

Geoff

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That's cool, I know there is a lot of useful light left in my batteries but I don't want to ruin my good light but that is a good idea maybe I will pick up a cheap light and start doing that. Thanks

turtle , how close to sherron harris, i have a theroy. just kiddin. good luck homeboy..................marty

I guess I'm close enough to the plant. Just a couple miles closer and I'd get a free radio. Hopefully Homer isn't working out there. Or maybe he is. My nose does tend to glow in the dark a bit.

Geoff

So from a newbie perspective...Is this a problem with the $.99 light or is it a battery failure? Both???

My Nitecore D10 went pop after draining an alkaline and unscrewing the head.

Soon after I showed somebody just how tough an EO1 was by throwing it against a wall, I noticed that it was a lot tougher to twist the head on the light. When opened, it popped. Turns out the alkaline in it was venting.