BatteryStation 123A goes boom in a G2 with Kroma TailCap"

[kumar762]

The other day I had a surefire G2 explode in my pocket.Here was the setup:
Surefire G2(duh!)
Pyrex lens
battery station 123A's
KROMA tailcap
P60 lamp assembly
When the one of the lithium batteries exploded the light was very hot and the tailcaps rubber boot was about the size of a golf ball,the lens and nylon ring were blown right off the bezel.I have yet to know the casue of this but i suspect the dual stage tailcap and the battery stations could be something to worry about.It gave off quite a smell when I pulled it out the pocket

,it was also very hot so I ripped off my kroma tailcap and chucked the rest off the light out the window which I later recovered.There was a black residue everywhere.If anyone has any insight on this please let me no.

 

[Size15's]

Re: G2 goes boom!

Why were you using the Kroma's two-stage TailCap on a G2?

Was it locked out at the time?

Please can you post some photos.

This is not the first time CR123A batteries have 'exploded' in a flashlight. The CR123A batteries explode all sorts of nasty chemicals. Handle the flashlight with extreme care wearing gloves and outside in moving air.

Al

 

[kumar762]

Re: G2 goes boom!

no it was not locked out .I'll post some pictures of it when i get home later on tonight.I forgot to add that the lamp assembly is now dead.I was using the tailcap on the KROMA because it worked awesomely with a high and low beam.

 

[dchao]

Re: G2 goes boom!

You should change the title to:

Battery Station 123A's go Boom

:thumbsdow

 

[Size15's]

Re: BatteryStation 123A goes boom in a G2 with Kroma TailCap

You should change the title to:
Battery Station 123A's go Boom
:thumbsdow

In the attempt to be accurate perhaps the title should be "BatteryStation 123A goes boom in a G2 with Kroma TailCap".

Certainly Battery Station CR123A's have been reported to 'explode' before but in this case I make the assumption that the flashlight was allowed to be switched on unattended in a confined space which is not good for any brand of CR123A. I don't know whether Battery Station batteries are any more likely to fall under such circumstances. I don't know whether the two-stage TailCap made matters worse.

Bottomline: The flashlight should have been disabled for transporation/carry in a confined space in which it could easily be activated.

 

[Amonra]

Re: G2 goes boom!

is there a possibility that the kroma tailcap ( or something else for that matter ) shorted the batts ? that could explain why it got so hot.

 

[js]

Re: G2 goes boom!

kumar,

DO NOT BREATH ANY OF THE FUMES. DO NOT TOUCH ANY OF THE RESIDUE. BE CAREFUL. THIS STUFF IS TOXIC!

As for why it happened, I have a pretty good guess, depending on how the Kroma tailcap works:

If it works like the A2/L1/L2 LOTC, it has a small value resistance when it is turned back just enough to not be fully on. Thus even though no light was coming from your filament, it is likely that something like a 10 ohm resistor was in series with the filament and battery, thus drawing 300 mA of current through the circuit. Not enough to light the filament, but enough to drain down the batteries. ALL THE WAY. And if one battery was in a different state of charge than the other, you get one battery actually CHARGING the other, when the low one gets cell reversal. Re-charging primary 123's is bad, bad, bad. So it goes BOOM!

I'm pretty sure that the BS 123's have been experiencing some problems with self-discharge rates all over the map. So in a batch of 12, 3 may go down to 20 or 10 percent, and the others stay up at 90 or 100.

Result? Radical cell mis-match.

In any case, take care of yourself and those near you. Don't breath fumes. Wear gloves. And especially don't let pets get anything on them.

Be careful!

I'm sorry this happened to you, and I'm glad you weren't injured.

 

[Size15's]

Re: G2 goes boom!

Jim,
Your reasoning seems reasonable.
One thing though - I've carried the A2, L2, L1 and "Kroma" for ages and ages putting I guess in the region of over a hundred sets of batteries through them and never experienced any unexplained or unexpected short runtimes. Mostly the TailCap is left so that only the low beam can be activated momentary on/off when I carry them clipped inside my pocket.

Could it be that the low beams of the L1/L2/A2/K2 are so easy to drive that the two-stage TailCaps when the resistor is in ciruit result in light output. Compare this to the unregulated P60 which is much harder to drive and I can understand that the two-stage switch (which is only intended for the Kromas) can cause the batteries to drain without the P60 illuminating if not locked out.

Al

 

[Art Vandelay]

Re: G2 goes boom!

You might want to see a Doctor just in case. Are you feeling short of breath?

How tight was the spring when you put the Kroma tailcap on the G2?

 

[js]

Re: G2 goes boom!

Al,

Yes. Exactly what I was thinking.

Using a Kroma or A2 tailcap in a Kroma or an A2, WILL ACTUALLY RESULT IN LIGHT OUTPUT when the tailcap is in the "low-beam" position. So when you turn it off, you REALLY TURN IT OFF--all the way to the point where the 10 ohm resistor is not in circuit anymore (but not necessarily to a lockout position).

However, using that same tailcap in a light driving only a P60 or P61 (or similar), and the low current that the tailcap passes in "low' positon, is seen as being "off" becuase there is no light.

This, will, however, drain the batteries nonetheless.

That said, I know nothing about the Kroma tailcap. Only saying that IF it were like the A2 LOTC, then I had an idea. Most times when one of your cells reverses, the light output goes very dim, giving you a headsup--TURN OFF--but not i the case considered here, as there isn't even light output with two fully charged 123's. (In this theory, anyway)

That all by itself wouldn't be enough, though. If the cells are matched, and you draw them down, they just go dead. You need one to be nearly dead, and one to be full. That's when you get the cell reversal, and then one cell charging the other.

Those are my thoughts, anyway. FWIW. Just a theory as to what MAY have happened.

Does anyone know for sure exactly how the kroma tail cap DOES work, BTW? Because, it would seem to be a bad idea to use it in anything but the kroma I would think.

 

[Size15's]

Re: G2 goes boom!

My understanding is that the Kroma TailCap works exactly like the A2/L1/L2 TailCap.

 

[kumar762]

Re: G2 goes boom!

yeah I didn't want anything to do with the fumes and such so I chucked it out the window,then later went back and retrieved the remains.the cells were not mis matched either I had pulled them out the package the day before:thumbsdow .I have used the KROMA tailcap on the P60 before and It worked great,but the first time I did I used energizer 123A's.I'll be changing the title.

 

[BBL]

The chanze to find two cells with the same charging level in a batch of 50 battery station cells is about 1:10 ... at least was that the case with my '05 batch of 50 cells.

It seems plausible to me too, that the tailcap was in low mode and drained the cells to zero, with nasty results.

 

[Size15's]

Re: G2 goes boom!

the cells were not mis matched either I had pulled them out the package the day before:thumbsdow

I think the point is that its not possible to tell whether they are mismatched without carefully testing them first.

 

[kumar762]

I've already inspected the tailcap for damage and it highly resembles the tailcap of my L2 no differences that I can notice.I can sure say it scared the crap outta my girlfriend when this thing went off!!:lolsign: maybe it's time for a tester from lighthound?

 

[kumar762]

HMMM?? maybe this is why PK chose to regulate the A2?

 

[carrot]

Please post pics so that we may examine the extent of the explosion?

 

[js]

kumar,

This could happen to the A2 as well. The regulation wouldn't stop this from happening. What would stop it from happening would be the fact that you would turn off the light, and would not leave it ON unwittingly.

It probably boils down to these things:

1. Using the kroma tailcap meant you were draining down the cells and didn't know it.
2. The cells were mismatched and you didn't know it. This isn't your fault! There have been a rash of such issues lately. First with the AmondoTech Titanium 123's, and next with the BatteryStation 123's. You buy a box of them and expect them all to be fully charged, right? I mean HELLO! They are all new, so they should all be 100 percent full, right? Unfortunately, no. I had 30 Titanium 123's go south on me, some of them to nothing, some to half charge or so, and some didn't go south at all and were still close to 100 percent.

This is a disastrous situation, ESPECIALLY, if you have no way of telling when (and if) one of the cells undergoes cell reversal.

When cell reversal happens, the positive and negative contacts switch polarities, just as if you had the cell inserted into the light backwards. Now, normally, if that happens, your light output will just SUCK because the voltage of the one cell counteracts the voltage of the other cell. (The reversed cell's voltage is lower than the good cell, so you still have SOME total voltage)

But, in your case, I suspect that you were drawing a small current for a while before, when you thought your light was "OFF". It was, in the sense that it was making no light, but it was NOT, in the sense that current was still flowing and the weak cell was drawn down to zero, then reversed, then charged, then exploded.

That's the theory, anyway.

What was happening before you picked up the light? When was it that you installed new batteries? And did you move the tail cap position from install until activation? What exactly happened? The more details you provide the better.

 

[greenLED]

post pics, kumar, so we can assess the damage better

 

[kumar762]

I can't post them now i won't be home for another hour or so,therefore I don't have access to the light,but yes I believe you are right If the tailcap does discharge with my knowing then that's what happened I keep my lights on a standby type deal when I'm out and about.So it was not locked out.I think I'll be sticking to the SF123A's from now on just to be safe . . . .and no more kroma tailcaps on incans . . .which is unfortunate because It worked so awesome