Ultrafire WF-500 Xenon Flashlight "explosion"

[jalbam]

Hello!

Well, is not an explosion... I think (because I didn't heard a "boom", only a "buzzing")

Today arrived this flashlight (http://www.dealextreme.com/details.dx/sku.1317) from DealExtreme and I tried it with two unprotected 18650 wich I bought there before (TrustFire 18650 3.7V 2500mAh Rechargeable which you can found here http://www.dealextreme.com/details.dx/sku.19770).

I have to say that these batteries were working a lot of times very well with other flashlights (single 18650) without any problem. They were from the same batch (they two came together).

I charged both 18650's days (may be two or three weeks) ago and I haven't used them since today. So, they were (maybe almost) fully charged.

I put them into the WF-500 Xenon flashlights and it were working well. I disasselbed the flashlight to clean it with a tissue (I didn't touch the bulb). Then I assembled it again and it didn't turn on but I could heard a little sound like a buzzing or someting like that. The sound stoped when I tried to turn off (despite the flashlight didn't light at all). Then I tried to turn on again and it didn't work either but I started to smell a strange odour.

When I disassembled it again I could see one of the batteries a little bit melted (only on the positive pole I think) and still smoking a little bit. I discard the melted battery (it is in the bin of the batteries right now) but the other one looks good and I decided to tried with another flashlight and it seems to work very well.

Now the bulb spring of this flashlight is mixed with a sustance which is now solid (I think is plastic from the battery label). It smells weird.

The WF-500 Xenon still works but with other cells. Now I am using it with this cells (they are protected but work well): http://www.dealextreme.com/details.dx/sku.4757. EDIT: Sorry, the batteries with sku.4757 doesn't work, It was my fault. These are the batteries which work: http://www.dealextreme.com/details.dx/sku.19624

Then I am wondering either if the problem is from the flashlight or is from the cells? Could it be from both?

It is safe if I continue using the cell without visual damage with single cell flashlights? I am afraid of explosions and such.

My room continues smelling a little bit strange. The most important question for me is: is it bad for my health? I am feeling well, but I am afraid. May be the smoke is very bad and I should go to the doctor, but I am not sure.

Here are three pics (sorry about the bad quality):

...Yes I know that the two last pictures are very bad quality, I'm sorry for that. But in the first one you can see the battery melted (it only was melted on the positive pole I think).

Thank you very much in advance and sorry about my Enlglish

Cheers,
Joan.

 

[Phaserburn]

It sounds like one of the batts shorted. The light itself being xenon has no circuitry to fry. Using the cells you did might be the culprit. I don't run anything other than AW 2600 cells in my WF-500 because of the 3A current draw. Alot of li-ions say they can handle the load, but their circuitry really can't; I've tried many. If the light works with other cells, the batts are definitely the culprit.

 

[jalbam]

Thank you very much for your fast answer

Do you think that the other battery which is not visual damaged is safe to use? I mean as safe as was before this issue (I know that UltraFire batteries are not so safe and ever less if they are unprotected).

Why do you think they sorted? Why is only a cell visual damaged and not both?

Yes, the flashlight still works. Should I be afraid of this flashlight or only of bad-quality cells? Or may be should I be afraid of both?

In the future I'm going to buy good quality AW cells

Thank you very much,
Joan.

 

[SilverFox]

Hello Joan,

Welcome to CPF.

It could be that the first cell shorted out between the + button and the side of the cell. That would produce the melting you are seeing. In this case, the second cell would be OK to continue to use.

I don't have that light, so I can't comment on how it happened, but sometimes cells are a little different diameter, or spring contacts get bent a little, and a short develops. It looks like the spring could have gotten push to the side, but the picture is a little blurry...

It sounds like you stopped things before they got out of hand, so it is most likely that only a little venting occurred. The best thing to do is to air out your room to get rid of the odor. Pay attention to yourself and if you notice any related adverse effects, discuss them with your doctor.

Take care and play safe.

Tom

 

[qwertyydude]

Use this as a lesson not to use unprotected cells. Those cells were unprotected and it looked like it shorted at the burned area and button.

 

[rizky_p]

Should have been using protected batteries especially on lower quality flashlight. I know unprotected is cheaper, I've been using some OEM Sanyo 18650 2400 for sometime, they cost 7USD each or 5usd/100pcs in local shop and performs the best.

 

[Phaserburn]

Also, bear in mind that a 3A incan will draw more than 3A on startup, contributing to the sudden strain on the cell. This is why some mod lights with "soft starters". If you use good quality cells, you'll have no issues.

I use mine fairly regularly for 20+ minute continuous runs with no worries.

 

[jalbam]

I used protected batteries because I read that WF-500 Xenon needs to use unprotected batteries because only a few protected batteries won't work.

One of the protected batteries which works with this flashlight are protected AW's but I don't have any yet. I will buy these in a future.

I edited the first post because I made a mistake. The batteries which I'm using now with the WF-500 are these: http://www.dealextreme.com/details.dx/sku.19624

They are protected but work well.

By the way, I have a Philips Focusline G4 (here it is http://www.dealextreme.com/details.dx/sku.12126) but doesn't work when I put it on the WF-500. I don't know if it's a problem of the Philips bulb or it's a problem from batteries. The batteries work well with the default bulb of the WF-500, so I think the bulb is wrong. How can I be sure? I can't notice any wrong on the bulb (filament seems to be good).

 

[LumenHound]

The high inrush current of the Focusline bulb at start up may be just beyond what the protection circuitry of those batteries will allow.

If you have a multimeter you could measure the resistance of the filament to determine if the filament is broken. If it measures in at less than 1 ohm it's a good bulb.

 

[jalbam]

Thanks for the reply. But I don't have any idea about what is a multimeter and I don't have one hehehe

But now I am happy because I haven been reading forums and I found an idea what I did:

I used an 4,5v cell to connect the bulb to it. The inner spring to positive pole, the outer to the negative one. The Philips bulb lighted up, so I think is not broken and the problem is in the cells. But the new problem is that is really dim. It could be only for the low voltage? I know that 4,5v is not too much, but the bulb was as dimmer as a generic LED keychain or even more.

Thanks,
Joan.