Hotwire Disaster Kills 12 Eneloops --PICS ADDED--VIDEO TOO--

sed6

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Hotwire Disaster Kills 12 Eneloops

updated 11:42 p.m. EST, Sat January 26, 2008

Oklahoma City, OK (CPF) – In an attempt to create his first hotwire mod, Sed6 killed 12 brand new Eneloop 1.2v rechargeable batteries late last night, officials say.

Sed6 is a budding flashaholic, someone who collects, modifies or generally just loves flashlights and most anything flashlight related. In the recent months since his addiction set in he has limited himself to drop-ins and other easy mods. It was only after obtaining parts for a more advanced mod that the stage was set for this disaster.

"He's fairly competent, but he took on a project above his understanding." said a fellow CPFer. Sed6 assembled the needed parts for this hotwire mod from various sources; a metal reflector, bi-pin adapter, 3AA-1D adapters from Kaidomain, a 4D Mag host from his local Wal-Mart, and the Eneloops from Circuit City.

The bulb used, part #3482, was rated at 6v and 20W and was also obtained from Kai as part of a series of bulbs tested by Sed6. Two other bulbs, #3486 and #3488 provided satisfactory results but "were no brighter then my 6D ROP," said Sed6. The #3482 bulb was driven by 12 Eneloops in series putting out 16.35v at 4.38amps and all cells were contained in Kai cell holders.

The test started well with a blinding, brilliant white light, onlookers reported. After 2 minutes the head was very hot and the body was quite warm. After 3 ½ minutes the head was too hot to touch and the body was very hot as well. At about 5 minutes witnesses reported hearing a "popping and sizzle" sound coming from within the body of the light. "I don't know why but Sed6 didn't turn the light off right way," one witness said "instead he grabbed his camera and looked like he was going to take pictures."

About 30 seconds later the light was turned off and the batteries in their holders, dumped out. The damage however was already done. Initial inspection showed all the cells had melted wrapping on the outside, some were even bubbling. As well 4-5 of the batteries were actively venting, releasing noxious gases into the room, officials said. Also of note, all 4 battery holders were firmly melted together. Also melted was the bottom of the switch mechanism and the top of the switch where the bulb is held. "It just got too hot," one expert said, "a few more seconds and the explosion would have leveled his house."

Sed6 is now seeking an understanding of what went wrong. "Clearly volts, amps, current and resistance all play a role here, but I'm not sure exactly how," said Sed6. "I know others have done similar mods without the disastrous results." "I guess I just need a little advice from those with more experience."

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Re: Hotwire Disaster Kills 12 Eneloops

Hello Scott,

My first guess is that something shorted out.

The Eneloop cells warm up, but can still handle, 10 amps without too much problem. To get to the temperatures you experienced, you need to be drawing much more than that. To drain the cells in 5 minutes, you need to be drawing in excess of 20 amps.

Tom
 
Re: Hotwire Disaster Kills 12 Eneloops

That's AWESOME!

I wish you took video! I'll bet you do a little more reading on Hotwire projects such as the simple M*g85, M*g11, or ROP. Sometimes it really pays off to use products built to withstand that kind of heat, ex. look at the FiveMega battery holders. High resistance causes a LOT of heat, hence the melting battery holders.

It's too bad you killed those Eneloops, the other items don't seem like much of a loss.

You were driving the heck out of that bulb!!
 
Re: Hotwire Disaster Kills 12 Eneloops

Lol, excellent report - you are sure to get a Pulitzer Prize for that.

However the CPFBI is already on the case, conducting an in-depth investigation about the appalling mass-slaughter of those 12 poor innocent little Eneloops, lol.
 
Re: Hotwire Disaster Kills 12 Eneloops

[The bulb used, part #3482, was rated at 6v and 20W and was also obtained from Kai as part of a series of bulbs tested by Sed6. Two other bulbs, #3486 and #3488 provided satisfactory results but "were no brighter then my 6D ROP," said Sed6. The #3082 bulb was driven by 12 Eneloops in series putting out 16.35v at 4.38amps and all cells were contained in Kai cell holders.

Is this a typo? Were you actually driving a 3482 at 16.35V or a 3082? That might just turn out to be a problem. I'm not sure a 6V bulb wants to see 16V, ever.

How did you arrive at 16V anyway - by measurement? I thought the holders put the cells in parallel so you ended up with 6V -four sets in series of three cells in parallel.
 
Re: Hotwire Disaster Kills 12 Eneloops

Very entertaining post. Sounds like a short to me.

MSax
 
Re: Hotwire Disaster Kills 12 Eneloops

The CPFBI - I Love it!



...However the CPFBI is already on the case, conducting an in-depth investigation about the appalling mass-slaughter of those 12 poor innocent little Eneloops, lol.
 
Re: Hotwire Disaster Kills 12 Eneloops

Is this a typo? Were you actually driving a 3482 at 16.35V or a 3082? That might just turn out to be a problem. I'm not sure a 6V bulb wants to see 16V, ever.

How did you arrive at 16V anyway - by measurement? I thought the holders put the cells in parallel so you ended up with 6V -four sets in series of three cells in parallel.

Definately the 3482. I was pleased I could go so high on a 6v bulb! The voltage was easy to arrive at, I lined up all 4 battery carriers end to end and measured the volts. So it wasn't voltage under load, which was prolly closer to...12v?

I only let it run so long because I thought the heat was just from the bulb, not the batteries. In hindsight about 3 minutes into it I noticed the bottom of the light was warmer than the middle of the light, meaning all the heat wasn't just working its way down from the head.

The vented cells were 'instantly blister your finger' hot while the others were just too hot to handle. Perhaps the vented cells were the ones that shorted, causing such heat? I wouldn't have thought that venting cells would continue to work, though they clearly were.

I appreciate the feedback, and investigation. Keep it coming.
 
Re: Hotwire Disaster Kills 12 Eneloops

Check all of those battery adapters, I'll bet one melted causing one of the contacts to short to ground (the flashlight), and it was all down hill from there! High resistance carriers could cause the heat, springs and all, that's why FiveMega doesn't use springs.
 
Re: Hotwire Disaster Kills 12 Eneloops

Awesome report! I hope the CPFBI comes to a conclusion soon :)
 
Re: Hotwire Disaster Kills 12 Eneloops

My condolenses to the families of the cells that gave their lives in order for Sed6 to learn from his mistake. :(

Please let me know where/when the services will be.

My uneducated guess is a short within one of more 3AA-1D holders..
 
Re: Hotwire Disaster Kills 12 Eneloops

Obituary?
Calling hours?
Funeral?
:mecry:
 
Re: Hotwire Disaster Kills 12 Eneloops

Nice journalistic writing style, that was an entertaining read.

If I ever felt the body of one of my lights getting hot, I would immediately shut it off and inspect everything. There must have been some serious resistance going on in there.

Regards,
Mark
 
Re: Hotwire Disaster Kills 12 Eneloops

Kai battery adapters have been known to have problems. Those eneloops were roasting in their own juices in battery hell. I hope you can sleep well at night, you murderer.
 
Re: Hotwire Disaster Kills 12 Eneloops

Looking at the style of the report i thought this is a joke, apparently not :poof: Poor Eneloops...

So enloops can handle 10 amps? they drop to below 1.1v dont they?
 
Re: Hotwire Disaster Kills 12 Eneloops

I'd love to contribute something useful, but I can't. Just wanted to say, I really enjoyed reading that post, very nice writing!
 
Re: Hotwire Disaster Kills 12 Eneloops

There are not enough information to conduct a real investigation, so I'll put my speculation here.
It's typical of electrical device designed only for functionality, to be struck from the theory of catastrophys.
In this specific case, it is highly probable that heat buildup caused the disaster.
A proper M@g mod (Al reflector, ceramic bulb socket, teflon wires, glass window, etc.) can barely cope with the heat produced from the bulb.
I believe that contact resistance of the battery adapters added the right quantity of heat that, together with the heat produced from the bulb, initiated the "catastrophy", in this case a thermal meltdown, leading to a possible short-circuit.
I do not put any faith in metal spring contact and switches for current above 5 Amp. My few incandescent mods only use welded cells and solid state switches.
My 2 € cents

Anthony
 
Re: Hotwire Disaster Kills 12 Eneloops

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