If he is faking it they will figure it out pretty quickly. I think you linked the wrong video
My favourite li ion failure video is the cell phone review where they bash the phone with a small sledge hammer till the battery vents and the guy asks his buddy for some febreeze (as if that will make the fumes less toxic)
"I mean it's pretty rare. Some people win the lottery and some people have a flashlight blow up in their' mouth, ya know!"
that hat linked to a USA today website, the video might be posted on YouTube but it seems legit.
That’s one of my favorite li-ion venting videos too. Not too smart to puncture a lipo battery pack.
I don’t have doubts about the legitimacy of the story, but I was surprised that a lithium iron phosphate cell would violently vent and injure the user. These venting scenarios are usually associated with lithium cobalt rechargeable or lithium primaries in series. I guess LiFePO4 cells can’t be considered as safe as we had thought.
I’d like to see a more detailed investigation about this. I haven’t read the CPF thread, but maybe they’re speculating about what exactly happened?
Excuse me while I whip this gif out.
+1 Lights in series are much more dangerous than in parallel. CR123 have always been knows as dangerous. But… it doesn’t matter the make of the cell or the type of cell. I had just two brand new MNKE 26650, that I put in a 2x26650 light and within a couple minutes, one cell was hot as hell, (scary hot) and the other felt like it had never been drawn on. I always check after one or two minutes, when using a new light, or cells I haven’t used before. To me, parallel is safer than Series. Series is asking for trouble. I most always notice one cell much hotter than the other and tell me if I am wrong, I don’t believe protection circuits on cells shut down for heat?
Previously discussed in the ongoing thread, which has more facts and some good practice advice as well:
(page down if the web software just takes you to the top of the thread)
I used to put flashlights in my mouth often, I quit immediately when I started using Lithium batteries.
It was suprisingly hard to break that habit.
Luckily my only light with a bite grip uses NiMH or primary AAAs.
Did anyone see this line in a quote?
“Took the light apart when it got here, because that’s what I do. It came off with a lot of effort. When I went to put it back on, it took a wrench. So now the switch is stuck on the light body. Which is ok, unless the switch breaks. ”
There was something wrong from the get go. The tailcap was put back on WITH A WRENCH! Yikes! Could it be that the cells were compressed, nearly frozen and then turned on and got hot under pressure and oops!?
LiPo (pouch cells) and LiCo (18650 cells) are pretty much the same thing… just a different package.
If this was a solarforce host, how did he get the batteries out if the switch was stuck? something definitely sounds off.
……………………
This streamlight scorpion is marketed to and very popular with LEO’s, and I remember seeing it advertised somewhere that the rubber casing is “great for holding in your mouth when you need both hands free.” 2 CR123’s in series in my mouth? no thanks!
I read through the thread over at the other forum last night.
It seems like a legit thing that happened.
It appears he was fairly new to the ‘flashlight scene’, having only recently joined over there, & had a few posts asking for recommendations on inexpensive lights.
Never having spent much time at the other forum, it gave a good insight into the amount of effort the moderators put in 0:)
pilotdog68, the battery can be removed/inserted by removing the head of the SF lights I have.
TP, the light wasn’t out in the cold truck, he had it with him in the house.
Seems like he’s recovering fine.
No...
The only time there is danger with parallel cells is when they are inserted in the holders. If the voltages are different, then there may be a sudden big current rush to equalize the voltages. Perhaps even so big current that the batteries heat up, or wires between them, plastic may even catch fire. This is easily avoided by only inserting all batteries at once, and only if just fully charged to the same voltage. They are then all typically at 4.2 volts. While the batteries are used the voltage will fall, but will be identical for all batteries. There could perhaps be a problem if you mix chemistries, for instance batteries that may be discharged to 2.5 volts with batteries that can be damaged at that voltage.
When used in series the batteries does not have to have the same voltage when inserted. There will be no sudden current rush if batteries with different voltage are insertes. However if the batteries have different capacity, are unbalanced, then there may be danger when one of the batteries are exhausted long before the other(s). The discharged battery will then act as a resistor in the circuit and warm up and the voltage over the battery may fall dangerously low. And permanently destroy the battery or even cause it to vent suddenly (explode).
Parallel: Same voltage when inserted!!! Safer otherwise.
Series: Same capacity!!! Preferable even exactly the same model and the same age. And charged the same.
the appearance of the burned cells in the video looks like he had two CR123 cells or two 16340 cells in series in the light. As mentioned above its possible they were unprotected and/or one was low or dead thus when he turned the switch on the cells tried to stabilize and BOOM. I never liked using two CR123 ( or RCR123, 16340, or any lithuim, etc.) in series ever in any light, though some companies like “surefire” promotes the practice in some of their lights. Along with the fact there are container loads of these cheap, unsafe knock-off, faulty, ripoff bomb-batteries unloaded here in North America by the ship loads to be bought with no regulation or testing and end up blowing people to little shreds & pieces.
Maybe on the day when they were handing out brains, he was The Last in Line. :bigsmile:
Some factors which could have contributed to the problem…
- The two 16340 LiFePO4 cells were in series, and series is much riskier than a single or parallel config.
- The cells were unprotected.
- The cells were relatively cheap.
- The host had something wrong with its tail threads, and was screwed on with a wrench. This could over-compress the cells, leave bits of aluminum floating around in the host, etc.
- The light appeared to be wrapped in electrical tape or something similar, which would interfere with heat dissipation.
- It’s not known whether the drop-in supported more than 4.2V.
My guess is that the cells probably tried to equalize each other and there may have additionally been a short causing direct-drive on the output. The tape wrapped around the light helped keep the heat in until something caught on fire, and then it blew apart at the weakest point — the damaged tail threads.
This is a large part of why I avoid serial battery configs, or at least make sure to use protected cells for serial configs. Also why I avoid using damaged hosts, and brush out the inside of new hosts to get rid of any stray metal scraps. And why I don’t use cheap batteries. I also tend to avoid P60 designs, since I don’t trust the thermal transfer from the drop-in to the host.
(the only exceptions I have are a LF L2m w/ UV drop-in and 2x18350 protected cells, and a Convoy M2 w/ MT-G2 and 2x18350 protected cells… neither one ever goes anywhere near my face, and I’ve been thinking for months about replacing one and giving away the other)
One thing we can be certain of, if we believe the details given, the owner is not someone that is cautious and safety first when it comes to the use of his tools.
li ion is risky (Im aware it appears to be LiPo)
series li ion increases that risk
poorly modified or improvised tools increases the risk
popping the tool in your mouth increases the potential damage if the worst case scenario happens.
This was a recipe for disaster. If he had cheap nasty cells it only adds to it, ditto for poorly charged states of batteries, I did not include these as we have no statements to say what brand batteries he was using, or if they were out of sync. But given the above, I wouldnt be surprised if these questions were even unknown to the owner.
The danger of websites such as this, the uninformed and unwilling to read will also source some information from here and act on it half cocked. Its their fault dont get me wrong, but its a reality. Warnings and laws etc will do nothing to help, this stuff is often sourced from OS, and the postage service and couriers are poor law enforcement alternatives. About the only law that will result, is an outright banning on the products, anything else is unworkable and unenforceable with any degree of success. I give you the postage workaround sellers used when li on was banned from transit. There was a long thread on it.
They were labelled as Tenergy, and he used a Tenergy-brand charger. No idea if they were balanced.
after looking at the photos of the light more, it looks like it blew the tail switch boot off and “blow-torched” out the end, along with venting out the front (with enough pressure to blow past the plastic emitter support, and burn the dome off while blowing out the lens at the same time. It was probably like a hobby rocket motor igniting in the mouth.
EDIT* - Just found out from the topic the victim posted himself on CPF just recently. The batteries were “Tenergy LiFePo4” cells, and he was using the supplied Tenergy Charger.
His CPF name is “Subalpine” on CPF.
I believe the explosion caused by the fake battery!