Lithium battery failure = boom (I'm okay)

[Majestic]

well i have grey wrapped 'protected' cells , and blue wrapped 'un-protected' cells for DX

Well so much for my theory.

[EldarKinSlayer]

Eskimo thanks for sharing with us and I am glad it didn't hurt more.

[dedmonwakin]

I've had 11.1v li-po batteries explode which sound like a shotgun blast, but not the e-cig, ....yet.(knock on wood) I have noticed in the two occasions when the batteries where nearing explosion, that intense heat emitted from them making it to hot to touch or hold following the cells or wrapping of the cells to expand until it bursts. I'm sure if the e-cig were going to do the same, it'll be time to toss it like a hot grenade. Batteries don't typically go off with out warning, although, often times they seem to fail with out warning.

This is definitely something that needs to be taken with precautions, so if your battery case begins to get hot and you can quickly rule out it's not the atty, launch it as fast as you can, because there is absolutely nothing you can do but keep yourself and others out of harms way.

I'm sure a battery in a metal housing with no room for expansion, heat will generate quite rapidly with an accelerated time to detonate. But I highly doubt that it will explode with such force that you have to be concerned of shrapnel (other than the plastic ash tip or the brass connector flying out.

All of my batteries have PCB's, but that doesn't make me feel totally safe at all. These high voltage batteries are still produced in unregulated quality manufacturing, so pcb failure is just as likely as a battery with out a PCB in my opinion.

[.308]

That's what I've wondered about with these factory e-cig batteries, non of them have protection circuits. I'm sorry, but it's rather annoying having to wait for it...wait for it... wait for it... "OK it's green, quick take it off the charger before it fries!" you know? I see the marketing aspect, people keep having to come back for more batteries about 4 per month sometimes, but come on...

I grow weary of also having to unscrew the damn thing and make sure a drop of juice doesn't get into the battery as well. That's why I started modding, I didn't want the hassle of poorly designed products only holding a couple hours of charge and failing after a week.

[JohnnySmith]

that's a major reason these things will be banned , having an unstable power source so close to the users face.
I wonder what kind off safeguards and standards mobile phones have with their batts.

Still , glad your all ok Eskimoroll. I'm guessing the failed battery was un-protected ?

and don't forget a protected batt will be a millimeter or two longer than the un-protected variety.

I am sure that if they get banned it will be because of the gov being greedy because they loose out on tax money

[tims]

When you buy the cheapest china battery's you can find, with the highest out put this will happen. Top grade battery's cost more for a reason, as the old saying goes you get what you pay for.

Really if your going to do battery mods, buy top grade battery's to run it from day to day. Use the cheap ones just for testing, when you are ready if some thing goes wrong with them.

This is one reason I'm using AA and AAA right now, I never had problems with them before. But I buy top grade ones, also you may have a bad charger. They can and do mess up battery's, so you may want to check that as well.

[Kelemvor]

That's what I've wondered about with these factory e-cig batteries, non of them have protection circuits. I'm sorry, but it's rather annoying having to wait for it...wait for it... wait for it... "OK it's green, quick take it off the charger before it fries!" you know? I see the marketing aspect, people keep having to come back for more batteries about 4 per month sometimes, but come on...

huh? lets check.. kissbox classic, protected, dura /510 protected. chargers all protecting the battery.

i don't know which factory batteries you mean here, maybe it was before my time in vaping back in february.

sometimes "we should keep the church in town" as we say in germany

i heard of some old cigar battery chargers not really shutting of charging 10440 to death. but my chargers all do that correctly.

for max safety i don't charge overnight or with nobody at home. and thats what manufaturers of batteries write in every instruction booklet.

[tornicgr]

In one of my DIY battery mods, that I used four 1.2v NiMH batteries, I added a LM2940-5 regulator to ensure the cut-off of the batteries in case their voltage drops under 2.5v (in total). Also this regulator has the ability to limit the current to MAX 1A !!!! Another measure to ensure steady discharge rate from the batteries !!!

Thanos



(I posted it correctly this time... )

[I am Nico]

ba bang booom !!!!

[Dave Rickey]

There is no PCB protected CR2 on the market. Some of the 2CR2 6V packs are protected, and AW *used* to make a protected CR2 but doesn't anymore (apparently the reduced capacity from shortening the can to make room turned people off on buying them, especially as AW "honestly" rates their batteries for mAh from full charge to shutoff (Ultrafire rates theirs for what you would get if you slowly drained them down to 0V, which gives higher but misleading numbers, Tenergy isn't as bad but still over-rates), so their protected battery had less than half the rating of everyone else's unprotected.

You can buy the PCB's and hook them up to the battery yourself (adds a bit more than 1MM to the length), you can even get them with the leads already soldered on so you just have to tape/glue them to the ends and the load (although if you can't solder, you probably shouldn't be modding). But then you should heat-shrink the whole thing together so it stays put and nothing else shorts the battery.

You can also get the same kind of protection circuits they use in cellphones and other Li-Ion powered devices and make them part of your mod. DO NOT USE THE DISPOSABLE CELL PCB'S AS DEVICE-LEVEL PROTECTION. They aren't designed to outlast the useful life of the cells.

Some of AW's cells include another level of protection (called "Physical Thermal Protection", PTC), an over-temp condition will cause the elements to be physically separated, shutting down the chemical reaction. And *all* of them, even the "unprotected" cells are over-pressure vented in a way that reduces the chances of secondary flameout (vented gases coming out so hot and concentrated they set off other cells).

AW is also the only producer of 3.7V LiMN cells (a safer chemistry that isn't vulnerable to thermal/pressure runaway), but they only have a few sizes (16340, 18500, 18650, and 26500). The downside is that they have about 25% less real capacity than Li-Ion, but unlike the LiFePO4 chemistry (the other safe cell type), they have the same voltage profile and can be charged and used in the same devices (LiFePO4 has a 3.2V base and 3.6V max voltage).

Probably more than you wanted to know. Frankly, 2-cell designs should probably be using LiFePO4 cells, since 6.4V is plenty for that purpose, and even if the only small-diameter LiMN cell is the 16340, it should probably be considered for a device you HOLD IN YOUR HAND 4 INCHES FROM YOUR FACE. Li-Ion batteries have something like 60% of the energy density of TNT, and even if they can't liberate that in a 5kms shockwave, it's an inherently unsafe situation. At a minimum, this stuff should be getting designed in a way that will vent away from the user? How many devices are pointing the positive button-top towards the mouthpiece? That's the direction the FLAMING HOT POISONOUS GAS COMES OUT, if the cells go into thermal runaway.

I'd apologize for the caps, but I think too many people are disregarding safety in how they build their devices. These are not toys, the only electronic DIY I can think of with a higher danger factor is a hand-portable medical or industrial-grade laser. If they were running off of a thermite fuel cell, would you be so casual with them?