When it comes to devices where does the true responsibility for safety rest

[Mooch]

Perfect timing, I uploaded this earlier today. Just a bit of background info...

Li-Ion Battery Chemistries - What are the differences in their safety? | E-Cigarette Forum

 

[Marc411]

Perfect timing...I uploaded this earlier today...

Li-Ion Battery Chemistries - What are the differences in their safety? | E-Cigarette Forum

Always great timing Mooch thanks! I got the alert earlier, read it and then it got bookmarked.

 

[suprtrkr]

I thought one was more prone to flame, however, I'm thinking of the physics of battery design itself.

You have a tube sealed on one end, the battery chemistry and whatnot inside, and then on the other end you have a plug that becomes the positive. Yes, they start venting gas and that gas building up is dangerous. However, they also seem to eventually blow apart as the plug gets pushed out. With your open/closed fist analogy, there is almost always a closed fist around the battery in a mod, at least on the positive and negative ends, otherwise you would have battery rattle.

If you snug up a battery inside a mod, that's a pretty tight enclosure on the two directions that seem to be most important. I'm fairly certain a 2mm split second expansion in the length of the battery would be enough to blow the button end off of most mods.

I could be wrong though, I haven't looked into any of it. Just thoughts after watching the video.

Interesting. The mechanics of threading are well understood, though, so stripping force can be calculated. Still, what pushes the plug out, if not gas pressure? Are we arguing semantics?

 

[suprtrkr]

Perfect timing, I uploaded this earlier today. Just a bit of background info...

Li-Ion Battery Chemistries - What are the differences in their safety? | E-Cigarette Forum

Thanks, @Mooch

 

[Lessifer]

Perfect timing, I uploaded this earlier today. Just a bit of background info...

Li-Ion Battery Chemistries - What are the differences in their safety? | E-Cigarette Forum

Thanks Mooch!

Interesting. The mechanics of threading are well understood, though, so stripping force can be calculated. Still, what pushes the plug out, if not gas pressure? Are we arguing semantics?

It is no doubt the gas pressure, at least initially that pushes the plug out. I'm just wondering if that will always happen anyway, regardless of the venting space available in the mod itself.

Imagine a vice grip, made for some reason of a soft metal like copper, and you place a battery inside end to end. Is the force of the gas buildup inside the battery itself enough to pop the plug and strip the copper threads of the vice grip?

 

[suprtrkr]

Thanks Mooch!

It is no doubt the gas pressure, at least initially that pushes the plug out. I'm just wondering if that will always happen anyway, regardless of the venting space available in the mod itself.

Imagine a vice grip, made for some reason of a soft metal like copper, and you place a battery inside end to end. Is the force of the gas buildup inside the battery itself enough to pop the plug and strip the copper threads of the vice grip?

I can't answer that without doing the calculation (and making some assumptions, like type of copper in the vice grip, size of the vice grip, thread of the jaw adjustment screw, leverage moment in the jaws, etc). But I take your point. It seems to me the answer here is, good venting can obviate or reduce the danger in a vent, and not much of anything except not being there will save you in case of runaway.

EDIT: I say that because good venting will reduce tube pressure, and thus lessen to total force loading on the mod threads... Whether or not it would be enough, no way to calculate except in individual circumstances.

 

[Lessifer]

I can't answer that without doing the calculation (and making some assumptions, like type of copper in the vice grip, size of the vice grip, thread of the jaw adjustment screw, leverage moment in the jaws, etc). But I take your point. It seems to me the answer here is, good venting can obviate or reduce the danger in a vent, and not much of anything except not being there will save you in case of runaway.

EDIT: I say that because good venting will reduce tube pressure, and thus lessen to total force loading on the mod threads... Whether or not it would be enough, no way to calculate except in individual circumstances.

I was thinking threading like that on a copper tube mod, and just said vice grips so there would be no question of ample venting. Just wondering if the pop of the plug is enough to blow the switch off a tube mod, regardless of the gasses.

Anyway, I'm feeling a little better about the spring in my REO, which also has the giant hole for gasses to exit from.

 

[Canadian_Vaper]

You just can't count on a B&M to give good advice these days.

Definitely agree, went to one last summer or fall forget, the girl had a subox mini not that it matters, asked if they had kanthal, she replied I don't think we carry that tank.... Maybe she was thinking kanger? like her mod lol... Explained to her that it was wire, looked at me strange, told her it's what her coils were made out of, pretty much just walked out of the shop after that....

How the hell does someone that doesn't know what kanthal is get a job at a vape shop? Is she going to teach people battery safety or know not to sell a hybrid mech and a tank....

 

[suprtrkr]

I was thinking threading like that on a copper tube mod, and just said vice grips so there would be no question of ample venting. Just wondering if the pop of the plug is enough to blow the switch off a tube mod, regardless of the gasses.

Anyway, I'm feeling a little better about the spring in my REO, which also has the giant hole for gasses to exit from.

Again, depends on the copper. Pure red copper (C110) is very soft. You might be able to strip those threads by hand and definitely with a hammer and punch. Unfortunately, C110 has the best conductivity but is fearsome difficult to get clean machining and hard to work. Most "Copper" mods are build out of C145 copper, a copper and tellurium alloy. It has about 85% of the conductivity of C110, and about 80% of the strength and machineability of hard brasses, perhaps 65-70% of that of marine grade bronzes. That's a lot tougher and would hold threads better. And yes, I feel pretty good about my LP/SL

 

[YoursTruli]

Perfect timing, I uploaded this earlier today. Just a bit of background info...

Li-Ion Battery Chemistries - What are the differences in their safety? | E-Cigarette Forum

Thanks @Mooch!
I have a question. In this article you say when speaking of thermal runaway:

"While it can be quite violent, this isn't the explosion seen in a few videos that have made their way through the vaping groups and forums. Those explosions happen when a device doesn't have a pop off side panel or large open areas for the pressure to escape. The device holds back the gases for a bit but eventually it can't withstand the increasing pressure and it explodes.

It is quite difficult, but not impossible, to bring the temperature of a battery up quickly enough to go into thermal runaway without it venting first. About the only way to do it is with a short circuit.

Both venting and thermal runaway can take hours to occur or they can happen very quickly. You will typically be able to feel a battery getting hot before it vents but do not assume the same for preventing thermal runaway. That depends on a very, very fast rise in temperature, happening before the battery can vent. You might not feel the battery get hot first."


I am not sure I understand. You say the mods are blowing apart from vented gas build up but also a thermal runaway event can happen with no venting.
Could a dead short in a mech mod cause the battery to go straight into thermal runaway and explode inside the mod without venting first also cause the mod to blow apart (from the force of the battery exploding) with little to no warning to the user?

 

[suprtrkr]

Thanks @Mooch!
I have a question. In this article you say when speaking of thermal runaway:

"While it can be quite violent, this isn't the explosion seen in a few videos that have made their way through the vaping groups and forums. Those explosions happen when a device doesn't have a pop off side panel or large open areas for the pressure to escape. The device holds back the gases for a bit but eventually it can't withstand the increasing pressure and it explodes.

It is quite difficult, but not impossible, to bring the temperature of a battery up quickly enough to go into thermal runaway without it venting first. About the only way to do it is with a short circuit.

Both venting and thermal runaway can take hours to occur or they can happen very quickly. You will typically be able to feel a battery getting hot before it vents but do not assume the same for preventing thermal runaway. That depends on a very, very fast rise in temperature, happening before the battery can vent. You might not feel the battery get hot first."


I am not sure I understand. You say the mods are blowing apart from vented gas build up but also a thermal runaway event can happen with no venting.
Could a dead short in a mech mod cause the battery to go straight into thermal runaway and explode inside the mod without venting first also cause the mod to blow apart (from the force of the battery exploding) with little to no warning to the user?

Perhaps I misunderstood when I read his post, but that is the impression I took away.

 

[Bad Ninja]

Thanks @Mooch!
I have a question. In this article you say when speaking of thermal runaway:

"While it can be quite violent, this isn't the explosion seen in a few videos that have made their way through the vaping groups and forums. Those explosions happen when a device doesn't have a pop off side panel or large open areas for the pressure to escape. The device holds back the gases for a bit but eventually it can't withstand the increasing pressure and it explodes.

It is quite difficult, but not impossible, to bring the temperature of a battery up quickly enough to go into thermal runaway without it venting first. About the only way to do it is with a short circuit.

Both venting and thermal runaway can take hours to occur or they can happen very quickly. You will typically be able to feel a battery getting hot before it vents but do not assume the same for preventing thermal runaway. That depends on a very, very fast rise in temperature, happening before the battery can vent. You might not feel the battery get hot first."


I am not sure I understand. You say the mods are blowing apart from vented gas build up but also a thermal runaway event can happen with no venting.
Could a dead short in a mech mod cause the battery to go straight into thermal runaway and explode inside the mod without venting first also cause the mod to blow apart (from the force of the battery exploding) with little to no warning to the user?

Yes.
It is definitely possible.

 

[YoursTruli]

Thank you @Bad Ninja

 

[entropy1049]

Thanks @Mooch!
I have a question.
I am not sure I understand. You say the mods are blowing apart from vented gas build up but also a thermal runaway event can happen with no venting.
Could a dead short in a mech mod cause the battery to go straight into thermal runaway and explode inside the mod without venting first also cause the mod to blow apart (from the force of the battery exploding) with little to no warning to the user?

Yes. A battery venting is failing in the way the manufacturer hopes it will. It's less catastrophic than explosion. It is designed to vent should it get too warm.

Sometimes the failure causes the heat build up to happen too quickly for the venting process to occur, like in the case of a hard short. These situations lead to thermal runaway and explosion.

Hopefully what you're asking.

 

[Mooch]

Thanks @Mooch!
I have a question. In this article you say when speaking of thermal runaway:

"While it can be quite violent, this isn't the explosion seen in a few videos that have made their way through the vaping groups and forums. Those explosions happen when a device doesn't have a pop off side panel or large open areas for the pressure to escape. The device holds back the gases for a bit but eventually it can't withstand the increasing pressure and it explodes.

It is quite difficult, but not impossible, to bring the temperature of a battery up quickly enough to go into thermal runaway without it venting first. About the only way to do it is with a short circuit.

Both venting and thermal runaway can take hours to occur or they can happen very quickly. You will typically be able to feel a battery getting hot before it vents but do not assume the same for preventing thermal runaway. That depends on a very, very fast rise in temperature, happening before the battery can vent. You might not feel the battery get hot first."


I am not sure I understand. You say the mods are blowing apart from vented gas build up but also a thermal runaway event can happen with no venting.
Could a dead short in a mech mod cause the battery to go straight into thermal runaway and explode inside the mod without venting first also cause the mod to blow apart (from the force of the battery exploding) with little to no warning to the user?

Yes, thermal runaway can happen without venting though some might argue that when a battery bursts, that is venting. The mods blow up not from a venting event, which involves little gas, but the extraordinary amounts of gas produced in runaway.

Yes, a dead short can go almost instantly to bursting of the battery without venting happning first.

 

[Marc411]

So as long as you hit this thread Mooch and going back to the original question.

Assuming the device a good and the build is as close to perfect as a human can get what are the capabilities of mods set up like this (below) if people attempt to use the max wattage with lets say a .1 or .2 ohm build. I know the battery sag on my 26650 at .3 ohms and 39W is fairly significant.

Dual 18650 devices rated for 200W
Single 26650 rated for 100W
Single 18650 rated for 90W

 

[YoursTruli]

Thank you guys for helping me to better understand I have wondered about this for a while.

 

[Mooch]

So as long as you hit this thread Mooch and going back to the original question.

Assuming the device a good and the build is as close to perfect as a human can get what are the capabilities of mods set up like this (below) if people attempt to use the max wattage with lets say a .1 or .2 ohm build. I know the battery sag on my 26650 at .3 ohms and 39W is fairly significant.

Dual 18650 devices rated for 200W
Single 26650 rated for 100W
Single 18650 rated for 90W

Pardon me, are you asking what batteries are best for these setups? You can check my 26650 grades and pulse info for the best 26650 for high wattage. The best 18650 at 90W will be the same as the best for 100Wx2. For these it all depends on whether you want lowest operating temperature, longest running time, or highest voltage under load.

 

[Mike Weatherford Jr]

Let me explain how I feel about safety. Just about everything has safety mechanisms these days, even cars can detect a pending frontal collision and react by either cutting the engine or braking on its own. Firearms, as we all know, have safety mechanisms. I'm sure many of us have vapes that'll cut off if the battery gets too hot. In my life, I am the only safety - I study things before I do them, learn the ways things are meant to be to maintain my own well-being. Whether it be with my vape, my car, a firearm, even a pan full of bacon, I am the only one I can trust to keep myself safe. If something goes horribly wrong when I put my vape to my lips, it won't be UD and Tobh's fault UNLESS it was a defect in the product. Now if I throw my 40 amp batteries I use for my work flashlight into my Bishop and blow my face to Hong Kong, that's all my fault - I know better.

Sent from my LGLS740 using Tapatalk

 

[Marc411]

Sorry Mooch for being vague or maybe just a little dense. My question is this, even with quality batteries are OEM's putting users at risk because they are releasing devices that at the max wattage are going to cause batteries to fail? Example:

Someone picks up a 200W device and places a .2 ohm build into it and ramps it up to 200W on a set of 25R's.

What type of run time can they expect? Can they easily push the battery past it's limits and cause the cell to go thermal?

Each of the devices listed below seem to exceed a battery (s) useable CDR but have been released to the open market.

Dual 18650 devices maxed out @ 200W
Single 26650 devices maxed out @ 100W
Single 18650 devices maxed out @ 90W