When a Lithium ion cell explodes how much damage can it do? :)

E-driver_

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So.. :)

If I abuse a lithium ion cell and make it explode. How much damage can it do?

Will it explode like a bomb or is it more like a small short circuit explosion that mostly just burns me a bit? But I heal? :)

Also, in what circumstances when building a battery might this happen?

Is it when the voltages are different within some of the cells, and I put all the cells in series, or when does this happen?

It is when I solder the bms on or when does most of these explosions occur?
 
Depends on a lot of things ...

Worse case I heard of was some bloke browsing around a retail store. He had a spare, fully charged 18650 cell in his pants pocket with his lose change. The coins connected the positive and negative ends of the cell for a direct short, heated up and set his pants on fire. He fell against a display that then caught fire, then ... you can figure out the rest yourself.
 
https://www.energy-storage.news/investigation-confirms-cause-of-fire-at-teslas-victorian-big-battery-in-australia/
 
E-driver_ said:
If I abuse a lithium ion cell and make it explode. How much damage can it do?
Depends on the energy in it, and the failure mode, and the specific type, brand, model, etc of cell. It's unlikely that pouch cells would explode, or prismatics--most of them only have weak plastic cases that would rupture before exploding. Steel-encased cells that could have a rapid pressure buildup might, if their vents fail.

If it actually explodes there may be shrapnel like a grenade, depends on the force behind it. You'd have to do a web search for individual cell explosions of the specific type of cell you're going to do this to, or actually test it yourself with proper precautions (which I don't recommend).


It's much more likely you'd simply have a fire that you can't extinguish, that rapidly sets everything around it on fire, and burns down the building you're doing this in, killing anyone or anything caught unawares inside.


Dont' abuse them and you won't have to worry about it.



Also, in what circumstances when building a battery might this happen?

None, if you don't abuse them.

If you're building a battery in a way that you expect this kind of thing might happen, I recommend either not building a battery at all, or first reading up on and setting up the precautions against causing such problems.

And don't abuse them.
 
I only had one cell go off on me. During teardown of a battery pack one of the cells shorted out, this cause a hole on the cell. It didnt explode but the fire was comparable to a blow torch. It will keep burning until all the pressure in the cell is exhausted.
I poured water on the cell to keep it and surrounding cells cool. The water will take down the fire but as soon as you remove the water it reflashes. Once the pressure in the cell is gone the fire is out.
This happened on a lifepo4 cell, never had problems with the 18650 cells.
From my expierence taking packs apart and building packs is probably the times where shorts might occur. Probably a good idea to have the packs discharged to a low voltage during those times. Also take your time during teardown of packs, I was rushing when this cell shorted out.
I still use these type of cells on my solder iron and for tire inflators, very safe cells as long as they arent mistreated.


bae cell fire.jpg
 
None, if you don't abuse them.

If you're building a battery in a way that you expect this kind of thing might happen, I recommend either not building a battery at all, or first reading up on and setting up the precautions against causing such problems.

And don't abuse them.

Aha ok.

I am trying to figure out how to build it as safe as possible. So I am just finding out about what all the bad scenarios could arise from. And what they are. So I don't do it.

I have not built a battery before so I am trying to do as much research on the dangers as possible before I try it out.

In the case where I don't abuse them(I will not try to abuse them) what is the most likely scenario where it might go wrong and become dangerous, even for an experienced battery builder? Is it if the cells have slightly different voltage and all of a sudden gets connected to each other?
 
jonyjoe303 said:
Probably a good idea to have the packs discharged to a low voltage during those times.

Aha.

But how can you discharge cells before to a low voltage if you cannot discharge them via an ebike? Is there a way to drain them of charge in some other way?
 
I just use a regular incandescent bulb for discharging packs. If you are working with cells and building your own pack you should at least have an Opus or LiitoKala charger/cycler. Those will allow individual cell charge/discharge.

I've never gotten an 18650 to explode. The best I can do is make them flare rather violently.
 
jonyjoe303 said:
I only had one cell go off on me. During teardown of a battery pack one of the cells shorted out, this cause a hole on the cell. It didnt explode but the fire was comparable to a blow torch. It will keep burning until all the pressure in the cell is exhausted.
I poured water on the cell to keep it and surrounding cells cool. The water will take down the fire but as soon as you remove the water it reflashes. Once the pressure in the cell is gone the fire is out.
This happened on a lifepo4 cell, never had problems with the 18650 cells.
From my expierence taking packs apart and building packs is probably the times where shorts might occur. Probably a good idea to have the packs discharged to a low voltage during those times. Also take your time during teardown of packs, I was rushing when this cell shorted out.
I still use these type of cells on my solder iron and for tire inflators, very safe cells as long as they arent mistreated.


bae cell fire.jpg

Please don't take this as an attack or me calling you wrong, I simply want to clarify. Are you sure that cell that exploded was LiFePO4? They're really not known for doing that, especially on such a small cell that doesn't hold that much energy.

Again, im not calling you wrong. In fact, can you tell us what specific cell that was? So we can avoid that type. I see from the burnt pics it was an A123. Got any more info on it?

EDIT: was it from these?
https://batteryhookup.com/products/emc-12v-module-with-8x-a123-26650?_pos=6&_sid=7827f8663&_ss=r&variant=31275963613316
 
its the same A123 lifepo4 cells, very powerfull high discharge cells. When shorted out they well burn as well as the li-ion cells. I also heard they were safer than li-ion but from first hand expierence they need to be treated just as safely as the li-ion.
 
Hm, who has more knowledge on this to explain why this happened? It's not like I'm abusing cells, far from it, but it picked LiFePO4 because I watched a dozen youtube videos of people shoving nails through them with no effect, some swelling and a bit of smoke at the most. What would cause the aforementioned cell to turn into a firework when they're "not supposed to"?

Probably the answer is that they're lower risk, but not zero risk. Still, annoyed that I did my research and picked these cells for my build so that I don't have to worry about fire, and now I'm worried!!!! lol
 
The distinction between "a very rapidly expanding unquenchable fire" and an explosion is just semantics.

LFP (and LTO) is known to be very safe **in normal usage** but electricity will always be dangerous.

A dead short is potentially fatal for any chemistry.

Overcurrent protection is critical.

The 3.6-3.7Vnominal li-ion chemistries can "explode" just in normal use, especially once past the EoL SoH stage

and so many hobbyists start off with salvage/scrap and just keep using them as they get more and more worn.
 
E-driver_ said:
In the case where I don't abuse them(I will not try to abuse them) what is the most likely scenario where it might go wrong and become dangerous, even for an experienced battery builder? Is it if the cells have slightly different voltage and all of a sudden gets connected to each other?
That specific scenario can't happen if you are correctly testing, matching, marking everything.

You'd know that they were different voltages, and know not to connect them together, perhaps even keep them all in separate boxes or bins.


The way it could happen is if you are not being methodical and careful, but rather being haphazard or not paying attention.


As long as you go step by step, following procedures such as those in various cell-testing and battery-build threads here on ES (I recommend reading as many of them as you can; you'll quickly get a sense of which ones are being methodical and which are not, and so what to do and what not to do), you shouldn't be able to cause a problem.

"Common sense" will protect you from most problems, and attention to detail will take care of a lot of the rest. :)


There isn't really any single most likely scenario, because it depends on the person working on things and how they personally behave and do things.


But the more cells that are involved in an "incident" of whatever kind, the worse the incident is likely to be. Doesn't make it any more likely, as that is up to the person and procedures they choose to follow, but the more energy there is, the worse the effect of causing a problem will be. :flame:
 
harrisonpatm said:
Hm, who has more knowledge on this to explain why this happened? It's not like I'm abusing cells, far from it, but it picked LiFePO4 because I watched a dozen youtube videos of people shoving nails through them with no effect, some swelling and a bit of smoke at the most. What would cause the aforementioned cell to turn into a firework when they're "not supposed to"?

Probably the answer is that they're lower risk, but not zero risk. Still, annoyed that I did my research and picked these cells for my build so that I don't have to worry about fire, and now I'm worried!!!! lol
The above highlighted part is the answer.

Anything that stores enough energy can fail (or be caused to fail) in a way that can release that energy hazardously.

Even a spinning top (gyroscope) can be fatally dangerous, if it is either massive enough or spinning fast enough, and a mechanical failure occurs or is induced that fragments it or causes an extreme sudden drop in RPM (which could do that too, or heat it enough to fail).


Even a plain old lead-acid battery can explode, usually from hydrogen gas buildup inside the casing too rapidly for any vent to release. I've seen a car hood blown off and up quite a ways into the air by this (when someone was trying to jumpstart someone else's car--I don't know which one blew up).

NiMH and NiCd can also do this (almost 3 decades ago I blew up four AAAs by accidentally connecting them backwards, obliterating the plastic casing I'd built them into, and leaving cell shrapnel embedded in various places in the room).


There've been plenty of LiFePO4 failures / fires, some from damage, some from abuse, some from unknown causes; it's safER than the typical cobalt-based lithium cells, but there's no perfectly safe kind of cell that still has energy in it.


As long as the pack is built well of known-good good-quality well-matched cells, with reasonable precautions against damage (mechanical or electrical or environmental), and is used reasonably, not abused, not damaged, not used outside it's limitations, it's unlikely to have a problem.

Stuff can still happen...and you can only do what you can do, so things can still go bad. It's just much less likely given the above, and more likely the less that is done to prevent or mitigate it.
 
Note that the choice of BMS, if used, also will make a difference: There are different kinds, each with different failure modes or potential problems. The cheaper the design (or rather, especially, manufacturing), the less likely it will be trouble-free.

Nothing is perfect, and anything can fail. Periodic checking of the system as a whole can help find problems before they cause other problems. But generally if there is a problem with a battery, the system will behave differently than before (such as dropping range, or less acceleration, etc), and if attention is paid to system behavior, testing can be done to find the cause and fix it before it becomes a serious problem. :)
 
Can a dead 18650 explode? Cell with zero or near zero charge.
I used them for spot weld test. Spot the side, it did some small fizzled and stop. No longer try to spot well the side.
 
Kimchi said:
Can a dead 18650 explode? Cell with zero or near zero charge.
I used them for spot weld test. Spot the side, it did some small fizzled and stop. No longer try to spot well the side.

Assume it can.

I've always liked this video from Big Clive:
https://www.youtube.com/watch?v=tBg4ximDrsk&t=1021s
Aside from his hilarious deadpan when his workbench catches fire, it's a good illustration of the point that even when there's no charge left, you're still dealing with materials that can case pyrotechnics without electricity. I realize that the specific battery in the video that I linked isn't lithium ion, it's still a good point about battery material being used.
 
Kimchi said:
Can a dead 18650 explode? Cell with zero or near zero charge.
I used them for spot weld test. Spot the side, it did some small fizzled and stop. No longer try to spot well the side.

You wouldn't spot weld to the bottom of the cell either if you recognized the electrolyte decomposes when steel in contact with it is over 1000degC.


A simple 18650 from a laptop is capable of burning through stainless steel in the right type of energy release event.
 
Diggs said:
I just use a regular incandescent bulb for discharging packs. If you are working with cells and building your own pack you should at least have an Opus or LiitoKala charger/cycler. Those will allow individual cell charge/discharge.

I've never gotten an 18650 to explode. The best I can do is make them flare rather violently.

Aha ok. They are called Liitokala cycler? or Opus cycler? Some kind of machine/thing that makes battery packs easier to discharge. I get it I think
 
john61ct said:
The 3.6-3.7Vnominal li-ion chemistries can "explode" just in normal use, especially once past the EoL SoH stage

Can this happen in a type of shrapnel-explosion that potentially hurts the person that are near it a lot? Or is that very uncommon? A rapid fire is more common?

A fire might be somewhat mitigated and not allowed to spread by for example having the battery, when building, in like an oven glass jar or something like that I guess?

But an actual explosion could be very bad for the people around it. Allegedly.
 
amberwolf said:
Note that the choice of BMS, if used, also will make a difference: There are different kinds, each with different failure modes or potential problems. The cheaper the design (or rather, especially, manufacturing), the less likely it will be trouble-free.

Aha I did not know this. I thought the whole purpose of those bms:es was to prevent that kind of stuff.
Do you have a type of bms that you prefer for building 52volt batteries at 14s?

I am thinking about doing that my first building project since I don't see the point of building something smaller, which I can get almost at the same price elsewhere. 52volt batteries are expensive though. And that is why I want to try it. Since it seems to work on most 48volt systems also, which I have a few of.

Disclaimer: I will not take any tips of cells or parts for building batteries as actual advice. I know I should talk to a battery expert or something like that :)
 
Diggs said:
I just use a regular incandescent bulb for discharging packs. If you are working with cells and building your own pack you should at least have an Opus or LiitoKala charger/cycler. Those will allow individual cell charge/discharge.

I've never gotten an 18650 to explode. The best I can do is make them flare rather violently.

I have one of these:

https://www.aliexpress.com/item/32661346790.html?spm=a2g0o.order_list.0.0.70ed1802iJNxKn

Looking like the picture below. This is good enough for charge/discharge perhaps?
 

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All battery cells are like a strike anywhere match giving the right circumstances they all catch on fire explode cause multiple fires and cells to explode in there path all kinds of ways.
Lightning in a box.
Luke how do you build your battery packs what sales do you use how do you connect them what are the biggest no-nos.
 
A woman caught on fire due to her 1.5 volt hearing aid battery she had a lot of wax in her ear and she always liked to put perfume on behind her ear alcohol base with the cat hair mixed with the ear wax and the alcohol from her cheap perfume she actually did catch on fire well it was because of her wig polyester you know and she had a moo moo like gown polyester and she was sitting in a polyester chair the whole house went up the only thing that got out was the cat.
 
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