I was doing some electronics repairs, and accidentally punctured a small (mobile phone capacity) lithium-ion cell battery with a metal spudger.

At first, I hadn't realised I punctured the batteries - I noticed a funny burning smell, and I was like...huh? I turned the battery over, noticed some curls of smoke coming up, and smelt the burning smell again. That's when I was like, oh...c*ap....I disposed of the battery right away.

I feel fine now - no respiratory distress, or coughing, or anything of the sort. I've just rinsed out my eyes my clean water. (In hindsight, I probably should have done it immediately after disposing of the battery).

However, reading through MSDS for lithium ion batteries is quite a sobering read:


It's a Sunday, may see if I can pop into a medical centre later - not sure if this warrants heading into hospital's emergency department for.

However, my question is - has anybody here had any experience with lithium-ion cells? How hazardous exactly are the fumes if you puncture it? What exactly are the fumes/burning smell? (As in, is it lithium reaction with air, or some other by-product?)

Any residual effects or symptoms I should be very wary of? (Basically, if you see X, go to emergency etc.).

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    \$\begingroup\$ search 'lithium ion battery fire' on youtube and you'll see where the real danger of close proximity to a punctured cell is. \$\endgroup\$ Commented Jun 21, 2015 at 2:33
  • \$\begingroup\$ candlepowerforums.com/vb/… certainly keep an eye on things. \$\endgroup\$ Commented Jun 21, 2015 at 12:33

2 Answers 2


Slightly more to-the-point answer concerning the specific materials found in lithium ion batteries:

Lithium metal

Lithium is going to be the number one danger when opening a lithium ion battery. If you get any of it on your skin, the lithium will react with moisture on the skin and ignite more or less on impact, at very high temperature. Counterintuitively, larger amounts of lithium are less dangerous as the hydrogen and other gases produced form a little blanket between the reaction and you. Small specks of lithium can embed themselves on your skin and cause tiny third-degree burns. Lithium dust in your airways can cause havok as well, although the amount needed to really get into trouble is very unlikely to come out of a battery. Only a few types of lithium (ion) batteries contain lithium metal.

Lithium is psychoactive, but you need fairly specific forms of it to be able to absorb this.


This is what you smell when dealing with a bad lithium ion battery. The solvents have gotten out. These are actually mostly fine; if you've ever done the brilliantly stupid thing of washing paint stains off your hands with paint thinner, this is about the kind of solvent we're dealing with. They don't combust into particularly bad compounds either, so burning fumes are reasonably safe to deal with.

Fluoride compounds

This is the second big, big red flag. The specific MSDS you supplied has LiPF6 listed, some batteries have even nastier fluorine compounds. These fluorine compounds are generally not stable in air or water and break down to form hydrofluoric acid which is incredibly corrosive. If you breathe in fluorine compounds, they form this acid in your lungs and cause fluid to build up in your lungs, causing shortness of breath. As mentioned in the comments, HF burns are actually painless (as opposed to HCl burns), but still acutely dangerous.

Other compounds

Important to note is that during combustion of the plastics used to make various parts of the battery (sleeve, polymer dielectrics, etc.), there is a chance of small amounts of hydrogen cyanide and chlorine compounds to be emitted. Chlorine compounds form hydrochloric acid in your lungs, whereas cyanide is very potently poisonous. In a well-ventilated room these chemicals aren't particularly harmful, but especially hydrogen cyanide can be a real problem in an unventilated room as it's odorless. Therefore it's very important to always ventilate any combustion reaction involving (long) hydrocarbons.

Medical advice

Never solicit medical advice, or infer any medical advice from EE.SE. If you're at all concerned about what happened, just go see a doctor. He will be able to conclusively tell you if you've suffered any lung (or other) damage from your accident.

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    \$\begingroup\$ Re, "hydrofluoric acid which is incredibly corrosive," AND it's poisonous, and it acts on nerves so quickly that you feel nothing when you are exposed to it even though it is burning into your skin or lungs. \$\endgroup\$ Commented Jun 21, 2015 at 21:18
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    \$\begingroup\$ @jameslarge: Thanks for the pointer; I was kind of automatically equating HF to hydrochloric/phosphoric/nitric/sulphuric acid, but you're totally right. HF causes painless burns and, surprisingly, it is actually considered a weak acid. Weak acid in the chemical sense, it's still incredibly potent. \$\endgroup\$
    – user36129
    Commented Jun 22, 2015 at 6:44
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    \$\begingroup\$ Some people can smell HCN as almonds. \$\endgroup\$ Commented Mar 24, 2016 at 15:21
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    \$\begingroup\$ Hydrofluoric acid is one of the few acids that can actually dissolve glass! It can eat into your skin in a horrible way. \$\endgroup\$ Commented Aug 6, 2017 at 17:38
  • \$\begingroup\$ If it was such a hazard, they would not allow to use it or write big warnings. I have just punctured a battery with a utility knife and a white smoke came out of it with a good sweet smell. \$\endgroup\$
    – ronenfe
    Commented Dec 10, 2019 at 23:03

Long term you're definitely going to die (of something).

You say you read the MSDS, but I didn't see a link. I looked at the MSDS of a Saft battery - nothing looks all that bad to me, just irritant and corrosive effects- nothing carcinogenic, no neurotoxins or other really bad stuff. The MSDS says for normal exposure to the innards (you didn't eat the battery or have stuff spray in your eye) "In severe cases obtain medical attention". You can judge whether this MSDS applies to you and if your case is "severe".

I've cracked up Li-on batteries deliberately to see what kind of junk was being foisted off on us.. and I'm still okay (more or less). But then I used to play with blobs of mercury metal and melt & pour lead in big open cauldrons (to make gamma ray shields for nuclear applications).

  • \$\begingroup\$ I forgot to add the link, added that now. Thanks, ok, yeah, it's the long-term effects that I was freaked out about. I "feel" fine, so I think I should be ok. No point wasting emergency dept time. Lol, mercury fumes? Yowsers, that sounds...hardcore. \$\endgroup\$
    – user37872
    Commented Jun 21, 2015 at 11:57
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    \$\begingroup\$ Cracking open lithium ion batteries is a super bad idea. \$\endgroup\$ Commented Jun 21, 2015 at 12:34
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    \$\begingroup\$ "...play with blobs of mercury metal and melt & pour lead in big open cauldrons (to make gamma ray shields for nuclear applications)" just the kind of experiments that led to this. Now I begin to understand your astounding answer rate! ;-) \$\endgroup\$ Commented Jun 21, 2015 at 13:07
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    \$\begingroup\$ @ScottSeidman Not at all recommended for people who are not professionals. In this case, Internet rumors had it that the supplier was recycling used laptop 18650 cells and selling them as new. They were not- merely selling really badly-made product and unabashedly lying about the mAh capacity. I half expected to find an AA or AAA cell inside, matryoshka doll style. \$\endgroup\$ Commented Jun 21, 2015 at 14:52
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    \$\begingroup\$ @SpehroPefhany Oh, like this or this? \$\endgroup\$
    – Bob
    Commented Jun 22, 2015 at 9:58

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