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Maybe a stupid question, but does a Li-ion battery need to be charged in order to burn like this? I'm not talking about the batteries that start the fire. Obv

Maybe a stupid question, but does a Li-ion battery need to be charged in order to burn like this? I'm not talking about the batteries that start the fire. Obviously they won't cause an electrical fire if they're not charged. I'm talking about the other batteries nearby that get heated up by the initial fire.

philipkglass 5y ago
Most lithium ion batteries contain mixtures of liquid organic carbonates as electrolytes. They range from moderately to very flammable. Here's some vendor information on dimethyl carbonate, one of the more flammable electrolyte components: https://smc-global.com/dimethyl-carbonate/ https://smc-global.com/dimethyl-carbonate/ https://smc-global.com/wp-content/uploads/2021/04/M3574_DIMETHYL_CARBONATE_616-38-6_GHS_01262021.pdf https://smc-global.com/wp-content/uploads/2021/04/M3574_DIME... These liquids can burn regardless of the battery state of charge.
- userbinator 5y ago
  Incidentally, besides the flammability, the electrolyte is otherwise quite harmless. It's comparable to ether, alcohol, or acetone.
  - snovv_crash 5y ago
    There are other components in the battery which are both toxic and corrosive to electronics. Please be careful of any broken batteries and if there is a fire don't breath the fumes!
- ajross 5y ago
  This is true, but pretty badly misstating the risk analysis. Lithium electrolytes are, on the whole, "flammable" in exactly the same way that things like grain shipments are flammable. It's a real risk, and requires engineering to address. They aren't remotely "dangerous" materials.
- hermitdev 5y ago
  Sort of like how a transformer explosion is typically a lot worse due to the oil used to cool larger transformers. The oil is great because it allows for heat transfer well, fits into all the nooks and crannies and isn't conductive to electricity. But, the oil is still flammable. And then, trying to put out the flames, the combination of electricity and oil makes using water a very bad idea.
Nasrudith 5y ago
Yes - even Lithium Ion batteries which are practically dead may combust if the pouch is pierced (in pouch based ones of course). I recall vaguely shipping standard operating procedure of around 10% charge for bulk batteries and 50% charge for electronics which contain them but don't quote me on those numbers. But either way more energy means bigger, more, and longer lasting flames.
luma 5y ago
They cannot be fully discharged without permanently damaging the cells, so Li-ion batteries are always shipped with some charge.

philipkglass 5y ago

Most lithium ion batteries contain mixtures of liquid organic carbonates as electrolytes. They range from moderately to very flammable. Here's some vendor information on dimethyl carbonate, one of the more flammable electrolyte components: https://smc-global.com/dimethyl-carbonate/ https://smc-global.com/dimethyl-carbonate/ https://smc-global.com/wp-content/uploads/2021/04/M3574_DIMETHYL_CARBONATE_616-38-6_GHS_01262021.pdf https://smc-global.com/wp-content/uploads/2021/04/M3574_DIME... These liquids can burn regardless of the battery state of charge.

userbinator 5y ago
Incidentally, besides the flammability, the electrolyte is otherwise quite harmless. It's comparable to ether, alcohol, or acetone.
- snovv_crash 5y ago
  There are other components in the battery which are both toxic and corrosive to electronics. Please be careful of any broken batteries and if there is a fire don't breath the fumes!
ajross 5y ago
This is true, but pretty badly misstating the risk analysis. Lithium electrolytes are, on the whole, "flammable" in exactly the same way that things like grain shipments are flammable. It's a real risk, and requires engineering to address. They aren't remotely "dangerous" materials.
hermitdev 5y ago
Sort of like how a transformer explosion is typically a lot worse due to the oil used to cool larger transformers. The oil is great because it allows for heat transfer well, fits into all the nooks and crannies and isn't conductive to electricity. But, the oil is still flammable. And then, trying to put out the flames, the combination of electricity and oil makes using water a very bad idea.

Nasrudith 5y ago

Yes - even Lithium Ion batteries which are practically dead may combust if the pouch is pierced (in pouch based ones of course). I recall vaguely shipping standard operating procedure of around 10% charge for bulk batteries and 50% charge for electronics which contain them but don't quote me on those numbers. But either way more energy means bigger, more, and longer lasting flames.

luma 5y ago

They cannot be fully discharged without permanently damaging the cells, so Li-ion batteries are always shipped with some charge.