Gasoline is a flammable liquid carcinogen that evaporates into a highly explosive vapor with an ignition temperature lower than the operating temperature of many exhaust system components.
Gasoline is not all that dangerous in the vast majority of failure modes. Li-ion is both corrosive and easier to set on fire which is a real issue for hybrids and aircraft.
The status quo is Lithium-ion batteries which have certainly been known to spontaneously combust or catch on fire. Gasoline, by contrast, is remarkably stable.
Yeah much like a lot of substances it's only explosive in vapor form. I was thinking the top part of a gas tank, some hypothetical, but not likely, scenario. It seems that the danger from both the Lithium battery and a gas tank are about the same. If the car catches fire it will be because of some freak accident.
Lithium batteries are far more explodey than modern gas tanks. Battery fires burn much hotter and faster than "regular" vehicle fires (which are generally just the contents of the vehicle burning, not the fuel).
"The lithium-ion battery in the laptop sitting next to him had ignited, setting his couch on fire. Battery cells were flying all over the living room, leaking acid."
Lithium-ion cells do not contain acid. The electrolyte is composed of salts, solvents, and additives.
Lithium batteries are dangerous in a way gasoline tanks are not: while a punctured tank (say, due to a unlucky collision with a piece of debris or a crash) is dangerous, it does not guarantee a fire or explosion. A punctured lithium cell will almost always burn.
There are also more ways to screw up a battery. Overcharging, manufacturing defects, and so forth. A gas tank is literally a chunk of cast metal with a pump in it.
Additionally, metal fires are severely hard to fight. Gas fires can be extinguished in the usual ways, but a self-oxidizing metal fire require special considerations, and that's if it can be reasonably extinguished at all. That isn't even mentioning the need to de–energize the battery before attempting a rescue.
* "Because the lower the flash point, the more
hazardous the fire risk, flammable electrolyte solvents in Li-ion batteries are more or less
as hazardous as conventional vehicular fuels."
* "Because the narrower the flammability range, the less hazardous the
fire risk, flammable electrolytic solvents in Li-ion batteries are about as hazardous as
conventional vehicular fuels, and certainly less hazardous than hydrogen."
* "Because the lower the minimum ignition temperature, the more hazardous the fire risk,
flammable electrolytic solvents are not as hazardous as conventional vehicular fuels."
* "Because the lower the minimum spark energy, the
more hazardous the fire risk, flammable electrolytic solvents are probably about as
hazardous as conventional vehicular fuels."
* "Because the lower the maximum flame temperature the lower
the exposure risk (skin burns) to fire, electrolytic solvents are expected to pose no more
of a severe risk to burn injuries than conventional vehicular fuels, gasoline and diesel."
* "Because of the probable similarity in the magnitude of the maximum flame temperatures,
if the combustion of the electrolytic solvents were confined, the resulting overpressure
that could build up would maximize at about the same levels as for the other flammable
fuels, meaning that the burst damage that would result from Li-ion explosions would also
be comparable to that from conventional vehicular fuels."
* "The thermal energy expected to be released upon initiation and combustion of the
electrolytic solvents would be less than that of gasoline and diesel fuel."
I would disagree about lithium ion batteries being more dangerous - gasoline is far more energy dense for one. A slower release is actually a good thing for safety compared to the alternative, a very fast intense one. Besides, just a single mode of failure is not an apt comparison.
- You cannot create a fuel air bomb by throwing lithium ion batteries into your basement and igniting it when the concentration is correct.
- You cannot suffer carbon monoxide poisoning from lithium ion batteries.
It’s worth considering the status quo of ICE and gasoline fueled mechanical infrastructure which certainly has plenty of casualties and human health problems all throughout the lifecycle. In fact, early on I remember reading that people used to think cars should have only so much fuel in them because they are mobile bombs in people’s homes. But the dangers come from the emissions too and when gas tankers get in accidents and leak fuel into our environment.
Lithium batteries in consumer electronics are not really engineered for a ton of safety but for rapid time to market which is certainly not what I’d like to see for very long. And while shipping lithium batteries a warning label needs to be attached but shipping gasoline and lighter fluid requires special permits and must be transported isolated with certain guarantees by law.
In this respect our current market has deemed lithium batteries to be far safer than gasoline without much need for regulatory pressure to do so.
Lithium Ion batteries are dangerous in general. I think they are more dangerous than gasoline: if I puncture my gas tank with an awl it doesn't explode in a 2000degC fire for 4 hours. It is scary, but necessary to adopt new tech IMHO, kinda like how the first Model T's could break your arm when you started them (by turning the crank).
> I could make the argument that fuels that burn are unsuitable for automobiles which crash into each other frequently.
Lithium ion batteries don't like crashing into each other either. The article mentioned that lithium sulfide batteries degrade differently than lithium ion, so fires as a result of heavy use may be reduced, but fires as a result of unscheduled disassembly seem likely, and could be worse than fuel --- you can dump fuel or circle to use it up, but you can't (probably) dump batteries, so you're always going to have lithium available. Not sure if the lithium sulfur compounds are less flamible than the compounds found in lithium ion.
Gasoline just burns. It takes a very specific state to get it to explode.
Not that I'm recommending it, but you could fill a coffee can with gasoline and light it on fire and with only minimum care, be completely safe.
Do the same with an equivalent-energy amount of lithium batteries and you better have a good pair of running shoes.
Go watch some youtube videos of exploding laptops.
The latest big MacBook battery has 100 watt hours of energy fully charged.
A gallon of gasoline has 33,000 watt hours of energy.
So that macbook's battery has 2.3 teaspoons, about 1 centimeter cubed, or 11 mL equivalent energy of gasoline. I have spilled that much gas on my shoe and not given it a second thought. Another way to put it is a laptop battery has about as much energy in it as a shot of vodka.
I'll happily store many bottles of liquor in the cupboard without a thought of the fire risk.
A lead-acid battery has enough power to start a fire however it is itself not particularly flammable. The danger with EV batteries isn’t that they have enough energy to cause an electrical fire, it’s that they are themselves quite flammable.
It's pretty well known that gasoline is a fire risk... that's kind of how ICE engines work. Lithium-ion batteries come in a variety of different chemistries and some, e.g. LiFePo4, are not much of a fire risk at all.
So, yes, if you puncture the lithium cells you may put yourself at risk. You're also at risk if you puncture a gasoline tank (worse if you're talking something like hydrogen).
Note: Tesla does not, AFAIK, use LiFePo4 cells. Additionally one of the big challenges is that LiFePo4 cells are less energy dense than other lithium chemistries.
The energy densities of modern batteries are a couple factors lower than that of gasoline, and much lower than TNT. Gasoline is incredibly energy-dense, but its energy density is comparable to butter. Do you worry about sticks of butter exploding on you? No, you don't. Gasoline is dangerous because it really likes to evaporate and the mixture of gasoline fumes and air ignites at the slightest provocation. Batteries are dangerous because they can go into thermal runaway from an internal short if the barrier between the electrodes fails. The energy density is not what matters here.
Lithium batteries typically don't contain acid.
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