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Comment by thatcat | Hacker News Reader

This is an unreasonable standard that doesn't hold true for gasoline or other fuels.

The byproduct of having something that has a high energy density is that it has a lot of energy to dissipate when things fail.

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Gasoline alone does not contain extractable chemical energy. Gasoline mixed with oxygen does, though, and that mixture makes a pretty good bomb if you have any amount of it, like most strong reducers mixed with strong oxidizers. Liquid fuels may burn if they are exposed to air above their flash point and a flame exists, but they will not explode like a bomb.

Unless you mix a bit of it with a lot of air, gasoline is surprisingly quiescent.

Yes and no. Yes it is an unreasonable standard of safety for cars (and maybe planes) today. No, it's unreasonable to allow things to blow up in close quarters like on a laptop.

I don't get how a laptop exploding is less acceptable than a car or an airplane exploding.

Because a car won't explode due to malfunction, and not on your reproductive organs.

That makes no sense. Why do you think motorcycles are called "crotch rockets"?

For their speed/weight ratio? Certainly not because they typically don't explode... Outside of Schwarzenegger films.

Contrary to what Hollywood tells us, mopeds, bicycles, cars, trucks, motorcycles, and boats almost never explode (Airplanes occasionally explode. Rockets frequently explode.) They certainly don't explode as frequently as your average laptop battery.

Anytime someone blithely talks about including an oxidizer (or oxygen) into the mix, it's good to remember all of what you just said. Highly reactive elements and oxygen are far more scary in general, and given enough oxygen pretty much everything becomes highly reactive.

That being said, while a car won't explode, they sure as hell do burn.

In cars the flammable bits are normally fairly separated from the passengers so if the engine goes up in flames you can just get out and watch. Laptops less so.

Of course, you may find that the impact which caused the fire has also rearranged those fairly separated parts. Still, that's predicated on a crash, which is at the very least, fair warning that more things are likely to be going wrong. "My laptop seems war- OH GOD", less so.

Cars are an absolute necessity of what we consider to be the modern world, while laptops with lithium-air batteries could not possibly be considered that critical?

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