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Comment by mitigating | Hacker News Reader

Everyone is aware of the risks, there were a bunch of stories about airplane cell phone fires a few years ago.

What are suggesting people do? Headphones only function while on your head.

I never thought that my wireless headphones had enough juice to fill my house with smoke, to burn for 15 minutes, or result in chemical burns to the user.

They're made of thermoplastic, practically everything plastic burns except for the few things around which are regulated to be impregnated with fire retardants (children's clothes, furniture, etc). Unless what you're holding is made entirely of metal or ceramic, you can be pretty sure that it is some degree of fire risk, if it contains a battery or not.

Last time I checked, the energy densities of modern batteries were approaching that of TNT. Which is insanely worrying to me.

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.

Try googling both: "1999 butter fire" "1991 butter fire"

Wisconsin and France have had notable butter fires. So I guess even butter fires can be bad news.

If you're into foodstuff-related destruction, the other things to search for are "flour explosion" and "molasses disaster"

A lithium ion battery has about 2-3% as much energy per gram as a chocolate bar. The energy density is not what causes safety issues.

> Everyone is aware of the risks

Everyone here, maybe. Almost everyone I know of is certainly not aware of any dangers (or goes with the classic "it will certainly not happen to me, what are the chances of that?").

I still have to remind my relatives not to just throw a charging phone wherever it lands (like under the pillow). The risk of it going off may be small, but the cost would be very high.

I was not aware of these risks. I knew that li-ion batteries were flammable but didn't realize they would malfunction in consumer devices. Now I know!

You weren't around for the Galaxy Note debacle?

I mean, it being not the standard is exactly why it's a debacle, right?

There was a period of months where cell phone fires on planes was all over the news. There's also a massive recall of the Chevy Bolt recently.

>Everyone is aware of the risks, there were a bunch of stories about airplane cell phone fires a few years ago.

No harm warning about these risks on the label, then?

Everyone is aware, so it surely won't hurt the bottom line.

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