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Comment by supermatt | Hacker News Reader

Or a McDonalds medium fries?

EDIT: doh, just realised you were comparing with other forms of damage. That said, I think its truly amazing that a snack has the same energy as a nasty car crash. Mind blown.

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To me it is hard to visualize how much damage the total energy gained from digesting chemical bonds of food could do to an airplane. I can better visualize the damage that could be done by a highway car crash or detonating a handful of TNT in an airplane.

These counterfactual comparisons are a slippery slope and not as helpful as you think. I hardly think that you, I, or most others have an intuitive understanding for what happens when a 1 gram meteor hits earth. Have you ever witnessed that?

The average failure state of a battery is not similar to detonating a handful of TNT on an airplane, which is a more instantaneous explosion. Sure, some battery failure states are violent and would unquestionably be a cause for an airplane to call a mayday and land, but something like puncturing a soft-cell battery is still a slower release than TNT.

We should just expect people to get better at understanding useful units — I'd prefer someone learns Wh since it is indeed a useful metric—kWh is the usual major unit of energy at home, and Wh is just smaller than that.

I was trying to guesstimate a theoretical upper-bound on the damage. Looking at youtubes online, it seems a labtop battery explosion is still scary and more like a handful of firecrackers than TNT, but what actually seems worse is that the explosion is followed by the labtop being on fire and producing subsequent smaller explosions. So the worse case is that the fire ignites other stuff in the plane, which includes other lithium batteries.

That is, 100 Wh = 86 kcal.

Enough energy to heat 1 kg of water by 86°C (or 86 kg of water by 1°C).

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