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Li-S is already 2.5x the energy density of TNT.

Before you say "petrol", petrol is typically not carried in the form petrol/oxygen fizz and its energy density is therefore zero.

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TNT has actually pretty low energy density - lower than chocolate chip cookies if I remember correctly. It's only used because of its ability to deliver it all in one go - something cookies lack. Energy density alone is a fairly inadequate metric to decide how dangerous some material is, and what precautions to take handling and transporting it.

Just as petrol, cookies have energy density of zero until mixed with oxygen. Just like TNT, or more like black powder, batteries have all components required to yield energy in one enclosure, which is why there are battery explosion videos and no cookie explosion videos.

likely because the logistics of handling and utilising an energy source that can materialise the entirety of its stored energy instantly has some safety concerns.

requiring air is not a limitation, it’s a feature.

I'm saying I'd rather not be near a 100kW-h Na-S battery. Current Li-Po batteries require quite some shielding at tiny a fraction of the energy density if you don't want to burn.

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