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Yea. Batteries are a tough problem. A battery with the energy density of TNT would be great. Not sure I'd want it sitting on my lap...
by jwilliams 12y ago
Yea. Batteries are a tough problem.
A battery with the energy density of TNT would be great. Not sure I'd want it sitting on my lap...
- ISL 12y agoYou already do. Lithium-ion batteries have 25-50% the energy density of TNT. https://en.wikipedia.org/wiki/Energy_density https://en.wikipedia.org/wiki/Energy_density (to fill in the missing volumetric density entry, you need to know that TNT has density 1.7 g/cc)
- jwilliams 12y agoThink you're referencing Lithium (non-rechargeable) batteries. Lithium Ion is much lower. Even then, they still occasionally overheat and very occasionally catch on fire. I think my original point still stands.
- brohee 12y agoAt 4.6MJ/kg TNT is fairly low energy density compared to e.g. Jet Fuel at 43MJ/kg. This still makes me think the future may be in fuel cells more than it is in batteries, but by now we were supposed to have fuel cell powered cellphones and laptops and it didn't came to be.
- ISL 12y agoIf you include the weight of the oxidizer, it's a wash. Oxygen, with mass 16, is pretty heavy compared with carbon's 12 and Hydrogen's 1 when you have to combine two oxygens with each carbon and one with each pair of hydrogens. The big win in "energy density" from normal hydrocarbons is that the oxygen is freely available from the atmosphere.