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> This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft

• chx 3y ago
  I am sorry but either math or English comprehension fails me. 12 000 Wh/kg vs 400 Wh/kg is 30 times better.
  • luckystarr 3y ago
    Regarding gasoline: the question is how much of that energy is actually converted into motion instead of heat. With electric mirrors it's more than 90%, with gasoline it's more like 30-40%.
    • anticensor 3y ago
      I am sure you meant motours/motors, not mirrors.
      • luckystarr 3y ago
        Yes. Gboard is getting ever more useless.
        • loa_in_ 3y ago
          And it never fails to capitalize brand names and suggest them over normal words...
          • hinkley 3y ago
            If I talk about the malus genus it always tries to turn it into Apple. Just like that.
        • pomian 3y ago
          And what is with the numerical replacement of a word? Just before pressing send, if you're lucky, you catch something like, an engine may be defined by it's 6 in cubic inches. (Instead of displacement.)
      • hinkley 3y ago
        I’m about to turn off autocorrect. It’s < handling of apostrophes makes me sound like an idiot, and it’s (that’s two) auto replacement of words makes me sound like I’ve had a stroke. A couple times I have checked a response I’m (three strikes) the morning and it is so garbled I can’t remember what I was trying to say. It used to work better, right? I’m not imagining it?
        • marak830 3y ago
          Yes, I believe it did used to be better, I feel like I'm fighting the damn thing now.
    • olejorgenb 3y ago
      10-13x better then
      • Gibbon1 3y ago
        Basically if you figure a EB battery weighs 1000 lbs and 10 gallons of gas plus the tank weighs 75lbs. Gets a lot better when you include the weight of a gasoline engine plus transmission vs an inverter and electric motor. The difference there is a few hundred lbs. Take away is even what seems like small improvements in power density saves a lot of weight. Increase the density by 10% and you shave 90lbs off the battery and reduce the cars weight by 4%. Your gain is more than the reduction of the weight of the battery because cascading reductions in the weight of the cars structural elements.
        • drtgh 3y ago
          The torque required for an electric vehicle to climb a slope quickly drains the battery (if the electric motor can climb it, and if the refrigeration can manage the temperature rise along the climbing time [hill, road, etc; constant torque]). Combustion engines have a high torque, and these variables should be included in the equation. IMHO, it should be mandatory to include in the electric vehicle specification the range with a 14-20% of slope/gradient[1], including the speed. [1] although it does exist some ways with 30% of slope, some wicked garages included.
  • pcl 3y ago
    Indeed. Clearly I shouldn’t do math in the morning! It seemed like an impossibly good number.
• Forbo 3y ago
  ...isn't that 30x? Also, I saw it listed as 500Wh/kg from the article, where was the 400 figure coming from? At 500Wh/kg, it's about 24x the energy density. Also the NASA paper was published a year ago, and the article linked in OP was published a few months ago. Is there some development that is causing this to surface again now?
  • pcl 3y ago
    I saw the 400 number in the abstract of the paper. And yes, terrible math on my part!