Comment on New breakthrough may let us charge smartphones in 60 seconds

• brie@beehaw.org ⁨6⁩ ⁨months⁩ ago

  Increasing capacitance (how much charge is stored to reach a certain voltage) or the voltage it is charged to would indeed increase the capacity. Putting several in parallel would work, as would making a bigger capacitor. The main problem as far as I can tell is that the energy density of even supercapacitors is low, so you’d need a much larger volume to have the same capacity (and thus a much thicker phone).

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  • cygnus@lemmy.ca ⁨6⁩ ⁨months⁩ ago

    Thanks for this - I was doing some reading in the meantime which confirms what you’re saying about power capacity.

    en.wikipedia.org/wiki/Capacitor_electric_vehicle

    As of 2010, the best ultracapacitors can only store about 5% of the energy that lithium-ion rechargeable batteries can, limiting them to a couple of miles per charge.

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    • Thevenin@beehaw.org ⁨6⁩ ⁨months⁩ ago

      Yeah, this matches my experience.

      A supercapacitor buffer will cost around twice as much and deliver around 1/10th the watt-hours of a similarly-sized lead acid battery. And lead acid isn’t exactly great to begin with.

      Capacitors are useful, but only in applications where the total amount of energy stored is more-or-less unimportant.

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