Solar Scooters introduced its Hyperion electric scooter that can top out at 65 mph and has a maximum range of 70 miles.

  • MentalEdge
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    13 days ago

    Wattage is amps times voltage.

    Voltage determines motor RPMs, amperage determines torque. (Simplified)

    50V at 60A is 3000 watts, but so is 25V at 120A.

    But the system configured to run at 50V can achieve twice the speed of the one at 25V. The 25V system is also 3000W, but all it can do with that is achieve its top speed really fast.

    It’s a bit more complex than that. At lower speed the higher cmvotage system can function like the lower voltage one, as at low RPM and therefore low motor voltage the ESC can pump up the amps while remaining within the power limit of the battery (up to the amperage limit of the motor), but once the ESC is pushing the voltage coming out of the battery right into the motor, there is no going faster even with watts to spare. Maintaining speed doesn’t take as much energy as accelerating, so as you hit top speed, power consumption actually goes down.

    Unless you sacrifice the amps/torque/acceleration to gain voltage/top speed, more power doesn’t mean a faster PEV.

    • sploosh@lemmy.world
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      13 days ago

      I imagine one would have a motor controller that included something along the lines of a variable frequency drive (VFD) and a boost converter for something in the 4.5KW range, which would largely mitigate the issue and open up the door to using a small forklift battery as the foundation of a motorcycle.

      • MentalEdge
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        12 days ago

        I’m not aware of any BLDC ESCs that implement boost conversion.

        Looking it up it seems such a circuit would be beefy indeed when built to handle the amperages of propulsion.

        Controlling the voltage coming out of the battery is already done using pulse width modulation, but this can only reduce the voltage, not increase it.

        There’s little point in boosting the voltage to achieve higher top speed, as configuring a battery pack for voltage is very easy.

        To the point that I’m here lamenting that PEV designs are upping the top speed even when utterly unnecessary.

        • sploosh@lemmy.world
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          12 days ago

          I was joking, yout silly potato. The forklift battery thing was supposed to be a tipoff.

          • MentalEdge
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            12 days ago

            Why would there be anything wrong with a forklift battery?

            A battery pack is a battery pack.

            Drop an /s next time.

            • sploosh@lemmy.world
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              12 days ago

              Forklift batteries are also ballast. They’re lead-acid and weight 600lbs at the minimum. It’s a comically bad idea to use one for a personal vehicle.

              • MentalEdge
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                12 days ago

                Thanks. I’ll go ahead and file that under “obvious common knowledge” going forward. /S

                I know how lithium packs work and how to program a VESC. That’s all.