I don't need 750hp
Hope they make a 5lb one with 100HP  

A Tiny 29-Pound Electric Motor Just Beat Everyone in Power Density
https://www.popularmechanics.com/cars/hybrid-electric/a65490281/tiny-electric...

Yasa, a small British engineering company, built an over-730-horsepower beast that weighs just under 30 pounds.

 I've seen some DARPA prototypes that rip out some incredible torque, but the issue is the weight of the power source.

 Batteries still weigh more than fuel believe it or not.  


 I'm going to put this out here and take it down if requested:

 I bought an electric mower to see how it performed.  I typically burn as a way to kill weeds and remain sane - but mowing is also part of the deal.  I was offered the chance to retrofit my mower with a prototype electric drive as long as I collected data.  It produced more power to weight than a gas engine of near-identical mass.

 Given the civilian market for electric mowers I would not have believed this was a current outcome, but I can't argue with the numbers.  Electric engines have a potential the consumer market has not seen - yet, but given we can actually build a non-reactive infrastructure I too believe it will replace the combustion engine for most functions.

It's the power source that concerns me. The way the planet is getting stripped of lithium and other minerals seems pretty destructive.


 I think it's because we are more aware of it due to modern technology - AKA the internet.

 During the industrial revolution had we the knowledge of fossil fuel extraction impacts, maybe we would be thinking the same thing then:  "I'm all for that newfangled combustion engine, but I sure am concerned about the availability of fossil power."  

 Maybe.

Eegore wrote on Yesterday at 19:02:13:


To make a reasonable comparison, one would have to:
 - Add the mass of the fuel tank and enough fuel to give the desired power output and run time to the mass of the internal combustion engine.
 - Add the mass of the batteries, battery management system, and any required onboard charging components to the mass of the electric motor, again, providing for the desired power output and run time.
 - It's not really fair to make calculations based on the incredibly high torque that is available from an electric motor at zero rpm.  We should be comparing USABLE power outputs, at normal blade speeds.
 - From your description, I'd assume that the vehicle itself was liquid fuel powered, and only the mower function was electric powered?  How does the picture look when everything on the vehicle is electric powered?

Considering that the best average power density of current Lithium ion battery technology is something like 300 Wh/kg, (watt-hour per kilogram) and gasoline offers something like 12,000 Wh/kg, I'm pretty skeptical of your claim that any electrical application offers a better power to weight ratio when the full picture is being considered.  Please share the details.