EV range extender

On the surface, this seems trivial. A guy wanted to be able to buy a Tesla range extender, which Tesla teased at some point, but never delivered. 

[an EV has a battery pack that holds a charge, and allows for a "range" (ie, some number of miles that can be driven) based on the general characteristics of the car, climate conditions, speed of travel, etc. Like a gas powered engine, which needs to refuel when your tank is empty, an

EV needs to recharge when that battery is exhausted. A range extender would allow for you to go longer distances. It's like an extra battery pack - or in gas parlance, an extra fuel tank]

Since he still wanted one, he built it himself for $11,000, and can travel an additional 100 miles by using it. It's not integrated, so he has to stop and plug it in to his car. 

As many pointed out, it's more efficient to simply go to a supercharger than to plug in this device. 

But that's not really the point. This is about innovation and learning. He sees how (theoretically) it could be integrated. He also sees that he's had no change in the range he was getting, even though this device is fairly heavy and always in his car. 

And he's stirred some creative thinking on the part of others. So there's potential for future growth of innovation. 

Tesla Wouldn't Sell Me a Range Extender For Cybertruck, So I Built My Own, Giving Me Just Short of 100 Miles of Extra Range | Torque News https://www.torquenews.com/1/tesla-wouldnt-sell-me-range-extender-cybertruck-so-i-built-my-own-giving-me-just-short-100-miles