[deepspace]

Yes, when you start digging into the details, it turns out that they filled the plane, a de Havilland Beaver, to the gills with batteries. The batteries physically consume all the interior space, leaving no room for passengers, and they bring the takeoff weight to the max that the (electric) engine can manage.

With all that, the range is 15 minutes, with a 25 minute reserve. That is not even enough to reach Nanaimo, which is the closest town the planes could potentially serve.

So, neat demonstrator but a long, long way off from viable commercial operation.

[Robotbeat]

This isn't true. If you want to keep making these claims, you're going to have to provide a source. For instance, there's plenty of space behind the pilot that is empty. There's plenty of interior space as the batteries are placed below.

Additionally, they are using bulletproof flight-certified batteries which are much lower than the typical good lithium ion batteries used in, say, a Tesla. They're just for the prototype. "“These are batteries that NASA is using, but they’re not batteries that we’d use if we were going to try and make it economical to fly today, because they’re very low in watt-hours per kilogram,” explained McDougall."

The electric motor (not an engine) is 560kW, almost twice the original 336kW radial motor, so it's not in the least underpowered (as you imply).