IIRC there's been quite a few of these scams.
A few years back there was a water bottle that filled itself through the same claims. Turns out it also was a scam. Pretty sure it had backers on gofundme or kickstarter of several millions. Oh, Fontas, the Self-Filling Water Bottle.
Then there's that wristband (Cicret Bracelet) that projects a screen on your arm, and registered your touch - turning your arm into a touchscreen computer. Turns out pico-projectors don't exist to fit on the wrist, and even if they did you'd only be able to use in in the dark despite them saying a projector could be seen on your arm in direct sunlight.
Next thing we'll see is a gas cap that converts the air into diesel fuel.