Her quick Google to see if someone had done anything like she is proposing should have trawled up a lot of hits. We don't see too many of those in production use today. I wonder why? :-)
Yep, I found all those links to research and articles on my first page of Google results, I think most of them pre-date this project by a long way.
To be fair, she does address the focussing issue that Dave implied she skipped over. The video does say the charger and chargee need to be paired, and the acoustic beam needs to constantly steered, with the chargee constantly feeding back to the charger to control that steering. No indication is given of how a suitably tight beam might be formed, though.
And therein lies the rub. As usual with projects like this there is no real proper engineering demo (after what 4 years and a million or two invested?). Just seems to be the odd mention from some tech writers or journalists who claim to have seen some sort of demo. Most likely those people would be fooled by the "5V output" nonsense too.
If I had this thing even remotely feasible I'd be making a dozen videos screaming to the world and investors - "Look, see, it really does work, it really is promising, look at the efficiency and tracking we are getting etc etc.
But no, after 4 years all we seem to get is a photo in the New York Times of, well, something?
Meah