A demo at All Things D 2 years ago: http://allthingsd.com/20110602/demo-at-d9-ubeam/ http://allthingsd.com/20110602/demo-at-d9-ubeam/ The design in that video

A demo at All Things D 2 years ago: http://allthingsd.com/20110602/demo-at-d9-ubeam/ http://allthingsd.com/20110602/demo-at-d9-ubeam/ The design in that video involves transmitting ultrasound from a central charging station to an ultrasound receiver and that receiver is then plugged into a cell phone using a normal cable. The claim in that video is that it takes 3.3 hours to charge the receiver but she doesn't actually mention the watts or joules involved. Given that most claims of technology that can charge a device from across the room have turned out to be bullshit, I'm going to lump this claim of into the same bucket until there is more evidence to show otherwise.