They made a new type of thermocouple?................
That was one of the questions in the video. At about 49 minutes in.
Biberian said there’s no contact potential, because there is an intermediary between the two. There is no contact, they are separated. In the vaccuum there is no voltage. You need the hydrogen to get it to work. Contact potentials caused by Voltmeters are in the milliVolts, this effect was 500X bigger than that.