After five years of lurking, Turing fuel cell discussion finally made me register and post on TMO.

No perpetual motion here, actually. A chunk of something that reduces water, and needs to be replaced after depleted: "... contains a replaceable solidified chemical fuel...", as they say.

I believe most of the fuel cell prototypes for electronic devices so far have used ethanol or methanol with external oxygen, and water being exhausted, but nothing that much wrong with using solid fuel and otherwise closed system? (Thermodynamics and Hess's law actually tell us it's thermodynamically ok to convert 2 H₂O <-> 2 H₂ + O₂ back and forth if we really want to)

"what would they be like if you transported a hydrogen filled fuel cell?" Hydrogen without oxygen is pretty inert, and not THAT dangerous in such small amounts anyhow. And some/most of it will be bonded as water all the time - maybe it will actually extinguish itself in case of fire? Anyhow, I find lithium batteries scarier.

Theoretically everything's pretty ok. Of course, such devices being delivered in the near future by TRI, that is a completely different question...