Your argument seems to be that some bits of tree doesn't constitute what we would usually call a "device", and that's fair enough really. I called that out myself in the same comment, so I guess you picked up what I was laying down!

The "wood is a solid-state battery" thing was an absurd rhetorical device I used to point out -- particularly in a field so significantly connected to electronics -- that merely substituting a liquid for a solid does not justify using what will obviously be understood to be a reference to solid-state electronics.

P.S. A coal-fired steam engine is a solid-state motor.