[acyou]

I tried a few back of the envelope calculations, with a 21700 cell with the same characteristics as a Boeing 737. Looks like you don't need that much power to stay aloft when you're small. If you're buoyant, even less. I guess small insects take great advantage of this.

If potential energy can be stored as height, why do you need batteries at all, or why would better batteries help? Can you get a low enough descent rate to glide all night and climb all day?

How much power is realistically required for night-time station-keeping?

I would have thought that large birds would be around the right size, shape, weight and flexibility for dealing with flight problems. Why would bigger be better in a highly scale-independent propulsion system ? Is it just the back of the envelope size needed for enough solar gain? Why is 110 ft needed? As others say, 110 ft sounds much too big to live through turbulence...