I decided it might be too lazy just to buy a cool space stationy looking habitrail cage and suspend it from a balloon. So here's a Skystation Mk1 design based on a recent Hampture habitat I liked.I have more of the same peices and building one that doesn't need to be watertight will be even easier.
As you can see it will be using a rather heavy lead acid battery for power. This is necessary because custom lithium battery packs are a lot harder to make, safely charge and so on. If it's small (like a motorcycle stater battery) it shouldn't weigh too much. The weather balloon I have my eye on lifts 7 pounds. The completed station should weigh nearly that much so the upward pull doesn't strain the station or fishing line.
The solar fan cools during the day, counteracting the battery heated floor. Then at night (because it is solar powered) it shuts off, allowing the heated floor to do what it's there for. I am contemplating some kind of light sensor that will prevent the heated floor and LED lights from staying on during the day, to save power. Also possibly solar panels mounted on the ends of dual trusses, to charge the battery. But weight is an issue here, the battery is aleady a bit much, the solar panels might put it over the top.