At the very least, it seems like there might be some prospect of combining the battery and voltage upticking tech here with the likes of the solar-powered Zephy

At the very least, it seems like there might be some prospect of combining the battery and voltage upticking tech here with the likes of the solar-powered Zephyr [1] which can fly at about 20km, which is apparently about the denser part of the ozone layer [2] [1] https://en.wikipedia.org/wiki/Qinetiq_Zephyr https://en.wikipedia.org/wiki/Qinetiq_Zephyr [2] https://en.wikipedia.org/wiki/Ozone_layer https://en.wikipedia.org/wiki/Ozone_layer , in particular: https://upload.wikimedia.org/wikipedia/commons/thumb/c/cb/Ozone_altitude_UV_graph.svg/300px-Ozone_altitude_UV_graph.svg.png https://upload.wikimedia.org/wikipedia/commons/thumb/c/cb/Oz... - ed I suppose it would make more sense to pair the battery and voltage conversion tech with a high altitude balloon covered in thin film PV, so there's less competition between 'ozone generation' and the 'lift generation'.