That kind of plane could very much fly trans Atlantic with stop overs in Iceland or Greenland or further south from Kap Verde or Guinea to Brazil.
Well, you can’t take a battery powered flight anywhere, so yes, still a pipedream.
There are a number of battery electric planes, which are flying. Some are used to train pilots. So that part works. The issue is that battery energy density was too low, for them to become practical for passenger flights. That seems to change. There are number of smaller passenger battery planes in the work, for shorter fligths to islands and the like.
It’s more nuanced than that. Current battery energy density (250-300 Wh/kg) is ~15x less than jet fuel (~12,000 Wh/kg), making transcontinental flights impossible today. But shorter regional flights (200-400km) are becoming viable with existing tech, and several companies are already testing these. You can check out GearScouts.com to see how battery tech is advancing - the same LFP improvements are being applied to aviation.
Hopefully using this for transcontinent flight will be the one use. Since we should be able to build electric high speed rail everywhere that we travel over land.
