> Even with the highest theoretical possibilities, batteries cannot be as energy dense as kerosene. So what? We can make kerosene-fueled aircraft that can fly

> Even with the highest theoretical possibilities, batteries cannot be as energy dense as kerosene. So what? We can make kerosene-fueled aircraft that can fly more than all the way around the world without refueling. In fact, we did it 15 years ago, and we left some performance on the table as it had a L/D of 37 but modern sailplanes can get over 70 L/D (and the jet engine they used wasn't particularly efficient), and with forced laminar flow control, 100 L/D is possible. https://en.wikipedia.org/wiki/Virgin_Atlantic_GlobalFlyer https://en.wikipedia.org/wiki/Virgin_Atlantic_GlobalFlyer Kerosene is better than it needs to be. Cutting edge typical lithium ion chemistries (like you might find in a Tesla) has about 300Wh/kg, but pre-production lithium-sulfur batteries can get up to 650Wh/kg (lithium sulfur and lithium metal anode batteries that are available in sample quantites in actual pouch form are around 400-450Wh/kg). But also, batteries are roughly twice (sometimes 3 times) as efficient as jet engines. As you mention, chemical batteries could do 1100Wh/kg (not counting lithium-air, which could do much, much better but we're probably a couple decades to deploying them). Not getting lighter over time is a performance drag, but there are actually ways to deal with it. But let's split the difference and say batteries could be about a tenth as good as kerosene. 41,000km is the distance that Globalflyer flew. A tenth that range is 4100km, which is the minimum flight length to qualify for long-haul (and also the distance from Hawaii to California). So we could have long haul electric flight if we wanted to, without the solar-electric trick or any kind of towing, in-air charging, staging, or launch-assist. Turnaround in 30 minutes isn't fantastically hard for battery chemistries, either, BTW. 5 minutes would be pretty hard, although still not impossible (and some chemistries can do this). And again, this is largely scale-invariant. A Tesla that can mostly charge in 30 minutes means a short-haul aircraft could as well. And you can get lithium batteries (LiPo and Lithium Titanate) that charge in 6-12 minutes or so (5-10C rate). This is faster than most jets get refueled (it takes 45 minutes to an hour for larger jets, so I don't see charging time to be a huge challenge).