Bipenut53
150cc
The first consumer electric airplane...? With some tweaks to the power system and ever expanding battery capabilities, I don't think it'd be a problem to get 2-3 hours out of that airplane in the air.
Just a couple years ago I remember buying a 3s 1000 30c lipo pack and thinking how little it has changed since the days of the Thunder Power 1300mah 16c packs. Then I bought some new TP 3s 900mah 55C packs recently and they were half the size and almost half the weight. The point being, battery technology is moving quickly.
Battery technology has always been the problem with anything powered by batteries. I know that Elon Musk has invested millions in trying to improve the batteries for his cars, we will benefit in the end by his and others research. Think about where batteries were for our planes even just 7 years ago, much better now. The graffine and carbon based batteries are showing some promise but they are still searching for better solutions... I am always impressed we can do what we do with just the now simple lipo setups we have. It will be interesting to see where it goes from here in the next 5 years....