For my longer rides, I found two pingbatteries a pretty practical solution. About 30 pounds, which is about the limit for my bikes panniers to carry without excess frame flexing. Close to 45 pounds total cargo, including the tools, water, a bite of food, etc. 50 if you carry chargers.
At a 20 mph traveling speed, 60 miles is for sure, but even slower riding could stretch it to closer to 80 miles. By then my butt is done anyway, after 4-5 hours in the saddle.
Even out here in the west, it's really rare to see more than about 60 miles between places a charge could be begged or bought.
Pings 5 amp charger will put 90% back into a 48v 15 ah in about 3 hours. So a long lunch somewhere easily puts you into 100mile range territory. Ride 25 mph for2.5 hours, charge 3 hours, ride some more. That would require a plug at about the 50 mile mark of course. If you butt is that leathery, I suppose a third session could be done.
Right away people are going to start howling about you could charge lipo faster. But in fact, two 5 amp chargers running at once is going to just about max out any plug on the side of a quick mart, that's also running an ice machine.
10 amps of 48v is not charging that slow.
Nothing wrong with going lipo, for the lighter weight and the smaller size. But you won't find plugs out there in the wild that are going to pull a 2000w charger. Chances are, 500w is going to be about your limit for a plug out on the road anyway.
