Hi Reed,
LI is one of the possible futures. Currently the lowly Pb flooded is still the best bang for the buck. I have four that are four years old (one used as the starter battery in my class c) and four that are eight years old. It gives me about 400 amp-hours to play with or about 5000 watts.
The real problem is how do we recharge? When I was a weekend warrior I could, with extreme care, boon dock for 13 nights, with an outdoor temperature of 2 c (35 f) and maintain the rv at 20 c (68 f). I would run out of propane before I ran out of power.
On a 3 day trip I could afford to be extravagant in my usage. Now that I'm full time--I hope to bump my system up to over 1000 watts of solar. Parts will be around 1700.00. I may end up with about 1250 watts for my solar farm.
If I do this, I'll end up being able to run the air conditioner during the hottest part of the day more or less directly from the solar panels.
I'm sure someone will say--but what if there is no sun? Well, if there is no sun--I won't need the air conditioner now will I?
How to justify the cost? Well the Yamaha 3000 iSEB uses .45 gallons per hour at full load--so it will run just under 8 hours. (3.4 gallons)
3.4 x 3.25 =~ 11.00 per day plus the cost of an oil change once every six days.
1700/11 =~ 155 days--and I'm home free.
