There a!re several threads on this topic. Lithium choices are many...so read up on AS experiences here.
We are currently looking at same. We have 6V Trojan T105's which we upgraded to 2 years ago. They work great, but we are looking at augmenting with a "portable" lithium pack like the Goal ZeroYeti 1000 or similar...have not pulled the trigger yet.
Going to full lithium package is $2-3K or so...and may need to get new converter that supports the Li batteries, so overall investment including solar, can get up there $$. That's why we are looking at the portable Yeti type solution to augment.
There is a good recent thread here:
https://www.airforums.com/forums/f44...es-205253.html
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Empty Nesters; Gypsies on the road!
2017 28' Twin Flying Cloud
2017 F250 King Ranch, 4X4, 6.7L, Blue-Ox WDH
Summer-Star Valley Ranch RV Resort (Thayne, WY); Winter-Sun City (Georgetown,TX)