Should I go Lithium?
Ask any group of avid RVers about what kind of battery to buy and several will say, "Get lithium batteries." Though their hearts may be in the right place, it is not their money and most don't understand lithium battery technology, its strength, weaknesses and pitfalls.
Lithium batteries are a relatively new and still maturing technology. In addition to being more costly, some have major flaws that can see you wasting big dollars in a big hurry if you buy the wrong ones.
There are several lithium battery technologies and types. The type currently best suited for use as house batteries in an RV is Lithium Iron Phosphate or LiFeP04 batteries. It should also be noted that most "drop-in replacement" batteries are not as simple as dropping them in and away you go — at least not with what is available today. Other components, such as your charging system will require adjustment and, in certain applications, you may even wish to change where your batteries are installed.
The better brands of LiFeP04 batteries will have thermal protection but several budget brands do not and this can result in severe problems. Research and learn about Lithium-Ion batteries before putting down your dollars and carefully follow the battery manufacturer's instructions on installation, charging and general use.