Lithium Batteries

Make sure you use the correct converter/charger if you do a lithium swap.

I have been researching these batteries for awhile and still learning.

“You have to use almost all of the LiFePO4 batteries capacity before a lead acid charger will start charging again. A LiFePO4 specific charger will trigger bulk stage to start re-charging at typically 13.1-13.2V ensuring is starts charging again when it is still at high states of charge, not very low states of charge when it is going to be too late. Think about this when using solar to charge your batteries. When the sun comes up in the morning, a lead acid solar charge controller may not start charging at all regardless of the time of day if it thinks the battery is already charged based on the voltage it is reading as the re-bulk voltage hasn't been met. It will just stay in float stage. You may loose part or all of the days sunlight before getting any charge into the battery at all, leaving you with little to no charge and potentially flat batteries overnight.”

Winnebago has had them as an optional upgrade on their Views/Navions for a couple of years. Standard batteries are AGMs, or upgrade to lithium, for a few dollars more (~ $5000?). It became an option when the new flat top cab over was added. Same year.
Winnebago used the Zamp Solar Charge Controllers ZS-30A in my 2018 Navion. It came with a pair of cheap FLA batteries, but the solar CC has an LiFePO4 charging algorithm, which is almost the same as the AGM charging algorithm. I use it now, after swapping in a couple of Relion 100Ah RB100-LT lithium batteries back in 2019. Works just fine. I also have a Progressive Dynamics PD9245 converter/charger, to which I added a Charge Wizard remote control pendant. With it, I can manually boost the charging current to the lithiums when I'm plugged in, if they need it.

We have a 2019 Tiffin Wayfarer.
Lithium battery option was not available until the 2020 models.
We had ours installed in 2020 at the Tiffin Service Center.
Best money spent.