So I'll admit when i'm wrong, I thought Winnebago would be years away from anything like this. However they are going full speed ahead with a 48V Lithium NMC battery pack (close to 833ah if you are talking 12V), 3600W inverter, 58V second alternator and DC step down converter for 12v appliances. The option to go with NMC vs lifepo4 is obvious since they aren't bothering to stick with 12V. The problem with other lithium chemistry has always been the nominal voltage. lifepo4 has a nominal voltage of 3.2v so 4 in series makes a really good 12V battery. most other lithium has 3.7v nominal so 3 in series would be too low and 4 in series would be too high. However if they are going to skip 12V all together and go with 48V, other lithium chemistry will give you much better performance and weight savings.
NMC power density is WAY better than lifepo4. For comparison, lead acid has about 40WH per KG. Lifepo4 is around 120WH per KG. NMC is around 230WH per KG. Cycle life on NMC isn't as good as lifepo4 though, however you can still expect 1000-2000 cycles. I'm still skeptical about the safety of NMC, but this isn't a DIY pack. I'm sure they are a lot of safety measures and they aren't charging the cells to their limit (4.2 volts per cell is the max and they are only going to 4.15).
The alternator is the real winner with this setup. Having a higher voltage alternator means it can provide a much faster charge. They can easily push 100amps through that alternator then you've got close to full charge in a little over an hour.
The obvious application for this is running the air conditioner then have the ability to quickly recharge the battery from the alternator. A battery this big, second alternator, inverter and dc-dc converter is going to be $$$$. My guess is this is going to be north of $25k upgrade on top of the $75k price of the travato.