There is quite a cost to this with the Gen4 having a smart alternator, so I have been thinking of alternatives. I thougth it would be best to improve the exsisting battery rather than put work into one more problem to maintain. at least when there is no winch yet. With the Noco, I was just thinking to power some USB LED strings lights and to use as a power bank type thing and hopefully have enough left for a jump-start. I just enlarged the original battery stand and squeezed a 70 Ah AGM battery in there. No more problems in cold weather, never worry when the lights are left on. and just a large USB battery bank for stuff that needs charging on travels. Any thoughts on these options or any I have missed? I would welcome comments from seasoned campers.

Bison Smart Battery Box with 4 extra USB outputs BISON

After I have been making very good experiences with a LiFePo4 for my motorbike I wanted to test this as a car battery.I installed an 45Ah LiFePo4 battery as primary battery and moved the original battery into a second tray. Probably have the same power as a secondary battery, but only need to take it when out on an adventure, not all the time Don't know much about smart alternators but plenty of caravan owners must already be charging the "second battery", if you camp this would make sense. some of those can do jump starts as well, but i do not need that anymore i think. Still bring starter cables just in case. Suppliers/Dealers or anyone selling with a commercial view in mind CANNOT post here unless responding to a specific request of a member in a "wanted" post.

Minn Kota Trolling Motor Power Center - Black/Red Minn Kota Trolling Motor Power Center - Black/Red

In the Gen 4 I think room could be made by relocating the washer bottle over to the bulkhead and putting the 2nd battery in its place.Where you have relocated the washer bottle is like what I was thinking for the Gen4 although it looks bigger 4 liters I think it is? Like you say a battery box would require some memory to remember to charge it or keep it connected to a battery conditioner. But you are only carrying when needed.

Bison V2 Deluxe Battery Box Carrier with 5 X USB Chargers

A secondary battery i think is the best option so far. My dash cam would recored for days on end in parking mode. No need for a Noco or similar so that would offset the 2nd battery cost.