I will add that the lithium batteries are great in cold weather. Why? We previously had 140 A-hr of lead-acid batteries and we generally couldn’t get through more than a couple of cold nights without the gas heater quitting. The lead-acid voltage decreases rather rapidly with discharge and by the time they were discharged only perhaps 30% the voltage was low enough that the blower in the gas heater would not spin fast enough to activate the airflow interlock switch. The Lithium batteries are higher voltage to start with and have nearly flat voltage characteristics until down to about 10% charge. Now we can run the heater (and everything else in the camper) for many days on end, even when solar charging is not possible. We will run out of gas before we will run out of power. It won’t take you many nights of 10 degree temperatures and having the heat fail for you to appreciate this.