If I were to order a trailer today and wanted lithiums batteries, what provisions are in place to allow the batteries to be changed in freezing temperatures? I understand the trailers are not four-season, but I'm wondering about temporary drops when camping in late Fall or early Spring, especially if I were to invest in the foam insulation and heaters on the tanks. Is the area under the dinette in the 21C kept above freezing when the furnace is running? How about on models where the batteries are mounted on the tongue or bumper? Do the batteries have an internal heat source? Heating pads under them?
Is there a DC to DC converter that allows the lithium batteries to be trickle charged from the tow vehicle’s batteries without frying the alternator? If not, can they be trickled charged from the solar panels while driving?
Hello Bryan, thanks for the questions about our lithium battery option. As you mentioned, our trailers are not four-season campers. The under dinette storage area of the 21C “should” stay above freezing if the furnace is running and would be OK for short periods of colder weather. I’ve sent your questions to our engineers, and they’ve sent back the manual from the battery manufacturer as well as the following notes.
In our attached manual, under storage, we recommend storing at room temperature. Storing below zero for extended periods, will negatively impact overall battery life expectancy.
Our guidance, is to remove and store when cold temperatures and inactivity are real (cold winter storage).
If using the trailer all winter long, below -20C, it is optimum to have the batteries all in the heated area. As you know when temperatures are -25 to -45C, these are hostile conditions, and hard on all equipment.
The heating circuit is designed to extend the trailering season, hence outdoor battery banks are doable with the heating circuit.
If you get caught out for a cold week, the heating circuit will pull you through, and not change the user experience.
The lithium option includes the DC to DC converter which boosts the alternator voltage to match the charging cycle required by the batteries during towing, also the solar system smart charger also is set up for lithium and is hardwired directly to batteries and is always providing charge to the battery system even under tow. (2 sources when towing)
Customers should consider the heating circuit consumes power so cannot be used indefinitely and should follow the data provided from the BMV 712 shunt and battery monitor.
I hope this helps, if you have further questions please post in this thread and I’ll try to get them answered.