Originally Posted by Shocksll
Nice, this has been my first winter with my two heated 100Ah Battleborn batteries. Since the heating is done internal to the battery, my BMV is unable to detect this usage. Today i noticed that the battery heater must be getting turned on because the BMV was showing 100% but my solar
was still dumping 7A of charge into them.
That is an interesting problem. The lithium battery monitors typically count amps in and amps out to determine the percentage of charge, while the charger looks for a voltage rise to determine full charge. So if the monitor doesn't see the internal heating load, it has no way of factoring that into the percentage of charge.
How will you resolve this? Maybe you'll have to wait until the battery is fully charged, based on the charge current going to zero, and then reset the monitor to 100%. But in cold weather you'll never know exactly what the state of charge is.
I don't like the idea of the battery using its charge to heat itself. What a waste. But with outside batteries, that seems to be required. So, lithium batteries on the trailer tongue, or in exposed pull out trays, like the Oliver
has, will have this disadvantage. Installing batteries inside the trailer is the solution for winter camping. As the industry moves more toward lithium, putting the batteries inside will have to be considered and should be looked for when purchasing a trailer.
My X22, for instance, has them centered in the trailer, under the bed. In winter, battery usage is high and the sun is weak, so wasting energy to electrically heat the batteries could be a problem. And a false monitor percentage will hide that problem.