2003 Roadtrek hybrid battery system

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My trip through southern New Mexico has been very enlightening, power wise.

A hybrid battery system for a class C that doesn't move is very different from one for a class B that moves.

The class B doesn't need the AC lithium charger nor does it need the DC to DC charger to charge the LA. What it does need is a DC to DC charger (50 amp) to charge the lithium from the LA when the engine is running, a marine battery switch, and a three stage converter to charge the LA from shore power or generator. The lithium could also be charged at that time through the DC to DC charger.

I received a detailed explanation from Kisae explaining why the LA is being charged from the lithium whether or not the control input is at 12 volts. Bottom line is the unit is designed to work with a solar input in a marine environment. If the boat engine is started the battery input will cross a certain threshold, probably 13.2 volts, turn off solar charging, and charge the house battery from the alternator. When we hook a lithium battery to that port it is always above that threshold. The control input is there to override when input thresholds are not met but you still want to charge from the alternator.

The only alternative for us is to put a high current switch in the charging (lithium) battery circuit.

Anyhow, a hybrid system can be installed in a class B with the addition of a lithium battery and a marine battery switch if you want to charge it directly from the alternator.

As an addendum the hybrid system worked very well, having plenty of power in freezing temperatures. I did go through a lot of propane keeping the coach at 70F during the day and 55F at night. Both batteries were at 100% at sunset, daily.