Just disconnecting the ignition might not be enough. Driving down the road, if the generator is started, the alternator will still connect to the Li batteries and potentially stay connected after the generator is turned off.
If the BIM-225 has a ground connection, disconnect or put a switch on it. Less chance of a short later.
And, with this mod, the house no longer charges the chassis battery.
__________________________________________________
Cliff
2011 Four Winds Chateau 23U