Originally Posted by Bruceea
I'm in the process of changing my coach batteries to Lithium. I have a new lithium 60 Amp Controller/Charger, along with 420 Watts of solar panels and 200 Amps of Battle Born Batteries. What do I do with the AGM battery that is used for the engine? I'm concerned about the charging profile for the Lithium batteries could damage the AGM battery.
What batteries did you have previously for the house side, flooded? A flooded battery typically gets charged to 14.2-14.6v, much the same with lithium. If you did not have a problem before then you should not now.
The alternator charging the lithium now that is a different story. You may need a DC to DC charger or a lithium BIM in order not to destroy your alternator.