Hi Jeff. I am upgrading to lithium and hi output alternator. One thought is to connect a high output alternator to a Victron Argofet 200 amp three output isolator to charge lithium bank and two AGM starter and bow thruster batteries. My other thoughts are to connect the alternator directly to the house bank then adding a Victron DC to DC charger from the house bank programmed for an AGM charging profile then connecting to the isolator to charge the starter battery and bow thruster battery. Will both work or neither? Thanks, Clay
Thanks for reaching out.
Your second suggestion of the DC-DC charger is close. The recommended alternator connection in this situation is to have the alternator and regulator connected to the AGM starter battery first - then install your DC-DC charger(s) from the starter battery to the lithium.
This lets you regulate the voltage going to your lithium house battery bank and ensure that in the event of a lithium BMS failure the alt still has a place to dump its charge. This way you won’t potentially end up with a dead house bank and no alternator.