Charging Different Battery Types

Question:

Jeff, thank you again for sharing your vast knowledge with us and answering the direct questions I’ve personally had for you.  You recommend Firefly Oasis batteries as house batteries yet suggest they’re the wrong type for starter batteries. Knowing the Victron battery isolator you’ve suggested does not manipulate voltage, how can I use one to charge the lead acid start battery with 14.4v and also get the charging profile I need for the Firefly from my 65A alternator? Can I install a DC to DC charger or some other voltage regulator between the isolator and the Firefly?  You highly recommend both of these products, so I have to assume you’ve found a way to run them together. I’ve seen a few people asking this question on YouTube, but can’t see the answer anywhere. - Scott

Answer:

DC to DC charging converters are meant to go between batteries. Unfortunately, I hae never seen a DC to DC charging converter installed between a battery isolator and a battery. For a custom charge profile from an alternator, you should install an external regulator to the alternator. - Jeff