What Are the Implications of Recharging the Battery With an Alternator Only?

Question:

We are very pleased with the Firefly Oasis AGM battery you installed for us. We can actually relax about our power consumption now. We should have made the changes much sooner! Regarding charging the AGM battery, is it harmful for the battery to be charged to inconsistent levels by the alternator? When on the boat for several days, the battery does not always get fully recharged each day. Is it better, when possible, to minimize alternator charging and maximize charging with the smart charger when connected to shore power? - Sean

Answer:

I appreciate the follow-up and glad to know you are enjoying the new Firefly battery.  This is exactly where Firefly Oasis shines as it can handle NOT being charged to 100% without suffering from the effects of sulphation. You’ll certainly get a better charge if connected to a smart charger, since it will re-charge the batteries to an AGM profile.  - Jeff