I have 2 solar arrays (with separate MPPT). I have flooded lead acid start and house batteries. I receive more solar power than I can store, I want to capture what I’m missing and put it in to a lithium battery, efficiently. What is the best approach? Thank you.
Guessing this is a mobile application and there's more equipment than you mention.
Better if you give us more details of loads, other kit. And how you intend to use the existing and new batteries. Lithium and AGM are better kept apart, with Orions as a bridge.
It is a mobile application (sailboat). At the moment it’s 670W solar through a SmartSolar 150/45 and 360W through a SmartSolar 100/30, connected to 460AH FLA. I was thinking of adding 200AH lithium and either using a DC-DC 30amp from the lead, and then moving some loads (a freezer etc.) to that battery alone, or instead moving both solar controllers to the 200AH lithium, and then DC-DC charge the lead acid bank. I worry that if I go with route one, that the lithium bank will take the majority of the incoming solar power at the beginning of the day and not give priority charge to the lead. I’m really after catching the power I’m not getting from the point the lead acid is nearing the middle of absorption.
both might work but depending on the age of the lead acids it might make sense to replace them with another lithium battery. Better redundancy, less complexity, less devices, less headache. Just my 2 cents
