Solar charge settings for lithium

[sailorboy1]

Beside my general "feelings" of what might be good solar charge settings for 12V LFP, what are other using cruisers using based on their experience? I found some numbers on the Battleborn site and they seem "aggressive" to me really to use all the time.

My main question is what absorption voltage to set to and for how long to hold it. My feeling is to do 14.2V and only hold for 5 minutes then drop to 13.4V float. Maybe once a month go to 14.4-14.6 to balance.

[sailorboy1]

no one I guess

[ThereAndBack]

FWIW, I have battleborn batteries. I bought my inverter/charger and solar charge controllers from them, they came preprogrammed with battleborn's settings. I've had my batteries for 4 years now and no problems.

If your manufacturer doesn't provide charging guidance, I would look for one that does that matches the cell type your battery is using. For instance, if you've got prismatic cells, I'd look for another that uses those. Battleborn uses a different cell than a lot of the drop-ins now a days.

Some other points. You should never do an overcharge or balance charge on LFP batteries. They're not like lead batteries and if you charge them to 14.6v you will damage them. Don't do it!

LFP batteries don't need to be fully charged. They're not like lead batteries. They're not damaged by not reaching 100% SOC on a regular basis, so don't sweat that, you can be conservative.

LFP batteries technically don't need absorption or float charging. Set those to the shortest durations you can and set them both to something like 13.4v.

Go conservative and see how it goes and adjust upwards cautiously. A few percent below full is safe and like I said, LFP doesn't need to hit 100%. Don't set an equalization at all! If your charger requires an equalization charge, set the current below 14v.