all home built solar system

Author	Message
Solar Mike Guru Joined: 08/02/2015 Location: New Zealand Posts: 1204	Posted: 08:00am 23 Apr 2021         renewableMark said   Currently my system gets a 57.6v absorb charge for 2 hours each day then goes to float at 54v, would that charge profile suit lithium? Flooded LA. has to have a periodic higher voltage profile in order to stir up the electrolyte to prevent stratification; your 57.6 is going to be too high for long term Lifepo4 charge. 54v float is also little high unfortunately. I think he may have been talking about sealed LA, batteries, for a boat anyway, for this application. The video recommends max (12v system) of 14V or 56v (48v bank) which is ideal for Lifep04 at 3.5 V\cell, the difference in capacity to bring them up to max at 3.6v is only a few amp hours (400 Ah bank). I run my lithium's at 3.475 V\cell max during the balance phase and may only last 30 min, before dropping to approx 3.35 V\cell for float, at this setting bank capacity drops down approx 10 AH and sits there with zero charge current if there is no load on the system. When loads occur the PV charger supplies all of it if there is enough sun. Very interesting video though, and worth doing if you have sealed LA batteries. Cheers Mike