Deep Cycle Battery Charging From Alternator
Hello, May I ask for advice regarding charging deep cycle batteries from the alternator? I have read older threads, and understand opinions vary. The previous two 100Ah deep cycle AGM coach bat...
Forum Discussion
time2roll wrote:
I would charge your AGM after a trip with your 3-stage converter 24 hours then disconnect the battery for the daily driving. Reconnect when packing for the next trip. I recommend Lifeline brand battery and Progressive Dynamics converter.
Problem there is you can't meet the Lifeline charging specs with a PD converter. You can pick the right amps size to meet the 20% charging rate, but need adjustable voltage to meet the spec voltages and then adjust those voltages for temperature compensation.
The PD 14.4 or 14.8 fixed voltage will nearly always be wrong, and never right for the recommended "conditioning" charge of 15.5 as adjusted (could be 16v eg) when the battery is used for deep cycling.
IMO, when you can't meet the charging specs for AGMs (also need an ammeter to see when you are at the 0.5a/100AH point) you are way better off with a Flooded , not sealed, battery. You can tell where you are at with an hydrometer and can add water as needed.
Only trouble is where you can't get at the battery to do the work without taking the whole RV apart or hauling 70 pound batteries out from trays so you can see down the cells. AGMs are desired for that, but now you are back in the soup for how to look after them without an adjustable voltage charger and an ammeter.
http://lifelinebatteries.com/wp-content/uploads/2015/12/6-0101-Rev-E-Lifeline-Technical-Manual.pdf
