Our boat came with two new GPL-4DA Marine
batteries that have never really performed well at all. I suspect maybe they were "flat" from the get go. We have found doing anything simple, even just having the lights on drains them extremely fast. They just do not seem to hold a charge and drop really fast below 12v. In once case they fell to 10.3v overnight with almost nothing on. That morning we rushed to get shore power
and left them charging
with the built in charger
(also came with the boat) for nearly 24hrs. They seemed to recover only to their former lackluster self.
We now have a wind generator
going and do not let them go below 12v. However they have almost no ability to deliver power for more than a couple of hours under what I'd call very light loads.
These appear to be very expensive and good batteries (wired parallel for 12v bank). It's a lagoon
410s2 and there are also starter batteries wired into this system although I'm under the impression they are somehow separated from the house bank somehow. The boat (ex-charter) came with zero manuals
of any kind. When the batteries went low the first time we asked the seller who said they ran the engines 3hrs a day and suggested we do the same. Hence the Sunforce 600W wind
turbine was added. We do not want to become a diesel
power plant for 3+ hrs a day or we'd have looked into power boats from the get go
I read a while back about batteries something about dead is not always dead. They are either sufided up or just in need of conditioning charging
. Unfortunately for us our Sunforce MPPT
controller kicks off at 15v the voltage Lifeline says I need to maintain for 8hrs to condition them.
Before I spend more money
trying to condition charge these batteries can anyone help me understand what options I have? These seem fairly common batteries in a fairly common arrangement. Our friends who bought their ex charter
boat when we did have the same batteries. They have a solar
panel setup with a controller that will do the conditioning charge (fortunately for them as their batteries are outperforming ours but below their expectations).
Also, if anyone is considering the Sunforce 600W wind
turbine be advised that's only 600W with 24v battery
setup not 12v. It's advertised a bit misleadingly as 600w but they fail to mention you'll only see 400w if you have a 12v system.