Dead AGM's, need help,

[Mr B]

Coming from Fiji to OZ,
I had 360 watts of solar panels on board. 2 x 100 watts and 2 x 80 watts,
I had a 913 Rutland wind generator,
Two X 200 amphr lead acid batterys, 400 amphrs total,
I never ran out of power running every thing 24/7.

I now have 500 watts of Solar panels, 2 x 250 watts each,

600 amphrs of AGM batterys and 2 x 160 amp lead acid start batterys, ,
I bought the lead acid batterys as my AGM's died overnight, While moored,
I had motored for over 24 hours running on the alternator on the diesel the day before,

And a wind generator from china, I basically havent used it yet as there has been no wind, It was cheaper than a new controller from Rutland which I accidentally drowned,

Even with every thing turned off, The batterys still drain overnight,
My alternator is new and I believe it pumps out 50 amps,

The only thing different is the AGM's instead of lead acid batterys,
I run a freezer full time, which draws 2 amps,
In the marina I kept it on 240 volts thru an AGM charger that turns off when the batterys are full, 12.4 volts,

Sailing, Its on the solar panels and the diesels alternator, Which both do charge the batterys,
But they still discharge over night, Like some thing is on and pulling lots of amps out of the batterys,

I checked the solar panels, They have 2.3 on all the connections between the diodes,
A really big wave crashed down on them, But inside the box its bone dry and never had water in there,
But have an error on the leads out from the panels and from the panels to the diodes, On the multimeter,
But the panels still charge the batterys, ???????
The diesel still charges the batterys,

All the AGM batterys are new, 200 Amphrs, 2 x 6 months, One 12 months,
The two lead acid are about 9 months old, Max. 160 Amphrs each,

Solar is thru a Controller with a circuit breaker for a fuse, next to the batterys,
The batterys are currently 11.7 amps. So basically dead,

Does the Diesel alternator kill AGM batterys,
Will the wind generator and controller kill AGM batterys,
Will the Lead Acid and AGM's tied together kill each other,

All my batterys are in the one bank and 12 volt,

Would I be better buying new lead acid batterys or getting more AGMs.
I bought the AGM's for convenience as they dont need to be maintained, Water added weekly,

Keep it simple, Please, as I dont understand electrics,

All help appreciated,

Thanks, Brian,

[Wotname]

OK, I will keep it simple.

1. Never mix new and old batteries together.
2. Never mix AGMs and 'lead acid batteries'. BTW, the better terminology is Flooded Lead Acid (FLA) instead 'lead acid battery'
3. AGMs must be fully charged as often as possible - like every other day. And fully charged means 100%, not 95% or 98%.

[Wotname]

In case it wasn't clear, doing ANY of the above three actions will kill batteries quickly.

AGM and FLA have different charging profiles.

[SaylorMade]

A full charge is not 12.4 volt.
If the charger stops charging the AGM's at 12.4 that is a big problem I think.

[Wotname]

A full charge is not 12.4 volt.
If the charger stops charging the AGM's at 12.4 that is a big problem I think.

Good point, I totally missed that. AGM should be charging at around 14.7 or 14.8 V before going to float around 13.?V.

[Mr B]

I have pulled the two FLA batterys out, I think one or both is cactus,
Charging the AGM's to see what happens, started charging at 12.4
They were all on 11.7.

[Wotname]

Originally Posted by Mr B

.....
Charging the AGM's to see what happens, started charging at 12.4
They were all on 11.7.

What are you using to charge them; Shore power or something else?

[Boatyarddog]

Originally Posted by Mr B

Coming from Fiji to OZ,
I had 360 watts of solar panels on board. 2 x 100 watts and 2 x 80 watts,
I had a 913 Rutland wind generator,
Two X 200 amphr lead acid batterys, 400 amphrs total,
I never ran out of power running every thing 24/7.

I now have 500 watts of Solar panels, 2 x 250 watts each,

600 amphrs of AGM batterys and 2 x 160 amp lead acid start batterys, ,
I bought the lead acid batterys as my AGM's died overnight, While moored,
I had motored for over 24 hours running on the alternator on the diesel the day before,

And a wind generator from china, I basically havent used it yet as there has been no wind, It was cheaper than a new controller from Rutland which I accidentally drowned,

Even with every thing turned off, The batterys still drain overnight,
My alternator is new and I believe it pumps out 50 amps,

The only thing different is the AGM's instead of lead acid batterys,
I run a freezer full time, which draws 2 amps,
In the marina I kept it on 240 volts thru an AGM charger that turns off when the batterys are full, 12.4 volts,

Sailing, Its on the solar panels and the diesels alternator, Which both do charge the batterys,
But they still discharge over night, Like some thing is on and pulling lots of amps out of the batterys,

I checked the solar panels, They have 2.3 on all the connections between the diodes,
A really big wave crashed down on them, But inside the box its bone dry and never had water in there,
But have an error on the leads out from the panels and from the panels to the diodes, On the multimeter,
But the panels still charge the batterys, ???????
The diesel still charges the batterys,

All the AGM batterys are new, 200 Amphrs, 2 x 6 months, One 12 months,
The two lead acid are about 9 months old, Max. 160 Amphrs each,

Solar is thru a Controller with a circuit breaker for a fuse, next to the batterys,
The batterys are currently 11.7 amps. So basically dead,

Does the Diesel alternator kill AGM batterys,
Will the wind generator and controller kill AGM batterys,
Will the Lead Acid and AGM's tied together kill each other,

All my batterys are in the one bank and 12 volt,

Would I be better buying new lead acid batterys or getting more AGMs.
I bought the AGM's for convenience as they dont need to be maintained, Water added weekly,

Keep it simple, Please, as I dont understand electrics,

All help appreciated,

Thanks, Brian,

Keeping it simple is the key.
A fully charged battery is 12.65 v.
Disconnect each battery and check separately.

Each battery should be of similar types, all agm or all lead acid.
Agm, and lead acid have different charge programs.
Whatever your charge source is it must charge the batteries using the same charge program.

Lead acid batteries, while somewhat messy, allow more spot diagnosis than most others, so IMHO, are more simple.
Each cell in the Lead acid batteries can be inspected, using a hydrometer.
Simple device compares specific gravity in each cell.

Each cell in a 12 vt. Battery is 2v x 6 cells so 12v.
All cells when checked after fully charging using a hydrometer, should be identical to each other or very close.
You must check these cells after charging, not adding any water before as this dilutes the solution.
Compare each cells reading, and any cell in a bank of 6 that is visibly lower is suspect.

AGMs read differently.

Seems as though some of your multimeter readings are on AC settings.
Should all be DC reading through your multimeter
Charge controller pictures looks like corrosion on the controller, and don't look to be charging your batteries as seen on the display face.
But, you knew that.

Disconnect all batteries, and allow to set overnight disconnected from each other, then perform tests on each battery separately.
You'll find 1 that is reading less than the others

You'll find that usually only 1 battery will be bad, charge and LOAD test each battery, separately, not as a bank.
If there different makers or ages they are suspect.
Certainly, AGM and lead acid should never be mixed due to different charge programs.

SV Cloud Duster

[garychurch]

If your charger stopped charging at 12.4v you have a charging problem that undercharged the AGMs. The AGM should be charged at about 14.4v (Lifeline Recommendation) for bulk charging. Then decreasing during absorption to 13.6V for float.

Do not mix FLA and AGM batteries as mention and get yourself a proper AGM charger that has the correct bulk, absorption and float profile.

You may be able to resurrect the AGMs if you properly charge them.

Good luck.

[CarlF]

I'm afraid you are another victim of the cruiser's AGM scam. They should never be recommend as house batteries for cruisers who don't plug into a slip at night. As others have said, AGM's can die within a year if not fully recharged to 14.4V every day or so. It's called Partial State of Charge (PSOC) sulfation. It sounds like you don't have enough solar and wind to do this.

FLA batteries are much less prone to PSOC than AGM and cost much less. So I would just buy new "deep cycle"FLA batteries. These are available everywhere. Golf Cart batteries can be an excellent choice. Or combining pairs of Trojan T105 6v batteries to make 12v.

You can use one big bank if you are careful to not run it down too low to start the engine. Of buy a truck or auto 12v start battery FLA for engine start. One marked 700 CCA should be powerful enough. Run all your charging to the house bank and then keep the start battery charged using an inexpensive automatic charging relay (ACR)

Set all your charging sources to the new battery specified Absorption and Float voltages (for FLA often 14.8V absorption and 13.5V Float). Remember to check the water level in the batteries every few months.

[pitlaw]

As suggested you cant mix wet with dry battery types. You may have one bad cell or two. Might be in the Wet flooded batteries. Then that bad battery would draw down the good. Its unlikely that the alternator or solar has anything to do with the depletion. Running the alternator 24 hrs should and probably did charge up the Mixed bank but a short inside depleted them overnight. Charge up the AGMs on shore power for 24 hours after taking out the wet batteries. Let them rest an hour. Where are they after that? As suggested you can check the wet with hydrometer after charging them up to 12.6.

This assumes you can set your charger to AGM profile to AGM if its a smart charger. Your AGMs are fairly new and should be ok. The brand? Read your battery manual to determine correct charging.

[smac999]

You really need to get a battery monitor on this boat.

It sounds like you are not sure if anything is charging. Or if anything is draining. A battery monitor like a victron 712 is so usefull for knowledge.

[Mr B]

Originally Posted by Wotname

What are you using to charge them; Shore power or something else?

50 Amp Diesel Alternator. It does charge the batterys,
500 Watts of solar power, It does charge the batterys when the sun is out,

Im Moored in the Towamba river near Eden, No shore power,
Its a Multihull mooring only, 4 feet deep getting into the river,

I did have a specific AGM battery charger connected up to the batterys when I was in the Marina and tied up to the wharfe at Eden,
It took the batterys to 14.4 Volts,
It shuts off when the batterys are charged,

The two lead acid batterys are definitely Kaput, They have a red light indicator in them and both are red,

Im currently running on the diesel alternator and the AGM batterys are currently on 12.70 volts after running for one hour.
I will run the diesel for a couple of hours to see what happens, ???????

I will the disconnect the battery bank and check each battery separately,
I have 3 X 200 amphr AGM's,
They started the Diesel easily, so cant be too flat,

Thank you all for your help, Its much appreciated,

[Wotname]

Originally Posted by Mr B

........

Im currently running on the diesel alternator and the AGM batterys are currently on 12.70 volts after running for one hour.
I will run the diesel for a couple of hours to see what happens, ???????
..............

Still keeping it simple, with your alternator you will likely need to run the engine from 12 to 36 hours to fully charge 600 Ah of AGM.

If they have been left partially charged for days/ weeks, then they are probably on their last legs already; but with some luck, they might still be reasonably good.


Sorry to be the bearer of bad news...

[Mr B]

I started off on the wrong foot any way,
Ignorance on Batterys, And no one to ask that knew what they were doing,
I have asked a lot of electricians to check it all out, But they weren't interested or didnt do boat visits,
Lugging 74 KG batterys around isnt all that easy, From a boat to a workshop,

I used the two batterys out of my RV in my boat,
One FLA 200 amphr of unknown origin and age, 18 years old I think it was,
One AGM of 200 amphrs 6 years old,

Both were dead at Port Albert after running 24 hours on the diesel,
I bought the two FLA 160 amphr start batterys there as I was up the creek any way,
That was all I could get delivered to the pier,
Unfortunately, I added them to the bank with the dead batterys,
So killing them all,
The red lights have been on for a while,
I turfed the two big batterys,
Still not knowing, I added the 3 new AGM's with the two dead FLA batterys,

So now Im down to the 3 x 200 amphr AGM's, 12.97 after 2.5 hours on the diesel,

I might just get 3 new x 200 amphrs of FLA batterys and start from scratch,
They dont seem so troublesome as AGM's, Due to charging issues,

Im still not sure whether the Diesel Alternator is killing the AGM's or not,
Its a totally rebuilt very old diesel alternator,
I have also read that the old alternators wont charge AGM's.
Thats totally out of my forte,

I also read on one of the ebay sites that the new chinese wind generator I bought wont charge AGM's, ?????????

Cheers Brian,