Flooded Battery Failure

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Flooded Battery Failure

Postby rawill » Fri Sep 25, 2015 5:45 pm

I am now on my 3rd set of 2x6v 225 Amphour deep cycle batteries, since July 2008.
I have just put in a pair of Vision AGM batteries bought from my local RV retailer.

My issue is that the previous 2 sets (Flooded wet cell batteries) appear to have been overcharged, bulged end walls.
I am using the Morningstar Prostar 30 controller, set to the Flooded battery setting.
Max input I have ever seen is around 17 amps, max possible amps is around 30 amps, (520 watts of solar)
These batteries were sourced from Supercharge, and the last set were Crown, all sets have been 2x6v 225 Amphour batteries.
I have been told these were not the best batteries I could have bought.

For now I am thinking I should set the contoller to the gel setting.

Any comments welcome
Robin and Averil 16590 - Crusin - 1989 Nissan Condor - 28 sq meters CSC - toad 010 Micra - (1978 Mitsi Canter which must go!~!)

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Re: Flooded Battery Failure

Postby muzzanic » Fri Sep 25, 2015 8:14 pm

What about when you are plugged into 240v power, Is your main battery charger a smart charger ?

How deep are you discharging them ?

What are you running off them ?

Murray and Niki.
'Riders Retreat'
2007 Mitsi Fuso Canter 3.9 Turbo Diesel , 560w Solar, 500 A/h Lithium batteries
Maxxair Vents, 130L 12v Fridge. 240v Inverters 2500w,190L water.
We also have a second 1 of these campers with a tow bar that we rent out.

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Re: Flooded Battery Failure

Postby Mark » Fri Sep 25, 2015 8:26 pm

Ray, I think the critical thing is the voltage that they are charging at, at the various charging stages.
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Re: Flooded Battery Failure

Postby Neddy » Sat Sep 26, 2015 6:42 am

I would suspect a lot of things before your trusty, bullet-proof MorningStar solar controller, Robin.
You could switch from its 14.4 volt charge "Flooded" setting to its 14.15 volt "Sealed" setting (rather than its "Gel" 13.7 volt setting) but be sure to check other more likely causes first. Your Mains powered charger as Murray suggested, for starters.

How often do you run a generator?
What size is it?
Do you monitor it closely?
How "smart" is its controller?
What is its typical charge voltage/current?


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Re: Flooded Battery Failure

Postby mattn » Sat Sep 26, 2015 9:08 am

What you really need to see is what is the voltage doing over a long period of time. If you really want to see whats going on, you could get one of these toys.
It will log voltage and current (40AMP continuous, 130 peak) for over 30 days @ 1minute intervals. (logging at 0.2s - 3600s intervals). You don't really need to log current if you need more than 40AMP, and its shunt is quite high resistance. (They also have temperature and rpm sensors.

They are not the easiest piece of kit to use - the software provided is a bit on the "not ready for prime time" side, you need to be a bit of a geek to get things going.... but I have used mine to diagnose a few problems over the years and find it very good.
Don't be alarmed when you see me talking to myself, I am getting expert advice.


Re: Flooded Battery Failure

Postby Teardrop » Sat Sep 26, 2015 9:32 am

Flooded batteries vent and you need to replace the water occasionally. If you are replacing the water often, it may be a sign of overcharging.

On the other hand, if you have not been checking and refilling water and the fluid level goes below the top of the plates, this will cause the damage you describe irrespective of the charger. Or if you have added water that is not pure and distilled, you could have shortened the battery life significantly (especially if bore or other highly mineralised water).


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Re: Flooded Battery Failure

Postby rawill » Sat Sep 26, 2015 9:59 am

Thank you all

Hm, well I just did a double check!
I did have the controller set to "sealed" and not flooded as I said!
My 240 charger is Powertech 12 amp battery charger, (sourced from Jaycar) 3 stage I think.
I use my generator in the morning to make coffee etc, maybe 30-45 minutes, and sometimes in the evening say about 60 minutes.
If using the coffee machine it was previously a modified sinewave 5.5 generator, but for battery charging only it was a 1kw pure sinewave generator.
I have sold those and bought a 2.8 kw pure sinewave generator, (remote start etc)
Currently and historically
I only use the generator to run the 240 battery charger, I have never charged the batteries from the attached 12v charge point in the generator.

I have not been topping up the water in the batteries very much at all, maybe 2 times a year, but it was not distilled water, tank water, but sometimes bore water may have been added, we live rural, tank water and bore water when needed.

I have a large display to show the voltage, as well as the small display in the Battery monitor and controller.
I can see the large display at a glance, max volts historically (annecdotally) is max 14.5.
Now 13.8 I think on the gel setting!

However something is a bit amiss here, I want to figure it out before I damage any more batteries.
Neddy, yes, I would be very surprised if the Prostar unit was causing a problem.

Matt a voltage logger like you suggest might be something I will do, rather than rely on my observations!
Dene, hopefully it could be the top up water that caused the issue.

We run a 12v fridge, 4kw Deisel heater, TV, lights,
Max draw about 10 amps at times, usually about 4-5 when everything gets up and running on a cold day and running the heater.
When it is like that I run the generator to stop the draw being too tough on the battery, say when the heater is starting, or trying to get the van warm.
DOD, I try to use the top 25%, prefereably less, but who knows for sure, a logger would help here, sometimes I have gone lower than I want to.

Thank you all.

Robin and Averil 16590 - Crusin - 1989 Nissan Condor - 28 sq meters CSC - toad 010 Micra - (1978 Mitsi Canter which must go!~!)


Re: Flooded Battery Failure

Postby Teardrop » Sat Sep 26, 2015 10:15 am


The water would not help, but your main problem may be elsewhere. At the setting you have used, your batteries may be sulphated from undercharging. The liquid in flooded batteries stratifies (forms layers of different density) over time and every so often they should have an "equalise" charge which is normally 15.5 volts for a period to stir them up and re-mix them. This is your main protection against sulphation.


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