Don't check your batteries

[Jon and Kay]

I checked my batteries Yesterday, they have been busy working for 6 years, day in and day out.
I would not recommend anybody else check theirs because this is what I found. If only I hadn't looked

battery.jpg

battery2.jpg

[BruceS]

Ouch! Pretty safe bet cell 6 collapsed causing the other 5 cells to become 'overcharged' and cooking hot.
I guess that's a pretty good life though?
How many batteries in the bank Jon?
Ready for LiFePO4 yet?
I'm up for a couple too for my 12V bank that power just lights and a few little items like depth sounder and radio.
They were cactus when I bought the boat.

[T1 Terry]

Are they now 140Ah or 160Ah Jon? They seem to look a bit bigger than when you put them in They have been a tad hot I'm guessing due to the cells being shorted internally, the gassing seems to have stretched the cases a bit but with only 6 yrs use some on another forum will tell you they are still at the puppy stage.... you must have (ab)used them to death

[BernieQ2]

While you lot are talking battery's should I disconnect mine while we are home or just let the solar do its thing, nothings running in the m/home .
480amp AGM's .
Bernie .

[Jon and Kay]

Yes Terry, I bash my batteries up
There are 5 batteries, this is just the one I couldn't easily see. I can see it better now! (must have gone to specsavers)
Interestingly, this battery has been removed for over 24 hours , and still reads over 12.8 volts
These batteries are a good age, but I knew they were on the way out. Surprisingly, this battery was on the side of the battery bank, so not in direct line of charging or load. Do you think I have any chance of a warranty claim due to the others lasting longer?

Bernie, that would take extra energy. Don't bother, the AGMs are meant to be held on Float, just make sure the float is at the right Voltage. But who am I to give advice

[T1 Terry]

While you lot are talking battery's should I disconnect mine while we are home or just let the solar do its thing, nothings running in the m/home .
480amp AGM's .
Bernie .

13.2v for long term storage but not used or needed for instant back up power. You need to bring them up to 13.8v and hold them there till the current drops to a constant low level over 3 consecutive hrs, then they can be classed as fully charged and the 13.2v will keep them fully charged without gassing. The problem with gassing AGM batteries is the recombination device in the top of the cell converts the hydrogen and oxygen back into water, then drips it back into the cell. With no movement or rapid bubbling the acid ends up at the bottom and water at the top, stratified I think is the term, a lower charge rate will stop just about all the gassing so the water drip into the acid pool is reduced. Concentrated acid in the lower levels of the cells will eat the plates away, water has no chemicals to react with the plates so no recharging of the plates occurs so they gradually sulphate. No matter what you do, the cells will die, all you can do is delay the replacement time.

Jon, put a 60w bulb across the terminals and see what the voltage reading is after 30 mins, the load will drag out around 2.5Ah so a good battery will still read 12.8v with the load connected, an ok battery will read 12.6v, a half dead one will read 12.4v and one that has passed its use-by date will drop to less than 12.4v.

[BernieQ2]

" No matter what you do, the cells will die, all you can do is delay the replacement time."
AS with all battery's Terry regardless .
I was asking if I should just leave it as is or disconnect the solar?
Bernie .

[T1 Terry]

I thought I answered that part in the earlier bit of post, reduce the float voltage to 13.2v but it still needs to be connected to some form of charging whether it be solar or mains.

[BernieQ2]

No mate you said stuff above my head just need yes or no answer leave it on or turn the solar off .
Cant change float voltage .
So leave as is solar on ?
Bernie .

[T1 Terry]

No mate you said stuff above my head just need yes or no answer leave it on or turn the solar off .
Cant change float voltage .
So leave as is solar on ?
Bernie .

If you can not change the float voltage don't leave it charging endlessly at 13.8v or you will have batteries that look like Jon's batteries. Really, if you can't change the charging and float voltages you have a solar regulator that will kill your batteries, simple as that