Hydro Meter - 1225 reading

[rwells36]

Out of six cells contained in my lead acid 8D battery the lowest cell reads 1225 @ 74° F. The other five cells read 1275 or better. I would like to know the remaining life on the 1225 cell or if it’s likely to drain the other cells. For what it’s worth 1225 is on the border between white and red sections of the hydro meter.

[billknny]

Originally Posted by rwells36

Out of six cells contained in my lead acid 8D battery the lowest cell reads 1225 @ 74° F. The other five cells read 1275 or better. I would like to know the remaining life on the 1225 cell or if it’s likely to drain the other cells. For what it’s worth 1225 is on the border between white and red sections of the hydro meter.

Fully charged, and rested for an hour or two... what's the voltage on that battery when disconnected from everything else?

If it is less than 11 volts, you have a shorted cell and the battery is already dead.

The other possibility is an "open cell", basically a hole in the plate. This is not often seen in deep cycle batteries because of the thickness of the plates, but it does happen. This is one of the few things that would explain a SpGr difference like this.

Both of these conditions are death to the battery. You could say they are battery terminal...

[DeepFrz]

You might try equalization.

[tanglewood]

The battery is toast, or at least that cell is. Junk it. Yes, it will strain the other batteries. If nothing else, pull it out of your bank right away to contain the damage. You could try equalizing, but that's a big difference and I think unlikely to recover. I would still pull it out of the bank right away and equalize it on it's own.



Are the rest of the cells in the other batteries OK?

[rwells36]

Originally Posted by tanglewood

The battery is toast, or at least that cell is. Junk it. Yes, it will strain the other batteries. If nothing else, pull it out of your bank right away to contain the damage. You could try equalizing, but that's a big difference and I think unlikely to recover. I would still pull it out of the bank right away and equalize it on it's own.



Are the rest of the cells in the other batteries OK?

Other cells a okay. But since the battery is 5 years old I don’t think I’ll bother with equalization.

[GrowleyMonster]

Originally Posted by DeepFrz

You might try equalization.

+1


Equalize. Very likely you will see a considerably smaller difference in voltage and SG between the cells after equalizing. Personally I think equalizing a few times a year greatly improves the health of your batts and increases working life. Assuming FLA, of course.

[Cadence]

I took it as you were speaking of one 8D not one used in a bank of batteries? It is on it's way out. I don't think I would trust it long as a starting battery. If it is, repurpose it as a stand alone house battery if that is feasible and milk it for whatever you can, or just replace it.

[01kiwijohn]

Good decision. It's probably got the best part of a year left in it, but you don't know. If the others are of the same vintage, and you're planning on going cruising, it'd be wise to change them all at the same time, in the not too distant future. Much easier to do it at the dock, in a familiar town, where you can shop for a good deal, than it is to do it under duress, in a remote town, when the crew is leaning over your shoulder, wanting to know when the refer will be up and running again!