Leaking Battery

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LenBuchanan

Veteran Member
Joined
Jul 29, 2020
Messages
89
Location
U.S.A
Vessel Name
Feath (fee-a) Gaelic for Calm, Tranquil
Vessel Make
1989 Jefferson 37 Sundeck
Hi all,
I have a new Promariner Pronautic 40amp 3 bank battery charger that I installed at the beginning of this past summer. It replaced a Xantrex. I have no complaints about the charger but I have a question related to either the battery for my generator or battery charger.
I replaced my two 8d batteries (one for each diesel) with 2 grp 27 in parallel and replaced my 4d battery for generator, with a grp 31. All batteries are dual purpose deep cycle Duracell batteries. No problems starting my engines or having DC power for anything onboard. This replacement was a few years ago.
My question is around my Gen battery, the grp 31. It is leaking. I had battery acid in the battery box that holds the battery and I see 'wet' areas here at home as I remove all my batteries over the winter. I have looked online and the best I can determine is that it could have overcharged, causing a leak. Could that be the case?
Again, the charger was/is new. The grp 31 has a 6/22 date stamp from manuf., or Batteries Plus. I'd have to look at records to see, but believe I bought the battery new spring of 2023.
Any suggestions would be most beneficial. Thanks.
 
I fear you have a bad cell in the G31 battery. A cell that is reluctant to take a charge forces other cells to boil over. You will need a Hydrometer to measure the chemistry of each cell to determine if you have a bad cell.
 
Len: Does the “battery of concern” have “caps” for adding water? It’s not unusual to have some water on the surface of a battery that requires maintenance, if you have slightly overwatered it. Once off charge for 12 hours, what is the voltage. If you have a bad cell, it will be significantly lower than 12.7 (or 6.35 in case of a 6 volt battery) if left for any length of time.

My T-105 house bank has some water has some water around some of the caps, even the bank that was 9 years old. All cells were fine. In the case of my current bank. I pulled 4 batteries off-line, removing interconnections and left them for 48 hours and they were all within 2/100’s of a volt of one another. I put them back on line and disconnected the other 4 batteries for 48 hours+ and some thing. No bad cells.

Jim
 
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Lead acid batteries need to be kept clean and dry. The first thing I do before any servicing is wipe the tops down with a paper towel. This helps to let me know if things are different from one battery to the next battery.

If your batteries are now at home, not under any charge and you have wet spots on your floor I can't image that the liquid got there from the charging of a bad cell causing other cells to "boil over", while the battery was a car ride away on the boat.

Wash the floor with a baking soda and water solution, rinse well and dry everything including the floor and place the suspect battery up on 2 plastic supports in a plastic tray. Slide a paper towel under the Battery and that will let you know if the case is leaking.

Should the case leak, replace the battery.
 
Best to only fill battys to above the plates before charging and then top off after charged up. If you fill a batty at low SOC and then charge the bubblingbactiin can push some acid out the vented cap even if it has no shorted cells. Best to clean & dry it, ensure liquid covering the plates and put a charger on it and monitor what's going on and if leaking where is it leaking?
 
Also, the batteries shld be fully charged before watering them. If you top them off, then charge them up, they will often overflow the caps.
 
Looks like Bacchus and I simul-casted...
 

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