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Slight Bulge In My Batteries

Sep 20, 2015
106
Navigator 4200 Classic New Bern, NC
I was topping off our GC-2 batteries this weekend and found an every-so-slight bulge in the battery's casing. They are about three years old, and have really never done any real work (thanks to a variety of factors that kept us from spending much time at anchor). I have a Sterling 60A charger so I am not cooking them at all. In fact, I hope they are still near 100%. Anyway, I attached a picture. Is this something I need to be concerned about?

Thanks!
 

Attachments

Aug 22, 2017
1,580
Hunter 26.5 West Palm Beach
A bulge is bad news. Keep an eye on those batteries. Have plan B ready in case you have a sudden failure.
 

Brian D

Moderator
Feb 17, 2006
4,545
Lancer 27PS MCB Camp Pendleton KF6BL
I would replace immediately. Any bulge in the battery case is, as @JimInPB said, bad news. Don't wait. Be proactive.
 
Jul 7, 2004
6,004
Hunter 30T Cheney, KS
It means you have gas! No foolin' :eek:

Bulging batteries mean only one thing- buildup of gas inside. The gases are produced due to electrochemical oxidation of the electrolyte. Such oxidation occurs usually due to overcharging of the battery due to a faulty battery, or faulty charging electronics in the phone or battery charger.
 
Sep 20, 2015
106
Navigator 4200 Classic New Bern, NC
I don't understand how that could be. Almost zero use, smart charger with float, I assume vented caps. How does gas stay so trapped that it creates the pressure to bulge out hard plastic?
 

Maine Sail

Moderator
Feb 6, 1998
11,039
Canadian Sailcraft 36T Casco Bay, ME
With vented flooded batteries like those (Deka / East Penn) usually a bulge like that means they froze at one point. Were they left connected all winter? Did the marina lose power? How & where were they stored?
 
Oct 22, 2014
10,361
CAL 35 Cruiser Portland OR, moored EVERETT WA
Ours is not to reason why, ours is but to do or.....

How does a thick plastic container bulge out? Heat softens the plastic, and pressure adds the bulge.

If it is slight it is good that it found a way of releasing the pressure. What are the temps? Does your SmartCharge have a temp sensor attached to the batteries?

Your avatar indicates you are in New Bern NC. There was a nasty storm there in the past year or so. Could there be a connection between the two?
 
Feb 26, 2004
20,753
Catalina 34 224 Maple Bay, BC, Canada
I don't understand how that could be.
It is truly fascinating that when folks ask a question they argue with the answers from folks who are trying to help.
YOU'RE the one with the bulging battery.
A bulging battery is NOT good.
We all agree on that, right?
How that could have happened is something we ALL can only guess at.
Answer Maine Sail's questions and we might shed some light on it.

Good luck.
 
Jun 11, 2004
832
Oday 31 Redondo Beach
It is truly fascinating that when folks ask a question they argue with the answers from folks who are trying to help.
YOU'RE the one with the bulging battery.
A bulging battery is NOT good.
We all agree on that, right?
How that could have happened is something we ALL can only guess at.
Answer Maine Sail's questions and we might shed some light on it.

Good luck.
He didn't argue with the answers. He just asked a follow up question how it could happen.
 
Sep 20, 2015
106
Navigator 4200 Classic New Bern, NC
Ok... The batteries HAVE stayed connected onboard all winter(s) with a temp sensor from the charger and always full of "water" (you know... with acid and all that stuff), so it is unlikely to have over charged or cooked them like my old charger would have. We keep a small heater in the bilge all winter. Did it keep it above freezing the entire time? TBH, it's hard to know for sure, but the marina were we are now never lost power over the '19 winter season and there were never very many BITTER cold snaps this year. HOWEVER, come to think of it, there were some EXTREMELY cold snaps last year when even our four oil-filled heaters couldn't keep up. The Neuse froze 3" thick or more. People had never seen a winter like it... and I was one of those people. You know... That's probably it. Truth-be-told, I would never have thought that battery water had a low enough freeze-point to do that. I mean... if that is actually what happened.

So I guess the next question is: Did it damage them? Is there a way to know for sure that is the culprit? I have bought a specific gravity bulb to do a quick health check this weekend. But seeing I haven't really cycled them over the past few years, will that tell me anything productive? And finally, is there a way to ask these questions without sounding like I am auguring with yall's answers so I don't set off members of this board that want nothing more than to make me fell bad about wanting to learn more about this topic? :)

Tom-
 
Jan 11, 2014
4,245
Sabre 362 113 Fair Haven, NY
This article will answer most of your questions.
https://www.trojanbattery.com/pdf/WP_DeepCycleBatteryStorage_0512.pdf

Those bulb hydrometers sold in autocrats stores are not that accurate. Spend a little extra and get a
refractometer. Get the right one (see link) and you can check the antifreeze and battery.

And finally, is there a way to ask these questions without sounding like I am auguring with yall's answers so I don't set off members of this board that want nothing more than to make me fell bad about wanting to learn more about this topic?
Most of the folks here are pretty good natured, but we all get a little cranky, especially at this time of year.

There is lots of good and not so good information out there on the internet, don't be afraid to ask questions here or DuckDuckGo* for additional information. :)

*DuckDuckGo.com is a search engine that is almost as good as that other one, however, it does not track what you search and the ads you get are only relevant to the search terms. It is now my go to search engine.
 
May 24, 2004
5,932
CC 30 South Florida
Don't panic; do not recognize the battery make and some of these battery manufacturers use, How do I say, "less expensive cases". The proof is in the pudding, 1) are they taking full charge? (6.38V) 2) are they providing adequate service? (time and power). I don't practice what I preach but keeping batteries on the charger 24/7 is not good for them. It is recommended that you turn the charger off for a week every two weeks unless they have been used. I use the boat frequently so I don't pay attention to that. If you notice that the batteries are discharging significantly faster than they used then replace otherwise just ride them until they die. Replacing them now or latter basically boils down to your type of sailing; whether you are taking an extended trip or whether you are just daysailing.
 
Sep 20, 2015
106
Navigator 4200 Classic New Bern, NC
What is... sailing? Never heard that word :) (j/k... for the record, this is a 42' motoryacht)

That was an interesting document. Thanks Dave! I will take a look at the refractomenter and consider it. I always thought the cheap ones did fine, but hey, wuddo I know :)

Looking at the Trojan chart, I am sure of two things: 1) I would venture a guess that the SOC was never far below 100% and 2) it never got anywhere near minus 16 degrees... much less +19 It maybe ducked once or twice below but never when the batteries were at 20%SOC.

To Benny's point: I have never taken them off charge. Once a year I will do a plugs-out test and spend the weekend in our slip on batteries alone, but I haven't done it in a while. This is the first I have heard of taking them off charge regularly except to measure resting voltage. Moreover, I assumed, perhaps wrongly, that the maintenance/float charge from the multi-stage charger (Sterling) was the whole point of it. To never HAVE to take it off the roasting charge of the old copper behemoth that was my old charger.

Sailing huh? I am going to have to look that up and see what its like... sounds fun. :D )
 
Jan 11, 2014
4,245
Sabre 362 113 Fair Haven, NY
Don't panic; do not recognize the battery make and some of these battery manufacturers use
The photo shows the battery to be NAPA battery. NAPA batteries are house branded Deka/East Penn batteries. East Penn batteries are generally considered to be a good quality US made battery.
 
Feb 26, 2004
20,753
Catalina 34 224 Maple Bay, BC, Canada
Gonzo,

Sorry, I apologize.

I had a link to the Ample Power Primer, but it has disappeared. It's very good about batteries. If you'd like a copy, pm me and I'll get it to you.
 
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Apr 22, 2011
556
Hunter 27 Pecan Grove, Oriental, NC
I've had 3 sets of Trojan T105s over the years and they all had a slight bulge. Florida heat?? Sulfation?? They seemed to work fine.
 
Oct 2, 2008
3,044
Pearson/ 530 Strafford, NH
Same here, one battery had a bulge for two years, maybe more. It died last fall as we got into the Chesapeake and I isolated it until I could get it replaced. At our town recycling center the attendants don’t run to my truck as I pull in because they know whatever I’m bringing in aint worth crap.
 
May 24, 2004
5,932
CC 30 South Florida
What is... sailing? Never heard that word :) (j/k... for the record, this is a 42' motoryacht)

To Benny's point: I have never taken them off charge. Once a year I will do a plugs-out test and spend the weekend in our slip on batteries alone, but I haven't done it in a while. This is the first I have heard of taking them off charge regularly except to measure resting voltage. Moreover, I assumed, perhaps wrongly, that the maintenance/float charge from the multi-stage charger (Sterling) was the whole point of it. To never HAVE to take it off the roasting charge of the old copper behemoth that was my old charger.

:D )
The whole point is not the charger, but exercising the batteries. Continuous small charge currents to replace natural discharge are reported to allow for some sulfating. (I guess a stronger current is needed to combat sulfation) To be truthful I have never been able to tell the difference but like I said we use the boat frequently enough that it would not come into play. Know some folks that run the charger 24/7 for a few month at a time and they have no complaints. Do not know at what length of time the effect would significantly affect battery performance. For me I personally value convenience over $$(battery life); if it is inconvenient to cycle the charger I would leave them charging 24/7.