Battery Issue possibly?

Jun 1, 2019
21
Oday 30 Saugatuck
My beloved underpaid Sailboat Forum. I need your help again!

I’ve always had issues with my batteries and electrical.

We replaced the batteries with two brand new batteries last year, here was the rundown today, which has happened before:

The trickler/ charger was off all week so when we showed up this weekend, we had to charge for about 3 hours before It would start and turn over. When it did, we idled in the dock for about 20 minutes, then shut it down for 10 minutes, Then started it again no problem.

Now we had the confidence to go out in the lake. We went out, 20 minute ride down the channel, shut it down, sailed for a bit, tried to start and we got nothing, maybe one or two turns. Had to get towed in.

So it has an issue keeping a charge or charging while under way. It sounds like a battery issue but they are only on their second year.

Any thoughts you have would be appreciated

Jim
 
May 17, 2004
5,032
Beneteau Oceanis 37 Havre de Grace
What kind of batteries? Are they true deep cycle? What kind of charger? Were any loads connected during the week? It’s common for some parasitic loads to drain the batteries slowly, but completely flat in a week sounds more dramatic. Did you check the voltages along the way to get an idea for the state of charge?
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
Jim it is possible. Batteries can be killed in short order by a bad charging system.

Checking the forum for battery issues you will find a rich volume of data on how batteries are destroyed, lost, how to charge, and other good ideas.

What type of batteries are we talking about? What brand and model of charger?

If you want to do some reading, I would recommend What is a Deep Cycle Battery? - Marine How To

john
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
I'll offer guess #1.

Assuming your batteries were fully charged when you left the boat last time, you have an unknown load on your batteries.

For your first test, open all breakers you would normally do when you leave the boat, and check for a current flow using a multimeter.

If no flow .................................... next:

1. Fully charge your batteries and check with a multi-meter for about 12.8+V.
2. Physically disconnect every electrical connection from the batteries.
3. Check the voltage again after a few days.
4. If it's down, it MAY be the batteries but don't throw them over the side just yet.

Let us know how it goes.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
And running a battery fully flat is really hard on the life span of a battery. It is best to never let them get below about 11 V.
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
Here is a recent thread about batteries and chargers.
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
The trickler/ charger was off all week so when we showed up this weekend, we had to charge for about 3 hours before It would start and turn over. When it did, we idled in the dock for about 20 minutes, then shut it down for 10 minutes, Then started it again no problem.
This is not enough time to charge the batteries to full capacity. Once the batteries have been discharged below 50% state of charge more than once, the overall capacity of the battery becomes limited.

Idling does not provide much charging to the battery. The alternator's output is related to how the regulator is set and the speed of the engine. Stock alternators with internally regulation are only good for recharging a start battery that was mostly charged before starting the engine. Stock regulators do not allow the voltage or the current to reach levels to fully charge the battery.

So it has an issue keeping a charge or charging while under way. It sounds like a battery issue but they are only on their second year.
Probably not a battery issue. Most likely a charging issue and a load issue. Old chargers kill batteries, loads from refrigeration, electronics, lights and autopilots can be a significant drain on the batteries.

Visit MarineHowTo.com and study the many articles on batteries and chargers.
 
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Jun 1, 2019
21
Oday 30 Saugatuck
Batteries: 2 Interstate Marine Cranking, 2 years old

Charger: very old would be my guess:
Shoemaker: (10amp charger, 2 amp trickle, 50 amp engine start) model 1050PE
 
May 17, 2004
5,032
Beneteau Oceanis 37 Havre de Grace
Yeah, so we’ve got some non-ideal things going on here. Those batteries, based on being for “cranking” are likely not deep cycle. So bringing them down in charge is really not healthy for their life span. With the 10 amp charger in the 3 hours you charged you put at most 30 amp hours back into the batteries, which isn’t really enough to build them back up. I am still curious as to what loads may be on the batteries over the week to flatten them, but if the batteries have reduced capacity because of being used as if they were deep cycle before, then it might not take much parasitic load to flatten them anyway.

I’d say to get a couple truer deep cycle batteries that will better handle being run down a little. You still can’t really run them down very far or leave them at a low state of charge, so you’ll want to check on the load situation too.
 
Apr 11, 2010
946
Hunter 38 Whitehall MI
you might want to consider a more modern appropriately sized current technology battery charger that you can leave on when boat is in the slip.
As others have already said it appears you have cranking batteries which are great for starting the engine but not for the duty of running refrigeration, instruments, or other devices on the boat. Cranking batteries provide higher cold cranking amps but do so for a much shorter time than the power a deep cycle provides.
 
Oct 24, 2010
2,405
Hunter 30 Everett, WA
Your description of the charger sounds like an automotive charger. Not good considering the demand of a marine system. They also aren't usually safe in an un-supervised environment, and likely overcharge if left on indefinitely. That alone could be the ruin of your batteries. Pick up a digital multimeter. They are cheap these days. Never let them get below 12.1 volts unloaded. With your new multimeter you can also see if your alternator is charging (significant voltage increase while the engine is running.)

Ken
 
Sep 25, 2008
7,077
Alden 50 Sarasota, Florida
My beloved underpaid Sailboat Forum. I need your help again!

I’ve always had issues with my batteries and electrical.
a
If I can make a suggestion as you seem to be having some fundamental issues with electrical systems on a boat, seek some local advice from a marine tech or boating friend knowledgeable in the subject to thoroughly go over with you what you have. Alternatively, there are some basic primers you might want to read before wasting more money on the wrong batteries or a charger inappropriate for use on a boat.
 
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Likes: Bob S
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
Before spending any more money on batteries, it is time to think about and assess your electrical needs. Most batteries marketed as "marine deep cycle" batteries are not really deep cycle batteries. See this article on deep cycle batteries. "Marine Cranking Batteries" are probably good or the run about or ski boat, but not so much for sailboats.


Next it is time to assess the electrical needs. Some refer to this as an energy budget. What electrical loads are on the boat? How much current do they draw? How long are they on? This will tell you how much battery power you require for your sailing. From there, you can purchase appropriate batteries.

With all electrical systems, charging is key. Modern chargers are temperature compensated and are multistage chargers, i.e., they vary the charging current and voltage to properly charge the batteries. Your battery charger is not designed to encourage battery longevity.

There is much to learn about electrical systems, MarineHowTo.com has many articles about this topic. One common fallacy is that if you draw out 10 amp hours from the battery it is only necessary to put back 10 amp hours. Due to several factors, it is always necessary to put back more amp hours then are taken out.

Those Group 24 batteries have at best a 70 amp hour capacity. Assuming a 50% state of charge (SOC) it will take many more amp hours than 35 to fully charge the battery. As a battery approaches a full charge, it accepts less charge and it takes longer to reach 100% SOC.

This is just a quick and dirty Sunday night rendition of basic battery care.

The really short story is you will need a better battery charger and the alternator should be checked to make sure it is working correctly. Take it to a good automotive electrical shop, one that services starters and alternators.
 
May 24, 2004
7,129
CC 30 South Florida
I don't know how you manage your batteries but you need to start with the proper components. Those "Cranking" batteries are not deep cycle, their plates are thinner and designed for short bursts of power and immediate recharge. They do not take kindly to deep discharge cycles. A trickle charger is not an adequate charger to recharge a deeply discharged battery. What I see is possibly sulfated batteries from insufficiently recharged batteries over a period of time. My recommendation would be to take the batteries to your local auto parts retailer and have them tested. They will check state of charge and test the capacity under load. The batteries could have diminished cranking capacity but they might still be good for automotive service. Maybe whoever sold you the batteries may prorate their value if you purchase two Marine deep cycle batteries. Get rid of the trickle charger and install a smart charger of at least 20 Amps. A smart charger with 3 stages will provide Bulk Charge up to around 70%, Absorption charge up to 90-95% and Maintenance Charge up to full charge. Batteries have a declining acceptance rate as they work towards a full charge and a smart charger will lower the charging current accordingly. This results in that the average battery takes approximately between 4.5 to 5 hours to recharge to 100% capacity. I don't want to ask why your trickle charger was off all weekend, but it worries me that you may be turning it off before you leave the boat. I know of no one that will stay at boat for 5 hours to watch the batteries recharge. We keep our charger on 24/7 while hooked up to shorepower. The useful life of a battery is dependent on that they are charged back to 100% after every use if not the plates will sulfate and reduce their capacity to hold charge . Batteries should not be discharged beyond 50% of their capacity. Periodically check the electrolyte level and only add distilled water when needed. Batteries should last approximately 5 years. Last observation, manufacturers have not been able to determine why some batteries may last only a few weeks while others may last 5+ years. Because of this the battery warranty industry has bee developed. You may purchase the same battery at three different prices and getting the higher priced one does not mean you get a better battery, just a better warranty. I usually go for the cheapest warranty as usually if a battery lasts 6 months to a year the chances are it could last 5.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
Batteries: 2 Interstate Marine Cranking, 2 years old

Charger: very old would be my guess:
Shoemaker: (10amp charger, 2 amp trickle, 50 amp engine start) model 1050PE
You have a number of issues, incorrect battery type for the usage, apparent parasitic loads and a charger that can actually be flat out dangerous if not used in the temporary fashion it was intended for. I would urge you to find someone local who may be able to help you out with this.

You really need to be using a smart "Marine UL Battery Charger". The Marine UL listing is critical as the article below will point out.

You are using an un-regulated constant current only automotive charger. Schumacher calls this "not-automatic" and there are numerous issues with this. The main one is that it's unregulated and will over charge your batteries if left unattended. The manual for this charger makes this perfectly clear.



Installing a Marine Battery Charger (LINK)




.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
This results in that the average battery takes approximately between 4.5 to 5 hours to recharge to 100% capacity.
Even the fastest charging lead-acid AGM batteries take 5.5 hours at a charge rate of 0.4C, or 40A for a 100Ah battery, to charge to 100% SoC and this is from 50% DoD. If we drop that charge rate to .1C or 10% of Ah capacity that time grows to well in excess of 6 hours to go from 50% SoC to 100% SoC. Deep cycle flooded batteries typically take in excess of 7.5 hours to go from from 50% to 100% and as they age the time to full only gets longer.

It sounds like the original poster was down at 0% SoC (10.5V) or lower, which for a starting battery, is a huge negative impact on battery life.
 
May 17, 2004
5,032
Beneteau Oceanis 37 Havre de Grace
Battery cable? Looks like 10 awg?
I think the main cable goes off in the shadows on the lower right. It looks like there’s a heavy gauge black cable coming off the top of the left post. The smaller gauge wires do look like they could use some TLC though. I see a mix of red, black, white, and brown wires. Not much in terms of fuses. One of the black wires is connected to the positive terminal and labeled +, which makes me uncomfortable. Also, I really hope I’m missing something in the shadows but it looks like that brown wire runs from the + to the -. So I guess as long we’re making recommendations on updating the batteries and charger, those wires probably deserve some attention as well to prevent other problems down the road.