I am the Boat Battery Executioner.

TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
I buy my house batteries, Grp 27 lead acid - lowest price, in pairs. I place them - once, in their position beneath the galley next to the engine.

I charge them fully twice a season - spring and fall - with an auto charger. I leave them disconnected over the winter. I check the fluid level usually once a season.

I turn the battery switch to BOTH when on the boat. No battery combiner. Most of the time I motor in and out of the harbor for 10 - 20 minutes then shut the engine down. Old Balmar dual post alt that charges a separate starting battery(which last about forever).

We go days at anchor without charging and of course weeks on the mooring (*). I check the voltage at resting state (at least 24 hours no charge), religiously, and also with light loads on. That's my sole indicator. I get a 'feel' for the batteries health.

This spring after a full charge in November, the two batteries were (independently) showing 12.5 (with a hundredth of a volt differential). With a light load the reading went to 12.4, 12.3. Hmmm,....

I could get another season out of these batteries. But I suspect their storage capacity is low. I know I wish to spend more time sailing and anchored this year, days on end, without running the engine (we often sail onto and off our anchor). I enjoy that freedom.

The problem is, I don't know how old the battereis are. They put the date stickers on the side of the battery, which is inside a plastic container (dumb). I've forgotten installing them, so I figure that's the final nail in their coffin. Out they came which I know is a one-way trip.

Sure enough, 2015. That seems to be my average over 2 boats and 30 seasons of battery brutality.

(*) I've mended my ways,...a little. I'll be trickle charging these with a small solar panel. I'm looking to keep them better charged on the mooring. And I demanded (of myself) to mark the date on the top with a magic marker(will I do it?).

Vinalhaven_.jpg
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
Well, Tom, the first step is admitting that you are a battery assassin....;)

I'm replacing my 4 6v GC batteries this year, there were installed in 2015. I'm sort of obsessed with battery health and keeping them properly charged with a smart charger and externally regulated alternator. The boat lives at a dock and is seldom free of shore power when there. Yet, I've noticed the charger working longer and harder on recent cycles.

So, don't be too hard on yourself. You may have shortened the life of the batteries by a year or so, but they lived a good, if not Spartan life. Sure, if better care had been taken you might be changing the batteries next year rather than this, it is sort like our own health care, if we ate better, exercised more, and consumed less adult beverages we all might live longer, but maybe not better. ;):beer:
 
Mar 26, 2011
3,399
Corsair F-24 MK I Deale, MD
Unless I'm missing something, I think it is obvious to you and all, that your charging resources are inadequate (sounds like you keep the boat on a mooring?). LA batteries really like to be fully recharged after each discharge and not discharged below 40-50%. I think a small (50W should do) solar system would be a good thing and would not cost much if you keep it simple. I had 200W on my cruising cat, but I put a simple 50W system on my F-24, just to keep it topped up.
Super Simple Solar



6 years for cheap batteries is not bad. Enjoy your sailing.


 
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Jan 2, 2017
765
O'Day & Islander 322 & 37 Scottsdale, AZ & Owls Head, ME
In Arizona I’m in a slip, hooked up to dock power - battery charger, no problem.
As I start to sail in Maine again I’m concerned. I’m on a mooring, use engine de minimus so the alternator probably doesn’t have time to do much recharging. I’m not keen on adding solar panels.
Would it make sense to get a portable battery charger?
Too bad you can’t jump start boats.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
In Arizona I’m in a slip, hooked up to dock power - battery charger, no problem.
As I start to sail in Maine again I’m concerned. I’m on a mooring, use engine de minimus so the alternator probably doesn’t have time to do much recharging. I’m not keen on adding solar panels.
Would it make sense to get a portable battery charger?
Too bad you can’t jump start boats.
By portable battery charger, do you mean one of those "jump packs" used to start engines? If so, then you can start the diesel with one because starting a diesel takes very little total energy, a few tenths of an amp hour. However, the jump packs won't recharge a house battery.
 
Jan 2, 2017
765
O'Day & Islander 322 & 37 Scottsdale, AZ & Owls Head, ME
That’s right.
NOCO Boost Plus GB40 1000 Amp 12-Volt UltraSafe Lithium Jump Starter Box, Car Battery Booster Pack, Portable Power Bank Charger, and Jumper Cables For 6-Liter Gasoline and 3-Liter Diesel Engines.


I'm thinking in case of an emergency.
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
With a picture like that .................... who gives a rat's ass about batteries ?


Group 27 FLA deep cycle batteries are around $85 at Walmart.
I think the 5/6 years you got is fine. Shows the benefit of using cheap FLAs rather than the latest and greatest wiz-bang $$$$ batteries.
Maybe not the best philosophy when it comes to reliability, but for penny pinching, seems like a good option.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
So two batteries costs under $200 once you add tax. If they last 5 years that's less than $40 / year.
If you only consider the purchase cost, then the argument works. However, if you take the time to calculate the cost /charge-discharge cycle or the cost per amp hour over the life of the battery the numbers go the other way, the more expensive chemistries, AGM, Carbon Foam, LiFePo have lower cost per delivered amp hour.
 
Aug 2, 2009
637
Catalina 315 Muskegon
Add adequate solar panels and check your fluid levels more often. And, be sure you have a 100% charge when you put them away.
 
Jan 7, 2011
4,723
Oday 322 East Chicago, IN
Hey,

Group 27 FLA deep cycle batteries are around $85 at Walmart.


So two batteries costs under $200 once you add tax. If they last 5 years that's less than $40 / year.

Barry
I picked up 6 volt golf cart batts at Sam’s for $68 each…after $20 each discount…215 Amp Hour Duracell (made by Deka I think).

They had 12V group 27’s for the same price, but I think they were only 100 AH.

Greg
 
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TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
No Bimini so no unobtrusive place to put them.
Our problem also. I have a space on the house that isn't trodden on, much, that I can fit a small panel(removable when needed). Most of the house top is sat on, walked on to furl sail, etc.

But our charging needs are small compared to most boats which run refrigeration (we use readily available block ice).

My main concern is taking advantage of a week or two on a mooring between use. I need to replace that last 20% that the alternator never will do without a daylong run. With our small needs the solar should help to keep us from deeply discharging while spending a few days without engine use.

I hate to plan my day (motor on), around charging batteries.
 
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Likes: AlastairLC
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
Our problem also. I have a space on the house that isn't trodden on, much, that I can fit a small panel(removable when needed). Most of the house top is sat on, walked on to furl sail, etc.

But our charging needs are small compared to most boats which run refrigeration (we use readily available block ice).

My main concern is taking advantage of a week or two on a mooring between use. I need to replace that last 20% that the alternator never will do without a daylong run. With our small needs the solar should help to keep us from deeply discharging while spending a few days without engine use.

I hate to plan my day (motor on), around charging batteries.
No need to run the motor or use solar, just strap a Honda 1000 generator on the fantail and run it during sundowner time. It will charge the batteries, run the microwave and ice maker while both annoying the neighbors and giving them a topic of conversation. "Why would anyone who sails such a classic beauty of a boat put a generator on deck and run it during the most peaceful time of day?" :stir: ;):beer:
 
Mar 26, 2011
3,399
Corsair F-24 MK I Deale, MD
No Bimini so no unobtrusive place to put them.
That is a reason to limit installation but not to prevent installation. For example, I had 200W on the hard top of my PDQ catamaran, with room for more, but I have 50W on the companionway slider turtle of my F-24 (see post#4). Completely out of the way (non-trafic area) and enough to maintain the battery plus a little more. I'd be surprised if you couldn't find a few good places.

I would not plan on removing a panel. You are more likely to damamge it in the process, and if you have to frog around to use it, you won't. that said, attach it with 3M Dual Lock and it will come off if need be (not regular Velcro--If may come off when you don't need!).
 

BarryL

.
May 21, 2004
1,000
Jeanneau Sun Odyssey 409 Mt. Sinai, NY
Hey,

I have a similar situation - boat on mooring, short engine run time, minimal electrical needs. I put this on my last boat:


It was easy to install. I would bring the panel out, connect it, and lay it in the cockpit right before I left the boat. After a few sunny days the batteries would be topped off. It worked well.

When I'm on board and sailing I remove the panel and place it in the aft cabin.

My current boat is more power hungry and has a LOT of batteries (1 for the engine, 4 for the house, 2 for the bow thruster). I bought this portable unit:
Again, easy to use. The controller mounted on the panel and swings out. The system is portable but the controlled got damaged by a rain storm. The company is sending my a new one, and i'll mount if below deck when it will stay dry.

Barry
 

TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
I picked up the new batteries and took them to my boat on the hard (waiting for launch - yard is backed up like I've never seen). Gave them their lift time lift up the ladder and put them below. Phew, it was hot in there! Opened the overhead hatches for some air. Started to wrestle them into place but it was still hotter than hell down below. I looked at the thermo in the cabin:

100 F in the cabin.jpg


WTH? This is early June on the coast of Maine. We had the heat on last week. Went home where the AC was on. It was 90 in the shade there. The batteries can wait,.... :)