Stuck in Mexico: need advice

[GrowleyMonster]

I am a huge fan of golf cart batteries. I could write a book on all the reasons. Short version is my smaller boat is electric, and the bank is 48v, 220ah, for 10.56kw/hrs consisting of eight GC-2 6v golf cart batteries in series, $85 each from Sams Club. They are now over 4 years old and holding up nicely. I do not have a 12v bank on that boat nor any 12v starting battery obviously, since the engine is electric. Golf cart batteries are pretty cheap for what you are getting. The hitch is you need to understand them and their optimum charging algorithms and how to monitor and maintain them. The good news is it isnt rocket science or brain surgery, and shouldn't be too techy for even a liberal arts college guy. WTF is liberal arts, anyway? painting campaign posters for Democrats or something? LOL sorry I had to pull that string, having dropped out of high school making more than our family lawyer made in a year, shrimping. I guess I get impatient with folks who can't just figure stuff. out and I shouldn[t be that way. And I should also stop spilling bourbon on my keyboard. But anyway what they said. If you have a bunch of 12v batteries in parallel, Isolate them and charge them separately, and use them separately. Get Nigel Calder's excellent book on sailboat electrical systems. Get a meter. Find the thing that pulled your batteries down. It might be a shorted cell or two in the "bad" battery.


The beautiful thing with FLA batteries is you can equalize them. This SOMETIMES brings a non performer back up to usefulness. Done regularly, it helps correct sulfation and stratification, and extends battery life. I do mine twice a year. Some guys do it monthly but I personally suspect equalizing so often sheds excessive amounts of active material from the plates and could thereby shorten useful life. Depends a lot on how you use them. Deep cycle batteries LOVE to be rocked a bit. And used/charged moderately, not left abandoned and unloved on a boat that sits at the dock and gets little real attention. Stratification is one of your enemies and poor usage/charging patterns leads to sulfation which in extreme cases can be not entirely correctible.


True deep cycle batteries can tolerate a FEW discharge cycles that deep. In fact, annually it is maybe a good idea to do a full discharge to calculate capacity. But generally with FLA batteries you do not want to discharge routinely below 50% State Of Charge. Now and again discharging to 40% or even 30% is not death to batteries but avoid it as practical and possible. So this means you need to figure out how to track how much juice you are using, and unfortunately it is not as simple as amps times hours, except right exactly at the 20 hour discharge rate. Google "Peukert Effect". So gosh you have to actually open some books, view some web pages, watch some youtubes. Sounds complicated, huh?


Most other types of batteries are simpler. The good news is you don't have to do so much. The bad news is, you CAN'T do as much. You typically CANNOT equalize, as an example. You CANNOT check electrolyte level or specific gravity. You CANNOT do much to extend useful life beyond what ignoramuses who can't be bothered to learn batteries get out of their banks.



Not knocking AGM, Gel, non-lead types, etc cause they have their pros and their shining moments but well, you are not the master of those batteries, They are the master of you. They quit when they are darn good and ready to do so. This can be a long time but typically is not so long at all. Best quality FLA batteries can last as long as 20 years and often go 10, with true deep cycle batteries. But they won't last without proper care and you must learn how to maintain them to get superior lifespan and performance out of them.


But okay, back to your AGMs. Isolate them and try to charge. If 6v, isolate them of course in pairs, assuming a 12v charger. Charge them hard, or if a smart charger then just trust it to do the right thing, I suppose. The ones that won't cut it, see the end of the post. Meanwhile just eliminate the bad one.


Okay I forgot where I was. Oh yeah batts that won't charge or have very low capacity. Unfortunately with Gel cell or any sealed battery, you can't equalize. Don't do it even on a dare. With FLA batteries, google about equalizing. And take a piece of big pipe and lay it on the dock. With face shield and rubber gloves on, rock the problem battery on the pipe to stir it up and hopefully break any bottom short within a bad cell. On the rare occasion, this works.


I know folks have done this successfully, but I do not like the idea at all of mixing battery types. Or for that matter even different brands, or even different batches or build months. IMHO best to keep them separate, isolated with A/B switches, etc. I don't care for diode isolation though many other sensible sailors do so YMMV.



It really sounds like a good time to switch to golf cart batteries or else high quality 8D's.

[Silverbullet]

Battery science isnt complicated so relax. Im a solar professional of 35 years. Just to have gotten you out of a jam, Wal Mart has a seasonal marine deep cycle battery sale every fall. Usually priced at $69.95 each. Dont know if its still on but they will ship to your nearest store if they are out of stock. Bringing back conventional batteries to life requires charging up to at least 12.5 vdc. Then put a load on them, I use an automobile headlamp, and recharge. If you can see a cell that is not bubbling, you can restore it by placing the negative wire, just a piece of scrap wire on the charger clamp and drop in that cell. Put the positive in its normal position and charge until you see bubbles for several hours. "Dead cell" is generally crud on the plates of that cell and this will cause them to drop off. Place the leads from the charger in position b4 you even plug the charger in. Gas from charging can explode! My choice number one would be to check online for Wal Mart sales. If there is a Harbor Freight nearby you can buy one of those 1000 watt jennys and some fuel, although I dont normally have gasoline on board, and make it home. You can catch me on FB at Samuel Hay if there is anything I can do. HA..just thinking back in the day, we had no power on board..lol Only small batteries for lighting. DISCLAIMER: Proceed at your own risk. I am an active 76 year old.

[john61ct]

There are **no** proper deep cycle batteries sold at 12V in Walmart, any other big box retail or auto channels that I've come across, they use that term fraudulently.

And not all 6V GCs are as good as those Duracell / Deka's FLA.

Everything at this site is worth deep study

https://marinehowto.com/what-is-a-deep-cycle-battery/

[gpeacock]

Originally Posted by jenders

All: Thanks to everyone for the input. I've had all my batteries load tested and none are holding a charge under load. I'm driving to Phoenix to replace them. Still have no idea why they all were fried. The outer walls began to collapse, like they were sucked in, which I'm told signifies they were overcharged. I have two 85 amp solar panels, and a Blue Sky charge controller, which I assume should have stopped any possibility of overcharging. Still trying to figure this out. What I need is a full electrical system audit. Anyone know anybody in the Baja area who does such things?

Hey Jenders.
Like a few others have said. LTH 6 Volt Wet cell FLA is the way to go in Mexico. They are easily available and are quality batteries. Having spent a few summers on the hard in Guaymas I know your pain. The first season our boat hit 60 deg C regularly. Thats very hot for battery storage even if they aren't being used. Add a solar trickle charge at a slightly in correct voltage into the mix and you'll see them bulge for sure. AGM's are especially sensitive to this abuse because you can't fill them with liquid if it boils off. If you are planning on spending any further summer seasons on the hard in the Sea of Cortez, I'd suggest you save the boat unit and just get what you can get at the nice store just around the corner from the Fonatur. The Autozone in town is another option. Put a call out on the crusiers net there or in San Carlos for help with the audit. There are lots of knowledgeable cruisers there. Or post specific questions here. There are lots of armchair sailors waiting to pounce.
Enjoy Guaymas. Im on the other side of the world now but think of all our friends there often.
Gary

[Silverbullet]

Originally Posted by john61ct

There are **no** proper deep cycle batteries sold at 12V in Walmart, any other big box retail or auto channels that I've come across, they use that term fraudulently.

And not all 6V GCs are as good as those Duracell / Deka's FLA.

Everything at this site is worth deep study

https://marinehowto.com/what-is-a-deep-cycle-battery/

Paying double or triple for batteries for a sailboat is a questionable practice in my opinion. You are paying extra for 1500 cycles at 50% Who does that? Age will kill a battery for example the plates can become coated with age to the point of ruination. I have six marine deep cycle batteries on my 12 panel 250vdc solar array. I have 8 boats with marine deep cycle batteries. I dont seem to have any problems. I do exercise all of the boat batteries regularly. If I was driving a solar automobile, I would have probably 50 or more lithium batteries on board. Your expensive sailboat batteries will discharge on their own if not in use/recharged. And in most climates of higher temps they will self discharge rapidly. There is no assurance that any type of battery's life is not sorely affected by total discharge. In cooler weather the batteries will discharge themselves at a slower rate. But remember the colder weather will make an engine harder to turn over resulting in many people replacing their battery! If you take a cold battery that seems dead and bring it to a warm environment it will bring it back to the point where it will start the engine.

[john61ct]

Originally Posted by Silverbullet

Paying double or triple for batteries for a sailboat is a questionable practice in my opinion.

$1 / AH @12V gets you the Deka GCs, well known for being true deep cycle quality.

There is no such thing as "coated with age". Obviously when stored need to be floated or topped up every few weeks.

Plenty of top quality banks **properly cared for** last well over 12 years.

I agree spending much more is silly if you don't have the gear and knowledge to care for them properly.

And what I'm talking about has nothing to do with Starter batts, yours are fine, trivial use case.

The topic here is House bank storage, runs your climate control, fridge & freezer, screens and stereo, all the stuff **other** than starting the engine. Say 300-1500AH, often living off-grid for weeks even months at a time, maybe travelling to remote, primitive locations.

[Silverbullet]

I used my example of my whole house solar array. My system is five times larger than most any sailboat. I have cut batteries apart that I couldnt bring back to life to see what happens. Dont take my advice, Ive only been around for 76 years and Im still here.

[Silverbullet]

PS: I built my first solar system in 1969. I have more experience with these systems than almost anyone else on the planet. Yes, I was a solar pioneer. I have owned solar companies, manufactured equipment and installed tens of thousands of systems. You go your way and I'll go mine.

[SKG56]

https://www.amazon.com/Boatowners-Me...trical+systems

[mikereed100]

If you find yourself shopping for AGM batteries in Mexico, it may be worth looking for a solar supply store. They will sell deep cycle AGMs that would be suitable for your needs. The AGMs that LTH sells are starting batteries, not deep cycle. You can buy Optima batteries at LTH and Autozone (both LTH and Optima are made by the same company, Johnson Controls) but they will be very expensive. If you go that route look for yellow or blue tops as they are marketed as "dual purpose" rather than start only. I think you will be much better served looking at solar deep cycle batteries, though.

Also, keep in mind that the helpful folks at the local LTH distributor know less about batteries than you do and will happily insist there there is no difference between rapid discharge and deep cycle batteries.

If you plan to spend another season in the Sea of Cortez and will be storing your boat in the off season, you might consider simply removing the bad battery, dealing with a smaller bank this season and then storing the boat in Puerto Penasco next summer. You can then bring new batteries with you in your own car when you return, or take the shuttle to Phoenix and pick some up.

[Eder]

It is easy to buy the batteries in San Diego and get them shipped anywhere in Mexico in 3 days...tracking number included...when I used the service the cost was 10% of invoice price total...no duty.

[zeehag]

ye know , it is sooo very easy to find and buy batteries in mexico. just different brand names but they are good batteries. sad so many immediately go to the first most expensive alternative they can find..if it aint pricey it aint right..hahahahaha guess what..... mexico has battery manufacturers and you can buy whatever kind of battery you most crave right here in mexico. the core charge is more reasonable than that 3 usd in usa that is allotted, and special orders are filled with smiles and no duty.
funny how gringos refuse to support the nation in which they allegedly love so much for cruising.

[hellosailor]

" They said regular chargers absolutely will not charge the batteries when this low."
In the US, for the last 15-20 years or so, most chargers are made so that they will NOT charge any battery that is below 10.5 volts. This is by intent, because folks keep trying to charge dried-out batteries and blowing them up, and the charger companies got tired of hearing about it. Automobile alternators are often set up the same way.
Old fashioned "dumb" chargers will still work, but at least in the US, you can't assume any conventional charger will work with a really dead battery.

If the OP hasn't bought new batteries yet, the best thing is to separate them all, and try charging them all up individually, then seeing which ones really can or will hold a charge--or just pretend to hold a charge. Depending on how long they were at that low voltage, they can all be toast. If he's lucky, they aren't. But first, asses the damage, then worry about rebuilding.

[Eder]

Originally Posted by zeehag

funny how gringos refuse to support the nation in which they allegedly love so much for cruising.

Trust me Mexico has lots of my pesos over the years. No sense paying double for Lifelines though...I spent the $900 I saved at Tacos on the Street haha.

[SV THIRD DAY]

Originally Posted by jenders

. What I need is a full electrical system audit. Anyone know anybody in the Baja area who does such things?

Come to La Paz...
Have Will at TechMex services go over your system. If you dont have a battery monitor you need one. Im amazed at how many cruusers dont.