Intelligent lead-acid battery choice

[snotter]

Originally Posted by john61ct

If you really aren't willing to adapt to the GC form factor, then Trojan 12V at least you know true deep cycle.

John, are the Trojan SCS200's a true deep cycle? If they are what Maine Sail calls a true deep cycle I think that is the way I should go. Also, if the SCS200's have more room above the plates, they would be better at surviving healing when sailing on the wind since there would be more water to keep the plates submerged.

[snotter]

Originally Posted by ranger42c

Why did you mix G31s and G27s? Was the second group of 3x G27s because of a space limitation?-Chris

Because I didn't know any better 10 years ago. That it isn't a good practice is why I want matched cells.

[snotter]

Originally Posted by ranger42c

6x Firefly AGMs would also be about 600 Ah and might address your wet cell exposure issues under sail...
-Chris

I am not willing to spend the big bucks until after I get around to move the bank outside the engine room. When I do, Perhaps I will buy 5 Fireflys--that would be all I would need if I cycled them to 20 or 30% SOC. However, not at this time. Who really knows what the life expectancy of Fireflys actually are?
Perhaps in 4 to 6 years lithium will become mainstream and much cheaper.

[ranger58sb]

Originally Posted by pcmm

The stock battery box on a Morgan 415 ( I have one) holds 4 6v Golf cart batteries. Just go to Sam's club and buy them. They're $85 a piece.

Originally Posted by snotter

The batteries are too tall for my box.

Originally Posted by snotter

Because I didn't know any better 10 years ago. That it isn't a good practice is why I want matched cells.

Fair enough, Rome wasn't learned in a day.

Seems odd that PCMM says GC2s will fit. Something Morgan did between years?

In any case, perhaps a non-traditional solution can still work, in one of two ways. A64 has said elsewhere that he has Lifeline GPL-4CTs (6V batteries) on his boat because they're slightly shorter than "standard" GC2s... whereas the "standard" version would be too tall... so perhaps that could be worth investigation.

Or if that doesn't work... you can install AGMs on their side... so AGM GC2s could maybe work that way?

-Chris

[Stu Jackson]

Originally Posted by snotter

One day I will put either fireflys or GC2s under a settee in the main cabin. However, I am not willing to do that for this go around.

So you've essentially answered your own question, haven't you?

You KNOW the limitations of putting batteries in a hot engine space, but have chosen to NOT resolve that issue now.

You want to keep costs down and don't have height for GCs.

Your least expensive option, not that you have allowed yourself any, is to replicate what you have and fix it later.

What's so hard?

[ArmyDaveNY]

Originally Posted by NakedCity

Please do yourself a favor and search out a technical bulletin issued by Smart Gauge that is titled "Interconnecting Batteries"

Here's the link:
SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

[a64pilot]

The GPL-4CT is 9.92" tall, call it 10"
The GC2 is I believe 10.38" tall

[john61ct]

Originally Posted by 70AMX

There is talk at the RV forum about the Interstate batteries at Costco now being made by Trojan.

That would be fantastic for consistency and general build quality, but note wrt lead,plate thickness, these 800-lb gorilla OEM customers do force the actual manufacturer to build to their price.

So even if you believe a Trojan branded unit is better quality than the Deka equivalent, doesn't mean the Costco would necessarily last longer than the Sam's.

Rigorous testing would be required to know for sure, or waiting to accumulate years of anecdotal reports.

I'll stick to recomending the Deka/East Penn Duracells in the meantime.

Originally Posted by a64pilot

Sams Club is Walmart, I believe.

Le Méridien is owned by Marriott, doesn't make them equivalent.

[ranger58sb]

Originally Posted by a64pilot

The GPL-4CT is 9.92" tall, call it 10"
The GC2 is I believe 10.38" tall

Didn't realize it was such a small difference...

I wonder if that maybe means various other GC2 brands dance around that 10" height a bit here and there?

-Chris

[john61ct]

Originally Posted by snotter

John, are the Trojan SCS200's a true deep cycle? If they are what Maine Sail calls a true deep cycle I think that is the way I should go.

Yes they are, Trojan clearly mentions cranking duties and specs for its "dual-use" compromises. Unlike the scammers marketeers in the big-box 12V arena.

WRT the plate exposure maybe look at true-DC AGMs from Trojan if they have them, probably not much more cost per AH?

Maybe ​Lifeline, Northstar, Odyssey have lower-tier but still good AGM lines?

[ranger58sb]

Originally Posted by john61ct

Maybe ​Lifeline, Northstar, Odyssey have lower-tier but still good AGM lines?

Can't imagine any of those three specific brands being thought of as "lower tier" compared to Trojan...

-Chris

[john61ct]

Originally Posted by ranger42c

you can install AGMs on their side... so AGM GC2s could maybe work that way?

Yes another point in AGM's favor.

Don't need to be GC2. any form factor AGM, long as they're true DC, not "dual-use" cranking.

GC2 just happens to be cheapest known-good (only?) true-DC in normal retail.

[john61ct]

Originally Posted by ranger42c

Can't imagine any of those three specific brands being thought of as "lower tier" compared to Trojan...

-Chris

No, I just meant they may sell a reasonable price AGM line below top-tier pricing.

I don't know Trojan's or other AGM lines at all.

[a64pilot]

Originally Posted by ranger42c

Didn't realize it was such a small difference...



I wonder if that maybe means various other GC2 brands dance around that 10" height a bit here and there?



-Chris

In my box, the batteries actually hold the cover panel up about 1/16"
An additional .4 " would have been just way too much. When I need to replace these, if I don't go Life-PO I may cut out the box and make it an inch deeper, and use GC2's.
I believe back when my boat was built that Gels were the battery of the future and that is what was fitted, but as the boat came with a "dumb" charger with no float, they were doomed.

[skipgundlach]

Originally Posted by a64pilot

In my box, the batteries actually hold the cover panel up about 1/16"
An additional .4 " would have been just way too much. When I need to replace these, if I don't go Life-PO I may cut out the box and make it an inch deeper, and use GC2's.

(clip)

My trojans that I replaced my Deka L16 with are both taller AND have a hard handle which means my parallel links are over them.

My battery box is a shoebox cover with 3 2" straps to hold in place in the event of a knockdown or roll.

So, the cover was contacting my hyrdo-caps, and the parallel cables over the touching too-tall handles.

I cut the 8 x 1.59" tall supports from 2x2 furring studs and placed them about at the corners. I now have firm support, and the top still goes over the sides.

That might be an answer for your case, too...

L8R

Skip