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snotter · 03-04-2017, 11:07

Once again, the batteries in the house bank of my Morgan 415 OI need replacing. In the 10 years or so that I have owned the boat, this will be the 3rd time I have had to replace my batteries.

My boat, when I got it, had two 4D, open lead acid batteries connected in parallel for a house bank. I had no coulomb counter aboard at that time and kept the batteries (they seemed to work) until a cell shorted out, causing a thermal runaway when I wasn’t aboard. Afterwards, upon coming aboard, I was greeted with the smell of sulfur and burnt wood. Moreover, all the positive battery wires from the dumb old Charles Marine charger were bare and red puddles of melted plastic were under the run of bare wires. Fortunately, the Charles Marine charger was a complete loss.

Because the 4D batteries weren’t deep cycle, and because they were very heavy, I went to a local auto parts store and bought 3 group 31 deep-cycle batteries to replace the 4D batteries. This worked fine and I kept this configuration until I discovered Main Sail’s brilliance and decided to improve my 3-battery bank. Maine Sail taught me that my supposedly deep cycle batteries weren’t deep-cycle at all. Also, I learned that adding a coulomb counter would help me keep my house bank above 50% SOC, extending battery life. Since the 3 group 31’s were still going strong, and because all of Maine Sail’s brilliance didn’t rub off on me, and since I am also a tight wad, I built another battery box and populated it with 3 group 27 batteries that I bought from my local auto parts store and connected them in parallel with the 3 group 31’s previously bought. I even let Main Sail convince me to buy a sterling smart battery charger. With the new setup connected and working. Life was sweet—at least for a bit.

After about 3 years I noticed that my 6-battery house bank was starting to show almost 3 continuous amps going into the batteries, even when the boat was at dock and the charger was in float mode. This was strange to me since the batteries use to only accept 0.3 amps. Being concerned, I checked the batteries and discovered a very hot cell in a group 31 battery. Wishing to avoid another melt-down, I went to my local auto parts store and bought 3 group 31’s and 3 group 27’s and once again life was sweet. About 2 years after replacing these batteries, Maine Sail taught me that Coulomb counters really suck at predicting battery SOC. I bought a Ballmar Smart Gauge battery monitor from Maine Sail and was pleased that it worked as advertised and allowed me to actually keep my batteries above 50% SOC.

Now that the battery bank is now 3 years old or older, the trusty Smart Gauge is telling me that I no longer have enough battery capacity to spend a night on anchor. However, this time I am not surprised I need new batteries--Maine Sail has taught me that open lead-acid batteries don’t like hot engine room spaces and that my batteries are orientated so that the top of the cell plates would be exposed when my Morgan is heavy under sail into the wind. Indeed, my only surprise is that my batteries lasted as long as they did.

Now why am I posting this thread? I want to use a little more intelligence this time when buying my lead. Since a lot of you skippers are smarter than me, I am soliciting your council. Here are my constraints: because I am not willing at this time to move the batteries out of the engine room, the new batteries are going to have a tough life; and, since I am not willing to reconfigure my battery boxes, the new batteries will be sub-optimally placed for sailing (the tops of the lead plates may get exposed when I sail); since my batteries are destined for a pre-mature death, I want to get the most bang for my buck. I have identified at least two options open to me, both of which utilize group 27 batteries: 1) buy 6 of the cheapest so-called deep cycle batteries from an outfit that can provide 6 matched batteries (same lot # and same date code); or, 2) buy 6 matched Trojan SCS200’s, at almost twice the cost of option 1. I would take option 2 in a heartbeat IF the Trojans are significantly better than the typical so called deep-cycle battery sold at Costco or Sam’s. It would please me if I could get 4, 5, or 6 year life expectancy out of my next set of batteries.

Thanks all for your wisdom and patience,
Ralph

**a64pilot** · 03-04-2017, 11:20

Ralph, can you make 6V golf cart batteries fit?

john61ct · 03-04-2017, 11:37

Make them fit if at all possible. Do not buy any more pseudo DC.

Sam's Club or Batteries+ sell Duracell branded GC2s actual mfg is East Penn/Deka.

Cheapest true deep cycling, great value. Other GC2s next choice.

If you manage to make them last this time, then it'll be worth paying for better.

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

A pricier up-front investment, but may pay off long run, is the Firefly Oasis, only lead battery that will really stand up to your PSPC abuse situation, check out Maine Sail's reports on that.

But $500 per 100AH, and you will want to give them their manual "restore cycle" every month or two.

Scot McPherson · 03-04-2017, 12:31

Quote:

Originally Posted by john61ct

Make them fit if at all possible. Do not buy any more pseudo DC.

Sam's Club or Batteries+ sell Duracell branded GC2s actual mfg is East Penn/Deka.

Cheapest true deep cycling, great value. Other GC2s next choice.

If you manage to make them last this time, then it'll be worth paying for better.

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

A pricier up-front investment, but may pay off long run, is the Firefly Oasis, only lead battery that will really stand up to your PSPC abuse situation, check out Maine Sail's reports on that.

But $500 per 100AH, and you will want to give them their manual "restore cycle" every month or two.

By "great value" do you mean Walmart brand?

sstuller · 04-04-2017, 01:17

Six two volt batteries connected in series will give you the AH capacity you need without any parallel connections. A single string meeting your AH requirements is considered best practice. Thanks.

NakedCity · 04-04-2017, 05:12

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

ranger58sb · 04-04-2017, 05:56

Quote:

Originally Posted by snotter

Since the 3 group 31’s were still going strong, and because all of Maine Sail’s brilliance didn’t rub off on me, and since I am also a tight wad, I built another battery box and populated it with 3 group 27 batteries that I bought from my local auto parts store and connected them in parallel with the 3 group 31’s previously bought.

Wishing to avoid another melt-down, I went to my local auto parts store and bought 3 group 31’s and 3 group 27’s and once again life was sweet. About 2 years after replacing these batteries,

I have identified at least two options open to me, both of which utilize group 27 batteries: 1) buy 6 of the cheapest so-called deep cycle batteries from an outfit that can provide 6 matched batteries (same lot # and same date code); or, 2) buy 6 matched Trojan SCS200’s, at almost twice the cost of option 1. I would take option 2 in a heartbeat IF the Trojans are significantly better than the typical so called deep-cycle battery sold at Costco or Sam’s. It would please me if I could get 4, 5, or 6 year life expectancy out of my next set of batteries.

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

Your mixed bank is maybe 550 Ah, something like that? 6x G31s would be about 600 Ah or slightly more, depending on brand and their marketing department...

Four golf cart batteries will almost fit in the same footprint as 3x G31s, so if you have the height available... maybe 6x GC2s could fit? That'd be about 660 Ah... 8x GC2 would be about 880 Ah, and might fit where you now have 6x G31s/G27s...

6x Firefly AGMs would also be about 600 Ah and might address your wet cell exposure issues under sail... and MaineSail and others have reported they seem to work well in PSOC operation... at the cost of an arm and a leg and your first-born. Still, might be worth a look if you can't manage a GC2 solution. Our oldest bank of G31 AGMs (Odyssey) are just now starting their 12th season, so if the Firefly G31s do as well, it could be almost cost effective and you'd also ease maintenance chores.

(Note: AGMs ARE lead-acid batteries.)

-Chris

john61ct · 04-04-2017, 06:48

Quote:

Originally Posted by Scot McPherson

By "great value" do you mean Walmart brand?

No I meant the GC2s I was discussing there, didn't mention Walmart, what made you think of them?

I don't think I've ever seen true deep cycling of any kind at any Big Box retail outlet other than the 6V GC2s sold at Sam's Club / Batt+ (Duracell/East Penn) and Costco (Johnson Controls, not quite as good).

**a64pilot** · 04-04-2017, 07:15

Sams Club is Walmart, I believe.
However for the $, you just can't get a better battery. They are too tall to fit in my boat though.

pcmm · 04-04-2017, 08:28

Quote:

Originally Posted by snotter

Once again, the batteries in the house bank of my Morgan 415 OI need replacing. In the 10 years or so that I have owned the boat, this will be the 3rd time I have had to replace my batteries.

My boat, when I got it, had two 4D, open lead acid batteries connected in parallel for a house bank. I had no coulomb counter aboard at that time and kept the batteries (they seemed to work) until a cell shorted out, causing a thermal runaway when I wasn’t aboard. Afterwards, upon coming aboard, I was greeted with the smell of sulfur and burnt wood. Moreover, all the positive battery wires from the dumb old Charles Marine charger were bare and red puddles of melted plastic were under the run of bare wires. Fortunately, the Charles Marine charger was a complete loss.

Because the 4D batteries weren’t deep cycle, and because they were very heavy, I went to a local auto parts store and bought 3 group 31 deep-cycle batteries to replace the 4D batteries. This worked fine and I kept this configuration until I discovered Main Sail’s brilliance and decided to improve my 3-battery bank. Maine Sail taught me that my supposedly deep cycle batteries weren’t deep-cycle at all. Also, I learned that adding a coulomb counter would help me keep my house bank above 50% SOC, extending battery life. Since the 3 group 31’s were still going strong, and because all of Maine Sail’s brilliance didn’t rub off on me, and since I am also a tight wad, I built another battery box and populated it with 3 group 27 batteries that I bought from my local auto parts store and connected them in parallel with the 3 group 31’s previously bought. I even let Main Sail convince me to buy a sterling smart battery charger. With the new setup connected and working. Life was sweet—at least for a bit.

After about 3 years I noticed that my 6-battery house bank was starting to show almost 3 continuous amps going into the batteries, even when the boat was at dock and the charger was in float mode. This was strange to me since the batteries use to only accept 0.3 amps. Being concerned, I checked the batteries and discovered a very hot cell in a group 31 battery. Wishing to avoid another melt-down, I went to my local auto parts store and bought 3 group 31’s and 3 group 27’s and once again life was sweet. About 2 years after replacing these batteries, Maine Sail taught me that Coulomb counters really suck at predicting battery SOC. I bought a Ballmar Smart Gauge battery monitor from Maine Sail and was pleased that it worked as advertised and allowed me to actually keep my batteries above 50% SOC.

Now that the battery bank is now 3 years old or older, the trusty Smart Gauge is telling me that I no longer have enough battery capacity to spend a night on anchor. However, this time I am not surprised I need new batteries--Maine Sail has taught me that open lead-acid batteries don’t like hot engine room spaces and that my batteries are orientated so that the top of the cell plates would be exposed when my Morgan is heavy under sail into the wind. Indeed, my only surprise is that my batteries lasted as long as they did.

Now why am I posting this thread? I want to use a little more intelligence this time when buying my lead. Since a lot of you skippers are smarter than me, I am soliciting your council. Here are my constraints: because I am not willing at this time to move the batteries out of the engine room, the new batteries are going to have a tough life; and, since I am not willing to reconfigure my battery boxes, the new batteries will be sub-optimally placed for sailing (the tops of the lead plates may get exposed when I sail); since my batteries are destined for a pre-mature death, I want to get the most bang for my buck. I have identified at least two options open to me, both of which utilize group 27 batteries: 1) buy 6 of the cheapest so-called deep cycle batteries from an outfit that can provide 6 matched batteries (same lot # and same date code); or, 2) buy 6 matched Trojan SCS200’s, at almost twice the cost of option 1. I would take option 2 in a heartbeat IF the Trojans are significantly better than the typical so called deep-cycle battery sold at Costco or Sam’s. It would please me if I could get 4, 5, or 6 year life expectancy out of my next set of batteries.

Thanks all for your wisdom and patience,
Ralph

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.

70AMX · 04-04-2017, 08:53

There is talk at the RV forum about the Interstate batteries at Costco now being made by Trojan.
RV.Net Open Roads Forum: Tech Issues: Are Interstate 6v Now Trojans?

CampDavid · 04-04-2017, 09:21

Before you rush off and spend money you might want to address your actual size requirements and charging system. A quality 3 stage charger will make your battery bank last much longer. Many people fail to use distilled water. For the money it is very hard to do better than US Battery Crown Battery and Trojan T105. Invest in a good charger a watering system and a proper sized battery bank. Your charger and alternator should be 25 percent of the amp hours of the battery bank . Ie 4 gc2 batteries need a 100 amp charge system to get fully charged which increases the life span.

If you look after golf carts ypu get 6 plus years from a set based on a 100, 50 percent discharges.

Sent from my SGH-I337M using Cruisers Sailing Forum mobile app

RSB333 · 04-04-2017, 10:10

Our Deka agm's lasted six years and showed no signs of wearing out when we sold the boat. A set of four 105AH batteries handled our live-aboard needs, but we kept them well charged with our little Honda 2000, solar panels and smart charger.