Luddite Battery Replacement

[eherlihy]

After six years and one month, it seems that my house bank, consisting of TWO Duracell Group size 31 Model # 31DCX (mfg 6/20), has finally bit the dust. Their periodic consumption of distilled water has gone up significantly, and the other day in a critical situation, they failed to start. Yesterday, I added a total of about half a GALLON of distilled water to top off all three batteries, when I usually use less than 500 ml during a season.

The situation was after spending a night at anchor in the Kickamuit River, I was trying to exit the Kickamuit under sail. While I was approaching R N "6", with the current against me, the wind died, or I was in the lee of the houses on the west bank, and the boat speed dropped to 0.4kt against a 0.5kt current.

I was fortunate to have bank 2 fully charged, so I quickly dove below deck, flipped the switch to bank 2, and got back to the helm. I started the engine, and got back on course without running aground.

Anyway, I will be looking for new Flooded Lead Acid batteries for my vessel. I'll replace the start battery while I am there, because I would like to keep them all about the same age. Right now, I am looking at 2 EverStart Group 29 Deep Cycle batteries, because I can't find Group 31 Batteries anywhere in southeastern Mass or RI.

During the season, I keep the batteries charged by a 100 Watt Solar Panel, which is then connected to a Victron Energy MPPT Controller, which is set up for Flooded Lead Acid Batteries.

If it helps, here is a schematic of the charging setup of my primary electrical system;

TLDR; I am looking for battery recommendations. I am currently planning on 2 EverStart Maxx Group 29DC batteries from Wally-world for ~$260.
Change my mind!

 

[fred1diver]

I have and can recommend 2 6v golf cart batteries, wire them in series, the ones I use are said to supply 230 amps/hours. Way more than needed, they are about 6 years old, I do have to top them
Once in a while with distilled water, but maybe once a season so far.
They are extremely heavy and do take more room, but for us it is an excellent trade off

 

[eherlihy]

I have and can recommend 2 6v golf cart batteries, wire them in series, the ones I use are said to supply 230 amps/hours. Way more than needed, they are about 6 years old, I do have to top them
Once in a while with distilled water, but maybe once a season so far.
They are extremely heavy and do take more room, but for us it is an excellent trade off

Yes, thanks for that. Unfortunately I am space limited on my boat. I could fit the Grp 31 batteries, but with about a quarter inch of space between the top of the batteries and the compartment that they occupy. Golf cart batteries will simply not fit.

 

[eherlihy]

I went to Costco today, and bought 3 Interstate Marine Deep Cycle batteries; 2 Group 31, and 1 Group 24. The total, including MA Tax, was $361.22

 

[Richard19068]

I went to Costco today, and bought 3 Interstate Marine Deep Cycle batteries; 2 Group 31, and 1 Group 24. The total, including MA Tax, was $361.22

Another 6 years!

 

[Don S/V ILLusion]

Be aware that because they are not of similar capacity, charging them becomes a bit more complicated. Ask if you need more info.

 

[eherlihy]

Be aware that because they are not of similar capacity, charging them becomes a bit more complicated. Ask if you need more info.

The two Grp 31 are Bank 1 (House) and the single Grp 24 is bank 2 (Spare). See the diagram of my charging system above for details.

 

[eherlihy]

Another 6 years!

I got 7 out of the last batteries...

 

[Don S/V ILLusion]

The two Grp 31 are Bank 1 (House) and the single Grp 24 is bank 2 (Spare). See the diagram of my charging system above for details.

I looked but hard to follow. Just wanted to pass along the suggestion which I infer you already understood.

 

[Maine Sail]

After six years and one month, it seems that my house bank, consisting of TWO Duracell Group size 31 Model # 31DCX (mfg 6/20), has finally bit the dust. Their periodic consumption of distilled water has gone up significantly, and the other day in a critical situation, they failed to start. Yesterday, I added a total of about half a GALLON of distilled water to top off all three batteries, when I usually use less than 500 ml during a season.

The situation was after spending a night at anchor in the Kickamuit River, I was trying to exit the Kickamuit under sail. While I was approaching R N "6", with the current against me, the wind died, or I was in the lee of the houses on the west bank, and the boat speed dropped to 0.4kt against a 0.5kt current.
View attachment 238668
I was fortunate to have bank 2 fully charged, so I quickly dove below deck, flipped the switch to bank 2, and got back to the helm. I started the engine, and got back on course without running aground.

Anyway, I will be looking for new Flooded Lead Acid batteries for my vessel. I'll replace the start battery while I am there, because I would like to keep them all about the same age. Right now, I am looking at 2 EverStart Group 29 Deep Cycle batteries, because I can't find Group 31 Batteries anywhere in southeastern Mass or RI.

During the season, I keep the batteries charged by a 100 Watt Solar Panel, which is then connected to a Victron Energy MPPT Controller, which is set up for Flooded Lead Acid Batteries.

If it helps, here is a schematic of the charging setup of my primary electrical system;
View attachment 238672

TLDR; I am looking for battery recommendations. I am currently planning on 2 EverStart Maxx Group 29DC batteries from Wally-world for ~$260.
Change my mind!

G-29 is a G-31 with a Wal-Mart group size. If the serial # on the batts at Walmart starts with EP they are made by East Penn. If it does not start with EP run away.

 

[eherlihy]

G-29 is a G-31 with a Wal-Mart group size. If the serial # on the batts at Walmart starts with EP they are made by East Penn. If it does not start with EP run away.

Can you shed any light on who makes Interstate Group 31 Marine Batteries?

[EDIT] NVM - Google AI tells me that they were probably made by Johnson Controls (now known as Clarios).

 

[jssailem]

Interstate is a marketing and distribution company. The exact manufacturer for any specific Group 31 marine battery can vary by model (flooded deep-cycle vs. AGM), production date, and supply agreements. It is often difficult or impossible to identify the maker from the Interstate branding alone, as the batteries are private-labeled.