Lead acids dying. What to replace with?

[Canibul]

People on this forum told me that I should expect some battery issues after lightning fried just about all the 12 volt systems on board. Two years later, they're failing. 105 AH lead acids.

So, I need to replace them. What with? Anyone know of any clear winners in the battery replacement game? We can probably buy more deep cycle lead acid batteries locally at a huge cost, or could import what we want knowing it will take a week or two to get here.

Is there any way a new Outback MPPT could fry batteries through a stupid setting on my part? I'd hate to buy four new batteries and then find out the solar sytems are cooking them away.

[djmarchand]

Well, the best bang for your buck is 6V golf cart batteries. You know for sure that these are thick plate deep cycle batteries. Some, maybe most so called deep cycle 12V batteries are just labeled that way and are really starting batteries.

The next best option are AGMs. There is no real difference between starting and deep cycle batteries for AGMs. And the ability to charge fast(with fewer losses, discharge deeper without harm and possible longer life makes them a close second to golf carts.

If you set your Outback to the correct battery type it should be fine.

David

[Canibul]

I think I'm a little confused. I just looked up "6 volt golf cart battery" and they seem to be running a couple hundred bucks apiece, and I would need twice as many to replace four 12 volt lead acid batteries, correct? You do have to put two in series for each lead acid you replace, I think?

[azsailor12]

Yes, two in series to replace 1 12V. They are more expensive, but have more Ahr capacity and last much longer.

[DeepFrz]

Take a read through Maine Sail's articles, if you haven't already done so. They will help you set up your new bank. Lots of discussion on the forum about FLA vs AGM. Personally I would install FLA golf cart batteries with the water miser caps. Or LiFePo4. Certainly some great articles on his web site to help you with your solar questions as well.
Marine How To - Compass Marine - Boat Repair Free Information

[Canibul]

Well, my confusion grows. I have the tag off one of the batteries that came with the boat, and it lists AH, or amp hours, as 105. I just went through the specs on the Marine deep cycle batteries on the NAPA site ( we do have a NAPA store here, at about 200-300% US list prices) and they don't show an AH spec at all.

I looked through the list of articles on the Maine Sail site but didn't see anything pertaining to this specific question. Not that many battery articles, unless I am missing them somehow. I saw one on preventing meltdowns with better connections, and another one on tilting flooded batteries, neither of which is an issue for me.

[colemj]

Originally Posted by Canibul

I think I'm a little confused. I just looked up "6 volt golf cart battery" and they seem to be running a couple hundred bucks apiece, and I would need twice as many to replace four 12 volt lead acid batteries, correct? You do have to put two in series for each lead acid you replace, I think?

Yes, they are 6V and you need two of them for a single 12V battery bank. However, they typically have twice the capacity of a single 12V battery, so two of them together gives you similar capacity as 2 12v batteries.

So in practice, you maintain the bank capacity using the same number of 6V or 12V batteries.

Cost is various depending on brand, etc. $200 is excessive for most - our Trojan t-105's cost $125 each. Walmart and Costco sell a close equivalent for ~$85 each. Twelve volt batteries of similar capacity to 2 6V batteries generally cost the same as 2 6V batteries.

I disagree that AGM's have any place on most cruising boats - you will be wasting money, not getting any of their potential benefits and having shorter lifespans.

It is possible your Outback is cooking them, but that would require such a bonehead setup on your part that it would be obvious to you. We suffered a lightning strike which also shortened our battery lifespans. I think this is the most likely cause of yours also. How old was your bank? If more than 3yrs, it is probably just getting time for new ones anyway.

Mark

[a64pilot]

I've seen labeling for what I believe is the same battery from 100 to 125 amp hours at the 20 hour rate.
I believe the marketing dept has gotten into labeling some batteries

[sparrowhawk1]

I'd go for the 6 volt golf batteries specifically Trojans. And yes it takes two to make a 12 volt battery but you don't need twice the batteries. If you have 4 12 volt batteries get 4 6 volt. Also did you try equalizing them? I've had batteries that weren't holding a charge very well come back after equalizing. And of course there's the liFePO4 battery. several threads with thousands of posts on that subject

[skipmac]

Originally Posted by DeepFrz

Take a read through Maine Sail's articles, if you haven't already done so. They will help you set up your new bank. Lots of discussion on the forum about FLA vs AGM. Personally I would install FLA golf cart batteries with the water miser caps. Or LiFePo4. Certainly some great articles on his web site to help you with your solar questions as well.
Marine How To - Compass Marine - Boat Repair Free Information

Exactly my thinking on batteries at this point. If you feel up to the big up front cost and a higher level of knowledge and attention to maintain LiFePO then that is the way to go.

Otherwise, 6V golf cart batteries. AGM theoretically offer some advantages for faster charging and lower safe discharge levels but do not do well if not frequently recharged to max. Also much more expensive.

I got my 6V golf cart batteries locally for about $90 each. If you research Maine Sail's articles and posts you will find that you can get the same batteries branded or rebranded and sold as "marine" for a fraction of the cost from places like Sam's Club, Costco or just wholesale battery suppliers.

[Canibul]

I really didn't mess around with the Outback. I read that it was set up for flooded batteries and didn't change anything on it.

These "Barracuda" brand ( sold only in Florida, I find out) batteries were about two years old when we bought the boat two years ago, making them right at four years old now, with a major lightning strike two years ago. Two of the four have shorted as of yesterday. We were not running the boat, just sitting at the dock and I noticed the Victron was showing some funny numbers, like 10.2 volts. Ah oh. So I clicked it to the amps in and out page and saw that the MPPT/PWM/Wind combination was pumping 7 amps into something. Went down into engine room, saw same voltages ( around9.5-10) on the Outback MPPT. Also getting Battery Too Hot error message on Outback. I disconnected battery and it's dead. Still reading around 10 volts on the remaining two, so I guess they're shot, too.

I've got the Outback, a PWM, a wind generator, and the IOTA 55 amp charger all connected to a common charging bus, which is connected to the battery bank. We rarelyr use the IOTA any more. ALso have two new Hitachi 80 amp alternators.

I'm am looking for the simplest, easiest no-brainer approach to battery bank installation and maintainenance without needing to study engineering or calculus. I'd rather just buy more batteries than worry about getting every microvolt possible from less batteries, for example. It's absolutely not a problem to keep batteries charged up here, I worry that we're putting too much into them sometimes. Solar, we got.

There are no Sams, Costco, Sears, etc. here. None. We have one NAPA store that sells batteries. I see that they do show 6 volt golf cart batteries on their web site. So I might have a chance at finding some. I have room for plenty.

[colemj]

Four years on small, off-brand batteries is about as good as it gets. I don't think lightning or the Outback or anything else is/was a problem. It is just time.

The simplest, easiest, most forgiving bank will be decent deep-cycle flooded batteries. Six or 12V, but it will be easier to get that "decentness" with 6V golf cart batteries. All of the 6V you will find are decent, but there is a lot of crap 12V batteries out there.

Are there any golf carts running around your area? If so, maybe see where they get batteries, or even get together for a group buy?

Mark

[Cotemar]

Maintenance Free Calcium battery
Group 31 with 130 amp hours # DC 31 $120 usd
13L x 6-3/4W x 9-1/2H inch about 70 lbs

Have been using these for 6 years, no worries and no re-filling

[sparrowhawk1]

Originally Posted by Cotemar

Maintenance Free Calcium battery
Group 31 with 130 amp hours # DC 31 $120 usd
13L x 6-3/4W x 9-1/2H inch about 70 lbs

Have been using these for 6 years, no worries and no re-filling

What voltage do you charge them at

[Cotemar]

Originally Posted by sparrowhawk1

What voltage do you charge them at

My Solar Panel controller is a Blues Sky Solar Boost 50 and its switch settings are:

Boost = 14.6 V & float 13.8 Volts