Update on Battery Choices

Time for a battery update.....so what is the best battery choice for a house battery bank. (and start/gen/thruster etc, if you wish).



Hopefully this would be for the groups "average" boater, if there is one....
One with a power boat that wants a battery bank good enough to hang on the hook without a generator to run minimal things for perhaps a day or two. Reliable that will last at least 5 years or more. Best amps for the buck.


For me, I have the Lifeline AGMs and am very happy with them and do all of the above. My bank is six 6v 220amp batteries that I end up with a total of 660 amps, which gives 330 usable (50%) which will run two fridges, TV, computer, lights, make coffee, heat something in the micro and have power left over. Been using AGMs from Lifeline (Concord) for years with excellent service).



BUT, the technology is changing are there's other options....


Is it prime time for lithium? LifePO? How about the Firefly Oasis? Other thoughts?

My batteries live in the vented engine room. I have easy stand up access. I have 8 Dyno L16 commercial grade lead acid batteries for a total of 1500 amp hours or 750 usable amp hours. My last set went 10 years. Total coast of my bank is $2,000. That’s a lot of bang for the buc.

Tilt,


That is a lot of bang for the buck.... Looks like you need to water these, correct?

We went old school as well, with 8 X 6v Trojan T-105, for 900 amp hours. Being flooded lead acid, I consider about 35% of that usable (the range from 50% to 85%), although they often do top off closer to 100% full. That gives us a conservative 300 usable amp hours for $1000 or so. Longevity has not yet been tested (about a year old), but the reputation of these old school batteries is decent. Yes, I do have to water them. It is more accurate to say I have to check them. They do not seem to lose/use any water, but I put a thimble full in once I have them open.

It seems like very good bang for the buck, but it would be a step down from where you already are, Seevee.

Having converted to AGM, I am not looking back.

I'm another lead acid user. My house bank is 8 Interstate golf carts, about 1,000 ah at 12 volts, half usable. Like Tilt Rider above, I get good service life from LA, 6-8 years in my case. I see LA as cost-effective and I've resisted changing to high tech batteries primarily for that reason. Changing the cabling and battery boxes doesn't appeal to me much either.

Steve
If you have a Sam's Club near by check out their Duracell AGMs made by East Penn. I now have 2 8D AGM for house / start and will not replace w 8Ds.
Looking at putting in 4 12V AGM GP 31 for a house bank.
At 105 AH ea a pair is very close to a pair of 6V GC2s.
I have talked to east Penn and they have confirmed that with AGMs there is no deep cycle advantage between GC and GP31... plate design same w AGM. I believe that's why they report AH and CCA for their AGM line.
Not sure what $ is for Lifeline but I would guess the Duracell / EP will be less $/AH. I have had good luck w EP AGMs (current 8Ds + others) now 6 yrs old and still going strong. I store them aboard overwinter w/o charging and consistently read 12.6V - 12.7V in spring before connecting & topping off.

AZ2Loop said:

We went old school as well, with 8 X 6v Trojan T-105, for 900 amp hours. Being flooded lead acid, I consider about 35% of that usable (the range from 50% to 85%), although they often do top off closer to 100% full. That gives us a conservative 300 usable amp hours for $1000 or so. Longevity has not yet been tested (about a year old), but the reputation of these old school batteries is decent. Yes, I do have to water them. It is more accurate to say I have to check them. They do not seem to lose/use any water, but I put a thimble full in once I have them open.

It seems like very good bang for the buck, but it would be a step down from where you already are, Seevee.

Click to expand...

AZ,
You might get a better bang for the buck with the AGMs, even though they are double or more of the cost. At $300 each (price higher now, but so are Trojans) $1800 and a full 50% gives a usable 330amp hours, and zero maintenance. I'm expecting 6 or 8 years of service on these... maybe more.... The same a battery (but the aviation version) has given me 6+ years in my plane for well over 6 years each, and still working well when removed.



Now, they will require a smart regulator, so if you don't have that on your engine alternators, that will be an expense.



And, the LifePo or Oasis could be a good choice, too.... waiting for others to comment.

I have 4 6 volt T105 Trojans for house. 440 Total amp hours. I figure 150-200 usable. I use about 100 amp hours in a 24 hour period. That includes refer, coffee in the morning with inverter, a few led lights, water pump and a couple hours of music. Recharge with generator every day.

It's hard to beat cheap flooded batteries in $/AH. But it is easy to beat them in maintenance, lack of corrosion, lack of fumes, lifetime, etc. I would not spend the money on Lifeline AGMs unless your charging facilities are adequate to treat them properly, but if they are, the lifecycle costs of Lifelines will be lower in exchange for higher initial investment. LFP will be lower still, at still higher investment but the payoff is many years down the road and many do not own the boat that long.

Most batteries in boats don't die of old age, they are murdered by their owners, if you are going to do that then flooded cells are the obvious choice.

We have 8 x Interstate 6v (Costco). Elimated watering hassles with Battery Watering Technologies. Battery Watering Technologies IIRC purchased thru Hodges Marine for about $180 (24 cells).

Hi Seevee,

Battery lifecycle costing is oh, SO much complex than simple $/AH considerations. And while the simplistic answer to your question of

Is it prime time for lithium? LifePO? How about the Firefly Oasis? Other thoughts?

Click to expand...

is to simply replace yours with like kind, and be done with it, I presume by your inquiry you have some desire to upgrade your existing electrical system. And THAT's a way, WAY more complex issue than "what kind of battery should I buy?" And in my opinion, more complex an issue that can be properly addressed in an open forum such as this.

If you're interested in battery "system" upgrades (and it's truly a SYSTEM, as many posters have already alluded to), suggest you start by looking at this interesting lifecycle battery comparison tool:

Comparing marine batteries (Gel, Absorbed Glass Mat (AGM), flooded lead acid)

The data's kind of old (particularly the retail costs of the various marine batteries in Vonwentzel's database), but those are easily modified for present day costs in your local area.

And then, of course, there are a myriad of other learning tools on the WWW, such as https://www.pysystems.ca/, https://marinehowto.com/, and many others.

Regards,

Pete

Hi Tiltrider1,

Weeeellll, given the current street price, f.o.b. the loading dock of Dyno Battery in Ballard is ~$360 a pop, I'm betting that, if the original poster could fit L16's into his battery space, and if he's willing to put up with the maintenance issues associated with flooded lead acid batteries, the shipping cost and local taxes alone of 1100 lbs. of batteries to the east coast will buckle his knees.

$2000? Probably way closer to $4000, installed in St. Pt.

Good batteries, not particularly cost effective for a lot of reasons, for a lot of people.

Regards,

Pete

jungpeter said:

Hi Seevee,

Battery lifecycle costing is oh, SO much complex than simple $/AH considerations. And while the simplistic answer to your question of



is to simply replace yours with like kind, and be done with it, I presume by your inquiry you have some desire to upgrade your existing electrical system. And THAT's a way, WAY more complex issue than "what kind of battery should I buy?" And in my opinion, more complex an issue that can be properly addressed in an open forum such as this.

If you're interested in battery "system" upgrades (and it's truly a SYSTEM, as many posters have already alluded to), suggest you start by looking at this interesting lifecycle battery comparison tool:

Comparing marine batteries (Gel, Absorbed Glass Mat (AGM), flooded lead acid)

The data's kind of old (particularly the retail costs of the various marine batteries in Vonwentzel's database), but those are easily modified for present day costs in your local area.

And then, of course, there are a myriad of other learning tools on the WWW, such as https://www.pysystems.ca/, https://marinehowto.com/, and many others.

Regards,

Pete

Click to expand...

Pete,


You're right, there's a LOT to batteries, but one needs to start somewhere, and that would be with the options of different battery technology, and that's why I ask.



No, I'm not upgrading on my present boat, I'm good for at lease 6 more years or more and things will change by then. I'm shopping for a boat and from what I see, there's a likelyhood that I'll replace batteries.


And, yes, cost per amp hour is a consideration. Also is maintenance, life, reliability, install issues (usually minor, but needs to be correct) and safety.


So, where would you start if you were installing a new house bank?

Seevee said:

AZ,
You might get a better bang for the buck with the AGMs, even though they are double or more of the cost. At $300 each (price higher now, but so are Trojans) $1800 and a full 50% gives a usable 330amp hours, and zero maintenance. I'm expecting 6 or 8 years of service on these... maybe more.... The same a battery (but the aviation version) has given me 6+ years in my plane for well over 6 years each, and still working well when removed.



Now, they will require a smart regulator, so if you don't have that on your engine alternators, that will be an expense.



And, the LifePo or Oasis could be a good choice, too.... waiting for others to comment.

Click to expand...

Why? In every credible test I have seen or been involved with, properly cared for FLA 6vdc batteries such as the Trojans always outlast AGMs and they are cheaper than AGMs.

Good AGMs (not the common 12v dual purpose ones) with good care can last as long as flooded, but it's unlikely they'll last longer. To me, the advantages of AGM are in higher charge acceptance, less voltage droop under momentary large loads, no offgassing in normal use and no water checks. They're definitely more expensive over their lifetime, however.

Gel is a different story. Good gel batteries with proper care can last a very long time. But they're pricey and don't have the charge / discharge rate of an AGM.

I have posted this video and others from Pacific Yachting Systems I should be getting some kind of employee discount. For those not familiar with Jeff, he is an engineer (forget what type) who has become an established figure in Washington and BC. He has presented at both the Vancouver and Seattle Boat Shows for a number of years now. He has monthly articles in two popular mags up here on the Wet Coast.

Here is a short video talking about the three non-lithium choices which is linked below.


Here is an hour presentation given at the Seattle boat show if you want to become quite knowledgeable about batteries. For example, if you go lithium you really need to go a "lithium system." If you just plunk in lithium batteries, you will probably burn out your alternator, listen and you will understand why:

Hi Seevee,

In answer to your question (presumably on a new-to-you boat):

So, where would you start if you were installing a new house bank

Click to expand...

I'd run the thing as-bought for a year, to truly understand what you've got, and formulate your next battery-related strategy. By then, you will probably have dealt with outstanding battery issues, maybe had to be towed in caused by a non-start, maybe replaced like-kind on a semi-urgent basis to save a cruise, decided just how much $$ you want to throw at an upgrade/revision/rework, how long you'll probably keep the new boat, how you're actually using it, and all the other considerations that go into "...installing a new house bank."

And again, WAY more difficult a discussion than can be productively had on on open forum. You would be well served by starting this discussion with a local professional marine electrician, and going from there.

And my answer holds, if you're looking at a rework of your EXISTING boat.

Sorry to be evasive, but it's a TOUGH conversation.

Regards,

Pete

jungpeter said:

Hi Seevee,

In answer to your question (presumably on a new-to-you boat):



I'd run the thing as-bought for a year, to truly understand what you've got, and formulate your next battery-related strategy. By then, you will probably have dealt with outstanding battery issues, maybe had to be towed in caused by a non-start, maybe replaced like-kind on a semi-urgent basis to save a cruise, decided just how much $$ you want to throw at an upgrade/revision/rework, how long you'll probably keep the new boat, how you're actually using it, and all the other considerations that go into "...installing a new house bank."

And again, WAY more difficult a discussion than can be productively had on on open forum. You would be well served by starting this discussion with a local professional marine electrician, and going from there.

And my answer holds, if you're looking at a rework of your EXISTING boat.

Sorry to be evasive, but it's a TOUGH conversation.

Regards,

Pete

Click to expand...

Pete,


Again, you're absolutely right. My current boat's electrical and battery system is perfect for my operation and will most likely do nothing. Perhaps add solar, but a different subject. I have my system schematics, limitations, programmed chargers, etc., all nailed down. So, my present boat is not an issue. The batteries and electrical system just doesn't fail (other than operator error ).





It's a new boat that I might purchase. I realize there's a lot into designing a system. However, once one knows what power is needed and what power choices make sense, it's just a matter of putting it all together to make it work.



BUT, I'd like to find out what's new, what others have done than works and just get some ideas.


If I were doing a new system tomorrow, it would be pretty close to what I currently have. But, wondering if I should be thinking about lithium or Oasis, as they are becoming popular. Don't know enough yet, but trying to get some ideas as to what will work and what will not.


I might respectfully disagree.... it's not complicated. There's really only three battery technologies that are worth considering for me: AGM, Lithium or Oasis gel.


Once one decides on the capacity needed, and how much use, they can fit a battery bank to match. That's probably step one.


After that, it's pretty simple. Be sure charging is good enough in both capacity and regulation, install is up to snuff, and it's basically done. Optional inverters and generators can be part of the equation, and I've have both.


I definitely would NOT run a boat for a year with unknown or old batteries, OR with inadequate capacity or any questionable equipment. Nor would I do the same with old electronics. BTDT and there's a strong argument to get the boat the way you want asap and enjoy it. There will be enough maintenance in the future without upgrades.



I philosophy is not to make a project out of this, but to make a decision and have it done in a few weeks.

I replaced my 10 year old bank of FLA L16’s with another of the same thing.

I have four Crown L16 batteries totaling 840AH

Yes I have to water them, no big deal, that takes 10 minutes a couple times a year with the turkey baster.

On my 4788 Bayliner i have stand up room around the batteries which are in the lazarette.

Every 6 months I add add tap water. I did mention that battery access was easy. Street price on commercial grade L16’s is $360 but, if you are buying 8 at a time you should be able to get them for $325. 8x325=2600 not 4000.

Battery corrosion is usually caused by installing the vent caps improperly. Vent caps are designed to aim venting away from the posts. Most people never pay attention to the cap and inadvertently aim the venting right at the post wich creates all that nasty goo.

While lead acid batteries give you the most bang for the buc they certainly are not always the best choice given the application. I am not willing to use lead acid batteries that are stored Or vented to a living space. I am also not willing to crawl to a battery to check its water level.

tiltrider1 said:

While lead acid batteries give you the most bang for the buc they certainly are not always the best choice given the application.

Click to expand...

I no longer believe this to be true for my boating.

When I replaced my house bank I went with L15 AGMs. I found a great buy on them and ended up with a 780 Ah battery bank. My choice was partially made based on the availability of batteries at a good price.


If there was easier access to the batteries, I likely would have gone with FLA. I also do like the increased charge acceptance of the AGM over the wet cells. It cuts down on genset runtime.

For what it's worth, I just installed 2 Northstar 8D AGM Dual purpose batteries for the house...they came highly recommend..220 AH each .

Just made the switch/upgrade from 1 Duracell 8D maintenance free (DOA after 3 years) to 2 Odyssey PC 1800 AGM . . . Fits same footprint and moves me to 428 ah (20 hours) parallel connection . . . so far so good.

Seevee said:

No, I'm not upgrading on my present boat, I'm good for at lease 6 more years or more and things will change by then. I'm shopping for a boat and from what I see, there's a likelyhood that I'll replace batteries.

So, where would you start if you were installing a new house bank?

Click to expand...

It might depend much more heavily on the space available (including height) and various layout possibilities in that next boat. Might be the best solution could be G31s, or GC2s, or L16s, etc.... and maybe you won't be able to compare perfectly without knowing those dimensions.

And then there's that whole charger thing, the rest of the DC system, etc...

We're shopping, too, and I'm considering, the same issues, expecting I won't know until I can see the spaces, evaluate the rest of the system, etc.

-Chris

JimW said:

Just made the switch/upgrade from 1 Duracell 8D maintenance free (DOA after 3 years) to 2 Odyssey PC 1800 AGM . . . Fits same footprint and moves me to 428 ah (20 hours) parallel connection . . . so far so good.

Click to expand...

Didn't realize two PC1800s would fit in the same horizontal footprint as a single 8D. Useful comment, thanks.

-Chris

I'm on year 5 with my 8 Trojan T-105s, 6 volt, 900 AH bank. They show no signs of age so far.

As mentioned earlier, most battery banks don't die, they are killed by their owner. Nice to know that for about a boat unit, I can replace the battery bank.

Ted

ranger42c said:

It might depend much more heavily on the space available (including height) and various layout possibilities in that next boat. Might be the best solution could be G31s, or GC2s, or L16s, etc.... and maybe you won't be able to compare perfectly without knowing those dimensions.

And then there's that whole charger thing, the rest of the DC system, etc...

We're shopping, too, and I'm considering, the same issues, expecting I won't know until I can see the spaces, evaluate the rest of the system, etc.

-Chris

Click to expand...

Chris,


Yes, space is a big deal, but there are solutions and in tight areas the lithium does pretty well.


Also, true about the charger (and the alternator(s))... need at least enough to charge 25% of the bank capacity. And solar could be a nice option, too.


I sure like the lithium, regardless of the price as I suspect my next boat will be my second to last boat, so will have for several years. My biggest worry with them is safety, but believe it's getting better. Hope to hear from some users. Seems like both the Lifeline AGMs and Firefly Oasis and pretty reasonable choices.

Great thread. Looking at moving from sail to power. Sailboat had 550W solar/inverter/500AH of FLA, and was looking to move to Li. No generator, but was a cat so had dual 80A hitachi alts, and I could put in quite a bit for the usual 1-2 hr a day of motoring.

Now looking at say a Bene Swift 44. Shocked to find it only has 280Ah standard for the house, very difficult to put solar on, only a 25A charger, AND only has 2 80A alts.

If you have 2 300hp engines, why not have larger smart alts, or even smart reg/alts, and why not more AH in the house? Is this because you have to take care of the start and thruster batteries?

I would think with power boats, Li would be a no brainer in the sense that it can take as much charge as you can put in. With my 2 30hp yanmars, I was still thinking of LI as I could put in 160A if I went to a smart system, but that starts loading the engines. If I have 2 or 300 hp, heck, why not crank in the Amps from them. And why just a 25A charger? That takes forever if you have generator, but maybe everyone just runs their generator the whole night all the time?

The boat I am looking at, I would see if I could add another 150Ah battery, change the charger to a charger inverter, possibly put flex solar on the soft bimini, and get a smart alt/regulator?

Or am I missing something here?