AGM or Wet Cell

[ranger58sb]

Originally Posted by Higgo

I can see the common thread of the cost benefits and durability of the FLA's, however the maintenance free benefits of AGM can't be ignored.

The batteries will be located in the underneath the saloon area seating

In relation to recharging we do have 4 x 140watt and 2 x 85watt solar panels. Would these solar panels supply enough power to regularly recharge the AGM's to 100% SoC. Our aim is to use the gen set as little as possible.

FWIW, I think batteries within living spaces would lean me even more toward AGM (or gel)... especially since you have solar to augment charging if you go with AGMs. Don't think the solar would completely replace the genset/charger, though, assuming you use DC a bit... but I'm not well versed on the various solar products around, so others can respond to that better.

Be aware, as with FLAs, there are AGMs and then there are AGMs. I've had good luck with the ones we've used, but I don't know that those results would be universal. Nor have I compared $$/amp-hour and lab-predicted cycles across many brands.

-Chris

[john61ct]

Lifeline, Northstar, Odyssey are good

and now Firefly for chronic PSOC

[a64pilot]

I have 1KW Solar charging a 660 Ah bank of AGMs and cannot get to 100% SOC in south Fl in summer, so for sure the rest of the year it's not going to be possible as there are less Solar hours.
My take is forget AGM unless you buy into regular extended generator runs as in maybe twice weekly or are often plugged into shorepower.

If I could have fit them, I would have gone the Costco / Sams club 6V golf cart battery and fitted them with the self watering caps.
I went with Lifelines which are a good battery and if I care for them I feel they will live longer than GC batteries, but they likely cost four times as much and will not live four times as long I don't think.
You just cannot beat the Sams club GC batteries on a cost basis

Gels interest me greatly as my understanding is if they are treated right, they are among the most long lived of any lead acid bank.
However at the time I had an in with Lifeline though their aviation battery sales guys and I got a real good deal. Still wonder if I shouldn't have gone the gel route

[Benjmin]

Sailboat Tech – Lithium Batteries & Why We Chose Them

[ranger58sb]

Originally Posted by a64pilot

I have 1KW Solar charging a 660 Ah bank of AGMs and cannot get to 100% SOC in south Fl in summer, so for sure the rest of the year it's not going to be possible as there are less Solar hours.

Gels interest me greatly as my understanding is if they are treated right, they are among the most long lived of any lead acid bank.

Is that with ONLY solar on a daily basis? No genset/charger every day? Or at least seldom?

I looked at gels as we were starting our transition away from FLAs back in 2005... but our path forward included using our original multi-bank charger... which would only support FLAs and AGMs on one charge profile setting... and our plan also started with only a single bank replacement (the other two remaining FLA for a while). Couldn't mix 'n' match FLAs and gels, so...

AGMs got the nod.

-Chris

[john61ct]

Originally Posted by a64pilot

I have 1KW Solar charging a 660 Ah bank of AGMs and cannot get to 100% SOC in south Fl in summer, so for sure the rest of the year it's not going to be possible as there are less Solar hours.
My take is forget AGM unless

Assuming nothing is faulty, this problem is simply the solar input not keeping up with your usage, nothing to do with the bank chemistry.

Originally Posted by a64pilot

regular extended generator runs as in maybe twice weekly

Even just an hour each morning may do the trick, key is a high CAR bank, which your Lifelines should be.

Just getting to 100% couple times a week will still murder the bank early. Strive for every cycle, then missing a few per month is NBD.

Originally Posted by a64pilot

If I could have fit them, I would have gone the Costco / Sams club 6V golf cart battery and fitted them with the self watering caps.

I went with Lifelines which are a good battery and if I care for them I feel they will live longer than GC batteries, but they likely cost four times as much and will not live four times as long I don't think.

You just cannot beat the Sams club GC batteries on a cost basis

Yes if you can't avoid PSOC abuse then either go Firefly Oasis or even LFP, or go cheap.

Properly cared for, the Lifelines are worth the extra money, but not otherwise.

[sailorboy1]

Originally Posted by a64pilot

I have 1KW Solar charging a 660 Ah bank of AGMs and cannot get to 100% SOC in south Fl in summer, so for sure the rest of the year it's not going to be possible as there are less Solar hours.

Well then you have something wrong and people definitely should not follow your advise!!!!!!!!

[a64pilot]

All I will respond with is you people who believe your banks are charged by noon every day cause your charger trips into float then, your not

OK so maybe on sunny days in June and July you actually do get to 100%, what about cloudy rainy days and the rest of the year?

Don't believe me, go see what Maine Sail says about cruising and getting your bank fully charged on Solar alone.

It is not the size of your Solar array, it's simply the number of hours per day on average of useable Solar, there isn't enough time.

So yes, your going to have to run your generator for at least an hour every morning to get the bank through bulk and a big chunk of absorption , and then let the Solar dribble the rest in over hours.

So then your the guy in the anchorage that starts the generator very early in the morning.

If you don't want to be that guy, then buy an inexpensive, but good quality flooded bank and cycle it between say 60% and 90% something charge wise and replace it in three years or so and don't worry about it. You'll likely still spend less money than the guy with the expensive AGM bank

[sailorboy1]

And I will respond that people with 300+ amp-hours/day of solar charging capacity who say it isn't enough to charge their batteries should not be giving advise as to the needs of the average cruiser. Either you are an incredible power user or you have a problem.

[Sailmonkey]

Originally Posted by sailorboy1

And I will respond that people with 300+ amp-hours/day of solar charging capacity who say it isn't enough to charge their batteries should not be giving advise as to the needs of the average cruiser. Either you are an incredible power user or you have a problem.

I think A64 has stated several times in the past that he is an incredible consumer of amp soup!

[Mithril Bham]

If switching to AGM make sure regulator is correct.

[a64pilot]

Originally Posted by sailorboy1

And I will respond that people with 300+ amp-hours/day of solar charging capacity who say it isn't enough to charge their batteries should not be giving advise as to the needs of the average cruiser. Either you are an incredible power user or you have a problem.

It's not the possible 300 AH of available charging, it's the acceptance rate of the bank and the time it takes in hours to be full. It wouldn't matter if I had a Megawatt of Solar, unless you can increase the number of Solar hours, your not getting truly 100% charged, more like 95%. That last 5% will take longer in hours than the first 30% did. I and everyone with a big enough charger can go from 50 to 85 in a hurry, but 95 to 100 takes a long time for a lead acid bank.
When my bank is down low and I crank the generator I can throw 185 amps at it, but it will only take that for 20 min, then the acceptance rate starts coming down, the closer to full, the slower it goes in.

You may pull it off for a month maybe two in Summer, but again, what about say from Sept to May? Assuming we are not on the equator and are in the Northern Hemisphere, those months your going to definitely need something to go along with that Solar or you will prematurely kill an AGM bank, maybe not Firefly, but a Lifeline you certainly will.

It's not the end of life as we know it, just your going to have to have a Honda or something to help, it's just cannot be done on Solar alone, and wind is fickle where I have been, hard to count on it, or we would sail everywhere.

[a64pilot]

Originally Posted by Sailmonkey

I think A64 has stated several times in the past that he is an incredible consumer of amp soup!

We are. What I am doing is the better half is not attune to this technical stuff at all, and I am trying to make this change as easy on her as I can. She doesn't like at all me being the water and power Nazi, so I'm not going to try to make her change her habits if I can help it, forever she has always let the water run and rinse off the dishes, which if I were jugging it would have me having fits as that stuff is heavy, so I will be installing a watermaker soon.

My goal was unlimited water and power, now by unlimited I really mean not having to ration it and chase around after her turning off lights etc. Plus excess power and water is luxurious, I like to run the ice machine when it's hot etc.

She will understand on her own by talking to others etc and our consumption will come down, and then hopefully we will have an excess.

[sailorboy1]

Originally Posted by a64pilot

It's not the possible 300 AH of available charging, it's the acceptance rate of the bank and the time it takes in hours to be full. It wouldn't matter if I had a Megawatt of Solar, unless you can increase the number of Solar hours, your not getting truly 100% charged, more like 95%. That last 5% will take longer in hours than the first 30% did. I and everyone with a big enough charger can go from 50 to 85 in a hurry, but 95 to 100 takes a long time for a lead acid bank.
When my bank is down low and I crank the generator I can throw 185 amps at it, but it will only take that for 20 min, then the acceptance rate starts coming down, the closer to full, the slower it goes in.

You may pull it off for a month maybe two in Summer, but again, what about say from Sept to May? Assuming we are not on the equator and are in the Northern Hemisphere, those months your going to definitely need something to go along with that Solar or you will prematurely kill an AGM bank, maybe not Firefly, but a Lifeline you certainly will.

It's not the end of life as we know it, just your going to have to have a Honda or something to help, it's just cannot be done on Solar alone, and wind is fickle where I have been, hard to count on it, or we would sail everywhere.

I'm not going to argue the fine points. The bottom line if your 1000w of solar can not get your battery charged it has an issue. I know what fully charged is and have been doing this longer than you have been repeating crap you read on the internet.

[Kenomac]

64pilot and sailorboy,

I see a Spectra watermaker in your future. We have two which produce 34 gallons per hour. Fresh water is never an issue, and they're so quiet.... we sometimes forget they're running.