I don't understand batteries

[duncan_ellison]

Since I have you all assembled here .....

I've been putting off replacing the (five) 110Ah batteries on my Jeanneau 45DS mainly because of all the arguments pro and con playing out above.

I had an opportunity to buy 5 x regular 'maintenance free' batteries for a very good price, but then thought better of it as I picked one of them up and a very small amount of electrolyte escaped from the top.

For reference, my battery bank is located under the rear cabin bunk and does not feature any kind of tray or containment, it's just the regular cabinetry of the interior that holds them in.

So now, although my heart (and wallet) says just go with regular maintenance free batteries, I think I might be panicking all the time that I'm spilling acid when I'm heeled over and I should really be going with gel ($$$$$$-ouch) or AGM.

Am I overthinking this as that's what I have at the moment and it's how Jeanneau designed the boat?

Duncan

[AMCarter3]

Originally Posted by goboatingnow

AGMs are not a good fit for boats and Gel is even worse , AGMs are regularly damaged by boat charging practices and Gels are completely unsuitable in my opinion

All batteries can be “ deep discharged “ good deep discharge batteries can and are designed for high current discharges and recharges likec traction motor usage. This type of usage profile is very uncommon on a standard modern yacht.

I fully disagree with the claim that AGM batteries are not a good fit for boats. My boat is in a fleet of 57 charter boats. Nearly all of the boats in this fleet have AGM's. A few still use wetcells. And a few have leaped (happily) into Lithium batteries. The AGM boats hold up just fine for years as long as they are routinely (2-3 times per year) put through a careful deep discharge process... 1) apply a static 10-20 amp DC load; drawdown to 50% of the Ah capacity of your bank; 3) recharge from shore power (this last part is extremely important).

[ColIn Ferguson]

I have had sealed flooded lead acid batteries last for more than 10 years when kept on low amp solar maintenance charge. They are sealed and therefore dont leak or need top up maintenance.

My understanding is that these high capacity flooded batteries are a different construction from starter batteries in terms of the thickness of the plates used, and should not be used for engine cranking.
The difference in cost is such that I can't see the point of AGM or LiFepo4 systems. And they dont undergo spontaneous combustion.

With solar the days of deep discharge are pretty much gone.

[goboatingnow]

Originally Posted by ColIn Ferguson

I have had sealed flooded lead acid batteries last for more than 10 years when kept on low amp solar maintenance charge. They are sealed and therefore dont leak or need top up maintenance.

My understanding is that these high capacity flooded batteries are a different construction from starter batteries in terms of the thickness of the plates used, and should not be used for engine cranking.
The difference in cost is such that I can't see the point of AGM or LiFepo4 systems. And they dont undergo spontaneous combustion.

With solar the days of deep discharge are pretty much gone.

I agree , once you look at high end LA these days either wet or AGM , you’d be better deploying LFP tech and gaining real advantages.

Back in the shallow end of the pool, the cost of of wet VRLA makes them attractive and as you say solar these days mitigates against deep discharges.

By the way reenforced plates are there to facilitate high rate over extended time period discharges and equally high rate charges. But boats, especially with solar often don’t have such usage characteristics. Hence thinner plate VRLAs often proceed very useful service life’s at a good value point.

[Rumrace]

Love your 45 DS Duncan. I’ve the 38SO no where near your grand rear suit. Batteries were in the plywood nest but behind the washroom wall which is great.
I bought the boat with dead swollen batteries after 2 years with winters.
I’m surprised you don’t have batteries up front also. I have 2 under the bed.
I’ve never had a power issue with them. They were way too expensive and then I run out of complaints

[duncan_ellison]

Hi Rumrace, Yes, I like it too

I also have two batteries under the fwd. berth for the bow thruster. These were Red Optimas which I think were probably the original fitment, but on one of them the lead post corroded off completely. I replaced them with Varta AGM batteries which are normally used for start / stop vehicles and so far they are working fine at less than half the price.

[Rumrace]

I’ve always felt the SD’s were dolls. I’m looking at 440’s now that I’m comfortable with Sailboats. I downsized from a larger SeaRay and put the money in the bank.
I won’t hesitate to put what ever leading lithium battery made closest to my home.
I home that they come from Windsor Ontario but I’m sure in the early stages cars are priorities.
I could not understand why the bow thruster didn’t work until I found where it was. You have a sail locker my bow thrusters under the bed. I have a strange desire to feed it quarters. I had the fridge adjusted and because the previous owner passed and it sat in the cold two winters all the plumbing was replaced. Shower pump was fun and Jeanneau very helpful.
My SeaRay had 3 fridges. The 395 did an amazing job of charging up 6 200 peak wets. Every morning I needed the generator to bring them up. In a previous 370 Ray I had Gels 200amp. Second best battery I’ve had.
I put solar panels on my Bimini like a newb and burnt 3 holes. So came up with new gear to suspend 4 100watt panels from Michigan 40mm above the canvas.
I 3D print and design a whole bunch of important and silly stuff for Beneteau and Jeanneau. I’m starting to do more universal stuff for domestic boats.
One cool item in a metric water fill adaptor.
It threads into your water tank and a domestic quick release hose snaps to it. No more standing for 1/2 hour holding a cut off garden hose. It fits every European boat I’ve tried. Hanse Dufour Barvaria. It doesn’t fit C&C or Catalina or SeaRay so I’m working on a domestic one.
If you have a 3D printer or a pal with one you’re welcome to the data. My two printers are booked till mid August before I can print more. Printed 40 and they are gone. Must be printed with ASA or PC

[Rumrace]

Sorry Deck Salons

[goboatingnow]

Originally Posted by Rumrace

I’ve always felt the SD’s were dolls. I’m looking at 440’s now that I’m comfortable with Sailboats. I downsized from a larger SeaRay and put the money in the bank.

I won’t hesitate to put what ever leading lithium battery made closest to my home.

I home that they come from Windsor Ontario but I’m sure in the early stages cars are priorities.

I could not understand why the bow thruster didn’t work until I found where it was. You have a sail locker my bow thrusters under the bed. I have a strange desire to feed it quarters. I had the fridge adjusted and because the previous owner passed and it sat in the cold two winters all the plumbing was replaced. Shower pump was fun and Jeanneau very helpful.

My SeaRay had 3 fridges. The 395 did an amazing job of charging up 6 200 peak wets. Every morning I needed the generator to bring them up. In a previous 370 Ray I had Gels 200amp. Second best battery I’ve had.

I put solar panels on my Bimini like a newb and burnt 3 holes. So came up with new gear to suspend 4 100watt panels from Michigan 40mm above the canvas.

I 3D print and design a whole bunch of important and silly stuff for Beneteau and Jeanneau. I’m starting to do more universal stuff for domestic boats.

One cool item in a metric water fill adaptor.

It threads into your water tank and a domestic quick release hose snaps to it. No more standing for 1/2 hour holding a cut off garden hose. It fits every European boat I’ve tried. Hanse Dufour Barvaria. It doesn’t fit C&C or Catalina or SeaRay so I’m working on a domestic one.

If you have a 3D printer or a pal with one you’re welcome to the data. My two printers are booked till mid August before I can print more. Printed 40 and they are gone. Must be printed with ASA or PC

Hmm , i just stick the end of the hose down the boats inlet I don’t then have to hold the hose

[P3sailor]

Two years is excessive but if they were fully charged prior to storage that surely would have helped providing they were completely disconnected from the ships electrical supply.

[Mike OReilly]

Just to follow up with this, I just put my boat back on the hard for yet another Newfoundland winter. We had a good season that included 45 straight days off the dock, with much of that on extended anchor.

My batteries -- the ones that were abandoned for 33 months -- did fine through all of this. My wind and solar chargers kept them well topped up most of the time. I only had to resort to using the gas generator a couple of times after extended overcast/no-wind periods.

I do think these batteries have diminished capacity, but they are six years old now, so I'd expect that at the best of times. They seem to be functioning just fine.

So... I put them to bed the same way I always do, and I hope to get another season out of them in 2023. I'll let you know what I find in the spring.