Understanding Lead-Acid Battery Life

[john61ct]

Originally Posted by tanglewood

Oh, and you had asked about orientation. I don't know about Winston and others, but CALB wants them upright.

I stand corrected, and will need to revisit several installs. Some are 3+ years trouble-free so far, but. . .

_____
From Jack Richard @EVTV (great resource BTW)

The manufacturer advises us that the ideal mounting of the cells is vertical with the vents pointing UP.

Mounting the cells upside down is absolutely forbidden as this causes electrolytes to pool in the pressure vent, disabling it.

Horizontal mounting is somewhat more controversial. The manufacturer advises this shortens cell life, with mounting on edge preferable to mounting flat side down horizontally.

We have yet to receive a cogent explanation of why horizontal mounting would cause any decrease in battery life or capacity. But this remains the manufacturers recommendation and we pass it on.

[hellosailor]

John-
A WAG about a possible issue with horizontal mounting. The cells normally have the separator "hanging" up and down, when they are in the default vertical orientation. So any chemical formations (i.e. the dreaded dendrites that can penetrate the separator) will be forming horizontally, and as long as they don't grow long enough, they won't reach the separator, much less penetrate it.
Now, if the battery is horizontal? Any dendrites that form could simply "fall" into the separator. Or, be encouraged to grow down into it, under the pull of gravity.

Just a WAG, but gravity could easily play some subtle role.

Or the battery construction just might not be as robust in that orientation, since it is not the design default.

[john61ct]

Yes in my 20 min googling, there is a lot of variation in the construction details from one mfg to the next.

Some people do just saw their big prismatic cells open [emoji13]

That variability contributes to the confusion and disagreement.

So I guess if sideways (on edge only) is a requirement, asking the trustworthy makers' tech support becomes important. They really should mention it in their documentation, even marketing materials.

I really enjoy learning new stuff every day!

[rgleason]

John wrote:
When you say "these portables" what do you mean

The clever pelican case portables on tanglewood's website with the excellent wiring diagrams.

[rgleason]

When you say "these portables" what do you mean?
Tanglewood's excellent portable pelican case lfp. Good wiring diagrams too.

[tanglewood]

Originally Posted by rgleason

When you say "these portables" what do you mean?
Tanglewood's excellent portable pelican case lfp. Good wiring diagrams too.

Not my web site. So much be another one.

[hellosailor]

john-
Did you notice over on that EV web site, that they are selling large cells (i.e. 40A, 100A) in aluminum cases, rather than plastic?
Supposedly because the aluminum has better heat transfer the batteries will get significantly longer number of cycles, at any depth. Way more cycles.
Which sounds like "Whoa, how did an entire industry miss out on this for so long?" Or...."More filling! Tastes great!"

[john61ct]

House usage is gentler, rarely do batts get much hotter than ambient.

In an engine room that design would make matters worse.

In cold use cases, I insulate the box

[rgleason]

Originally Posted by tanglewood

Not my web site. So much be another one.

Sorry,

Entropy
https://www.entropypool.de/2015/06/0...-battery-pack/

[Kenomac]

As Pam and I make our way down the Croatian coastine with our batteries fully charged 100%, I can’t help but wonder why you don’t add 2-3 100 watt solar panels to the top of your dinghy davit system? Your davit system along with your dinghy are a pre-existing condition, so adding the solar panels won’t add any addition windage.

Your problem will be solved for relatively short money.

[Dockhead]

Originally Posted by Kenomac

As Pam and I make our way down the Croatian coastine with our batteries fully charged 100%, I can’t help but wonder why you don’t add 2-3 100 watt solar panels to the top of your dinghy davit system? Your davit system along with your dinghy are a pre-existing condition, so adding the solar panels won’t add any addition windage.

Your problem will be solved for relatively short money.

If that's addressed to me -- I've answered it before. I love solar and had a large solar installation on the last boat.


But my sailing is different from yours -- I sail sometimes thousands of miles UPWIND every season. I spent a heap of money on carbon laminate sails and stripping every bit of windage off the boat I could. I got rid of my lovely wheel-steered large dinghy, which could only be carried in davits, and acquired a folding RIB which I can stow out of the wind. I took off my davits and installed much smaller manual ones, which wouldn't accept solar panels even if I were willing to accept the windage, which I am not.



Unfortunately solar is just not possible on my boat with the kind of sailing I do.


The next boat will have solar panels built into the pilothouse roof.

[Kenomac]

Originally Posted by Dockhead

If that's addressed to me -- I've answered it before. I love solar and had a large solar installation on the last boat.


But my sailing is different from yours -- I sail sometimes thousands of miles UPWIND every season. I spent a heap of money on carbon laminate sails and stripping every bit of windage off the boat I could. I got rid of my lovely wheel-steered large dinghy, which could only be carried in davits, and acquired a folding RIB which I can stow out of the wind. I took off my davits and installed much smaller manual ones, which wouldn't accept solar panels even if I were willing to accept the windage, which I am not.



Unfortunately solar is just not possible on my boat with the kind of sailing I do.


The next boat will have solar panels built into the pilothouse roof.

We are presently sailing a 750 mile round trip over the next 10 days with our house bank at 100%. Much of it upwind.

[Dockhead]

Originally Posted by Kenomac

We are presently sailing a 750 mile round trip with our house bank at 100%. Much of it upwind.

Enjoy!


I'm stuck here on land, separated from my boat for the third week already and already itching to get back on the water. 4000 miles this summer somehow didn't get it out of my system.

[rgleason]

I found this to be an excellent beginning reference for beginners/refresh, answering many questions frequently asked or presented on this forum, but not the technical & detailed ones.

Northern Arizona Wind & Sun Deep Cycle Battery Frequently Asked Questions

John at Attainable Cruising Adventure, "The yachting press and most battery experts have told us that you should not equalize AGM batteries. Wrong—any lead-acid battery of any type will sulfate with typical liveaboard use and eventually fail if you don’t get rid of that sulfation regularly with equalization. So, if you can’t equalize a battery, it does not belong on a voyaging boat."
He also says many chargers are incorrectly programmed as they come from the factory (even 3 stage), and they should user programmed for the batteries.

John also wrote: "A lead-acid battery is fully charged when the current (amps) it will accept at its specified acceptance voltage—typically about 14.4 volts at 70F (20C)—has dropped to 1-2% of the total capacity measured in amp hours. This is the only practical way to know that a battery is charged." He continued, saying that achieving full charge every time is "totally impractical on a voyaging sailboat" and requires hours of engine time. [The lead acid "Long Tail"]

He also details the problems with all the clutter and paraphernalia above deck, when going offshore (which includes large arrays of solar panels). He does say "I guess its alright for inshore."
----

Are Deck solar panels more slippery than the deck? Can they be an effective way to use PV? Where (side decks, fore deck, cabin top)? My cabin top has no real clear area that can be used.

[HayesJJ]

I have a very similar issue with my battery. It's AGM type and served me for good 3 years I noticed that it's getting worse and worse. I was promised it will hold without problems at least 5 years