Batteries

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I have a pair of dual purpose (start/house), it`s how the boat was set up by IG,seems to work ok. Yuasa/Century brand wet unsealed lead acid Marine 8Ds. They are fed by alternators, solar, and occasionally the charger. One is 2 yrs, the other 3.
Both seem to be performing well, but solar charging can cover things up. The solar charger is 4 stage, incl a monthly equalization, after which I definitely need to add water. The older one looks murky inside, dirty and oily is the best I can do. The younger is clear inside. I have fished out a loose plastic strip from one, not sure which, I assume part of a separator.
Apart from approaching replacement, before which I`ll do a hydrometer test:

1. Do I really need the equalization phase on, if the batteries are being regularly kept well charged? I believe it "pulses/vibrates" the plates.
2. Because the batteries use water quite regularly, commonly reported with solar charging, and especially equalization, I`m hesitant to replace with sealed versions, but would like to if I can. Should I be concerned, if I do it, should equalization stay off?
 
Should I be concerned, if I do it, should equalization stay off?
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Most of the sealed batts can not handle an overcharge of any type ,

however the MFG should have specific charging info on his site.
 
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https://www.flow-rite.com/battery-watering/marine-rv/pro-fill-rv

In my boat my AGMs seem to go on forever. In my work truck (which gets way more use :( ) I have too many operator errors of people letting the bank discharge too much too often.

Just recently changed to golf cart setup. 3 pairs of 6 volt. I always resisted this do the issue of filling. My B-I-L used to maintain a fleet of 110 golf carts and told me about these. All the cables make getting to caps a real PIA. But now I don't even have to open the lid. :)
 
"Should I be concerned, if I do it, should equalization stay off? __________________"

Most of the sealed batts can not handle an overcharge of any type ,

however the MFG should have specific charging info on his site.
I see that. If the equalization process requires unsealed battery re-watering after, a sealed battery would take a hammering from the significantly raised equalization charging voltage.
Following on from there. My solar panels seem keep the batteries fully charged. If undercharging, especially if chronic, causes sulfation, it follows I don`t need the equalization function on, sealed or unsealed, as fully charged they should not sulphate. Thoughts?
Edit: I checked the Manual(when all else fails...) for my PV Controllers. Equalization must not be used with sealed batteries. That leaves me deciding whether to keep it on for my unsealed ones. The "Absorb" mode provides some pulsing so I think I`ll turn it off.
 
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My solar panels seem keep the batteries fully charged.

Fully charged is just a specific gravity reading , or a specified voltage after a rest - no use- period.

HOW you get to fully charged , and how you float the system will be a large factor in batt life.

We set our solar to 13.4 , but with no loads that keeps the batt at 12.8 overnight all summer and uses very little water.
 
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We set our solar to 13.4 , but with no loads that keeps the batt at 12.8 overnight all summer and uses very little water.
FF, is that with no equalization?
What has been your battery life experience with solar support?
 
What has been your battery life experience with solar support? __________________

Our use and situation is very unique. With a propane fridge the electric demands are below minor.

At night an LED anchor light and power for a small radio.

We have only 2 truck 8D , there are built as compromise batts , big enough to start a diesel, thick enough plates to handle being used as house batts .NO really deep cycling even with a month on the hook..

There is no AC electric on board tho a 1500W chop chop inverter will operate the microwave or other appliances,phone batt chargers,computer whatever .

Our our cruising style is the hook , after the anchor is in the engine is secured and ONE batt is selected for house service.
In the AM the single batt is used to start the 6-71 and remains connected till about lunch time , wehere the second batt is joined so it can be charged.

In the evening, the second batt would work the house , and the game is repeated.

We get 6-8 years out of std 8D (about $150 each ) from the local DD dealer.

When the boat is not in use the batts only see the charge from solar,(6 months all summer) underway the imbecile single wire truck alt does not need to be replaced with a 3 v reg step, as the charge required is minor , and the charge time long.

This works for US ! , but I could not recommend it for most cruisers.
 
Some similarities here FF.
I bought the boat in 2010. It had/needs dual purpose type 8Ds, both 5yrs old, no solar, and not looked after. I replaced one 8D, saved one for a year, the genset battery for 2.5 yrs, using a desulphating agent(snake oil?), and adding solar of 90w per main battery, and 25w for genset batt. The 8Ds seem to be doing ok, I`m not sure monthly equalizing was helping, it`s off for now, and I`m suspicious about the separators condition. I`ll get new ones if I have to, but fitting 54kg batts is a PIA. So what life I will get is unclear. I replaced the genset 150ah start batt with a sealed tractor/boat one, I may get the 8D/200ah version of it for the mains if I replace, but not yet, I was hoping for 5 years.
We have a eutectic fridge & freezer. Cruising, that keeps fridges off the batteries, I run the genset early and late for the eutectics, and can charge batts, as needed, same time. For single overnights the batts are up to the job of running a 12v fridge, especially if the day was sunny and fed the panels well. Our stove is propane/LPG, we have an electric frypan/roaster, electric kettle, small espresso coffee machine all needing 240v,via the genset, and a small inverter for TV (65w), and other small things.
It`s interesting how people work out their own needs in the context of their own boat. There is usually a way of making things work. I envy your 6-8 years of battery life, I think it`s possible for us, my 8Ds need watching for now, I don`t think the equalizing has been good for them. I`m sure solar is the key to long life, packing in that last 20% they otherwise don`t get, we are on a mooring, not a marina, quite common here.
 
At an unpowered dock or floating to the ball, NO power is the same.

>electric frypan/roaster, electric kettle, small espresso coffee machine all needing 240v,via the genset, <

The std propane range handles these chores , and as noted a big expresso pot is fastest at creating AM coffee.

WE no longer have a battery TV as all the mode of transmission has changed , however when we start North again , TV is the easiest weather report , who cares what the blow dry babble is , they do show the weather map, what counts.

Switch to a propane reefer and months of no noisemaker await your pleasure.
 
Just to add, AGM sealed batteries are quite tolerant to high charge rates that could mimic a desulphation stage. In fact, they need it. I did significant research before buying AGMs and the consensus with the manufacturer was that my 80 amp charger may be too small. The AGMs desulphate during the recharge stage and if the recharge is not fast and strong enough then desulphation does not take place or it is at least retarded. So while it my not be the right thing to do to subject them to a desuphation stage of an older battery charger, they do need(rely on) a hard and heavy recharge stage for them to be desulphated.
 
Charge RATE and charge VOLTAGE are not the same.

Over voltage is the hassle for sealed batts.
 
Charge RATE and charge VOLTAGE are not the same.

Over voltage is the hassle for sealed batts.

Roger that FF. They like a lotta amps...not volts!!
 
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