Battery Question - What is best

[norbert]

believe it or not, my 97 26x still runs on the original cheapo wet cell marine starter battery. engined (yamaha 50hp 4stroke) starts crabks without problems. each spring i charge it and expect it to be dead... but it works as new!

concerning kevin's initial question: i would connect the batteries via a west marine combiner. i have one bewteen starter and house batteries and it works very well.

[Paul S]

believe it or not, my 97 26x still runs on the original cheapo wet cell marine starter battery. engined (yamaha 50hp 4stroke) starts crabks without problems. each spring i charge it and expect it to be dead... but it works as new!

concerning kevin's initial question: i would connect the batteries via a west marine combiner. i have one bewteen starter and house batteries and it works very well.

I installed a Battery Distribution Cluster (same idea, but with switches) from WM (5369509) which is 3 switches and a combiner in one unit. Works pretty good. Small, easy to use, takes the guesswork out of charging. It is nice because you never have to touch the switches in daily use. No way you can flatten your starting battery, unless you switch the parallel switch.



Paul

[Duane Dunn, Allegro]

That is one of the great new switch banks west marine has for the 3 on off switch method they recommend. No thought needed in operating it like the big red 1/2/both switch which has to be set on both for charging each time you run the motor and then back on 1 or 2 for house use.

There is one disadvantage to this however. Since starting our dinky outboards really is light duty, the battery that is the house battery is the one that gets the real workout day after day and should be the one you expect to die first. With the 1/2/Both switch you can alternate which battery you are using as the house daily and get more even wear on the batteries.

Or as I have done, you can skip it all, hook them in parallel and get less over all wear on the whole system. I'm not advocating adding extra un-needed capacity to get shallower discharges from your house side. I'm advocating tapping in to the extra capacity you have sitting there in your boat going un-used in your starting side if you have a 2 bank system. You get a far simpler wiring system, less complexity, and more life due to shallower discharges with a single parallel bank of the two batteries you already own. That sweet little switch cluster shown above goes for $150. The two other similar one in west catalog go for $160 and $170 and they don't even include the combiner. I say put that money into a good Amp hour meter like the Link 10 for $200 connected to a single parallel bank and you will be money ahead in the long run. No not the 66 year long run, but the next 5+ years you are out there. Taking 50% out of a single battery daily will shorten it's life, alternating taking 50% out of one then the other is better, but taking 25% out of both together will give you more cycles, more years, in the real near term.

I have 2 group 24 dual purpose batteries 65ah each and cheap at only $69. Ones a diehard that came with the boat, who knows how old, and the other is a west marine that I added when I bought it. Both are now at least 5 years old now and still going very strong. I'm going to add a new same battery to the bank this year. Sure it would be great to have the luxury to replace all the batteries in a matched set every so often, but that's not reality. I guess I'll find out if there are any true problems putting new with old. I expect the new one may bear a bit much of the load for a while, but my load is really small to begin with so I'm not to concerned.

I have checked each of the 4 nights we have been out so far this year and from when we park the boat until the next morning our usage has been less the 8 amp hours every night, usually closer to 6ah. This is with lights (left on by 3 boys), water pump, radio, DVD player, inverter charging gameboys, etc.

There are three things that will extend your battery life. One, limiting the depth of your discharge during each cycle. Two, using a good 3 stage charger (this is why car batteries die a early death, they don't get properly charged to maximize their life). And three, periodically doing a equalizing charge cycle on the battery to dissolve the crystals of lead sulfate that have collected on the battery plates (note you don't do this to gel batteries). For most deep cycle batteries their death comes when the build up of lead sulfate reaches the point in the batteries sump that the plates are shorted out. One of the main differences you will find on the expensive long life batteries is the have larger sumps to handle more buildup. Starting batteries have nearly no sump. Pampering your batteries with proper charging can dramatically extend their life. Also, never store them for a long period in a discharged state. Always charge as soon as possible after use.

[Paul S]

That is one of the great new switch banks west marine has for the 3 on off switch method they recommend. No thought needed in operating it like the big red 1/2/both switch which has to be set on both for charging each time you run the motor and then back on 1 or 2 for house use.

Or as I have done, you can skip it all, hook them in parallel and get less over all wear on the whole system.

With the switch..you can still flip the parallel switch and run them like that. But with honkin 112 AH group 27 Rolls batteries..should be able to handle the load for years.. I guess you could always swap the house/starting battery every season to balance them out (kinda like rotating your tires).

Treating them right will greatly extend their life...regardless of method used.

Paul

[Robert]

AGM batteries are lead acid batteries with the acid trapped in an Aquious Glass Mat, (a sponge). The AGM "sponge" is not quite saturated with acid, this leaves room to hold the gasses that evolve and for thermal expansion, thus the AGM battery cannot leak, UPS will ship them cheap, UPS will not accept a "bucket of acid" wet cell battery at all.
..
Advantages of AGM Batteries:
1.) cannot leak
2.) no fumes in bilge / cabin
3.) no water to test / measure/ replace
4.) can be mounted without a battery box
5.) can be mounted on side
6.) will not spill when healed
7.) 10X lower internal resistance allows extremely fast charge
8.) 10X lower internal resistance allows more cranking amps
9.) 10X lower internal resistance allows lighter battery
10.) AGMs are much more vibration resistant for pounding over the choppy waves.
11.) AGM starting batteries are rated for 50 deep cycles without damage
12.) AGM batteries drastically reduce corroded connections
13.) AGM batteries will not rust out your car's battery box.
14.) AGM batteries have a far lower self discharge rate, they can sit all winter and start up your motor in the spring.
..
I just thought you ought to know. To me these advantages far outweigh the 50% higher price. Any one or two of these advantages make the AGM worthwhile in a Mac26.

[Don T]

Hello:
I got 7 years out of my first set of batteries. I remove them from the boat during the winter and charge them once a month.

[Paul S]

Not a battery expert by any stretch of the imagination. But after reading Practical Sailor, talking with other experienced boaters, reading anything and everything about batteries. I felt the wet cell was the proper choice for our boat.

I liked having a larger capacity for the size/weight. Ability to maintain it (add water, etc). Lower cost. Easy to charge.

AGM/Gell cell require special charging procedures that many owners may not know about. They do not like overcharging.

There is a market for everything. Not saying wet cells are better...but they are a better choice for my needs. They are tried and true.

Here is some info I came across (from my battery mfr) :
http://www.rollsbattery.com/Bulletins/503.htm

Paul

[mike]

AGM/Gell cell require special charging procedures that many owners may not know about. They do not like overcharging.

In the case of AGMs, this is not much of a problem from what I understand. Gels do require special treatment (lower charging voltage, etc.), but I've read in several places that AGMs can simply replace flooded batteries with no changes. While some chargers might have a setting that is optimized for AGMs, it's not a necessity.

I agree with Robert... AGMs are great!

--Mike

[Jack O'Brien]

http://www.vonwentzel.net/Battery/

[Russell]

I agree that auto manufacturers get better quality batteries. I bought my car new in 96 and the battery still works fine. I had two situations that required charging over the very cold winter but other than that it works great.

[Robert]

Thanks Jack for that link.
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I think there is no advantage at all to a Wet Cell or Bucket-Of-Acid battery over AGMs except the initial cost.
..
If you are concerned about energy efficiency, then the AGMs cost less, since their lower internal resistance does not waste charging energy by diverting it to heat up the battery. This means more charge retained in the battery from the time you have the outboard running.
..
AGMs can accept any charging that Wet Cells can. AGMs can also accept far greater (10X greater) charging rates than Wet Cells. So, when you find a charger with a special cycle for AGMs what you have is a charger that will allow a faster charge. You can safely charge an AGM battery at rates that would boil or explode a Wet Cell again due to the lower internal resistance. The AGM optimized chgargers will allow a short stop over for lunch at a dock with power to add a very fast charge to your AGM battery. This was a major concern of mine so the kids could stay entertained while I sail.

[Chip Hindes]

I think there is no advantage at all to a Wet Cell or Bucket-Of-Acid battery over AGMs except the initial cost.

As if the high initial cost weren't enough, there are at least a few others.

AGMs can accept any charging that Wet Cells can.

There is certainly disagreement on this matter. West Marine, who sells all three and therefore has no particular reason to lie about it, says both AGM and gel batteries can't be charged at a voltage higher than 14.2. So they can't be charged with conventional chargers or there is a danger they will be overcharged. Not just the cheap automotive type chargers. Some expensive chargers have special charge cycles for gel and AGM, but my fairly expensive Statpower Marine, dual battery, deep cycle charger does not. In fact, the manual specifically says it can be used only on flooded cell batteries. So the cost of AGM or gel cells for me is not only new batteries at twice the cost, it's also an expensive new charger.

Contrary to what you stated, if you inadvertantly overcharge gel cells or AGMs, they will outgas and lose water. So one of your advantages, which certainly is an advantage in most situations is actually a disadvantage in this case. They can't be topped off, and overcharging can permanently damage or destroy them. Flooded cell batteries can be charged at higher voltages, and they are less susceptible to overcharge damage. If you do overcharge them, in most cases you can simply add water.

If you are concerned about energy efficiency, then the AGMs cost less, since their lower internal resistance does not waste charging energy by diverting it to heat up the battery. This means more charge retained in the battery from the time you have the outboard running.

Funny, West Marine doesn't mention this as an advantage. In any case, given the charging rates provided by the puny charging circuits in our 50HP motors, I don't imagine the difference in charging efficiency will be significant, if it is measurable at all.

So, when you find a charger with a special cycle for AGMs what you have is a charger that will allow a faster charge.

So, it appears you are postulating yet another special charger that doesn't yet exist, and that you're proposing charging your battery at 100 amps or so (10X the rate of a flooded cell) while you're off eating lunch somewere else. When you do this, please post a sign so I can make sure my own boat is parked a long ways away.

Certainly AGM and gel batteries are superior in some ways. However, in reviewing your list of advantages, besides several statements which appear to be incorrect, there are a number of others that might be significant in some other boat, but are irrelvant in a Mac. At least in my Mac.

In my boat, I can't justify the additional expense of the batteries plus the new charger for the advantages of the AGM or gel cells. In my case, the advantages are either dubious or nonexistant.

[Dimitri-2000X-Tampa]

Isn't the dangerous gas that comes off of a battery just hydrogen? Since that is the lightest gas, I would think it would just exit via my companionway hatch leaks or my durade ventilator in the cabin roof. Is there something I'm missing?

[Jack O'Brien]

My boat came with two "no name" wet cell batteries; one aft the galley and one under the cooler bin. Had the never-used genoa next to the latter battery. Although I never saw leakage, it must have. The jenny's sail bag DISSOLVED on its bottom side laying against the bilge floor. Luckily, the sail seems ok. Now I have Lifeline AGM and have no worries or cares regarding batteries.

[Paul S]

Until AGM are tried and true..I am sticking with wetcell.


What...2 stroke are not better?

Gotta run..got to hand crank start my horseless carriage.

Paul