Time for new house bank

[john61ct]

Do you have solar charger hooked into batt bank; and, if so what size and how well charged does that usually keep those big batts?

Mobile solar won't handle bulk from 50%, but is ideal for "the long tail" which is low amps.

Max-sized charge on dino juice up to 80-85% in the early morning, then solar all day to get the bank to 100%, is the perfect combination.

With high-CAR AGM, ideal would be over .3C, 400+ amps in this case.

120A would be barely scraping by, bank's longevity would suffer.

 

[ranger58sb]

The batteries are in the aft lazarette underneath the cockpit. They are not easily accessible with very little overhead clearance. In this same space are the thruster batteries, DC electrical panel, and a diesel hydronic furnace. I can changed the form factor of the batteries if needed.

I would prefer to not go with the 8D size again.

Here are the options as I see them. I am also open to others I haven't thought of.

Wet GC2 batteries
8D AGM
Firefly Oasis:

AGM GC2?

I've studied on our upcoming bank replacement for about the last 5 years... and eventually decided that ease of service (essentially not much), lessened off-gassing (ditto), and the combination of cranking amps /amp-hours were my main criteria BUT our space is limited so I only had a few options. The Lifeline GPL-4CTs (~AGM GC2s) go in probably sometimes next week.

But for your case...

1) If AGM 8Ds are an option, then so should be wet 8Ds, basically a one for one replacement on your current system. A watering system, hire a mule to remove the old and drop in the new... WAY less expensive than AGM 8Ds.

2) If wet GC2s are an option, then so should be AGM GC2s. (I dunno what impact off-gassing might have with that diesel heater nearby, but... it's been there for years, yes? Maybe not much impact? Maybe not much argument in favor of AGM GC2s if you can do a watering system anyway?) I've gotten good and troublefree service from AGMs.

3) If GC2s are an option, maybe the taller versions would also be an option? (I dunno model numbers, maybe L16s or some such. I didn't study much on that idea myself, 'cause I don't have the vertical clearance...)

4) If Firefly Oasis are an option -- G31 form factor -- than any other G31 form factor batteries could be an option, too. As I understand it, the carbon foam advantage is all about PSOC operations... but if you can charge effectively during an outing and then completely recharge effectively after that outing, then the PSOC advantage might not be worth the $$$ premium. Which in turn leads to any decent wet G31s plus watering system, or decent AGM G31s, being options. Latter is what we've used; our oldest bank of 3x Odyssey PC-2150s (G31s) is what we're replacing... and those Odysseys were installed in March 2006. And we simply charge 2x/day when we're at anchor (coinciding with electric cooking times) and then recharge at the dock. Seems to have worked fine.

(We've also recently added an inverter/charger, so that our main banks are both now charged by a dedicated charger. Don't have results from that yet, but my expectation is that we're get even better results from charging while at anchor.)

5) Form factor might trump some of all that. Some number of GC2s (three, I think) will fit almost exactly into the space of a single 8D. If that's correct, then 9 GCs will fit where 3 8Ds fit... and 9 is maybe an inconvenient number, although maybe not a big deal. The G31/8D ratio is different, more like 2½ per 8D maybe (not sure); I know I can't put two 8Ds in the space I have, but I was able to put 3 G31s there...

-Chris

 

[ranger58sb]

The batteries are in the aft lazarette underneath the cockpit. They are not easily accessible with very little overhead clearance. In this same space are the thruster batteries, DC electrical panel, and a diesel hydronic furnace. I can changed the form factor of the batteries if needed.

Separate thought: are the "thruster" batteries in that lazerette for stern thruster only? Or both bow and stern? Or...?

I've read that batteries being located nearer a bow thruster is better...

-Chris

 

[motion30]

A question for the experts , are there any wet cell 8 D batteries that are actually deep cycle? I had 8d lifelines in my last boat and was extremely disappointed in their life span I replaced 5 8D Dual Purpose batteries in my current boat with 12 6 volt GC batteries. I have much more capacity and never wake up to voltage below 12.5. I have been on the hook for a year-and-a-half

 

[john61ct]

https://www.dcbattery.com/rolls.html

 

[dhays]

Separate thought: are the "thruster" batteries in that lazerette for stern thruster only? Or both bow and stern? Or...?



I've read that batteries being located nearer a bow thruster is better...



-Chris

Good point Chris. That bank is in the stern and powers the stern thruster, bow thruster, windlass, and crane. The windlass and bow thruster take a long cable run. Not ideal but it is the way all these boats are setup. They just use very large cable for the run. They also run a single cable to the forward end of the ER. There is an auxillary DC panel there that contains the relays to switch power to the bow thruster and windlass. From there there are separate runs to the bow for each.

NorthPacific could have put 1 8D in the bow for the bow thruster and windlass, and then 1 8D in the stern for the stern thruster and crane, but I think they felt that a larger bank gave more flexible capacity and was worth the loss from the long cable runs.

In any event, I don't intend on changing that at this point.

 

[Ted]

Would like to use GC batts but can't fit them.
Have 9 Interstate 1850 12volt deep cycle, 200ah. 15 1/2 x 7 7/8 x 10 high.
Space filled, would need 18 GC, only room for 13 or 14. .RATS!!

Ted

 

[john61ct]

Interstate only markets batteries, doesn't manufacture them.

I am very skeptical of "deep cycle" claims in 12V, maybe good but dunno, I would want spec sheets and charts, e.g. cycling vs DoD, from the actual maker.

 

[Art]

Batteries Plus sells batts made by East Penn. I've had good luck with both the BP store and the EP batts. I have four [4] G31 deep cycle LA wets in parallel used as house bank and as twin engine starter batts. Installed them spring 2010. So far so good! I only need to water em about once per year. Luckily all batts are reasonably easy access.


Also have G27 starter batt for gen set and G27 starter as isolated [always kept fully charged] emergency batt in its own private batt box. Total cost for those batts and 1 amp charger [for emergency batt - that is only activated when AC breaker is activated] was under $600. Don't think cost now [7 yrs. later] would be too much more??


Next time I put in new [hopefully not for a couple more years] I'll probably repeat same set up. These batts meet my/our needs. We are conservative on DC power usage, and, I adore the term - KISS!!

 

[Datenight]

You and I have similar setups. I have 5 8Ds in the lazarette, 3 house and 2 thruster.

Are you concerned about gas venting in that space?
Do you have a diesel furnace in the Lazarette?
What watering system do you have in mind?
Are you combining the house with thruster banks?

Dave,

I think I have enough ventilation as the batteries are there now. No diesel furnace. I have about 12-14" above the batteries so will not have to put the watering system in right away. Not sure what I would use but have some time to research.

If I read my wiring correctly the house and thruster/windlass bank are combined now. I do have a qualified marine electrician consulting to be sure I do everything right.

Unrelated, I would like to use my 8-D boxes. Trojan 105's are 10.3" long. My box is just over 20" at the bottom and 21ish" at the top. Does anyone know if the 105's are shorter along the base of the battery? If 10" along the bottom I can use my original boxes.

Thanks,

Rob

 

[twistedtree]

It's not clear to me whether some or all of Dave's batteries are AGMs vs flooded (even if "sealed"). But there are some important enclosure considerations if the original batteries were AGM and you are considering switching to non-AGMs.

For flooded batteries you need to consider ventilation, as discussed. But it's generally not a big issue since the released hydrogen is lighter than air and dissipates easily. But flooded batteries also need to be in cases that will contain the acid if spilled. This is based on ABYC which is not mandatory, yada yada yada, yes you can do whatever you want, but is a good and sound practice none the less.

AGMs, on the other hand, can be installed anywhere with no enclosure required. So if you are replacing such an AGM with flooded CG or the like, you will need to add a case if one isn't already present.

Just something to keep in mind for those contemplating conversion.

 

[dhays]

Angus, how did you end up securing your bank of batteries. I recall that the photos a you took were before you had that secured.

 

[john61ct]

It's not clear to me whether some or all of Dave's batteries are AGMs vs flooded (even if "sealed").

Not sure what that last means.

Flooded (FLA) means caps come off so you can top up or measure SoC with a hydrometer.

VRLA, or sealed lead (SLA), include AGM, Gel and others where you can't.

Under certain conditions they do vent, and may even lose electrolyte.

But in classifying battery types, the two are mutually exclusive.

Yes, a tray or other acid containment is more necessary with flooded than sealed.

But I would want that with any lead batteries myself.

 

[john61ct]

Trojan 105's are 10.3" long. My box is just over 20" at the bottom and 21ish" at the top. Does anyone know if the 105's are shorter along the base of the battery? If 10" along the bottom I can use my original boxes.

Length 10.30" (262mm)
Width 7.11 (181)
Height 11.07 (281)

 

[john61ct]

Batteries Plus sells batts made by East Penn.

They sell batteries from many different vendors, both actual manufacturers and re-labelling brand marketers.

The Duracell (actually East Penn) GC2 is the same as that sold by Sam's Club

B+ is a great resource, but I would not take the word of any employee in a retail environment without getting more objective confirmation.

And only but batteries where the spec sheets and charts are available from the actual manufacturer's tech support.

 

[dhays]

It's not clear to me whether some or all of Dave's batteries are AGMs vs flooded (even if "sealed"). But there are some important enclosure considerations if the original batteries were AGM and you are considering switching to non-AGMs.

For flooded batteries you need to consider ventilation, as discussed. But it's generally not a big issue since the released hydrogen is lighter than air and dissipates easily. But flooded batteries also need to be in cases that will contain the acid if spilled. This is based on ABYC which is not mandatory, yada yada yada, yes you can do whatever you want, but is a good and sound practice none the less.

AGMs, on the other hand, can be installed anywhere with no enclosure required. So if you are replacing such an AGM with flooded CG or the like, you will need to add a case if one isn't already present.

Just something to keep in mind for those contemplating conversion.

Good questions. Currently, there are 5 8D sealed LA (wet) batteries in the space. These are Valve Regulated Lead Acid batteries but are not Gel or AGM VRLA batteries. I don't understand this stuff but my understanding is that the VRLA batteries attempt to capture and remix the gases (h2 and O2 I believe) that are generated when the batteries are recharged. These gases are then remixed with the electrolyte. If the pressure builds up too much, the gases are released by way of a pressure relief valve (hence valve regulated lead acid). Gel and AGM work the same way as as the sealed wet cell in this regard.

So, in my lazarette I have not been getting much gassing as the batteries are designed to retain it. This makes me less than eager to go to a standard wet cell as those gases would be released rather than retained and released into a closed space with possible ignition sources.

My 8D batteries are in fiber glasses boxes and I should be able to use the same boxes if I went with 8D batteries again. Potentially, I might be able too use the same boxes if I went with AGM GC2 batteries.

I could just stay with a non-AGM VRLA batteries and save myself some money. As I understand it, the primary advantage of the AGM is the ability to more rapidly absorb a charge. This would be helpful when running a generator to recharge the batteries. I am not sure what affect this increase rate of charge may have on my engine alternator however.

 

[Datenight]

Length 10.30" (262mm)
Width 7.11 (181)
Height 11.07 (281)

Thanks John. I had that measurement and it will work at the top. I have noticed the top on some batteries is a little longer than the base. If the base is 10" they will fit my boxes as they are wider at the top 21", than the bottom 20 1/8".

Rob

 

[john61ct]

I could just stay with a non-AGM VRLA batteries and save myself some money. As I understand it, the primary advantage of the AGM is the ability to more rapidly absorb a charge. This would be helpful when running a generator to recharge the batteries. I am not sure what affect this increase rate of charge may have on my engine alternator however.

Be aware that the high CAR only speeds up the early stages <80%, after that, still hours at low amps needed to get to 100%.

If you're in effect expanding your House size with the LVD-consolidation idea, you may never be getting below 20% anymore

Which of course at least doubles their lifetime.

Sorry if I missed it, have you got solar?

I believe there are non-AGM with high CAR, likely from top-shelf mfg, but thus unlikely they will save much money against all but the top-notch AGMs.

Another issue is that AGMs are more sensitive to charging volts being well-regulated, straight LA is likely to just be more robust, but if you do go quality AGM, be sure to match it up with your existing infrastructure, or v/v

For example, Odyssey specs .4C in charging current as the **minimum** rate for max longevity.

Lifeline and Northstar are the other two good mfg to look at for AGM, as with Rolls/Surrette for plain lead.

 

[john61ct]

Thanks John. I had that measurement and it will work at the top. I have noticed the top on some batteries is a little longer than the base. If the base is 10" they will fit my boxes as they are wider at the top 21", than the bottom 20 1/8".

Rob

Is the tray at all flexible? Third of an inch may be bit of a stretch ( did you see what I did there?

I'd call your mfg of choice tech support and ask.

 

[twistedtree]

Not sure what that last means.

Flooded (FLA) means caps come off so you can top up or measure SoC with a hydrometer.

VRLA, or sealed lead (SLA), include AGM, Gel and others where you can't.

Under certain conditions they do vent, and may even lose electrolyte.

But in classifying battery types, the two are mutually exclusive.

Yes, a tray or other acid containment is more necessary with flooded than sealed.

But I would want that with any lead batteries myself.

I agree with your definitions, which is why I put "sealed" in quotes. I've seen a lot of batteries that are "sealed", or "maintenance free" that are actually just flooded batteries with difficult or impossible to remove caps. The later are flooded batteries that will leak if tipped over, and really no different from FLA with conveniently removable caps.

Dave mentioned something like "Chinese made sealed LA 8D batteries". I wouldn't assume those are AGM or Gel batteries, and think they are more likely flooded batteries with hard to remove caps. But I don't know.

 

[Art]

They sell batteries from many different vendors, both actual manufacturers and re-labelling brand marketers.

The Duracell (actually East Penn) GC2 is the same as that sold by Sam's Club

B+ is a great resource, but I would not take the word of any employee in a retail environment without getting more objective confirmation.

And only but batteries where the spec sheets and charts are available from the actual manufacturer's tech support.

I work with store owner. Was one of his first customers and a continued customer of his.

 

[Simi 60]

When the letters AGM are spoken, one cringes at the cost. IMHO, they are worth every penny!

No flinching in Australia.
AGM's are pretty much the same price as Trojan GC wet's
Mind you, the Trojans here are 5x what you pay.

 

[Art]

I agree with your definitions, which is why I put "sealed" in quotes. I've seen a lot of batteries that are "sealed", or "maintenance free" that are actually just flooded batteries with difficult or impossible to remove caps. The later are flooded batteries that will leak if tipped over, and really no different from FLA with conveniently removable caps.

Dave mentioned something like "Chinese made sealed LA 8D batteries". I wouldn't assume those are AGM or Gel batteries, and think they are more likely flooded batteries with hard to remove caps. But I don't know.

IMO "sealed" or very difficult to remove water cap batteries are simply a battery waiting till enough moisture is gone so that led cell tops get exposed and the battery then quickly dies. All LA flood batts need to have distilled water added when the level gets low. "Sealed" LA flooded batts have a vent for gas to go out of cell while charging, that is a MUST! Out that vent also goes cell moisture... thus... eventual need to add water.

 

[Larry M]

No flinching in Australia.
AGM's are pretty much the same price as Trojan GC wet's
Mind you, the Trojans here are 5x what you pay.

That's a pretty easy decision.

 

[dhays]

Be aware that the high CAR only speeds up the early stages <80%, after that, still hours at low amps needed to get to 100%.

If you're in effect expanding your House size with the LVD-consolidation idea, you may never be getting below 20% anymore

Thanks John, I think the first thing I am going to do, before I change the batteries I have, is to combine the house and thruster banks into one large one. While not ideal, that may give me some added capacity, enough to get my wife's CPAP through the night. That will buy me a little time.

If I can come up with a way to make a suitable battery box, I really like the option that Angus used with those group 902 AGMs. 8 of those would give me a good sized bank in an easy to manage size.

 

[Simi 60]

Good article here I just stumbled upon.
Helps explain some of the vagaries I have struggled with over the last year as an on the hook live aboard.

Nordhavn - premature battery death

 

[HenryD]

Take a look at the Lifeline GP-L16T batteries...increase AH in same footprint if you have vertical space. They are AGM and lighter than 8D to move around.

 

[cardude01]

I would go with the AGMs for simplicity. I replaced my bank with Lifeline group 31 AGMs because they were not easily accessible and I'm lazy. I've been happy with them, but it's only been a couple of years.

 

[Datenight]

Is the tray at all flexible? Third of an inch may be bit of a stretch ( did you see what I did there?

I'd call your mfg of choice tech support and ask.

John,

I spoke with the distributer who measured a battery in stock. Looks like they will fit.

Rob

 

[Art]

Good article here I just stumbled upon.
Helps explain some of the vagaries I have struggled with over the last year as an on the hook live aboard.

Nordhavn - premature battery death

Thanks for posting link to the detailed article.

I must be doing something right... our house bank of four G31, deep cycle, East Penn, wet LA batts wired in parallel seem to be doing OK during their 7th year. Of course, we do not use our boat anywhere near a regularly as many Nord owners do