Time for new house bank

[Art]

There are situations where people are away from shore power for weeks or months, aren't regularly getting the bank back to full, or are too often drawing below 50%.

Knowing, really knowing with accuracy their SoC is then critical to getting the system to where they'll get 12-15 years from that multi-thousands bank rather than murdering it in 3-5 years.

For that kind of scenario voltage alone just doesn't cut it, and even with SG one should get the SoC correspondence chart from the maker.

But I do realize this is more rare in the world of trawlers than cruising sailors or even expedition/RV/caravans.

All right, all right!! You are surely true in your statements that it is another good way to check battery condition via hydrometer readings of SG and Soc when on long voyage or anchored for weeks/months. But, please don't forget... in many boats it is a contortion exercise to get into hydrometer check-position for every cell.

Therefore, on a multi year old battery: Will checking SG or SoC actually expand it's life span any more than simply using a multi meter through wired into a comfortable to access cabin placement position? So by flick of a switch you can make sure to not drain batts down past 50% level and also make sure that batts are getting charged amply to reach 100% charge??

Seems to me that LA deep cycle batts just need to be kept filled with distilled water, not let go down past 50% charge and recharged most times to 100%. That procedure gives LA batts the best chance for long life. If a batt gets old enough to where it won't hold a charge and/or it too quickly discharges then that is called a "Bad-Batt".

Of course, once a batt has seen its day pass and it simply has run the course after years of service then it is time to replace. Also, IMO - If after years of service [ours is 8 yrs. old] considering you have a multi batt parallel run batt bank [we have four G31 LA, deep cycle] for house power or anything else [our batt bank also starts engines] and one or two batts give up the ghost, i.e, become "bad-batts"]... then it is time to replace all the batts. Reason is: Even if a couple of the many year old batts still seem OK you can be sure that in near future they too will go bad and drag down/ruin the couple of new ones recently installed.

Batteries on a boat are important of the overall power package. Boat batts and all the many levels of batt equipment can become very expensive [multi thousands] or kept to a basic minimum [under a thousand].

The batt system complications and expense as well as living comfort and energy service availability of batts on a boat is at the sole desecration of boat owner. Research is necessary for any boat owner to arrive at the batt-package they want aboard their boat. God knows there are enough links on Google as well as threads in forums to satisfy all inquiries about marine battery power.

Happy Batt Daze! - Art

 

[john61ct]

in many boats it is a contortion exercise to get into hydrometer check-position for every cell.

Which is why my recommendation is for a simple accurate SoC meter like SmartGauge.

Will checking SG or SoC actually expand it's life span any more than simply using a multi meter through wired into a comfortable to access cabin placement position? So by flick of a switch you can make sure to not drain batts down past 50% level and also make sure that batts are getting charged amply to reach 100% charge??
...
Seems to me that LA deep cycle batts just need to be kept filled with distilled water, not let go down past 50% charge and recharged most times to 100%.

My main point is that voltage does **not** give you that information, varies too much based with current levels, resting time etc.

If a batt gets old enough to where it won't hold a charge and/or it too quickly discharges then that is called a "Bad-Batt".

Of course, once a batt has seen its day pass and it simply has run the course after years of service then it is time to replace.

The whole bank needs to be repaced together, LONG before that point for off-shore cruising/liveaboard.

Best practice is when the declining AH capacity is down by 20-25%.

Which can only be determined accurately by a 20-hour load test, ideally based of a benchmark established when the bank was installed new.

Letting it go past that point geometrically increases the odds of a catastrophic failure far from shore. After the 20% point things deteriorate rapidly anyway, that is when industry defines batts as scrap lead.

Again, day-trippers and weekenders just hours away from a marina will tolerate greater risks.

Your boat your call. . .

 

[Art]

Your boat your call. . .

So true!

May we all row to heaven in a non batt boat! :lol:

 

[FlyWright]

As I've been saying for several years on this site, IMO, the very best monitor system would incorporate the SOC meter like the Xantrex LinkPro or Victron) with its AH in/out display and the Smartgauge SOC indication. To some it seems like a belt and suspenders approach to battery monitoring, but it's the best affordable presentation of the combined data of the 2 systems.

When I can free up another $300, I'll be installing a Balmar Smartgauge.

 

[dhays]

When I can free up another $300, I'll be installing a Balmar Smartgauge.

$280 from Rod Collins (CMS)

http://shop.marinehowto.com/products/balmar-smart-guage

 

[foggysail]

Art--

My chargers, Xantrex 5012 along with my current poly panels provide enough charge current to bring my batteries to float. We were/are getting ready to be away from the dock for awhile so before we leave I took to replenishing the batteries with distilled water. Before doing so things looked just fine but with my hydrometer, not so. Heck, I forgot all the numbers on an hydrometer but all my readings were in red. Further charging along with equalization did nothing.

Had I not check the batteries with an hydrometer, we would have been stuck out there because I rely on batteries for the fridge (self defrost) 2 TVs, lights and all the other loads typically placed on a battery bank. Maybe clever voltage readings might have helped but I doubt it.

While at my keyboard, I purchased 8 of Sams 215AH Duracells. Sure, a better choice would be T105s. A local guy on Craigs is peddling them for $140 but that is $56 more than the $84 Duracells. So... to each his own for batteries.

 

[john61ct]

As I've been saying for several years on this site, IMO, the very best monitor system would incorporate the SOC meter like the Xantrex LinkPro or Victron) with its AH in/out display and the Smartgauge SOC indication.

Yes the SmartBank Advanced + BMV-702 is the way I'm going. Bruce at Ocean Planet says he sells plenty combos like that.

The programmable relays act as a DIY proto-BMS as well.

 

[dhays]

While at my keyboard, I purchased 8 of Sams 215AH Duracells. Sure, a better choice would be T105s. A local guy on Craigs is peddling them for $140 but that is $56 more than the $84 Duracells. So... to each his own for batteries.

I don't think you can go wrong with those on a $$/useful Ah basis.

 

[john61ct]

The solar version T-105-RE would be a big step up from the Duracell, if your usage patterns and infrastructure can maximize longevity, it'd be worth paying up to double per AH, especially if the replacement process is a pain.

The non-RE versions, I'd pay a 50-60% premium.

But people not sure they'll be able to care for them properly should IMO stick to the Sam's.

 

[dhays]

I thought I would give an update to my new house bank now that we have had a chance to be out and use it.

I replaced the original Chinese SLA batteries with 4 x US Batteries AGM 6v L16 scissors lift batteries. Nominally, this should give me a total of 780 Ah. I wanted to be able to keep my SOC above 70% overnight while running my wife's c-pap off the inverter along with all the other demands. We have a refrigerator as well as a 12v cooler on the aft lazarette. There are also some small 120v drains on the system through the inverter as well.

So far, it has worked well. The only time we got close to 70% SOC overnight was when I also had three of the 120v Air-dry dehumidifiers going overnight. We got down to about 73% SOC. Last night, I didn't run the dehumidifiers and we got down to mid 80s % SOC.

We have been running the generator for a few hours in the morning and evening. Max amps the charger will kick out is about 128 (only rated for 125amps). With the high acceptance rate of the AGM the time in Bulk charging is much less than my prior bank. This morning, it almost immediately went from Bulk to absorb.

We have a 6k watt generator. Which if my math is correct, should produce 50amps. With the charger maxing out at 127 amps, plus turning on the water heater, stereo, all dehumidifiers etc... we are using exactly 50 amps. That means I need to either wait for the charge rate to drop on the charger or turn off the water heater so I can make coffee. I will run the genset until the batteries go to float. This means they are a bit under charged unless we are going to be running the boat for a few hours but with our use they aren't chronically left undercharged.

Anyway, so far I have been really happy with the batteries. They seem to be secured well enough as the seas we had crossing Juan de Fuca gave them a good pounding.

I would love some solar to use. Even a bit would mean that I could run the genset in the morning only and the solar would keep the batteries topped off during the day, at least during the longer summer days here.

 

[Pack Mule]

Nice job Dave . When it comes to batteries and electrics on the boat I'm weak . I can limp along and get it done but never very confident about what I'm doing . Thanks for posting.

 

[dhays]

Nice job Dave . When it comes to batteries and electrics on the boat I'm weak . I can limp along and get it done but never very confident about what I'm doing . Thanks for posting.

Lol, I really have no idea what I'm doing. I just take the advice of the folks that actually know their stuff.

 

[john61ct]

Yes, great work.

I bet that 12v cooler is super inefficient compared to a proper portable compressor type, maybe investigate investing FFR.

And **for sure** on the solar, even a small setup will greatly reduce genny run time and extend the lifespan of that new bank, which currently won't **ever** get to 100% full away from shore.

 

[dhays]

Yes, great work.

I bet that 12v cooler is super inefficient compared to a proper portable compressor type, maybe investigate investing FFR.

And **for sure** on the solar, even a small setup will greatly reduce genny run time and extend the lifespan of that new bank, which currently won't **ever** get to 100% full away from shore.

The cooler is actually a Nova-Cool freezer/fridge. It came with the boat when I bought it and the PO had a 12v outlet installed next to it in the cockpit. It works amazingly well. Last year it kept frozen food solid even in 90+ degree weather.

The solar has me intimidated in two ways. The first is the design and selection. The second is the hassle of running wiring. I think it is something that I may look at for a winter project.

 

[john61ct]

Aha. What I call 12V coolers, mass market cheap stuff, not worth even considering both inefficient and ineffective.

Yes solar's a big project, but starting on the decision-making should be long before the hands-on.

 

[foggysail]

Aha. What I call 12V coolers, mass market cheap stuff, not worth even considering both inefficient and ineffective.

Yes solar's a big project, but starting on the decision-making should be long before the hands-on.

John.... not sure I understand your comment about 12v coolers. Did you refer to the Dave's refrigerator? Yeah, I know, I'm being picky but any cooler, even the inefficient units, that successfully keep contents cool/cold cannot be called "ineffective."

Don't misunderstand, I am not a fan of marine fridges or ice makers. Typically they cost three times that which a comparable, house/apartment equivalent product costs. Sure, the less expense house/apartment products operate on 120vac, not 12vdc. Modern inverters are equally inexpensive and should be considered as a cost effective AC alternative for the system.

 

[dhays]

I think he was referring to the mass-market 12 coolers that are designed to plug into a car. They aren't really very good. However, they are pretty inexpensive. Then there are some very effective chest fridges like the Nova-kook that actually work quite well. It are really speedy.

 

[foggysail]

AHhh-- OK, that would make sense. Those devices most likely use what is known as Peltier Generators which are semiconductors. One side of the device gets cold while the other side gets hot as current passes through. They act as heat pumps.

They do require cooling the heated side just as a heat pump does. Air conditioners are heat pumps although those I know of use compressors. If I failed to point out "those I know..." someone would find an exception

 

[john61ct]

Love those Nova-kooks!

 

[BruceK]

Dave, review your fear about installing solar. We did our own, it`s been good for 6 years. Using my legal skills, with input from a computer guy who has made a system, some online research (Casey), I designed it. I had help from someone qualified in electrical engineering(telephony) with wiring skills, but little 12v experience. Panels and controllers bought on Ebay, I made the mounting brackets from teak and angle aluminum. I later added a small panel dedicated to the genset batt. Start by thinking about it, do some design planning,research products, it may look less complex. And if it doesn`t, there must be plenty of pros with the skills to do the job you already know will be worthwhile.
I had a Peltier type portable "fridge" I quickly replaced with a Danfoss powered Waeco/Dometic, which has been great.

 

[foggysail]

Bruce-

Agree with your suggestions to Dave pertaining to solar. I hope to take some pictures of how I mounted my panels onto two hard tops. I took a simple approach for mounting the panels by attaching them using silicon caulking to the frames.

My first set of solar was secured with 5200 which I had to remove when I replaced 145 watt panels with 295 panels. It was not an enviable job to remove the 5200. I don't recommend using 5200 unless there will never be a need to remove it.

 

[BruceK]

Two reasons not to screw the panel brackets to the deck:
First to not penetrate the deck.
Second so the polyurethane adhesive/glue(like Sika 291) took up any deck unevenness avoiding panel stress or damage.
I screwed vertical aluminum angle to the panel frames (short screws), screwed the horizontal angle to 1" high teak strips, then glued the teak strips with panels attached to the deck, using generous sealant/adhesive allowing for any irregularity, before cleaning up.

 

[foggysail]

Right on, don't screw anything if avoidable. I purchased plastic boards at Lowes and cut them into strips. I placed a strip under one edge of the panels so that the top surfaces are reasonably flat. I considered wood/teak but plastic was my choice.