Bygge batteribank til forbruk, er det Gel eller AGM som er best?

[logget av]

Takk for info. Hva er feil med ladesystemet?

I båter som skal på langtur er det spesielt viktig at alle ladekildene gir batteriene riktig absorberingstid, og for batterier med tykke plater så må man lade lenger. Problemet har da vært at absorberingstiden har vært for kort med det resultat at batteriene lades med floatladespenning for tidlig.

 

Når båtene da utstyres med elektrisk utstyr som ved riktig innjustering håndterer dette på en utmerket måte så er det en forutsetning at utstyret justeres før levering. I tillegg har HR levert båtene med ekstra dynamo og Mastervolt regulator. Denne regulatoren er ikke egnet til traksjonsbatterier og de burde derfor valgt et annet merke.

 

Når det gjelder problemet med batteriene så kan jeg opplyse om at mastervolt batteriene (Leoch) takler en float ladespenning på mellom 13,2 og 14 volt bra, og hvis man har et problem med batteriene etter 3 sesonger så må man nok lete etter feilen et annet sted.

 

Jeg hadde lagt press på de ansvarlige som uttaler seg. Det burde være i alles interesse å finne ut hvilken feilmekanisme batteriene har utviklet, for det er først da man kan si noe om den mest trolige årsaken. (Jeg tipper fremdeles at en god del av cellene er uttørket, og da er det ikke så vanskelig å resonere seg frem til den mest sannsynlige årsaken).

[Bitteliten]

Takk for interessant info. Float hos meg liggerpå 14,05 sånn ca. På MICC står det 1 på antall sykluser batteriene har vært gjennom. Den kom i sommer da batteriene gikk helt tomme.

Men Mastervolt skal kunne lese ut all historikk fra systemet så da bør man få svar på hva som har skjedd.

 

Ser ut som om vi skal ha en skikkelig gjennomgang av andre enn HR før vi legger ut på langtur (men etter at NW kjøpte Najad kan det jo være at det blir et alternativ også)

 

Hvordan setter man systemet i vintermodus? Jeg har lest det meste av bruksanvisninger og kan ikke erindre noe om det. Tidligere år har jeg vært opptatt av å slå av inverteren da den ligger og drar ca 1Ah i døgnet bare ved å være på. Noe annet som skal gjøres?

Redigert 17.Oktober.2011 av Bitteliten (see edit history)

[Joerg Becker]

.. at mastervolt batteriene (Leoch) takler en float ladespenning på mellom 13,2 og 14 volt bra,

...skepptiisk....

Det jeg hører fra tyske og nederlandske kollegaer høres da ikke så optimistisk ut,

derfor mener jeg at man burde være forsiktig med akkurat å anbefale den grensen som permanet vedlikeholdspenning.

 

Omvent hørte jeg fra kunder at det fantes tegn for "slapphet" etter en stund med bare 13,3V

som forsvant igjen når den gikk gjennom en "forfriskelsestrinns" dvs. en hel ladegjennomgang.

 

Nå har ikke jeg så mange kunder med Leoch, vet du eller noen andre mer?

 

Jørg

[logget av]

Det er sunt å være skeptisk, og jeg sier ikke hva som er optimalt. Det jeg vil frem til er at hvis floatladespenningen ligger i dette området så blir ikke batteriene ødelagt i løpet av tre sesonger for disse batteriene er for robuste til å utvikle en slik feil på så kort tid.

Med andre ord så er jeg skeptisk til at noen automatisk setter fokuset på floatladespenningen i slike tilfeller, for jeg tror årsaken er en helt annen inntil det motsatte er bevist.

Jeg installerte Leoch batterier lenge før Mastervolt tok disse batteriene inn i sitt sortiment, og jeg gjorde da en rekke tester på kapasitet og CEF for å finne ut hvordan man fikk optimal levetid og syklingskapasitet. Ingen batterier har tatt kvelden enda, men jeg har sett batterier av samme type som har tørket ut som følge av feil oppsatt system og eller at de har blitt lagret feil.

Når det gjelder å lese ut informasjon fra batterimonitoren så er jeg også skeptisk til dette, for det er ikke slik at denne forteller alt. Dette er alltid noe man må ha i bakhodet, men dessverre er det slik at mange leser ut disse dataene uten å skjønne hva de er gode for, og så trekker man en konklusjon ut av hatten.

Svaret på gåten ligger i batteriene, og som jeg skrev tidligere så tipper jeg at noen av cellene er tørre? (Men det enkleste blir jo som regel aldri sjekket).

[Bitteliten]

På min båt er det et komplett Mastervolt anlegg oppsatt ihht spesifikasjoner fra Mastervolt.

[eivindch]

 

Jeg snakket om mine opplevelser med forhandleren som ba med ta dem med slik at importøren skulle sjekke dem. Jeg er spent på å høre hva de konkluderer med.

 

Jeg tror nok jeg kommer til å gå tilbake til gammeldagse, åpne batterer.

 

 

Da har jeg fått tilbake batteriene. Tilbakemeldingen var at importøren eller grossisten ikke forsto hva som kunne ha skjedd med dem, men da de var mer enn 2 år gamle, var de utenfor garantitiden. Batteriene er av type Varta Ultra Dynamic E39. Det står på dem: ”New technology – Double life time”. Da konstaterer jeg at dobbel levetid er 4 år. Jeg synes forventet levetid på 2 år er noe snaut for konvensjonelle batterier. Jeg har hatt åpne batterier som har vart i 14 år. Startbatteriet i båten er Optima Red Top og er snart 15 år. Det har foreløpig ikke vist noen alderdomssvakheter. Men – da er jeg foreløpig vaksinert mot AGM-batterier (bortsett fra Optima og sannsynligvis Maxxima) og vet hvilket fabrikat jeg bør være forsiktig med.

 

Eivind

[Joerg Becker]

Batteriene er av type Varta Ultra Dynamic E39.

Så mye jeg aner finnes det 5 år garanti fra Varta på dette batteriet.

Jeg er ikke 300% sikker men det kan jo du undersøke nærmere.

 

Ellers, kjøpte ikke du i Norge?

 

Jørg

[Bitteliten]

Jeg bytter 6 226 ah Mastervolt batterier nå. Noen som trenger moring? Jeg heller i mot at de er ladet i hjel pga for høy float spenning over lang tid. Kommer til å endre lademønster nå slik at båten ikke konstant ligger med lader på. Vurderer også å redusere float spenning til 13,4 v

Redigert 31.Oktober.2011 av Bitteliten (see edit history)

[DieselDahl]

Nissan Leaf mener at batteriforringelse ikke dekkes ihht kjøpsloven.

Forbrukerrådet er igang med å se på saken om forventet batterilevetid på elbiler, det samme er importørenes jurister. Dette kan være interessant også ifm dyre båtbatterier som markedsføres med at de har lenger levetid. Prinsippiellt må jo den høyere prisen på AGM kunne forsvares ved at du faktisk får dekket nye batterier hvis de ikke holder hva de lover, men det kan være noe upløyd mark pga norsk forbrukerkjøpslov.

[Bitteliten]

Jeg har et agm på ca 200 Ah på hytta. Lades med solcelleanlegg som er ca 25 år gammelt. Det gir neppe mye ladespenning ( har aldri målt volten inn på batteriet). Det blir toppet med en 50 Ah lader når det trengs når vi er på hytta. Blir spennende å se hvor lenge det batteriet varer selger påstår min ti år

Redigert 31.Oktober.2011 av Bitteliten (see edit history)

[Servicemannen]

Noen installasjoner av store systempakker fra Mastervolt har 5 år verdensgaranti på hele oppsett, batterier inkludert. Jeg synes merkelig om Nord West ikke har fått til et slik avtale i din båt, Bitteliten.

[Careka]

Låner dette fra Regina sin hjemmeside. her er det bra forklart, det meste.,

http://www.reginasailing.com/

 

På hjemmesiden hans kan der leses mer.

 

 

Current Monitoring

To interpret an Amphour-meter

“The battery gauge”, that’s what many call the little instrument. Being able to check how much power you have left is a good thought. But the amphour-meter needs to be calibrated and may show so much more than just this. Correctly interpreted, the amphour-meter quickly becomes your most important instrument to monitor and improve your charging system.

.

 

The service-batteries in a boat are working hard, especially when one is out cruising and living onboard with long periods between marina berths. Compared with their engine start colleagues, they must withstand regular deep discharging, something starter batteries are especially bad at. A starter battery is made for working during just a few seconds each time, after which it becomes re-charged again. To be able to free up as much current as possible during this short period of time, the lead plates inside the starter battery are many and thin to allow for maximum surface for the heavy chemical reaction. A service battery, on the other hand, is designed for quite the opposite. Starter batteries inappropriately used for service may last as short as a couple of months onboard a serious cruising boat.

 

The fact that many sailors seem to do all right with starter batteries for service, nevertheless, can only result from frequent access to shore power, frequent motoring or thanks to the fact that discharging is made to no more than 20-30% of the battery’s capacity. If you are among these, you may stop reading here. This article is for the sailor who likes to anchor. Learn to read amps, volts and amphours on your amphour-meter, and you will soon be able to build an effective charging system. At the same time, you can react immediately, should something not be as usual.

A true deep-cycle battery also found in numerous golf-carts.

 

Lets take the easy part first: Discharging. Here, you read the current, which is drained from the battery (measured in amps, A). Is everything switched off, it should read 0A. If not, you might have a leakage, like a lamp that is left on. Switching on applications one by one, the current increases while you may observe how much the individual equipment actually is consuming. So far, everything should be as clear as an anchorage in the Caribbean.

Fruther to current, voltage and amphours, the Ah-meter can also show the battery status in percent.

At what stage are the batteries then getting “empty”? Well, that is when a certain amount of current (A) has been consumed during a certain number of hours (h). Batteries are either drained by much current during few hours or little current during a longer period. The “quantity of power” is calculated as amps times hours = Ah.

For the technically interested I can mention that this does not quite give the same result. The battery has a higher capacity (Ah) if you discharge with little current during a longer period, than the other way around. USA and Europe have different standards to measure this and that’s why an American 100 Ah battery has less capacity than its European equivalent.

The ingenious amphour-meter is automatically integrating the current over time, meaning that it is adding up the used current during each specific time period, presenting it in Ah or percentage of the battery’s total capacity. If you, for instance, have used 30Ah out of a 100Ah battery, you have only 70% left. Voilà! Still not too difficult, right?!

 

How about the voltage then? During discharging, you should disregard from the voltage, since it is varying heavily depending on the load and hence is misleading. Many boats unfortunately only have a volt-meter so their owners try to get an indication of the battery status from its reading. If you wish to use a volt-meter, you need to switch off everything onboard first, letting the batteries rest for at least half an hour and then very carefully measure the voltage, something an analogue instrument is not capable in doing. So: Forget the voltage during discharging is my advice.

 

A prefessional battery installation: starter battery in black (to the right) and deep-cycle batteries in yellow (to the left). Foto: Marcus Åkesson

How many amphours (Ah) can you expect from your battery? It’s definitely not close to the figure shown on its casing, at least. Generally, the deeper you drain your battery, the shorter its life. Ordinary starting batteries are especially incapable in deep discharging (please observe that many so called “marine” batteries are just starting batteries in camouflage). Unfortunately, there is no clear distinction between these two types. Real service batteries are often called “traction batteries” and are of deep-cycle type. To allow for many deep cycles, the lead plates are extremely thick and sometimes rolled up into cylinders, placed in a robust housing. Ask which batteries are used for electrical trucks or golf-carts and you will be much closer to a good service battery for your boat than found in many chandleries.

Even with a good battery in your boat, I would not recommend to discharge it to more than 50%. I think this is a good compromise between benefit and lifetime. Please observe that an AGM-battery generally tolerates even less than open wet lead-acid batteries.

 

To understand the charging process, you need to know your charger. Your amphour-meter gives valuable information for this by showing voltage (V), current (A) and amphours (Ah). These, you need to monitor during the charging process.

 

Many simple chargers are of a type called “constant power”. When the voltage increases during the charging process, the current decreases at the same time, resulting in a very inefficient charging process, which means unnecessarily many engine hours. Check this next time you run your engine! Does the current (A) decrease linearly over time? If so, you should consider installing an external intelligent regulator, preferably together with a High Output Alternator (HOA).

 

The HOA makes sure that a maximum of current is delivered to the batteries and the regulator decides in what rate, allowing for shortest possible charging time without damaging the batteries. Unfortunately, not all engine manufacturers supply their engines with an HOA-kit with an external regulator. Yanmar does, for instance, but with Volvo-Penta you have to find an external supplier for second brackets, HOA and regulator (e.g. by Electromarine in Norway).

 

A High Output Alternator installed on separate brackets on a Volvo Penta D2-55 with external regulator on the wall after 1500 hours.

What is the difference between the HOA and an ordinary alternator? A standard-alternator can only generate the nominal current under very favourable conditions: it must be cold and run with maximum rpm’s. A small alternator mounted onto the hot engine in a cramped engine room rises in temperature very quickly, of course, both due its surrounding, but also due to its inner friction. Have you checked your alternator how much power it generates after five or ten minutes? Install an amphour-meter and I am sure you will get disappointed! Many alternators deliver no more than maybe 50% of its nominal rating. A true High Output Alternator, preferably in a so called “large case” with cooling fan, is able to deliver maximum current already at very low rpm’s and even while hot. Remember not to paint your alternator, especially not in any dark colour. Best is to leave the alternator unpainted allowing it to convey and radiate the heat from its housing.

 

The electronic external regulator, on the other hand, makes sure that maximum of current is lead to the batteries without damaging them. Charging is often done in three steps: “Bulk”, “Absorption” and “Float”.

The "brain": The external regulator

During “Bulk”, every possible last bit of power is stuffed into the batteries. On your amphour-meter, you will see how the current (A) is kept at its maximum during the entire “Bulk”-phase, thanks to the intelligent external regulator, despite the fact that voltage is increasing.

How much may you charge your batteries with, by the way? Open lead-acid batteries may be charged with 30% of its capacity (e.g. you may charge with 150A, if you have a battery bank of 500 Ah). GEL and AGM-batteries may take more: These can be charged with as much as 50% of its capacity (you may, in other words, charge a battery bank of 500 Ah with 250 A).

The Batteries are charged with 155A!

And for how long may you continue to charge your batteries with so much current? Well, either, until the batteries get too hot (and that’s why most regulators have a temperature sensor on the batteries), or until a certain pre-programmed voltage has been reached. When the voltage on the batteries (not on the alternator!) has reached the chosen value, the batteries cry out: “Thanks! That’s enough! Please take it easy, man!”. On your amphour-meter you can exactly follow when this is the case, namely around 14.4 – 14.8V . But remember never to set the value for GEL and AGM-batteries higher than to 14.1 – 14.4V 2.

The voltage to be set on your regulator is depends on the battery manufacturer’s recommendations as well as temperature. Generally, in a 12V system, decrease the voltage by 0.3V for each increase of 10°C or by 0.17V for each 10 F.

When the set voltage has been reached, the regulator changes over to the next phase, called “Absorption”. The batteries have by now been charged to approximately 80% of its capacity.

 

Do you remember our scenario? We discharged down to 50% and have now charged efficiently to approximately 80%. In other words, we have merely been able to use 30% of the battery’s capacity! Many cruisers and liveaboards stop charging now, after having run their engine for maybe 40 minutes. Without an amphour-meter, it would be difficult to know when charging starts to become less efficient. To charge the batteries up to 100% is just not practical on a cruising boat at anchor, not even with a diesel generator.

 

To stop charging at this point is certainly not good for the batteries, but that is unfortunately the fact for a poor deep-cycle battery that was unfortunate enough to to end up onboard a cruising boat. What a destiny! Since one only uses 30% of the battery’s capacity, you might understand why blue-water sailors often have large battery banks and invest in high quality deep-cycle batteries, which are much better to withstand this horrifying treatment.

 

To be nice to your batteries, you should give them a treat from time to time: at least once a month they should be allowed to become fully charged to 100% (thank goodness for shore power!).

 

So, let’s be just as nice to our batteries this time, as the manufacturers request from us. Instead of breaking off after the “Bulk-“phase, lets continue into the “Absorption”-phase. The regulator is now ensuring that the voltage does not rise any longer and is kept at the pre-set value. The current, however, which was stable at its maximum under “Bulk”, decreases now rapidly.

 

The higher the set voltage, the faster the charging is being performed during “Absorption”. Onboard our Hallberg-Rassy 40 Regina, we are charging with 14.8V at 25°C (80 F) during this phase. Higher Voltage is actually doing good to wet lead-acid batteries, since the rising hydrogen bubbles during gazing are mixing the acid. Just don’t forget to check the water regularly and top up whenever necessary.

The only disadvantage to charge with a somewhat higher voltage is that the lifespan of light bulbs decreases. Halogen bulbs have less problems with this, by the way. Before setting your regulator, always check with the battery manufacturer and also check what the maximum allowed voltage for your equipment is.

AGM or GEL-batteries may never gas and hence, as said above, never be charged above 14.1 – 14.4V. Charging this type of battery is somewhat slower during “Absorption”, thus.

 

The “Absorption”-phase is now to continue until the batteries are considered full. This may take up to 12 hours (maybe you have some understanding for the poor cruiser at anchor, who cuts off at 80%?). After “Absorption” the regulator goes over to “Float” (typically to 13.2V).

 

Some regulators switch from “Absorption” to “Float” after a pre-set time. Other regulators are integrated with the amphour-meter and consider the batteries as “full”, as soon as the current has gone below 2% of the capacity and may even automatically zero themselves at the same time, putting them back to “100% full”. But even if you don’t have such an integrated system, you can do it manually: If the charging current, for instance, goes below 10A and you have a 500Ah battery bank (i.e. 2% of the capacity) you can consider the batteries as full, irrespectively if your instrument shows “100%” or not.

 

How come would the Ah not necessarily read 100% when they’re full!? Well, an amphour-meter needs to be calibrated, you see, because the batteries have an efficiency coefficient. If you discharge your batteries with, say 95Ah, you might need 100Ah or more to charge them again. This coefficient needs to be set on your amphour-meter, otherwise it will show incorrect values after a few cycles only. Here, you need to do some trial-and-error, since the efficiency coefficient varies with the age of your batteries (the older the less efficient) and the charging current (the higher the current, the less efficient). You must hence find an approximation for your own boat so that the amphour-meter goes over to 100% exactly when the batteries get full. I suggest you start with a coefficient of 95% to start with, and rather choose a lower value than a higher, so you don’t fool yourself and believe the batteries are fuller than they actually are. If you are really sure that your batteries are full (e.g. after a day on shore power), you can zero your amphour-meter to 100% manually.

 

After a couple of charging cycles one gets a feel for how the batteries are being charged and can set the regulator accordingly. The usual values to programme your regulator with are the voltage at which the regulator should switch from “Bulk” to “Absorption”, the time it should stay in “Absorption” and the voltage it should provide under “Float”, so that you obtain a balanced system and the amphour-meter shows close to 0A.

 

I believe you agree with me that it is very comfortable to just sail from marina to marina, from one shore connections to the other and not having to bother about all this stuff. Life is so easy with power coming out of the plug! But freedom is found beyond shore power, at an anchorage not far from home or by sailing south into the sunset. With some basic knowledge about your amphour-meter, monitoring your batteries, your alternator and regulator, possibly also your solar panels, wind- or water-generators, you can stay out from civilisation for a long time and still be independent on power production.

 

That’s not too bad!

 

Regina, self-sufficient with power at anchor in Barbuda, Caribbean

[Careka]

Her er en oversikt over endel ladere og forskjellige batterityper , Denne viser at ikke alle ladere passer til alle batterier.

 

http://www.federalbatteries.com.au/files/charging.pdf

 

Strøm er og blir mye moro

[Komodo]

I forhold til den oversikten er ihvertfall 14 volt float mye. Men hva vet jeg, noen batterier tåler det kanskje allikevel?

[Careka]

Jeg vet at jeg skal ikke ha noe annet en gode vanlige bly batterier. og se til at de har nok vann.

og lade dem riktigt, de er lettest å ta vare på.

 

KISS.

[Careka]

Her er verdens størrste batteribank........... trur eg

 

The purpose of the 1.3 million batteries is to tame the wind, but only slightly, according to the AES Corporation of Arlington, Va., which developed both the wind farm, known as Laurel Mountain, and the battery project.

 

The installation is far too small to store a night's wind production and give it back during the day when it is needed, or to supply power when the wind farm is calm for more than a few minutes. Instead, AES says, the battery will be a shock absorber of sorts, making variations in wind energy production a little less jagged and the farm's output more useful to the grid.

 

The technology is young, and the finances are challenging. But the task of smoothing output, and the more ambitious one of storing many hours of electricity generated by wind production, seem likely to become ever more important as states require that a rising percentage of their electricity come from renewable sources.

 

The 13-state regional power grid that includes West Virginia, for example, has a capacity of 4,800 megawatts of electricity from the wind. But that number would grow eightfold if all of the states involved reached their renewable targets.

 

Power systems have always faced fluctuations in demand. As they incorporate more wind into the mix, they will have to cope with supply fluctuations as well.

 

Predicting wind output can be a challenge. "If you blow your forecast, you're in a heap of hurt," said one storage expert, David L. Hawkins, a senior consultant at KEMA, a consulting firm.

 

Other power sources, mostly natural gas plants, can be called on as replacements, but such plants take longer to ramp up - or ramp down - than a wind farm or a field of solar panels, a problem that is becoming more widely recognized across the country. This year, two big manufacturers of gas-fired power plants, Siemens and General Electric, promoted new models that could change output faster, but system operators say that even these may not be nimble enough.

 

"That's the challenge you have in running the power system," said Mark T. Osborn, an executive at Portland General Electric in Oregon who is working on a similar installation in the Pacific Northwest. "Storage has been thought about for years, but the costs have always been too high. Now when you're trying to integrate more renewable resources, storage becomes more necessary."

 

Already, in periods of low energy demand on windy nights, wind production is so strong that electricity prices on the grid can decline to zero or even go negative. When they are negative, grid operators bill wind suppliers to put power into the system.

 

In theory, the assumption would be that the operators of the batteries here would charge them at night and release the energy during peak periods in the daytime.

 

But the batteries are so small - somewhere between C and D batteries in size - that the wind farm, at full power, would fully charge them in about 15 minutes. Even at a peak demand time, the energy stored would only be worth a few hundred dollars.

Redigert 2.November.2011 av Careka (see edit history)