Battery management

I still would have gone AGM...that is the perfect charging profile for them....or at least at the bulk phase. FLAs will fry at that rate...make sure in the FLA setting you are getting proper charge profiles for those batteries or you will be going through this again in 2 years.

Baker said:

I still would have gone AGM...that is the perfect charging profile for them....or at least at the bulk phase.

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Most of the older Trace Engineering units had two settings:

GEL = 14.1V Absorption & 13.5V Float
Flooded = 14.5V Absorption & 13.4V Float


They also had a fixed 90 minute absorption which in most applications usually pretty inadequate before dropping to float.


At 14.5V & 13.4V it can work for some AGM's but is far from perfect for others.

AGM Voltages:

Lifeline AGM = 14.4V & 13.4V
Odyssey TPPL AGM = 14.7V & 13.6V
Firefly AGM =14.4V & 13.2V
Mastervolt AGM = 14.4V & 13.2V
Full River AGM = 14.7V & 13.7V
Rolls AGM = 14.7V & 13.7V
East Penn/Deka = 14.6V & 13.6V
US Battery AGM = 14.4V & 13.4V
Trojan AGM = 14.4V & 13.5V

Trojan Flooded batteries:

Trojan Flooded = 14.8V & 13.2V

Each battery maker has slightly different suggestions for absorption & float voltage.

This is why for optimal cycle life chargers with adjustable absorption, float, temp compensation and an adjustable absorption duration make better choices than simple two or three choice dip switch chargers...

A remote watering system with auto off float caps will allow you to keep FA batteries topped off without bending over and without even seeing the batteries.

Just put the hose in a gallon of distilled water and pump to automatically fill to the proper level all the cells at once, takes about 10 min once a month.

Not a bunch of cash out for the tubing and hand pump kits including the battery caps. I spent around a hundred bucks adding it to my 8 GC battery house bank.

No reason not to have one on every boat as far as I can tell, your batteries will last longer and happier lives.

Scottee

Neither my house or starting batteries require water monthly. I'd guess a few CCs per month could be added but the question seems how often does a good battery with a decent charging system need water? Guess it varies.

Let me put on my lecturer's hat and explain the difference between "marine" batteries and others, as well as "marine" alternators and others. Non geeks can skip to the next post.

In terms of batteries, I take "marine" to mean deep cycle house use which requires a battery to handle hundreds of discharge/charge cycles but at moderate amp output over long term- maybe 10 amps. Some have used "marine" to refer to batteries with better mechanical properties to keep the plates from banging around while pounding in their cigarette boat, but I don't really believe there is any difference anymore, if there ever was.

A starting battery has lots of of thin plates which let it put out a lot of current for a few seconds- the CCA rating. But heavy discharge and recharge over hundreds of cycles will cause those plates to look like swiss cheese over time due to sulfation plate losses.

So deep cycle batteries have heavier plates and golf cart batteries at least, have more clearance under the plates to accumulate the sulfate that sloughs off. They also have more headroom for electrolyte over the plates to allow for some electrolyte losses in between waterings. That is why a GC battery is taller than a Group 24,27,31.

Most, maybe nearly all Group 24, 27, 31 and 8D batteries are not built like this and are not true deep cycle no matter what they say. The only flooded cell true deep cycle batteries that you can count on are golf cart batteries.

The foregoing does not apply to AGMs and as best I can tell, there are no real differences in starting and deep cycle AGMs, whether they are golf cart size or otherwise. So if you have to have 12V batteries, use AGMs.

Switching to alternators:

There are no marine alternators, only OEM internally regulated alternators and high output, externally regulated alternators. Cummins puts a Delco on their engines, Yanmar uses Hitachi. Those OEM alternators are regulated to a fixed voltage, about 13.5 V which is ok for minimal recharging of the few amp hours used for starting, but will not recharge a 50% discharged marine battery very fast.

To charge at high rates from a deep discharge you need an external, three stage regulator that will increase the alternator's output voltage up to 14.5 or so to push out the amps, but drop back to the float voltage of about 13.5 V when the battery is charged.

Some say that you can take your OEM alternator to an auto electric shop and have them open it up and bring out the field wire to an external terminal so you can connect to an external regulator. That will work, for a while.

High output alternators, like those made by Balmar, Ample Power, Powerline and even Leece-Neville have heavier windings, heavier diodes and a better fan and cooling to handle the long term high amperage output. Trying to make an OEM alternator that was designed to put out a few amps for a few minutes run at near 100% for hours at a time is destined to fail.

But from the perspective of a long term, live aboard sailor, who switched to power, most trawler owners don't need a high output alternator. We run our propulsion engine to get from place to place, unlike a sailboat, and that run if long enough will recharge the batteries even with the OEM alternator. Also many trawlers have gensets and a high amperage inverter/charger that will recharge the batteries quickly at anchor.

But if you don't have those capabilities and you anchor out in one place for more than a few days, consider a high output, externally regulated alternator.

David

CMS said:

This is why for optimal cycle life chargers with adjustable absorption, float, temp compensation and an adjustable absorption duration make better choices than simple two or three choice dip switch chargers...

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Yep...I just installed a Magnum Energy Inverter/Charger with their BMK and remote panel running off of 5 Odyssey AGMs.....I am diggin it so far.

sunchaser said:

Scottee

Neither my house or starting batteries require water monthly. I'd guess a few CCs per month could be added but the question seems how often does a good battery with a decent charging system need water? Guess it varies.

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I have a solar system and it is solely responsible for the day to day charging of my house banks as well as engine, gen-set and thruster batteries by way of 3 Belmar 12v to 12v DC chargers working off the house batts.. It works great and always maintains 100% charge as shown by my SOC gauges.

However as it takes only a few mins. to grab a jug of distilled water every months or so and give a few squeezes until the pump gets hard indicating full batteries so why not? I am sure I don't NEED to fill them once a month but I just top them off as part of my monthly checks. My batteries are in boxs down below and not real easy to get to but then again I don't have to.


http://www.janwp.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=JANWP&Category_Code=JWPCHART


I was always puzzled by folks that buy expensive AGM or Gell batteries stating that they are too hard to water but don't consider an inexpensive and easy to use watering system. The advantage of an inexpensive, rugged and forgiving set of good old heavy duty golf-cart 6 volt batteries are hard to beat and can be found anywhere.




Battery Watering Systems, Marine Dock Products, Solar Dock Lights: OFF GRID Application- 6V L16 8D HUP ROLLS

Gordon J said:

George, I am having the batteries delivered by Fort Lauderdale battery. They are charging 500 for gels and $550 for AGM.

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AGM's easy for that price.