wrote:

On Jun 17, 12:02 am, Salomon Fringe wrote:

... Everybody I have spoken to has different (sometimes radically different)
AGM/gel experiences than yours, so I figure there must be something special
in your situation that makes these batteries really shine. I would like to
know what it is.


I wish you wouldn't lump AGMs and gels together. I've heard some
horror stories about gels and am still waiting to hear any about
AGMs. They are very different things.

My house bank is 2 Lifeline 8DL's that live in a well vented
compartment in the living area of the boat. For charging I have two
105 amp alternators and four 85 watt solar panels and a 25 amp, three
stage plug in battery charger set to flooded battery mode. I use an
Ample Power Energy Monitor/Controller. The solar is set to cut off at
13.5 volts. Normally the batteries simply live on the solar and every
once in a while when the voltage gets low (3-5 days typically in port
or daily on passage) I charge them up until their acceptance rate is
~1 amp when using the charger and ~13 amps when using the
alternators. They also get charged when we motor for an extended
period. That's it.


I'm not seeing anything out of the ordinary. Do notice that may not be
cycling your batteries very heavily. Also, your energy budget seems
quite low! How do you live aboard? Washer? Microwave? TV? Computer(s),
refrigerator/freezer?

...

I have a 24v setup and when I listened around and did the math two years
ago, I settled for Hawker full traction at half the price mentioned in the
Victron article. My second choice would have been semi traction based on
price and power. ...


Cool. How's it been working for you? What's your set-up and what
kind of service have you put them to?

--Tom.

I have 12x2v Hawker perfectplus traction batteries with one 100A bulk
charger, a 35A 3stage Victron 1500w inverter/charger and a Victron
Multiplus 24/3000w/70 4-stage charger and inverter. The batteries are in
a big zinc-lined steel battery case in the engine room with vent to the
outside. Additionally I have 6 semi-traction bats of 230Ah with their
own two chargers, I can switch from the tractions to this bank if
necessary but normally I use them just for lights and for the diesel
central heating (pump, burner) in winter (really :-) and yes I live
aboard) I charge them using a generator or shore current, rarely with
two 100A alternators (one per bank) on the main engine (with 3-stage
chargers),I really have to be moving a lot for that. About 60%/35%/5%.
As for the semi-tractions (which were more heavily used before I got the
traction batteries), they have performed well so far but at their age
(5yrs now) there's nothing special about it yet. Very little maintenance
actually, although I do check them. And with 2yrs on them I guess I
can't say a thing about the traction batteries yet except that they are
doing their job. Definitely more water use than the semis, but distilled
water is cheap and it takes about 5 minutes to check and add some once
per two-three weeks. Equalize them at 32 volt about once a month.

On Jun 17, 3:07*pm, Salomon Fringe wrote:
...
I'm not seeing anything out of the ordinary. Do notice that may not be
cycling your batteries very heavily. Also, your energy budget seems
quite low! How do you live aboard? Washer? Microwave? TV? Computer(s),
refrigerator/freezer?

I wish I could answer the cycling question better. My tactic is to get
a charger of some sort on the batteries when the voltage starts
dropping below ~11.9v when hit with a load. That load is typically ~8
amps when the fridge and freezer compressors pop on. I'm not sure how
much DOD that represents. At sea with the autopilot, lights,
computer, SSB, etc and the solar panels usually shaded, they do get a
deeply cycled for sure.

As for loads, well, I think my boat is pretty systems heavy but we
stop short of the washer/dryer and microwave. We do have two
computers a 12v refrigerator and a 12v freezer each w/their own
compressor, an electric auto-pilot, SSB, VHF, RADAR, GPSs, 1500 watt
inverter, instruments, a diesel heater (seldom used), an electric
windlass and lights (and probably some other stuff I'm forgetting).
We live on board full time and cruise extensively. Our boat is a 42'
catamaran.

Your set-up is in a whole other league, though. I'm kind of in awe.
I can see with a bank that size that cost must be a much more serious
factor. How do you like 24 volts?

-- Tom.

On Wednesday 18 June 2008 02:25, wrote:

On Jun 17, 3:07*pm, Salomon Fringe wrote:
I wish I could answer the cycling question better.

Yes I wish there were battery monitors that would integrate the number of
kWh taken from the battery over its lifespan, and do something smart with
every low and high % charge so people could finally really check and
compare performance.

My tactic is to get
a charger of some sort on the batteries when the voltage starts
dropping below ~11.9v when hit with a load. That load is typically ~8
amps when the fridge and freezer compressors pop on.
....

Does your battery monitor show % discharge of your bank? If so that might be
better than relying on voltage that changes depending on load.

As for loads, well, I think my boat is pretty systems heavy but we
stop short of the washer/dryer and microwave. We do have two
computers a 12v refrigerator and a 12v freezer each w/their own
compressor, an electric auto-pilot, SSB, VHF, RADAR, GPSs, 1500 watt
inverter, instruments, a diesel heater (seldom used), an electric
windlass and lights (and probably some other stuff I'm forgetting).
....
What does your1500w inverter power? I suppose the inverter will be the
heaviest load at possibly 120A @12v.

Your set-up is in a whole other league, though. I'm kind of in awe.
I can see with a bank that size that cost must be a much more serious
factor. How do you like 24 volts?

-- Tom.

Cost is always a factor, but as I said, I have never met anybody that had
his AGM (or gel) batteries outlive even their semi-traction batteries and I
didn't feel brave enough to try to be the first to prove it with my new
main bank...
WRT 24v - I have never used 12v so I can't compare. I can see things getting
cheaper and easier to install when halving all currents. Especially when
you have some distance to go.
Apart from all navigation equipment and some pumps everything here is just
running at 230v through the inverters. So outside the wheelhouse and the
engine room I actually don't see much 24v.

On Jun 18, 3:11*am, Salomon Fringe wrote:
... Does your battery monitor show % discharge of your bank? If so that might be
better than relying on voltage that changes depending on load.

It does, but it's funky. I've fiddled with the Peukert a fair bit
(now trying 1.150) and with the charge efficiency % (97). Still, it
always tells me the batteries are worn down long before the voltage is
weak and then it shows them fully charged while they're still
accepting current. And it periodically has a two's complement / over-
run thing that sends it off into huge negative numbers sounds the
alarms and requires a re-set... It is a nice volt/amp meter, it does
a good job of controlling the alternators and it does an adequate job
of controlling the solar, but it's not all that useful as a battery
gauge.

...
What does your1500w inverter power? I suppose the inverter will be the
heaviest load at possibly 120A @12v.

The computers mostly. I also have some battery powered tools that I
recharge with it and a dremel tool that I run off of it and when we've
got cell phones we charge them, too. Typically it is off.

We're basically a 12v DC boat. Sounds like you're on the other side
of the coin being mostly 230 AC (50 cycle, I presume). In theory,
your way should save a lot on wire and transmission losses.

Anyway, I'm very happy with my AGMs and I'm glad to hear that you're
happy with your tractor batteries. I think we'll all be happier yet
when nickel, lithium or maybe even fuel cells are affordable.

-- Tom.

wrote:
On Jun 18, 3:11 am, Salomon Fringe wrote:

It does, but it's funky. I've fiddled with the Peukert a fair bit
(now trying 1.150) and with the charge efficiency % (97). Still, it
always tells me the batteries are worn down long before the voltage is
weak and then it shows them fully charged while they're still
accepting current.

Seems like you have programmed it for too small a battery? You did check
the correct number of amp hours and if the monitor asks for a c/20, c/10
or c/5 value?
....
Anyway, I'm very happy with my AGMs and I'm glad to hear that you're
happy with your tractor batteries.

Not tractor, more like forklift ;-)

On Jun 18, 9:43*am, Salomon Fringe wrote:
...
Seems like you have programmed it for too small a battery? You did check
the correct number of amp hours and if the monitor asks for a c/20, c/10
or c/5 value?

Well I put in the nominal ah for the c/20 rate. But it could be that
the batteries are conservatively rated. The monitor manufacturers
suggest testing the batteries at a high rate and then a low rate to
get real numbers. I've avoided that as it can't be good for the
batteries to run them flat twice or more (a single test is likely to
have errors) and the numbers will change as the battery ages... All
in all that seems like a high price to pay to have a % remaining
number. I already know if the batteries are doing what I need.

Anyway, I'm very happy with my AGMs and I'm glad to hear that you're
happy with your tractor batteries. *

Not tractor, more like forklift ;-)

Oh darn "cruizhimers" strikes again. I knew it was one of the "T"
words... Sorry

-- Tom.