wrote:
On Jun 15, 1:23 pm, Salomon Fringe wrote:
...

Yes I actually have the printed version of that doc, but I don't think
there is even a hint of being able to use a AGM for 8+ years while
deep-cycling... ?


Well, I don't think I said that. What I was trying to say is that the
author doesn't seem to have had any trouble coming up with published
data. For instance he notes that deep cycle flooded cells ("semi-
traction") get 350 cycles at 60% DOD (which is deep cycling) while
AGMs get 650-800 depending on construction and chemistry. Service
life depends on how you use them but the AGMs look much better than
the semi-traction batteries for deep cycle use. His service life
numbers suggest that some AGMs will be expected to last 10 years.
AGMs have only been popular in marine use for less than a decade so it
may be hard to get real numbers. My experience has been fantastic.
YMMV... I think some of the very negative responses in the "Dutch
magazine" (if they exist, got a citation?) might have been for gel
cels. AGMs are not gel cells and linking them is bogus (or maybe even
dishonest). AGMs have really good cycling numbers and they are
published and you've even posted a link to them. So the Sterling
guy's conclusion that you should avoid AGMs because they have "poor
cycling numbers" is hard to figure. The rest of his arguments seem to
be based on straw men and thin air, too. Who is this guy?

Although it's a little off topic http://www.proboat-digital.com/proboat/20080203/
is interesting and has some insight into usage issues.

...

Err, I was hoping you would have the links handy... ;-)


I was hoping you'd do your own. If you can't google I'll do it for
you, but last time I looked both Full River and Lifeline (Concord) had
graphs and spec sheets on-line for their AGMs. You may have to plot
data from your favorite flooded deep cycle battery for comparison but
if the flooded guys have nothing to hide their data will be on-line,
too... ;-)

I'm not trying to sell AGMs. There are good reasons that they don't
use them in golf carts, for instance. But the guy at Sterling seems
to have decided that he hates AGMs and then gone off to figure out
why.

--Tom.


Well the author of the Victron article really did a good job and I have
used his info extensively but I did realize that Victron sells gel and
AGM but nothing else in terms of batteries so I assumed a slight nudge
towards their product line in the numbers. Also his pricing info in the
comparison was way off from what I found, e.g. full traction was just
50% of the price he stated.
The amount of active material in any lead acid battery, be it flooded
gel or AGM is what makes the battery survive longer for cycling, and so
comparing the most expensive thick-plate AGM with standard flooded cells
does not make sense. We should compare AGM and flooded batteries that
have equal weight (lead) or, for a different comparison, equal price. I
think that in real life, a flooded cell will hugely outperform the AGM
for cycling use because you can equalize a flooded cell to refresh weak
cells, because you cannot monitor the temperature of each battery (let
alone every cell) while charging which means guaranteed overcharging of
some batteries/cells - destroying your typical AGM cell. Of course it is
cheaper, too.

Returning to the Victron article, even with my suspicions about the
author towards his own product line, what I distilled from the article
was that tubular plate traction batteries are the best deal for serious
cycling, not gel or AGM. I did my research two years ago so things may
have changed but I don't think the numbers can have changed that much.

I would like to know from people who have REALLY deepcycled their AGM's
500 times (anybody counting?) and are still using them. If these exist I
believe that you will find they paid as much for their AGMS as they
would have for equivalent capacity traction - which would last at least
twice as long.

wrote:


Here's a fun little practical application demonstration that Salomon can try for
himself:

Take a group 31 flooded deep cycle battery of whatever brand you think is the
best, and any group 31 AGM battery off the shelf regardless of brand. Attach a
12 volt headlamp to each and let them sit with the headlight burning until it no
longer glows at all, indicating the batteries are flat.

Now, wait 30 days, and THEN recharge both batteries using whatever method is
recommended by the manufacturer.

After charging, load test both batteries. You'l find the flooded battery is now
a heavy piece of junk, but the AGM performs pretty much as it did before this
torture test.

Good. Now you do the following experiment. Tkake the same group of deep
cycle batteries and AGM batteries and put them on a charger at 15V.

Wait just one week, and THEN test both batteries. You'l find the AGM
battery is now a heavy piece of junk, but the flooded battery performs
pretty much as it did before this torture test.

After you did this test, stop and think what which of these two torture
tests would be the more likely that a battery installed in a cruising
boat will ever have to face.

What is your conclusion now?

Brian Whatcott wrote in
:

I wonder if, could it
be? that reclaimed oil makes the same nose?
If so, count me in!

Brian W


Some people claim they can smell french fries, but I can't. The oil is
very clean burning. Whatever liquids are attached to the oil we don't
separate them. There's no water in the oil as it all boils off in the
deep fat fryers that sit there for hours. We filter down to .5 microns,
which will easily flow through the injection nozzles. I've never had a
clog from it in the years I've used it that way.

The oil, itself, still has that "burned" smell of used deep fat fryer
oil. There's a mix of Canola and other vegetable oils in what we get.
It doesn't seem to matter from batch to batch where it came from, as long
as it will burn at 22:1 compression we're fine.

One of the engines we're supplying had 220K miles on it and had an
overhaul after about 80K on the oil. Nothing unusual was seen in the
engine, to the mechanic's amazement. He'd been reading oil company
propaganda saying it would destroy the engine, which is simply not true.
Their reason for the lie is fairly obvious. There was no unusual coking,
stuck rings, etc. from burning it. It burns very clean and you have to
really work hard to get it to smoke on hard acceleration, unlike dino
fuel oils.

Burning slower, and it does burn much slower, there's much less knocking,
which has got to be easier on all the pressure induced stresses on
pistons, bearings, rods, crank. There's not as much power so there's not
as much stress. My '83 300TD wagon is on 247K miles and still runs fine,
except for top gear on the transmission shifting a little soft these days
before the worn clutches finally hold solid, but that has to be expected
at a quarter million miles...(c;

Sure lets you keep your wallet fuller of those faux Fed banknotes we pass
off as "money" on the world.

.....oh, back on topic....wetcell batteries are best....

"Roger Long" wrote in
:

are willing to put up with crawling around on top of them sucking
acid out of them with a hydrometer and putting distilled water back in
to them to repair the damage you have done to them

What??!! Where the hell did THIS come from? They don't manufacture excess
acid! Overcharging does NOT produce more acid....only converts water into
hydrogen and oxygen.

Wayne.B wrote:

On Sun, 15 Jun 2008 15:20:55 -0700 (PDT), "
wrote:


His service life
numbers suggest that some AGMs will be expected to last 10 years.
AGMs have only been popular in marine use for less than a decade so it
may be hard to get real numbers. My experience has been fantastic.


I have heard the same from others whom I respect. I will probably
convert one of my house banks to AGMs in the future.

I hope you were also thinking of adding another charger, since if your
other bank is not AGM you will need it.

Roger Long wrote:

This discussion is going the way many do here and in other venues. The
perspective makes a huge difference.

...

One thing that influences my system driven decision to have AGM's is my less
than optimum battery box location. Checking wet cells with my face just a
few inches above the batteries after squirming headfirst into the quarter
berth and sticking my head in a small hatch from which it would take a while
to extract myself holds no appeal, goggles or no goggles. My electrical
consumption profile does not require that I be able to recharge at high
rates.


Thanks for pointing out your situation. Considering that I would also
have bought AGM.

On Mon, 16 Jun 2008 07:38:14 -0400, "Roger Long"
wrote:

After hearing what my friend went through after his acid shower, I wouldn't
put wet cells in my sailboat for anything or any cost savings.

What were the circumstances of your friends accident ?

Salomon Fringe wrote in
:

wrote:


Here's a fun little practical application demonstration that Salomon
can try for himself:

Take a group 31 flooded deep cycle battery of whatever brand you
think is the best, and any group 31 AGM battery off the shelf
regardless of brand. Attach a 12 volt headlamp to each and let them
sit with the headlight burning until it no longer glows at all,
indicating the batteries are flat.

Now, wait 30 days, and THEN recharge both batteries using whatever
method is recommended by the manufacturer.

After charging, load test both batteries. You'l find the flooded
battery is now a heavy piece of junk, but the AGM performs pretty
much as it did before this torture test.

Good. Now you do the following experiment. Tkake the same group of
deep cycle batteries and AGM batteries and put them on a charger at
15V.

Wait just one week, and THEN test both batteries. You'l find the AGM
battery is now a heavy piece of junk, but the flooded battery performs
pretty much as it did before this torture test.

After you did this test, stop and think what which of these two
torture tests would be the more likely that a battery installed in a
cruising boat will ever have to face.

What is your conclusion now?

Perhaps your conclusion should be that you should have invested in a good
charge controller to make sure that you don't charge at 15V. If you're
investing in AGMs, you should invest in the rest of the necessary
components also.

You should also learn that you shouldn't deep cycle any batteries. I try
not to have mine drop below 12.3V and typically keep them at 12.5V and
above.

-- Geoff
www.GeoffSchultz.org

"Roger Long" wrote in
:

I meant sucking electrolyte out to read the hydrometer. Sure it goes
right back in but, if you could see my installation, you'd know why
checking them doesn't have much appeal.

--
Roger Long





Whew! Thanks! I had visions of boaters sucking out the over supply of
acid and replacing it with water....(c;

I used to have to lay on my belly with my eyeballs 3" from the top of the
cells on the Endeavour 35 sloop's starting battery Geoffrey used to
have...under the quarterberth mattress in a little well. How awful.

wrote:

On Mon, 16 Jun 2008 13:06:47 +0200, Salomon Fringe
wrote:


wrote:


Here's a fun little practical application demonstration that Salomon can try for
himself:

Take a group 31 flooded deep cycle battery of whatever brand you think is the
best, and any group 31 AGM battery off the shelf regardless of brand. Attach a
12 volt headlamp to each and let them sit with the headlight burning until it no
longer glows at all, indicating the batteries are flat.

Now, wait 30 days, and THEN recharge both batteries using whatever method is
recommended by the manufacturer.

After charging, load test both batteries. You'l find the flooded battery is now
a heavy piece of junk, but the AGM performs pretty much as it did before this
torture test.

Good. Now you do the following experiment. Tkake the same group of deep
cycle batteries and AGM batteries and put them on a charger at 15V.

Wait just one week, and THEN test both batteries. You'l find the AGM
battery is now a heavy piece of junk, but the flooded battery performs
pretty much as it did before this torture test.

After you did this test, stop and think what which of these two torture
tests would be the more likely that a battery installed in a cruising
boat will ever have to face.

What is your conclusion now?


Most charging systenms have regulators, and there is no reason why you
would charge an AGM at 15 volts unless you were an incompetent
idiot...

Oh, wait...

nevermind.


Why is draining batteries empty with a headlamp and then leaving them
like that for a month more competent than charging an AGM at 15V?