What is AGM, and what makes AGM technology better
Absorbed Glass Mat batteries are constructed differently than the
traditional flooded battery. This write up covers mainly the Concorde
AGM's, but also applies to most other brands of deep cycle AGM batteries.
In AGM batteries (also called starved electrolyte), there is a thin
ultra-fine fiberglass mat sandwiched between the plates that are
saturated to about 95% of what they can hold. This mat is then packed
in between the plates and slightly compressed, then welded/soldered in
place. Because the plates and mats are packed fairly tight, they are
almost immune to vibration.
AGM (Absorbed Glass Mat) sealed battery technology was originally
invented in 1980, and developed and introduced in 1985 for military
aircraft where power, weight, safety, and reliability were paramount
considerations. The Concorde is a VRSLAB (Valve Regulated Sealed
Lead-Acid Battery). Sometimes referred to as VRLA (Valve Regulated
Lead-Acid). Several manufacturers now produce AGM batteries, but
Concorde was the first to develop the technology for commercial
quantities.
An important thing about AGM - Just because a battery is AGM does NOT
make it a deep cycle battery. Several companies, such as Optima, have
adopted AGM for starting batteries and other non-deep cycle
applications. Those still have the advantages of AGM, but are not deep
cycle.
Cutaway of Concorde AGM Deep Cycle BatteryThe Sun Extender batteries
are essentially the same construction as the Concorde Lifeline,
Chairman, and other Concorde AGM batteries. The major difference is
that the Sun-Extender batteries have bolt-on terminals instead of the
common post type. We feel that bolt on terminals give a much more
reliable connection. We also stock most. Chairman batteries and some
LifeLine batteries.
Efficiency:
This comparison is important, and is critical for high charge or
discharge rate applications. Internal resistance of a battery denotes
its overall charge/discharge efficiency, its ability to deliver high
currents without significant drops in voltage, and is a measure of
the quality of the components and construction.
Internal resistance in NiCad and NiFe batteries is approximately 40%,
i.e., you need to charge them to 140% of its rated capacity to have it
fully charged. For standard flooded Lead-Acid batteries, internal
resistance is usually around 10% to 15% for a new battery, and can be
as high as 25%+ for older batteries. Internal resistance
which is the charging current lost to gassing, or breaking up of
water. Gel acid batteries are better at approximately 16% internal
resistance and require only roughly 116% of rated capacity to be fully
charged. Concorde Advanced AGM has the lowest internal resistance of
any battery manufactured - only 2 percent. In solar electric systems,
this is the same as getting an extra 10 to 15% our of your panels.
This allows Concorde batteries to be charged much faster if needed and
also to deliver higher power when required. Owners using high output
alternators, operating inverter banks, or relying on solar panels can
benefit significantly when using Concorde Advanced AGM batteries with
their equipment. Concorde AGM's are more efficient.
Heat: Better efficiency also means much less heat is developed in the
batteries - any current that does not actually go to charging a
battery turns into heat. That is why some batteries, especially older
flooded batteries (and even some non-deep cycle AGM), can get very
warm or even hot. In extreme cases you can get " thermal runaway",
which can be dangerous.
Concorde batteries far exceed the US Coast Guard test for thermal
runaway: These MW-SPEC (Military Specification) tests involve fully
charging a battery, heating it to over 130 degrees (Potential Thermal
Runaway Conditions) and then overcharging the battery to simulate a
shorted cell. (16V for a 12V battery).
Concorde AGM batteries are NOT a gelled electrolyte. It is considered
a "Recombinant Gas Absorbed Electrolyte" battery. This cuts water loss
by up to 98%. Loss of charge due to self-discharge is 3 to 10 times
better than with conventional gelled, and 5 to 50 times less than with
flooded batteries. The gasses recombine almost 100% within the
battery, reducing Hydrogen emissions to a level far below most battery
types, and less than half the lower explosive limit for Hydrogen. In
addition, they do not have the charge and discharge current
limitations that most gelled batteries have.
Concorde AGM battery technology has continued to develop and offer
improvements over other sealed battery technologies. AGM technology
has become the next step in the evolution of both starting and deep
cycle sealed batteries for marine, RV, and aviation applications.
These are the same type of batteries that the Navy and Air Force used
in Desert Storm in their F-18 and F118B "stealth", and in the Marine
Corps "HumVees".. This "next generation" technology delivers increased
safety, performance, and service life over all other existing sealed
battery types, including gel technology. All Concorde AGM batteries
carry a one-year full warranty - most gelled cells carry only a 90-day
warranty.
All AGM batteries, such as Concorde, have much better resistance to
vibration and shock due to their construction than most flooded
batteries. The plates are packed in with the glass mat, reducing plate
movement and vibration to nearly zero. In addition, because the glass
mats are not totally saturated and the liquid does not expand to cause
plate and case damage, AGM batteries can withstand freezing.
Concorde AGM batteries meet MIL-SPEC B8565J and FAR 23.1353,
25.1353©, 27.1353, 29.1353(3), 25.853(a). All Concorde AGM batteries
are shippable without restriction by any means of transportation,
including air. Hazardous labeling is not required.
In AGM sealed batteries, the acid is absorbed between the plates and
immobilized by a very fine fiberglass mat. No silica gel, as is used
in gelled, is necessary. This glass mat absorbs and immobilizes the
acid while still keeping the acid available to the plates. This allows
a fast reaction between acid and plate material. Even if the battery
is broken, no electrolyte will be spilled.
The AGM battery has an extremely low internal electrical resistance.
This, combined with faster acid migration, allows the AGM batteries to
deliver and absorb higher rates of amperage than any other sealed
batteries during discharging and charging. In addition, AGM technology
batteries can be charged at normal flooded lead-acid regulated
charging voltages, therefore, it is not necessary to recalibrate
charging systems or purchase special chargers. Concorde AGM batteries
can be bulk charged at high rates without damage - up to 10 times as
fast as most gelled cells, and 4 times as fast as flooded batteries.
Where you cannot have fumes or hydrogen, such as in poorly ventilated
areas.
Where resistance to shock and vibration is important.
Where spilled acid from leaking, tipped, or broken batteries cannot be
tolerated.
When installed in a location where maintenance would be difficult or
expensive, such as remote communications sites.
Anyplace where you need a reliable totally sealed battery for safety
or environmental reasons - wheelchairs, medical standby power, inside
RV's, computer room UPS systems, or in enclosed spaces in boats.
Stephen 77fc35
--- In
WanderlodgeForum@yahoogroups.com, Tom Warner
wrote:
>
> No one questions whether AGM batteries are good or not. but most
> coach owners dont use them often enough to justify buying them when
> flooded deep cycles work fine for our use. I only had 4 interstate
> deep cycles in my FC35 and never ran out of power even using the
> satellite system, LP furnaces and microwave etc, Still plenty of
> power to start the engine the next day. At $58 each, for me its
> difficult to justify buying AGM batteries. Whats the advantage? There
> is still the problem of being very careful in over charging them.
>
> I just replaced 6 brand new Optima batteries that were installed in
> my PT when I bought it ( $180 each here in advance auto) with new
> interstate deep cycles. they are easy to maintain in a PT (a little
> harder in a FC) and provide plenty of power for my use.
>
> tom warner
> vernon center,ny
> 1985 PT 40
>
> At 11:37 PM 11/28/2006, you wrote:
> >That link was last updated in 2002 I would tend to think that a few
> >things have changed since then ie chargers, battery construction
> >AGM Batteries are a viable alternative to interstate flooded cell
> >batteries including who produced them Interstae is a marketing company
> >that jobs batteries out to different manufacturers and sells thenm
> >under the interstate label
> >Stephen 77fc35
> >
> >
> >--- In WanderlodgeForum@yahoogroups.com, Tom Warner wrote:
> > >
> > > Curt before you decide on what batteries you get you might want to
> > > read the poop sheets especially this
> > > one. http://www.phrannie.org/battery.html Unless you have an
> > > excellent charging system that does not exceed 14.1 volts you may
> > > have problems with AGM batteries.
> > >
> > > When I bought my PT 40 there were 7 new Optima batteries in it, 6
> > > where the starting/house batteries were and one for the generator.
> > > They were terrible for my aplication and are now sitting on my
garage
> > > floor and new Interstate deep cycles in place of the 6. I still kept
> > > the Optima in the generator compartment.
> > >
> > > I get Interstate deep cycle 6 VDC golf cart batteries for $58 each ,
> > > they work fine.
> > >
> > > tom warner
> > > vernon center,ny
> > > 1985 PT 40
> > >
> > > At 03:59 PM 11/28/2006, you wrote:
> > > >Anyone have experience with the Fullriver FR-GC2 batteries?
> > > >
> > > >You can review the Fullriver Battery line at
> > > >http://www.dcbattery.com/fullriver.html
> > > >
> > > >I got this quote from dcbattery...$982.33 for 6 batteries,
total which
> > > >includes delivery costs to your address if paid via Paypal.
> > > >
> > > >An additional discount is offered if prepaid via check. $953.72
total
> > > >which includes delivery costs to your address.
> > > >
> > > >--
> > > >Curt Sprenger
> > > >1987 PT38 8V92 "MacAttack Racing"
> > > >Anaheim Hills, Calif.
> > >
> >
> >
> >
> >
> >
> >Yahoo! Groups Links
> >
> >
> >
>