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**Daryl[_2_]**

On 3/22/2013 4:16 PM, wrote:
On Fri, 22 Mar 2013 15:16:58 -0600, Daryl
wrote:

On 3/22/2013 2:59 PM, Jim Wilkins wrote:
wrote in message
...

VERY common problem on "A Piece of Crap" UPS systems (as well as
some
cheaper ones) but when they split they don't leak.

The acid in an AGM battery is Absorbed in the Glass Mat.
jsw

No, the Glass Matt just keeps it from sloshing around. You break open
that case and the solution will leak out post haste.

And you have NEVER seen an accidental leaking of an AGM battery. Now
just admit it.

Those that can: Do. Those that can't: Teach

Daryl

They are also called "starved electrolyte" batteries - and even when
fractured they do not "leak". They are very similar in that respect to
the older "gell cell"

Totally different internal makeup between the two. Like many, you are
confusing the two and thinking the internal makeup is similar. They aren't.

The AGM must be kept upright since it does have free liquid in it. What
you see when it's case is bulged is from the Hydrogen and Oxygen being
unable to be vented due to excessive overcharging or the vent hole is
plugged up. Like the old style Lead Acid, when it vents, it burns off
the H2O breaking it up to Hydrogen and Oxygen Gasses. When you open one
up that has done this, what is left is the other parts of the liquid in
the form of solids or actually, powder. The Plates are still lead.
This one, like the unsealed lead acids can form Sulphates on the plates
which shorten the life of the battery because of running them below 50%.
The good news is the desulphators work offered with low amperage may
recover them to almost new condition when that happens.

When you need a battery that cannot be kept in an upright position, you
choose the Gel Cel. In this battery, the Sulfuric Acid is mixed with
Silica Fume and it makes it into a gel. The Plates are of a Calcium
makeup and are not lead. People confuse the AGM with the Gel Cel all
the time. If you want the best, longest lasting UPS battery, get rid of
the AGM and go with the Gel Cel. They cost more but last much longer.