Seemingly AGM batteries prefer a particular charging sequence which is diferent to wet lead acid batts
That's a myth - which I personally busted...somewhere...in this unholy mother of a thread.
The difference between an AGM battery and an FLA (flooded lead-acid) battery is that one has fiberglass fabric between the lead plates. There's no magic nor mystery involved. You got your lead. You got your electrolyte. The fiberglass between the plates doesn't change anything other than keeping the stuff from sloshing, and keeping the electrolyte from stratifying into layers.
The charging routine for one, works for the other. In general, 3-stage battery chargers do a 14.4v/14.2v/13.6v bulk/absorb/float and that is, in general, the specified charge routine for the vast majority of
both AGM
and FLA batteries.
There are of course, a few exceptions. Here and there you'll find a manufacturer who specifies a slightly different routine for some particular battery.
But lead-acid batteries are not precise electronic components. They are sloppy chemistry devices. Sort of the St. Bernards of the electronics world. If you get any precision out of that goofy thing, then you got lucky.
So, even those few batteries which do have a slightly different routine specified, are going to be 99% okay on the same 14.4v/14.2v/13.6v routine that every other battery uses.
(GEL batteries *are* different, in that they do require a different routine. Specifically, slightly lower voltages on the stages - generally, 14.2v/13.8v/13.2v. And, unlike AGM or FLA, GELs are quite sensitive to going over the specified limits.)
There is a guy on the Internet, "
HandyBob" who promotes the idea that it is better to take a (non-sealed) flooded battery to a higher voltage, to get a more complete charge. He thinks 14.8v is proper. I totally agree with him. Iota battery chargers with their IQ/4 controller chip will do exactly that, so I suppose they agree too.
The main drawback, is that you may have to add water to the battery more frequently.
And you don't want to over-voltage any *sealed* battery (whether FLA or AGM) too much, because you might blow the pop-off valve and lose some water that you simply *cannot* replace.
- a car alternator does not provide that
In the boating world when you use AGM batteries you add a charge controller thats suited to an AGM battery between the alt and the batt
Or, a special voltage regulator, which will control the alternator in such a way as to provide a multi-stage charge. But the multi-stage charge will benefit either AGMs or FLAs equally well.
However, a typical automotive/marine alternator/voltage regulator system *will* eventually get a battery - either FLA or AGM - charged. It will hold the voltage of the "12v bus" at around 13.8v and eventually, the battery will absorb as much as it can - at 13.8v. Of course, if you could get the bus voltage up to 14.4v, then the battery (again, either FLA or AGM) will be more fully charged.
But the alternator system will get the battery (again, either FLA or AGM) to around 90% charged, which is normally good enough for an engine cranking battery, but for a deep cycle battery could take a very long time...
(And, any charge controller "suited to an AGM battery" is going to work equally well on an FLA battery - and vice versa.)
From my research it seems fundamentaly that an AGM requires a diferent charging scenario than other batteries
Nope.
Most AGMs and FLAs require essentially the same charging routine. Again, there are a few exceptions. In fact, some AGMs specify a different charge routine than
other AGMs.
This is one of the reasons why the phrase, "AGM specific" is marketing BS. If you have a charger with the perfect specs for AGM battery A, then what do you do when AGM battery B has different specs? They are both AGM after all...
IF *all* AGM batteries had exactly the same specs, and those specs were significantly different than the specs for FLAs, then "AGM specific" might not be the meaningless phrase that it is now.
But again, there *are* "GEL specific" chargers.
the average car is set up for wet lead acid batts-
No, the average car is setup for "cranking" batteries. They aren't setup to properly charge a "deep cycle" battery. *Any* deep cycle battery - FLA or AGM.
So to me selling an AGM battery for an auto aplication is wrong from the get go........
Not at all. Except for the fiberglass between the plates, they are the same as a flooded battery. What works for one, works for the other.
ie you need to add a specific AGM charger between the alt and the battery in order to correctly charge an AGM
Myth. Busted.
Solar and mains battery chargers for example have diferent setting for each battery type to insure long life and correct charging,
Some do. Most don't. They *all* have different settings for GELs though.
For example, a Morningstar SunSaver charge controller has a dip switch. One position is "AGM/FLA" (14.4/14.2v/13.6v) and the other position is "GEL" (14.2v/13.8v/13.2v).
A Samlex mains charger has exactly the same switch, except when on GEL it does the bulk voltage to 14.1v instead of 14.2v.
Again, for charging purposes, AGM and FLA are the same. They are both sloppy chemical devices and not very particular about what you feed them.
GELs are like women - they *are* particular.
I'm yet to see a car alternator have diferent settings
Alternators don't have settings. They are just generating devices controlled (rapidly switched on and off) by the voltage regulator. In the old days, voltage regulators could be opened up and a screw turned to adjust them. Not anymore - not since electronic voltage regulators.
But there are special regulators. Pretty common in marine use.
hence I don't think Optima or any AGM battery is suitable for a vehicular install, unless of course all the solar and mains charger manufacturers don't understand, or you add the specific AGM battery charger to the system
There is no such thing as AGM specific. And, as I've just noted, Morningstar (the largest solar charge controller manufacturer) charge controllers treat AGMs and FLAs as the same. Because they are. Samlex, and Iota (two of the larger mains charger manufacturers) do the same.
Marketing experts would like you to believe there are special chargers for AGMs, but there aren't. Even Optima's new Optima Branded mains charger says, "AGM specific" in the hype, but when you read the fine print, you see it says, "and also works for any other battery, such as flooded".
Now, having said all that...
Each and every battery manufacturer has their own specs for each and every battery. Most recommend 14.4v bulk, but some recommend 14.5v, or 14.6v. Some manufacturers recommend 14.6v for *this* battery, and 14.4v for *that* battery.
Which is mostly irrelevant. You got your lead plates sitting in an acid/water bath. You take it up to around "14 and a half" volts, and you are in the ballpark.
And "in the ballpark" is as close as you will ever get with such a sloppy goofy apparatus.