Do AGM's charge quicker?

BFL13 wrote:
The battery's voltage continues to climb all the way through both stages.

That's the head-scratching tricky part ... what is the "battery's voltage"?

With a high quality and powerful enough battery charger - during charging at either the constant current stage or constant voltage stage (... and of course using a charger with no voltage sag due to it's current delivery capacity) - the "battery's voltage" is the voltage on the battery's terminals that has been forced by the charger ... and hench is that which is showing on the charger's meter and matching what you set the charger at.

To me however ... the "battery's voltage" is what it reads several minutes after you have removed it from the charger (to get rid of surface charge).

So I guess what has been talked mostly around so much in these forums is: If a battery's at-rest terminal voltage after somehow/someway charging it long enough over the years with "whatever" charging voltages (like I have) is still showing at it's original as-new design value - that does NOT MEAN that it's full capacity is still present.

IAW, a battery's terminal voltage reading may indicate full charge at present capacity, but not full charge at it's original capacity when new.

So ... I've been slowly ruining my RV batteries by fully charging them (per at-rest terminal voltage readings) with too-low charging voltages time and time again over the years. :(