I will start with what we should all be able to agree on.
1) As a lead acid battery ages it loses AH capacity and other characteristics change.
2) Causes of this loss can be accelerated due to substandard charging, excessive depth of discharge, improper water levels (flooded batteries FLA) or extreme temperature conditions.
3) Substandard charging is as follows:
A) Insufficient or excessive ABSORB times
B) Improper ABSORB voltage
C) Excessive ABSORB currents
D) Excessive time spent in at less than 100% SOC (the lower SOC the worse)
4) The amount of current needed to maintain the battery's float status in a stable condition will increase with age (Stabilized Float Current SFC).
5) Hydrometer readings are effective in measuring a battery's State Of Charge (SOC) , however they are awkward at best and unavailable for sealed batteries. This is not a daily option.
6) It is generally accepted that the SFC is a valid measure of a battery's 100% State Of Charge (SOC).
That being said, using ENDAMPS as an indication of SOC assumes the health of the battery and IS NOT an accurate indicator of SOC. It IS NOT and indicator of battery health.
Using Stabilized Float Current (SFC) to control ABSORB time is (IMHO) the preferred way of charging a lead acid battery. It should extend battery life and yield daily indications of battery health.
QED
Barry - are you on Facebook ?
There is an Off Grid group there with 380 thousand members and some of them love to talk about lead acid batteries , and in detail.
They would probably be very receptive to this if you posted it there.
I have seen them discuss nuances of lead acid batteries before, especially when someone asks what kind of batteries they should get and as soon as someone says lithium, they jump on about lead acid being the best choice.
I find your post interesting, but since I have moved on from lead acid can't experiment or comment much.
Check out this group https://www.facebook.com/groups/2573968699280898
Larry
Larry, I will put you down as a maybe on the future of lead acid. :)
I feel confident that some of the other 2300 MidNite members still like lead acid.
I do appreciate the Facebook lead.
I have lead crystal gel type lead acid and haven't gotten rid of them because they perform so well. Their advantage and the reason I got them years ago was that they would work in cold weather and they did that even one winter when it got down to -40 F here. Good thing it warmed up a bit after that because they were struggling at those temps. But I never ran out of power from them shutting down.
Larry