What really matters is looking at charging from the battery's POV. A while ago, I ran across the term 'Amp hour law' in relation to charging batteries.
As I understand it, there is an optimal charge current that gives a balance between speed and battery life. The basis is that this charging current should equal the Amps missing from the bank throughout charging. Amps will always taper.
When we discuss charging from the charger's POV, we need to know our charging goal; speed v.s. battery life.
I am not aware of a charger that KNOWS the missing amps, so we don't know if we are charging fast or slow. Enter the battery 'fuel gauge'.
Battery mfgrs give us a clue when they publish Volt and Amp limits. Some also publish temperature charts for Voltage regulation. So long as we stay close to these limits we should be safe.
Charger mfgrs use all sorts of magic smoke algorithms and their manuals are full of legalese and marketing mumble-speak. Do they do what the battery wants? Some here prefer to use manual controls.
Try to focus on what the battery wants. I believe this is what Mex is doing. Perhaps this is saturation charging.
IMHO, YMMV, and HTH;
John
