Where did you read AGM batteries must be charged at >14 volts?
Recharging is a game with all batteries. Depth of discharge and this can be expressed as percentage, versus total time needed to recharge. It is anything but a linear formula. Let's keep this limited to AGM.
Discharge 200 ampere hours from AGM. At 1n initial 10 ampere recharging rate it will take something in the area of 25-29 hours to obtain a charge rejection ratio of .50% amperes at full charge where the voltage of course has risen.
With unlimited time plus a guarantee the battery does not end up undercharged the limiting factor is time to sulfation - usually several days. The fuller the battery is the less likely it is to sulfate. A logarithmic scale in interpretation is neither needed nor desired. Problems arise when a recharge cycle takes, say, one week. The damage aggregates. It is cumulative over time.
But again, repetitive failures to fully recharge the battery is the thing to avoid. Being chemical, it too is a cumulative process, tempered by time spent at less than full recharge.
I must have missed something here. GENERATOR RUN TIME is the bugaboo for AGM. I trade max charging potential for time spent to fully recharge. It would be ideal to charge hard for two hours with a generator, then allow the rest of the day to attain point five percent full charge level via solar voltaic. Just make sure the point five percent happens - every day.
With long-term outage I can run the Frightening Harbor 2-cycle for eight hours on a tank of gas/oil at a very light load. This is why I seek those solar panels so I can play hide and go zap with the afternoon sun. As small as that buzzbox generator is, it still consumes fuel and makes noise for a living.
Here's a could be joke - two thousand amp hours of AGM. One half of one percent is 10-amps. Yeah yeah yeah, save it. The idea was presented. Any mention of lithium hexes your converter. Let's keep things organized - the world needs more orgas... ops I mean organs.
