another source for agm batteries

red31 wrote:
Lifline manual

battery's SoC will gradually "walk down" as it is cycled leading to premature failure. Therefore, it is important to verify that the battery is not being undercharged.

Is not that the same as saying fully charge?

I don't believe that is the definition of a cycle as depicted in life-cycle charts. A cycle must end with some type of completion criteria. In fact life-cycle only means the point in time when the battery has 80% of its original capacity.

Here is the complete quote:

Lifeline 5.4 wrote:
Note that this formula is approximate and the full charge state should be verified using the criteria given above (current drops below 0.5% of rated capacity). If the recharge does not
return 102% to 110% of the discharged capacity, the battery’s state of charge will gradually “walk down” as it is cycled leading to premature failure. Therefore, it is important to verify that
the battery is not being undercharged.

A cycle will meet the criteria of "(charge) current drops below 0.5% of rated capacity" and/or "return 102% to 110% of the discharged capacity". When you complete these criteria, you have a cycle.

I have no idea how to correlate partial use/recharge, or charge while in use to life cycle charts.

A lot depends on how long the sulphate remains on the plate(s) and therefor, needs a special recovery charge to release old, stubborn S atoms as described in 5.5. Lifeline says to observe a loss of capacity AFTER a 5.4 charge(cycle) as the signal to do a 5.5.

HTH;
John