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[drcampbell]

Yes, that's what I mean.

In a typical vehicle installation, there's an alternator capable of delivering 100-200 Amps and a battery capable of delivering ~500 cold-cranking Amps (at -18 degrees C) or ~1000 Amps at room temperature.

When fully discharged, That same battery can accept a charge current equal to about -1/3 of its rated cranking amps.
(the difference between quiescent voltage and charging voltage is about -1/3 the difference between quiescent voltage and cranking test voltage)

So the battery can accept a charging current equal to everything the alternator can deliver. Sort of like filling a swimming pool with a garden hose - the hose delivers whatever it can deliver, even though the reservoir could accept much more.

If you have massive (or many) batteries and a small alternator, it's the same thing. The alternator delivers whatever current it's capable of, and the batteries fill up with charge at that rate. (after deducting the hotel load)
(note that while adding battery capacity will cause them to reach 100% state-of-charge more slowly, you'll have the same number of Coulombs -- and the same probability of starting an engine -- in the batteries after any given length of charging time)

With a large alternator and small batteries, the voltage regulator would just dial back the alternator's output current to the optimum charging current needed by the battery.
This is the normal everyday operating condition with a fully-charged (or nearly-fully-charged) battery. A fully-charged 100 Amp-hour battery needs only a few Amps to maintain a full charge.

Keep in mind that none of this is steady-state. If you put 100 Amps into a fully-discharged battery, it doesn't stay fully discharged for long. It'll reach nominal terminal voltage pretty soon, at which point the voltage regulator dials back the alternator's output current. As you continue putting Coulombs into the battery, its quiescent voltage and charge impedance rise and it requires less charge current.