Near as I can tell, an oversized alternator isn't going to provide quick
charging batteries. Lead acid batteries can't be quick charged without
damaging them. A charge rate of 20% to 25% of the total ampere-hour
rating of a flooded (not sealed) battery is recommended while sealed
batteries (gel, AGM) want a slower rate.

One can't just jam massive amounts of amperes into a lead acid battery
quickly unless you back it up with a massive number of volts -- more
than an auto alternator can put out, and if one did gerry-rig such a
charger the spew of sulfuric acid electrolyte when the battery boiled
over would put a real damper on the fun.

--
Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
KG6RCR