Landyacht did a terrific job detailing the ins and outs of how to charge a battery in a reasonable amount of time.
I'm going to offer a new nickname here, a buzzword if you may. There are apparently very few chargers (converters) that can be very effective boondocking charging the batteries.
The majority are PEDESTAL USE EXCLUSIVELY (PUE as an acronym)
The few that cut the mustard boondocking can be acronym buzzword BD converters.
PUE cannot hope to BD by itself without modifications and 2nd charger supplements.
SMART CHARGERS actually try to charge a battery correctly and generally end up somewhere in the ballpark
IGNORANT CHARGERS swear up and down they are smart but cannot count past ten without unzipping their pants.
DUMB CHARGERS do what they're told to do. Robots.