Marinco, Optima, West Marine and NOCO are popular brands of portable marine chargers. Most still incorporate alligator clamps, but many are shock- and waterproof, automatic, feature overload and polarity protection, and sparkfree hook-up. They, however, require you to individually charge every battery. Smart chargers can tell the difference between battery types, but others require manual settings for gel, lead-acid, and AGM batteries. AGMS require different voltages, but if a charger lacks the AGM setting, use the lead-acid setting. Promariner, Marinco, Dual Pro, Minn Kota and others offer fully automatic, three-stage onboard chargers that are vibration-, shockand waterproof, and designed to distinguish between Wet Cell, AGM and gel batteries to recharge and maintain them at the proper voltage. You’ll pay two to four times the cost of a portable charger for top plug-it-and-forgetit models with two-, threeand four-bank configurations, which afford you the time savings and convenience of charging multiple batteries at once.
ON BOARD: Integral chargers maximize convenience.