Three Things To Look For In Onboard Battery Chargers

Don’t let a dead battery ruin your day on the water

There’s nothing more disappointing than planning to spend a day on the water…only to find a dead battery. Most of the time, it’s our fault. Failing to properly maintain batteries lessens both their power and serviceable life. Onboard battery chargers keep those batteries ready whenever you are. Here’s what to look for.

A Marine-Grade Charger Built to Handle A Nasty Environment

ProMariner 43012 ProSport
Modern "smart" onboard battery chargers can distinguish between battery technologies, distribute charging amps for faster charging, and include protection against over-voltage and reverse polarity.Courtesy Amazon

Don’t be tempted with to save money with an automotive charger; they’re not de-signed for marine use. Instead, choose a quality, ignition-protected, marine-grade charger that meets American Boat & Yacht Council (ABYC) as well as UL standards. Ideally, that charger will be fully potted (encapsulated in resin) or feature other waterproof construction, resist corrosion and enable mounting in damp or possibly wet locations.

Proper Size And Output

Minn Kota MK 460 PC
Many smaller craft do not have a permanent AC electrical system. In this case, an extension cord can suffice. Or, consider adding a grounded AC power inlet that accepts the standard extension cord plug.Courtesy Amazon

An onboard battery charger should have an output equal to 10-percent or more of your boat’s battery capacity. Err on the higher side if you’re unsure. Better to have more output than you need than not enough.

Options For Mounting Locations

NOCO Genius GEN4
As your onboard battery charger will likely be tucked out of sight, consider the addition of a remote display to keep tabs on voltage and current charge cycle.Courtesy Amazon

When choosing a charger, keep in mind how its physical footprint will match up with your intended mounting location. Ideally that location will be cool, dry and have plenty of ventilation. (Choose a storage compartment? Avoid packing it full to ensure ventilation is adequate.) Close to the battery or battery bank is ideal to lessen voltage drop and reduce installation costs but avoid mounting directly adjacent or above as charging batteries give off gases that can be corrosive, even ex-plosive.