- by Bryan Veldboom - updated on 4/8/2021
The sun is out, the water is clear and you’re ready for a pleasant weekend on the water. But when you go out to your boat, you find out you've got a dead battery on your hands. You can avoid frustrating scenarios like this by picking up a reliable charger. But how do you know which charger is right for your boat? Today we'll be tackling some common questions surrounding marine battery chargers to help you find the right one for your needs.
No, the main thing you'll want to look for is that the charger matches the voltage and chemistry of your boat battery. Any charger that does this will work fine. One of the main advantages of chargers designed specifically for boats is that they tend to be water resistant. This can be a very handy feature, allowing you to mount them permanently to a battery housing on your boat so that you can charge your batteries at any time.
Marine batteries are available in four different chemical types: flooded, gel, AGM (Absorbed Glass Mat) and lithium. When selecting a charger, be sure that it’s compatible with your battery's specific chemistry. Otherwise, it has the potential to damage your battery and shorten its life cycle.
Keep in mind that different types of batteries are used for different purposes on a boat. Starting batteries are responsible for starting your engine, while deep cycle batteries are used to power things like trolling motors, lights and depth finders. It's quite common for boat owners to use batteries with different chemistries to power different things. For instance, let's say you have a flooded battery to start your engine and an AGM battery to power everything else. In that case, you'll want to be sure to have a different charger for each of these batteries, or find a single charger that's compatible with both flooded and AGM chemistries.
For marine batteries, 12V batteries are usually standard, although both 24V and 36V batteries are sometimes used as well. This is true for both starting and deep cycle batteries. It's very important to use a charger compatible with your battery's voltage. Using the wrong charger can harm your battery, forcing you to replace it prematurely. If you're unsure of your boat's voltage requirement, consult your owner's manual.
In order to determine how long it will take to charge your battery, you'll need to know two things, the amp hour rating of your battery and the amperage of the charger you're using. An amp hour (Ah) measures how much amperage a battery can provide per hour. This information is usually available on the manufacturer's website. Likewise, the charger's amperage will be provided in the owner's manual or even on the outside of the charger itself.
Once you have this information you can determine the charging time by diving the amp hour rating by the amperage of your charger. For example, a 75Ah battery using a 7.5 amp charger will take roughly 10 hours to fully charge.
Yes, overcharging your battery can harm your battery, so you want to be sure that you monitor the charging process to prevent that from happening or pick up a charger that shuts off automatically.
Undercharging is also bad for your battery, so you'll want to be sure you charge it on a regular basis. If you're using your battery on a daily basis, a good rule is to keep the batteries on a charger overnight to have them charged up and ready for the next day.
The X2Power 4.0 Amp Automatic Marine Battery Charger is a great choice for your boat. This 4-amp charger is compatible with flooded and AGM batteries of 12-volts. It also protects against overcharging, overheating, sparks and reverse polarity. Plus, it's water resistant up to 4.9 ft. and small enough to be permanently mounted to a battery housing on or inside your boat.
The X2Power 8.0 Amp Marine Battery Charger offers the same benefits of the model above, but with the added ability to charge two batteries at one time.
A reliable charger will help you avoid the disappointment of having a dead battery so you can make the most of your time on the water. Find your marine charger online or stop into your nearest location. Want to learn more about boats? Learn how to pick the best battery for your boat and browse our list of top boating accessories.