Why is charging RV batteries correctly so important? For starters, who wants to be stuck without power when they need it most? Like in hot, sticky weather, close to a beach but far from campgrounds. Second, careful charging extends the life of your battery. Charging RV batteries the right way ensures they’ll last for countless rounds of camping and boondocking!

The instructions below are for 12V deep cycle RV house batteries. (Or an equivalent, such as 6V batteries wired together).

When to Charge Your RV House Batteries

You have to charge most battery types after they’ve been discharged to 50%. If you wait until the battery is discharged past that mark, you may damage it. Waiting until it’s completely discharged can cut a battery’s life short and reduce efficiency. 

The one exception is lithium batteries. You can discharge LiFePO4 RV house batteries completely with no ill effects. But we recommend charging them when they reach about 80% depletion. This can maximize their life span and performance. 

4 Methods for Charging RV Batteries

There are four ways to charge RV house batteries:

• Shore power
• Generator
• Vehicle alternator
• Solar panels

All of the above are safe, effective ways to charge. But some are faster than others. Choose the right method for your needs. You might want to read up on how to charge via all four methods, since each one is useful for different circumstances. 

Shore Power

By “shore”, we mean regular-old grid power. Many campgrounds have power pedestals where you can juice up. They often dispense 30 or 50 amps, which is double or more than what you get at home. That means you can charge your RV battery fast, and also run some appliances while charging. 

Shore Power with Power Cable and Converter

But plugging into shore power isn’t as simple as just plugging a cable in. The electricity will have a voltage of either 240 or 120. That’s not compatible with a 12 volt battery. Also, shore power is alternating current (AC), while batteries use direct current (DC). So you’ll need a power converter. Then you can plug your RV’s power cable into a 120V AC electrical outlet at the campground.

Shore Power with Battery Charger

A second way to charge via shore power is using a battery charger. But this method won’t allow you to use your appliances at the same time. You’ll have to turn them off so they don’t divert current away from your battery. Be sure to use a charger that suits your battery type (lead acid, AGM, gel, lithium). 

Generator 

You can also charge your RV house batteries with a generator. Generators are reliable, but they’re cumbersome and noisy. That can defeat the purpose of getting away from the hustle and bustle of the city. But generators can come through in a pinch, and some RVs already include them. To use it, plug your RV’s power cable. Follow the included instructions and be sure to bring along extra fuel. 

Vehicle Alternator

Some RVs allow you to charge your RV house batteries while the engine of your towing vehicle is running. The alternator makes this possible by converting mechanical energy into storable battery energy. Sounds convenient? It is if you’ll be spending a lot of time on the road. But it’s by far the slowest method for charging RV batteries. So make sure you have another plan for charging your batteries while parked. 

Solar Panels

Looking for the cleanest, greenest method for charging RV batteries? Set your eyes on the sun (but not literally!) You can harness the sun’s power and convert it to storable battery power with a solar setup. You’ll need solar panels, a charge controller, and a DC/AC Inverter for your AC appliances. 

Solar charging allows you to stray far from campgrounds. It can keep your energy costs at a minimum, as well as your carbon footprint. The one disadvantage? You’re at Mother Nature’s mercy. If your power draw is larger than your reserve, you might find yourself without power on cloudy days.