Maintain Your RV Batteries for a Smoother Off-Grid Trip

The suitcase is packed, the route planned, and the gas tank full. You may think you’re ready for your next RV adventure, but if you haven’t properly maintained your RV batteries, the adventure could stall.

Recreational Vehicles have two main types of batteries - starter and house.

A starter battery (sometimes called a chassis battery) is used to start an RV’s engine.

The high-power density of a starter battery means it’s able to release large amounts of power quickly. It’s perfect for the high current required by a vehicle’s starter motor. Similar starter batteries can be found in nearly all other vehicles, including cars, trucks, and motorcycles.

What makes an RV unique is its house batteries (also known as deep-cycle or coach batteries). House batteries provide a steady amount of current over a long period of time.

In an RV, house batteries power everything from kitchen appliances and lights to smoke detectors.

“Amp hours” (AH) - or Reserve Capacity (RC) -  are used to rate house batteries.

Amp-hours indicate how many amps can be delivered over a period of time before the battery is discharged.

For example, a house battery providing 5 amps for 20 hours = 100 Amp Hours. The same 100 Amp Hour battery also would provide 20 amps for 5 hours.

To increase the amount of Amp Hours available, some RVs use battery banks, in which two or more batteries are joined together.

RV batteries utilize 12-volt direct current (DC) for deep cycling. Deep cycling means the battery is designed to be regularly deeply discharged and use most of its capacity.

During an RV adventure, when not relying on your battery power, you’ll most likely be hooked to “shore power.”

Hooking to shore power means your RV is plugged into a 120-volt power source through the vehicle’s power cord. To utilize shore power, the RV must be plugged into an outside power source, either a generator or an outlet.

When the RV is attached to shore power, it gives the house batteries a chance to recharge. To recharge your house batteries using shore power, make sure your RV has a power converter (it comes standard with most newer model RVs).

Be aware, using shore power with a converter to charge deeply depleted house batteries is a process that can take hours.

An alternative is a stand-alone battery charger, like the D250SE charger, which can draw its power from smart alternators and other DC sources, making it the ideal charger for vehicles that don’t have access to the main power supply.

The dual input capability of the CTEK D250SE is it can draw power from solar and wind sources, in parallel to the alternator, which makes it an environmentally-friendly charging option for RV’ers looking to live “off the grid.”

It is a fully automatic, five-step charger that supplies up to 20A of power to charge, condition and maintain any 12-volt lead-acid service battery from 40 to 300 Ah.

The  D250SE, charges and maintains the starter battery - even if the engine is not running - and charges service batteries from your starter battery without the risk of starting problems.

The most common cause of RV battery failure is sulfation, a buildup of lead sulfate crystals. This occurs when a battery is deprived of a full charge. Sulfate materials crystallize on the discharged portions of the battery plates, damaging the battery.

An RV is especially susceptible to battery failure when it sits in storage. Just because an RV is off or in storage doesn’t mean there isn’t wattage being consumed.

Known as a “parasitic load” items like radios and refrigerators can consume tiny milliamps over time, which drains the battery.

The CTEK SMARTPASS 120 offers fast charging, even on short journeys, using 120A current from the alternator. It can start the engine from the service battery when your starter battery is flat.

The SMARTPASS 120 prioritizes critical functions so they’re always powered up and working when you need them. It offers automatic energy management in a single, easy-to-use unit. There’s no need for traditional diodes or VSR relays.

SMARTPASS 120 ensures critical functions like starters, radios, emergency lights, and communication systems always have the power they need and take priority over noncritical functions.

Variations in temperature contribute to battery depletion. The batteries in a stored or winterized RV will naturally discharge over time.

However, properly maintained house batteries can last up to five years. While in storage, an RV’s batteries should be tested and fully charged at least once a month.

Syncing CTEK’s CTX Battery Sense to your smartphone will show you the state of charge in all of your batteries in real-time. 

Battery Sense provides valuable knowledge about your batteries in a simple, user-friendly and transparent way. Knowledge of your batteries’ charge level makes it easy to monitor their health status and thus maximize your battery performance and service life. This knowledge will allow you to avoid costly battery replacements and annoying vehicle breakdowns.

The RV life is about relaxing, traveling and enjoying the open road. Properly maintaining your RV batteries ensures peace of mind for the road ahead.

Try out our Charger Selection Tool to find out what charger is right for your RV and other vehicles.