Before you hit the road, it’s best to ensure your RV, truck, and boat batteries are in good working order. Otherwise, you risk waiting for a tow truck to get you jump-started. To power an energy-hungry home away from home, RV batteries must reliably perform several jobs.
They not only have to start the engine, but they also run lights, water pumps, heat, appliances, and more. Given this tall order, installing the right batteries and maintaining them properly is imperative to problem-free RV excursions.
Basic RV Battery Terminology
RV, truck, and boat batteries are typically broken into two main uses: starting batteries and house batteries.
The battery used to start and run the engine is referred to as a starting battery. Starting batteries deliver high bursts of power over short periods of time.
These batteries are rated in Cold Cranking Amps (CCA). CCA is the number of amps the battery can deliver at 0 degrees Fahrenheit for 30 seconds without dropping below 7.2 volts. The power level you need depends on the cranking requirements of your engine.
Starting RV and truck batteries also are rated by Reserve Capacity. Reserve Capacity (RC) is the duration, in minutes, that a battery will deliver 25 amps at 80 degrees Fahrenheit. RC represents how long the battery will operate essential equipment in the event of an alternator or generator failure.
The batteries used to supply power to the RV itself are commonly referred to as house batteries. These deep-cycle batteries provide a steady amount of current over longer periods of time.
Deep-cycle batteries are designed to be deeply discharged and recharged repeatedly and are rated in Amp Hours (AH) and Reserve Capacity (RC).
The AH rating is the number of amperes (amps) that a battery can deliver for a 20-hour period. This test also is referred to as the 20-hour rate. The larger the AH rating, the more power the battery can deliver over time.
What is Depth of Discharge (DoD)?
Depth of discharge is the percentage of a battery’s capacity that has been used relative to its overall capacity. Conversely, a battery’s state of charge is the percentage of remaining battery capacity. The more often a battery is charged and discharged, the shorter its lifespan.
With most battery types, fully discharging its capacity isn’t recommended. This vastly decreases the battery’s life, so follow the battery manufacturer’s recommended maximum discharge rate if you want to optimize your battery’s performance.
Understanding Battery Types
There are three main types of RV, truck, and boat batteries: flooded, lithium, and absorbent glass mat (AGM). The type of battery you can use will depend, in part, on your RV’s electrical system.
Flooded batteries are still considered the standard for RV and boat use. As RVs require, they are designed to run multiple appliances at once. The downside of flooded batteries is that they require the most maintenance, even in the offseason.
The Interstate Marine/RV and Interstate GC2 batteries below are examples of flooded RV batteries.
AGM batteries are considered the next step up from standard flooded RV batteries. Depending on the model, they offer as much as twice the overall power and three times the lifespan of conventional marine batteries.
They also boast a higher DoD (up to 80%) and require less maintenance in the offseason. The Odyssey battery below is an example of an AGM battery.
Lithium batteries are currently the top-tier RV batteries on the market. They offer a long cycle life (up to 2,000 cycles) and a higher DoD (up to 100%) than flooded and AGM batteries. Lithium-ion batteries also require the least offseason maintenance of these three battery types. The Expion360 battery below is an example of a lithium battery.
Lithium batteries do, however, require charge systems designed for their unique chemistry. You may not be able to swap directly from a flooded or AGM battery to a lithium battery without installing a battery management system or verifying your RV’s current charge system can support a lithium battery.
A battery’s life cycle is the number of charge/discharge cycles it can sustain in its useful life. It will vary dramatically depending on how much of the battery’s capacity you normally utilize.
An RV, truck, or boat battery can last anywhere from one year to several years, depending on how it’s used, maintained, discharged, recharged, and stored. Generally, flooded batteries need to be replaced most frequently, and lithium batteries offer the longest lifespan.
If your RV spends most of its time plugged into an electrical source, battery maintenance will be your main concern, as opposed to worrying about getting the highest AH. On the other hand, if you like boondocking and consider RV hookups optional, you’ll want a deep-cycle battery with the highest AH capacity you can fit in your RV.
Of course, there are ways to keep your batteries charged so you can stay out longer. Running your RV generator is the simplest way, but you can also explore adding solar panels to your RV if you’re interested in extended boondocking.
Check Out the Best Selling RV, Truck, and Boat Batteries
Deep-cycle batteries come in a variety of sizes and have varying AH ratings. Some are designated by group size (24, 27, and 31). Depending on your needs and the space available in your RV, there are several battery selection options, including:
- One 12-volt, group 24 deep-cycle battery that provides 70 – 85 AH.
- Two 12-volt, group 24 batteries wired in parallel to provide 140 – 170 AH.
- Two 6-volt golf cart batteries wired in series to provide about 100 AH or four 6-volt batteries can be wired in series/parallel to provide about 200 AH.
To aid your decision, here are some of the best-selling RV, truck, and boat batteries:
Interstate Marine/RV Deep Cycle 12-Volt Battery, Group Size 24M
- 550 Cold Cranking Amps
- 140-Minute Reserve Capacity (RC) at 25 Amps
- 81 Amp Hours
- Technology: Flooded
- Dimensions: 11″L x 6.875″W x 9″H
- Battery Weight: 46.3 pounds
Interstate GC2 Deep Cycle Extreme 6-Volt Golf Cart Battery
- 447-Minute RC at 75 Amps
- 225 Amp Hours
- Technology: Flooded
- Dimensions: 10.3125″L x 7.125″W x 11″H
- Battery Weight: 62 pounds
Odyssey ODP-AGM24M 12-Volt Marine Dual-Purpose Performance Battery
- 725 Cold Cranking Amps
- 155-Minute RC at 25 Amps
- 63 Amp Hours
- Technology: AGM
- Dimensions: 10.9″L x 6.8″W x 8.8″H
- Battery Weight: 51.4 pounds
Expion360 VPR 4Ever Classic Group 27 12.8-volt Lithium Battery
- 1280 Watt-Hours
- 100 Amp Hours
- Technology: Lithium Iron Phosphate (LiFePO4)
- Dimensions: 11.93″L x 6.81″W x 8.59″H
- Battery Weight: 31.1 pounds
Battery Safety Notes
Parallel connections (+) to (+) and (-) to (-) increase the AH rating by the number of batteries used in the circuit, but not the voltage.
Serial connections (+) to (-) and (-) to (+) increase the voltage, but the AH rating is the same as a single battery. When making either a parallel or serial circuit, all batteries must be of the same rating, age, and design type. It is extremely important not to mix battery types (Flooded, Gel, AGM).
Most RV batteries require some maintenance – even those advertised as “maintenance-free”. A few simple steps will keep your batteries clean and free of corrosion:
- Consult your owner’s manual. Different battery types require different maintenance. So the best place to start is to see what your battery manufacturer recommends.
- Keep it charged. Letting your battery discharge past 12 volts leads to sulfation and shortens its life. Use a voltmeter to measure battery voltage and keep it fully charged.
- Clean terminals regularly. You can also coat with a battery terminal spray.
- Check electrolyte levels monthly. Relevant to flooded and non-sealed AGM batteries. Check and fill with distilled water as needed.
- Remove for long-term storage. When winterizing your RV, remove the batteries, recharge them fully and store them in a cool place. If you don’t remove your battery, ensure the battery disconnect switch is changed to the ‘Off’ position to prevent parasitic draws.
RV, truck, and boat batteries are available at Camping World SuperCenters nationwide. Go here for a listing of Camping World stores.
And regardless of your battery choice, consider Good Sam Roadside Assistance plans so a tow truck is a phone call away when you run into issues on the road.
Interested in selling or trading in your RV? Camping World can help with that too!
Do you have any questions about RV, truck, and boat batteries? Leave a comment below!
I have a 23’ travel trailer. I want to install 2 batteries that I can use solar panels to charge when I’m dry camping. What do you recommend?
I am looking for two deep cycle batteries to replace my house batteries in my motor home.
I need the battery to be 12.5″ long by 6.75 wide. Do you have any in stock at the Fife WA store?
Hi Pat! Lithium is where many folks are going these days, but I would start with some of our content on solar for RV camping.
As for the best setup, it will really depend on your trailer. So I’d suggest contacting a Camping World Performance Center to speak with a specialist that can provide personalized suggestions for what’s best for your trailer and your RV lifestyle: https://rv.campingworld.com/rv-performance-improvements
Hope this helps!