The very first thing you should know about RV battery systems is this: it is a critical piece of your RV’s setup. The battery system powers all of the electrical components in your coach.
You’re probably wondering: how do RV battery systems work? The battery system works when you connect the terminals to the connection to power the appliances and other components in the RV. In order to understand that, there are a few other things you’ll need to understand as well.
First of all, it’s critical that you understand, your RV has two battery systems:
- 120-volt AC
- 12-volt DC
Additionally, if you have a motorhome, you’ll also have a car battery system that starts the engine, just like a regular vehicle.
Battery Systems Explained
The 120-volt system runs the major appliances in your RV, such as the fridge or your air conditioner. In order for this system to run, you’ll need to be connected to a power source at a campground or an electric generator that is capable of charging a battery that size. You must keep in mind that solar power doesn’t have the capacity to charge your RV battery.
The 12-volt battery charges when you’re hooked up to power, running a generator, or driving. This battery runs your water system, interior lights, and overhead fans. You can use it while the RV is not hooked up, at least until the battery dies.
Now that we’ve explained the basics of the RV battery system, we can look at some of the commonly asked questions about this critical system.
How To Find The Best RV Battery
When it comes to battery choices for RVs, there are so many different options. When you start asking around, you’ll hear lots of arguments both for and against each one, depending on who you talk to.

- Deep-cycle battery: this is a lead-acid battery, similar to what you’d find on a golf cart or boat. It is a lot like a car battery, but produces steady current over a longer period of time. There are several types of deep-cycle batteries, including:
- Flooded wet-cell
- Absorbed glass mat
- Gel-type
- Lithium battery: alternative to lead-acid batteries and are often used by those who have rigged their RV up for solar power. They are much more expensive, but have more benefits over the other types. Plus, they are typically rated for 5,000 cycles instead of around 400 like the lead-acid batteries.
RV Battery Bank Explained
Contrary to what you might think, an RV battery bank is not a financial institution for batteries but is what happens when you join multiple batteries together. This gives you a boost in voltage or amps when you need it. Following is a list of the types of RV battery banks there are:
- RV Batteries in series
- (2) 6-volt Batteries in series
- RV batteries in parallel
Maintenance Of RV Batteries
One thing to keep in mind is that the maintenance of RV batteries is dependent on the type of battery you are using. For example, if you have lithium batteries, they require basically no upkeep.
On the other hand, there is maintenance required for some of the other types of batteries- and they have different lifespans as well. The best thing to do for maintenance instructions is to check with the manufacturer of the battery. Following are a few of the basics of RV battery maintenance:
- Maintain electrolyte levels
- Keep terminals clean
- Recharge in a timely manner
- Recharge often
Storage Of RV Batteries
Often, RVs are stored for the winter, and batteries will naturally lose their charge over time. This has a negative impact on the lifespan of the battery. Also, freezing can kill a flooded-cell battery.
In order to avoid your battery losing charge and becoming damaged, you might want to remove it and take it home with you. If you can’t do this, there are a few things that you can do to keep your batteries safe.
- Disconnect coach batteries
- Charge batteries as they discharge
- Unplug converters
- Keep a check on batteries periodically
Invest In A Battery Monitor
It’s difficult to determine the actual state of your RV battery without having a battery monitor on them. The monitor will tell you how much energy is flowing into and out of your battery.
There are several different battery monitors on the market and include an LCD display that gives the information you want to know.
Charging Your RV Battery
When connected to an electrical outlet, the battery is charging. Your battery also charges when your RV or generator is running. While it’s true that you can leave your RV plugged in, it can cause the water levels in your wet-cell batteries to dry out quickly. Therefore, if you’re camping long-term, you’ll want to check your batteries often.

Cost Of RV Batteries
As we have already mentioned, the cost of RV batteries varies based on the type of battery you get. On the low end of the spectrum, you have the 12-volt wet-cell lead-acid batteries at a few hundred dollars. On the higher end of the spectrum, you have lithium batteries that cost a few thousand. Of course, the lifespan of lithium batteries makes them worth the investment.
Installation Of RV Batteries
When you are installing an RV battery, you’ll want to make sure everything that draws power is turned off. Note where the current battery is and start by disconnecting the negative cable first and then the positive. If necessary, clean the cables and reattach them to the new battery. Then, test it.
As you can see, RV battery systems are quite complicated- but are a critical component of the RV because it is what makes everything work. The battery system makes your RV home away from home.