The Ultimate Guide to RV Batteries - Stone Oak Ranch RV Resort

The Ultimate Guide to RV Batteries

Keep your home on wheels running without a hitch. RV batteries are literally the beating heart of your rig, so it’s good to know the ins and outs of how the battery to your RV works. With several types of batteries on the market, we’ll break down for you which will work for you.


Types of RV Batteries

Essentially there are two types of RV batteries: the 12-volt and the chassis battery. If you use home appliances in your RV, you will likely have both of these types of batteries to perform both the running of your rig and your appliances.


The Chassis Battery

Also known as the “starter” battery, this one is found under the hood of your RV next to the engine. It is responsible for starting the auto component using large currents in short bursts. This type of battery includes:


  • Several thin plates to maximize the area exposed to the electrolyte.
  • It is rated in Cold Cranking Amps (CCA).
  • It does not perform deep cycle applications.


The 12-Volt Battery

Also called the “house” battery, this one is responsible for powering the systems inside the body of your RV. Depending on your RV’s size, you might have more than one. The 12-volt is a type of deep cycle battery that powers your motorhome’s appliances and TV. It has the following properties:


  • Designed for deep cycles, the 12-volt has thick plates that are regularly discharged and recharged.
  • It is rated in Reserve Capacity (RC) or Amp Hours (AH).
  • It gives a steady current over longer periods.


If your RV is the towable kind, you will only need the 12-volt battery. Always ensure your 12-volt is working properly, as this also powers the smoke and carbon monoxide detectors.


The Amp Hour Rating Explained

This rating determines how much longer your battery has to run before it needs to be recharged. Technically, it measures the number of amps your battery can deliver in a certain number of hours before the battery is discharged. For instance, if a battery produces 5 amps for 20 hours before discharge, the AH rating would be 100 amp hours. That’s actually a pretty strong battery.


Knowing the proper AH rating for your RV is important for deep cycle batteries, as you want to have the correct amount of voltage that is safe to use for your RV.


Know the Types of Deep Cycle Batteries

Deep cycle batteries come in different sizes. A few are designated by group size, such as groups 24, 27, and 31. The larger the battery, the more amp hours you get. This is important and depends on your needs and the amount of space available, but you have several options:


  • A 12-volt 24 group deep cycle battery enjoys about 70 to 85 AH from one battery.
  • Two 12-volt 24 group batteries, wired together, provide around 140 to 170 AH. Amp hours increase with parallel wiring, but the voltage remains the same.
  • Two large 6-volt golf cart batteries wired together can produce 12 volts needed for an RV. This increases their voltage while leaving the AH unchanged.
  • Four large 6-volt batteries, wired together in a series, is a complex process but does produce the required 12 volts while also doubling your AH capacity.


Factors that Cause RV Battery Failure

  • Undercharging – frequent discharging of batteries without fully recharging them between cycles is a common cause of RV battery failure. If the battery is left discharged for long periods, it is at risk, and many types of batteries are not able to withstand lots of discharge; the sulfate in the battery will harden, causing it to not work properly when they are recharged.
  • Overcharging – when the RV battery is left to charge for too long or is at too high of power, several issues can result. The battery can lose water when overcharged, and enough water loss results in loss of operation. The plates can also become too corroded during overcharging and render your battery unreliable.


How to Maintain the Life of Your RV Batteries

 With proper care, your RV’s battery will have a good life. An important factor in the battery life is how deeply it cycles during each use. A cycle is one complete discharge from 100 percent down to about 50 percent, where it then should be recharged back up to 100 percent.


  • Recharge the battery after use to prevent damage.
  • Use the built-in battery charger when your RV is plugged in.
  • Avoid forcing the battery to power more amperage than is allowed to supply in one hour.
  • If you own deep cycle lead-acid batteries, make sure you get routine inspections and maintenance.
  • If you have lithium-ion batteries, make sure you use the appropriate charger.


The Life Expectancy of an RV Battery

How long your RV battery will last depend on the following factors:


  • The kind of batteries you have.
  • Your usage habits and how much you use your RV.
  • How well you maintain your batteries.
  • How you discharge and recharge them.
  • How you store your RV when not in use.


The Hill Country's Newest RV Resort

Stone Oak Ranch RV Resort

25101 Ronald W Reagan Blvd Georgetown, TX 78633
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