By Mark Polk
The life of RV batteries varies. Factors include how they’re used, maintained, discharged and recharged, and how they’re stored. A battery cycle is one complete discharge from 100 percent down to about 50 percent and then recharged back to 100 percent.
One important factor to battery life is how deep the battery is cycled each time. If the battery is discharged to 50 percent every day it will last twice as long as if it’s cycled to 80 percent. Keep this in mind when you consider a battery’s amp-hour rating. The amp-hour rating is really cut in half because you don’t want to completely discharge the battery before recharging it. The life expectancy depends on how soon a discharged battery is recharged. The sooner the better.
How this affects you depends on how you use your RV. If you’re plugged into an electrical source most of the time then your main concern is to properly maintain your deep cycle batteries. But if you are dry camping you’ll want the most amp hours.
DEEP CYCLE BATTERIES come in different sizes. Some are designated by group size, like Group 24, 27 and 31. Basically the larger the battery the more amp hours. There are several options. You can use one 12-volt Group 24 deep cycle battery that provides 70 to 85 amp hours or you can use two or more 12-volt batteries wired in parallel. Parallel wiring increases amp hours but not voltage.
If you have the storage space you can switch from standard 12-volt batteries to two of the larger 6-volt golf cart batteries. These pairs of 6-volt batteries need to be wired in series to produce the required 12-volts. Series wiring increases voltage but not amp hours. If this still doesn’t satisfy your requirements you can build larger battery banks using four 6-volt batteries wired in series/parallel that will give you 12-volts and double your AH capacity.