Selecting an RV battery require an understanding of physical dimension and electrical capacity. Many person assume that any battery will function in any vehicle, but a battery must fit into a specific physical space. Battery sizes is categorized by group sizes, and group sizes are a standardized way to describe the physical footprint of a battery.
You must use a correct group size because the group size determine if a battery will fit into a battery tray. For example, a small Group U1 battery may fit in a small pop-up camper, but a large Group 8D battery is required for a large motorhome. You cannot put a Group 31 battery into a space design for a Group 24 battery, because a Group 31 battery is physically larger than a Group 24 battery.
How to Choose and Care for RV Batteries
The capacity of a battery are measured in amp-hours, and the amp-hours determine how much energy a battery can provides to your appliances. The amount of usable energy in a battery depend on the battery chemistry. If you use flooded lead acid batteries, you can only use about half of the rated amp-hours before the flooded lead acid batteries suffers permanent damage.
Because you can only use half of the capacity of flooded lead acid batteries, you must account for this limit when calculating your power need. Alternatively, you can use Lithium (LiFePO4) batteries, and Lithium (LiFePO4) batteries allow you to use much more of the stored energy than flooded lead acid batteries allow. Lithium (LiFePO4) batteries is also lighter than lead acid batteries, and Lithium (LiFePO4) batteries last long because Lithium (LiFePO4) batteries can complete more charge cycles.
Wiring the batteries correctly is necessary because incorrect wiring can cause damage to your electrical system. You can connect batteries in series to increase the voltage of the battery bank, and you can connect batteries in parallel to increase the amp-hour capacity of the battery bank without changing the voltage. You must determine if your system require higher voltage or higher amp-hour capacity before you begin wiring.
If you wire the batteries incorrectly, you may damage a converter, or you may create a short circuit. You must calculate your daily power consumption so that you know how large of a battery bank you need. You should look at the power draw of every appliance, such as a 12V compressor fridge or a water pump.
Many people underestimates the power draw of small items, such as a fan or a smartphone charger, and this underestimation lead to running out of power. Once you have calculated the total power draw for a twenty-four hour period, you can determine if your battery bank is large enough. A person who use an RV for only a weekend may only need a Group 27 battery, but a person who stays in an RV for a week without shore power will need a larger battery bank.
Maintaining the energy in your battery bank is necessary for continuous power. You can use shore power at a campground to charge your batteries, but you can also use solar panel or an alternator to charge your batteries. If you use Lithium (LiFePO4) batteries, you may need a DC-to-DC charger so that your engine’s alternator can charge the Lithium (LiFePO4) batteries proper.
You must ensure that the energy coming into the battery bank match the energy going out of the battery bank. You must perform maintenance on your batteries to prevent the batteries from failing prematurely. If you use flooded lead acid batteries, you must check the water level and clean the terminals on a monthly basis.
For all type of batteries, you must avoid discharging the battery to zero percent. Draining a battery to zero percent will cause the battery to fail, and draining a battery to zero percent is harmful to both AGM batteries and Lithium (LiFePO4) batteries. If you plan your power consumption and respect the limit of your batteries, you will have more reliable power in your RV.
