In a mobile power system, the performance relies heavily on the quality of the batteries used to store electricity. RV solar commonly utilizes deep cycle valve-controlled lead-acid (VRLA) batteries, with absorbent glass pads (AGMs) being the preferred type.
AGM batteries offer numerous advantages for RV owners. They are sealed, preventing leaks and gas emissions, and require no maintenance. These batteries charge quickly and perform well even in cold temperatures. AGMs are known for their high quality and can operate efficiently across a wide range of temperatures. They are ideal for high-powered devices and have a low self-discharge rate. However, it’s important to note that AGM batteries are sensitive to overcharging and should be used with a charge controller as a precautionary measure.
Gel batteries, another type of sealed battery, charge at a slower rate compared to AGMs. They require a specific charging controller compatible with gel batteries. Gel batteries get their name from the silica (or sand) used to turn the acid inside the cell into a gel-like substance. While this gel prevents spills like AGM batteries, it is more fragile and can be easily damaged under high currents. Fast charging, high discharge, or extreme conditions may lead to serious damage and failure, even with minimal usage.
An alternative option not previously mentioned is lithium batteries. These batteries offer exceptional performance, efficient charging, and a lightweight design. They are safe, maintenance-free, and have a long life cycle. However, it’s worth noting that lithium batteries come with a higher price tag.
Determining the number of batteries you need depends on your RV’s energy consumption. The more appliances you plan to use, the higher the consumption will be. Additionally, RV batteries can be connected together to form a battery pack, providing increased voltage (in series) or capacity (in parallel).
When choosing between 6v and 12v batteries, consider the advantages of each. A 6v battery can offer more ampere-hours, while a 12v battery provides redundancy in certain configurations.
In most RV applications, a 12v current is required, which means using two 6v batteries connected in series to achieve the 12-volt output. If one of the 6v batteries fails, you’ll be left without power. On the other hand, if you connect two 12v batteries and one malfunction, you will still have access to 12v power.
Generally, if you require maximum power or plan to have a large battery pack, opting for 6v batteries is recommended.
When making a purchase, prioritize high-quality AGM batteries for off-grid applications, as they offer a balanced combination of performance and price. Lead-acid batteries have lower upfront costs but require maintenance and have shorter lifespans. While lithium batteries are more expensive initially, they are efficient, maintenance-free, and have longer lifespans.
Always check the battery warranty provided by the manufacturer and inquire about their service and support capabilities.
Part 1 – How Solar Works in Your RV
Part 5 – Power Inverters
Part 6 – Power Converters/Transfer Switches/Battery Chargers
