Motorhome battery

In the motorhome, we basically distinguish two types of batteries: the starter battery and supply batteries. In all motor vehicles, the starter battery is responsible for supplying electrical energy for the engine starter. It also fulfills other important functions by ensuring emergency lighting when the vehicle is stationary and supplying energy to various consumers, from the control unit to the clock and radio. When the engine is running, the alternator recharges the starter battery. This is either a standard wet cell battery or an AGM lead accumulator.

Conventional wet batteries contain the electrolyte in liquid form. This brings with it some peculiarities in handling. Older models in open design (with screw caps) must be maintained, which specifically means that you should regularly refill distilled water. If the highly explosive gases cannot condense in the housing, a hose is included to lead them outside. Due to the danger of the gas and the non-spill-proof design, open wet batteries are no longer used in the interior of motor homes. They are still sometimes used in outdoor storage compartments with good ventilation.

Silica binds the sulfuric acid tightly in this type of battery, so that the electrolytes thicken and a gel is formed. This makes the GEL supply batteries absolutely leak-proof. At FraRon, you can get the RV batteries with a voltage of 12 V and in capacities between 60 and 220 Ah. In its properties, the GEL supply battery is similar to the AGM supply battery. It is also only slightly self-discharging and can also be mounted lying on its side. The design makes it maintenance-free. GEL supply batteries for caravans are characterized by a particularly long service life. Unlike AGM batteries, however, they are not designed for high-current applications (powerful inverters), but rather for endurance and reliability. A particular advantage is that GEL batteries can reach a high depth of discharge without suffering direct damage. However, this requires them to be recharged as quickly as possible.

RV batteries made of lithium or LiFeP04 (lithium iron phosphate) use technology comparable to that used for charging smartphones. Significantly smaller and with a greater current storage capacity than AGM and GEL, they can be easily stowed in motorhomes or boats. They are completely maintenance-free and even an unintentional complete discharge cannot harm them. The integrated battery management system (BMS) protects the cells from damage due to overcharging, deep discharge and overtemperature. Lithium batteries have significantly more usable energy available: While an average depth of discharge of 50 percent is applied to GEL and AGM batteries, up to 90 percent of the energy can be used in RV batteries made of lithium. This makes it possible to design the battery system much smaller, which not only offers space advantages but also significant weight benefits. The high-quality supply batteries for motor homes score points with their fast charging capability and up to 3000 charging cycles. In addition, they are suitable for both high-current draw and micro appliances.

Capacity:
The nominal capacity in Ah differs depending on the model of the RV battery. You can find it in the respective product description here in the FraRon online store. In addition, there is another important parameter: information on the reference time from C1 to C20. The background is that the higher the current drawn, the lower the available capacity. C1 therefore means that the total capacity is used within one hour. C20, on the other hand, describes that the battery is completely discharged in 20 hours.

Charging end voltage:
The end of charge voltage must not be exceeded while charging the RV battery, otherwise the grid corrosion would cause the battery to gas. The overcharging can not only damage the energy storage, but also become very dangerous due to the formation of oxyhydrogen gas. Normally, a wet battery can handle exceeding the end-of-charge voltage for a short time. However, AGM and GEL supply batteries are very sensitive to this. For them, the value is 14.2 to 14.6 V, while for wet technology it is usually 14.4 V.

In order to select the appropriate RV battery, you must first determine your individual consumption, and secondly, determine the appropriate battery type. You should ask yourself the following three questions:

If you know your consumption and also whether your motorhome battery will be supplied by shore power most of the time or you will be largely self-sufficient with your own solar system, there is only one decision left: Wet, AGM, GEL or Lithium LiFeP04 battery? We give you the following recommendations:

Wet batteries are outdated because of the maintenance required and the danger posed by gassing. You should therefore not consider converting to wet technology. AGM and GEL supply batteries are the best solution for most normal consumers. GEL batteries are considered to be a bit more durable and reliable, and are therefore suitable for all motorhome fans who mainly spend their time in the caravan on weekends and vacations. AGM supply batteries charge well from solar panels and are designed to work with high currents and powerful inverters.

The lithium supply batteries are the top of the modern RV batteries as the best energy storage currently available on the market. The many positive features come at a price, which is why the purchase is hardly worthwhile for occasional campers. However, anyone who hibernates in their caravan, tours often and for long periods of time and stays far away from the nearest power outlet or needs a lot of electricity, takes full advantage of all the benefits of the lithium battery.