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Which battery should I use in my caravan?

by | Jun 24, 2019 | General

Which battery should I use in my caravan?

Which battery should I use in my caravan or 4×4 trailer? Before choosing a replacement battery, there are several factors to consider. Choosing the wrong battery could result in unwanted frustration or lead to additional cost.

Key considerations:

Prior to selecting your replacement battery there are some key factors to consider.

  • How often do you go camping?
  • Where will you be camping?
  • Will you be camping in places where there is no 220V power supply?
  • How long do you plan on camping at a camp site without 220V?
  • Do you have alternative power sources such as Solar Panels?
  • How much are you prepared to spend on batteries?
Battery types:

In recent years great progress has been made in battery technology. The normal Lead-Acid battery as we knew it now comes in various performance packages and batteries such as Lithium Ion offer high energy storage but at a hefty price.

So, which batteries are there to choose from?

  • Engine Start or normal Car Battery
  • Deep Cycle
  • AGM (Absorbed Glass Matt)
  • GEL
  • Lithium Ion
What is the difference between them?

Simply put, both traditional car and the common deep cycle batteries are lead-acid batteries that use the same chemistry for their operation. The difference is in the way that they optimize their design:

A car’s battery is designed to provide a very large amount of current for a short period of time. This surge of current is needed to turn the engine over during starting. Once the engine starts, the alternator provides all the power that the car needs, so a car battery may go through its entire life without ever being drained more than 20 percent of its total capacity. To achieve a large amount of current, a car battery uses thin plates in order to increase its surface area.

Starting or Car Battery: Has many thin plates to achieve low resistance with high surface area thus enabling high current supply for a short period of time. It is not designed for deep cycling.

Starting or Car Battery

A deep cycle battery is designed to provide a steady amount of current over a long period of time. A deep cycle battery can provide a surge when needed, but nothing like the surge a car battery can. It is also designed to be deeply discharged over and over again (something that would ruin a car battery very quickly). To accomplish this, they have thicker plates.

Deep Cycle Battery: Has thicker plates for improved cycling abilities.

Deep Cycle Battery

Source: Battery University

Absorbent Glass Mat (AGM): utilise an Absorbed Glass Matt (AGM) process which is superior to traditional flooded technology. Fine, highly porous, micro-fiber glass separators absorb the electrolyte, increasing efficiency by lowering internal resistance, which in turn boosts capacity. Lower internal resistance also means that the battery can be recharged much faster than conventional flooded or wet lead acid batteries. AGM’s provide much larger capacity in a smaller case size. Typical uses are starter batteries for motorcycles, start-stop function for micro-hybrid cars, as well as caravans and trailers that need some cycling.

GEL VRLA batteries: contain a gelified electrolyte which differs to their AGM counterparts. Sulfuric acid is mixed with silica fume, which makes the resulting mass gel-like and immobile. This creates a completely maintenance free, non-spill lead acid battery product. GEL’s boast greater resistance to extreme temperatures, shock, and vibration. They are capable of withstanding over discharging, which typically causes irreversible damage to Flooded and some AGM batteries. They are ideal in applications where a constant current is required such as golf carts and 4×4 trailers and off-road caravans.

Source: Mr Positive


Having some insight to the different batteries which is the right one for your Conqueror off-road camper? This brings us back to our initial question; how much are you prepared to pay? If money is no object then a good investment would be AGM or GEL’s however, you’ll probably need to upgrade your caravan or trailer’s charging system. One of the drawbacks of these batteries are there specific charging needs.

Car batteries are not the correct batteries to use in your Conqueror, while they are considerably cheaper, they simply cannot cope with deep discharge cycles and you will probably have to replace them a lot sooner resulting in additional expenses.

We recommend using 90 Ah to 105 Ah Deep Cycle batteries which are specifically designed for use in 4×4 caravans and trailers. They will provide adequate power to handle almost all loads in your camper without breaking your piggybank. If you plan on staying off-grid for extended periods rather consider adding a good quality, suitably sized Solar Panel to your power arsenal.

Additional Sources:
Electronics Notes