Caring for Your Camper's Amps

Scott Heiman — 19 June 2019
We uncover a few ways to keep your beastly batteries alive for longer.

We who tow camper trailers often think of ourselves as abandoning luxuries the moment we hit the road. But the truth is, there are, more often than not, plenty of creature comforts along for the ride. Consider the fridge (or two) to keep the food cool, lighting to see at night, and water pressure when we turn on a tap. For the more indulgent among us, there might even be pie warmers, coffee machines, and laptops; plus cameras and phones to charge. All of these things SUCK… electricity, that is.

Having spent over 25 years sleeping under canvas with the military, I really appreciate the benefits these goodies can bring. But I’m less keen on the associated dependence on switches, wiring and batteries. So I wasn’t happy to find myself having to replace our camper’s two batteries, for $400 apiece, after only having them fitted 12 months ago. On this occasion the problem was caused by a switch that had gone faulty before winter, then – left unattended for eight weeks – drained the batteries to the point of no return. 

As I forked out the dosh to set up the camper for its next outing, I reckoned it was time to spend some time in the company of a battery specialist, getting the good oil on how I might extract the most out of the next pair of batteries. So I had a chat with Mark, my local Battery World rep, and I’ve got to say, I’m glad I did. Because I reckon there’s something in what he told us that we’d all benefit from.


One of the main problems that Mark sees is people using the incorrect battery charger for the type of battery. For example, it’s easy to inadvertently use a standard flooded battery charger on an AGM (Absorbed Glass Mat) battery. That can happen because battery chargers simply don’t match the charging parameters of the battery in use. When buying a charger, keep in mind that the recommended charging current for a flooded lead acid battery is 10 per cent of the battery’s C20 ampere hour rating with a charging voltage of 14.4-14.6 volts at 25 degrees Celsius.

Letting a battery discharge below the recommended 50 per cent depth of discharge (DOD) is another common problem Mark sees. Many of us probably know from bitter experience that the deeper a battery is discharged, the worse its service life. Leaving a battery in a discharged state for extended periods of time, with insufficient charging, will cause sulphation and stratification that will reduce the capacity of the battery and reduce its life.  

Other common issues include: mixing different size and age batteries when connecting multiple 12 volt batteries in parallel or series string; and connecting the take-off leads or accessories to only one battery when connected in a parallel string.


In addition to the problems caused by battery discharge, Mark identified a range of other factors that will affect the life of your rig’s batteries. These include:

Temperature. The hotter the environment, the higher the chemical reaction inside the battery, which in turn increases the rate of corrosion. So try to keep batteries away from high heat sources, including under the bonnet or near the exhaust manifold of your tow tug. As for the camper, storing them on the A-frame (drawbar) is not a good idea either. 

Lack of ventilation. Ensure the battery area has good ventilation. For one, this helps keep the heat down. Incidentally, don’t have a flooded acid lead battery inside your living area; store it in its own dedicated storage area.

Lack of maintenance. Batteries need to be regularly checked. Monitor the battery’s State of Charge (SOC) using a voltmeter; regularly check the electrolyte levels in a flooded lead acid battery using a hydrometer; check the terminal connections for cracks or damage (and ensure they’re clean and free of corrosion); check the external condition of the battery housing (sunken walls indicate a failed cell); and, importantly, replace the thing before it fails! You don’t want to end up not being able to run your accessories while you’re out in the bush, surrounded by drop bears and yowies.


While it’s one thing to maintain a battery, it’s another thing to buy the right one in the first place. For example, using a battery that doesn’t have enough capacity to run the accessories in the camper will have you tearing your hair out as you desperately attempt to keep it adequately charged. And despite your best efforts, the battery will probably end up being over-discharged, causing internal damage to the battery plates.

While there’s no one battery type that is best for a camper trailer, there are many factors that need to be considered to ensure we select the right battery for our intended usage. Mark offered some key points to consider:

  • How much are you prepared to spend?
  • Just how much power do all of your accessories need?
  • Do you prefer a maintainable battery or sealed maintenance-free type?
  • Where will it be housed? Will it be near a high-heat source, in a spot with limited access, in the sleeping area or near sensitive electronic equipment?
  • Is weight a consideration? 
  • What recharging capabilities does your camper have? Will you be recharging from an external charger, the tow-tug, solar panels or a generator?

On top of this, when selecting a battery, you shouldn’t get too concerned about whether it’s marked ‘Heavy Duty’ or ‘Marine RV’ or similar. Titles like these are generally marketing statements used to differentiate one product range from another. They won’t tell you what battery is right for you and your rig.

At the end of the day, our conversation with Mark confirmed what we knew. Our camper’s batteries aren’t a ‘set and forget’ accessory. Looking after a battery calls for a similar maintenance approach to the one required by the mechanical components of our rigs. So we need to watch out for the warning signs. Have a battery charging schedule when it’s parked up at home – or simply leave the camper plugged-in when not in use. Check and test the rig’s batteries regularly, and replace them before they fail.

If we follow this approach, and take specialist advice when it’s offered, we can all avoid being left in the dark. 


technical how to battery batteries guide