If you’re heading away camping soon and you’re planning on staying at camp more than one night, you’ll need to consider how you are planning to keep your deep-cycle auxiliary battery topped up. A rough rule of thumb is that a 100Ah battery will comfortably run a fridge and all your camp lighting for one night and well into the second afternoon, but by about the 24 hour mark of relying on your battery, it’s going to need recharging in some fashion. There are three different ways you can reliably recharging your deep-cycle 4WD battery or your deep-cycle AGM battery – by going for a drive, by using solar power or by using a generator. Here’s a comparison of each of the three different options, with each option’s strong-points and drawbacks.

GOING FOR A DRIVE

It’s definitely the most basic way to recharge your batteries – rely on your alternator and your dual-battery system. When you see that your deep-cycle battery is running low, you can put more charge into it by taking your 4×4 for a drive for a couple of hours to pump some voltage back in. Some systems, depending on the battery charger used, can do this just by idling the vehicle but it’s not recommended as a method for charging a deep-cycle battery for a couple of reasons. Firstly, many 4WDs won’t produce full charge at idle but instead will need at least 1500rpm to properly charge batteries.

Leading on from that is the fact that it’s noisy and wasteful to simply have your 4WD idling at 1500rpm at camp, because all you’re doing is using your 4WD as a generator essentially when it isn’t designed to be one. Lastly, idling your 4WD for extended periods of time can be detrimental to its long-term health as diesels need to be worked hard to stay in good shape, and if you have a suspect cooling system you may overheat your motor. However if you want to go for a proper drive somewhere then you can use a couple of hours of driving as a way to charge your deep-cycle battery – if you’re prepared to pack away your rooftop tent, 4×4 awning and the rest of camp to extract your vehicle!

SOLAR POWER

This is definitely by far the quietest, cleanest and greenest option of all deep-cycle battery recharging options. Plug a solar panel like any of the Adventure Kings solar panels into your deep-cycle battery, and as long as it’s facing the sun, you’ll put power back into your 4WD auxiliary battery. The best time to recharge your deep-cycle battery with solar power is early in the morning when the sun is shining but the day hasn’t heated up yet. Heat is actually, and ironically, the enemy of solar panel power production as heat causes voltage drop. Keep your panel wiped down and clean of dust, and continue to move it every couple of hours so it faces the sun all day. Aim for at least 100w, if not 160w of solar power to put as much power back into your batteries as possible.

GENERATOR

The most reliable way to recharge your batteries is with an Adventure Kings Generator and a 240V charger like the CTEK range of battery chargers. This is more of an investment than solar however there’s no method of deep-cycle battery recharging that’s more reliable short of camping at a powered caravan park. Run your generator for about three hours of an early afternoon, and assuming you are running at least a 20A battery charger, you’ll be able to fully recharge your deep-cycle battery. Downsides are that many campsites have restrictions on generator usage, and that in close quarters your neighbours may not love it if you’re constantly running your generator.

However, a couple of hours per day is all it takes and if you do it around midday when everyone is out doing things anyway, you’ll rarely have a drama. Carry a couple of 20m extension leads and put your generator just over the hill or behind a cluster of bushes. Also requires you to carry a jerry can of unleaded fuel to keep the generator running for multiple afternoons in a row.