It’s one of the oldest sayings in the book. If one is good, then two must be even better, right? That’s a pretty broad statement that can apply to a lot of things, but it DEFINITELY fits the bill when we start talking about deep cycle camping batteries! When it comes to setting up a 12v camping power system, and in particular with regards to solar panels and AGM batteries, the truth is you can never have too much. In fact my recommendation is, incorporate as much of both as your physical storage space and your budget allows!

Look at it like this. The bigger the deep cycle battery in your setup, the more time you have in between needing to recharge. And with solar panels, the more watts of panel you’ve got, the more you can make hay while the sun shines!

An extremely common upgrade for many campers to is to add a second 4WD deep cycle battery to their setup. It’s a fantastic way to take your camping game to a whole new level by extending the time you’re able to spend out bush, but there are a few very important points you must know before you splash your hard-earned cash on a second camping battery. Get these points wrong, and not only will you throw your money away, but you may even damage other components within your system. So, how do you get the most from running twin deep cycle batteries in your camping power setup?

First and foremost – let’s talk the two ways you can join two AGM deep cycle batteries together. The first is called ‘parallel’, and is done by connecting both red (positive) terminals together, and both black (negative) terminals together. When this happens, any other component in your camping power system sees the two batteries as one double-sized camping battery, just with double the amp-hour rating. If you join two 100Ah 12v deep cycle batteries in parallel, you essential end up with a 200Ah 12v deep-cycle battery – giving you double the amount of power reserve to let you run 12v gear like a camping fridge for twice as long.

On the other hand, if you join those two 100Ah 12v deep cycle batteries in series, what you’ll end up with is a system that sees a 100Ah 24v battery – doubling the voltage (meaning most of your camping gear won’t run off it anyway, and may even be damaged in the process) but at the same amp-hour capacity – exactly what you don’t want!

So now we know that we need to connect the two camping aux batteries in parallel, what else is there to consider? It’s very important that the two batteries be identical in size and type. If one deep cycle battery is bigger than the other, it will likely cause long-term issues with the smaller battery discharging faster, and the larger battery not properly charging. As well, owing to the fact that different deep cycle battery types (such as AGM, calcium and lithium) need different rates of charge and charging profiles for maximum service life, there’s every chance you’ll severely reduce the life of one of the batteries by not charging it properly.

So, the simple solution is to choose two camping batteries that are identical in every way – even down to the point of being the exact same brand. That way, assuming you hook them up in parallel like we spoke about a moment ago, the system will simply see one large 4×4 battery that’s able to run your electrical camping gear for ages!

How long? Well, let’s look at another example. The Adventure Kings 138Ah AGM Batteries are absolute monsters on their own, with huge amp hour capacity, but when you add them together and wire them in parallel, you get a whopping 276aH deep cycle battery! However, knowing that the general rule of thumb is you should only ever discharge an AGM battery to 50% of its capacity before recharging it, that means you’ve got approximately 138Ah of capacity to play with. Given that the typical 12v camping fridge draws somewhere around 1amp per hour on average, a pair of 138Ah AGM batteries would then net you almost 6 days of run time before needing recharging!

Just imagine that – you’re pulled up at your all-time favourite campsite and the weather couldn’t be better. You’ve got your dream camping setup all perfectly in place, and you’re not due home for a week. And your camping fridge is running for almost six days off one pair of 138Ah deep cycle camping batteries! That’s the dream right there.

Of course the flipside to it is that when it does come time to charge those batteries back up, you need to put that 138Ah of power back into the battery. Let’s say you’ve got a 25A Kings DC Charger – it’s going to need a solid 6 hours plus of driving to be able to properly recharge your AGM batteries. All good if you’ve got a big drive home, but what if you don’t?

That’s when a camping solar panel comes into play. Hook one up at the beginning of your camping trip, and you’ll keep your camping batteries properly charged as long as you’ve got proper sunlight throughout your camping adventure. It really is the ultimate setup – you’re just sitting back relaxing, safe in the knowledge that you’ve got huge amounts of battery power on hand to keep your fridge running even when you’re not driving and it’s not sunny, but you’ve also got heaps of solar panel and DC charger ready to pump power back into your AGM battery or two when you need it. Now that’s camping like a King!