If you’ve ever opened your fridge to find warm beers or woken up to a flat starter battery in the bush, you’ll know just how crucial a good dual battery system is. A reliable dual battery setup for 4WD and caravan adventures is essential for powering your gear, keeping food cold, and ensuring you can get back on the road.
At All12volt, we’ve spent decades designing off-grid power systems built tough for Aussie conditions. Whether you’re a weekend warrior or a long-haul tourer, this guide breaks down everything you need to know about setting up a dual battery system that works.
A dual battery system allows you to run your camping gear from a second (auxiliary) battery while keeping your vehicle’s starting battery isolated and protected. That means you can power fridges, lights, and devices without risking your ability to start the engine in the morning.
It’s the foundation of any serious off-road or touring setup.
Peace of mind: Never drain your starter battery again
More power: Run fridges, lights, fans, pumps, and more
Flexibility: Add solar charging, inverters, and expand your system
Self-sufficiency: Perfect for remote and off-grid camping
Whether you’re travelling with the family or solo exploring the outback, a solid power system keeps the comforts of home close by.
This is the workhorse of your system. Most setups use deep-cycle lithium or AGM batteries for reliable power delivery. Lithium batteries are more efficient, lighter, and charge faster—ideal for frequent travellers. AGM is a more affordable option, but heavier and with shorter life.
Choose a battery size based on your energy needs. A 100Ah lithium battery is a popular choice for running fridges and lights for a few days.
The charger is the brain of your system. It manages how power flows from your alternator to your second battery and ensures your battery gets a proper, safe charge. Modern DC-DC chargers like Victron, Redarc, or Projecta are essential—especially if your vehicle has a smart alternator.
Some also include solar input, so you can add solar panels and charge even while stationary.
A battery monitor like the Victron SmartShunt shows real-time voltage, current draw, and battery state-of-charge. You can view everything from your smartphone, helping you track performance and avoid surprises.
Quality cable, correct fuse sizing, and neat installation are non-negotiable. A poorly wired system is not just inefficient—it’s dangerous. Our custom wiring kits are built for easy install and long-term reliability.
In-vehicle setup: Ideal for 4WDs using under-bonnet or behind-seat battery locations
Canopy setup: Perfect for tradies and tourers running gear from the rear of a ute or tray
Caravan and camper trailer setups: Use the tow vehicle’s alternator to charge house batteries in your caravan via Anderson plugs and DC-DC chargers
Each setup requires slightly different gear, so it’s important to plan based on where and how you camp.
Solar panels: Fixed or portable options to top up your batteries
Inverters: Run 240V appliances like kettles, laptops, or blenders
Anderson plugs: Heavy-duty connectors for trailers, panels, and accessories
Battery boxes: Great for portable or temporary installs
If you love DIY, we’ve got you covered with pre-wired kits, detailed product specs, and expert advice. Not confident with 12V? We offer installation support and custom systems to match your specific rig and goals.
Don’t risk a dodgy setup—power failures out bush aren’t just annoying, they can ruin your trip.
A well-designed dual battery setup for 4WD and caravan gives you freedom, safety, and comfort wherever you camp. Whether you’re building from scratch or upgrading your current system, All12volt is your go-to for reliable gear and trusted advice.
Contact us today and let’s design the perfect system for your setup.
CTA: Shop dual battery kits, DC-DC chargers, batteries, and more—all tested for real Aussie travel.
Contact us: https://www.all12volt.com.au/contact-us/
Need help or have questions?
Email: sales@all12volt.com.au
Phone: 02 4656 4643
Facebook: facebook.com/all12volt
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Who does not love the outdoors and camping? It's a great adventure and opens up new destinations and often unexplored places. But you need to be well equipped with the safe and durable caravan and camping accessories for these outdoor activities. It is undoubtedly thrilling and exciting, but unless you take good care of what you need to do and what you should avoid, there's always a chance of an unpleasant experience. It pays to take sound advice from a 4WD specialist when going on a camping trip.