If you’ve ever woken up to a flat battery in the middle of nowhere – or had to choose between running your fridge or starting your engine – you already know why a dual battery setup is a must-have for serious touring in Western Australia.
Whether you’re heading up the coast, across the Nullarbor or deep into the Kimberley, having reliable power off-grid makes the whole trip smoother, safer, and way more comfortable. Here’s everything you need to know about dual battery systems and how to get yours sorted.
1. Why Go Dual Battery?
Your vehicle’s main battery is designed to start your engine – not power your fridge, camp lights, or air compressor. When you start running 4×4 accessories off your starter battery, you risk draining it and getting stuck.
A dual battery system solves this by giving you a second battery, dedicated to powering all your 12V gear – without touching your starter battery.
Benefits:
- Keep your fridge running for days
- Charge phones, cameras, drones, and more
- Run LED camp lighting without worry
- Peace of mind you won’t get stranded
2. How Does a Dual Battery System Work?
In a nutshell, a dual battery system separates your main battery (used to start your car) from your auxiliary battery (used for accessories). When you’re driving, the alternator charges both. When you stop, a battery management system (BMS) or isolator ensures only your second battery is used to power your gear.
Basic components include:
- Starter battery
- Auxiliary battery
- DC-DC charger or isolator
- Fuses and wiring
- Battery monitor or volt meter
3. Choosing the Right Auxiliary Battery
Not all batteries are created equal. Here are the common types used in 4WD setups:
- AGM (Absorbent Glass Mat): Reliable, mid-range price, good for most WA trips.
- Lithium (LiFePO4): Lightweight, fast-charging, long-lasting – but more expensive. Great for serious off-grid setups.
- Flooded Lead Acid: Cheaper, but not ideal for 4WD due to maintenance and safety.
For most WA travellers, an AGM or lithium battery between 100Ah – 200Ah will cover you for fridge use, lighting and device charging.
4. DC-DC Charger vs Isolator – What’s the Difference?
If you’re just doing short trips and not too worried about efficiency, a basic isolator might do the job. But for WA touring – especially with modern smart alternators – a DC-DC charger is the better choice.
Why? It ensures your auxiliary battery gets the proper voltage, even over long drives or with variable loads.
Tip: We recommend DC-DC chargers with built-in solar input, so you can top up at camp using a portable panel.
5. Mounting & Wiring – Keep It Safe and Tidy
Depending on your setup, your auxiliary battery can be mounted under the bonnet, in the tub, behind the rear seat, or in a drawer system. The most important thing is that it’s:
- Securely mounted
- Properly fused
- Wired using heavy-duty cabling
At Oceans Automotive, we build clean, reliable systems that suit your vehicle, travel plans and budget.
6. Monitoring Your Power Use
A volt meter or battery monitor gives you real-time feedback on your battery levels, so you’re not guessing. Some even connect to your phone via Bluetooth.
It’s a small upgrade that can save your whole trip.
7. What About Solar?
WA has no shortage of sunshine – so why not use it? Portable solar panels or a fixed solar setup can keep your auxiliary battery topped up at camp.
Perfect for extended stays at the beach or remote bush camps.
8. Custom Setups for WA Conditions
Every traveller’s needs are different. Some just want to keep a fridge cold on weekend getaways. Others are building full touring rigs with inverters, coffee machines and camera gear. We can design a dual battery setup that’s right for:
- Weekend warriors
- Full-time travellers
- Tradies who need mobile power
- Off-grid campers
Ready to Power Up?
A dual battery system is one of the best investments you can make for 4WD travel in WA. Whether you’re planning a big lap or just want to keep the beers cold at camp, Oceans Automotive in Butler, Western Australia, can help you build the right setup from the ground up.
Talk to the team today about fitting your dual battery system.