Dual Battery Systems for 4WDs & Caravans, Warwick & Toowoomba
A well-wired dual battery setup means your fridge keeps running, your lights stay on, and you never wake up to a flat starter battery. We fit complete systems: DC-DC charger, battery, Anderson plug, rated fusing. Done once, done right.
Complete Dual Battery Systems, Done Once
Every dual battery install is scoped, quoted and completed by Nathan. Quality components, correct cable sizing, and tidy wiring throughout.
Second Battery Supply & Install
AGM or lithium options depending on your budget and needs. Sized to your accessory load and how long you camp.
DC-DC Charger
The right way to charge a second battery. A DC-DC charger takes power from your alternator and delivers the correct charge profile for AGM or lithium batteries.
Battery Isolator
Keeps your starter and accessory batteries separate when the engine is off so you never get stuck with a flat main battery.
Anderson Plug
Industry-standard 50A Anderson plug fitted to your vehicle so you can connect a trailer, caravan, or solar panels in seconds.
Fusing & Cable Management
Every circuit fused and tested, every cable run neatly secured. No loose wires, no undersized cables, no shortcuts.
Battery Monitor
Optional but recommended. Lets you see your battery state of charge, voltage, and remaining runtime from a display or app.
Why We Use Victron MPPT Controllers
A simple VSR (voltage-sensitive relay) was fine for old AGM batteries, but modern vehicles with smart alternators and lithium battery setups need something smarter. A DC-DC charger takes the output from your alternator, conditions it, and delivers the correct three-stage charge profile your second battery actually needs.
We fit REDARC BCDC series chargers as our standard recommendation for dual battery installs. REDARC is Australian-designed and built, with a reputation for reliability that serious 4WD owners trust. Their units also accept solar input, so your second battery charges from both the alternator and solar panels simultaneously.
3001.2
Every Install is AS/NZS 3001.2 Compliant
We follow all relevant Australian Standards on every install. Every job, every time.
Based in Warwick, We Travel
Based in Warwick, we travel across Southeast Queensland for dual battery system installs. Mobile service available. We come to you.
Dual Battery System FAQ
Honest answers to the questions we get asked before every job.
Every dual battery setup is scoped to your vehicle and your actual power needs — there's no one-size-fits-all. Get in touch and we'll assess exactly what you need and give you a straight quote.
What Our Customers Say
Nathan installed 2 x 12 volts systems, one in our Motorhome and one in the trailer. Not only is the system fantastic and we never have to worry about our power, but he also fixed faults we had with our old system. The batteries have 7 years warranty, the upgrade to our panels keep the batteries topped up which really helps on cloudy and rainy days. We recommend Nathan to everyone, and he is so easy to deal with.
Jenni & Steve K
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10/10 for everything! Nathan drove to woop woop to install our bushman fridge, new battery system & fans. Last week in 42 degrees our fridge was lovely and cold and the fans were a godsend! We will use Coast Custom 12 Volt for anything we need in our offgrid set up!
Glynis C
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Nathan is a wonderful source of knowledge and Ideas. There is no pressure and helped Improve the efficiency of our stock caravans solar charging system. Work and components are 1st class. He is happy to do the smallest job at a sensible price. It's a relief to have a 5 star technician serviceing the Warwick and Toowoomba regions.
John M
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