A dual battery kit lets you run a fridge, lights, inverter and USB from a second (auxiliary) battery, without ever flattening the battery that starts your vehicle. If you camp, tour, work off-grid or live in a van, it is one of the best upgrades you can make. This guide walks through how the kits charge, how much battery you need, and which system suits your setup. When you are ready, browse our full range of dual battery kits.
How a dual battery kit charges
Every kit combines up to three charging sources:
- DC-DC (alternator) charging tops the second battery while you drive. A 25A charger suits a weekend fridge; a 50A charger like the REDARC BCDC Alpha50 recharges bigger lithium banks faster.
- Solar (MPPT) keeps you charged while parked. Most modern kits have a solar regulator built in.
- 240V mains charging tops up at home or on a powered site — handy for caravans and vans.
For the individual components, see our DC-DC chargers and custom dual battery systems.
How much lithium do you need?
As a rough guide: a fridge and lights for a weekend suits 100–120Ah; longer trips or an inverter want 150–210Ah; full-time off-grid living calls for 300Ah or more. Every kit on our site can be bought as a charging kit (system only) or complete with a matched ATG lithium battery — just pick your battery size at checkout.
Choose by how you travel
4WD, ute canopy or tray
Keep it tidy and simple with the Hardkorr Canopy Power System (Control Hub + inverter) or the portable Hardkorr Battery Box build. For an Australian-made pre-wired panel, the REDARC RedWorks Scout25 is a great starting point.
Wagon or day-tourer
The Victron Vehicle Dual Battery System pairs a 50A Orion XS DC-DC charger with SmartSolar for fully Bluetooth-monitored power.
Caravan or camper
Step up to the Victron Caravan Power System with a MultiPlus-II inverter/charger, or Enerdrive's pre-wired Traveller and Explorer canopy systems.
Full off-grid living
For maximum capacity choose the Victron Off-Grid Power System (1kW solar, up to 628Ah), the flagship Enerdrive Adventurer, or the REDARC RedWorks Pioneer50 with RedVision control. The RedWorks Nomad50 sits neatly in between.
The brands we build with
- REDARC — Australian-made, bulletproof DC-DC charging and pre-wired RedWorks panels.
- Enerdrive — the canopy system experts, with complete pre-wired Explorer, Traveller and Adventurer systems.
- Victron Energy — premium charging and inverters with full Bluetooth monitoring, built to order.
- Hardkorr — simple, plug-and-play canopy hubs and portable battery boxes.
Charging kit or complete kit?
Already have a battery? Choose the charging kit. Starting fresh? Pick complete with an ATG lithium battery and we supply the matched battery with your system. Either way, we can supply or professionally fit your kit here in Townsville.
Get the right kit for your setup
Not sure which to choose? Request a quote with your vehicle and daily power use, or browse the full Dual Battery Kits range and pick your battery size at checkout.